1 files changed, 347 insertions, 156 deletions

diff --git a/sha1_file.c b/sha1_file.c
index b231b62784..50896ff1eb 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -208,44 +208,25 @@ const char *sha1_file_name(const unsigned char *sha1)
  * provided by the caller.  which should be "pack" or "idx".
  */
 static char *sha1_get_pack_name(const unsigned char *sha1,
-				char **name, char **base, const char *which)
+				struct strbuf *buf,
+				const char *which)
 {
-	static const char hex[] = "0123456789abcdef";
-	char *buf;
-	int i;
-
-	if (!*base) {
-		const char *sha1_file_directory = get_object_directory();
-		int len = strlen(sha1_file_directory);
-		*base = xmalloc(len + 60);
-		sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
-			sha1_file_directory, which);
-		*name = *base + len + 11;
-	}
-
-	buf = *name;
-
-	for (i = 0; i < 20; i++) {
-		unsigned int val = *sha1++;
-		*buf++ = hex[val >> 4];
-		*buf++ = hex[val & 0xf];
-	}
-
-	return *base;
+	strbuf_reset(buf);
+	strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(),
+		    sha1_to_hex(sha1), which);
+	return buf->buf;
 }
 
 char *sha1_pack_name(const unsigned char *sha1)
 {
-	static char *name, *base;
-
-	return sha1_get_pack_name(sha1, &name, &base, "pack");
+	static struct strbuf buf = STRBUF_INIT;
+	return sha1_get_pack_name(sha1, &buf, "pack");
 }
 
 char *sha1_pack_index_name(const unsigned char *sha1)
 {
-	static char *name, *base;
-
-	return sha1_get_pack_name(sha1, &name, &base, "idx");
+	static struct strbuf buf = STRBUF_INIT;
+	return sha1_get_pack_name(sha1, &buf, "idx");
 }
 
 struct alternate_object_database *alt_odb_list;
@@ -401,13 +382,46 @@ void read_info_alternates(const char * relative_base, int depth)
 void add_to_alternates_file(const char *reference)
 {
 	struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
-	int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
-	char *alt = mkpath("%s\n", reference);
-	write_or_die(fd, alt, strlen(alt));
-	if (commit_lock_file(lock))
-		die("could not close alternates file");
-	if (alt_odb_tail)
-		link_alt_odb_entries(alt, strlen(alt), '\n', NULL, 0);
+	char *alts = git_pathdup("objects/info/alternates");
+	FILE *in, *out;
+
+	hold_lock_file_for_update(lock, alts, LOCK_DIE_ON_ERROR);
+	out = fdopen_lock_file(lock, "w");
+	if (!out)
+		die_errno("unable to fdopen alternates lockfile");
+
+	in = fopen(alts, "r");
+	if (in) {
+		struct strbuf line = STRBUF_INIT;
+		int found = 0;
+
+		while (strbuf_getline(&line, in, '\n') != EOF) {
+			if (!strcmp(reference, line.buf)) {
+				found = 1;
+				break;
+			}
+			fprintf_or_die(out, "%s\n", line.buf);
+		}
+
+		strbuf_release(&line);
+		fclose(in);
+
+		if (found) {
+			rollback_lock_file(lock);
+			lock = NULL;
+		}
+	}
+	else if (errno != ENOENT)
+		die_errno("unable to read alternates file");
+
+	if (lock) {
+		fprintf_or_die(out, "%s\n", reference);
+		if (commit_lock_file(lock))
+			die_errno("unable to move new alternates file into place");
+		if (alt_odb_tail)
+			link_alt_odb_entries(reference, strlen(reference), '\n', NULL, 0);
+	}
+	free(alts);
 }
 
 int foreach_alt_odb(alt_odb_fn fn, void *cb)
@@ -440,6 +454,7 @@ void prepare_alt_odb(void)
 	read_info_alternates(get_object_directory(), 0);
 }
 
+/* Returns 1 if we have successfully freshened the file, 0 otherwise. */
 static int freshen_file(const char *fn)
 {
 	struct utimbuf t;
@@ -447,11 +462,18 @@ static int freshen_file(const char *fn)
 	return !utime(fn, &t);
 }
 
