X-Git-Url: https://git.verplant.org/?a=blobdiff_plain;f=sha1_file.c;h=74dc2aab26c0e9f87e9238686ad0a077b1570d4a;hb=bbca20accefe8329f976371d0d8c111c965cdf1a;hp=737ecb48002c873d43bafc99810feb00194b0d8c;hpb=dcde55bc58ae845307efbdce3a1071f75ccd758e;p=git.git

diff --git a/sha1_file.c b/sha1_file.c
index 737ecb48..74dc2aab 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -102,9 +102,30 @@ char *get_index_file(void)
 	return git_index_file;
 }
 
-int get_sha1(const char *str, unsigned char *sha1)
+char *git_path(const char *fmt, ...)
 {
 	static char pathname[PATH_MAX];
+	va_list args;
+	int len;
+
+	if (!git_dir)
+		setup_git_env();
+	len = strlen(git_dir);
+	if (len == 1 && *git_dir == '.')
+		len = 0;
+	if (len > PATH_MAX-100)
+		return "pad-path";
+	memcpy(pathname, git_dir, len);
+	if (len && git_dir[len-1] != '/')
+		pathname[len++] = '/';
+	va_start(args, fmt);
+	vsnprintf(pathname + len, sizeof(pathname) - len, fmt, args);
+	va_end(args);
+	return pathname;
+}
+
+int get_sha1(const char *str, unsigned char *sha1)
+{
 	static const char *prefix[] = {
 		"",
 		"refs",
@@ -118,11 +139,8 @@ int get_sha1(const char *str, unsigned char *sha1)
 	if (!get_sha1_hex(str, sha1))
 		return 0;
 
-	if (!git_dir)
-		setup_git_env();
 	for (p = prefix; *p; p++) {
-		snprintf(pathname, sizeof(pathname), "%s/%s/%s",
-			 git_dir, *p, str);
+		char * pathname = git_path("%s/%s", *p, str);
 		if (!get_sha1_file(pathname, sha1))
 			return 0;
 	}
@@ -272,12 +290,6 @@ static int pack_used_ctr;
 static unsigned long pack_mapped;
 struct packed_git *packed_git;
 
-struct pack_entry {
-	unsigned int offset;
-	unsigned char sha1[20];
-	struct packed_git *p;
-};
-
 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
 				void **idx_map_)
 {
@@ -300,9 +312,11 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
 		return -1;
 
 	index = idx_map;
+	*idx_map_ = idx_map;
+	*idx_size_ = idx_size;
 
 	/* check index map */
-	if (idx_size < 4*256 + 20)
+	if (idx_size < 4*256 + 20 + 20)
 		return error("index file too small");
 	nr = 0;
 	for (i = 0; i < 256; i++) {
@@ -322,17 +336,32 @@ static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
 	if (idx_size != 4*256 + nr * 24 + 20 + 20)
 		return error("wrong index file size");
 
-	*idx_map_ = idx_map;
-	*idx_size_ = idx_size;
 	return 0;
 }
 
-static void unuse_one_packed_git(void)
+static int unuse_one_packed_git(void)
 {
-	/* NOTYET */
+	struct packed_git *p, *lru = NULL;
+
+	for (p = packed_git; p; p = p->next) {
+		if (p->pack_use_cnt || !p->pack_base)
+			continue;
+		if (!lru || p->pack_last_used < lru->pack_last_used)
+			lru = p;
+	}
+	if (!lru)
+		return 0;
+	munmap(lru->pack_base, lru->pack_size);
+	lru->pack_base = NULL;
+	return 1;
+}
+
+void unuse_packed_git(struct packed_git *p)
+{
+	p->pack_use_cnt--;
 }
 
-static int use_packed_git(struct packed_git *p)
+int use_packed_git(struct packed_git *p)
 {
 	if (!p->pack_base) {
 		int fd;
@@ -340,28 +369,36 @@ static int use_packed_git(struct packed_git *p)
 		void *map;
 
