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[PATCH 2/8] Rename resolve_ref() to resolve_ref_unsafe()

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Nov 17, 2011, 09:32 UTC
Message-ID
<1321522335-24193-3-git-send-email-pclouds@gmail.com>
In-Reply-To
<1321522335-24193-1-git-send-email-pclouds@gmail.com>

resolve_ref() may return a pointer to a shared buffer and can be overwritten by the next resolve_ref() calls. Callers need to pay attention, not to keep the pointer when the next call happens.

Rename with "_unsafe" suffix to warn developers (or reviewers) before introducing new call sites.

This patch is generated using this command
git grep -l 'resolve_ref(' -- '*.[ch]'|xargs sed -i 's/resolve_ref(/resolve_ref_unsafe(/g'
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 branch.c                |    2 +-
 builtin/branch.c        |    6 +++---
 builtin/checkout.c      |    2 +-
 builtin/commit.c        |    2 +-
 builtin/fmt-merge-msg.c |    2 +-
 builtin/for-each-ref.c  |    2 +-
 builtin/fsck.c          |    2 +-
 builtin/merge.c         |    2 +-
 builtin/notes.c         |    2 +-
 builtin/receive-pack.c  |    4 ++--
 builtin/remote.c        |    2 +-
 builtin/show-branch.c   |    4 ++--
 builtin/symbolic-ref.c  |    2 +-
 cache.h                 |    2 +-
 reflog-walk.c           |    4 ++--
 refs.c                  |   20 ++++++++++----------
 remote.c                |    6 +++---
 transport.c             |    2 +-
 wt-status.c             |    2 +-
 19 files changed, 35 insertions(+), 35 deletions(-)
diff --git a/branch.c b/branch.c
index d809876..243355b 100644
--- a/branch.c
+++ b/branch.c
@@ -151,7 +151,7 @@ int validate_new_branchname(const char *name, struct strbuf *ref,
 		const char *head;
 		unsigned char sha1[20];
 
-		head = resolve_ref("HEAD", sha1, 0, NULL);
+		head = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
 		if (!is_bare_repository() && head && !strcmp(head, ref->buf))
 			die("Cannot force update the current branch.");
 	}
diff --git a/builtin/branch.c b/builtin/branch.c
index 0fe9c4d..6903b0d 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -115,7 +115,7 @@ static int branch_merged(int kind, const char *name,
 		    branch->merge[0] &&
 		    branch->merge[0]->dst &&
 		    (reference_name =
-		     resolve_ref(branch->merge[0]->dst, sha1, 1, NULL)) != NULL)
+		     resolve_ref_unsafe(branch->merge[0]->dst, sha1, 1, NULL)) != NULL)
 			reference_rev = lookup_commit_reference(sha1);
 	}
 	if (!reference_rev)
@@ -250,7 +250,7 @@ static char *resolve_symref(const char *src, const char *prefix)
 	int flag;
 	const char *dst, *cp;
 
-	dst = resolve_ref(src, sha1, 0, &flag);
+	dst = resolve_ref_unsafe(src, sha1, 0, &flag);
 	if (!(dst && (flag & REF_ISSYMREF)))
 		return NULL;
 	if (prefix && (cp = skip_prefix(dst, prefix)))
@@ -688,7 +688,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 
 	track = git_branch_track;
 
-	head = resolve_ref("HEAD", head_sha1, 0, NULL);
+	head = resolve_ref_unsafe("HEAD", head_sha1, 0, NULL);
 	if (!head)
 		die(_("Failed to resolve HEAD as a valid ref."));
 	head = xstrdup(head);
diff --git a/builtin/checkout.c b/builtin/checkout.c
index beeaee4..2b8e73b 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -699,7 +699,7 @@ static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
 	unsigned char rev[20];
 	int flag;
 	memset(&old, 0, sizeof(old));
-	old.path = xstrdup(resolve_ref("HEAD", rev, 0, &flag));
+	old.path = xstrdup(resolve_ref_unsafe("HEAD", rev, 0, &flag));
 	old.commit = lookup_commit_reference_gently(rev, 1);
 	if (!(flag & REF_ISSYMREF)) {
 		free((char *)old.path);
diff --git a/builtin/commit.c b/builtin/commit.c
index c46f2d1..0be3b45 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1259,7 +1259,7 @@ static void print_summary(const char *prefix, const unsigned char *sha1,
 	struct commit *commit;
 	struct strbuf format = STRBUF_INIT;
 	unsigned char junk_sha1[20];
-	const char *head = resolve_ref("HEAD", junk_sha1, 0, NULL);
+	const char *head = resolve_ref_unsafe("HEAD", junk_sha1, 0, NULL);
 	struct pretty_print_context pctx = {0};
 	struct strbuf author_ident = STRBUF_INIT;
 	struct strbuf committer_ident = STRBUF_INIT;
diff --git a/builtin/fmt-merge-msg.c b/builtin/fmt-merge-msg.c
index 7e2f225..5c9b40e 100644
--- a/builtin/fmt-merge-msg.c
+++ b/builtin/fmt-merge-msg.c
@@ -263,7 +263,7 @@ static int do_fmt_merge_msg(int merge_title, struct strbuf *in,
 	const char *current_branch;
 
