compat: add realpath used by test_media_subitems()

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

compat/realpath.c

+/*****************************************************************************
+ * realpath.c: POSIX realpath replacement
+ *****************************************************************************
+ * Copyright © 2016 VLC authors and VideoLAN
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <errno.h>
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+char *realpath(const char * restrict relpath, char * restrict resolved_path)
+{
+    if (relpath == NULL)
+    {
+        errno = EINVAL;
+        return NULL;
+    }
+
+#ifdef _WIN32
+    int len = MultiByteToWideChar( CP_UTF8, 0, relpath, -1, NULL, 0 );
+    if (len == 0)
+        return NULL;
+
+    wchar_t *wrelpath = malloc(len * sizeof (wchar_t));
+    if (wrelpath == NULL)
+        return NULL;
+
+    MultiByteToWideChar( CP_UTF8, 0, relpath, -1, wrelpath, len );
+
+    wchar_t *wfullpath = _wfullpath( NULL, wrelpath, _MAX_PATH );
+    free(wrelpath);
+    if (wfullpath != NULL)
+    {
+        size_t len = WideCharToMultiByte( CP_UTF8, 0, wfullpath, -1, NULL, 0, NULL, NULL );
+        if (len != 0)
+        {
+            if (resolved_path != NULL)
+                len = len >= _MAX_PATH ? _MAX_PATH : len;
+            else
+                resolved_path = (char *)malloc(len);
+
+            if (resolved_path != NULL)
+                WideCharToMultiByte( CP_UTF8, 0, wfullpath, -1, resolved_path, len, NULL, NULL );
+            free(wfullpath);
+            return resolved_path;
+        }
+        free(wfullpath);
+    }
+#else
+    (void)resolved_path;
+#endif
+    errno = EACCES;
+    return NULL;
+}

configure.ac

@@ -605,6 +605,8 @@ AC_CHECK_FUNC(fdatasync,,
   [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if missing.])
 ])
 
+VLC_REPLACE_DECL([realpath], [#include <stdlib.h>])
+
 dnl mingw64 implements those as static inline, not functions with C linkage
 VLC_REPLACE_DECL([asprintf], [#include <stdio.h>])
 VLC_REPLACE_DECL([vasprintf], [#include <stdio.h>])

include/vlc_fixups.h

@@ -481,6 +481,10 @@ void freeaddrinfo (struct addrinfo *res);
 #define nanf(tagp) NAN
 #endif
 
+#ifndef HAVE_REALPATH
+char *realpath(const char * restrict pathname, char * restrict resolved_path);
+#endif
+
 #ifdef _WIN32
 FILE *vlc_win32_tmpfile(void);
 #endif