+/*
+ * All of the check_and_freshen functions return 1 if the file exists and was
+ * freshened (if freshening was requested), 0 otherwise. If they return
+ * 0, you should not assume that it is safe to skip a write of the object (it
+ * either does not exist on disk, or has a stale mtime and may be subject to
+ * pruning).
+ */
 static int check_and_freshen_file(const char *fn, int freshen)
 {
 	if (access(fn, F_OK))
 		return 0;
-	if (freshen && freshen_file(fn))
+	if (freshen && !freshen_file(fn))
 		return 0;
 	return 1;
 }
@@ -630,13 +652,15 @@ static int check_packed_git_idx(const char *path, struct packed_git *p)
 int open_pack_index(struct packed_git *p)
 {
 	char *idx_name;
+	size_t len;
 	int ret;
 
 	if (p->index_data)
 		return 0;
 
-	idx_name = xstrdup(p->pack_name);
-	strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
+	if (!strip_suffix(p->pack_name, ".pack", &len))
+		die("BUG: pack_name does not end in .pack");
+	idx_name = xstrfmt("%.*s.idx", (int)len, p->pack_name);
 	ret = check_packed_git_idx(idx_name, p);
 	free(idx_name);
 	return ret;
@@ -704,8 +728,8 @@ static void mmap_limit_check(size_t length)
 		    (uintmax_t)length, (uintmax_t)limit);
 }
 
-void *xmmap(void *start, size_t length,
-	int prot, int flags, int fd, off_t offset)
+void *xmmap_gently(void *start, size_t length,
+		  int prot, int flags, int fd, off_t offset)
 {
 	void *ret;
 
@@ -716,12 +740,19 @@ void *xmmap(void *start, size_t length,
 			return NULL;
 		release_pack_memory(length);
 		ret = mmap(start, length, prot, flags, fd, offset);
-		if (ret == MAP_FAILED)
-			die_errno("Out of memory? mmap failed");
 	}
 	return ret;
 }
 
+void *xmmap(void *start, size_t length,
+	int prot, int flags, int fd, off_t offset)
+{
+	void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
+	if (ret == MAP_FAILED)
+		die_errno("mmap failed");
+	return ret;
+}
+
 void close_pack_windows(struct packed_git *p)
 {
 	while (p->windows) {
@@ -738,6 +769,37 @@ void close_pack_windows(struct packed_git *p)
 	}
 }
 
+static int close_pack_fd(struct packed_git *p)
+{
+	if (p->pack_fd < 0)
+		return 0;
+
+	close(p->pack_fd);
+	pack_open_fds--;
+	p->pack_fd = -1;
+
+	return 1;
+}
+
+static void close_pack(struct packed_git *p)
+{
+	close_pack_windows(p);
+	close_pack_fd(p);
+	close_pack_index(p);
+}
+
+void close_all_packs(void)
+{
+	struct packed_git *p;
+
+	for (p = packed_git; p; p = p->next)
+		if (p->do_not_close)
+			die("BUG! Want to close pack marked 'do-not-close'");
+		else
+			close_pack(p);
+}
+
+
 /*
  * The LRU pack is the one with the oldest MRU window, preferring packs
  * with no used windows, or the oldest mtime if it has no windows allocated.
@@ -805,12 +867,8 @@ static int close_one_pack(void)
 		find_lru_pack(p, &lru_p, &mru_w, &accept_windows_inuse);
 	}
 
-	if (lru_p) {
-		close(lru_p->pack_fd);
-		pack_open_fds--;
-		lru_p->pack_fd = -1;
-		return 1;
-	}
+	if (lru_p)
+		return close_pack_fd(lru_p);
 
 	return 0;
 }
@@ -850,12 +908,7 @@ void free_pack_by_name(const char *pack_name)
 		p = *pp;
 		if (strcmp(pack_name, p->pack_name) == 0) {
 			clear_delta_base_cache();
-			close_pack_windows(p);
-			if (p->pack_fd != -1) {
-				close(p->pack_fd);
-				pack_open_fds--;
-			}
-			close_pack_index(p);
+			close_pack(p);
 			free(p->bad_object_sha1);
 			*pp = p->next;
 			if (last_found_pack == p)
@@ -989,11 +1042,7 @@ static int open_packed_git(struct packed_git *p)
 {
 	if (!open_packed_git_1(p))
 		return 0;
-	if (p->pack_fd != -1) {
-		close(p->pack_fd);
-		pack_open_fds--;
-		p->pack_fd = -1;
-	}
+	close_pack_fd(p);
 	return -1;
 }
 
