From: Junio C Hamano <gitster@pobox.com>
Date: Mon, 17 Apr 2017 06:29:30 +0000 (-0700)
Subject: Merge branch 'jk/loose-object-info-report-error'
X-Git-Tag: v2.13.0-rc0~25
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/dfe46c5ce6e68d682f80f9874f0eb107e9fee797?hp=-c

Merge branch 'jk/loose-object-info-report-error'

Update error handling for codepath that deals with corrupt loose
objects.

* jk/loose-object-info-report-error:
index-pack: detect local corruption in collision check
sha1_loose_object_info: return error for corrupted objects
---

dfe46c5ce6e68d682f80f9874f0eb107e9fee797
diff --combined builtin/index-pack.c
index 197c51912d,9f17adb37b..4ff567db47
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@@ -307,15 -307,14 +307,15 @@@ static const char *open_pack_file(cons
  	if (from_stdin) {
  		input_fd = 0;
  		if (!pack_name) {
 -			static char tmp_file[PATH_MAX];
 -			output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
 +			struct strbuf tmp_file = STRBUF_INIT;
 +			output_fd = odb_mkstemp(&tmp_file,
  						"pack/tmp_pack_XXXXXX");
 -			pack_name = xstrdup(tmp_file);
 -		} else
 +			pack_name = strbuf_detach(&tmp_file, NULL);
 +		} else {
  			output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
 -		if (output_fd < 0)
 -			die_errno(_("unable to create '%s'"), pack_name);
 +			if (output_fd < 0)
 +				die_errno(_("unable to create '%s'"), pack_name);
 +		}
  		nothread_data.pack_fd = output_fd;
  	} else {
  		input_fd = open(pack_name, O_RDONLY);
@@@ -810,6 -809,8 +810,8 @@@ static void sha1_object(const void *dat
  		unsigned long has_size;
  		read_lock();
  		has_type = sha1_object_info(sha1, &has_size);
+ 		if (has_type < 0)
+ 			die(_("cannot read existing object info %s"), sha1_to_hex(sha1));
  		if (has_type != type || has_size != size)
  			die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
  		has_data = read_sha1_file(sha1, &has_type, &has_size);
@@@ -1443,11 -1444,10 +1445,11 @@@ static void final(const char *final_pac
  	if (!from_stdin) {
  		printf("%s\n", sha1_to_hex(sha1));
  	} else {
 -		char buf[48];
 -		int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
 -				   report, sha1_to_hex(sha1));
 -		write_or_die(1, buf, len);
 +		struct strbuf buf = STRBUF_INIT;
 +
 +		strbuf_addf(&buf, "%s\t%s\n", report, sha1_to_hex(sha1));
 +		write_or_die(1, buf.buf, buf.len);
 +		strbuf_release(&buf);
  
  		/*
  		 * Let's just mimic git-unpack-objects here and write
diff --combined sha1_file.c
index 43990dec73,b8fbcc54c5..7369f7495a
--- a/sha1_file.c
+++ b/sha1_file.c
@@@ -129,10 -129,8 +129,10 @@@ enum scld_error safe_create_leading_dir
  		*slash = '\0';
  		if (!stat(path, &st)) {
  			/* path exists */
 -			if (!S_ISDIR(st.st_mode))
 +			if (!S_ISDIR(st.st_mode)) {
 +				errno = ENOTDIR;
  				ret = SCLD_EXISTS;
 +			}
  		} else if (mkdir(path, 0777)) {
  			if (errno == EEXIST &&
  			    !stat(path, &st) && S_ISDIR(st.st_mode))
@@@ -160,85 -158,13 +160,85 @@@
  
  enum scld_error safe_create_leading_directories_const(const char *path)
  {
 +	int save_errno;
  	/* path points to cache entries, so xstrdup before messing with it */
  	char *buf = xstrdup(path);
  	enum scld_error result = safe_create_leading_directories(buf);
 +
 +	save_errno = errno;
  	free(buf);
 +	errno = save_errno;
  	return result;
  }
  
