[PATCH v3 02/25] Convert git_snpath() to strbuf_git_path()

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

In the previous patch, git_snpath() is modified to take a strbuf
buffer from get_pathname() because vsnpath() needs that. But that
makes it awkward because git_snpath() receives a pre-allocated buffer
from outside and has to copy data back.

Rename it to strbuf_git_path() and make it receive strbuf directly.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 builtin/checkout.c | 22 +++++++++---------
 cache.h            |  4 ++--
 path.c             |  8 +------
 refs.c             | 66 +++++++++++++++++++++++++++++++++++-------------------
 refs.h             |  2 +-
 5 files changed, 57 insertions(+), 45 deletions(-)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 5df3837..0570e41 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -585,18 +585,20 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 		if (opts->new_orphan_branch) {
 			if (opts->new_branch_log && !log_all_ref_updates) {
 				int temp;
-				char log_file[PATH_MAX];
+				struct strbuf log_file = STRBUF_INIT;
 				char *ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
+				int ret;
 
 				temp = log_all_ref_updates;
 				log_all_ref_updates = 1;
-				if (log_ref_setup(ref_name, log_file, sizeof(log_file))) {
+				ret = log_ref_setup(ref_name, &log_file);
+				log_all_ref_updates = temp;
+				strbuf_release(&log_file);
+				if (ret) {
 					fprintf(stderr, _("Can not do reflog for '%s'\n"),
 					    opts->new_orphan_branch);
-					log_all_ref_updates = temp;
 					return;
 				}
-				log_all_ref_updates = temp;
 			}
 		}
 		else
@@ -651,14 +653,10 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 					new->name);
 			}
 		}
-		if (old->path && old->name) {
-			char log_file[PATH_MAX], ref_file[PATH_MAX];
-
-			git_snpath(log_file, sizeof(log_file), "logs/%s", old->path);
-			git_snpath(ref_file, sizeof(ref_file), "%s", old->path);
-			if (!file_exists(ref_file) && file_exists(log_file))
-				remove_path(log_file);
-		}
+		if (old->path && old->name &&
+		    !file_exists(git_path("%s", old->path)) &&
+		     file_exists(git_path("logs/%s", old->path)))
+			remove_path(git_path("logs/%s", old->path));
 	}
 	remove_branch_state();
 	strbuf_release(&msg);
diff --git a/cache.h b/cache.h
index dc040fb..8d3697e 100644
--- a/cache.h
+++ b/cache.h
@@ -646,8 +646,8 @@ extern int check_repository_format(void);
 
 extern char *mksnpath(char *buf, size_t n, const char *fmt, ...)
 	__attribute__((format (printf, 3, 4)));
-extern char *git_snpath(char *buf, size_t n, const char *fmt, ...)
-	__attribute__((format (printf, 3, 4)));
+extern void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
+	__attribute__((format (printf, 2, 3)));
 extern char *git_pathdup(const char *fmt, ...)
 	__attribute__((format (printf, 1, 2)));
 extern char *mkpathdup(const char *fmt, ...)
diff --git a/path.c b/path.c
index 1a1b784..fe3f844 100644
--- a/path.c
+++ b/path.c
@@ -70,18 +70,12 @@ static void vsnpath(struct strbuf *buf, const char *fmt, va_list args)
 	strbuf_cleanup_path(buf);
 }
 
-char *git_snpath(char *buf, size_t n, const char *fmt, ...)
+void strbuf_git_path(struct strbuf *sb, const char *fmt, ...)
 {
-	struct strbuf *sb = get_pathname();
 	va_list args;
 	va_start(args, fmt);
 	vsnpath(sb, fmt, args);
 	va_end(args);
-	if (sb->len >= n)
-		strlcpy(buf, bad_path, n);
-	else
-		memcpy(buf, sb->buf, sb->len + 1);
-	return buf;
 }
 
 char *git_pathdup(const char *fmt, ...)
diff --git a/refs.c b/refs.c
index 89228e2..434bd5e 100644
--- a/refs.c
+++ b/refs.c
@@ -1325,10 +1325,12 @@ static const char *handle_missing_loose_ref(const char *refname,
 
 const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
 {
+	struct strbuf sb_path = STRBUF_INIT;
 	int depth = MAXDEPTH;
 	ssize_t len;
 	char buffer[256];
 	static char refname_buffer[256];
+	const char *ret;
 
 	if (flag)
 		*flag = 0;
@@ -1337,15 +1339,17 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 		return NULL;
 
 	for (;;) {
-		char path[PATH_MAX];
+		const char *path;
 		struct stat st;
 		char *buf;
 		int fd;
 
 		if (--depth < 0)
-			return NULL;
+			goto fail;
 
-		git_snpath(path, sizeof(path), "%s", refname);
+		strbuf_reset(&sb_path);
+		strbuf_git_path(&sb_path, "%s", refname);
+		path = sb_path.buf;
 
 		/*
 		 * We might have to loop back here to avoid a race
@@ -1359,10 +1363,11 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 	stat_ref:
 		if (lstat(path, &st) < 0) {
 			if (errno == ENOENT)
-				return handle_missing_loose_ref(refname, sha1,
-								reading, flag);
+				ret = handle_missing_loose_ref(refname, sha1,
+							       reading, flag);
 			else
-				return NULL;
+				ret = NULL;
+			goto done;
 		}
 
