win32: code shrink

There are a few places in mingw.c where we want to determine if a
file is a symbolic link.  Previously these called mingw_lstat()
which collects far more information than is actually needed.

Create a new is_symlink() function which does the minimum work
necessary.

1 files changed, 16 insertions, 9 deletions

diff --git a/win32/mingw.c b/win32/mingw.c
index d4855a7e7..c59d8a7c8 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -557,7 +557,8 @@ static uid_t file_owner(HANDLE fh)
 }
 #endif
 
-static int is_symlink(DWORD attr, const char *pathname, WIN32_FIND_DATAA *fbuf)
+static int get_symlink_data(DWORD attr, const char *pathname,
+                                        WIN32_FIND_DATAA *fbuf)
 {
         if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
                 HANDLE handle = FindFirstFileA(pathname, fbuf);
@@ -570,6 +571,16 @@ static int is_symlink(DWORD attr, const char *pathname, WIN32_FIND_DATAA *fbuf)
         return 0;
 }
 
+static int is_symlink(const char *pathname)
+{
+        WIN32_FILE_ATTRIBUTE_DATA fdata;
+        WIN32_FIND_DATAA fbuf;
+
+        if (!get_file_attr(pathname, &fdata))
+                return get_symlink_data(fdata.dwFileAttributes, pathname, &fbuf);
+        return 0;
+}
+
 /* If follow is true then act like stat() and report on the link
  * target. Otherwise report on the link itself.
  */
@@ -592,7 +603,7 @@ static int do_lstat(int follow, const char *file_name, struct mingw_stat *buf)
                 buf->st_gid = DEFAULT_GID;
                 buf->st_dev = buf->st_rdev = 0;
 
-                if (is_symlink(fdata.dwFileAttributes, file_name, &findbuf)) {
+                if (get_symlink_data(fdata.dwFileAttributes, file_name, &findbuf)) {
                         char *name = auto_string(xmalloc_realpath(file_name));
 
                         if (follow) {
@@ -942,14 +953,13 @@ char *mingw_getcwd(char *pointer, int len)
 #undef rename
 int mingw_rename(const char *pold, const char *pnew)
 {
-        struct mingw_stat st;
         DWORD attrs;
 
         /*
          * For non-symlinks, try native rename() first to get errno right.
          * It is based on MoveFile(), which cannot overwrite existing files.
          */
-        if (mingw_lstat(pold, &st) || !S_ISLNK(st.st_mode)) {
+        if (!is_symlink(pold)) {
                 if (!rename(pold, pnew))
                         return 0;
                 if (errno != EEXIST)
@@ -1420,11 +1430,10 @@ int mingw_mkdir(const char *path, int mode UNUSED_PARAM)
 #undef chdir
 int mingw_chdir(const char *dirname)
 {
-        struct stat st;
         int ret = -1;
         const char *realdir = dirname;
 
-        if (lstat(dirname, &st) == 0 && S_ISLNK(st.st_mode)) {
+        if (is_symlink(dirname)) {
                 realdir = auto_string(xmalloc_readlink(dirname));
                 if (realdir)
                         fix_path_case((char *)realdir);
@@ -1496,7 +1505,6 @@ int fcntl(int fd, int cmd, ...)
 int mingw_unlink(const char *pathname)
 {
         int ret;
-        struct stat st;
 
         /* read-only files cannot be removed */
         chmod(pathname, 0666);
@@ -1504,10 +1512,9 @@ int mingw_unlink(const char *pathname)
         ret = unlink(pathname);
         if (ret == -1 && errno == EACCES) {
                 /* a symlink to a directory needs to be removed by calling rmdir */
-                if (lstat(pathname, &st) == 0 && S_ISLNK(st.st_mode)) {
+                if (is_symlink(pathname)) {
                         return rmdir(pathname);
                 }
-                errno = EACCES;
         }
         return ret;
 }