1 files changed, 153 insertions, 123 deletions

diff --git a/diff-no-index.c b/diff-no-index.c
index 4ebc1db..0320605 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -15,8 +15,9 @@
 #include "log-tree.h"
 #include "builtin.h"
 #include "string-list.h"
+#include "dir.h"
 
-static int read_directory(const char *path, struct string_list *list)
+static int read_directory_contents(const char *path, struct string_list *list)
 {
 	DIR *dir;
 	struct dirent *e;
@@ -25,24 +26,31 @@ static int read_directory(const char *path, struct string_list *list)
 		return error("Could not open directory %s", path);
 
 	while ((e = readdir(dir)))
-		if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
-			string_list_insert(e->d_name, list);
+		if (!is_dot_or_dotdot(e->d_name))
+			string_list_insert(list, e->d_name);
 
 	closedir(dir);
 	return 0;
 }
 
+/*
+ * This should be "(standard input)" or something, but it will
+ * probably expose many more breakages in the way no-index code
+ * is bolted onto the diff callchain.
+ */
+static const char file_from_standard_input[] = "-";
+
 static int get_mode(const char *path, int *mode)
 {
 	struct stat st;
 
 	if (!path || !strcmp(path, "/dev/null"))
 		*mode = 0;
-#ifdef _WIN32
+#ifdef GIT_WINDOWS_NATIVE
 	else if (!strcasecmp(path, "nul"))
 		*mode = 0;
 #endif
-	else if (!strcmp(path, "-"))
+	else if (path == file_from_standard_input)
 		*mode = create_ce_mode(0666);
 	else if (lstat(path, &st))
 		return error("Could not access '%s'", path);
@@ -51,77 +59,129 @@ static int get_mode(const char *path, int *mode)
 	return 0;
 }
 
+static int populate_from_stdin(struct diff_filespec *s)
+{
+	struct strbuf buf = STRBUF_INIT;
+	size_t size = 0;
+
+	if (strbuf_read(&buf, 0, 0) < 0)
+		return error("error while reading from stdin %s",
+				     strerror(errno));
+
+	s->should_munmap = 0;
+	s->data = strbuf_detach(&buf, &size);
+	s->size = size;
+	s->should_free = 1;
+	s->is_stdin = 1;
+	return 0;
+}
+
+static struct diff_filespec *noindex_filespec(const char *name, int mode)
+{
+	struct diff_filespec *s;
+
+	if (!name)
+		name = "/dev/null";
+	s = alloc_filespec(name);
+	fill_filespec(s, null_sha1, 0, mode);
+	if (name == file_from_standard_input)
+		populate_from_stdin(s);
+	return s;
+}
+
 static int queue_diff(struct diff_options *o,
-		const char *name1, const char *name2)
+		      const char *name1, const char *name2)
 {
 	int mode1 = 0, mode2 = 0;
 
 	if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
 		return -1;
 
-	if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
-		return error("file/directory conflict: %s, %s", name1, name2);
+	if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
+		struct diff_filespec *d1, *d2;
 
-	if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
-		char buffer1[PATH_MAX], buffer2[PATH_MAX];
-		struct string_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
-		int len1 = 0, len2 = 0, i1, i2, ret = 0;
+		if (S_ISDIR(mode1)) {
+			/* 2 is file that is created */
+			d1 = noindex_filespec(NULL, 0);
+			d2 = noindex_filespec(name2, mode2);
+			name2 = NULL;
+			mode2 = 0;
+		} else {
+			/* 1 is file that is deleted */
+			d1 = noindex_filespec(name1, mode1);
+			d2 = noindex_filespec(NULL, 0);
+			name1 = NULL;
+			mode1 = 0;
+		}
+		/* emit that file */
+		diff_queue(&diff_queued_diff, d1, d2);
+
+		/* and then let the entire directory be created or deleted */
+	}
 
-		if (name1 && read_directory(name1, &p1))
+	if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
+		struct strbuf buffer1 = STRBUF_INIT;
+		struct strbuf buffer2 = STRBUF_INIT;
+		struct string_list p1 = STRING_LIST_INIT_DUP;
+		struct string_list p2 = STRING_LIST_INIT_DUP;
+		int i1, i2, ret = 0;
+		size_t len1 = 0, len2 = 0;
+
+		if (name1 && read_directory_contents(name1, &p1))
 			return -1;
-		if (name2 && read_directory(name2, &p2)) {
+		if (name2 && read_directory_contents(name2, &p2)) {
 			string_list_clear(&p1, 0);
 			return -1;
 		}
 