 	/* get current branch */
-	current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
+	current_branch = resolve_ref_unsafe("HEAD", head_sha1, 1, NULL);
 	if (!current_branch)
 		die("No current branch");
 	if (!prefixcmp(current_branch, "refs/heads/"))
diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index d90e5d2..b954ca8 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@@ -629,7 +629,7 @@ static void populate_value(struct refinfo *ref)
 	if (need_symref && (ref->flag & REF_ISSYMREF) && !ref->symref) {
 		unsigned char unused1[20];
 		const char *symref;
-		symref = resolve_ref(ref->refname, unused1, 1, NULL);
+		symref = resolve_ref_unsafe(ref->refname, unused1, 1, NULL);
 		if (symref)
 			ref->symref = xstrdup(symref);
 		else
diff --git a/builtin/fsck.c b/builtin/fsck.c
index df1a88b..0e0e17a 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -532,7 +532,7 @@ static int fsck_head_link(void)
 	if (verbose)
 		fprintf(stderr, "Checking HEAD link\n");
 
-	head_points_at = resolve_ref("HEAD", head_sha1, 0, &flag);
+	head_points_at = resolve_ref_unsafe("HEAD", head_sha1, 0, &flag);
 	if (!head_points_at)
 		return error("Invalid HEAD");
 	if (!strcmp(head_points_at, "HEAD"))
diff --git a/builtin/merge.c b/builtin/merge.c
index 42b4f9e..519e3c5 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -1095,7 +1095,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 	 * Check if we are _not_ on a detached HEAD, i.e. if there is a
 	 * current branch.
 	 */
-	branch = resolve_ref("HEAD", head_sha1, 0, &flag);
+	branch = resolve_ref_unsafe("HEAD", head_sha1, 0, &flag);
 	if (branch && !prefixcmp(branch, "refs/heads/"))
 		branch += 11;
 	if (!branch || is_null_sha1(head_sha1))
diff --git a/builtin/notes.c b/builtin/notes.c
index f8e437d..e191ce6 100644
--- a/builtin/notes.c
+++ b/builtin/notes.c
@@ -825,7 +825,7 @@ static int merge_commit(struct notes_merge_options *o)
 	t = xcalloc(1, sizeof(struct notes_tree));
 	init_notes(t, "NOTES_MERGE_PARTIAL", combine_notes_overwrite, 0);
 
-	o->local_ref = resolve_ref("NOTES_MERGE_REF", sha1, 0, NULL);
+	o->local_ref = resolve_ref_unsafe("NOTES_MERGE_REF", sha1, 0, NULL);
 	if (!o->local_ref)
 		die("Failed to resolve NOTES_MERGE_REF");
 
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 7ec68a1..333f2b0 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -571,7 +571,7 @@ static void check_aliased_update(struct command *cmd, struct string_list *list)
 	int flag;
 
 	strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
-	dst_name = resolve_ref(buf.buf, sha1, 0, &flag);
+	dst_name = resolve_ref_unsafe(buf.buf, sha1, 0, &flag);
 	strbuf_release(&buf);
 
 	if (!(flag & REF_ISSYMREF))
@@ -695,7 +695,7 @@ static void execute_commands(struct command *commands, const char *unpacker_erro
 
 	check_aliased_updates(commands);
 