 +int raceproof_create_file(const char *path, create_file_fn fn, void *cb)
 +{
 +	/*
 +	 * The number of times we will try to remove empty directories
 +	 * in the way of path. This is only 1 because if another
 +	 * process is racily creating directories that conflict with
 +	 * us, we don't want to fight against them.
 +	 */
 +	int remove_directories_remaining = 1;
 +
 +	/*
 +	 * The number of times that we will try to create the
 +	 * directories containing path. We are willing to attempt this
 +	 * more than once, because another process could be trying to
 +	 * clean up empty directories at the same time as we are
 +	 * trying to create them.
 +	 */
 +	int create_directories_remaining = 3;
 +
 +	/* A scratch copy of path, filled lazily if we need it: */
 +	struct strbuf path_copy = STRBUF_INIT;
 +
 +	int ret, save_errno;
 +
 +	/* Sanity check: */
 +	assert(*path);
 +
 +retry_fn:
 +	ret = fn(path, cb);
 +	save_errno = errno;
 +	if (!ret)
 +		goto out;
 +
 +	if (errno == EISDIR && remove_directories_remaining-- > 0) {
 +		/*
 +		 * A directory is in the way. Maybe it is empty; try
 +		 * to remove it:
 +		 */
 +		if (!path_copy.len)
 +			strbuf_addstr(&path_copy, path);
 +
 +		if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY))
 +			goto retry_fn;
 +	} else if (errno == ENOENT && create_directories_remaining-- > 0) {
 +		/*
 +		 * Maybe the containing directory didn't exist, or
 +		 * maybe it was just deleted by a process that is
 +		 * racing with us to clean up empty directories. Try
 +		 * to create it:
 +		 */
 +		enum scld_error scld_result;
 +
 +		if (!path_copy.len)
 +			strbuf_addstr(&path_copy, path);
 +
 +		do {
 +			scld_result = safe_create_leading_directories(path_copy.buf);
 +			if (scld_result == SCLD_OK)
 +				goto retry_fn;
 +		} while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
 +	}
 +
 +out:
 +	strbuf_release(&path_copy);
 +	errno = save_errno;
 +	return ret;
 +}
 +
  static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
  {
  	int i;
@@@ -662,7 -588,7 +662,7 @@@ static int freshen_file(const char *fn
   * 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)
 +int check_and_freshen_file(const char *fn, int freshen)
  {
  	if (access(fn, F_OK))
  		return 0;
@@@ -2701,17 -2627,6 +2701,17 @@@ const unsigned char *nth_packed_object_
  	}
  }
  
 +const struct object_id *nth_packed_object_oid(struct object_id *oid,
 +					      struct packed_git *p,
 +					      uint32_t n)
 +{
 +	const unsigned char *hash = nth_packed_object_sha1(p, n);
 +	if (!hash)
 +		return NULL;
 +	hashcpy(oid->hash, hash);
 +	return oid;
 +}
 +
  void check_pack_index_ptr(const struct packed_git *p, const void *vptr)
  {
  	const unsigned char *ptr = vptr;
@@@ -2952,7 -2867,7 +2952,7 @@@ static int sha1_loose_object_info(cons
  	if (status && oi->typep)
  		*oi->typep = status;
  	strbuf_release(&hdrbuf);
- 	return 0;
+ 	return (status < 0) ? status : 0;
  }
  
  int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags)
@@@ -3758,15 -3673,15 +3758,15 @@@ static int for_each_file_in_obj_subdir(
  		strbuf_setlen(path, baselen);
  		strbuf_addf(path, "/%s", de->d_name);
  
 -		if (strlen(de->d_name) == 38)  {
 -			char hex[41];
 -			unsigned char sha1[20];
 +		if (strlen(de->d_name) == GIT_SHA1_HEXSZ - 2)  {
 +			char hex[GIT_SHA1_HEXSZ+1];
 +			struct object_id oid;
  
 -			snprintf(hex, sizeof(hex), "%02x%s",
 -				 subdir_nr, de->d_name);
 -			if (!get_sha1_hex(hex, sha1)) {
 +			xsnprintf(hex, sizeof(hex), "%02x%s",
 +				  subdir_nr, de->d_name);
 +			if (!get_oid_hex(hex, &oid)) {
  				if (obj_cb) {
 -					r = obj_cb(sha1, path->buf, data);
 +					r = obj_cb(&oid, path->buf, data);
  					if (r)
  						break;
  				}
@@@ -3872,13 -3787,13 +3872,13 @@@ static int for_each_object_in_pack(stru
  	int r = 0;
  
  	for (i = 0; i < p->num_objects; i++) {
 -		const unsigned char *sha1 = nth_packed_object_sha1(p, i);
 +		struct object_id oid;
  
 -		if (!sha1)
 +		if (!nth_packed_object_oid(&oid, p, i))
  			return error("unable to get sha1 of object %u in %s",
  				     i, p->pack_name);
  
 -		r = cb(sha1, p, i, data);
 +		r = cb(&oid, p, i, data);
  		if (r)
  			break;
  	}