win32: code shrink directory tests

Add a function to check if a file is a directory and use it in
various places.

Replace some uses of S_ISDIR() with a test of the Windows file
attributes.

Saves 32-48 bytes.

1 files changed, 19 insertions, 15 deletions

diff --git a/win32/mingw.c b/win32/mingw.c
index bea800435..bf9b75a7f 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -220,6 +220,7 @@ static int get_dev_fd(const char *filename)
         return -1;
 }
 
+static int mingw_is_directory(const char *path);
 #undef open
 int mingw_open (const char *filename, int oflags, ...)
 {
@@ -247,8 +248,7 @@ int mingw_open (const char *filename, int oflags, ...)
                 update_special_fd(dev, fd);
         }
         else if ((oflags & O_ACCMODE) != O_RDONLY && errno == EACCES) {
-                DWORD attrs = GetFileAttributes(filename);
-                if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
+                if (mingw_is_directory(filename))
                         errno = EISDIR;
         }
         return fd;
@@ -355,7 +355,7 @@ static inline mode_t file_attr_to_st_mode(DWORD attr)
         return fMode;
 }
 
-static inline int get_file_attr(const char *fname, WIN32_FILE_ATTRIBUTE_DATA *fdata)
+static int get_file_attr(const char *fname, WIN32_FILE_ATTRIBUTE_DATA *fdata)
 {
         size_t len;
 
@@ -592,6 +592,14 @@ static DWORD is_symlink(const char *pathname)
         return 0;
 }
 
+static int mingw_is_directory(const char *path)
+{
+        WIN32_FILE_ATTRIBUTE_DATA fdata;
+
+        return get_file_attr(path, &fdata) == 0 &&
+                                (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY);
+}
+
 #if ENABLE_FEATURE_EXTRA_FILE_DATA
 static int count_subdirs(const char *pathname)
 {
@@ -669,7 +677,7 @@ static int do_lstat(int follow, const char *file_name, struct mingw_stat *buf)
                         buf->st_mtim = filetime_to_timespec(&(fdata.ftLastWriteTime));
                         buf->st_ctim = filetime_to_timespec(&(fdata.ftCreationTime));
                 }
-                buf->st_nlink = S_ISDIR(buf->st_mode) ? 2 : 1;
+                buf->st_nlink = (buf->st_attr & FILE_ATTRIBUTE_DIRECTORY) ? 2 : 1;
 
 #if ENABLE_FEATURE_EXTRA_FILE_DATA
                 flags = FILE_FLAG_BACKUP_SEMANTICS;
@@ -682,7 +690,7 @@ static int do_lstat(int follow, const char *file_name, struct mingw_stat *buf)
                                 buf->st_dev = hdata.dwVolumeSerialNumber;
                                 buf->st_ino = hdata.nFileIndexLow |
                                                 (((ino_t)hdata.nFileIndexHigh)<<32);
-                                buf->st_nlink = S_ISDIR(buf->st_mode) ?
+                                buf->st_nlink = (buf->st_attr & FILE_ATTRIBUTE_DIRECTORY) ?
                                                         count_subdirs(file_name) :
                                                         hdata.nNumberOfLinks;
                         }
@@ -700,7 +708,7 @@ static int do_lstat(int follow, const char *file_name, struct mingw_stat *buf)
                 /* Get actual size of compressed/sparse files */
                 low = GetCompressedFileSize(file_name, &high);
                 if ((low == INVALID_FILE_SIZE && GetLastError() != NO_ERROR) ||
-                                S_ISDIR(buf->st_mode)) {
+                                (buf->st_attr & FILE_ATTRIBUTE_DIRECTORY)) {
                         size = buf->st_size;
                 }
                 else {
@@ -782,13 +790,14 @@ int mingw_fstat(int fd, struct mingw_stat *buf)
                 buf->st_dev = fdata.dwVolumeSerialNumber;
                 buf->st_ino = fdata.nFileIndexLow |
                         (((uint64_t)fdata.nFileIndexHigh)<<32);
-                buf->st_nlink = S_ISDIR(buf->st_mode) ? 2 : fdata.nNumberOfLinks;
+                buf->st_nlink = (buf->st_attr & FILE_ATTRIBUTE_DIRECTORY) ?
+                        2 : fdata.nNumberOfLinks;
 #endif
  success:
 #if !ENABLE_FEATURE_EXTRA_FILE_DATA
                 buf->st_dev = 0;
                 buf->st_ino = 0;
-                buf->st_nlink = S_ISDIR(buf->st_mode) ? 2 : 1;
+                buf->st_nlink = (buf->st_attr & FILE_ATTRIBUTE_DIRECTORY) ? 2 : 1;
 #endif
                 buf->st_rdev = 0;
                 buf->st_uid = DEFAULT_UID;
@@ -1256,7 +1265,6 @@ int link(const char *oldpath, const char *newpath)
 int symlink(const char *target, const char *linkpath)
 {
         DWORD flag = SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
-        struct stat st;
         DECLARE_PROC_ADDR(BOOLEAN, CreateSymbolicLinkA, LPCSTR, LPCSTR, DWORD);
         char *targ, *relative = NULL;
 
@@ -1271,7 +1279,7 @@ int symlink(const char *target, const char *linkpath)
                                                 (int)(name - linkpath), linkpath, target);
         }
 
-        if (stat(relative ?: target, &st) != -1 && S_ISDIR(st.st_mode))
+        if (mingw_is_directory(relative ?: target))
                 flag |= SYMBOLIC_LINK_FLAG_DIRECTORY;
         free(relative);
 
@@ -1638,12 +1646,8 @@ int mingw_chdir(const char *dirname)
 #undef chmod
 int mingw_chmod(const char *path, int mode)
 {
-        WIN32_FILE_ATTRIBUTE_DATA fdata;
-
-        if ( get_file_attr(path, &fdata) == 0 &&
-                        fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY ) {
+        if (mingw_is_directory(path))
                 mode |= 0222;
-        }
 
         return chmod(path, mode);
 }