 		pack_mapped += p->pack_size;
-		while (PACK_MAX_SZ < pack_mapped)
-			unuse_one_packed_git();
+		while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
+			; /* nothing */
 		fd = open(p->pack_name, O_RDONLY);
 		if (fd < 0)
-			return -1;
+			die("packfile %s cannot be opened", p->pack_name);
 		if (fstat(fd, &st)) {
 			close(fd);
-			return -1;
+			die("packfile %s cannot be opened", p->pack_name);
 		}
 		if (st.st_size != p->pack_size)
-			return -1;
+			die("packfile %s size mismatch.", p->pack_name);
 		map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
 		close(fd);
 		if (map == MAP_FAILED)
-			return -1;
+			die("packfile %s cannot be mapped.", p->pack_name);
 		p->pack_base = map;
+
+		/* Check if the pack file matches with the index file.
+		 * this is cheap.
+		 */
+		if (memcmp((char*)(p->index_base) + p->index_size - 40,
+			   p->pack_base + p->pack_size - 20, 20))
+			die("packfile %s does not match index.", p->pack_name);
 	}
 	p->pack_last_used = pack_used_ctr++;
+	p->pack_use_cnt++;
 	return 0;
 }
 
-static struct packed_git *add_packed_git(char *path, int path_len)
+struct packed_git *add_packed_git(char *path, int path_len)
 {
 	struct stat st;
 	struct packed_git *p;
@@ -388,6 +425,7 @@ static struct packed_git *add_packed_git(char *path, int path_len)
 	p->next = NULL;
 	p->pack_base = NULL;
 	p->pack_last_used = 0;
+	p->pack_use_cnt = 0;
 	return p;
 }
 
@@ -511,7 +549,7 @@ int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void
 	return inflate(stream, 0);
 }
 
-void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
+static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
 {
 	int bytes = strlen(buffer) + 1;
 	unsigned char *buf = xmalloc(1+size);
@@ -592,50 +630,67 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
 	return unpack_sha1_rest(&stream, hdr, *size);
 }
 
+/* forward declaration for a mutually recursive function */
+static int packed_object_info(struct pack_entry *entry,
+			      char *type, unsigned long *sizep);
+
 static int packed_delta_info(unsigned char *base_sha1,
 			     unsigned long delta_size,
 			     unsigned long left,
 			     char *type,
-			     unsigned long *sizep)
+			     unsigned long *sizep,
+			     struct packed_git *p)
 {
-	unsigned char *data;
-	unsigned char delta_head[64];
-	unsigned long data_size, result_size, base_size, verify_base_size;
-	z_stream stream;
-	int st;
+	struct pack_entry base_ent;
 
 	if (left < 20)
 		die("truncated pack file");
-	if (sha1_object_info(base_sha1, type, &base_size))
-		die("cannot get info for delta-pack base");
-
-	data = base_sha1 + 20;
-	data_size = left - 20;
 
-	memset(&stream, 0, sizeof(stream));
+	/* The base entry _must_ be in the same pack */
+	if (!find_pack_entry_one(base_sha1, &base_ent, p))
+		die("failed to find delta-pack base object %s",
+		    sha1_to_hex(base_sha1));
 
-	stream.next_in = data;
-	stream.avail_in = data_size;
-	stream.next_out = delta_head;
-	stream.avail_out = sizeof(delta_head);
+	/* We choose to only get the type of the base object and
+	 * ignore potentially corrupt pack file that expects the delta
+	 * based on a base with a wrong size.  This saves tons of
+	 * inflate() calls.
+	 */
 
-	inflateInit(&stream);
-	st = inflate(&stream, Z_FINISH);
-	inflateEnd(&stream);
-	if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head))
-		die("delta data unpack-initial failed");
+	if (packed_object_info(&base_ent, type, NULL))
+		die("cannot get info for delta-pack base");
 
-	/* Examine the initial part of the delta to figure out
-	 * the result size.  Verify the base size while we are at it.
-	 */
-	data = delta_head;
-	verify_base_size = get_delta_hdr_size(&data);
-	if (verify_base_size != base_size)
-		die("delta base size mismatch");
+	if (sizep) {
+		const unsigned char *data;
+		unsigned char delta_head[64];
+		unsigned long result_size;
+		z_stream stream;
+		int st;
+
+		memset(&stream, 0, sizeof(stream));
+
+		data = stream.next_in = base_sha1 + 20;
+		stream.avail_in = left - 20;
+		stream.next_out = delta_head;
+		stream.avail_out = sizeof(delta_head);
+
+		inflateInit(&stream);
+		st = inflate(&stream, Z_FINISH);
+		inflateEnd(&stream);
+		if ((st != Z_STREAM_END) &&
+		    stream.total_out != sizeof(delta_head))
+			die("delta data unpack-initial failed");
+
+		/* Examine the initial part of the delta to figure out
+		 * the result size.
+		 */
+		data = delta_head;
+		get_delta_hdr_size(&data); /* ignore base size */
 