@@ -1059,11 +1108,8 @@ unsigned char *use_pack(struct packed_git *p,
 					p->pack_name,
 					strerror(errno));
 			if (!win->offset && win->len == p->pack_size
-				&& !p->do_not_close) {
-				close(p->pack_fd);
-				pack_open_fds--;
-				p->pack_fd = -1;
-			}
+				&& !p->do_not_close)
+				close_pack_fd(p);
 			pack_mmap_calls++;
 			pack_open_windows++;
 			if (pack_mapped > peak_pack_mapped)
@@ -1098,11 +1144,12 @@ static void try_to_free_pack_memory(size_t size)
 	release_pack_memory(size);
 }
 
-struct packed_git *add_packed_git(const char *path, int path_len, int local)
+struct packed_git *add_packed_git(const char *path, size_t path_len, int local)
 {
 	static int have_set_try_to_free_routine;
 	struct stat st;
-	struct packed_git *p = alloc_packed_git(path_len + 2);
+	size_t alloc;
+	struct packed_git *p;
 
 	if (!have_set_try_to_free_routine) {
 		have_set_try_to_free_routine = 1;
@@ -1113,18 +1160,22 @@ struct packed_git *add_packed_git(const char *path, int path_len, int local)
 	 * Make sure a corresponding .pack file exists and that
 	 * the index looks sane.
 	 */
-	path_len -= strlen(".idx");
-	if (path_len < 1) {
-		free(p);
+	if (!strip_suffix_mem(path, &path_len, ".idx"))
 		return NULL;
-	}
+
+	/*
+	 * ".pack" is long enough to hold any suffix we're adding (and
+	 * the use xsnprintf double-checks that)
+	 */
+	alloc = path_len + strlen(".pack") + 1;
+	p = alloc_packed_git(alloc);
 	memcpy(p->pack_name, path, path_len);
 
-	strcpy(p->pack_name + path_len, ".keep");
+	xsnprintf(p->pack_name + path_len, alloc - path_len, ".keep");
 	if (!access(p->pack_name, F_OK))
 		p->pack_keep = 1;
 
-	strcpy(p->pack_name + path_len, ".pack");
+	xsnprintf(p->pack_name + path_len, alloc - path_len, ".pack");
 	if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
 		free(p);
 		return NULL;
@@ -1144,9 +1195,10 @@ struct packed_git *add_packed_git(const char *path, int path_len, int local)
 struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path)
 {
 	const char *path = sha1_pack_name(sha1);
-	struct packed_git *p = alloc_packed_git(strlen(path) + 1);
+	int alloc = strlen(path) + 1;
+	struct packed_git *p = alloc_packed_git(alloc);
 
-	strcpy(p->pack_name, path);
+	memcpy(p->pack_name, path, alloc); /* includes NUL */
 	hashcpy(p->sha1, sha1);
 	if (check_packed_git_idx(idx_path, p)) {
 		free(p);
@@ -1195,7 +1247,7 @@ static void report_pack_garbage(struct string_list *list)
 	if (!report_garbage)
 		return;
 
-	sort_string_list(list);
+	string_list_sort(list);
 
 	for (i = 0; i < list->nr; i++) {
 		const char *path = list->items[i].string;
@@ -1416,7 +1468,7 @@ int check_sha1_signature(const unsigned char *sha1, void *map,
 		return -1;
 
 	/* Generate the header */
-	hdrlen = sprintf(hdr, "%s %lu", typename(obj_type), size) + 1;
+	hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(obj_type), size) + 1;
 
