From a4552ceb8a7666e50b5e6ca3ffaecf0c4fc4994c Mon Sep 17 00:00:00 2001
From: Christian Couder <chriscool@tuxfamily.org>
Date: Sun, 1 Dec 2013 08:49:14 +0100
Subject: environment: normalize use of prefixcmp() by removing " != 0"

To be able to automatically convert prefixcmp() to starts_with()
we need first to make sure that prefixcmp() is always used in
the same way.

So let's remove " != 0" after prefixcmp().

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/environment.c b/environment.c
index 0a15349..cd2b068 100644
--- a/environment.c
+++ b/environment.c
@@ -171,7 +171,7 @@ const char *get_git_namespace(void)
 
 const char *strip_namespace(const char *namespaced_ref)
 {
-	if (prefixcmp(namespaced_ref, get_git_namespace()) != 0)
+	if (prefixcmp(namespaced_ref, get_git_namespace()))
 		return NULL;
 	return namespaced_ref + namespace_len;
 }
-- 
cgit v0.10.2-6-g49f6


From 3fb5aead2971c6181dbf143295c427175b8bf082 Mon Sep 17 00:00:00 2001
From: Christian Couder <chriscool@tuxfamily.org>
Date: Sun, 1 Dec 2013 08:49:15 +0100
Subject: builtin/remote: remove postfixcmp() and use suffixcmp() instead

Commit 8cc5b290 (git merge -X<option>, 25 Nov 2009) introduced
suffixcmp() with nearly the same implementation as postfixcmp()
that already existed since commit 211c8968 (Make git-remote a
builtin, 29 Feb 2008).

The only difference between the two implementations is that,
when the string is smaller than the suffix, one implementation
returns 1 while the other one returns -1.

But, as postfixcmp() is only used to compare for equality, the
distinction does not matter and does not affect the correctness of
this patch.

As postfixcmp() has always been static in builtin/remote.c
and is used nowhere else, it makes more sense to remove it
and use suffixcmp() instead in builtin/remote.c, rather than
to remove suffixcmp().

Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/remote.c b/builtin/remote.c
index 4e14891..9b3a98e 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -80,14 +80,6 @@ static int verbose;
 static int show_all(void);
 static int prune_remote(const char *remote, int dry_run);
 
-static inline int postfixcmp(const char *string, const char *postfix)
-{
-	int len1 = strlen(string), len2 = strlen(postfix);
-	if (len1 < len2)
-		return 1;
-	return strcmp(string + len1 - len2, postfix);
-}
-
 static int fetch_remote(const char *name)
 {
 	const char *argv[] = { "fetch", name, NULL, NULL };
@@ -277,13 +269,13 @@ static int config_read_branches(const char *key, const char *value, void *cb)
 		enum { REMOTE, MERGE, REBASE } type;
 
 		key += 7;
-		if (!postfixcmp(key, ".remote")) {
+		if (!suffixcmp(key, ".remote")) {
 			name = xstrndup(key, strlen(key) - 7);
 			type = REMOTE;
-		} else if (!postfixcmp(key, ".merge")) {
+		} else if (!suffixcmp(key, ".merge")) {
 			name = xstrndup(key, strlen(key) - 6);
 			type = MERGE;
-		} else if (!postfixcmp(key, ".rebase")) {
+		} else if (!suffixcmp(key, ".rebase")) {
 			name = xstrndup(key, strlen(key) - 7);
 			type = REBASE;
 		} else
-- 
cgit v0.10.2-6-g49f6


From 956623157f828b2b4fd91a9bc5e78ba8e42437d9 Mon Sep 17 00:00:00 2001
From: Christian Couder <chriscool@tuxfamily.org>
Date: Sun, 1 Dec 2013 08:49:16 +0100
Subject: strbuf: introduce starts_with() and ends_with()

prefixcmp() and suffixcmp() share the common "cmp" suffix that
typically are used to name functions that can be used for ordering,
but they can't, because they are not antisymmetric:

        prefixcmp("foo", "foobar") < 0
        prefixcmp("foobar", "foo") == 0

We in fact do not use these functions for ordering.  Replace them
with functions that just check for equality.

Add starts_with() and end_with() that will be used to replace
prefixcmp() and suffixcmp(), respectively, as the first step.  These
are named after corresponding functions/methods in programming
languages, like Java, Python and Ruby.

In vcs-svn/fast_export.c, there was already an ends_with() function
that did the same thing. Let's use the new one instead while at it.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/git-compat-util.h b/git-compat-util.h
index 7776f12..b73916b 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -350,7 +350,9 @@ extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_lis
 extern void set_error_routine(void (*routine)(const char *err, va_list params));
 extern void set_die_is_recursing_routine(int (*routine)(void));
 
+extern int starts_with(const char *str, const char *prefix);
 extern int prefixcmp(const char *str, const char *prefix);
+extern int ends_with(const char *str, const char *suffix);
 extern int suffixcmp(const char *str, const char *suffix);
 
 static inline const char *skip_prefix(const char *str, const char *prefix)
diff --git a/strbuf.c b/strbuf.c
index 1170d01..83caf4a 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -1,6 +1,15 @@
 #include "cache.h"
 #include "refs.h"
 
+int starts_with(const char *str, const char *prefix)
+{
+	for (; ; str++, prefix++)
+		if (!*prefix)
+			return 1;
+		else if (*str != *prefix)
+			return 0;
+}
+
 int prefixcmp(const char *str, const char *prefix)
 {
 	for (; ; str++, prefix++)
@@ -10,6 +19,15 @@ int prefixcmp(const char *str, const char *prefix)
 			return (unsigned char)*prefix - (unsigned char)*str;
 }
 
+int ends_with(const char *str, const char *suffix)
+{
+	int len = strlen(str), suflen = strlen(suffix);
+	if (len < suflen)
+		return 0;
+	else
+		return !strcmp(str + len - suflen, suffix);
+}
+
 int suffixcmp(const char *str, const char *suffix)
 {
 	int len = strlen(str), suflen = strlen(suffix);
diff --git a/vcs-svn/fast_export.c b/vcs-svn/fast_export.c
index f2b23c8..bd0f2c2 100644
--- a/vcs-svn/fast_export.c
+++ b/vcs-svn/fast_export.c
@@ -162,22 +162,13 @@ static void die_short_read(struct line_buffer *input)
 	die("invalid dump: unexpected end of file");
 }
 
-static int ends_with(const char *s, size_t len, const char *suffix)
-{
-	const size_t suffixlen = strlen(suffix);
-	if (len < suffixlen)
-		return 0;
-	return !memcmp(s + len - suffixlen, suffix, suffixlen);
-}
-
 static int parse_cat_response_line(const char *header, off_t *len)
 {
-	size_t headerlen = strlen(header);
 	uintmax_t n;
 	const char *type;
 	const char *end;
 
-	if (ends_with(header, headerlen, " missing"))
+	if (ends_with(header, " missing"))
 		return error("cat-blob reports missing blob: %s", header);
 	type = strstr(header, " blob ");
 	if (!type)
-- 
cgit v0.10.2-6-g49f6


From 59556548230e617b837343c2c07e357e688e2ca4 Mon Sep 17 00:00:00 2001
From: Christian Couder <chriscool@tuxfamily.org>
Date: Sat, 30 Nov 2013 21:55:40 +0100
Subject: replace {pre,suf}fixcmp() with {starts,ends}_with()

Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.

The change can be recreated by mechanically applying this:

    $ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
      grep -v strbuf\\.c |
      xargs perl -pi -e '
        s|!prefixcmp\(|starts_with\(|g;
        s|prefixcmp\(|!starts_with\(|g;
        s|!suffixcmp\(|ends_with\(|g;
        s|suffixcmp\(|!ends_with\(|g;
      '

on the result of preparatory changes in this series.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/alias.c b/alias.c
index 9938f03..5efc3d6 100644
--- a/alias.c
+++ b/alias.c
@@ -5,7 +5,7 @@ static char *alias_val;
 
 static int alias_lookup_cb(const char *k, const char *v, void *cb)
 {
-	if (!prefixcmp(k, "alias.") && !strcmp(k + 6, alias_key)) {
+	if (starts_with(k, "alias.") && !strcmp(k + 6, alias_key)) {
 		if (!v)
 			return config_error_nonbool(k);
 		alias_val = xstrdup(v);
diff --git a/attr.c b/attr.c
index 0e774c6..8d13d70 100644
--- a/attr.c
+++ b/attr.c
@@ -211,7 +211,7 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
 	name = cp;
 	namelen = strcspn(name, blank);
 	if (strlen(ATTRIBUTE_MACRO_PREFIX) < namelen &&
-	    !prefixcmp(name, ATTRIBUTE_MACRO_PREFIX)) {
+	    starts_with(name, ATTRIBUTE_MACRO_PREFIX)) {
 		if (!macro_ok) {
 			fprintf(stderr, "%s not allowed: %s:%d\n",
 				name, src, lineno);
diff --git a/bisect.c b/bisect.c
index 1e46a4f..37200b4 100644
--- a/bisect.c
+++ b/bisect.c
@@ -406,9 +406,9 @@ static int register_ref(const char *refname, const unsigned char *sha1,
 	if (!strcmp(refname, "bad")) {
 		current_bad_sha1 = xmalloc(20);
 		hashcpy(current_bad_sha1, sha1);
-	} else if (!prefixcmp(refname, "good-")) {
+	} else if (starts_with(refname, "good-")) {
 		sha1_array_append(&good_revs, sha1);
-	} else if (!prefixcmp(refname, "skip-")) {
+	} else if (starts_with(refname, "skip-")) {
 		sha1_array_append(&skipped_revs, sha1);
 	}
 
diff --git a/branch.c b/branch.c
index 9e6c68e..723a36b 100644
--- a/branch.c
+++ b/branch.c
@@ -50,7 +50,7 @@ static int should_setup_rebase(const char *origin)
 void install_branch_config(int flag, const char *local, const char *origin, const char *remote)
 {
 	const char *shortname = remote + 11;
-	int remote_is_branch = !prefixcmp(remote, "refs/heads/");
+	int remote_is_branch = starts_with(remote, "refs/heads/");
 	struct strbuf key = STRBUF_INIT;
 	int rebasing = should_setup_rebase(origin);
 
@@ -272,7 +272,7 @@ void create_branch(const char *head,
 		break;
 	case 1:
 		/* Unique completion -- good, only if it is a real branch */
-		if (prefixcmp(real_ref, "refs/heads/") &&
+		if (!starts_with(real_ref, "refs/heads/") &&
 		    validate_remote_tracking_branch(real_ref)) {
 			if (explicit_tracking)
 				die(_(upstream_not_branch), start_name);
diff --git a/builtin/apply.c b/builtin/apply.c
index ef32e4f..b0d0986 100644
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -1409,10 +1409,10 @@ static void recount_diff(const char *line, int size, struct fragment *fragment)
 		case '\\':
 			continue;
 		case '@':
-			ret = size < 3 || prefixcmp(line, "@@ ");
+			ret = size < 3 || !starts_with(line, "@@ ");
 			break;
 		case 'd':
-			ret = size < 5 || prefixcmp(line, "diff ");
+			ret = size < 5 || !starts_with(line, "diff ");
 			break;
 		default:
 			ret = -1;
@@ -1798,11 +1798,11 @@ static struct fragment *parse_binary_hunk(char **buf_p,
 
 	*status_p = 0;
 
-	if (!prefixcmp(buffer, "delta ")) {
+	if (starts_with(buffer, "delta ")) {
 		patch_method = BINARY_DELTA_DEFLATED;
 		origlen = strtoul(buffer + 6, NULL, 10);
 	}
-	else if (!prefixcmp(buffer, "literal ")) {
+	else if (starts_with(buffer, "literal ")) {
 		patch_method = BINARY_LITERAL_DEFLATED;
 		origlen = strtoul(buffer + 8, NULL, 10);
 	}
@@ -3627,12 +3627,12 @@ static int preimage_sha1_in_gitlink_patch(struct patch *p, unsigned char sha1[20
 	    hunk->oldpos == 1 && hunk->oldlines == 1 &&
 	    /* does preimage begin with the heading? */
 	    (preimage = memchr(hunk->patch, '\n', hunk->size)) != NULL &&
-	    !prefixcmp(++preimage, heading) &&
+	    starts_with(++preimage, heading) &&
 	    /* does it record full SHA-1? */
 	    !get_sha1_hex(preimage + sizeof(heading) - 1, sha1) &&
 	    preimage[sizeof(heading) + 40 - 1] == '\n' &&
 	    /* does the abbreviated name on the index line agree with it? */
-	    !prefixcmp(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
+	    starts_with(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
 		return 0; /* it all looks fine */
 
 	/* we may have full object name on the index line */
diff --git a/builtin/archive.c b/builtin/archive.c
index 49178f1..a1e3b94 100644
--- a/builtin/archive.c
+++ b/builtin/archive.c
@@ -57,9 +57,9 @@ static int run_remote_archiver(int argc, const char **argv,
 	if (!buf)
 		die(_("git archive: expected ACK/NAK, got EOF"));
 	if (strcmp(buf, "ACK")) {
-		if (!prefixcmp(buf, "NACK "))
+		if (starts_with(buf, "NACK "))
 			die(_("git archive: NACK %s"), buf + 5);
-		if (!prefixcmp(buf, "ERR "))
+		if (starts_with(buf, "ERR "))
 			die(_("remote error: %s"), buf + 4);
 		die(_("git archive: protocol error"));
 	}
diff --git a/builtin/branch.c b/builtin/branch.c
index f157f92..c5953e5 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -81,13 +81,13 @@ static int parse_branch_color_slot(const char *var, int ofs)
 
 static int git_branch_config(const char *var, const char *value, void *cb)
 {
-	if (!prefixcmp(var, "column."))
+	if (starts_with(var, "column."))
 		return git_column_config(var, value, "branch", &colopts);
 	if (!strcmp(var, "color.branch")) {
 		branch_use_color = git_config_colorbool(var, value);
 		return 0;
 	}
-	if (!prefixcmp(var, "color.branch.")) {
+	if (starts_with(var, "color.branch.")) {
 		int slot = parse_branch_color_slot(var, 13);
 		if (slot < 0)
 			return 0;
@@ -868,7 +868,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	if (!strcmp(head, "HEAD")) {
 		detached = 1;
 	} else {
-		if (prefixcmp(head, "refs/heads/"))
+		if (!starts_with(head, "refs/heads/"))
 			die(_("HEAD not found below refs/heads!"));
 		head += 11;
 	}
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 54f80bd..7e939b0 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -781,7 +781,7 @@ static int switch_branches(const struct checkout_opts *opts,
 	if (!(flag & REF_ISSYMREF))
 		old.path = NULL;
 
-	if (old.path && !prefixcmp(old.path, "refs/heads/"))
+	if (old.path && starts_with(old.path, "refs/heads/"))
 		old.name = old.path + strlen("refs/heads/");
 
 	if (!new->name) {
@@ -816,7 +816,7 @@ static int git_checkout_config(const char *var, const char *value, void *cb)
 		return 0;
 	}
 
-	if (!prefixcmp(var, "submodule."))
+	if (starts_with(var, "submodule."))
 		return parse_submodule_config_option(var, value);
 
 	return git_xmerge_config(var, value, NULL);
@@ -1151,9 +1151,9 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 		const char *argv0 = argv[0];
 		if (!argc || !strcmp(argv0, "--"))
 			die (_("--track needs a branch name"));
-		if (!prefixcmp(argv0, "refs/"))
+		if (starts_with(argv0, "refs/"))
 			argv0 += 5;
-		if (!prefixcmp(argv0, "remotes/"))
+		if (starts_with(argv0, "remotes/"))
 			argv0 += 8;
 		argv0 = strchr(argv0, '/');
 		if (!argv0 || !argv0[1])
diff --git a/builtin/clean.c b/builtin/clean.c
index 615cd57..2f26297 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -100,7 +100,7 @@ static int parse_clean_color_slot(const char *var)
 
 static int git_clean_config(const char *var, const char *value, void *cb)
 {
-	if (!prefixcmp(var, "column."))
+	if (starts_with(var, "column."))
 		return git_column_config(var, value, "clean", &colopts);
 
 	/* honors the color.interactive* config variables which also
@@ -109,7 +109,7 @@ static int git_clean_config(const char *var, const char *value, void *cb)
 		clean_use_color = git_config_colorbool(var, value);
 		return 0;
 	}
-	if (!prefixcmp(var, "color.interactive.")) {
+	if (starts_with(var, "color.interactive.")) {
 		int slot = parse_clean_color_slot(var +
 						  strlen("color.interactive."));
 		if (slot < 0)
diff --git a/builtin/clone.c b/builtin/clone.c
index 874e0fd..ec4d1cd 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -508,9 +508,9 @@ static void write_followtags(const struct ref *refs, const char *msg)
 {
 	const struct ref *ref;
 	for (ref = refs; ref; ref = ref->next) {
-		if (prefixcmp(ref->name, "refs/tags/"))
+		if (!starts_with(ref->name, "refs/tags/"))
 			continue;
-		if (!suffixcmp(ref->name, "^{}"))
+		if (ends_with(ref->name, "^{}"))
 			continue;
 		if (!has_sha1_file(ref->old_sha1))
 			continue;
@@ -578,7 +578,7 @@ static void update_remote_refs(const struct ref *refs,
 static void update_head(const struct ref *our, const struct ref *remote,
 			const char *msg)
 {
-	if (our && !prefixcmp(our->name, "refs/heads/")) {
+	if (our && starts_with(our->name, "refs/heads/")) {
 		/* Local default branch link */
 		create_symref("HEAD", our->name, NULL);
 		if (!option_bare) {
@@ -625,7 +625,7 @@ static int checkout(void)
 		if (advice_detached_head)
 			detach_advice(sha1_to_hex(sha1));
 	} else {
-		if (prefixcmp(head, "refs/heads/"))
+		if (!starts_with(head, "refs/heads/"))
 			die(_("HEAD not found below refs/heads!"));
 	}
 	free(head);
diff --git a/builtin/column.c b/builtin/column.c
index e125a55..7581852 100644
--- a/builtin/column.c
+++ b/builtin/column.c
@@ -34,7 +34,7 @@ int cmd_column(int argc, const char **argv, const char *prefix)
 	};
 
 	/* This one is special and must be the first one */
-	if (argc > 1 && !prefixcmp(argv[1], "--command=")) {
+	if (argc > 1 && starts_with(argv[1], "--command=")) {
 		command = argv[1] + 10;
 		git_config(column_config, (void *)command);
 	} else
diff --git a/builtin/commit.c b/builtin/commit.c
index 6ab4605..4f765a2 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -733,7 +733,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 				eol = nl - sb.buf;
 			else
 				eol = sb.len;
-			if (!prefixcmp(sb.buf + previous, "\nConflicts:\n")) {
+			if (starts_with(sb.buf + previous, "\nConflicts:\n")) {
 				ignore_footer = sb.len - previous;
 				break;
 			}
@@ -904,7 +904,7 @@ static int rest_is_empty(struct strbuf *sb, int start)
 			eol = sb->len;
 
 		if (strlen(sign_off_header) <= eol - i &&
-		    !prefixcmp(sb->buf + i, sign_off_header)) {
+		    starts_with(sb->buf + i, sign_off_header)) {
 			i = eol;
 			continue;
 		}
@@ -1183,7 +1183,7 @@ static int git_status_config(const char *k, const char *v, void *cb)
 {
 	struct wt_status *s = cb;
 
-	if (!prefixcmp(k, "column."))
+	if (starts_with(k, "column."))
 		return git_column_config(k, v, "status", &s->colopts);
 	if (!strcmp(k, "status.submodulesummary")) {
 		int is_bool;
@@ -1211,7 +1211,7 @@ static int git_status_config(const char *k, const char *v, void *cb)
 		s->display_comment_prefix = git_config_bool(k, v);
 		return 0;
 	}
-	if (!prefixcmp(k, "status.color.") || !prefixcmp(k, "color.status.")) {
+	if (starts_with(k, "status.color.") || starts_with(k, "color.status.")) {
 		int slot = parse_status_slot(k, 13);
 		if (slot < 0)
 			return 0;
@@ -1377,7 +1377,7 @@ static void print_summary(const char *prefix, const unsigned char *sha1,
 
 	head = resolve_ref_unsafe("HEAD", junk_sha1, 0, NULL);
 	printf("[%s%s ",
-		!prefixcmp(head, "refs/heads/") ?
+		starts_with(head, "refs/heads/") ?
 			head + 11 :
 			!strcmp(head, "HEAD") ?
 				_("detached HEAD") :
diff --git a/builtin/describe.c b/builtin/describe.c
index 6f62109..7db43da 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -141,7 +141,7 @@ static void add_to_known_names(const char *path,
 