-	/* Read the result size */
-	result_size = get_delta_hdr_size(&data);
-	*sizep = result_size;
+		/* Read the result size */
+		result_size = get_delta_hdr_size(&data);
+		*sizep = result_size;
+	}
 	return 0;
 }
 
@@ -667,6 +722,57 @@ static unsigned long unpack_object_header(struct packed_git *p, unsigned long of
 	return offset;
 }
 
+void packed_object_info_detail(struct pack_entry *e,
+			       char *type,
+			       unsigned long *size,
+			       unsigned long *store_size,
+			       int *delta_chain_length,
+			       unsigned char *base_sha1)
+{
+	struct packed_git *p = e->p;
+	unsigned long offset, left;
+	unsigned char *pack;
+	enum object_type kind;
+
+	offset = unpack_object_header(p, e->offset, &kind, size);
+	pack = p->pack_base + offset;
+	left = p->pack_size - offset;
+	if (kind != OBJ_DELTA)
+		*delta_chain_length = 0;
+	else {
+		int chain_length = 0;
+		memcpy(base_sha1, pack, 20);
+		do {
+			struct pack_entry base_ent;
+			unsigned long junk;
+
+			find_pack_entry_one(pack, &base_ent, p);
+			offset = unpack_object_header(p, base_ent.offset,
+						      &kind, &junk);
+			pack = p->pack_base + offset;
+			chain_length++;
+		} while (kind == OBJ_DELTA);
+		*delta_chain_length = chain_length;
+	}
+	switch (kind) {
+	case OBJ_COMMIT:
+		strcpy(type, "commit");
+		break;
+	case OBJ_TREE:
+		strcpy(type, "tree");
+		break;
+	case OBJ_BLOB:
+		strcpy(type, "blob");
+		break;
+	case OBJ_TAG:
+		strcpy(type, "tag");
+		break;
+	default:
+		die("corrupted pack file");
+	}
+	*store_size = 0; /* notyet */
+}
+
 static int packed_object_info(struct pack_entry *entry,
 			      char *type, unsigned long *sizep)
 {
@@ -674,6 +780,7 @@ static int packed_object_info(struct pack_entry *entry,
 	unsigned long offset, size, left;
 	unsigned char *pack;
 	enum object_type kind;
+	int retval;
 
 	if (use_packed_git(p))
 		die("cannot map packed file");
@@ -684,8 +791,9 @@ static int packed_object_info(struct pack_entry *entry,
 
 	switch (kind) {
 	case OBJ_DELTA:
-		return packed_delta_info(pack, size, left, type, sizep);
-		break;
+		retval = packed_delta_info(pack, size, left, type, sizep, p);
+		unuse_packed_git(p);
+		return retval;
 	case OBJ_COMMIT:
 		strcpy(type, "commit");
 		break;
@@ -701,7 +809,9 @@ static int packed_object_info(struct pack_entry *entry,
 	default:
 		die("corrupted pack file");
 	}
-	*sizep = size;
+	if (sizep)
+		*sizep = size;
+	unuse_packed_git(p);
 	return 0;
 }
 
@@ -712,8 +822,10 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
 				unsigned long delta_size,
 				unsigned long left,
 				char *type,
-				unsigned long *sizep)
+				unsigned long *sizep,
+				struct packed_git *p)
 {
+	struct pack_entry base_ent;
 	void *data, *delta_data, *result, *base;
 	unsigned long data_size, result_size, base_size;
 	z_stream stream;
@@ -738,8 +850,11 @@ static void *unpack_delta_entry(unsigned char *base_sha1,
 	if ((st != Z_STREAM_END) || stream.total_out != delta_size)
 		die("delta data unpack failed");
 