 	/* Sha1.. */
 	git_SHA1_Init(&c);
@@ -1443,7 +1495,10 @@ int git_open_noatime(const char *name)
 	static int sha1_file_open_flag = O_NOATIME;
 
 	for (;;) {
-		int fd = open(name, O_RDONLY | sha1_file_open_flag);
+		int fd;
+
+		errno = 0;
+		fd = open(name, O_RDONLY | sha1_file_open_flag);
 		if (fd >= 0)
 			return fd;
 
@@ -1561,6 +1616,40 @@ int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long ma
 	return git_inflate(stream, 0);
 }
 
+static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map,
+					unsigned long mapsize, void *buffer,
+					unsigned long bufsiz, struct strbuf *header)
+{
+	int status;
+
+	status = unpack_sha1_header(stream, map, mapsize, buffer, bufsiz);
+
+	/*
+	 * Check if entire header is unpacked in the first iteration.
+	 */
+	if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
+		return 0;
+
+	/*
+	 * buffer[0..bufsiz] was not large enough.  Copy the partial
+	 * result out to header, and then append the result of further
+	 * reading the stream.
+	 */
+	strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
+	stream->next_out = buffer;
+	stream->avail_out = bufsiz;
+
+	do {
+		status = git_inflate(stream, 0);
+		strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
+		if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
+			return 0;
+		stream->next_out = buffer;
+		stream->avail_out = bufsiz;
+	} while (status != Z_STREAM_END);
+	return -1;
+}
+
 static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
 {
 	int bytes = strlen(buffer) + 1;
@@ -1611,27 +1700,38 @@ static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long s
  * too permissive for what we want to check. So do an anal
  * object header parse by hand.
  */
-int parse_sha1_header(const char *hdr, unsigned long *sizep)
+static int parse_sha1_header_extended(const char *hdr, struct object_info *oi,
+			       unsigned int flags)
 {
-	char type[10];
-	int i;
+	const char *type_buf = hdr;
 	unsigned long size;
+	int type, type_len = 0;
 
 	/*
-	 * The type can be at most ten bytes (including the
-	 * terminating '\0' that we add), and is followed by
+	 * The type can be of any size but is followed by
 	 * a space.
 	 */
-	i = 0;
 	for (;;) {
 		char c = *hdr++;
 		if (c == ' ')
 			break;
-		type[i++] = c;
-		if (i >= sizeof(type))
-			return -1;
+		type_len++;
 	}
-	type[i] = 0;
+
+	type = type_from_string_gently(type_buf, type_len, 1);
+	if (oi->typename)
+		strbuf_add(oi->typename, type_buf, type_len);
+	/*
+	 * Set type to 0 if its an unknown object and
+	 * we're obtaining the type using '--allow-unkown-type'
+	 * option.
+	 */
+	if ((flags & LOOKUP_UNKNOWN_OBJECT) && (type < 0))
+		type = 0;
+	else if (type < 0)
+		die("invalid object type");
+	if (oi->typep)
+		*oi->typep = type;
 
 	/*
 	 * The length must follow immediately, and be in canonical
@@ -1649,12 +1749,24 @@ int parse_sha1_header(const char *hdr, unsigned long *sizep)
 			size = size * 10 + c;
 		}
 	}
-	*sizep = size;
+
+	if (oi->sizep)
+		*oi->sizep = size;
 
 	/*
 	 * The length must be followed by a zero byte
 	 */
-	return *hdr ? -1 : type_from_string(type);
+	return *hdr ? -1 : type;
+}
+
+int parse_sha1_header(const char *hdr, unsigned long *sizep)
+{
+	struct object_info oi;
+
+	oi.sizep = sizep;
+	oi.typename = NULL;
+	oi.typep = NULL;
+	return parse_sha1_header_extended(hdr, &oi, LOOKUP_REPLACE_OBJECT);
 }
 
