lavf/os_support.h: Fix for unicode filenames on windows.

Fixes #819 #5256 #5281

Signed-off-by: Matt Oliver <protogonoi@gmail.com>

libavformat/file.c

@@ -148,7 +148,11 @@ static int file_check(URLContext *h, int mask)
             ret |= AVIO_FLAG_WRITE;
 #else
     struct stat st;
+#   ifndef _WIN32
     ret = stat(filename, &st);
+#   else
+    ret = win32_stat(filename, &st);
+#   endif
     if (ret < 0)
         return AVERROR(errno);
 

libavformat/os_support.h

@@ -182,6 +182,29 @@ DEF_FS_FUNCTION(unlink, _wunlink, _unlink)
 DEF_FS_FUNCTION(mkdir,  _wmkdir,  _mkdir)
 DEF_FS_FUNCTION(rmdir,  _wrmdir , _rmdir)
 
+#define DEF_FS_FUNCTION2(name, wfunc, afunc, partype)     \
+static inline int win32_##name(const char *filename_utf8, partype par) \
+{                                                         \
+    wchar_t *filename_w;                                  \
+    int ret;                                              \
+                                                          \
+    if (utf8towchar(filename_utf8, &filename_w))          \
+        return -1;                                        \
+    if (!filename_w)                                      \
+        goto fallback;                                    \
+                                                          \
+    ret = wfunc(filename_w, par);                         \
+    av_free(filename_w);                                  \
+    return ret;                                           \
+                                                          \
+fallback:                                                 \
+    /* filename may be be in CP_ACP */                    \
+    return afunc(filename_utf8, par);                     \
+}
+
+DEF_FS_FUNCTION2(access, _waccess, _access, int)
+DEF_FS_FUNCTION2(stat, _wstat64, _stat64, struct stat*)
+
 static inline int win32_rename(const char *src_utf8, const char *dest_utf8)
 {
     wchar_t *src_w, *dest_w;
@@ -231,6 +254,7 @@ fallback:
 #define rename      win32_rename
 #define rmdir       win32_rmdir
 #define unlink      win32_unlink
+#define access      win32_access
 
 #endif