 		if (name1) {
-			len1 = strlen(name1);
-			if (len1 > 0 && name1[len1 - 1] == '/')
-				len1--;
-			memcpy(buffer1, name1, len1);
-			buffer1[len1++] = '/';
+			strbuf_addstr(&buffer1, name1);
+			if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
+				strbuf_addch(&buffer1, '/');
+			len1 = buffer1.len;
 		}
 
 		if (name2) {
-			len2 = strlen(name2);
-			if (len2 > 0 && name2[len2 - 1] == '/')
-				len2--;
-			memcpy(buffer2, name2, len2);
-			buffer2[len2++] = '/';
+			strbuf_addstr(&buffer2, name2);
+			if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
+				strbuf_addch(&buffer2, '/');
+			len2 = buffer2.len;
 		}
 
 		for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
 			const char *n1, *n2;
 			int comp;
 
+			strbuf_setlen(&buffer1, len1);
+			strbuf_setlen(&buffer2, len2);
+
 			if (i1 == p1.nr)
 				comp = 1;
 			else if (i2 == p2.nr)
 				comp = -1;
 			else
-				comp = strcmp(p1.items[i1].string,
-					p2.items[i2].string);
+				comp = strcmp(p1.items[i1].string, p2.items[i2].string);
 
 			if (comp > 0)
 				n1 = NULL;
 			else {
-				n1 = buffer1;
-				strncpy(buffer1 + len1, p1.items[i1++].string,
-						PATH_MAX - len1);
+				strbuf_addstr(&buffer1, p1.items[i1++].string);
+				n1 = buffer1.buf;
 			}
 
 			if (comp < 0)
 				n2 = NULL;
 			else {
-				n2 = buffer2;
-				strncpy(buffer2 + len2, p2.items[i2++].string,
-						PATH_MAX - len2);
+				strbuf_addstr(&buffer2, p2.items[i2++].string);
+				n2 = buffer2.buf;
 			}
 
 			ret = queue_diff(o, n1, n2);
 		}
 		string_list_clear(&p1, 0);
 		string_list_clear(&p2, 0);
+		strbuf_release(&buffer1);
+		strbuf_release(&buffer2);
 
 		return ret;
 	} else {
@@ -134,142 +194,112 @@ static int queue_diff(struct diff_options *o,
 			tmp_c = name1; name1 = name2; name2 = tmp_c;
 		}
 
-		if (!name1)
-			name1 = "/dev/null";
-		if (!name2)
-			name2 = "/dev/null";
-		d1 = alloc_filespec(name1);
-		d2 = alloc_filespec(name2);
-		fill_filespec(d1, null_sha1, mode1);
-		fill_filespec(d2, null_sha1, mode2);
-
+		d1 = noindex_filespec(name1, mode1);
+		d2 = noindex_filespec(name2, mode2);
 		diff_queue(&diff_queued_diff, d1, d2);
 		return 0;
 	}
 }
 
-static int path_outside_repo(const char *path)
+/* append basename of F to D */
+static void append_basename(struct strbuf *path, const char *dir, const char *file)
 {
-	/*
-	 * We have already done setup_git_directory_gently() so we
-	 * know we are inside a git work tree already.
-	 */
-	const char *work_tree;
-	size_t len;
+	const char *tail = strrchr(file, '/');
 
-	if (!is_absolute_path(path))
-		return 0;
-	work_tree = get_git_work_tree();
-	len = strlen(work_tree);
-	if (strncmp(path, work_tree, len) ||
-	    (path[len] != '\0' && path[len] != '/'))
-		return 1;
-	return 0;
+	strbuf_addstr(path, dir);
+	while (path->len && path->buf[path->len - 1] == '/')
+		path->len--;
+	strbuf_addch(path, '/');
+	strbuf_addstr(path, tail ? tail + 1 : file);
 }
 
-void diff_no_index(struct rev_info *revs,
-		   int argc, const char **argv,
-		   int nongit, const char *prefix)
+/*
+ * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
+ * Note that we append the basename of F to D/, so "diff a/b/file D"
+ * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
+ */
+static void fixup_paths(const char **path, struct strbuf *replacement)
 {
-	int i;
-	int no_index = 0;
-	unsigned options = 0;
-
-	/* Were we asked to do --no-index explicitly? */
-	for (i = 1; i < argc; i++) {
-		if (!strcmp(argv[i], "--")) {
-			i++;
-			break;
-		}
-		if (!strcmp(argv[i], "--no-index"))
-			no_index = 1;
-		if (argv[i][0] != '-')
-			break;
+	unsigned int isdir0, isdir1;
+
+	if (path[0] == file_from_standard_input ||
+	    path[1] == file_from_standard_input)
+		return;
+	isdir0 = is_directory(path[0]);
+	isdir1 = is_directory(path[1]);
+	if (isdir0 == isdir1)
+		return;
+	if (isdir0) {
+		append_basename(replacement, path[0], path[1]);
+		path[0] = replacement->buf;
+	} else {
+		append_basename(replacement, path[1], path[0]);
+		path[1] = replacement->buf;
 	}
+}
 