 static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
@@ -2470,10 +2582,8 @@ static int fill_pack_entry(const unsigned char *sha1,
 	 * answer, as it may have been deleted since the index was
 	 * loaded!
 	 */
-	if (!is_pack_valid(p)) {
-		warning("packfile %s cannot be accessed", p->pack_name);
+	if (!is_pack_valid(p))
 		return 0;
-	}
 	e->offset = offset;
 	e->p = p;
 	hashcpy(e->sha1, sha1);
@@ -2521,13 +2631,15 @@ struct packed_git *find_sha1_pack(const unsigned char *sha1,
 }
 
 static int sha1_loose_object_info(const unsigned char *sha1,
-				  struct object_info *oi)
+				  struct object_info *oi,
+				  int flags)
 {
-	int status;
-	unsigned long mapsize, size;
+	int status = 0;
+	unsigned long mapsize;
 	void *map;
 	git_zstream stream;
 	char hdr[32];
+	struct strbuf hdrbuf = STRBUF_INIT;
 
 	if (oi->delta_base_sha1)
 		hashclr(oi->delta_base_sha1);
@@ -2540,7 +2652,7 @@ static int sha1_loose_object_info(const unsigned char *sha1,
 	 * return value implicitly indicates whether the
 	 * object even exists.
 	 */
-	if (!oi->typep && !oi->sizep) {
+	if (!oi->typep && !oi->typename && !oi->sizep) {
 		struct stat st;
 		if (stat_sha1_file(sha1, &st) < 0)
 			return -1;
@@ -2554,17 +2666,26 @@ static int sha1_loose_object_info(const unsigned char *sha1,
 		return -1;
 	if (oi->disk_sizep)
 		*oi->disk_sizep = mapsize;
-	if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
+	if ((flags & LOOKUP_UNKNOWN_OBJECT)) {
+		if (unpack_sha1_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0)
+			status = error("unable to unpack %s header with --allow-unknown-type",
+				       sha1_to_hex(sha1));
+	} else if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
 		status = error("unable to unpack %s header",
 			       sha1_to_hex(sha1));
-	else if ((status = parse_sha1_header(hdr, &size)) < 0)
+	if (status < 0)
+		; /* Do nothing */
+	else if (hdrbuf.len) {
+		if ((status = parse_sha1_header_extended(hdrbuf.buf, oi, flags)) < 0)
+			status = error("unable to parse %s header with --allow-unknown-type",
+				       sha1_to_hex(sha1));
+	} else if ((status = parse_sha1_header_extended(hdr, oi, flags)) < 0)
 		status = error("unable to parse %s header", sha1_to_hex(sha1));
-	else if (oi->sizep)
-		*oi->sizep = size;
 	git_inflate_end(&stream);
 	munmap(map, mapsize);
-	if (oi->typep)
+	if (status && oi->typep)
 		*oi->typep = status;
+	strbuf_release(&hdrbuf);
 	return 0;
 }
 
@@ -2573,6 +2694,7 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 	struct cached_object *co;
 	struct pack_entry e;
 	int rtype;
+	enum object_type real_type;
 	const unsigned char *real = lookup_replace_object_extended(sha1, flags);
 
 	co = find_cached_object(real);
@@ -2585,13 +2707,15 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 			*(oi->disk_sizep) = 0;
 		if (oi->delta_base_sha1)
 			hashclr(oi->delta_base_sha1);
+		if (oi->typename)
+			strbuf_addstr(oi->typename, typename(co->type));
 		oi->whence = OI_CACHED;
 		return 0;
 	}
 
 	if (!find_pack_entry(real, &e)) {
 		/* Most likely it's a loose object. */
-		if (!sha1_loose_object_info(real, oi)) {
+		if (!sha1_loose_object_info(real, oi, flags)) {
 			oi->whence = OI_LOOSE;
 			return 0;
 		}
@@ -2602,9 +2726,18 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 			return -1;
 	}
 
