abspath: convert absolute_path() to strbuf

Move most of the code of absolute_path() into the new function
strbuf_add_absolute_path() and in the process transform it to use
struct strbuf and xgetcwd() instead of a PATH_MAX-sized buffer,
which can be too small on some file systems.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 42 deletions

diff --git a/abspath.c b/abspath.c
index 6aa328f80..5edb4e781 100644
--- a/abspath.c
+++ b/abspath.c
@@ -140,54 +140,16 @@ const char *real_path_if_valid(const char *path)
 	return real_path_internal(path, 0);
 }
 
-static const char *get_pwd_cwd(void)
-{
-	static char cwd[PATH_MAX + 1];
-	char *pwd;
-	struct stat cwd_stat, pwd_stat;
-	if (getcwd(cwd, PATH_MAX) == NULL)
-		return NULL;
-	pwd = getenv("PWD");
-	if (pwd && strcmp(pwd, cwd)) {
-		stat(cwd, &cwd_stat);
-		if ((cwd_stat.st_dev || cwd_stat.st_ino) &&
-		    !stat(pwd, &pwd_stat) &&
-		    pwd_stat.st_dev == cwd_stat.st_dev &&
-		    pwd_stat.st_ino == cwd_stat.st_ino) {
-			strlcpy(cwd, pwd, PATH_MAX);
-		}
-	}
-	return cwd;
-}
-
 /*
  * Use this to get an absolute path from a relative one. If you want
  * to resolve links, you should use real_path.
- *
- * If the path is already absolute, then return path. As the user is
- * never meant to free the return value, we're safe.
  */
 const char *absolute_path(const char *path)
 {
-	static char buf[PATH_MAX + 1];
-
-	if (!*path) {
-		die("The empty string is not a valid path");
-	} else if (is_absolute_path(path)) {
-		if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
-			die("Too long path: %.*s", 60, path);
-	} else {
-		size_t len;
-		const char *fmt;
-		const char *cwd = get_pwd_cwd();
-		if (!cwd)
-			die_errno("Cannot determine the current working directory");
-		len = strlen(cwd);
-		fmt = (len > 0 && is_dir_sep(cwd[len - 1])) ? "%s%s" : "%s/%s";
-		if (snprintf(buf, PATH_MAX, fmt, cwd, path) >= PATH_MAX)
-			die("Too long path: %.*s", 60, path);
-	}
-	return buf;
+	static struct strbuf sb = STRBUF_INIT;
+	strbuf_reset(&sb);
+	strbuf_add_absolute_path(&sb, path);
+	return sb.buf;
 }
 
 /*