 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 {
-	int is_tag = !prefixcmp(path, "refs/tags/");
+	int is_tag = starts_with(path, "refs/tags/");
 	unsigned char peeled[20];
 	int is_annotated, prio;
 
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 78250ea..ea55a24 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -476,7 +476,7 @@ static void handle_tag(const char *name, struct tag *tag)
 		}
 	}
 
-	if (!prefixcmp(name, "refs/tags/"))
+	if (starts_with(name, "refs/tags/"))
 		name += 10;
 	printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
 	       name, tagged_mark,
diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
index c8e8582..10fcdc2 100644
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@ -48,11 +48,11 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 	for (i = 1; i < argc && *argv[i] == '-'; i++) {
 		const char *arg = argv[i];
 
-		if (!prefixcmp(arg, "--upload-pack=")) {
+		if (starts_with(arg, "--upload-pack=")) {
 			args.uploadpack = arg + 14;
 			continue;
 		}
-		if (!prefixcmp(arg, "--exec=")) {
+		if (starts_with(arg, "--exec=")) {
 			args.uploadpack = arg + 7;
 			continue;
 		}
@@ -85,7 +85,7 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 			args.verbose = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--depth=")) {
+		if (starts_with(arg, "--depth=")) {
 			args.depth = strtol(arg + 8, NULL, 0);
 			continue;
 		}
diff --git a/builtin/fetch.c b/builtin/fetch.c
index bd7a101..4dd8250 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -313,7 +313,7 @@ static int update_local_ref(struct ref *ref,
 	}
 
 	if (!is_null_sha1(ref->old_sha1) &&
-	    !prefixcmp(ref->name, "refs/tags/")) {
+	    starts_with(ref->name, "refs/tags/")) {
 		int r;
 		r = s_update_ref("updating tag", ref, 0);
 		strbuf_addf(display, "%c %-*s %-*s -> %s%s",
@@ -336,10 +336,10 @@ static int update_local_ref(struct ref *ref,
 		 * more likely to follow a standard layout.
 		 */
 		const char *name = remote_ref ? remote_ref->name : "";
-		if (!prefixcmp(name, "refs/tags/")) {
+		if (starts_with(name, "refs/tags/")) {
 			msg = "storing tag";
 			what = _("[new tag]");
-		} else if (!prefixcmp(name, "refs/heads/")) {
+		} else if (starts_with(name, "refs/heads/")) {
 			msg = "storing head";
 			what = _("[new branch]");
 		} else {
@@ -471,15 +471,15 @@ static int store_updated_refs(const char *raw_url, const char *remote_name,
 				kind = "";
 				what = "";
 			}
-			else if (!prefixcmp(rm->name, "refs/heads/")) {
+			else if (starts_with(rm->name, "refs/heads/")) {
 				kind = "branch";
 				what = rm->name + 11;
 			}
-			else if (!prefixcmp(rm->name, "refs/tags/")) {
+			else if (starts_with(rm->name, "refs/tags/")) {
 				kind = "tag";
 				what = rm->name + 10;
 			}
-			else if (!prefixcmp(rm->name, "refs/remotes/")) {
+			else if (starts_with(rm->name, "refs/remotes/")) {
 				kind = "remote-tracking branch";
 				what = rm->name + 13;
 			}
@@ -644,7 +644,7 @@ static void find_non_local_tags(struct transport *transport,
 
 	for_each_ref(add_existing, &existing_refs);
 	for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
-		if (prefixcmp(ref->name, "refs/tags/"))
+		if (!starts_with(ref->name, "refs/tags/"))
 			continue;
 
 		/*
@@ -653,7 +653,7 @@ static void find_non_local_tags(struct transport *transport,
 		 * to fetch then we can mark the ref entry in the list
 		 * as one to ignore by setting util to NULL.
 		 */
-		if (!suffixcmp(ref->name, "^{}")) {
+		if (ends_with(ref->name, "^{}")) {
 			if (item && !has_sha1_file(ref->old_sha1) &&
 			    !will_fetch(head, ref->old_sha1) &&
 			    !has_sha1_file(item->util) &&
@@ -892,7 +892,7 @@ static int get_remote_group(const char *key, const char *value, void *priv)
 {
 	struct remote_group_data *g = priv;
 
-	if (!prefixcmp(key, "remotes.") &&
+	if (starts_with(key, "remotes.") &&
 			!strcmp(key + 8, g->name)) {
 		/* split list by white space */
 		int space = strcspn(value, " \t\n");
diff --git a/builtin/fmt-merge-msg.c b/builtin/fmt-merge-msg.c
index 1c04070..3906eda 100644
--- a/builtin/fmt-merge-msg.c
+++ b/builtin/fmt-merge-msg.c
@@ -109,7 +109,7 @@ static int handle_line(char *line, struct merge_parents *merge_parents)
 	if (len < 43 || line[40] != '\t')
 		return 1;
 
-	if (!prefixcmp(line + 41, "not-for-merge"))
+	if (starts_with(line + 41, "not-for-merge"))
 		return 0;
 
 	if (line[41] != '\t')
@@ -155,16 +155,16 @@ static int handle_line(char *line, struct merge_parents *merge_parents)
 	if (pulling_head) {
 		origin = src;
 		src_data->head_status |= 1;
-	} else if (!prefixcmp(line, "branch ")) {
+	} else if (starts_with(line, "branch ")) {
 		origin_data->is_local_branch = 1;
 		origin = line + 7;
 		string_list_append(&src_data->branch, origin);
 		src_data->head_status |= 2;
-	} else if (!prefixcmp(line, "tag ")) {
+	} else if (starts_with(line, "tag ")) {
 		origin = line;
 		string_list_append(&src_data->tag, origin + 4);
 		src_data->head_status |= 2;
-	} else if (!prefixcmp(line, "remote-tracking branch ")) {
+	} else if (starts_with(line, "remote-tracking branch ")) {
 		origin = line + strlen("remote-tracking branch ");
 		string_list_append(&src_data->r_branch, origin);
 		src_data->head_status |= 2;
@@ -605,7 +605,7 @@ int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
 		resolve_refdup("HEAD", head_sha1, 1, NULL);
 	if (!current_branch)
 		die("No current branch");
-	if (!prefixcmp(current_branch, "refs/heads/"))
+	if (starts_with(current_branch, "refs/heads/"))
 		current_branch += 11;
 
 	find_merge_parents(&merge_parents, in, head_sha1);
diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index d096051..883d383 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@@ -441,7 +441,7 @@ static void grab_person(const char *who, struct atom_value *val, int deref, stru
 		if (name[wholen] != 0 &&
 		    strcmp(name + wholen, "name") &&
 		    strcmp(name + wholen, "email") &&
-		    prefixcmp(name + wholen, "date"))
+		    !starts_with(name + wholen, "date"))
 			continue;
 		if (!wholine)
 			wholine = find_wholine(who, wholen, buf, sz);
@@ -453,7 +453,7 @@ static void grab_person(const char *who, struct atom_value *val, int deref, stru
 			v->s = copy_name(wholine);
 		else if (!strcmp(name + wholen, "email"))
 			v->s = copy_email(wholine);
-		else if (!prefixcmp(name + wholen, "date"))
+		else if (starts_with(name + wholen, "date"))
 			grab_date(wholine, v, name);
 	}
 
@@ -475,7 +475,7 @@ static void grab_person(const char *who, struct atom_value *val, int deref, stru
 		if (deref)
 			name++;
 
-		if (!prefixcmp(name, "creatordate"))
+		if (starts_with(name, "creatordate"))
 			grab_date(wholine, v, name);
 		else if (!strcmp(name, "creator"))
 			v->s = copy_line(wholine);
@@ -655,14 +655,14 @@ static void populate_value(struct refinfo *ref)
 			name++;
 		}
 
-		if (!prefixcmp(name, "refname"))
+		if (starts_with(name, "refname"))
 			refname = ref->refname;
-		else if (!prefixcmp(name, "symref"))
+		else if (starts_with(name, "symref"))
 			refname = ref->symref ? ref->symref : "";
-		else if (!prefixcmp(name, "upstream")) {
+		else if (starts_with(name, "upstream")) {
 			struct branch *branch;
 			/* only local branches may have an upstream */
-			if (prefixcmp(ref->refname, "refs/heads/"))
+			if (!starts_with(ref->refname, "refs/heads/"))
 				continue;
 			branch = branch_get(ref->refname + 11);
 
diff --git a/builtin/fsck.c b/builtin/fsck.c
index 97ce678..1affdd5 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -442,7 +442,7 @@ static void fsck_dir(int i, char *path)
 			add_sha1_list(sha1, DIRENT_SORT_HINT(de));
 			continue;
 		}
-		if (!prefixcmp(de->d_name, "tmp_obj_"))
+		if (starts_with(de->d_name, "tmp_obj_"))
 			continue;
 		fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 	}
@@ -484,7 +484,7 @@ static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, in
 
 static int is_branch(const char *refname)
 {
-	return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
+	return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
 }
 
 static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
@@ -566,7 +566,7 @@ static int fsck_head_link(void)
 	if (!strcmp(head_points_at, "HEAD"))
 		/* detached HEAD */
 		null_is_error = 1;
-	else if (prefixcmp(head_points_at, "refs/heads/"))
+	else if (!starts_with(head_points_at, "refs/heads/"))
 		return error("HEAD points to something strange (%s)",
 			     head_points_at);
 	if (is_null_sha1(head_sha1)) {
diff --git a/builtin/help.c b/builtin/help.c
index f1e236b..cc17e67 100644
--- a/builtin/help.c
+++ b/builtin/help.c
@@ -100,7 +100,7 @@ static int check_emacsclient_version(void)
 	 */
 	finish_command(&ec_process);
 
-	if (prefixcmp(buffer.buf, "emacsclient")) {
+	if (!starts_with(buffer.buf, "emacsclient")) {
 		strbuf_release(&buffer);
 		return error(_("Failed to parse emacsclient version."));
 	}
@@ -258,7 +258,7 @@ static int add_man_viewer_info(const char *var, const char *value)
 
 static int git_help_config(const char *var, const char *value, void *cb)
 {
-	if (!prefixcmp(var, "column."))
+	if (starts_with(var, "column."))
 		return git_column_config(var, value, "help", &colopts);
 	if (!strcmp(var, "help.format")) {
 		if (!value)
@@ -278,7 +278,7 @@ static int git_help_config(const char *var, const char *value, void *cb)
 		add_man_viewer(value);
 		return 0;
 	}
-	if (!prefixcmp(var, "man."))
+	if (starts_with(var, "man."))
 		return add_man_viewer_info(var, value);
 
 	return git_default_config(var, value, cb);
@@ -306,7 +306,7 @@ static const char *cmd_to_page(const char *git_cmd)
 {
 	if (!git_cmd)
 		return "git";
-	else if (!prefixcmp(git_cmd, "git"))
+	else if (starts_with(git_cmd, "git"))
 		return git_cmd;
 	else if (is_git_command(git_cmd))
 		return prepend("git-", git_cmd);
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 9e9eb4b..2f37a38 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -1534,9 +1534,9 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 				stat_only = 1;
 			} else if (!strcmp(arg, "--keep")) {
 				keep_msg = "";
-			} else if (!prefixcmp(arg, "--keep=")) {
+			} else if (starts_with(arg, "--keep=")) {
 				keep_msg = arg + 7;
-			} else if (!prefixcmp(arg, "--threads=")) {
+			} else if (starts_with(arg, "--threads=")) {
 				char *end;
 				nr_threads = strtoul(arg+10, &end, 0);
 				if (!arg[10] || *end || nr_threads < 0)
@@ -1547,7 +1547,7 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 						  "ignoring %s"), arg);
 				nr_threads = 1;
 #endif
-			} else if (!prefixcmp(arg, "--pack_header=")) {
+			} else if (starts_with(arg, "--pack_header=")) {
 				struct pack_header *hdr;
 				char *c;
 
@@ -1566,7 +1566,7 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 				if (index_name || (i+1) >= argc)
 					usage(index_pack_usage);
 				index_name = argv[++i];
-			} else if (!prefixcmp(arg, "--index-version=")) {
+			} else if (starts_with(arg, "--index-version=")) {
 				char *c;
 				opts.version = strtoul(arg + 16, &c, 10);
 				if (opts.version > 2)
diff --git a/builtin/init-db.c b/builtin/init-db.c
index 78aa387..b3f03cf 100644
--- a/builtin/init-db.c
+++ b/builtin/init-db.c
@@ -266,7 +266,7 @@ static int create_default_files(const char *template_path)
 		/* allow template config file to override the default */
 		if (log_all_ref_updates == -1)
 		    git_config_set("core.logallrefupdates", "true");
-		if (prefixcmp(git_dir, work_tree) ||
+		if (!starts_with(git_dir, work_tree) ||
 		    strcmp(git_dir + strlen(work_tree), "/.git")) {
 			git_config_set("core.worktree", work_tree);
 		}
diff --git a/builtin/log.c b/builtin/log.c
index b708517..b97373d 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -391,7 +391,7 @@ static int git_log_config(const char *var, const char *value, void *cb)
 		default_show_root = git_config_bool(var, value);
 		return 0;
 	}
-	if (!prefixcmp(var, "color.decorate."))
+	if (starts_with(var, "color.decorate."))
 		return parse_decorate_color_config(var, 15, value);
 	if (!strcmp(var, "log.mailmap")) {
 		use_mailmap_config = git_config_bool(var, value);
@@ -477,7 +477,7 @@ static int show_tag_object(const unsigned char *sha1, struct rev_info *rev)
 		int new_offset = offset + 1;
 		while (new_offset < size && buf[new_offset++] != '\n')
 			; /* do nothing */
-		if (!prefixcmp(buf + offset, "tagger "))
+		if (starts_with(buf + offset, "tagger "))
 			show_tagger(buf + offset + 7,
 				    new_offset - offset - 7, rev);
 		offset = new_offset;
@@ -882,7 +882,7 @@ static char *find_branch_name(struct rev_info *rev)
 	ref = rev->cmdline.rev[positive].name;
 	tip_sha1 = rev->cmdline.rev[positive].item->sha1;
 	if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
-	    !prefixcmp(full_ref, "refs/heads/") &&
+	    starts_with(full_ref, "refs/heads/") &&
 	    !hashcmp(tip_sha1, branch_sha1))
 		branch = xstrdup(full_ref + strlen("refs/heads/"));
 	free(full_ref);
@@ -1388,7 +1388,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 			unsigned char sha1[20];
 			const char *ref;
 			ref = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
-			if (ref && !prefixcmp(ref, "refs/heads/"))
+			if (ref && starts_with(ref, "refs/heads/"))
 				branch_name = xstrdup(ref + strlen("refs/heads/"));
 			else
 				branch_name = xstrdup(""); /* no branch */
diff --git a/builtin/ls-remote.c b/builtin/ls-remote.c
index 25e83cf..39e5144 100644
--- a/builtin/ls-remote.c
+++ b/builtin/ls-remote.c
@@ -50,11 +50,11 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
 		const char *arg = argv[i];
 
 		if (*arg == '-') {
-			if (!prefixcmp(arg, "--upload-pack=")) {
+			if (starts_with(arg, "--upload-pack=")) {
 				uploadpack = arg + 14;
 				continue;
 			}
-			if (!prefixcmp(arg, "--exec=")) {
+			if (starts_with(arg, "--exec=")) {
 				uploadpack = arg + 7;
 				continue;
 			}
diff --git a/builtin/mailinfo.c b/builtin/mailinfo.c
index 24a772d..2c3cd8e 100644
--- a/builtin/mailinfo.c
+++ b/builtin/mailinfo.c
@@ -328,11 +328,11 @@ static int check_header(const struct strbuf *line,
 	}
 
 	/* for inbody stuff */
-	if (!prefixcmp(line->buf, ">From") && isspace(line->buf[5])) {
+	if (starts_with(line->buf, ">From") && isspace(line->buf[5])) {
 		ret = 1; /* Should this return 0? */
 		goto check_header_out;
 	}
-	if (!prefixcmp(line->buf, "[PATCH]") && isspace(line->buf[7])) {
+	if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
 		for (i = 0; header[i]; i++) {
 			if (!memcmp("Subject", header[i], 7)) {
 				handle_header(&hdr_data[i], line);
@@ -361,7 +361,7 @@ static int is_rfc2822_header(const struct strbuf *line)
 	char *cp = line->buf;
 
 	/* Count mbox From headers as headers */
-	if (!prefixcmp(cp, "From ") || !prefixcmp(cp, ">From "))
+	if (starts_with(cp, "From ") || starts_with(cp, ">From "))
 		return 1;
 
 	while ((ch = *cp++)) {
@@ -671,11 +671,11 @@ static inline int patchbreak(const struct strbuf *line)
 	size_t i;
 
 	/* Beginning of a "diff -" header? */
-	if (!prefixcmp(line->buf, "diff -"))
+	if (starts_with(line->buf, "diff -"))
 		return 1;
 
 	/* CVS "Index: " line? */
-	if (!prefixcmp(line->buf, "Index: "))
+	if (starts_with(line->buf, "Index: "))
 		return 1;
 
 	/*
@@ -685,7 +685,7 @@ static inline int patchbreak(const struct strbuf *line)
 	if (line->len < 4)
 		return 0;
 
-	if (!prefixcmp(line->buf, "---")) {
+	if (starts_with(line->buf, "---")) {
 		/* space followed by a filename? */
 		if (line->buf[3] == ' ' && !isspace(line->buf[4]))
 			return 1;
@@ -986,7 +986,7 @@ static int mailinfo(FILE *in, FILE *out, const char *msg, const char *patch)
 
 static int git_mailinfo_config(const char *var, const char *value, void *unused)
 {
-	if (prefixcmp(var, "mailinfo."))
+	if (!starts_with(var, "mailinfo."))
 		return git_default_config(var, value, unused);
 	if (!strcmp(var, "mailinfo.scissors")) {
 		use_scissors = git_config_bool(var, value);
@@ -1020,7 +1020,7 @@ int cmd_mailinfo(int argc, const char **argv, const char *prefix)
 			metainfo_charset = def_charset;
 		else if (!strcmp(argv[1], "-n"))
 			metainfo_charset = NULL;
-		else if (!prefixcmp(argv[1], "--encoding="))
+		else if (starts_with(argv[1], "--encoding="))
 			metainfo_charset = argv[1] + 11;
 		else if (!strcmp(argv[1], "--scissors"))
 			use_scissors = 1;
diff --git a/builtin/merge-recursive.c b/builtin/merge-recursive.c
index 3a64f5d..a90f28f 100644
--- a/builtin/merge-recursive.c
+++ b/builtin/merge-recursive.c
@@ -29,7 +29,7 @@ int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
 	struct commit *result;
 
 	init_merge_options(&o);
-	if (argv[0] && !suffixcmp(argv[0], "-subtree"))
+	if (argv[0] && ends_with(argv[0], "-subtree"))
 		o.subtree_shift = "";
 
 	if (argc < 4)
@@ -38,7 +38,7 @@ int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
 	for (i = 1; i < argc; ++i) {
 		const char *arg = argv[i];
 
-		if (!prefixcmp(arg, "--")) {
+		if (starts_with(arg, "--")) {
 			if (!arg[2])
 				break;
 			if (parse_merge_opt(&o, arg + 2))
diff --git a/builtin/merge.c b/builtin/merge.c
index 41fb66d..4941a6c 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -446,17 +446,17 @@ static void merge_name(const char *remote, struct strbuf *msg)
 		die(_("'%s' does not point to a commit"), remote);
 
 	if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
-		if (!prefixcmp(found_ref, "refs/heads/")) {
+		if (starts_with(found_ref, "refs/heads/")) {
 			strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
 				    sha1_to_hex(branch_head), remote);
 			goto cleanup;
 		}
-		if (!prefixcmp(found_ref, "refs/tags/")) {
+		if (starts_with(found_ref, "refs/tags/")) {
 			strbuf_addf(msg, "%s\t\ttag '%s' of .\n",
 				    sha1_to_hex(branch_head), remote);
 			goto cleanup;
 		}
-		if (!prefixcmp(found_ref, "refs/remotes/")) {
+		if (starts_with(found_ref, "refs/remotes/")) {
 			strbuf_addf(msg, "%s\t\tremote-tracking branch '%s' of .\n",
 				    sha1_to_hex(branch_head), remote);
 			goto cleanup;
@@ -570,8 +570,8 @@ static int git_merge_config(const char *k, const char *v, void *cb)
 {
 	int status;
 