+	/*
+	 * packed_object_info() does not follow the delta chain to
+	 * find out the real type, unless it is given oi->typep.
+	 */
+	if (oi->typename && !oi->typep)
+		oi->typep = &real_type;
+
 	rtype = packed_object_info(e.p, e.offset, oi);
 	if (rtype < 0) {
 		mark_bad_packed_object(e.p, real);
+		if (oi->typep == &real_type)
+			oi->typep = NULL;
 		return sha1_object_info_extended(real, oi, 0);
 	} else if (in_delta_base_cache(e.p, e.offset)) {
 		oi->whence = OI_DBCACHED;
@@ -2615,6 +2748,10 @@ int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi,
 		oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
 					 rtype == OBJ_OFS_DELTA);
 	}
+	if (oi->typename)
+		strbuf_addstr(oi->typename, typename(*oi->typep));
+	if (oi->typep == &real_type)
+		oi->typep = NULL;
 
 	return 0;
 }
@@ -2797,7 +2934,7 @@ static void write_sha1_file_prepare(const void *buf, unsigned long len,
 	git_SHA_CTX c;
 
 	/* Generate the header */
-	*hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
+	*hdrlen = xsnprintf(hdr, *hdrlen, "%s %lu", type, len)+1;
 
 	/* Sha1.. */
 	git_SHA1_Init(&c);
@@ -2808,11 +2945,8 @@ static void write_sha1_file_prepare(const void *buf, unsigned long len,
 
 /*
  * Move the just written object into its final resting place.
- * NEEDSWORK: this should be renamed to finalize_temp_file() as
- * "moving" is only a part of what it does, when no patch between
- * master to pu changes the call sites of this function.
  */
-int move_temp_to_file(const char *tmpfile, const char *filename)
+int finalize_object_file(const char *tmpfile, const char *filename)
 {
 	int ret = 0;
 
@@ -2863,7 +2997,7 @@ int hash_sha1_file(const void *buf, unsigned long len, const char *type,
                    unsigned char *sha1)
 {
 	char hdr[32];
-	int hdrlen;
+	int hdrlen = sizeof(hdr);
 	write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
 	return 0;
 }
@@ -2893,29 +3027,31 @@ static inline int directory_size(const char *filename)
  * We want to avoid cross-directory filename renames, because those
  * can have problems on various filesystems (FAT, NFS, Coda).
  */
-static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
+static int create_tmpfile(struct strbuf *tmp, const char *filename)
 {
 	int fd, dirlen = directory_size(filename);
 
-	if (dirlen + 20 > bufsiz) {
-		errno = ENAMETOOLONG;
-		return -1;
-	}
-	memcpy(buffer, filename, dirlen);
-	strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
-	fd = git_mkstemp_mode(buffer, 0444);
+	strbuf_reset(tmp);
+	strbuf_add(tmp, filename, dirlen);
+	strbuf_addstr(tmp, "tmp_obj_XXXXXX");
+	fd = git_mkstemp_mode(tmp->buf, 0444);
 	if (fd < 0 && dirlen && errno == ENOENT) {
-		/* Make sure the directory exists */
-		memcpy(buffer, filename, dirlen);
-		buffer[dirlen-1] = 0;
-		if (mkdir(buffer, 0777) && errno != EEXIST)
+		/*
+		 * Make sure the directory exists; note that the contents
+		 * of the buffer are undefined after mkstemp returns an
+		 * error, so we have to rewrite the whole buffer from
+		 * scratch.
+		 */
+		strbuf_reset(tmp);
+		strbuf_add(tmp, filename, dirlen - 1);
+		if (mkdir(tmp->buf, 0777) && errno != EEXIST)
 			return -1;
-		if (adjust_shared_perm(buffer))
+		if (adjust_shared_perm(tmp->buf))
 			return -1;
 
 		/* Try again */
-		strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
-		fd = git_mkstemp_mode(buffer, 0444);
+		strbuf_addstr(tmp, "/tmp_obj_XXXXXX");
+		fd = git_mkstemp_mode(tmp->buf, 0444);
 	}
 	return fd;
 }
@@ -2928,10 +3064,10 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 	git_zstream stream;
 	git_SHA_CTX c;
 	unsigned char parano_sha1[20];
-	static char tmp_file[PATH_MAX];
+	static struct strbuf tmp_file = STRBUF_INIT;
 	const char *filename = sha1_file_name(sha1);
 
