use a common function for opening regular files

Fixes #514

src/midi/fluid_midi.c

@@ -99,13 +99,7 @@ int fluid_is_midifile(const char *filename)
 
     do
     {
-        if(!fluid_file_test(filename, G_FILE_TEST_IS_REGULAR))
-        {
-            return retcode;
-        }
-
-        // file seems to exist and is a regular file or a symlink to such
-        if((fp = FLUID_FOPEN(filename, "rb")) == NULL)
+        if((fp = fluid_file_open(filename, NULL)) == NULL)
         {
             return retcode;
         }

src/sfloader/fluid_defsfont.c

@@ -436,7 +436,7 @@ int fluid_defsfont_load(fluid_defsfont_t *defsfont, const fluid_file_callbacks_t
 
     if(sfdata == NULL)
     {
-        FLUID_LOG(FLUID_ERR, "Couldn't load soundfont file");
+        /* error message already printed */
         return FLUID_FAILED;
     }
 

src/sfloader/fluid_sffile.c

@@ -340,13 +340,7 @@ int fluid_is_soundfont(const char *filename)
 
     do
     {
-        if(!fluid_file_test(filename, G_FILE_TEST_IS_REGULAR))
-        {
-            return retcode;
-        }
-
-        // file seems to exist and is a regular file or a symlink to such
-        if((fp = FLUID_FOPEN(filename, "rb")) == NULL)
+        if((fp = fluid_file_open(filename, NULL)) == NULL)
         {
             return retcode;
         }

src/sfloader/fluid_sfont.c

@@ -24,26 +24,14 @@
 
 void *default_fopen(const char *path)
 {
-    FILE* handle;
+    const char* msg;
+    FILE* handle = fluid_file_open(path, &msg);
 
-    if(!fluid_file_test(path, G_FILE_TEST_EXISTS))
+    if(handle == NULL)
     {
-        FLUID_LOG(FLUID_ERR, "fluid_sfloader_load(): Unable to load non-existent file. ('%s')", path);
-        return NULL;
-    }
-
-    if(!fluid_file_test(path, G_FILE_TEST_IS_REGULAR))
-    {
-        FLUID_LOG(FLUID_ERR, "fluid_sfloader_load(): Refusing to load non-regular file! ('%s')", path);
-        return NULL;
+        FLUID_LOG(FLUID_ERR, "fluid_sfloader_load(): Failed to open '%s': %s", path, msg);
     }
-
-    if((handle = FLUID_FOPEN(path, "rb")) == NULL)
-    {
-        FLUID_LOG(FLUID_ERR, "fluid_sfloader_load(): Specified file does not exists or insufficient permissions to open it! ('%s')", path);
-        return NULL;
-    }
-
+
     return handle;
 }
 

src/utils/fluid_sys.c

@@ -1610,3 +1610,36 @@ void delete_fluid_server_socket(fluid_server_socket_t *server_socket)
 }
 
 #endif // NETWORK_SUPPORT
+
+FILE* fluid_file_open(const char* path, const char** errMsg)
+{
+    static const char ErrExist[] = "File does not exist.";
+    static const char ErrRegular[] = "File is not regular, refusing to open it.";
+    static const char ErrNull[] = "File does not exists or insufficient permissions to open it.";
+
+    FILE* handle = NULL;
+
+    if(!g_file_test(path, G_FILE_TEST_EXISTS))
+    {
+        if(errMsg != NULL)
+        {
+            *errMsg = ErrExist;
+        }
+    }
+    else if(!g_file_test(path, G_FILE_TEST_IS_REGULAR))
+    {
+        if(errMsg != NULL)
+        {
+            *errMsg = ErrRegular;
+        }
+    }
+    else if((handle = FLUID_FOPEN(path, "rb")) == NULL)
+    {
+        if(errMsg != NULL)
+        {
+            *errMsg = ErrNull;
+        }
+    }
+
+    return handle;
+}

src/utils/fluid_sys.h

@@ -485,7 +485,7 @@ fluid_ostream_t fluid_socket_get_ostream(fluid_socket_t sock);
 typedef GStatBuf fluid_stat_buf_t;
 #endif
 
-#define fluid_file_test g_file_test
+FILE* fluid_file_open(const char* filename, const char** errMsg);
 
 /* Profiling */
 #if WITH_PROFILING