-	if (branch && !prefixcmp(k, "branch.") &&
-		!prefixcmp(k + 7, branch) &&
+	if (branch && starts_with(k, "branch.") &&
+		starts_with(k + 7, branch) &&
 		!strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
 		free(branch_mergeoptions);
 		branch_mergeoptions = xstrdup(v);
@@ -1106,7 +1106,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 	 * current branch.
 	 */
 	branch = branch_to_free = resolve_refdup("HEAD", head_sha1, 0, &flag);
-	if (branch && !prefixcmp(branch, "refs/heads/"))
+	if (branch && starts_with(branch, "refs/heads/"))
 		branch += 11;
 	if (!branch || is_null_sha1(head_sha1))
 		head_commit = NULL;
diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index 20fcf8c..9903901 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -101,9 +101,9 @@ static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
 {
 	if (shorten_unambiguous)
 		refname = shorten_unambiguous_ref(refname, 0);
-	else if (!prefixcmp(refname, "refs/heads/"))
+	else if (starts_with(refname, "refs/heads/"))
 		refname = refname + 11;
-	else if (!prefixcmp(refname, "refs/"))
+	else if (starts_with(refname, "refs/"))
 		refname = refname + 5;
 	return refname;
 }
@@ -149,7 +149,7 @@ static int name_ref(const char *path, const unsigned char *sha1, int flags, void
 	int can_abbreviate_output = data->tags_only && data->name_only;
 	int deref = 0;
 
-	if (data->tags_only && prefixcmp(path, "refs/tags/"))
+	if (data->tags_only && !starts_with(path, "refs/tags/"))
 		return 0;
 
 	if (data->ref_filter) {
diff --git a/builtin/notes.c b/builtin/notes.c
index d459e23..2b24d05 100644
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -347,7 +347,7 @@ static struct notes_tree *init_notes_check(const char *subcommand)
 	init_notes(NULL, NULL, NULL, 0);
 	t = &default_notes_tree;
 
-	if (prefixcmp(t->ref, "refs/notes/"))
+	if (!starts_with(t->ref, "refs/notes/"))
 		die("Refusing to %s notes in %s (outside of refs/notes/)",
 		    subcommand, t->ref);
 	return t;
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 36273dd..dfb4d84 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -2032,7 +2032,7 @@ static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, vo
 {
 	unsigned char peeled[20];
 
-	if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
+	if (starts_with(path, "refs/tags/") && /* is a tag? */
 	    !peel_ref(path, peeled)        && /* peelable? */
 	    locate_object_entry(peeled))      /* object packed? */
 		add_object_entry(sha1, OBJ_TAG, NULL, 0);
diff --git a/builtin/prune.c b/builtin/prune.c
index 6366917..a85ef54 100644
--- a/builtin/prune.c
+++ b/builtin/prune.c
@@ -80,7 +80,7 @@ static int prune_dir(int i, char *path)
 			prune_object(path, de->d_name, sha1);
 			continue;
 		}
-		if (!prefixcmp(de->d_name, "tmp_obj_")) {
+		if (starts_with(de->d_name, "tmp_obj_")) {
 			prune_tmp_object(path, de->d_name);
 			continue;
 		}
@@ -119,7 +119,7 @@ static void remove_temporary_files(const char *path)
 		return;
 	}
 	while ((de = readdir(dir)) != NULL)
-		if (!prefixcmp(de->d_name, "tmp_"))
+		if (starts_with(de->d_name, "tmp_"))
 			prune_tmp_object(path, de->d_name);
 	closedir(dir);
 }
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 67ce1ef..e09994f 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -428,7 +428,7 @@ static const char *update(struct command *cmd)
 	struct ref_lock *lock;
 
 	/* only refs/... are allowed */
-	if (prefixcmp(name, "refs/") || check_refname_format(name + 5, 0)) {
+	if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
 		rp_error("refusing to create funny ref '%s' remotely", name);
 		return "funny refname";
 	}
@@ -459,7 +459,7 @@ static const char *update(struct command *cmd)
 	}
 
 	if (!is_null_sha1(old_sha1) && is_null_sha1(new_sha1)) {
-		if (deny_deletes && !prefixcmp(name, "refs/heads/")) {
+		if (deny_deletes && starts_with(name, "refs/heads/")) {
 			rp_error("denying ref deletion for %s", name);
 			return "deletion prohibited";
 		}
@@ -483,7 +483,7 @@ static const char *update(struct command *cmd)
 
 	if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 	    !is_null_sha1(old_sha1) &&
-	    !prefixcmp(name, "refs/heads/")) {
+	    starts_with(name, "refs/heads/")) {
 		struct object *old_object, *new_object;
 		struct commit *old_commit, *new_commit;
 
diff --git a/builtin/reflog.c b/builtin/reflog.c
index 6eb24c8..852cff6 100644
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -610,12 +610,12 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
 		const char *arg = argv[i];
 		if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
 			cb.dry_run = 1;
-		else if (!prefixcmp(arg, "--expire=")) {
+		else if (starts_with(arg, "--expire=")) {
 			if (parse_expiry_date(arg + 9, &cb.expire_total))
 				die(_("'%s' is not a valid timestamp"), arg);
 			explicit_expiry |= EXPIRE_TOTAL;
 		}
-		else if (!prefixcmp(arg, "--expire-unreachable=")) {
+		else if (starts_with(arg, "--expire-unreachable=")) {
 			if (parse_expiry_date(arg + 21, &cb.expire_unreachable))
 				die(_("'%s' is not a valid timestamp"), arg);
 			explicit_expiry |= EXPIRE_UNREACH;
diff --git a/builtin/remote.c b/builtin/remote.c
index 9b3a98e..b3fd92f 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -261,7 +261,7 @@ static const char *abbrev_ref(const char *name, const char *prefix)
 
 static int config_read_branches(const char *key, const char *value, void *cb)
 {
-	if (!prefixcmp(key, "branch.")) {
+	if (starts_with(key, "branch.")) {
 		const char *orig_key = key;
 		char *name;
 		struct string_list_item *item;
@@ -269,13 +269,13 @@ static int config_read_branches(const char *key, const char *value, void *cb)
 		enum { REMOTE, MERGE, REBASE } type;
 
 		key += 7;
-		if (!suffixcmp(key, ".remote")) {
+		if (ends_with(key, ".remote")) {
 			name = xstrndup(key, strlen(key) - 7);
 			type = REMOTE;
-		} else if (!suffixcmp(key, ".merge")) {
+		} else if (ends_with(key, ".merge")) {
 			name = xstrndup(key, strlen(key) - 6);
 			type = MERGE;
-		} else if (!suffixcmp(key, ".rebase")) {
+		} else if (ends_with(key, ".rebase")) {
 			name = xstrndup(key, strlen(key) - 7);
 			type = REBASE;
 		} else
@@ -526,9 +526,9 @@ static int add_branch_for_removal(const char *refname,
 	}
 
 	/* don't delete non-remote-tracking refs */
-	if (prefixcmp(refname, "refs/remotes/")) {
+	if (!starts_with(refname, "refs/remotes/")) {
 		/* advise user how to delete local branches */
-		if (!prefixcmp(refname, "refs/heads/"))
+		if (starts_with(refname, "refs/heads/"))
 			string_list_append(branches->skipped,
 					   abbrev_branch(refname));
 		/* silently skip over other non-remote refs */
@@ -563,7 +563,7 @@ static int read_remote_branches(const char *refname,
 	const char *symref;
 
 	strbuf_addf(&buf, "refs/remotes/%s/", rename->old);
-	if (!prefixcmp(refname, buf.buf)) {
+	if (starts_with(refname, buf.buf)) {
 		item = string_list_append(rename->remote_branches, xstrdup(refname));
 		symref = resolve_ref_unsafe(refname, orig_sha1, 1, &flag);
 		if (flag & REF_ISSYMREF)
diff --git a/builtin/repack.c b/builtin/repack.c
index a0ff5c7..938bc75 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -78,7 +78,7 @@ static void get_non_kept_pack_filenames(struct string_list *fname_list)
 		return;
 
 	while ((e = readdir(dir)) != NULL) {
-		if (suffixcmp(e->d_name, ".pack"))
+		if (!ends_with(e->d_name, ".pack"))
 			continue;
 
 		len = strlen(e->d_name) - strlen(".pack");
diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index c76b89d..6b89402 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@@ -508,7 +508,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 			}
 			continue;
 		}
-		if (!prefixcmp(arg, "-n")) {
+		if (starts_with(arg, "-n")) {
 			if ((filter & DO_FLAGS) && (filter & DO_REVS))
 				show(arg);
 			continue;
@@ -560,7 +560,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				continue;
 			}
 			if (!strcmp(arg, "--short") ||
-			    !prefixcmp(arg, "--short=")) {
+			    starts_with(arg, "--short=")) {
 				filter &= ~(DO_FLAGS|DO_NOREV);
 				verify = 1;
 				abbrev = DEFAULT_ABBREV;
@@ -588,7 +588,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				symbolic = SHOW_SYMBOLIC_FULL;
 				continue;
 			}
-			if (!prefixcmp(arg, "--abbrev-ref") &&
+			if (starts_with(arg, "--abbrev-ref") &&
 			    (!arg[12] || arg[12] == '=')) {
 				abbrev_ref = 1;
 				abbrev_ref_strict = warn_ambiguous_refs;
@@ -606,7 +606,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_ref(show_reference, NULL);
 				continue;
 			}
-			if (!prefixcmp(arg, "--disambiguate=")) {
+			if (starts_with(arg, "--disambiguate=")) {
 				for_each_abbrev(arg + 15, show_abbrev, NULL);
 				continue;
 			}
@@ -615,7 +615,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_ref_in("refs/bisect/good", anti_reference, NULL);
 				continue;
 			}
-			if (!prefixcmp(arg, "--branches=")) {
+			if (starts_with(arg, "--branches=")) {
 				for_each_glob_ref_in(show_reference, arg + 11,
 					"refs/heads/", NULL);
 				continue;
@@ -624,7 +624,7 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_branch_ref(show_reference, NULL);
 				continue;
 			}
-			if (!prefixcmp(arg, "--tags=")) {
+			if (starts_with(arg, "--tags=")) {
 				for_each_glob_ref_in(show_reference, arg + 7,
 					"refs/tags/", NULL);
 				continue;
@@ -633,11 +633,11 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				for_each_tag_ref(show_reference, NULL);
 				continue;
 			}
-			if (!prefixcmp(arg, "--glob=")) {
+			if (starts_with(arg, "--glob=")) {
 				for_each_glob_ref(show_reference, arg + 7, NULL);
 				continue;
 			}
-			if (!prefixcmp(arg, "--remotes=")) {
+			if (starts_with(arg, "--remotes=")) {
 				for_each_glob_ref_in(show_reference, arg + 10,
 					"refs/remotes/", NULL);
 				continue;
@@ -724,19 +724,19 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 						: "false");
 				continue;
 			}
-			if (!prefixcmp(arg, "--since=")) {
+			if (starts_with(arg, "--since=")) {
 				show_datestring("--max-age=", arg+8);
 				continue;
 			}
-			if (!prefixcmp(arg, "--after=")) {
+			if (starts_with(arg, "--after=")) {
 				show_datestring("--max-age=", arg+8);
 				continue;
 			}
-			if (!prefixcmp(arg, "--before=")) {
+			if (starts_with(arg, "--before=")) {
 				show_datestring("--min-age=", arg+9);
 				continue;
 			}
-			if (!prefixcmp(arg, "--until=")) {
+			if (starts_with(arg, "--until=")) {
 				show_datestring("--min-age=", arg+8);
 				continue;
 			}
diff --git a/builtin/send-pack.c b/builtin/send-pack.c
index 4482f16..e7f0b97 100644
--- a/builtin/send-pack.c
+++ b/builtin/send-pack.c
@@ -115,15 +115,15 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
 		const char *arg = *argv;
 
 		if (*arg == '-') {
-			if (!prefixcmp(arg, "--receive-pack=")) {
+			if (starts_with(arg, "--receive-pack=")) {
 				receivepack = arg + 15;
 				continue;
 			}
-			if (!prefixcmp(arg, "--exec=")) {
+			if (starts_with(arg, "--exec=")) {
 				receivepack = arg + 7;
 				continue;
 			}
-			if (!prefixcmp(arg, "--remote=")) {
+			if (starts_with(arg, "--remote=")) {
 				remote_name = arg + 9;
 				continue;
 			}
@@ -181,7 +181,7 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
 					exit(1);
 				continue;
 			}
-			if (!prefixcmp(arg, "--" CAS_OPT_NAME "=")) {
+			if (starts_with(arg, "--" CAS_OPT_NAME "=")) {
 				if (parse_push_cas_option(&cas,
 							  strchr(arg, '=') + 1, 0) < 0)
 					exit(1);
diff --git a/builtin/shortlog.c b/builtin/shortlog.c
index c226f76..4b7e536 100644
--- a/builtin/shortlog.c
+++ b/builtin/shortlog.c
@@ -65,7 +65,7 @@ static void insert_one_record(struct shortlog *log,
 	eol = strchr(oneline, '\n');
 	if (!eol)
 		eol = oneline + strlen(oneline);
-	if (!prefixcmp(oneline, "[PATCH")) {
+	if (starts_with(oneline, "[PATCH")) {
 		char *eob = strchr(oneline, ']');
 		if (eob && (!eol || eob < eol))
 			oneline = eob + 1;
@@ -95,7 +95,7 @@ static void read_from_stdin(struct shortlog *log)
 
 	while (fgets(author, sizeof(author), stdin) != NULL) {
 		if (!(author[0] == 'A' || author[0] == 'a') ||
-		    prefixcmp(author + 1, "uthor: "))
+		    !starts_with(author + 1, "uthor: "))
 			continue;
 		while (fgets(oneline, sizeof(oneline), stdin) &&
 		       oneline[0] != '\n')
@@ -123,7 +123,7 @@ void shortlog_add_commit(struct shortlog *log, struct commit *commit)
 		else
 			eol++;
 
-		if (!prefixcmp(buffer, "author "))
+		if (starts_with(buffer, "author "))
 			author = buffer + 7;
 		buffer = eol;
 	}
diff --git a/builtin/show-branch.c b/builtin/show-branch.c
index 001f29c..f20c274 100644
--- a/builtin/show-branch.c
+++ b/builtin/show-branch.c
@@ -285,7 +285,7 @@ static void show_one_commit(struct commit *commit, int no_name)
 		pp_commit_easy(CMIT_FMT_ONELINE, commit, &pretty);
 		pretty_str = pretty.buf;
 	}
-	if (!prefixcmp(pretty_str, "[PATCH] "))
+	if (starts_with(pretty_str, "[PATCH] "))
 		pretty_str += 8;
 
 	if (!no_name) {
@@ -396,7 +396,7 @@ static int append_head_ref(const char *refname, const unsigned char *sha1, int f
 {
 	unsigned char tmp[20];
 	int ofs = 11;
-	if (prefixcmp(refname, "refs/heads/"))
+	if (!starts_with(refname, "refs/heads/"))
 		return 0;
 	/* If both heads/foo and tags/foo exists, get_sha1 would
 	 * get confused.
@@ -410,7 +410,7 @@ static int append_remote_ref(const char *refname, const unsigned char *sha1, int
 {
 	unsigned char tmp[20];
 	int ofs = 13;
-	if (prefixcmp(refname, "refs/remotes/"))
+	if (!starts_with(refname, "refs/remotes/"))
 		return 0;
 	/* If both heads/foo and tags/foo exists, get_sha1 would
 	 * get confused.
@@ -422,7 +422,7 @@ static int append_remote_ref(const char *refname, const unsigned char *sha1, int
 
 static int append_tag_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 {
-	if (prefixcmp(refname, "refs/tags/"))
+	if (!starts_with(refname, "refs/tags/"))
 		return 0;
 	return append_ref(refname + 5, sha1, 0);
 }
@@ -453,9 +453,9 @@ static int append_matching_ref(const char *refname, const unsigned char *sha1, i
 		return 0;
 	if (fnmatch(match_ref_pattern, tail, 0))
 		return 0;
-	if (!prefixcmp(refname, "refs/heads/"))
+	if (starts_with(refname, "refs/heads/"))
 		return append_head_ref(refname, sha1, flag, cb_data);
-	if (!prefixcmp(refname, "refs/tags/"))
+	if (starts_with(refname, "refs/tags/"))
 		return append_tag_ref(refname, sha1, flag, cb_data);
 	return append_ref(refname, sha1, 0);
 }
@@ -480,11 +480,11 @@ static int rev_is_head(char *head, int headlen, char *name,
 	if ((!head[0]) ||
 	    (head_sha1 && sha1 && hashcmp(head_sha1, sha1)))
 		return 0;
-	if (!prefixcmp(head, "refs/heads/"))
+	if (starts_with(head, "refs/heads/"))
 		head += 11;
-	if (!prefixcmp(name, "refs/heads/"))
+	if (starts_with(name, "refs/heads/"))
 		name += 11;
-	else if (!prefixcmp(name, "heads/"))
+	else if (starts_with(name, "heads/"))
 		name += 6;
 	return !strcmp(head, name);
 }
@@ -813,7 +813,7 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 				has_head++;
 		}
 		if (!has_head) {
-			int offset = !prefixcmp(head, "refs/heads/") ? 11 : 0;
+			int offset = starts_with(head, "refs/heads/") ? 11 : 0;
 			append_one_rev(head + offset);
 		}
 	}
diff --git a/builtin/show-ref.c b/builtin/show-ref.c
index 9f3f5e3..5ba1f30 100644
--- a/builtin/show-ref.c
+++ b/builtin/show-ref.c
@@ -37,8 +37,8 @@ static int show_ref(const char *refname, const unsigned char *sha1, int flag, vo
 	if (tags_only || heads_only) {
 		int match;
 
-		match = heads_only && !prefixcmp(refname, "refs/heads/");
-		match |= tags_only && !prefixcmp(refname, "refs/tags/");
+		match = heads_only && starts_with(refname, "refs/heads/");
+		match |= tags_only && starts_with(refname, "refs/tags/");
 		if (!match)
 			return 0;
 	}
@@ -210,7 +210,7 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix)
 		while (*pattern) {
 			unsigned char sha1[20];
 
-			if (!prefixcmp(*pattern, "refs/") &&
+			if (starts_with(*pattern, "refs/") &&
 			    !read_ref(*pattern, sha1)) {
 				if (!quiet)
 					show_one(*pattern, sha1);
diff --git a/builtin/symbolic-ref.c b/builtin/symbolic-ref.c
index 71286b4..b6a711d 100644
--- a/builtin/symbolic-ref.c
+++ b/builtin/symbolic-ref.c
@@ -65,7 +65,7 @@ int cmd_symbolic_ref(int argc, const char **argv, const char *prefix)
 		break;
 	case 2:
 		if (!strcmp(argv[0], "HEAD") &&
-		    prefixcmp(argv[1], "refs/"))
+		    !starts_with(argv[1], "refs/"))
 			die("Refusing to point HEAD outside of refs/");
 		create_symref(argv[0], argv[1], msg);
 		break;
diff --git a/builtin/tag.c b/builtin/tag.c
index ea55f1d..74d3780 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -259,7 +259,7 @@ static int git_tag_config(const char *var, const char *value, void *cb)
 	int status = git_gpg_config(var, value, cb);
 	if (status)
 		return status;
-	if (!prefixcmp(var, "column."))
+	if (starts_with(var, "column."))
 		return git_column_config(var, value, "tag", &colopts);
 	return git_default_config(var, value, cb);
 }
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index 2217d7b..62ff673 100644
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -523,7 +523,7 @@ int cmd_unpack_objects(int argc, const char **argv, const char *prefix)
 				strict = 1;
 				continue;
 			}
-			if (!prefixcmp(arg, "--pack_header=")) {
+			if (starts_with(arg, "--pack_header=")) {
 				struct pack_header *hdr;
 				char *c;
 
diff --git a/builtin/update-ref.c b/builtin/update-ref.c
index 702e90d..1292cfe 100644
--- a/builtin/update-ref.c
+++ b/builtin/update-ref.c
@@ -229,15 +229,15 @@ static void update_refs_stdin(void)
 			die("empty command in input");
 		else if (isspace(*cmd.buf))
 			die("whitespace before command: %s", cmd.buf);
-		else if (!prefixcmp(cmd.buf, "update "))
+		else if (starts_with(cmd.buf, "update "))
 			parse_cmd_update(cmd.buf + 7);
-		else if (!prefixcmp(cmd.buf, "create "))
+		else if (starts_with(cmd.buf, "create "))
 			parse_cmd_create(cmd.buf + 7);
-		else if (!prefixcmp(cmd.buf, "delete "))
+		else if (starts_with(cmd.buf, "delete "))
 			parse_cmd_delete(cmd.buf + 7);
-		else if (!prefixcmp(cmd.buf, "verify "))
+		else if (starts_with(cmd.buf, "verify "))
 			parse_cmd_verify(cmd.buf + 7);
-		else if (!prefixcmp(cmd.buf, "option "))
+		else if (starts_with(cmd.buf, "option "))
 			parse_cmd_option(cmd.buf + 7);
 		else
 			die("unknown command: %s", cmd.buf);
diff --git a/builtin/upload-archive.c b/builtin/upload-archive.c
index af2da35..32ab94c 100644
--- a/builtin/upload-archive.c
+++ b/builtin/upload-archive.c
@@ -37,7 +37,7 @@ int cmd_upload_archive_writer(int argc, const char **argv, const char *prefix)
 		if (sent_argv.argc > MAX_ARGS)
 			die("Too many options (>%d)", MAX_ARGS - 1);
 