-	fd = create_tmpfile(tmp_file, sizeof(tmp_file), filename);
+	fd = create_tmpfile(&tmp_file, filename);
 	if (fd < 0) {
 		if (errno == EACCES)
 			return error("insufficient permission for adding an object to repository database %s", get_object_directory());
@@ -2940,7 +3076,6 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 	}
 
 	/* Set it up */
-	memset(&stream, 0, sizeof(stream));
 	git_deflate_init(&stream, zlib_compression_level);
 	stream.next_out = compressed;
 	stream.avail_out = sizeof(compressed);
@@ -2981,12 +3116,12 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 		struct utimbuf utb;
 		utb.actime = mtime;
 		utb.modtime = mtime;
-		if (utime(tmp_file, &utb) < 0)
+		if (utime(tmp_file.buf, &utb) < 0)
 			warning("failed utime() on %s: %s",
-				tmp_file, strerror(errno));
+				tmp_file.buf, strerror(errno));
 	}
 
-	return move_temp_to_file(tmp_file, filename);
+	return finalize_object_file(tmp_file.buf, filename);
 }
 
 static int freshen_loose_object(const unsigned char *sha1)
@@ -2997,26 +3132,52 @@ static int freshen_loose_object(const unsigned char *sha1)
 static int freshen_packed_object(const unsigned char *sha1)
 {
 	struct pack_entry e;
-	return find_pack_entry(sha1, &e) && freshen_file(e.p->pack_name);
+	if (!find_pack_entry(sha1, &e))
+		return 0;
+	if (e.p->freshened)
+		return 1;
+	if (!freshen_file(e.p->pack_name))
+		return 0;
+	e.p->freshened = 1;
+	return 1;
 }
 
-int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
+int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *sha1)
 {
-	unsigned char sha1[20];
 	char hdr[32];
-	int hdrlen;
+	int hdrlen = sizeof(hdr);
 
 	/* Normally if we have it in the pack then we do not bother writing
 	 * it out into .git/objects/??/?{38} file.
 	 */
 	write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
-	if (returnsha1)
-		hashcpy(returnsha1, sha1);
-	if (freshen_loose_object(sha1) || freshen_packed_object(sha1))
+	if (freshen_packed_object(sha1) || freshen_loose_object(sha1))
 		return 0;
 	return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
 }
 
+int hash_sha1_file_literally(const void *buf, unsigned long len, const char *type,
+			     unsigned char *sha1, unsigned flags)
+{
+	char *header;
+	int hdrlen, status = 0;
+
+	/* type string, SP, %lu of the length plus NUL must fit this */
+	hdrlen = strlen(type) + 32;
+	header = xmalloc(hdrlen);
+	write_sha1_file_prepare(buf, len, type, sha1, header, &hdrlen);
+
+	if (!(flags & HASH_WRITE_OBJECT))
+		goto cleanup;
+	if (freshen_packed_object(sha1) || freshen_loose_object(sha1))
+		goto cleanup;
+	status = write_loose_object(sha1, header, hdrlen, buf, len, 0);
+
+cleanup:
+	free(header);
+	return status;
+}
+
 int force_object_loose(const unsigned char *sha1, time_t mtime)
 {
 	void *buf;
@@ -3031,7 +3192,7 @@ int force_object_loose(const unsigned char *sha1, time_t mtime)
 	buf = read_packed_sha1(sha1, &type, &len);
 	if (!buf)
 		return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
-	hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
+	hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), len) + 1;
 	ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
 	free(buf);
 
@@ -3052,7 +3213,7 @@ int has_sha1_pack(const unsigned char *sha1)
 	return find_pack_entry(sha1, &e);
 }
 
-int has_sha1_file(const unsigned char *sha1)
+int has_sha1_file_with_flags(const unsigned char *sha1, int flags)
 {
 	struct pack_entry e;
 
