From 4ef9caf5431dbbd23f240a25b69a989aeb9840a4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Sun, 30 Nov 2014 15:24:26 +0700 Subject: path.c: make get_pathname() return strbuf instead of static buffer MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We've been avoiding PATH_MAX whenever possible. This patch makes get_pathname() return a strbuf and updates the callers to take advantage of this. The code is simplified as we no longer need to worry about buffer overflow. vsnpath() behavior is changed slightly: previously it always clears the buffer before writing, now it just appends. Fortunately this is a static function and all of its callers prepare the buffer properly: git_path() gets the buffer from get_pathname() which resets the buffer, the remaining call sites start with STRBUF_INIT'd buffer. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano diff --git a/path.c b/path.c index f68df0c..015c0e4 100644 --- a/path.c +++ b/path.c @@ -16,11 +16,15 @@ static int get_st_mode_bits(const char *path, int *mode) static char bad_path[] = "/bad-path/"; -static char *get_pathname(void) +static struct strbuf *get_pathname(void) { - static char pathname_array[4][PATH_MAX]; + static struct strbuf pathname_array[4] = { + STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT + }; static int index; - return pathname_array[3 & ++index]; + struct strbuf *sb = &pathname_array[3 & ++index]; + strbuf_reset(sb); + return sb; } static char *cleanup_path(char *path) @@ -34,6 +38,13 @@ static char *cleanup_path(char *path) return path; } +static void strbuf_cleanup_path(struct strbuf *sb) +{ + char *path = cleanup_path(sb->buf); + if (path > sb->buf) + strbuf_remove(sb, 0, path - sb->buf); +} + char *mksnpath(char *buf, size_t n, const char *fmt, ...) { va_list args; @@ -49,85 +60,70 @@ char *mksnpath(char *buf, size_t n, const char *fmt, ...) return cleanup_path(buf); } -static char *vsnpath(char *buf, size_t n, const char *fmt, va_list args) +static void vsnpath(struct strbuf *buf, const char *fmt, va_list args) { const char *git_dir = get_git_dir(); - size_t len; - - len = strlen(git_dir); - if (n < len + 1) - goto bad; - memcpy(buf, git_dir, len); - if (len && !is_dir_sep(git_dir[len-1])) - buf[len++] = '/'; - len += vsnprintf(buf + len, n - len, fmt, args); - if (len >= n) - goto bad; - return cleanup_path(buf); -bad: - strlcpy(buf, bad_path, n); - return buf; + strbuf_addstr(buf, git_dir); + if (buf->len && !is_dir_sep(buf->buf[buf->len - 1])) + strbuf_addch(buf, '/'); + strbuf_vaddf(buf, fmt, args); + strbuf_cleanup_path(buf); } char *git_snpath(char *buf, size_t n, const char *fmt, ...) { - char *ret; + struct strbuf sb = STRBUF_INIT; va_list args; va_start(args, fmt); - ret = vsnpath(buf, n, fmt, args); + vsnpath(&sb, fmt, args); va_end(args); - return ret; + if (sb.len >= n) + strlcpy(buf, bad_path, n); + else + memcpy(buf, sb.buf, sb.len + 1); + strbuf_release(&sb); + return buf; } char *git_pathdup(const char *fmt, ...) { - char path[PATH_MAX], *ret; + struct strbuf path = STRBUF_INIT; va_list args; va_start(args, fmt); - ret = vsnpath(path, sizeof(path), fmt, args); + vsnpath(&path, fmt, args); va_end(args); - return xstrdup(ret); + return strbuf_detach(&path, NULL); } char *mkpathdup(const char *fmt, ...) { - char *path; struct strbuf sb = STRBUF_INIT; va_list args; - va_start(args, fmt); strbuf_vaddf(&sb, fmt, args); va_end(args); - path = xstrdup(cleanup_path(sb.buf)); - - strbuf_release(&sb); - return path; + strbuf_cleanup_path(&sb); + return strbuf_detach(&sb, NULL); } char *mkpath(const char *fmt, ...) { va_list args; - unsigned len; - char *pathname = get_pathname(); - + struct strbuf *pathname = get_pathname(); va_start(args, fmt); - len = vsnprintf(pathname, PATH_MAX, fmt, args); + strbuf_vaddf(pathname, fmt, args); va_end(args); - if (len >= PATH_MAX) - return bad_path; - return cleanup_path(pathname); + return cleanup_path(pathname->buf); } char *git_path(const char *fmt, ...) { - char *pathname = get_pathname(); + struct strbuf *pathname = get_pathname(); va_list args; - char *ret; - va_start(args, fmt); - ret = vsnpath(pathname, PATH_MAX, fmt, args); + vsnpath(pathname, fmt, args); va_end(args); - return ret; + return pathname->buf; } void home_config_paths(char **global, char **xdg, char *file) @@ -160,41 +156,27 @@ void home_config_paths(char **global, char **xdg, char *file) char *git_path_submodule(const char *path, const char *fmt, ...) { - char *pathname = get_pathname(); - struct strbuf buf = STRBUF_INIT; + struct strbuf *buf = get_pathname(); const char *git_dir; va_list args; - unsigned len; - - len = strlen(path); - if (len > PATH_MAX-100) - return bad_path; - strbuf_addstr(&buf, path); - if (len && path[len-1] != '/') - strbuf_addch(&buf, '/'); - strbuf_addstr(&buf, ".git"); + strbuf_addstr(buf, path); + if (buf->len && buf->buf[buf->len - 1] != '/') + strbuf_addch(buf, '/'); + strbuf_addstr(buf, ".git"); - git_dir = read_gitfile(buf.buf); + git_dir = read_gitfile(buf->buf); if (git_dir) { - strbuf_reset(&buf); - strbuf_addstr(&buf, git_dir); + strbuf_reset(buf); + strbuf_addstr(buf, git_dir); } - strbuf_addch(&buf, '/'); - - if (buf.len >= PATH_MAX) - return bad_path; - memcpy(pathname, buf.buf, buf.len + 1); - - strbuf_release(&buf); - len = strlen(pathname); + strbuf_addch(buf, '/'); va_start(args, fmt); - len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args); + strbuf_vaddf(buf, fmt, args); va_end(args); - if (len >= PATH_MAX) - return bad_path; - return cleanup_path(pathname); + strbuf_cleanup_path(buf); + return buf->buf; } int validate_headref(const char *path) -- cgit v0.10.2-6-g49f6