-		if (prefixcmp(buf, arg_cmd))
+		if (!starts_with(buf, arg_cmd))
 			die("'argument' token or flush expected");
 		argv_array_push(&sent_argv, buf + strlen(arg_cmd));
 	}
diff --git a/commit.c b/commit.c
index de16a3c..2a9bf59 100644
--- a/commit.c
+++ b/commit.c
@@ -559,7 +559,7 @@ static void record_author_date(struct author_date_slab *author_date,
 	     buf;
 	     buf = line_end + 1) {
 		line_end = strchrnul(buf, '\n');
-		if (prefixcmp(buf, "author ")) {
+		if (!starts_with(buf, "author ")) {
 			if (!line_end[0] || line_end[1] == '\n')
 				return; /* end of header */
 			continue;
@@ -1106,7 +1106,7 @@ int parse_signed_commit(const unsigned char *sha1,
 		next = next ? next + 1 : tail;
 		if (in_signature && line[0] == ' ')
 			sig = line + 1;
-		else if (!prefixcmp(line, gpg_sig_header) &&
+		else if (starts_with(line, gpg_sig_header) &&
 			 line[gpg_sig_header_len] == ' ')
 			sig = line + gpg_sig_header_len + 1;
 		if (sig) {
@@ -1186,7 +1186,7 @@ static void parse_gpg_output(struct signature_check *sigc)
 	for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
 		const char *found, *next;
 
-		if (!prefixcmp(buf, sigcheck_gpg_status[i].check + 1)) {
+		if (starts_with(buf, sigcheck_gpg_status[i].check + 1)) {
 			/* At the very beginning of the buffer */
 			found = buf + strlen(sigcheck_gpg_status[i].check + 1);
 		} else {
diff --git a/config.c b/config.c
index e1d66a1..7b62f33 100644
--- a/config.c
+++ b/config.c
@@ -969,25 +969,25 @@ static int git_default_mailmap_config(const char *var, const char *value)
 
 int git_default_config(const char *var, const char *value, void *dummy)
 {
-	if (!prefixcmp(var, "core."))
+	if (starts_with(var, "core."))
 		return git_default_core_config(var, value);
 
-	if (!prefixcmp(var, "user."))
+	if (starts_with(var, "user."))
 		return git_ident_config(var, value, dummy);
 
-	if (!prefixcmp(var, "i18n."))
+	if (starts_with(var, "i18n."))
 		return git_default_i18n_config(var, value);
 
-	if (!prefixcmp(var, "branch."))
+	if (starts_with(var, "branch."))
 		return git_default_branch_config(var, value);
 
-	if (!prefixcmp(var, "push."))
+	if (starts_with(var, "push."))
 		return git_default_push_config(var, value);
 
-	if (!prefixcmp(var, "mailmap."))
+	if (starts_with(var, "mailmap."))
 		return git_default_mailmap_config(var, value);
 
-	if (!prefixcmp(var, "advice."))
+	if (starts_with(var, "advice."))
 		return git_default_advice_config(var, value);
 
 	if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
@@ -1872,7 +1872,7 @@ int parse_config_key(const char *var,
 	const char *dot;
 
 	/* Does it start with "section." ? */
-	if (prefixcmp(var, section) || var[section_len] != '.')
+	if (!starts_with(var, section) || var[section_len] != '.')
 		return -1;
 
 	/*
diff --git a/connect.c b/connect.c
index 06e88b0..d51d106 100644
--- a/connect.c
+++ b/connect.c
@@ -145,7 +145,7 @@ struct ref **get_remote_heads(int in, char *src_buf, size_t src_len,
 		if (!len)
 			break;
 
-		if (len > 4 && !prefixcmp(buffer, "ERR "))
+		if (len > 4 && starts_with(buffer, "ERR "))
 			die("remote error: %s", buffer + 4);
 
 		if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
diff --git a/connected.c b/connected.c
index fae8d64..51d8ba4 100644
--- a/connected.c
+++ b/connected.c
@@ -38,7 +38,7 @@ int check_everything_connected_with_transport(sha1_iterate_fn fn,
 	if (transport && transport->smart_options &&
 	    transport->smart_options->self_contained_and_connected &&
 	    transport->pack_lockfile &&
-	    !suffixcmp(transport->pack_lockfile, ".keep")) {
+	    ends_with(transport->pack_lockfile, ".keep")) {
 		struct strbuf idx_file = STRBUF_INIT;
 		strbuf_addstr(&idx_file, transport->pack_lockfile);
 		strbuf_setlen(&idx_file, idx_file.len - 5); /* ".keep" */
diff --git a/convert.c b/convert.c
index 11a95fc..ab80b72 100644
--- a/convert.c
+++ b/convert.c
@@ -1121,7 +1121,7 @@ static int is_foreign_ident(const char *str)
 {
 	int i;
 
-	if (prefixcmp(str, "$Id: "))
+	if (!starts_with(str, "$Id: "))
 		return 0;
 	for (i = 5; str[i]; i++) {
 		if (isspace(str[i]) && str[i+1] != '$')
diff --git a/daemon.c b/daemon.c
index 34916c5..7bee953 100644
--- a/daemon.c
+++ b/daemon.c
@@ -235,7 +235,7 @@ static int service_enabled;
 
 static int git_daemon_config(const char *var, const char *value, void *cb)
 {
-	if (!prefixcmp(var, "daemon.") &&
+	if (starts_with(var, "daemon.") &&
 	    !strcmp(var + 7, service_looking_at->config_name)) {
 		service_enabled = git_config_bool(var, value);
 		return 0;
@@ -633,7 +633,7 @@ static int execute(void)
 	for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
 		struct daemon_service *s = &(daemon_service[i]);
 		int namelen = strlen(s->name);
-		if (!prefixcmp(line, "git-") &&
+		if (starts_with(line, "git-") &&
 		    !strncmp(s->name, line + 4, namelen) &&
 		    line[namelen + 4] == ' ') {
 			/*
@@ -1165,11 +1165,11 @@ int main(int argc, char **argv)
 	for (i = 1; i < argc; i++) {
 		char *arg = argv[i];
 
-		if (!prefixcmp(arg, "--listen=")) {
+		if (starts_with(arg, "--listen=")) {
 			string_list_append(&listen_addr, xstrdup_tolower(arg + 9));
 			continue;
 		}
-		if (!prefixcmp(arg, "--port=")) {
+		if (starts_with(arg, "--port=")) {
 			char *end;
 			unsigned long n;
 			n = strtoul(arg+7, &end, 0);
@@ -1199,19 +1199,19 @@ int main(int argc, char **argv)
 			export_all_trees = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--access-hook=")) {
+		if (starts_with(arg, "--access-hook=")) {
 			access_hook = arg + 14;
 			continue;
 		}
-		if (!prefixcmp(arg, "--timeout=")) {
+		if (starts_with(arg, "--timeout=")) {
 			timeout = atoi(arg+10);
 			continue;
 		}
-		if (!prefixcmp(arg, "--init-timeout=")) {
+		if (starts_with(arg, "--init-timeout=")) {
 			init_timeout = atoi(arg+15);
 			continue;
 		}
-		if (!prefixcmp(arg, "--max-connections=")) {
+		if (starts_with(arg, "--max-connections=")) {
 			max_connections = atoi(arg+18);
 			if (max_connections < 0)
 				max_connections = 0;	        /* unlimited */
@@ -1221,7 +1221,7 @@ int main(int argc, char **argv)
 			strict_paths = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--base-path=")) {
+		if (starts_with(arg, "--base-path=")) {
 			base_path = arg+12;
 			continue;
 		}
@@ -1229,7 +1229,7 @@ int main(int argc, char **argv)
 			base_path_relaxed = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--interpolated-path=")) {
+		if (starts_with(arg, "--interpolated-path=")) {
 			interpolated_path = arg+20;
 			continue;
 		}
@@ -1241,11 +1241,11 @@ int main(int argc, char **argv)
 			user_path = "";
 			continue;
 		}
-		if (!prefixcmp(arg, "--user-path=")) {
+		if (starts_with(arg, "--user-path=")) {
 			user_path = arg + 12;
 			continue;
 		}
-		if (!prefixcmp(arg, "--pid-file=")) {
+		if (starts_with(arg, "--pid-file=")) {
 			pid_file = arg + 11;
 			continue;
 		}
@@ -1254,35 +1254,35 @@ int main(int argc, char **argv)
 			log_syslog = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--user=")) {
+		if (starts_with(arg, "--user=")) {
 			user_name = arg + 7;
 			continue;
 		}
-		if (!prefixcmp(arg, "--group=")) {
+		if (starts_with(arg, "--group=")) {
 			group_name = arg + 8;
 			continue;
 		}
-		if (!prefixcmp(arg, "--enable=")) {
+		if (starts_with(arg, "--enable=")) {
 			enable_service(arg + 9, 1);
 			continue;
 		}
-		if (!prefixcmp(arg, "--disable=")) {
+		if (starts_with(arg, "--disable=")) {
 			enable_service(arg + 10, 0);
 			continue;
 		}
-		if (!prefixcmp(arg, "--allow-override=")) {
+		if (starts_with(arg, "--allow-override=")) {
 			make_service_overridable(arg + 17, 1);
 			continue;
 		}
-		if (!prefixcmp(arg, "--forbid-override=")) {
+		if (starts_with(arg, "--forbid-override=")) {
 			make_service_overridable(arg + 18, 0);
 			continue;
 		}
-		if (!prefixcmp(arg, "--informative-errors")) {
+		if (starts_with(arg, "--informative-errors")) {
 			informative_errors = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--no-informative-errors")) {
+		if (starts_with(arg, "--no-informative-errors")) {
 			informative_errors = 0;
 			continue;
 		}
diff --git a/diff.c b/diff.c
index e34bf97..d53029b 100644
--- a/diff.c
+++ b/diff.c
@@ -235,7 +235,7 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
 	if (userdiff_config(var, value) < 0)
 		return -1;
 
-	if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
+	if (starts_with(var, "diff.color.") || starts_with(var, "color.diff.")) {
 		int slot = parse_diff_color_slot(var, 11);
 		if (slot < 0)
 			return 0;
@@ -264,7 +264,7 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
 		return 0;
 	}
 
-	if (!prefixcmp(var, "submodule."))
+	if (starts_with(var, "submodule."))
 		return parse_submodule_config_option(var, value);
 
 	return git_default_config(var, value, cb);
@@ -1215,7 +1215,7 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			diff_words_append(line, len,
 					  &ecbdata->diff_words->plus);
 			return;
-		} else if (!prefixcmp(line, "\\ ")) {
+		} else if (starts_with(line, "\\ ")) {
 			/*
 			 * Eat the "no newline at eof" marker as if we
 			 * saw a "+" or "-" line with nothing on it,
@@ -2387,9 +2387,9 @@ static void builtin_diff(const char *name_a,
 			xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
 		if (!diffopts)
 			;
-		else if (!prefixcmp(diffopts, "--unified="))
+		else if (starts_with(diffopts, "--unified="))
 			xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
-		else if (!prefixcmp(diffopts, "-u"))
+		else if (starts_with(diffopts, "-u"))
 			xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
 		if (o->word_diff)
 			init_diff_words_data(&ecbdata, o, one, two);
@@ -3391,7 +3391,7 @@ int parse_long_opt(const char *opt, const char **argv,
 	if (arg[0] != '-' || arg[1] != '-')
 		return 0;
 	arg += strlen("--");
-	if (prefixcmp(arg, opt))
+	if (!starts_with(arg, opt))
 		return 0;
 	arg += strlen(opt);
 	if (*arg == '=') { /* sticked form: --option=value */
@@ -3422,7 +3422,7 @@ static int stat_opt(struct diff_options *options, const char **av)
 
 	switch (*arg) {
 	case '-':
-		if (!prefixcmp(arg, "-width")) {
+		if (starts_with(arg, "-width")) {
 			arg += strlen("-width");
 			if (*arg == '=')
 				width = strtoul(arg + 1, &end, 10);
@@ -3432,7 +3432,7 @@ static int stat_opt(struct diff_options *options, const char **av)
 				width = strtoul(av[1], &end, 10);
 				argcount = 2;
 			}
-		} else if (!prefixcmp(arg, "-name-width")) {
+		} else if (starts_with(arg, "-name-width")) {
 			arg += strlen("-name-width");
 			if (*arg == '=')
 				name_width = strtoul(arg + 1, &end, 10);
@@ -3442,7 +3442,7 @@ static int stat_opt(struct diff_options *options, const char **av)
 				name_width = strtoul(av[1], &end, 10);
 				argcount = 2;
 			}
-		} else if (!prefixcmp(arg, "-graph-width")) {
+		} else if (starts_with(arg, "-graph-width")) {
 			arg += strlen("-graph-width");
 			if (*arg == '=')
 				graph_width = strtoul(arg + 1, &end, 10);
@@ -3452,7 +3452,7 @@ static int stat_opt(struct diff_options *options, const char **av)
 				graph_width = strtoul(av[1], &end, 10);
 				argcount = 2;
 			}
-		} else if (!prefixcmp(arg, "-count")) {
+		} else if (starts_with(arg, "-count")) {
 			arg += strlen("-count");
 			if (*arg == '=')
 				count = strtoul(arg + 1, &end, 10);
@@ -3614,15 +3614,15 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->output_format |= DIFF_FORMAT_SHORTSTAT;
 	else if (!strcmp(arg, "-X") || !strcmp(arg, "--dirstat"))
 		return parse_dirstat_opt(options, "");
-	else if (!prefixcmp(arg, "-X"))
+	else if (starts_with(arg, "-X"))
 		return parse_dirstat_opt(options, arg + 2);
-	else if (!prefixcmp(arg, "--dirstat="))
+	else if (starts_with(arg, "--dirstat="))
 		return parse_dirstat_opt(options, arg + 10);
 	else if (!strcmp(arg, "--cumulative"))
 		return parse_dirstat_opt(options, "cumulative");
 	else if (!strcmp(arg, "--dirstat-by-file"))
 		return parse_dirstat_opt(options, "files");
-	else if (!prefixcmp(arg, "--dirstat-by-file=")) {
+	else if (starts_with(arg, "--dirstat-by-file=")) {
 		parse_dirstat_opt(options, "files");
 		return parse_dirstat_opt(options, arg + 18);
 	}
@@ -3639,17 +3639,17 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->output_format |= DIFF_FORMAT_NAME_STATUS;
 	else if (!strcmp(arg, "-s") || !strcmp(arg, "--no-patch"))
 		options->output_format |= DIFF_FORMAT_NO_OUTPUT;
-	else if (!prefixcmp(arg, "--stat"))
+	else if (starts_with(arg, "--stat"))
 		/* --stat, --stat-width, --stat-name-width, or --stat-count */
 		return stat_opt(options, av);
 
 	/* renames options */
-	else if (!prefixcmp(arg, "-B") || !prefixcmp(arg, "--break-rewrites=") ||
+	else if (starts_with(arg, "-B") || starts_with(arg, "--break-rewrites=") ||
 		 !strcmp(arg, "--break-rewrites")) {
 		if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
 			return error("invalid argument to -B: %s", arg+2);
 	}
-	else if (!prefixcmp(arg, "-M") || !prefixcmp(arg, "--find-renames=") ||
+	else if (starts_with(arg, "-M") || starts_with(arg, "--find-renames=") ||
 		 !strcmp(arg, "--find-renames")) {
 		if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
 			return error("invalid argument to -M: %s", arg+2);
@@ -3658,7 +3658,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 	else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
 		options->irreversible_delete = 1;
 	}
-	else if (!prefixcmp(arg, "-C") || !prefixcmp(arg, "--find-copies=") ||
+	else if (starts_with(arg, "-C") || starts_with(arg, "--find-copies=") ||
 		 !strcmp(arg, "--find-copies")) {
 		if (options->detect_rename == DIFF_DETECT_COPY)
 			DIFF_OPT_SET(options, FIND_COPIES_HARDER);
@@ -3674,7 +3674,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, RENAME_EMPTY);
 	else if (!strcmp(arg, "--relative"))
 		DIFF_OPT_SET(options, RELATIVE_NAME);
-	else if (!prefixcmp(arg, "--relative=")) {
+	else if (starts_with(arg, "--relative=")) {
 		DIFF_OPT_SET(options, RELATIVE_NAME);
 		options->prefix = arg + 11;
 	}
@@ -3727,7 +3727,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, FOLLOW_RENAMES);
 	else if (!strcmp(arg, "--color"))
 		options->use_color = 1;
-	else if (!prefixcmp(arg, "--color=")) {
+	else if (starts_with(arg, "--color=")) {
 		int value = git_config_colorbool(NULL, arg+8);
 		if (value < 0)
 			return error("option `color' expects \"always\", \"auto\", or \"never\"");
@@ -3739,7 +3739,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->use_color = 1;
 		options->word_diff = DIFF_WORDS_COLOR;
 	}
-	else if (!prefixcmp(arg, "--color-words=")) {
+	else if (starts_with(arg, "--color-words=")) {
 		options->use_color = 1;
 		options->word_diff = DIFF_WORDS_COLOR;
 		options->word_regex = arg + 14;
@@ -3748,7 +3748,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		if (options->word_diff == DIFF_WORDS_NONE)
 			options->word_diff = DIFF_WORDS_PLAIN;
 	}
-	else if (!prefixcmp(arg, "--word-diff=")) {
+	else if (starts_with(arg, "--word-diff=")) {
 		const char *type = arg + 12;
 		if (!strcmp(type, "plain"))
 			options->word_diff = DIFF_WORDS_PLAIN;
@@ -3784,12 +3784,12 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 	else if (!strcmp(arg, "--ignore-submodules")) {
 		DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
 		handle_ignore_submodules_arg(options, "all");
-	} else if (!prefixcmp(arg, "--ignore-submodules=")) {
+	} else if (starts_with(arg, "--ignore-submodules=")) {
 		DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
 		handle_ignore_submodules_arg(options, arg + 20);
 	} else if (!strcmp(arg, "--submodule"))
 		DIFF_OPT_SET(options, SUBMODULE_LOG);
-	else if (!prefixcmp(arg, "--submodule="))
+	else if (starts_with(arg, "--submodule="))
 		return parse_submodule_opt(options, arg + 12);
 
 	/* misc options */
@@ -3825,7 +3825,7 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 	}
 	else if (!strcmp(arg, "--abbrev"))
 		options->abbrev = DEFAULT_ABBREV;
-	else if (!prefixcmp(arg, "--abbrev=")) {
+	else if (starts_with(arg, "--abbrev=")) {
 		options->abbrev = strtoul(arg + 9, NULL, 10);
 		if (options->abbrev < MINIMUM_ABBREV)
 			options->abbrev = MINIMUM_ABBREV;
@@ -3907,15 +3907,15 @@ static int diff_scoreopt_parse(const char *opt)
 	cmd = *opt++;
 	if (cmd == '-') {
 		/* convert the long-form arguments into short-form versions */
-		if (!prefixcmp(opt, "break-rewrites")) {
+		if (starts_with(opt, "break-rewrites")) {
 			opt += strlen("break-rewrites");
 			if (*opt == 0 || *opt++ == '=')
 				cmd = 'B';
-		} else if (!prefixcmp(opt, "find-copies")) {
+		} else if (starts_with(opt, "find-copies")) {
 			opt += strlen("find-copies");
 			if (*opt == 0 || *opt++ == '=')
 				cmd = 'C';
-		} else if (!prefixcmp(opt, "find-renames")) {
+		} else if (starts_with(opt, "find-renames")) {
 			opt += strlen("find-renames");
 			if (*opt == 0 || *opt++ == '=')
 				cmd = 'M';
@@ -4325,7 +4325,7 @@ static void patch_id_consume(void *priv, char *line, unsigned long len)
 	int new_len;
 