-	head_name = resolve_ref("HEAD", sha1, 0, NULL);
+	head_name = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
 
 	for (cmd = commands; cmd; cmd = cmd->next)
 		if (!cmd->skip_update)
diff --git a/builtin/remote.c b/builtin/remote.c
index 407abfb..583eec9 100644
--- a/builtin/remote.c
+++ b/builtin/remote.c
@@ -573,7 +573,7 @@ static int read_remote_branches(const char *refname,
 	strbuf_addf(&buf, "refs/remotes/%s/", rename->old);
 	if (!prefixcmp(refname, buf.buf)) {
 		item = string_list_append(rename->remote_branches, xstrdup(refname));
-		symref = resolve_ref(refname, orig_sha1, 1, &flag);
+		symref = resolve_ref_unsafe(refname, orig_sha1, 1, &flag);
 		if (flag & REF_ISSYMREF)
 			item->util = xstrdup(symref);
 		else
diff --git a/builtin/show-branch.c b/builtin/show-branch.c
index 4b480d7..1e7bd31 100644
--- a/builtin/show-branch.c
+++ b/builtin/show-branch.c
@@ -728,7 +728,7 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 			static const char *fake_av[2];
 			const char *refname;
 
-			refname = resolve_ref("HEAD", sha1, 1, NULL);
+			refname = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
 			fake_av[0] = xstrdup(refname);
 			fake_av[1] = NULL;
 			av = fake_av;
@@ -791,7 +791,7 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 		}
 	}
 
-	head_p = resolve_ref("HEAD", head_sha1, 1, NULL);
+	head_p = resolve_ref_unsafe("HEAD", head_sha1, 1, NULL);
 	if (head_p) {
 		head_len = strlen(head_p);
 		memcpy(head, head_p, head_len + 1);
diff --git a/builtin/symbolic-ref.c b/builtin/symbolic-ref.c
index dea849c..2ef5962 100644
--- a/builtin/symbolic-ref.c
+++ b/builtin/symbolic-ref.c
@@ -12,7 +12,7 @@ static void check_symref(const char *HEAD, int quiet)
 {
 	unsigned char sha1[20];
 	int flag;
-	const char *refs_heads_master = resolve_ref(HEAD, sha1, 0, &flag);
+	const char *refs_heads_master = resolve_ref_unsafe(HEAD, sha1, 0, &flag);
 
 	if (!refs_heads_master)
 		die("No such ref: %s", HEAD);
diff --git a/cache.h b/cache.h
index 5badece..61f023a 100644
--- a/cache.h
+++ b/cache.h
@@ -866,7 +866,7 @@ extern int read_ref(const char *filename, unsigned char *sha1);
  *
  * errno is sometimes set on errors, but not always.
  */
-extern const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag);
+extern const char *resolve_ref_unsafe(const char *ref, unsigned char *sha1, int reading, int *flag);
 
 extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
 extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
diff --git a/reflog-walk.c b/reflog-walk.c
index 5d81d39..b9b2453 100644
--- a/reflog-walk.c
+++ b/reflog-walk.c
@@ -50,7 +50,7 @@ static struct complete_reflogs *read_complete_reflog(const char *ref)
 	for_each_reflog_ent(ref, read_one_reflog, reflogs);
 	if (reflogs->nr == 0) {
 		unsigned char sha1[20];
-		const char *name = resolve_ref(ref, sha1, 1, NULL);
+		const char *name = resolve_ref_unsafe(ref, sha1, 1, NULL);
 		if (name)
 			for_each_reflog_ent(name, read_one_reflog, reflogs);
 	}
@@ -168,7 +168,7 @@ int add_reflog_for_walk(struct reflog_walk_info *info,
 	else {
 		if (*branch == '\0') {
 			unsigned char sha1[20];
-			const char *head = resolve_ref("HEAD", sha1, 0, NULL);
+			const char *head = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
 			if (!head)
 				die ("No current branch");
 			free(branch);
diff --git a/refs.c b/refs.c
index 44c1c86..9e42e36 100644
--- a/refs.c
+++ b/refs.c
@@ -361,7 +361,7 @@ static int warn_if_dangling_symref(const char *refname, const unsigned char *sha
 	if (!(flags & REF_ISSYMREF))
 		return 0;
 
-	resolves_to = resolve_ref(refname, junk, 0, NULL);
+	resolves_to = resolve_ref_unsafe(refname, junk, 0, NULL);
 	if (!resolves_to || strcmp(resolves_to, d->refname))
 		return 0;
 
@@ -497,7 +497,7 @@ static int get_packed_ref(const char *ref, unsigned char *sha1)
 	return -1;
 }
 
