move compatibility code for file access from audio.c to compat.h

src/util/compat.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#if defined __unix__
+# include <unistd.h>
+#elif defined _WIN32
+# include <io.h>
+#else
+# error platform not supported!
+#endif
+
+// define the constants if they haven't been
+#ifndef F_OK
+# define F_OK 0
+#endif
+#ifndef X_OK
+# define X_OK 1
+#endif
+#ifndef W_OK
+# define W_OK 2
+#endif
+#ifndef R_OK
+# define R_OK 4
+#endif
+
+enum faccess_perms {
+    FA_F = F_OK, // test for file's existence
+    FA_X = X_OK, // test for executing permission
+    FA_W = W_OK, // test for write permissions
+    FA_R = R_OK, // test for read permissions
+};
+
+// tests a files access with F_OK, X_OK, R_OK, W_OK OR'd together
+static inline int faccess(char const* restrict fname, int perms) {
+#if defined __unix__
+    return !access(fname, perms);
+#elif defined _WIN32
+    return !_access(fname, perms);
+#endif
+}

src/window/audio.c

@@ -7,17 +7,8 @@
 #include <stdlib.h>
 #include <string.h>
 
-#ifdef __unix__
-# include <unistd.h>
-# define fexists(fname) (access(fname, F_OK) == 0)
-#elif _WIN32
-# include <io.h>
-# define fexists(fname) (_access(fname, 0) == 0)
-#else
-# error platform not supported!
-#endif
-
 #include "../error.h"
+#include "../util/compat.h"
 
 static void audiomixer(void* const userdata, uint8_t* const stream, int const len) {
     memset(stream, 0, len);            // clear the playing audio
@@ -174,8 +165,8 @@ audiodata audio_wav_load(audiodevice const* dev, char const* fpath) {
 
     debug("loading audio file '%s'...", fpath);
 
-    if (!fexists(fpath)) {
+    if (!faccess(fpath, FA_R)) {
-        error("%s:%u couldn't find audio file '%s'!", __FILE_NAME__, __LINE__, fpath);
+        error("%s:%u audio file either isn't readable or doesn't exist. path: '%s'!", __FILE_NAME__, __LINE__, fpath);
         return (audiodata){0};
     }