 	/* Ignore line numbers when computing the SHA1 of the patch */
-	if (!prefixcmp(line, "@@ -"))
+	if (starts_with(line, "@@ -"))
 		return;
 
 	new_len = remove_space(line, len);
diff --git a/environment.c b/environment.c
index cd2b068..3c76905 100644
--- a/environment.c
+++ b/environment.c
@@ -171,7 +171,7 @@ const char *get_git_namespace(void)
 
 const char *strip_namespace(const char *namespaced_ref)
 {
-	if (prefixcmp(namespaced_ref, get_git_namespace()))
+	if (!starts_with(namespaced_ref, get_git_namespace()))
 		return NULL;
 	return namespaced_ref + namespace_len;
 }
diff --git a/fast-import.c b/fast-import.c
index f4d9969..4fd18a3 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -1877,8 +1877,8 @@ static int read_next_command(void)
 				return EOF;
 
 			if (!seen_data_command
-				&& prefixcmp(command_buf.buf, "feature ")
-				&& prefixcmp(command_buf.buf, "option ")) {
+				&& !starts_with(command_buf.buf, "feature ")
+				&& !starts_with(command_buf.buf, "option ")) {
 				parse_argv();
 			}
 
@@ -1898,7 +1898,7 @@ static int read_next_command(void)
 			rc->prev->next = rc;
 			cmd_tail = rc;
 		}
-		if (!prefixcmp(command_buf.buf, "cat-blob ")) {
+		if (starts_with(command_buf.buf, "cat-blob ")) {
 			parse_cat_blob();
 			continue;
 		}
@@ -1917,7 +1917,7 @@ static void skip_optional_lf(void)
 
 static void parse_mark(void)
 {
-	if (!prefixcmp(command_buf.buf, "mark :")) {
+	if (starts_with(command_buf.buf, "mark :")) {
 		next_mark = strtoumax(command_buf.buf + 6, NULL, 10);
 		read_next_command();
 	}
@@ -1929,10 +1929,10 @@ static int parse_data(struct strbuf *sb, uintmax_t limit, uintmax_t *len_res)
 {
 	strbuf_reset(sb);
 
-	if (prefixcmp(command_buf.buf, "data "))
+	if (!starts_with(command_buf.buf, "data "))
 		die("Expected 'data n' command, found: %s", command_buf.buf);
 
-	if (!prefixcmp(command_buf.buf + 5, "<<")) {
+	if (starts_with(command_buf.buf + 5, "<<")) {
 		char *term = xstrdup(command_buf.buf + 5 + 2);
 		size_t term_len = command_buf.len - 5 - 2;
 
@@ -2306,7 +2306,7 @@ static void file_change_m(struct branch *b)
 	if (*p == ':') {
 		oe = find_mark(parse_mark_ref_space(&p));
 		hashcpy(sha1, oe->idx.sha1);
-	} else if (!prefixcmp(p, "inline ")) {
+	} else if (starts_with(p, "inline ")) {
 		inline_data = 1;
 		oe = NULL; /* not used with inline_data, but makes gcc happy */
 		p += strlen("inline");  /* advance to space */
@@ -2479,7 +2479,7 @@ static void note_change_n(struct branch *b, unsigned char *old_fanout)
 	if (*p == ':') {
 		oe = find_mark(parse_mark_ref_space(&p));
 		hashcpy(sha1, oe->idx.sha1);
-	} else if (!prefixcmp(p, "inline ")) {
+	} else if (starts_with(p, "inline ")) {
 		inline_data = 1;
 		oe = NULL; /* not used with inline_data, but makes gcc happy */
 		p += strlen("inline");  /* advance to space */
@@ -2590,7 +2590,7 @@ static int parse_from(struct branch *b)
 	const char *from;
 	struct branch *s;
 
-	if (prefixcmp(command_buf.buf, "from "))
+	if (!starts_with(command_buf.buf, "from "))
 		return 0;
 
 	if (b->branch_tree.tree) {
@@ -2636,7 +2636,7 @@ static struct hash_list *parse_merge(unsigned int *count)
 	struct branch *s;
 
 	*count = 0;
-	while (!prefixcmp(command_buf.buf, "merge ")) {
+	while (starts_with(command_buf.buf, "merge ")) {
 		from = strchr(command_buf.buf, ' ') + 1;
 		n = xmalloc(sizeof(*n));
 		s = lookup_branch(from);
@@ -2687,11 +2687,11 @@ static void parse_new_commit(void)
 
 	read_next_command();
 	parse_mark();
-	if (!prefixcmp(command_buf.buf, "author ")) {
+	if (starts_with(command_buf.buf, "author ")) {
 		author = parse_ident(command_buf.buf + 7);
 		read_next_command();
 	}
-	if (!prefixcmp(command_buf.buf, "committer ")) {
+	if (starts_with(command_buf.buf, "committer ")) {
 		committer = parse_ident(command_buf.buf + 10);
 		read_next_command();
 	}
@@ -2712,19 +2712,19 @@ static void parse_new_commit(void)
 
 	/* file_change* */
 	while (command_buf.len > 0) {
-		if (!prefixcmp(command_buf.buf, "M "))
+		if (starts_with(command_buf.buf, "M "))
 			file_change_m(b);
-		else if (!prefixcmp(command_buf.buf, "D "))
+		else if (starts_with(command_buf.buf, "D "))
 			file_change_d(b);
-		else if (!prefixcmp(command_buf.buf, "R "))
+		else if (starts_with(command_buf.buf, "R "))
 			file_change_cr(b, 1);
-		else if (!prefixcmp(command_buf.buf, "C "))
+		else if (starts_with(command_buf.buf, "C "))
 			file_change_cr(b, 0);
-		else if (!prefixcmp(command_buf.buf, "N "))
+		else if (starts_with(command_buf.buf, "N "))
 			note_change_n(b, &prev_fanout);
 		else if (!strcmp("deleteall", command_buf.buf))
 			file_change_deleteall(b);
-		else if (!prefixcmp(command_buf.buf, "ls "))
+		else if (starts_with(command_buf.buf, "ls "))
 			parse_ls(b);
 		else {
 			unread_command_buf = 1;
@@ -2793,7 +2793,7 @@ static void parse_new_tag(void)
 	read_next_command();
 
 	/* from ... */
-	if (prefixcmp(command_buf.buf, "from "))
+	if (!starts_with(command_buf.buf, "from "))
 		die("Expected from command, got %s", command_buf.buf);
 	from = strchr(command_buf.buf, ' ') + 1;
 	s = lookup_branch(from);
@@ -2821,7 +2821,7 @@ static void parse_new_tag(void)
 	read_next_command();
 
 	/* tagger ... */
-	if (!prefixcmp(command_buf.buf, "tagger ")) {
+	if (starts_with(command_buf.buf, "tagger ")) {
 		tagger = parse_ident(command_buf.buf + 7);
 		read_next_command();
 	} else
@@ -3209,7 +3209,7 @@ static void option_export_pack_edges(const char *edges)
 
 static int parse_one_option(const char *option)
 {
-	if (!prefixcmp(option, "max-pack-size=")) {
+	if (starts_with(option, "max-pack-size=")) {
 		unsigned long v;
 		if (!git_parse_ulong(option + 14, &v))
 			return 0;
@@ -3221,20 +3221,20 @@ static int parse_one_option(const char *option)
 			v = 1024 * 1024;
 		}
 		max_packsize = v;
-	} else if (!prefixcmp(option, "big-file-threshold=")) {
+	} else if (starts_with(option, "big-file-threshold=")) {
 		unsigned long v;
 		if (!git_parse_ulong(option + 19, &v))
 			return 0;
 		big_file_threshold = v;
-	} else if (!prefixcmp(option, "depth=")) {
+	} else if (starts_with(option, "depth=")) {
 		option_depth(option + 6);
-	} else if (!prefixcmp(option, "active-branches=")) {
+	} else if (starts_with(option, "active-branches=")) {
 		option_active_branches(option + 16);
-	} else if (!prefixcmp(option, "export-pack-edges=")) {
+	} else if (starts_with(option, "export-pack-edges=")) {
 		option_export_pack_edges(option + 18);
-	} else if (!prefixcmp(option, "quiet")) {
+	} else if (starts_with(option, "quiet")) {
 		show_stats = 0;
-	} else if (!prefixcmp(option, "stats")) {
+	} else if (starts_with(option, "stats")) {
 		show_stats = 1;
 	} else {
 		return 0;
@@ -3245,14 +3245,14 @@ static int parse_one_option(const char *option)
 
 static int parse_one_feature(const char *feature, int from_stream)
 {
-	if (!prefixcmp(feature, "date-format=")) {
+	if (starts_with(feature, "date-format=")) {
 		option_date_format(feature + 12);
-	} else if (!prefixcmp(feature, "import-marks=")) {
+	} else if (starts_with(feature, "import-marks=")) {
 		option_import_marks(feature + 13, from_stream, 0);
-	} else if (!prefixcmp(feature, "import-marks-if-exists=")) {
+	} else if (starts_with(feature, "import-marks-if-exists=")) {
 		option_import_marks(feature + strlen("import-marks-if-exists="),
 					from_stream, 1);
-	} else if (!prefixcmp(feature, "export-marks=")) {
+	} else if (starts_with(feature, "export-marks=")) {
 		option_export_marks(feature + 13);
 	} else if (!strcmp(feature, "cat-blob")) {
 		; /* Don't die - this feature is supported */
@@ -3350,7 +3350,7 @@ static void parse_argv(void)
 		if (parse_one_feature(a + 2, 0))
 			continue;
 
-		if (!prefixcmp(a + 2, "cat-blob-fd=")) {
+		if (starts_with(a + 2, "cat-blob-fd=")) {
 			option_cat_blob_fd(a + 2 + strlen("cat-blob-fd="));
 			continue;
 		}
@@ -3404,25 +3404,25 @@ int main(int argc, char **argv)
 	while (read_next_command() != EOF) {
 		if (!strcmp("blob", command_buf.buf))
 			parse_new_blob();
-		else if (!prefixcmp(command_buf.buf, "ls "))
+		else if (starts_with(command_buf.buf, "ls "))
 			parse_ls(NULL);
-		else if (!prefixcmp(command_buf.buf, "commit "))
+		else if (starts_with(command_buf.buf, "commit "))
 			parse_new_commit();
-		else if (!prefixcmp(command_buf.buf, "tag "))
+		else if (starts_with(command_buf.buf, "tag "))
 			parse_new_tag();
-		else if (!prefixcmp(command_buf.buf, "reset "))
+		else if (starts_with(command_buf.buf, "reset "))
 			parse_reset_branch();
 		else if (!strcmp("checkpoint", command_buf.buf))
 			parse_checkpoint();
 		else if (!strcmp("done", command_buf.buf))
 			break;
-		else if (!prefixcmp(command_buf.buf, "progress "))
+		else if (starts_with(command_buf.buf, "progress "))
 			parse_progress();
-		else if (!prefixcmp(command_buf.buf, "feature "))
+		else if (starts_with(command_buf.buf, "feature "))
 			parse_feature();
-		else if (!prefixcmp(command_buf.buf, "option git "))
+		else if (starts_with(command_buf.buf, "option git "))
 			parse_option();
-		else if (!prefixcmp(command_buf.buf, "option "))
+		else if (starts_with(command_buf.buf, "option "))
 			/* ignore non-git options*/;
 		else
 			die("Unsupported command: %s", command_buf.buf);
diff --git a/fetch-pack.c b/fetch-pack.c
index 1042448..36be5b2 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -176,9 +176,9 @@ static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 		 */
 		char *line;
 		while ((line = packet_read_line(fd, NULL))) {
-			if (!prefixcmp(line, "shallow "))
+			if (starts_with(line, "shallow "))
 				continue;
-			if (!prefixcmp(line, "unshallow "))
+			if (starts_with(line, "unshallow "))
 				continue;
 			die("git fetch-pack: expected shallow list");
 		}
@@ -194,7 +194,7 @@ static enum ack_type get_ack(int fd, unsigned char *result_sha1)
 		die("git fetch-pack: expected ACK/NAK, got EOF");
 	if (!strcmp(line, "NAK"))
 		return NAK;
-	if (!prefixcmp(line, "ACK ")) {
+	if (starts_with(line, "ACK ")) {
 		if (!get_sha1_hex(line+4, result_sha1)) {
 			if (len < 45)
 				return ACK;
@@ -323,13 +323,13 @@ static int find_common(struct fetch_pack_args *args,
 
 		send_request(args, fd[1], &req_buf);
 		while ((line = packet_read_line(fd[0], NULL))) {
-			if (!prefixcmp(line, "shallow ")) {
+			if (starts_with(line, "shallow ")) {
 				if (get_sha1_hex(line + 8, sha1))
 					die("invalid shallow line: %s", line);
 				register_shallow(sha1);
 				continue;
 			}
-			if (!prefixcmp(line, "unshallow ")) {
+			if (starts_with(line, "unshallow ")) {
 				if (get_sha1_hex(line + 10, sha1))
 					die("invalid unshallow line: %s", line);
 				if (!lookup_object(sha1))
@@ -523,7 +523,7 @@ static void filter_refs(struct fetch_pack_args *args,
 		}
 
 		if (!keep && args->fetch_all &&
-		    (!args->depth || prefixcmp(ref->name, "refs/tags/")))
+		    (!args->depth || !starts_with(ref->name, "refs/tags/")))
 			keep = 1;
 
 		if (keep) {
diff --git a/git.c b/git.c
index 727e380..3799514 100644
--- a/git.c
+++ b/git.c
@@ -54,7 +54,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 		/*
 		 * Check remaining flags.
 		 */
-		if (!prefixcmp(cmd, "--exec-path")) {
+		if (starts_with(cmd, "--exec-path")) {
 			cmd += 11;
 			if (*cmd == '=')
 				git_set_argv_exec_path(cmd + 1);
@@ -92,7 +92,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 				*envchanged = 1;
 			(*argv)++;
 			(*argc)--;
-		} else if (!prefixcmp(cmd, "--git-dir=")) {
+		} else if (starts_with(cmd, "--git-dir=")) {
 			setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
 			if (envchanged)
 				*envchanged = 1;
@@ -106,7 +106,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 				*envchanged = 1;
 			(*argv)++;
 			(*argc)--;
-		} else if (!prefixcmp(cmd, "--namespace=")) {
+		} else if (starts_with(cmd, "--namespace=")) {
 			setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
 			if (envchanged)
 				*envchanged = 1;
@@ -120,7 +120,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 				*envchanged = 1;
 			(*argv)++;
 			(*argc)--;
-		} else if (!prefixcmp(cmd, "--work-tree=")) {
+		} else if (starts_with(cmd, "--work-tree=")) {
 			setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 			if (envchanged)
 				*envchanged = 1;
@@ -566,7 +566,7 @@ int main(int argc, char **av)
 	 * So we just directly call the internal command handler, and
 	 * die if that one cannot handle it.
 	 */
-	if (!prefixcmp(cmd, "git-")) {
+	if (starts_with(cmd, "git-")) {
 		cmd += 4;
 		argv[0] = cmd;
 		handle_internal_command(argc, argv);
@@ -578,7 +578,7 @@ int main(int argc, char **av)
 	argc--;
 	handle_options(&argv, &argc, NULL);
 	if (argc > 0) {
-		if (!prefixcmp(argv[0], "--"))
+		if (starts_with(argv[0], "--"))
 			argv[0] += 2;
 	} else {
 		/* The user didn't specify a command; give them help */
diff --git a/help.c b/help.c
index f068925..df7d16d 100644
--- a/help.c
+++ b/help.c
@@ -148,7 +148,7 @@ static void list_commands_in_dir(struct cmdnames *cmds,
 	while ((de = readdir(dir)) != NULL) {
 		int entlen;
 
-		if (prefixcmp(de->d_name, prefix))
+		if (!starts_with(de->d_name, prefix))
 			continue;
 
 		strbuf_setlen(&buf, len);
@@ -255,7 +255,7 @@ static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 	if (!strcmp(var, "help.autocorrect"))
 		autocorrect = git_config_int(var,value);
 	/* Also use aliases for command lookup */
-	if (!prefixcmp(var, "alias."))
+	if (starts_with(var, "alias."))
 		add_cmdname(&aliases, var + 6, strlen(var + 6));
 
 	return git_default_config(var, value, cb);
@@ -329,7 +329,7 @@ const char *help_unknown_cmd(const char *cmd)
 		if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
 			/* Yes, this is one of the common commands */
 			n++; /* use the entry from common_cmds[] */
-			if (!prefixcmp(candidate, cmd)) {
+			if (starts_with(candidate, cmd)) {
 				/* Give prefix match a very good score */
 				main_cmds.names[i]->len = 0;
 				continue;
@@ -414,7 +414,7 @@ static int append_similar_ref(const char *refname, const unsigned char *sha1,
 	struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 	char *branch = strrchr(refname, '/') + 1;
 	/* A remote branch of the same name is deemed similar */
-	if (!prefixcmp(refname, "refs/remotes/") &&
+	if (starts_with(refname, "refs/remotes/") &&
 	    !strcmp(branch, cb->base_ref))
 		string_list_append(cb->similar_refs,
 				   refname + strlen("refs/remotes/"));
diff --git a/http-backend.c b/http-backend.c
index 8c464bd..d2c0a62 100644
--- a/http-backend.c
+++ b/http-backend.c
@@ -226,7 +226,7 @@ static int http_config(const char *var, const char *value, void *cb)
 		return 0;
 	}
 
-	if (!prefixcmp(var, "http.")) {
+	if (starts_with(var, "http.")) {
 		int i;
 
 		for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
@@ -247,7 +247,7 @@ static struct rpc_service *select_service(const char *name)
 	struct rpc_service *svc = NULL;
 	int i;
 
-	if (prefixcmp(name, "git-"))
+	if (!starts_with(name, "git-"))
 		forbidden("Unsupported service: '%s'", name);
 
 	for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
diff --git a/http-push.c b/http-push.c
index 34cb70f..d4b40c9 100644
--- a/http-push.c
+++ b/http-push.c
@@ -771,7 +771,7 @@ static void handle_new_lock_ctx(struct xml_ctx *ctx, int tag_closed)
 			lock->owner = xmalloc(strlen(ctx->cdata) + 1);
 			strcpy(lock->owner, ctx->cdata);
 		} else if (!strcmp(ctx->name, DAV_ACTIVELOCK_TIMEOUT)) {
-			if (!prefixcmp(ctx->cdata, "Second-"))
+			if (starts_with(ctx->cdata, "Second-"))
 				lock->timeout =
 					strtol(ctx->cdata + 7, NULL, 10);
 		} else if (!strcmp(ctx->name, DAV_ACTIVELOCK_TOKEN)) {
@@ -1579,7 +1579,7 @@ static void fetch_symref(const char *path, char **symref, unsigned char *sha1)
 		return;
 
 	/* If it's a symref, set the refname; otherwise try for a sha1 */
-	if (!prefixcmp((char *)buffer.buf, "ref: ")) {
+	if (starts_with((char *)buffer.buf, "ref: ")) {
 		*symref = xmemdupz((char *)buffer.buf + 5, buffer.len - 6);
 	} else {
 		get_sha1_hex(buffer.buf, sha1);
diff --git a/http.c b/http.c
index bcf54aa..e6287b1 100644
--- a/http.c
+++ b/http.c
@@ -460,7 +460,7 @@ void http_init(struct remote *remote, const char *url, int proactive_auth)
 		credential_from_url(&http_auth, url);
 		if (!ssl_cert_password_required &&
 		    getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
-		    !prefixcmp(url, "https://"))
+		    starts_with(url, "https://"))
 			ssl_cert_password_required = 1;
 	}
 
@@ -994,7 +994,7 @@ static int update_url_from_redirect(struct strbuf *base,
 	if (!strcmp(asked, got->buf))
 		return 0;
 
-	if (prefixcmp(asked, base->buf))
+	if (!starts_with(asked, base->buf))
 		die("BUG: update_url_from_redirect: %s is not a superset of %s",
 		    asked, base->buf);
 
@@ -1100,7 +1100,7 @@ int http_fetch_ref(const char *base, struct ref *ref)
 		strbuf_rtrim(&buffer);
 		if (buffer.len == 40)
 			ret = get_sha1_hex(buffer.buf, ref->old_sha1);
-		else if (!prefixcmp(buffer.buf, "ref: ")) {
+		else if (starts_with(buffer.buf, "ref: ")) {
 			ref->symref = xstrdup(buffer.buf + 5);
 			ret = 0;
 		}
@@ -1201,8 +1201,8 @@ int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
 		case 'P':
 			i++;
 			if (i + 52 <= buf.len &&
-			    !prefixcmp(data + i, " pack-") &&
-			    !prefixcmp(data + i + 46, ".pack\n")) {
+			    starts_with(data + i, " pack-") &&
+			    starts_with(data + i + 46, ".pack\n")) {
 				get_sha1_hex(data + i + 6, sha1);
 				fetch_and_setup_pack_index(packs_head, sha1,
 						      base_url);
diff --git a/imap-send.c b/imap-send.c
index 6f5cc4f..0bc6f7f 100644
--- a/imap-send.c
+++ b/imap-send.c
@@ -1263,7 +1263,7 @@ static int count_messages(struct strbuf *all_msgs)
 	char *p = all_msgs->buf;
 
 	while (1) {
-		if (!prefixcmp(p, "From ")) {
+		if (starts_with(p, "From ")) {
 			p = strstr(p+5, "\nFrom: ");
 			if (!p) break;
 			p = strstr(p+7, "\nDate: ");
@@ -1297,7 +1297,7 @@ static int split_msg(struct strbuf *all_msgs, struct strbuf *msg, int *ofs)
 	data = &all_msgs->buf[*ofs];
 	len = all_msgs->len - *ofs;
 