 		/* Follow "normalized" - ie "refs/.." symlinks by hand */
@@ -1373,7 +1378,7 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 					/* inconsistent with lstat; retry */
 					goto stat_ref;
 				else
-					return NULL;
+					goto fail;
 			}
 			buffer[len] = 0;
 			if (starts_with(buffer, "refs/") &&
@@ -1389,7 +1394,7 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 		/* Is it a directory? */
 		if (S_ISDIR(st.st_mode)) {
 			errno = EISDIR;
-			return NULL;
+			goto fail;
 		}
 
 		/*
@@ -1402,12 +1407,13 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 				/* inconsistent with lstat; retry */
 				goto stat_ref;
 			else
-				return NULL;
+				goto fail;
 		}
+
 		len = read_in_full(fd, buffer, sizeof(buffer)-1);
 		close(fd);
 		if (len < 0)
-			return NULL;
+			goto fail;
 		while (len && isspace(buffer[len-1]))
 			len--;
 		buffer[len] = '\0';
@@ -1424,9 +1430,10 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 			    (buffer[40] != '\0' && !isspace(buffer[40]))) {
 				if (flag)
 					*flag |= REF_ISBROKEN;
-				return NULL;
+				goto fail;
 			}
-			return refname;
+			ret = refname;
+			goto done;
 		}
 		if (flag)
 			*flag |= REF_ISSYMREF;
@@ -1436,10 +1443,15 @@ const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int rea
 		if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
 			if (flag)
 				*flag |= REF_ISBROKEN;
-			return NULL;
+			goto fail;
 		}
 		refname = strcpy(refname_buffer, buf);
 	}
+fail:
+	ret = NULL;
+done:
+	strbuf_release(&sb_path);
+	return ret;
 }
 
 char *resolve_refdup(const char *ref, unsigned char *sha1, int reading, int *flag)
@@ -2717,17 +2729,19 @@ static int copy_msg(char *buf, const char *msg)
 	return cp - buf;
 }
 
-int log_ref_setup(const char *refname, char *logfile, int bufsize)
+int log_ref_setup(const char *refname, struct strbuf *sb_logfile)
 {
 	int logfd, oflags = O_APPEND | O_WRONLY;
+	const char *logfile;
 
-	git_snpath(logfile, bufsize, "logs/%s", refname);
+	strbuf_git_path(sb_logfile, "logs/%s", refname);
+	logfile = sb_logfile->buf;
 	if (log_all_ref_updates &&
 	    (starts_with(refname, "refs/heads/") ||
 	     starts_with(refname, "refs/remotes/") ||
 	     starts_with(refname, "refs/notes/") ||
 	     !strcmp(refname, "HEAD"))) {
-		if (safe_create_leading_directories(logfile) < 0)
+		if (safe_create_leading_directories(sb_logfile->buf) < 0)
 			return error("unable to create directory for %s",
 				     logfile);
 		oflags |= O_CREAT;
@@ -2762,20 +2776,22 @@ static int log_ref_write(const char *refname, const unsigned char *old_sha1,
 	int logfd, result, written, oflags = O_APPEND | O_WRONLY;
 	unsigned maxlen, len;
 	int msglen;
-	char log_file[PATH_MAX];
+	struct strbuf sb_log_file = STRBUF_INIT;
+	const char *log_file;
 	char *logrec;
 	const char *committer;
 
 	if (log_all_ref_updates < 0)
 		log_all_ref_updates = !is_bare_repository();
 
-	result = log_ref_setup(refname, log_file, sizeof(log_file));
+	result = log_ref_setup(refname, &sb_log_file);
 	if (result)
-		return result;
+		goto done;
+	log_file = sb_log_file.buf;
 
 	logfd = open(log_file, oflags);
 	if (logfd < 0)
-		return 0;
+		goto done;
 	msglen = msg ? strlen(msg) : 0;
 	committer = git_committer_info(0);
 	maxlen = strlen(committer) + msglen + 100;
@@ -2788,9 +2804,13 @@ static int log_ref_write(const char *refname, const unsigned char *old_sha1,
 		len += copy_msg(logrec + len - 1, msg) - 1;
 	written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
 	free(logrec);
-	if (close(logfd) != 0 || written != len)
-		return error("Unable to append to %s", log_file);
-	return 0;
+	if (close(logfd) != 0 || written != len) {
+		error("Unable to append to %s", log_file);
+		result = -1;
+	}
+done:
+	strbuf_release(&sb_log_file);
+	return result;
 }
 
 static int is_branch(const char *refname)
diff --git a/refs.h b/refs.h
index 87a1a79..783033a 100644
--- a/refs.h
+++ b/refs.h
@@ -166,7 +166,7 @@ extern void unlock_ref(struct ref_lock *lock);
 extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg);
 
 /** Setup reflog before using. **/
-int log_ref_setup(const char *ref_name, char *logfile, int bufsize);
+int log_ref_setup(const char *ref_name, struct strbuf *logfile);
 
 /** Reads log for the value of ref during at_time. **/
 extern int read_ref_at(const char *refname, unsigned long at_time, int cnt,
-- 
1.8.5.2.240.g8478abd