-const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
+const char *resolve_ref_unsafe(const char *ref, unsigned char *sha1, int reading, int *flag)
 {
 	int depth = MAXDEPTH;
 	ssize_t len;
@@ -614,7 +614,7 @@ struct ref_filter {
 
 int read_ref_full(const char *ref, unsigned char *sha1, int reading, int *flags)
 {
-	if (resolve_ref(ref, sha1, reading, flags))
+	if (resolve_ref_unsafe(ref, sha1, reading, flags))
 		return 0;
 	return -1;
 }
@@ -1118,7 +1118,7 @@ int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
 
 		this_result = refs_found ? sha1_from_ref : sha1;
 		mksnpath(fullref, sizeof(fullref), *p, len, str);
-		r = resolve_ref(fullref, this_result, 1, &flag);
+		r = resolve_ref_unsafe(fullref, this_result, 1, &flag);
 		if (r) {
 			if (!refs_found++)
 				*ref = xstrdup(r);
@@ -1148,7 +1148,7 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
 		const char *ref, *it;
 
 		mksnpath(path, sizeof(path), *p, len, str);
-		ref = resolve_ref(path, hash, 1, NULL);
+		ref = resolve_ref_unsafe(path, hash, 1, NULL);
 		if (!ref)
 			continue;
 		if (!stat(git_path("logs/%s", path), &st) &&
@@ -1184,7 +1184,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
 	lock = xcalloc(1, sizeof(struct ref_lock));
 	lock->lock_fd = -1;
 
-	ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
+	ref = resolve_ref_unsafe(ref, lock->old_sha1, mustexist, &type);
 	if (!ref && errno == EISDIR) {
 		/* we are trying to lock foo but we used to
 		 * have foo/bar which now does not exist;
@@ -1197,7 +1197,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
 			error("there are still refs under '%s'", orig_ref);
 			goto error_return;
 		}
-		ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
+		ref = resolve_ref_unsafe(orig_ref, lock->old_sha1, mustexist, &type);
 	}
 	if (type_p)
 	    *type_p = type;
@@ -1360,7 +1360,7 @@ int rename_ref(const char *oldref, const char *newref, const char *logmsg)
 	if (log && S_ISLNK(loginfo.st_mode))
 		return error("reflog for %s is a symlink", oldref);
 
-	symref = resolve_ref(oldref, orig_sha1, 1, &flag);
+	symref = resolve_ref_unsafe(oldref, orig_sha1, 1, &flag);
 	if (flag & REF_ISSYMREF)
 		return error("refname %s is a symbolic ref, renaming it is not supported",
 			oldref);
@@ -1649,7 +1649,7 @@ int write_ref_sha1(struct ref_lock *lock,
 		unsigned char head_sha1[20];
 		int head_flag;
 		const char *head_ref;
-		head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
+		head_ref = resolve_ref_unsafe("HEAD", head_sha1, 1, &head_flag);
 		if (head_ref && (head_flag & REF_ISSYMREF) &&
 		    !strcmp(head_ref, lock->ref_name))
 			log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
@@ -1986,7 +1986,7 @@ int update_ref(const char *action, const char *refname,
 int ref_exists(const char *refname)
 {
 	unsigned char sha1[20];
-	return !!resolve_ref(refname, sha1, 1, NULL);
+	return !!resolve_ref_unsafe(refname, sha1, 1, NULL);
 }
 
 struct ref *find_ref_by_name(const struct ref *list, const char *name)
diff --git a/remote.c b/remote.c
index 6655bb0..73a3809 100644
--- a/remote.c
+++ b/remote.c
@@ -482,7 +482,7 @@ static void read_config(void)
 		return;
 	default_remote_name = xstrdup("origin");
 	current_branch = NULL;
-	head_ref = resolve_ref("HEAD", sha1, 0, &flag);
+	head_ref = resolve_ref_unsafe("HEAD", sha1, 0, &flag);
 	if (head_ref && (flag & REF_ISSYMREF) &&
 	    !prefixcmp(head_ref, "refs/heads/")) {
 		current_branch =
@@ -1007,7 +1007,7 @@ static char *guess_ref(const char *name, struct ref *peer)
 	struct strbuf buf = STRBUF_INIT;
 	unsigned char sha1[20];
 