-	if (len < 5 || prefixcmp(data, "From "))
+	if (len < 5 || !starts_with(data, "From "))
 		return 0;
 
 	p = strchr(data, '\n');
@@ -1339,13 +1339,13 @@ static int git_imap_config(const char *key, const char *val, void *cb)
 	if (!strcmp("folder", key)) {
 		imap_folder = xstrdup(val);
 	} else if (!strcmp("host", key)) {
-		if (!prefixcmp(val, "imap:"))
+		if (starts_with(val, "imap:"))
 			val += 5;
-		else if (!prefixcmp(val, "imaps:")) {
+		else if (starts_with(val, "imaps:")) {
 			val += 6;
 			server.use_ssl = 1;
 		}
-		if (!prefixcmp(val, "//"))
+		if (starts_with(val, "//"))
 			val += 2;
 		server.host = xstrdup(val);
 	} else if (!strcmp("user", key))
diff --git a/log-tree.c b/log-tree.c
index 8534d91..40ef3ea 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -98,7 +98,7 @@ static int add_ref_decoration(const char *refname, const unsigned char *sha1, in
 	struct object *obj;
 	enum decoration_type type = DECORATION_NONE;
 
-	if (!prefixcmp(refname, "refs/replace/")) {
+	if (starts_with(refname, "refs/replace/")) {
 		unsigned char original_sha1[20];
 		if (!read_replace_refs)
 			return 0;
@@ -116,11 +116,11 @@ static int add_ref_decoration(const char *refname, const unsigned char *sha1, in
 	if (!obj)
 		return 0;
 
-	if (!prefixcmp(refname, "refs/heads/"))
+	if (starts_with(refname, "refs/heads/"))
 		type = DECORATION_REF_LOCAL;
-	else if (!prefixcmp(refname, "refs/remotes/"))
+	else if (starts_with(refname, "refs/remotes/"))
 		type = DECORATION_REF_REMOTE;
-	else if (!prefixcmp(refname, "refs/tags/"))
+	else if (starts_with(refname, "refs/tags/"))
 		type = DECORATION_REF_TAG;
 	else if (!strcmp(refname, "refs/stash"))
 		type = DECORATION_REF_STASH;
diff --git a/merge-recursive.c b/merge-recursive.c
index dbb7104..a18bd15 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -2063,13 +2063,13 @@ int parse_merge_opt(struct merge_options *o, const char *s)
 		o->recursive_variant = MERGE_RECURSIVE_THEIRS;
 	else if (!strcmp(s, "subtree"))
 		o->subtree_shift = "";
-	else if (!prefixcmp(s, "subtree="))
+	else if (starts_with(s, "subtree="))
 		o->subtree_shift = s + strlen("subtree=");
 	else if (!strcmp(s, "patience"))
 		o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF);
 	else if (!strcmp(s, "histogram"))
 		o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF);
-	else if (!prefixcmp(s, "diff-algorithm=")) {
+	else if (starts_with(s, "diff-algorithm=")) {
 		long value = parse_algorithm_value(s + strlen("diff-algorithm="));
 		if (value < 0)
 			return -1;
@@ -2088,7 +2088,7 @@ int parse_merge_opt(struct merge_options *o, const char *s)
 		o->renormalize = 1;
 	else if (!strcmp(s, "no-renormalize"))
 		o->renormalize = 0;
-	else if (!prefixcmp(s, "rename-threshold=")) {
+	else if (starts_with(s, "rename-threshold=")) {
 		const char *score = s + strlen("rename-threshold=");
 		if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0)
 			return -1;
diff --git a/notes-utils.c b/notes-utils.c
index 9107c37..db43900 100644
--- a/notes-utils.c
+++ b/notes-utils.c
@@ -70,7 +70,7 @@ static combine_notes_fn parse_combine_notes_fn(const char *v)
 static int notes_rewrite_config(const char *k, const char *v, void *cb)
 {
 	struct notes_rewrite_cfg *c = cb;
-	if (!prefixcmp(k, "notes.rewrite.") && !strcmp(k+14, c->cmd)) {
+	if (starts_with(k, "notes.rewrite.") && !strcmp(k+14, c->cmd)) {
 		c->enabled = git_config_bool(k, v);
 		return 0;
 	} else if (!c->mode_from_env && !strcmp(k, "notes.rewritemode")) {
@@ -85,7 +85,7 @@ static int notes_rewrite_config(const char *k, const char *v, void *cb)
 	} else if (!c->refs_from_env && !strcmp(k, "notes.rewriteref")) {
 		/* note that a refs/ prefix is implied in the
 		 * underlying for_each_glob_ref */
-		if (!prefixcmp(v, "refs/notes/"))
+		if (starts_with(v, "refs/notes/"))
 			string_list_add_refs_by_glob(c->refs, v);
 		else
 			warning(_("Refusing to rewrite notes in %s"
diff --git a/notes.c b/notes.c
index b69c0b8..5f07c0b 100644
--- a/notes.c
+++ b/notes.c
@@ -1243,9 +1243,9 @@ static void format_note(struct notes_tree *t, const unsigned char *object_sha1,
 		if (!ref || !strcmp(ref, GIT_NOTES_DEFAULT_REF)) {
 			strbuf_addstr(sb, "\nNotes:\n");
 		} else {
-			if (!prefixcmp(ref, "refs/"))
+			if (starts_with(ref, "refs/"))
 				ref += 5;
-			if (!prefixcmp(ref, "notes/"))
+			if (starts_with(ref, "notes/"))
 				ref += 6;
 			strbuf_addf(sb, "\nNotes (%s):\n", ref);
 		}
@@ -1293,9 +1293,9 @@ int copy_note(struct notes_tree *t,
 
 void expand_notes_ref(struct strbuf *sb)
 {
-	if (!prefixcmp(sb->buf, "refs/notes/"))
+	if (starts_with(sb->buf, "refs/notes/"))
 		return; /* we're happy */
-	else if (!prefixcmp(sb->buf, "notes/"))
+	else if (starts_with(sb->buf, "notes/"))
 		strbuf_insert(sb, 0, "refs/", 5);
 	else
 		strbuf_insert(sb, 0, "refs/notes/", 11);
diff --git a/pager.c b/pager.c
index fa19765..345b0bc 100644
--- a/pager.c
+++ b/pager.c
@@ -151,7 +151,7 @@ int decimal_width(int number)
 static int pager_command_config(const char *var, const char *value, void *data)
 {
 	struct pager_config *c = data;
-	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd)) {
+	if (starts_with(var, "pager.") && !strcmp(var + 6, c->cmd)) {
 		int b = git_config_maybe_bool(var, value);
 		if (b >= 0)
 			c->want = b;
diff --git a/parse-options.c b/parse-options.c
index 62e9b1c..7b8d3fa 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -273,13 +273,13 @@ is_abbreviated:
 			if (options->flags & PARSE_OPT_NONEG)
 				continue;
 			/* negated and abbreviated very much? */
-			if (!prefixcmp("no-", arg)) {
+			if (starts_with("no-", arg)) {
 				flags |= OPT_UNSET;
 				goto is_abbreviated;
 			}
 			/* negated? */
-			if (prefixcmp(arg, "no-")) {
-				if (!prefixcmp(long_name, "no-")) {
+			if (!starts_with(arg, "no-")) {
+				if (starts_with(long_name, "no-")) {
 					long_name += 3;
 					opt_flags |= OPT_UNSET;
 					goto again;
@@ -289,7 +289,7 @@ is_abbreviated:
 			flags |= OPT_UNSET;
 			rest = skip_prefix(arg + 3, long_name);
 			/* abbreviated and negated? */
-			if (!rest && !prefixcmp(long_name, arg + 3))
+			if (!rest && starts_with(long_name, arg + 3))
 				goto is_abbreviated;
 			if (!rest)
 				continue;
@@ -334,7 +334,7 @@ static void check_typos(const char *arg, const struct option *options)
 	if (strlen(arg) < 3)
 		return;
 
-	if (!prefixcmp(arg, "no-")) {
+	if (starts_with(arg, "no-")) {
 		error ("did you mean `--%s` (with two dashes ?)", arg);
 		exit(129);
 	}
@@ -342,7 +342,7 @@ static void check_typos(const char *arg, const struct option *options)
 	for (; options->type != OPTION_END; options++) {
 		if (!options->long_name)
 			continue;
-		if (!prefixcmp(options->long_name, arg)) {
+		if (starts_with(options->long_name, arg)) {
 			error ("did you mean `--%s` (with two dashes ?)", arg);
 			exit(129);
 		}
diff --git a/pathspec.c b/pathspec.c
index 4cf2bd3..4a7893e 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -154,7 +154,7 @@ static unsigned prefix_pathspec(struct pathspec_item *item,
 					magic |= pathspec_magic[i].bit;
 					break;
 				}
-				if (!prefixcmp(copyfrom, "prefix:")) {
+				if (starts_with(copyfrom, "prefix:")) {
 					char *endptr;
 					pathspec_prefix = strtol(copyfrom + 7,
 								 &endptr, 10);
diff --git a/pkt-line.c b/pkt-line.c
index 70f1950..bc63b3b 100644
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -24,8 +24,8 @@ static void packet_trace(const char *buf, unsigned int len, int write)
 	strbuf_addf(&out, "packet: %12s%c ",
 		    packet_trace_prefix, write ? '>' : '<');
 
-	if ((len >= 4 && !prefixcmp(buf, "PACK")) ||
-	    (len >= 5 && !prefixcmp(buf+1, "PACK"))) {
+	if ((len >= 4 && starts_with(buf, "PACK")) ||
+	    (len >= 5 && starts_with(buf+1, "PACK"))) {
 		strbuf_addstr(&out, "PACK ...");
 		unsetenv(trace_key);
 	}
diff --git a/pretty.c b/pretty.c
index 962e82b..87db08b 100644
--- a/pretty.c
+++ b/pretty.c
@@ -40,7 +40,7 @@ static int git_pretty_formats_config(const char *var, const char *value, void *c
 	const char *fmt;
 	int i;
 
-	if (prefixcmp(var, "pretty."))
+	if (!starts_with(var, "pretty."))
 		return 0;
 
 	name = var + strlen("pretty.");
@@ -67,7 +67,7 @@ static int git_pretty_formats_config(const char *var, const char *value, void *c
 	commit_format->name = xstrdup(name);
 	commit_format->format = CMIT_FMT_USERFORMAT;
 	git_config_string(&fmt, var, value);
-	if (!prefixcmp(fmt, "format:") || !prefixcmp(fmt, "tformat:")) {
+	if (starts_with(fmt, "format:") || starts_with(fmt, "tformat:")) {
 		commit_format->is_tformat = fmt[0] == 't';
 		fmt = strchr(fmt, ':') + 1;
 	} else if (strchr(fmt, '%'))
@@ -115,7 +115,7 @@ static struct cmt_fmt_map *find_commit_format_recursive(const char *sought,
 	for (i = 0; i < commit_formats_len; i++) {
 		size_t match_len;
 
-		if (prefixcmp(commit_formats[i].name, sought))
+		if (!starts_with(commit_formats[i].name, sought))
 			continue;
 
 		match_len = strlen(commit_formats[i].name);
@@ -151,7 +151,7 @@ void get_commit_format(const char *arg, struct rev_info *rev)
 		rev->commit_format = CMIT_FMT_DEFAULT;
 		return;
 	}
-	if (!prefixcmp(arg, "format:") || !prefixcmp(arg, "tformat:")) {
+	if (starts_with(arg, "format:") || starts_with(arg, "tformat:")) {
 		save_user_format(rev, strchr(arg, ':') + 1, arg[0] == 't');
 		return;
 	}
@@ -840,10 +840,10 @@ static void parse_commit_header(struct format_commit_context *context)
 
 		if (i == eol) {
 			break;
-		} else if (!prefixcmp(msg + i, "author ")) {
+		} else if (starts_with(msg + i, "author ")) {
 			context->author.off = i + 7;
 			context->author.len = eol - i - 7;
-		} else if (!prefixcmp(msg + i, "committer ")) {
+		} else if (starts_with(msg + i, "committer ")) {
 			context->committer.off = i + 10;
 			context->committer.len = eol - i - 10;
 		}
@@ -983,7 +983,7 @@ static size_t parse_color(struct strbuf *sb, /* in UTF-8 */
 
 		if (!end)
 			return 0;
-		if (!prefixcmp(begin, "auto,")) {
+		if (starts_with(begin, "auto,")) {
 			if (!want_color(c->pretty_ctx->color))
 				return end - placeholder + 1;
 			begin += 5;
@@ -994,16 +994,16 @@ static size_t parse_color(struct strbuf *sb, /* in UTF-8 */
 		strbuf_addstr(sb, color);
 		return end - placeholder + 1;
 	}
-	if (!prefixcmp(placeholder + 1, "red")) {
+	if (starts_with(placeholder + 1, "red")) {
 		strbuf_addstr(sb, GIT_COLOR_RED);
 		return 4;
-	} else if (!prefixcmp(placeholder + 1, "green")) {
+	} else if (starts_with(placeholder + 1, "green")) {
 		strbuf_addstr(sb, GIT_COLOR_GREEN);
 		return 6;
-	} else if (!prefixcmp(placeholder + 1, "blue")) {
+	} else if (starts_with(placeholder + 1, "blue")) {
 		strbuf_addstr(sb, GIT_COLOR_BLUE);
 		return 5;
-	} else if (!prefixcmp(placeholder + 1, "reset")) {
+	} else if (starts_with(placeholder + 1, "reset")) {
 		strbuf_addstr(sb, GIT_COLOR_RESET);
 		return 6;
 	} else
@@ -1060,11 +1060,11 @@ static size_t parse_padding_placeholder(struct strbuf *sb,
 			end = strchr(start, ')');
 			if (!end || end == start)
 				return 0;
-			if (!prefixcmp(start, "trunc)"))
+			if (starts_with(start, "trunc)"))
 				c->truncate = trunc_right;
-			else if (!prefixcmp(start, "ltrunc)"))
+			else if (starts_with(start, "ltrunc)"))
 				c->truncate = trunc_left;
-			else if (!prefixcmp(start, "mtrunc)"))
+			else if (starts_with(start, "mtrunc)"))
 				c->truncate = trunc_middle;
 			else
 				return 0;
@@ -1089,7 +1089,7 @@ static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
 	/* these are independent of the commit */
 	switch (placeholder[0]) {
 	case 'C':
-		if (!prefixcmp(placeholder + 1, "(auto)")) {
+		if (starts_with(placeholder + 1, "(auto)")) {
 			c->auto_color = 1;
 			return 7; /* consumed 7 bytes, "C(auto)" */
 		} else {
@@ -1556,7 +1556,7 @@ static void pp_header(struct pretty_print_context *pp,
 			continue;
 		}
 
-		if (!prefixcmp(line, "parent ")) {
+		if (starts_with(line, "parent ")) {
 			if (linelen != 48)
 				die("bad parent line in commit");
 			continue;
@@ -1580,11 +1580,11 @@ static void pp_header(struct pretty_print_context *pp,
 		 * FULL shows both authors but not dates.
 		 * FULLER shows both authors and dates.
 		 */
-		if (!prefixcmp(line, "author ")) {
+		if (starts_with(line, "author ")) {
 			strbuf_grow(sb, linelen + 80);
 			pp_user_info(pp, "Author", sb, line + 7, encoding);
 		}
-		if (!prefixcmp(line, "committer ") &&
+		if (starts_with(line, "committer ") &&
 		    (pp->fmt == CMIT_FMT_FULL || pp->fmt == CMIT_FMT_FULLER)) {
 			strbuf_grow(sb, linelen + 80);
 			pp_user_info(pp, "Commit", sb, line + 10, encoding);
diff --git a/refs.c b/refs.c
index 5e5a382..3926136 100644
--- a/refs.c
+++ b/refs.c
@@ -637,7 +637,7 @@ static int do_one_ref(struct ref_entry *entry, void *cb_data)
 	struct ref_entry *old_current_ref;
 	int retval;
 
-	if (prefixcmp(entry->name, data->base))
+	if (!starts_with(entry->name, data->base))
 		return 0;
 
 	if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
@@ -1042,7 +1042,7 @@ static void read_packed_refs(FILE *f, struct ref_dir *dir)
 		if (refname) {
 			last = create_ref_entry(refname, sha1, REF_ISPACKED, 1);
 			if (peeled == PEELED_FULLY ||
-			    (peeled == PEELED_TAGS && !prefixcmp(refname, "refs/tags/")))
+			    (peeled == PEELED_TAGS && starts_with(refname, "refs/tags/")))
 				last->flag |= REF_KNOWS_PEELED;
 			add_ref(dir, last);
 			continue;
@@ -1376,7 +1376,7 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 					return NULL;
 			}
 			buffer[len] = 0;
-			if (!prefixcmp(buffer, "refs/") &&
+			if (starts_with(buffer, "refs/") &&
 					!check_refname_format(buffer, 0)) {
 				strcpy(refname_buffer, buffer);
 				refname = refname_buffer;
@@ -1415,7 +1415,7 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 		/*
 		 * Is it a symbolic ref?
 		 */
-		if (prefixcmp(buffer, "ref:")) {
+		if (!starts_with(buffer, "ref:")) {
 			/*
 			 * Please note that FETCH_HEAD has a second
 			 * line containing other data.
@@ -1837,7 +1837,7 @@ int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 	struct ref_filter filter;
 	int ret;
 
-	if (!prefix && prefixcmp(pattern, "refs/"))
+	if (!prefix && !starts_with(pattern, "refs/"))
 		strbuf_addstr(&real_pattern, "refs/");
 	else if (prefix)
 		strbuf_addstr(&real_pattern, prefix);
@@ -1874,9 +1874,9 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)
 const char *prettify_refname(const char *name)
 {
 	return name + (
-		!prefixcmp(name, "refs/heads/") ? 11 :
-		!prefixcmp(name, "refs/tags/") ? 10 :
-		!prefixcmp(name, "refs/remotes/") ? 13 :
+		starts_with(name, "refs/heads/") ? 11 :
+		starts_with(name, "refs/tags/") ? 10 :
+		starts_with(name, "refs/remotes/") ? 13 :
 		0);
 }
 
@@ -2244,7 +2244,7 @@ static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
 	struct pack_refs_cb_data *cb = cb_data;
 	enum peel_status peel_status;
 	struct ref_entry *packed_entry;
-	int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
+	int is_tag_ref = starts_with(entry->name, "refs/tags/");
 