@@ -3060,6 +3221,8 @@ int has_sha1_file(const unsigned char *sha1)
 		return 1;
 	if (has_loose_object(sha1))
 		return 1;
+	if (flags & HAS_SHA1_QUICK)
+		return 0;
 	reprepare_packed_git();
 	return find_pack_entry(sha1, &e);
 }
@@ -3177,7 +3340,7 @@ static int index_core(unsigned char *sha1, int fd, size_t size,
 	int ret;
 
 	if (!size) {
-		ret = index_mem(sha1, NULL, size, type, path, flags);
+		ret = index_mem(sha1, "", size, type, path, flags);
 	} else if (size <= SMALL_FILE_SIZE) {
 		char *buf = xmalloc(size);
 		if (size == read_in_full(fd, buf, size))
@@ -3356,31 +3519,42 @@ static int for_each_file_in_obj_subdir(int subdir_nr,
 	return r;
 }
 
-int for_each_loose_file_in_objdir(const char *path,
+int for_each_loose_file_in_objdir_buf(struct strbuf *path,
 			    each_loose_object_fn obj_cb,
 			    each_loose_cruft_fn cruft_cb,
 			    each_loose_subdir_fn subdir_cb,
 			    void *data)
 {
-	struct strbuf buf = STRBUF_INIT;
-	size_t baselen;
+	size_t baselen = path->len;
 	int r = 0;
 	int i;
 
-	strbuf_addstr(&buf, path);
-	strbuf_addch(&buf, '/');
-	baselen = buf.len;
-
 	for (i = 0; i < 256; i++) {
-		strbuf_addf(&buf, "%02x", i);
-		r = for_each_file_in_obj_subdir(i, &buf, obj_cb, cruft_cb,
+		strbuf_addf(path, "/%02x", i);
+		r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
 						subdir_cb, data);
-		strbuf_setlen(&buf, baselen);
+		strbuf_setlen(path, baselen);
 		if (r)
 			break;
 	}
 
+	return r;
+}
+
+int for_each_loose_file_in_objdir(const char *path,
+				  each_loose_object_fn obj_cb,
+				  each_loose_cruft_fn cruft_cb,
+				  each_loose_subdir_fn subdir_cb,
+				  void *data)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int r;
+
+	strbuf_addstr(&buf, path);
+	r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb,
+					      subdir_cb, data);
 	strbuf_release(&buf);
+
 	return r;
 }
 
@@ -3393,12 +3567,19 @@ static int loose_from_alt_odb(struct alternate_object_database *alt,
 			      void *vdata)
 {
 	struct loose_alt_odb_data *data = vdata;
-	return for_each_loose_file_in_objdir(alt->base,
-					     data->cb, NULL, NULL,
-					     data->data);
+	struct strbuf buf = STRBUF_INIT;
+	int r;
+
+	/* copy base not including trailing '/' */
+	strbuf_add(&buf, alt->base, alt->name - alt->base - 1);
+	r = for_each_loose_file_in_objdir_buf(&buf,
+					      data->cb, NULL, NULL,
+					      data->data);
+	strbuf_release(&buf);
+	return r;
 }
 
-int for_each_loose_object(each_loose_object_fn cb, void *data)
+int for_each_loose_object(each_loose_object_fn cb, void *data, unsigned flags)
 {
 	struct loose_alt_odb_data alt;
 	int r;
@@ -3408,6 +3589,9 @@ int for_each_loose_object(each_loose_object_fn cb, void *data)
 	if (r)
 		return r;
 
+	if (flags & FOR_EACH_OBJECT_LOCAL_ONLY)
+		return 0;
+
 	alt.cb = cb;
 	alt.data = data;
 	return foreach_alt_odb(loose_from_alt_odb, &alt);
@@ -3432,16 +3616,23 @@ static int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn c
 	return r;
 }
 
-int for_each_packed_object(each_packed_object_fn cb, void *data)
+int for_each_packed_object(each_packed_object_fn cb, void *data, unsigned flags)
 {
 	struct packed_git *p;
 	int r = 0;
+	int pack_errors = 0;
 
 	prepare_packed_git();
 	for (p = packed_git; p; p = p->next) {
+		if ((flags & FOR_EACH_OBJECT_LOCAL_ONLY) && !p->pack_local)
+			continue;
+		if (open_pack_index(p)) {
+			pack_errors = 1;
+			continue;
+		}
 		r = for_each_object_in_pack(p, cb, data);
 		if (r)
 			break;
 	}
-	return r;
+	return r ? r : pack_errors;
 }