-	const char *r = resolve_ref(peer->name, sha1, 1, NULL);
+	const char *r = resolve_ref_unsafe(peer->name, sha1, 1, NULL);
 	if (!r)
 		return NULL;
 
@@ -1058,7 +1058,7 @@ static int match_explicit(struct ref *src, struct ref *dst,
 		unsigned char sha1[20];
 		int flag;
 
-		dst_value = resolve_ref(matched_src->name, sha1, 1, &flag);
+		dst_value = resolve_ref_unsafe(matched_src->name, sha1, 1, &flag);
 		if (!dst_value ||
 		    ((flag & REF_ISSYMREF) &&
 		     prefixcmp(dst_value, "refs/heads/")))
diff --git a/transport.c b/transport.c
index 51814b5..e9797c0 100644
--- a/transport.c
+++ b/transport.c
@@ -163,7 +163,7 @@ static void set_upstreams(struct transport *transport, struct ref *refs,
 		/* Follow symbolic refs (mainly for HEAD). */
 		localname = ref->peer_ref->name;
 		remotename = ref->name;
-		tmp = resolve_ref(localname, sha, 1, &flag);
+		tmp = resolve_ref_unsafe(localname, sha, 1, &flag);
 		if (tmp && flag & REF_ISSYMREF &&
 			!prefixcmp(tmp, "refs/heads/"))
 			localname = tmp;
diff --git a/wt-status.c b/wt-status.c
index 70fdb76..cc6dad5 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -119,7 +119,7 @@ void wt_status_prepare(struct wt_status *s)
 	s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
 	s->use_color = -1;
 	s->relative_paths = 1;
-	head = resolve_ref("HEAD", sha1, 0, NULL);
+	head = resolve_ref_unsafe("HEAD", sha1, 0, NULL);
 	s->branch = head ? xstrdup(head) : NULL;
 	s->reference = "HEAD";
 	s->fp = stdout;

-- 
1.7.4.74.g639db
Previous: Nguyễn Thái Ngọc DuyNext: Nguyễn Thái Ngọc Duy
Message 3 of 27 in “nd/resolve-ref v2”
  1. 0/8 nd/resolve-ref v2Nguyễn Thái Ngọc Duy, Nov 17, 2011
  2. 1/8 Convert many resolve_ref() calls to read_ref*() and ref_exists()Nguyễn Thái Ngọc Duy, Nov 17, 2011
  3. 2/8 Rename resolve_ref() to resolve_ref_unsafe()Nguyễn Thái Ngọc Duy, Nov 17, 2011
  4. 3/8 Re-add resolve_ref() that always returns an allocated bufferNguyễn Thái Ngọc Duy, Nov 17, 2011
  5. 4/8 cmd_merge: convert to single exit pointNguyễn Thái Ngọc Duy, Nov 17, 2011
  6. Ramkumar RamachandraNov 17, 2011
  7. Jonathan NiederNov 17, 2011
  8. 5/8 Use resolve_ref() instead of resolve_ref_unsafe()Nguyễn Thái Ngọc Duy, Nov 17, 2011
  9. 6/8 Convert resolve_ref_unsafe+xstrdup to resolve_refNguyễn Thái Ngọc Duy, Nov 17, 2011
  10. Ramkumar RamachandraNov 17, 2011
  11. Nguyen Thai Ngoc DuyNov 18, 2011
  12. 7/8 Guard memory overwriting in resolve_ref_unsafe's static bufferNguyễn Thái Ngọc Duy, Nov 17, 2011
  13. 8/8 Enable GIT_DEBUG_MEMCHECK on git_pathname()Nguyễn Thái Ngọc Duy, Nov 17, 2011
  14. Ramkumar RamachandraNov 17, 2011
  15. Jeff KingNov 17, 2011
  16. Nguyen Thai Ngoc DuyNov 18, 2011
  17. Jeff KingNov 18, 2011
  18. Jonathan NiederNov 18, 2011
  19. Nguyen Thai Ngoc DuyNov 18, 2011
  20. Jeff KingNov 18, 2011
  21. Jonathan NiederNov 18, 2011
  22. Johan HerlandNov 18, 2011
  23. Jonathan NiederNov 18, 2011
  24. Junio C HamanoNov 18, 2011
  25. Bernhard R. LinkNov 18, 2011
  26. Jonathan NiederNov 17, 2011
  27. Nguyen Thai Ngoc DuyDec 6, 2011

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