 	/* ALWAYS pack tags */
 	if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
@@ -2679,9 +2679,9 @@ int log_ref_setup(const char *refname, char *logfile, int bufsize)
 
 	git_snpath(logfile, bufsize, "logs/%s", refname);
 	if (log_all_ref_updates &&
-	    (!prefixcmp(refname, "refs/heads/") ||
-	     !prefixcmp(refname, "refs/remotes/") ||
-	     !prefixcmp(refname, "refs/notes/") ||
+	    (starts_with(refname, "refs/heads/") ||
+	     starts_with(refname, "refs/remotes/") ||
+	     starts_with(refname, "refs/notes/") ||
 	     !strcmp(refname, "HEAD"))) {
 		if (safe_create_leading_directories(logfile) < 0)
 			return error("unable to create directory for %s",
@@ -2751,7 +2751,7 @@ static int log_ref_write(const char *refname, const unsigned char *old_sha1,
 
 static int is_branch(const char *refname)
 {
-	return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
+	return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
 }
 
 int write_ref_sha1(struct ref_lock *lock,
@@ -3450,7 +3450,7 @@ int parse_hide_refs_config(const char *var, const char *value, const char *secti
 {
 	if (!strcmp("transfer.hiderefs", var) ||
 	    /* NEEDSWORK: use parse_config_key() once both are merged */
-	    (!prefixcmp(var, section) && var[strlen(section)] == '.' &&
+	    (starts_with(var, section) && var[strlen(section)] == '.' &&
 	     !strcmp(var + strlen(section), ".hiderefs"))) {
 		char *ref;
 		int len;
@@ -3478,7 +3478,7 @@ int ref_is_hidden(const char *refname)
 		return 0;
 	for_each_string_list_item(item, hide_refs) {
 		int len;
-		if (prefixcmp(refname, item->string))
+		if (!starts_with(refname, item->string))
 			continue;
 		len = strlen(item->string);
 		if (!refname[len] || refname[len] == '/')
diff --git a/remote-curl.c b/remote-curl.c
index c9b891a..65c403d 100644
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -217,7 +217,7 @@ static struct discovery* discover_refs(const char *service, int for_push)
 	free_discovery(last);
 
 	strbuf_addf(&refs_url, "%sinfo/refs", url.buf);
-	if ((!prefixcmp(url.buf, "http://") || !prefixcmp(url.buf, "https://")) &&
+	if ((starts_with(url.buf, "http://") || starts_with(url.buf, "https://")) &&
 	     git_env_bool("GIT_SMART_HTTP", 1)) {
 		maybe_smart = 1;
 		if (!strchr(url.buf, '?'))
@@ -755,7 +755,7 @@ static void parse_fetch(struct strbuf *buf)
 	int alloc_heads = 0, nr_heads = 0;
 
 	do {
-		if (!prefixcmp(buf->buf, "fetch ")) {
+		if (starts_with(buf->buf, "fetch ")) {
 			char *p = buf->buf + strlen("fetch ");
 			char *name;
 			struct ref *ref;
@@ -878,7 +878,7 @@ static void parse_push(struct strbuf *buf)
 	int alloc_spec = 0, nr_spec = 0, i, ret;
 
 	do {
-		if (!prefixcmp(buf->buf, "push ")) {
+		if (starts_with(buf->buf, "push ")) {
 			ALLOC_GROW(specs, nr_spec + 1, alloc_spec);
 			specs[nr_spec++] = xstrdup(buf->buf + 5);
 		}
@@ -941,19 +941,19 @@ int main(int argc, const char **argv)
 		}
 		if (buf.len == 0)
 			break;
-		if (!prefixcmp(buf.buf, "fetch ")) {
+		if (starts_with(buf.buf, "fetch ")) {
 			if (nongit)
 				die("Fetch attempted without a local repo");
 			parse_fetch(&buf);
 
-		} else if (!strcmp(buf.buf, "list") || !prefixcmp(buf.buf, "list ")) {
+		} else if (!strcmp(buf.buf, "list") || starts_with(buf.buf, "list ")) {
 			int for_push = !!strstr(buf.buf + 4, "for-push");
 			output_refs(get_refs(for_push));
 
-		} else if (!prefixcmp(buf.buf, "push ")) {
+		} else if (starts_with(buf.buf, "push ")) {
 			parse_push(&buf);
 
-		} else if (!prefixcmp(buf.buf, "option ")) {
+		} else if (starts_with(buf.buf, "option ")) {
 			char *name = buf.buf + strlen("option ");
 			char *value = strchr(name, ' ');
 			int result;
diff --git a/remote-testsvn.c b/remote-testsvn.c
index d7cd5d2..078f1ff 100644
--- a/remote-testsvn.c
+++ b/remote-testsvn.c
@@ -82,7 +82,7 @@ static int parse_rev_note(const char *msg, struct rev_note *res)
 		len = end ? end - msg : strlen(msg);
 
 		key = "Revision-number: ";
-		if (!prefixcmp(msg, key)) {
+		if (starts_with(msg, key)) {
 			long i;
 			char *end;
 			value = msg + strlen(key);
@@ -154,7 +154,7 @@ static void check_or_regenerate_marks(int latestrev)
 	} else {
 		strbuf_addf(&sb, ":%d ", latestrev);
 		while (strbuf_getline(&line, marksfile, '\n') != EOF) {
-			if (!prefixcmp(line.buf, sb.buf)) {
+			if (starts_with(line.buf, sb.buf)) {
 				found++;
 				break;
 			}
@@ -264,7 +264,7 @@ static int do_command(struct strbuf *line)
 		return 1;	/* end of command stream, quit */
 	}
 	if (batch_cmd) {
-		if (prefixcmp(batch_cmd->name, line->buf))
+		if (!starts_with(batch_cmd->name, line->buf))
 			die("Active %s batch interrupted by %s", batch_cmd->name, line->buf);
 		/* buffer batch lines */
 		string_list_append(&batchlines, line->buf);
@@ -272,7 +272,7 @@ static int do_command(struct strbuf *line)
 	}
 
 	for (p = input_command_list; p->name; p++) {
-		if (!prefixcmp(line->buf, p->name) && (strlen(p->name) == line->len ||
+		if (starts_with(line->buf, p->name) && (strlen(p->name) == line->len ||
 				line->buf[strlen(p->name)] == ' ')) {
 			if (p->batchable) {
 				batch_cmd = p;
@@ -304,7 +304,7 @@ int main(int argc, char **argv)
 	remote = remote_get(argv[1]);
 	url_in = (argc == 3) ? argv[2] : remote->url[0];
 
-	if (!prefixcmp(url_in, "file://")) {
+	if (starts_with(url_in, "file://")) {
 		dump_from_file = 1;
 		url = url_decode(url_in + sizeof("file://")-1);
 	} else {
diff --git a/remote.c b/remote.c
index 9f1a8aa..01aa4b4 100644
--- a/remote.c
+++ b/remote.c
@@ -76,7 +76,7 @@ static const char *alias_url(const char *url, struct rewrites *r)
 		if (!r->rewrite[i])
 			continue;
 		for (j = 0; j < r->rewrite[i]->instead_of_nr; j++) {
-			if (!prefixcmp(url, r->rewrite[i]->instead_of[j].s) &&
+			if (starts_with(url, r->rewrite[i]->instead_of[j].s) &&
 			    (!longest ||
 			     longest->len < r->rewrite[i]->instead_of[j].len)) {
 				longest = &(r->rewrite[i]->instead_of[j]);
@@ -239,13 +239,13 @@ static void read_remotes_file(struct remote *remote)
 		int value_list;
 		char *s, *p;
 
-		if (!prefixcmp(buffer, "URL:")) {
+		if (starts_with(buffer, "URL:")) {
 			value_list = 0;
 			s = buffer + 4;
-		} else if (!prefixcmp(buffer, "Push:")) {
+		} else if (starts_with(buffer, "Push:")) {
 			value_list = 1;
 			s = buffer + 5;
-		} else if (!prefixcmp(buffer, "Pull:")) {
+		} else if (starts_with(buffer, "Pull:")) {
 			value_list = 2;
 			s = buffer + 5;
 		} else
@@ -337,7 +337,7 @@ static int handle_config(const char *key, const char *value, void *cb)
 	const char *subkey;
 	struct remote *remote;
 	struct branch *branch;
-	if (!prefixcmp(key, "branch.")) {
+	if (starts_with(key, "branch.")) {
 		name = key + 7;
 		subkey = strrchr(name, '.');
 		if (!subkey)
@@ -361,7 +361,7 @@ static int handle_config(const char *key, const char *value, void *cb)
 		}
 		return 0;
 	}
-	if (!prefixcmp(key, "url.")) {
+	if (starts_with(key, "url.")) {
 		struct rewrite *rewrite;
 		name = key + 4;
 		subkey = strrchr(name, '.');
@@ -380,7 +380,7 @@ static int handle_config(const char *key, const char *value, void *cb)
 		}
 	}
 
-	if (prefixcmp(key,  "remote."))
+	if (!starts_with(key,  "remote."))
 		return 0;
 	name = key + 7;
 
@@ -487,7 +487,7 @@ static void read_config(void)
 	current_branch = NULL;
 	head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 	if (head_ref && (flag & REF_ISSYMREF) &&
-	    !prefixcmp(head_ref, "refs/heads/")) {
+	    starts_with(head_ref, "refs/heads/")) {
 		current_branch =
 			make_branch(head_ref + strlen("refs/heads/"), 0);
 	}
@@ -982,8 +982,8 @@ static int count_refspec_match(const char *pattern,
 		 */
 		if (namelen != patlen &&
 		    patlen != namelen - 5 &&
-		    prefixcmp(name, "refs/heads/") &&
-		    prefixcmp(name, "refs/tags/")) {
+		    !starts_with(name, "refs/heads/") &&
+		    !starts_with(name, "refs/tags/")) {
 			/* We want to catch the case where only weak
 			 * matches are found and there are multiple
 			 * matches, and where more than one strong
@@ -1054,9 +1054,9 @@ static char *guess_ref(const char *name, struct ref *peer)
 	if (!r)
 		return NULL;
 
-	if (!prefixcmp(r, "refs/heads/"))
+	if (starts_with(r, "refs/heads/"))
 		strbuf_addstr(&buf, "refs/heads/");
-	else if (!prefixcmp(r, "refs/tags/"))
+	else if (starts_with(r, "refs/tags/"))
 		strbuf_addstr(&buf, "refs/tags/");
 	else
 		return NULL;
@@ -1104,7 +1104,7 @@ static int match_explicit(struct ref *src, struct ref *dst,
 		dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
 		if (!dst_value ||
 		    ((flag & REF_ISSYMREF) &&
-		     prefixcmp(dst_value, "refs/heads/")))
+		     !starts_with(dst_value, "refs/heads/")))
 			die("%s cannot be resolved to branch.",
 			    matched_src->name);
 	}
@@ -1193,7 +1193,7 @@ static char *get_ref_match(const struct refspec *rs, int rs_nr, const struct ref
 		 * including refs outside refs/heads/ hierarchy, but
 		 * that does not make much sense these days.
 		 */
-		if (!send_mirror && prefixcmp(ref->name, "refs/heads/"))
+		if (!send_mirror && !starts_with(ref->name, "refs/heads/"))
 			return NULL;
 		name = xstrdup(ref->name);
 	}
@@ -1248,7 +1248,7 @@ static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***ds
 			add_to_tips(&sent_tips, ref->peer_ref->new_sha1);
 		else
 			add_to_tips(&sent_tips, ref->old_sha1);
-		if (!prefixcmp(ref->name, "refs/tags/"))
+		if (starts_with(ref->name, "refs/tags/"))
 			string_list_append(&dst_tag, ref->name);
 	}
 	clear_commit_marks_many(sent_tips.nr, sent_tips.tip, TMP_MARK);
@@ -1257,7 +1257,7 @@ static void add_missing_tags(struct ref *src, struct ref **dst, struct ref ***ds
 
 	/* Collect tags they do not have. */
 	for (ref = src; ref; ref = ref->next) {
-		if (prefixcmp(ref->name, "refs/tags/"))
+		if (!starts_with(ref->name, "refs/tags/"))
 			continue; /* not a tag */
 		if (string_list_has_string(&dst_tag, ref->name))
 			continue; /* they already have it */
@@ -1481,7 +1481,7 @@ void set_ref_status_for_push(struct ref *remote_refs, int send_mirror,
 		 */
 
 		else if (!ref->deletion && !is_null_sha1(ref->old_sha1)) {
-			if (!prefixcmp(ref->name, "refs/tags/"))
+			if (starts_with(ref->name, "refs/tags/"))
 				reject_reason = REF_STATUS_REJECT_ALREADY_EXISTS;
 			else if (!has_sha1_file(ref->old_sha1))
 				reject_reason = REF_STATUS_REJECT_FETCH_FIRST;
@@ -1607,12 +1607,12 @@ static struct ref *get_local_ref(const char *name)
 	if (!name || name[0] == '\0')
 		return NULL;
 
-	if (!prefixcmp(name, "refs/"))
+	if (starts_with(name, "refs/"))
 		return alloc_ref(name);
 
-	if (!prefixcmp(name, "heads/") ||
-	    !prefixcmp(name, "tags/") ||
-	    !prefixcmp(name, "remotes/"))
+	if (starts_with(name, "heads/") ||
+	    starts_with(name, "tags/") ||
+	    starts_with(name, "remotes/"))
 		return alloc_ref_with_prefix("refs/", 5, name);
 
 	return alloc_ref_with_prefix("refs/heads/", 11, name);
@@ -1647,7 +1647,7 @@ int get_fetch_map(const struct ref *remote_refs,
 
 	for (rmp = &ref_map; *rmp; ) {
 		if ((*rmp)->peer_ref) {
-			if (prefixcmp((*rmp)->peer_ref->name, "refs/") ||
+			if (!starts_with((*rmp)->peer_ref->name, "refs/") ||
 			    check_refname_format((*rmp)->peer_ref->name, 0)) {
 				struct ref *ignore = *rmp;
 				error("* Ignoring funny ref '%s' locally",
@@ -1931,7 +1931,7 @@ struct ref *guess_remote_head(const struct ref *head,
 	/* Look for another ref that points there */
 	for (r = refs; r; r = r->next) {
 		if (r != head &&
-		    !prefixcmp(r->name, "refs/heads/") &&
+		    starts_with(r->name, "refs/heads/") &&
 		    !hashcmp(r->old_sha1, head->old_sha1)) {
 			*tail = copy_ref(r);
 			tail = &((*tail)->next);
diff --git a/revision.c b/revision.c
index a8adb3f..10854b0 100644
--- a/revision.c
+++ b/revision.c
@@ -1592,9 +1592,9 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 	    !strcmp(arg, "--tags") || !strcmp(arg, "--remotes") ||
 	    !strcmp(arg, "--reflog") || !strcmp(arg, "--not") ||
 	    !strcmp(arg, "--no-walk") || !strcmp(arg, "--do-walk") ||
-	    !strcmp(arg, "--bisect") || !prefixcmp(arg, "--glob=") ||
-	    !prefixcmp(arg, "--branches=") || !prefixcmp(arg, "--tags=") ||
-	    !prefixcmp(arg, "--remotes=") || !prefixcmp(arg, "--no-walk="))
+	    !strcmp(arg, "--bisect") || starts_with(arg, "--glob=") ||
+	    starts_with(arg, "--branches=") || starts_with(arg, "--tags=") ||
+	    starts_with(arg, "--remotes=") || starts_with(arg, "--no-walk="))
 	{
 		unkv[(*unkc)++] = arg;
 		return 1;
@@ -1617,7 +1617,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->max_count = atoi(argv[1]);
 		revs->no_walk = 0;
 		return 2;
-	} else if (!prefixcmp(arg, "-n")) {
+	} else if (starts_with(arg, "-n")) {
 		revs->max_count = atoi(arg + 2);
 		revs->no_walk = 0;
 	} else if ((argcount = parse_long_opt("max-age", argv, &optarg))) {
@@ -1677,7 +1677,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 	} else if (!strcmp(arg, "--author-date-order")) {
 		revs->sort_order = REV_SORT_BY_AUTHOR_DATE;
 		revs->topo_order = 1;
-	} else if (!prefixcmp(arg, "--early-output")) {
+	} else if (starts_with(arg, "--early-output")) {
 		int count = 100;
 		switch (arg[14]) {
 		case '=':
@@ -1702,13 +1702,13 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->min_parents = 2;
 	} else if (!strcmp(arg, "--no-merges")) {
 		revs->max_parents = 1;
-	} else if (!prefixcmp(arg, "--min-parents=")) {
+	} else if (starts_with(arg, "--min-parents=")) {
 		revs->min_parents = atoi(arg+14);
-	} else if (!prefixcmp(arg, "--no-min-parents")) {
+	} else if (starts_with(arg, "--no-min-parents")) {
 		revs->min_parents = 0;
-	} else if (!prefixcmp(arg, "--max-parents=")) {
+	} else if (starts_with(arg, "--max-parents=")) {
 		revs->max_parents = atoi(arg+14);
-	} else if (!prefixcmp(arg, "--no-max-parents")) {
+	} else if (starts_with(arg, "--no-max-parents")) {
 		revs->max_parents = -1;
 	} else if (!strcmp(arg, "--boundary")) {
 		revs->boundary = 1;
@@ -1758,7 +1758,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->verify_objects = 1;
 	} else if (!strcmp(arg, "--unpacked")) {
 		revs->unpacked = 1;
-	} else if (!prefixcmp(arg, "--unpacked=")) {
+	} else if (starts_with(arg, "--unpacked=")) {
 		die("--unpacked=<packfile> no longer supported.");
 	} else if (!strcmp(arg, "-r")) {
 		revs->diff = 1;
@@ -1783,7 +1783,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->verbose_header = 1;
 		revs->pretty_given = 1;
 		get_commit_format(arg+8, revs);
-	} else if (!prefixcmp(arg, "--pretty=") || !prefixcmp(arg, "--format=")) {
+	} else if (starts_with(arg, "--pretty=") || starts_with(arg, "--format=")) {
 		/*
 		 * Detached form ("--pretty X" as opposed to "--pretty=X")
 		 * not allowed, since the argument is optional.
@@ -1797,12 +1797,12 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->notes_opt.use_default_notes = 1;
 	} else if (!strcmp(arg, "--show-signature")) {
 		revs->show_signature = 1;
-	} else if (!prefixcmp(arg, "--show-notes=") ||
-		   !prefixcmp(arg, "--notes=")) {
+	} else if (starts_with(arg, "--show-notes=") ||
+		   starts_with(arg, "--notes=")) {
 		struct strbuf buf = STRBUF_INIT;
 		revs->show_notes = 1;
 		revs->show_notes_given = 1;
-		if (!prefixcmp(arg, "--show-notes")) {
+		if (starts_with(arg, "--show-notes")) {
 			if (revs->notes_opt.use_default_notes < 0)
 				revs->notes_opt.use_default_notes = 1;
 			strbuf_addstr(&buf, arg+13);
@@ -1845,7 +1845,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		revs->abbrev = 0;
 	} else if (!strcmp(arg, "--abbrev")) {
 		revs->abbrev = DEFAULT_ABBREV;
-	} else if (!prefixcmp(arg, "--abbrev=")) {
+	} else if (starts_with(arg, "--abbrev=")) {
 		revs->abbrev = strtoul(arg + 9, NULL, 10);
 		if (revs->abbrev < MINIMUM_ABBREV)
 			revs->abbrev = MINIMUM_ABBREV;
@@ -1984,15 +1984,15 @@ static int handle_revision_pseudo_opt(const char *submodule,
 		init_all_refs_cb(&cb, revs, *flags);
 		for_each_glob_ref(handle_one_ref, optarg, &cb);
 		return argcount;
-	} else if (!prefixcmp(arg, "--branches=")) {
+	} else if (starts_with(arg, "--branches=")) {
 		struct all_refs_cb cb;
 		init_all_refs_cb(&cb, revs, *flags);
 		for_each_glob_ref_in(handle_one_ref, arg + 11, "refs/heads/", &cb);
-	} else if (!prefixcmp(arg, "--tags=")) {
+	} else if (starts_with(arg, "--tags=")) {
 		struct all_refs_cb cb;
 		init_all_refs_cb(&cb, revs, *flags);
 		for_each_glob_ref_in(handle_one_ref, arg + 7, "refs/tags/", &cb);
-	} else if (!prefixcmp(arg, "--remotes=")) {
+	} else if (starts_with(arg, "--remotes=")) {
 		struct all_refs_cb cb;
 		init_all_refs_cb(&cb, revs, *flags);
 		for_each_glob_ref_in(handle_one_ref, arg + 10, "refs/remotes/", &cb);
@@ -2002,7 +2002,7 @@ static int handle_revision_pseudo_opt(const char *submodule,
 		*flags ^= UNINTERESTING | BOTTOM;
 	} else if (!strcmp(arg, "--no-walk")) {
 		revs->no_walk = REVISION_WALK_NO_WALK_SORTED;
-	} else if (!prefixcmp(arg, "--no-walk=")) {
+	} else if (starts_with(arg, "--no-walk=")) {
 		/*
 		 * Detached form ("--no-walk X" as opposed to "--no-walk=X")
 		 * not allowed, since the argument is optional.
diff --git a/send-pack.c b/send-pack.c
index fab62e3..142f211 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -109,7 +109,7 @@ static int receive_status(int in, struct ref *refs)
 	struct ref *hint;
 	int ret = 0;
 	char *line = packet_read_line(in, NULL);
-	if (prefixcmp(line, "unpack "))
+	if (!starts_with(line, "unpack "))
 		return error("did not receive remote status");
 	if (strcmp(line, "unpack ok")) {
 		error("unpack failed: %s", line + 7);
@@ -122,7 +122,7 @@ static int receive_status(int in, struct ref *refs)
 		line = packet_read_line(in, NULL);
 		if (!line)
 			break;
-		if (prefixcmp(line, "ok ") && prefixcmp(line, "ng ")) {
+		if (!starts_with(line, "ok ") && !starts_with(line, "ng ")) {
 			error("invalid ref status from remote: %s", line);
 			ret = -1;
 			break;
diff --git a/sequencer.c b/sequencer.c
index 06e52b4..90cac7b 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -41,7 +41,7 @@ static int is_cherry_picked_from_line(const char *buf, int len)
 	 * We only care that it looks roughly like (cherry picked from ...)
 	 */
 	return len > strlen(cherry_picked_prefix) + 1 &&
-		!prefixcmp(buf, cherry_picked_prefix) && buf[len - 1] == ')';
+		starts_with(buf, cherry_picked_prefix) && buf[len - 1] == ')';
 }
 
