1 files changed, 156 insertions, 0 deletions
diff --git a/builtin/hash-object.c b/builtin/hash-object.c
new file mode 100644
index 0000000..207b90c
--- /dev/null
+++ b/builtin/hash-object.c
@@ -0,0 +1,156 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ * Copyright (C) Junio C Hamano, 2005
+ */
+#include "builtin.h"
+#include "blob.h"
+#include "quote.h"
+#include "parse-options.h"
+#include "exec_cmd.h"
+
+/*
+ * This is to create corrupt objects for debugging and as such it
+ * needs to bypass the data conversion performed by, and the type
+ * limitation imposed by, index_fd() and its callees.
+ */
+static int hash_literally(unsigned char *sha1, int fd, const char *type, unsigned flags)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int ret;
+
+	if (strbuf_read(&buf, fd, 4096) < 0)
+		ret = -1;
+	else if (flags & HASH_WRITE_OBJECT)
+		ret = write_sha1_file(buf.buf, buf.len, type, sha1);
+	else
+		ret = hash_sha1_file(buf.buf, buf.len, type, sha1);
+	strbuf_release(&buf);
+	return ret;
+}
+
+static void hash_fd(int fd, const char *type, const char *path, unsigned flags,
+		    int literally)
+{
+	struct stat st;
+	unsigned char sha1[20];
+
+	if (fstat(fd, &st) < 0 ||
+	    (literally
+	     ? hash_literally(sha1, fd, type, flags)
+	     : index_fd(sha1, fd, &st, type_from_string(type), path, flags)))
+		die((flags & HASH_WRITE_OBJECT)
+		    ? "Unable to add %s to database"
+		    : "Unable to hash %s", path);
+	printf("%s\n", sha1_to_hex(sha1));
+	maybe_flush_or_die(stdout, "hash to stdout");
+}
+
+static void hash_object(const char *path, const char *type, const char *vpath,
+			unsigned flags, int literally)
+{
+	int fd;
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		die_errno("Cannot open '%s'", path);
+	hash_fd(fd, type, vpath, flags, literally);
+}
+
+static void hash_stdin_paths(const char *type, int no_filters, unsigned flags,
+			     int literally)
+{
+	struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
+
+	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
+		if (buf.buf[0] == '"') {
+			strbuf_reset(&nbuf);
+			if (unquote_c_style(&nbuf, buf.buf, NULL))
+				die("line is badly quoted");
+			strbuf_swap(&buf, &nbuf);
+		}
+		hash_object(buf.buf, type, no_filters ? NULL : buf.buf, flags,
+			    literally);
+	}
+	strbuf_release(&buf);
+	strbuf_release(&nbuf);
+}
+
+int cmd_hash_object(int argc, const char **argv, const char *prefix)
+{
+	static const char * const hash_object_usage[] = {
+		N_("git hash-object [-t <type>] [-w] [--path=<file> | --no-filters] [--stdin] [--] <file>..."),
+		N_("git hash-object  --stdin-paths < <list-of-paths>"),
+		NULL
+	};
+	const char *type = blob_type;
+	int hashstdin = 0;
+	int stdin_paths = 0;
+	int no_filters = 0;
+	int literally = 0;
+	unsigned flags = HASH_FORMAT_CHECK;
+	const char *vpath = NULL;
+	const struct option hash_object_options[] = {
+		OPT_STRING('t', NULL, &type, N_("type"), N_("object type")),
+		OPT_BIT('w', NULL, &flags, N_("write the object into the object database"),
+			HASH_WRITE_OBJECT),
+		OPT_COUNTUP( 0 , "stdin", &hashstdin, N_("read the object from stdin")),
+		OPT_BOOL( 0 , "stdin-paths", &stdin_paths, N_("read file names from stdin")),
+		OPT_BOOL( 0 , "no-filters", &no_filters, N_("store file as is without filters")),
+		OPT_BOOL( 0, "literally", &literally, N_("just hash any random garbage to create corrupt objects for debugging Git")),
+		OPT_STRING( 0 , "path", &vpath, N_("file"), N_("process file as it were from this path")),
+		OPT_END()
+	};
+	int i;
+	int prefix_length = -1;
+	const char *errstr = NULL;
+
+	argc = parse_options(argc, argv, NULL, hash_object_options,
+			     hash_object_usage, 0);
+
+	if (flags & HASH_WRITE_OBJECT) {
+		prefix = setup_git_directory();
+		prefix_length = prefix ? strlen(prefix) : 0;
+		if (vpath && prefix)
+			vpath = prefix_filename(prefix, prefix_length, vpath);
+	}
+
+	git_config(git_default_config, NULL);
+
+	if (stdin_paths) {
+		if (hashstdin)
+			errstr = "Can't use --stdin-paths with --stdin";
+		else if (argc)
+			errstr = "Can't specify files with --stdin-paths";
+		else if (vpath)
+			errstr = "Can't use --stdin-paths with --path";
+	}
+	else {
+		if (hashstdin > 1)
+			errstr = "Multiple --stdin arguments are not supported";
+		if (vpath && no_filters)
+			errstr = "Can't use --path with --no-filters";
+	}
+
+	if (errstr) {
+		error("%s", errstr);
+		usage_with_options(hash_object_usage, hash_object_options);
+	}
+
+	if (hashstdin)
+		hash_fd(0, type, vpath, flags, literally);
+
+	for (i = 0 ; i < argc; i++) {
+		const char *arg = argv[i];
+
+		if (0 <= prefix_length)
+			arg = prefix_filename(prefix, prefix_length, arg);
+		hash_object(arg, type, no_filters ? NULL : vpath ? vpath : arg,
+			    flags, literally);
+	}
+
+	if (stdin_paths)
+		hash_stdin_paths(type, no_filters, flags, literally);
+
+	return 0;
+}