-	/* This may recursively unpack the base, which is what we want */
-	base = read_sha1_file(base_sha1, type, &base_size);
+	/* The base entry _must_ be in the same pack */
+	if (!find_pack_entry_one(base_sha1, &base_ent, p))
+		die("failed to find delta-pack base object %s",
+		    sha1_to_hex(base_sha1));
+	base = unpack_entry_gently(&base_ent, type, &base_size);
 	if (!base)
 		die("failed to read delta-pack base object %s",
 		    sha1_to_hex(base_sha1));
@@ -760,7 +875,7 @@ static void *unpack_non_delta_entry(unsigned char *data,
 {
 	int st;
 	z_stream stream;
-	char *buffer;
+	unsigned char *buffer;
 
 	buffer = xmalloc(size + 1);
 	buffer[size] = 0;
@@ -785,19 +900,34 @@ static void *unpack_entry(struct pack_entry *entry,
 			  char *type, unsigned long *sizep)
 {
 	struct packed_git *p = entry->p;
-	unsigned long offset, size, left;
-	unsigned char *pack;
-	enum object_type kind;
+	void *retval;
 
 	if (use_packed_git(p))
 		die("cannot map packed file");
+	retval = unpack_entry_gently(entry, type, sizep);
+	unuse_packed_git(p);
+	if (!retval)
+		die("corrupted pack file");
+	return retval;
+}
+
+/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
+void *unpack_entry_gently(struct pack_entry *entry,
+			  char *type, unsigned long *sizep)
+{
+	struct packed_git *p = entry->p;
+	unsigned long offset, size, left;
+	unsigned char *pack;
+	enum object_type kind;
+	void *retval;
 
 	offset = unpack_object_header(p, entry->offset, &kind, &size);
 	pack = p->pack_base + offset;
 	left = p->pack_size - offset;
 	switch (kind) {
 	case OBJ_DELTA:
-		return unpack_delta_entry(pack, size, left, type, sizep);
+		retval = unpack_delta_entry(pack, size, left, type, sizep, p);
+		return retval;
 	case OBJ_COMMIT:
 		strcpy(type, "commit");
 		break;
@@ -811,15 +941,16 @@ static void *unpack_entry(struct pack_entry *entry,
 		strcpy(type, "tag");
 		break;
 	default:
-		die("corrupted pack file");
+		return NULL;
 	}
 	*sizep = size;
-	return unpack_non_delta_entry(pack, size, left);
+	retval = unpack_non_delta_entry(pack, size, left);
+	return retval;
 }
 
 int num_packed_objects(const struct packed_git *p)
 {
-	/* See check_packed_git_idx and pack-objects.c */
+	/* See check_packed_git_idx() */
 	return (p->index_size - 20 - 20 - 4*256) / 24;
 }
 
@@ -833,10 +964,10 @@ int nth_packed_object_sha1(const struct packed_git *p, int n,
 	return 0;
 }
 
-static int find_pack_entry_1(const unsigned char *sha1,
-			     struct pack_entry *e, struct packed_git *p)
+int find_pack_entry_one(const unsigned char *sha1,
+			struct pack_entry *e, struct packed_git *p)
 {
-	int *level1_ofs = p->index_base;
+	unsigned int *level1_ofs = p->index_base;
 	int hi = ntohl(level1_ofs[*sha1]);
 	int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
 	void *index = p->index_base + 256;
@@ -864,7 +995,7 @@ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
 	prepare_packed_git();
 
 	for (p = packed_git; p; p = p->next) {
-		if (find_pack_entry_1(sha1, e, p))
+		if (find_pack_entry_one(sha1, e, p))
 			return 1;
 	}
 	return 0;
@@ -884,12 +1015,7 @@ int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep
 
 		if (!find_pack_entry(sha1, &e))
 			return error("unable to find %s", sha1_to_hex(sha1));
-		if (!packed_object_info(&e, type, sizep))
-			return 0;
-		/* sheesh */
-		map = unpack_entry(&e, type, sizep);
-		free(map);
-		return (map == NULL) ? 0 : -1;
+		return packed_object_info(&e, type, sizep);
 	}
 	if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
 		status = error("unable to unpack %s header",
@@ -898,7 +1024,8 @@ int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep
 		status = error("unable to parse %s header", sha1_to_hex(sha1));
 	else {
 		status = 0;
-		*sizep = size;
+		if (sizep)
+			*sizep = size;
 	}
 	inflateEnd(&stream);
 	munmap(map, mapsize);
@@ -1158,6 +1285,12 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd)
 	return 0;
 }
 
+int has_sha1_pack(const unsigned char *sha1)
+{
+	struct pack_entry e;
+	return find_pack_entry(sha1, &e);
+}
+
 int has_sha1_file(const unsigned char *sha1)
 {
 	struct stat st;