-	if (!no_index && !nongit) {
-		/*
-		 * Inside a git repository, without --no-index.  Only
-		 * when a path outside the repository is given,
-		 * e.g. "git diff /var/tmp/[12]", or "git diff
-		 * Makefile /var/tmp/Makefile", allow it to be used as
-		 * a colourful "diff" replacement.
-		 */
-		if ((argc != i + 2) ||
-		    (!path_outside_repo(argv[i]) &&
-		     !path_outside_repo(argv[i+1])))
-			return;
-	}
-	if (argc != i + 2)
-		die("git diff %s takes two paths",
-		    no_index ? "--no-index" : "[--no-index]");
+void diff_no_index(struct rev_info *revs,
+		   int argc, const char **argv,
+		   const char *prefix)
+{
+	int i, prefixlen;
+	const char *paths[2];
+	struct strbuf replacement = STRBUF_INIT;
 
 	diff_setup(&revs->diffopt);
 	for (i = 1; i < argc - 2; ) {
 		int j;
 		if (!strcmp(argv[i], "--no-index"))
 			i++;
-		else if (!strcmp(argv[i], "-q")) {
-			options |= DIFF_SILENT_ON_REMOVED;
-			i++;
-		}
 		else if (!strcmp(argv[i], "--"))
 			i++;
 		else {
 			j = diff_opt_parse(&revs->diffopt, argv + i, argc - i);
-			if (!j)
+			if (j <= 0)
 				die("invalid diff option/value: %s", argv[i]);
 			i += j;
 		}
 	}
 
-	/*
-	 * If the user asked for our exit code then don't start a
-	 * pager or we would end up reporting its exit code instead.
-	 */
-	if (!DIFF_OPT_TST(&revs->diffopt, EXIT_WITH_STATUS))
-		setup_pager();
-
-	if (prefix) {
-		int len = strlen(prefix);
-
-		revs->diffopt.paths = xcalloc(2, sizeof(char *));
-		for (i = 0; i < 2; i++) {
-			const char *p = argv[argc - 2 + i];
+	prefixlen = prefix ? strlen(prefix) : 0;
+	for (i = 0; i < 2; i++) {
+		const char *p = argv[argc - 2 + i];
+		if (!strcmp(p, "-"))
 			/*
-			 * stdin should be spelled as '-'; if you have
-			 * path that is '-', spell it as ./-.
+			 * stdin should be spelled as "-"; if you have
+			 * path that is "-", spell it as "./-".
 			 */
-			p = (strcmp(p, "-")
-			     ? xstrdup(prefix_filename(prefix, len, p))
-			     : p);
-			revs->diffopt.paths[i] = p;
-		}
+			p = file_from_standard_input;
+		else if (prefixlen)
+			p = xstrdup(prefix_filename(prefix, prefixlen, p));
+		paths[i] = p;
 	}
-	else
-		revs->diffopt.paths = argv + argc - 2;
-	revs->diffopt.nr_paths = 2;
+
+	fixup_paths(paths, &replacement);
+
 	revs->diffopt.skip_stat_unmatch = 1;
 	if (!revs->diffopt.output_format)
 		revs->diffopt.output_format = DIFF_FORMAT_PATCH;
 
-	DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
 	DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
 
 	revs->max_count = -2;
-	if (diff_setup_done(&revs->diffopt) < 0)
-		die("diff_setup_done failed");
+	diff_setup_done(&revs->diffopt);
 
-	if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
-		       revs->diffopt.paths[1]))
+	setup_diff_pager(&revs->diffopt);
+	DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
+
+	if (queue_diff(&revs->diffopt, paths[0], paths[1]))
 		exit(1);
 	diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
 	diffcore_std(&revs->diffopt);
 	diff_flush(&revs->diffopt);
 
+	strbuf_release(&replacement);
+
 	/*
 	 * The return code for --no-index imitates diff(1):
 	 * 0 = no changes, 1 = changes, else error
 	 */
-	exit(revs->diffopt.found_changes);
+	exit(diff_result_code(&revs->diffopt, 0));
 }