 /*
@@ -180,7 +180,7 @@ static char *get_encoding(const char *message)
 	while (*p && *p != '\n') {
 		for (eol = p + 1; *eol && *eol != '\n'; eol++)
 			; /* do nothing */
-		if (!prefixcmp(p, "encoding ")) {
+		if (starts_with(p, "encoding ")) {
 			char *result = xmalloc(eol - 8 - p);
 			strlcpy(result, p + 9, eol - 8 - p);
 			return result;
@@ -705,10 +705,10 @@ static struct commit *parse_insn_line(char *bol, char *eol, struct replay_opts *
 	char *end_of_object_name;
 	int saved, status, padding;
 
-	if (!prefixcmp(bol, "pick")) {
+	if (starts_with(bol, "pick")) {
 		action = REPLAY_PICK;
 		bol += strlen("pick");
-	} else if (!prefixcmp(bol, "revert")) {
+	} else if (starts_with(bol, "revert")) {
 		action = REPLAY_REVERT;
 		bol += strlen("revert");
 	} else
diff --git a/setup.c b/setup.c
index 5432a31..6c3f85f 100644
--- a/setup.c
+++ b/setup.c
@@ -82,7 +82,7 @@ int check_filename(const char *prefix, const char *arg)
 	const char *name;
 	struct stat st;
 
-	if (!prefixcmp(arg, ":/")) {
+	if (starts_with(arg, ":/")) {
 		if (arg[2] == '\0') /* ":/" is root dir, always exists */
 			return 1;
 		name = arg + 2;
@@ -304,7 +304,7 @@ const char *read_gitfile(const char *path)
 	if (len != st.st_size)
 		die("Error reading %s", path);
 	buf[len] = '\0';
-	if (prefixcmp(buf, "gitdir: "))
+	if (!starts_with(buf, "gitdir: "))
 		die("Invalid gitfile format: %s", path);
 	while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 		len--;
diff --git a/sha1_name.c b/sha1_name.c
index e9c2999..047477a 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -546,7 +546,7 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 		if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
 				&co_time, &co_tz, &co_cnt)) {
 			if (!len) {
-				if (!prefixcmp(real_ref, "refs/heads/")) {
+				if (starts_with(real_ref, "refs/heads/")) {
 					str = real_ref + 11;
 					len = strlen(real_ref + 11);
 				} else {
@@ -676,15 +676,15 @@ static int peel_onion(const char *name, int len, unsigned char *sha1)
 		return -1;
 
 	sp++; /* beginning of type name, or closing brace for empty */
-	if (!prefixcmp(sp, "commit}"))
+	if (starts_with(sp, "commit}"))
 		expected_type = OBJ_COMMIT;
-	else if (!prefixcmp(sp, "tag}"))
+	else if (starts_with(sp, "tag}"))
 		expected_type = OBJ_TAG;
-	else if (!prefixcmp(sp, "tree}"))
+	else if (starts_with(sp, "tree}"))
 		expected_type = OBJ_TREE;
-	else if (!prefixcmp(sp, "blob}"))
+	else if (starts_with(sp, "blob}"))
 		expected_type = OBJ_BLOB;
-	else if (!prefixcmp(sp, "object}"))
+	else if (starts_with(sp, "object}"))
 		expected_type = OBJ_ANY;
 	else if (sp[0] == '}')
 		expected_type = OBJ_NONE;
@@ -911,7 +911,7 @@ static int grab_nth_branch_switch(unsigned char *osha1, unsigned char *nsha1,
 	const char *match = NULL, *target = NULL;
 	size_t len;
 
-	if (!prefixcmp(message, "checkout: moving from ")) {
+	if (starts_with(message, "checkout: moving from ")) {
 		match = message + strlen("checkout: moving from ");
 		target = strstr(match, " to ");
 	}
@@ -1304,7 +1304,7 @@ static void diagnose_invalid_index_path(int stage,
 
 static char *resolve_relative_path(const char *rel)
 {
-	if (prefixcmp(rel, "./") && prefixcmp(rel, "../"))
+	if (!starts_with(rel, "./") && !starts_with(rel, "../"))
 		return NULL;
 
 	if (!startup_info)
diff --git a/shell.c b/shell.c
index 66350b2..5c0d47a 100644
--- a/shell.c
+++ b/shell.c
@@ -15,7 +15,7 @@ static int do_generic_cmd(const char *me, char *arg)
 	setup_path();
 	if (!arg || !(arg = sq_dequote(arg)))
 		die("bad argument");
-	if (prefixcmp(me, "git-"))
+	if (!starts_with(me, "git-"))
 		die("bad command");
 
 	my_argv[0] = me + 4;
diff --git a/submodule.c b/submodule.c
index 1905d75..613857e 100644
--- a/submodule.c
+++ b/submodule.c
@@ -201,7 +201,7 @@ void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 
 int submodule_config(const char *var, const char *value, void *cb)
 {
-	if (!prefixcmp(var, "submodule."))
+	if (starts_with(var, "submodule."))
 		return parse_submodule_config_option(var, value);
 	else if (!strcmp(var, "fetch.recursesubmodules")) {
 		config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
diff --git a/tag.c b/tag.c
index 78d272b..7b07921 100644
--- a/tag.c
+++ b/tag.c
@@ -86,7 +86,7 @@ int parse_tag_buffer(struct tag *item, const void *data, unsigned long size)
 		return -1;
 	bufptr += 48; /* "object " + sha1 + "\n" */
 
-	if (prefixcmp(bufptr, "type "))
+	if (!starts_with(bufptr, "type "))
 		return -1;
 	bufptr += 5;
 	nl = memchr(bufptr, '\n', tail - bufptr);
@@ -109,7 +109,7 @@ int parse_tag_buffer(struct tag *item, const void *data, unsigned long size)
 		item->tagged = NULL;
 	}
 
-	if (bufptr + 4 < tail && !prefixcmp(bufptr, "tag "))
+	if (bufptr + 4 < tail && starts_with(bufptr, "tag "))
 		; 		/* good */
 	else
 		return -1;
@@ -120,7 +120,7 @@ int parse_tag_buffer(struct tag *item, const void *data, unsigned long size)
 	item->tag = xmemdupz(bufptr, nl - bufptr);
 	bufptr = nl + 1;
 
-	if (bufptr + 7 < tail && !prefixcmp(bufptr, "tagger "))
+	if (bufptr + 7 < tail && starts_with(bufptr, "tagger "))
 		item->date = parse_tag_date(bufptr, tail);
 	else
 		item->date = 0;
@@ -160,8 +160,8 @@ size_t parse_signature(const char *buf, unsigned long size)
 {
 	char *eol;
 	size_t len = 0;
-	while (len < size && prefixcmp(buf + len, PGP_SIGNATURE) &&
-			prefixcmp(buf + len, PGP_MESSAGE)) {
+	while (len < size && !starts_with(buf + len, PGP_SIGNATURE) &&
+			!starts_with(buf + len, PGP_MESSAGE)) {
 		eol = memchr(buf + len, '\n', size - len);
 		len += eol ? eol - (buf + len) + 1 : size - len;
 	}
diff --git a/test-line-buffer.c b/test-line-buffer.c
index ef1d7ba..1e58f04 100644
--- a/test-line-buffer.c
+++ b/test-line-buffer.c
@@ -19,7 +19,7 @@ static void handle_command(const char *command, const char *arg, struct line_buf
 {
 	switch (*command) {
 	case 'b':
-		if (!prefixcmp(command, "binary ")) {
+		if (starts_with(command, "binary ")) {
 			struct strbuf sb = STRBUF_INIT;
 			strbuf_addch(&sb, '>');
 			buffer_read_binary(buf, &sb, strtouint32(arg));
@@ -28,12 +28,12 @@ static void handle_command(const char *command, const char *arg, struct line_buf
 			return;
 		}
 	case 'c':
-		if (!prefixcmp(command, "copy ")) {
+		if (starts_with(command, "copy ")) {
 			buffer_copy_bytes(buf, strtouint32(arg));
 			return;
 		}
 	case 's':
-		if (!prefixcmp(command, "skip ")) {
+		if (starts_with(command, "skip ")) {
 			buffer_skip_bytes(buf, strtouint32(arg));
 			return;
 		}
diff --git a/test-string-list.c b/test-string-list.c
index 00ce6c9..14bdf9d 100644
--- a/test-string-list.c
+++ b/test-string-list.c
@@ -38,7 +38,7 @@ static void write_list_compact(const struct string_list *list)
 static int prefix_cb(struct string_list_item *item, void *cb_data)
 {
 	const char *prefix = (const char *)cb_data;
-	return !prefixcmp(item->string, prefix);
+	return starts_with(item->string, prefix);
 }
 
 int main(int argc, char **argv)
diff --git a/transport-helper.c b/transport-helper.c
index 673b7c2..2010674 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -190,7 +190,7 @@ static struct child_process *get_helper(struct transport *transport)
 			data->export = 1;
 		else if (!strcmp(capname, "check-connectivity"))
 			data->check_connectivity = 1;
-		else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
+		else if (!data->refspecs && starts_with(capname, "refspec ")) {
 			ALLOC_GROW(refspecs,
 				   refspec_nr + 1,
 				   refspec_alloc);
@@ -199,17 +199,17 @@ static struct child_process *get_helper(struct transport *transport)
 			data->connect = 1;
 		} else if (!strcmp(capname, "signed-tags")) {
 			data->signed_tags = 1;
-		} else if (!prefixcmp(capname, "export-marks ")) {
+		} else if (starts_with(capname, "export-marks ")) {
 			struct strbuf arg = STRBUF_INIT;
 			strbuf_addstr(&arg, "--export-marks=");
 			strbuf_addstr(&arg, capname + strlen("export-marks "));
 			data->export_marks = strbuf_detach(&arg, NULL);
-		} else if (!prefixcmp(capname, "import-marks")) {
+		} else if (starts_with(capname, "import-marks")) {
 			struct strbuf arg = STRBUF_INIT;
 			strbuf_addstr(&arg, "--import-marks=");
 			strbuf_addstr(&arg, capname + strlen("import-marks "));
 			data->import_marks = strbuf_detach(&arg, NULL);
-		} else if (!prefixcmp(capname, "no-private-update")) {
+		} else if (starts_with(capname, "no-private-update")) {
 			data->no_private_update = 1;
 		} else if (mandatory) {
 			die("Unknown mandatory capability %s. This remote "
@@ -311,7 +311,7 @@ static int set_helper_option(struct transport *transport,
 
 	if (!strcmp(buf.buf, "ok"))
 		ret = 0;
-	else if (!prefixcmp(buf.buf, "error")) {
+	else if (starts_with(buf.buf, "error")) {
 		ret = -1;
 	} else if (!strcmp(buf.buf, "unsupported"))
 		ret = 1;
@@ -375,7 +375,7 @@ static int fetch_with_fetch(struct transport *transport,
 	while (1) {
 		recvline(data, &buf);
 
-		if (!prefixcmp(buf.buf, "lock ")) {
+		if (starts_with(buf.buf, "lock ")) {
 			const char *name = buf.buf + 5;
 			if (transport->pack_lockfile)
 				warning("%s also locked %s", data->name, name);
@@ -646,10 +646,10 @@ static int push_update_ref_status(struct strbuf *buf,
 	char *refname, *msg;
 	int status;
 
-	if (!prefixcmp(buf->buf, "ok ")) {
+	if (starts_with(buf->buf, "ok ")) {
 		status = REF_STATUS_OK;
 		refname = buf->buf + 3;
-	} else if (!prefixcmp(buf->buf, "error ")) {
+	} else if (starts_with(buf->buf, "error ")) {
 		status = REF_STATUS_REMOTE_REJECT;
 		refname = buf->buf + 6;
 	} else
diff --git a/transport.c b/transport.c
index 7202b77..8023956 100644
--- a/transport.c
+++ b/transport.c
@@ -169,13 +169,13 @@ static void set_upstreams(struct transport *transport, struct ref *refs,
 		remotename = ref->name;
 		tmp = resolve_ref_unsafe(localname, sha, 1, &flag);
 		if (tmp && flag & REF_ISSYMREF &&
-			!prefixcmp(tmp, "refs/heads/"))
+			starts_with(tmp, "refs/heads/"))
 			localname = tmp;
 
 		/* Both source and destination must be local branches. */
-		if (!localname || prefixcmp(localname, "refs/heads/"))
+		if (!localname || !starts_with(localname, "refs/heads/"))
 			continue;
-		if (!remotename || prefixcmp(remotename, "refs/heads/"))
+		if (!remotename || !starts_with(remotename, "refs/heads/"))
 			continue;
 
 		if (!pretend)
@@ -191,7 +191,7 @@ static void set_upstreams(struct transport *transport, struct ref *refs,
 
 static const char *rsync_url(const char *url)
 {
-	return prefixcmp(url, "rsync://") ? skip_prefix(url, "rsync:") : url;
+	return !starts_with(url, "rsync://") ? skip_prefix(url, "rsync:") : url;
 }
 
 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
@@ -296,8 +296,8 @@ static int write_one_ref(const char *name, const unsigned char *sha1,
 	FILE *f;
 
 	/* when called via for_each_ref(), flags is non-zero */
-	if (flags && prefixcmp(name, "refs/heads/") &&
-			prefixcmp(name, "refs/tags/"))
+	if (flags && !starts_with(name, "refs/heads/") &&
+			!starts_with(name, "refs/tags/"))
 		return 0;
 
 	strbuf_addstr(buf, name);
@@ -652,7 +652,7 @@ static void print_ok_ref_status(struct ref *ref, int porcelain)
 		print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
 	else if (is_null_sha1(ref->old_sha1))
 		print_ref_status('*',
-			(!prefixcmp(ref->name, "refs/tags/") ? "[new tag]" :
+			(starts_with(ref->name, "refs/tags/") ? "[new tag]" :
 			"[new branch]"),
 			ref, ref->peer_ref, NULL, porcelain);
 	else {
@@ -930,13 +930,13 @@ struct transport *transport_get(struct remote *remote, const char *url)
 
 		while (is_urlschemechar(p == url, *p))
 			p++;
-		if (!prefixcmp(p, "::"))
+		if (starts_with(p, "::"))
 			helper = xstrndup(url, p - url);
 	}
 
 	if (helper) {
 		transport_helper_init(ret, helper);
-	} else if (!prefixcmp(url, "rsync:")) {
+	} else if (starts_with(url, "rsync:")) {
 		ret->get_refs_list = get_refs_via_rsync;
 		ret->fetch = fetch_objs_via_rsync;
 		ret->push = rsync_transport_push;
@@ -949,11 +949,11 @@ struct transport *transport_get(struct remote *remote, const char *url)
 		ret->disconnect = close_bundle;
 		ret->smart_options = NULL;
 	} else if (!is_url(url)
-		|| !prefixcmp(url, "file://")
-		|| !prefixcmp(url, "git://")
-		|| !prefixcmp(url, "ssh://")
-		|| !prefixcmp(url, "git+ssh://")
-		|| !prefixcmp(url, "ssh+git://")) {
+		|| starts_with(url, "file://")
+		|| starts_with(url, "git://")
+		|| starts_with(url, "ssh://")
+		|| starts_with(url, "git+ssh://")
+		|| starts_with(url, "ssh+git://")) {
 		/* These are builtin smart transports. */
 		struct git_transport_data *data = xcalloc(1, sizeof(*data));
 		ret->data = data;
diff --git a/upload-pack.c b/upload-pack.c
index c989a73..dafd0e9 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -394,7 +394,7 @@ static int get_common_commits(void)
 			got_other = 0;
 			continue;
 		}
-		if (!prefixcmp(line, "have ")) {
+		if (starts_with(line, "have ")) {
 			switch (got_sha1(line+5, sha1)) {
 			case -1: /* they have what we do not */
 				got_other = 1;
@@ -540,7 +540,7 @@ static void receive_needs(void)
 		if (!line)
 			break;
 
-		if (!prefixcmp(line, "shallow ")) {
+		if (starts_with(line, "shallow ")) {
 			unsigned char sha1[20];
 			struct object *object;
 			if (get_sha1_hex(line + 8, sha1))
@@ -556,14 +556,14 @@ static void receive_needs(void)
 			}
 			continue;
 		}
-		if (!prefixcmp(line, "deepen ")) {
+		if (starts_with(line, "deepen ")) {
 			char *end;
 			depth = strtol(line + 7, &end, 0);
 			if (end == line + 7 || depth <= 0)
 				die("Invalid deepen: %s", line);
 			continue;
 		}
-		if (prefixcmp(line, "want ") ||
+		if (!starts_with(line, "want ") ||
 		    get_sha1_hex(line+5, sha1_buf))
 			die("git upload-pack: protocol error, "
 			    "expected to get sha, not '%s'", line);
@@ -815,7 +815,7 @@ int main(int argc, char **argv)
 			strict = 1;
 			continue;
 		}
-		if (!prefixcmp(arg, "--timeout=")) {
+		if (starts_with(arg, "--timeout=")) {
 			timeout = atoi(arg+10);
 			daemon_mode = 1;
 			continue;
diff --git a/wt-status.c b/wt-status.c
index b4e44ba..f3c0088 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -803,7 +803,7 @@ static void wt_status_print_tracking(struct wt_status *s)
 	int i;
 
 	assert(s->branch && !s->is_initial);
-	if (prefixcmp(s->branch, "refs/heads/"))
+	if (!starts_with(s->branch, "refs/heads/"))
 		return;
 	branch = branch_get(s->branch + 11);
 	if (!format_tracking_info(branch, &sb))
@@ -1062,9 +1062,9 @@ static char *read_and_strip_branch(const char *path)
 		strbuf_setlen(&sb, sb.len - 1);
 	if (!sb.len)
 		goto got_nothing;
-	if (!prefixcmp(sb.buf, "refs/heads/"))
+	if (starts_with(sb.buf, "refs/heads/"))
 		strbuf_remove(&sb,0, strlen("refs/heads/"));
-	else if (!prefixcmp(sb.buf, "refs/"))
+	else if (starts_with(sb.buf, "refs/"))
 		;
 	else if (!get_sha1_hex(sb.buf, sha1)) {
 		const char *abbrev;
@@ -1094,7 +1094,7 @@ static int grab_1st_switch(unsigned char *osha1, unsigned char *nsha1,
 	struct grab_1st_switch_cbdata *cb = cb_data;
 	const char *target = NULL, *end;
 
-	if (prefixcmp(message, "checkout: moving from "))
+	if (!starts_with(message, "checkout: moving from "))
 		return 0;
 	message += strlen("checkout: moving from ");
 	target = strstr(message, " to ");
@@ -1129,9 +1129,9 @@ static void wt_status_get_detached_from(struct wt_status_state *state)
 	     ((commit = lookup_commit_reference_gently(sha1, 1)) != NULL &&
 	      !hashcmp(cb.nsha1, commit->object.sha1)))) {
 		int ofs;
-		if (!prefixcmp(ref, "refs/tags/"))
+		if (starts_with(ref, "refs/tags/"))
 			ofs = strlen("refs/tags/");
-		else if (!prefixcmp(ref, "refs/remotes/"))
+		else if (starts_with(ref, "refs/remotes/"))
 			ofs = strlen("refs/remotes/");
 		else
 			ofs = 0;
@@ -1220,7 +1220,7 @@ void wt_status_print(struct wt_status *s)
 	if (s->branch) {
 		const char *on_what = _("On branch ");
 		const char *branch_name = s->branch;
-		if (!prefixcmp(branch_name, "refs/heads/"))
+		if (starts_with(branch_name, "refs/heads/"))
 			branch_name += 11;
 		else if (!strcmp(branch_name, "HEAD")) {
 			branch_status_color = color(WT_STATUS_NOBRANCH, s);
@@ -1421,7 +1421,7 @@ static void wt_shortstatus_print_tracking(struct wt_status *s)
 		return;
 	branch_name = s->branch;
 
-	if (!prefixcmp(branch_name, "refs/heads/"))
+	if (starts_with(branch_name, "refs/heads/"))
 		branch_name += 11;
 	else if (!strcmp(branch_name, "HEAD")) {
 		branch_name = _("HEAD (no branch)");
-- 
cgit v0.10.2-6-g49f6