Make SDL_SetError and friends unconditionally return -1.

This lets us change things like this...

    if (Failed) {
        SDL_SetError("We failed");
        return -1;
    }

...into this...

    if (Failed) {
        return SDL_SetError("We failed");
    }


 Fixes Bugzilla #1778.

src/audio/SDL_audiocvt.c

@@ -970,28 +970,23 @@ SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
 
     /* Sanity check target pointer */
     if (cvt == NULL) {
-        SDL_InvalidParamError("cvt");
-        return -1;
+        return SDL_InvalidParamError("cvt");
     }
     
     /* there are no unsigned types over 16 bits, so catch this up front. */
     if ((SDL_AUDIO_BITSIZE(src_fmt) > 16) && (!SDL_AUDIO_ISSIGNED(src_fmt))) {
-        SDL_SetError("Invalid source format");
-        return -1;
+        return SDL_SetError("Invalid source format");
     }
     if ((SDL_AUDIO_BITSIZE(dst_fmt) > 16) && (!SDL_AUDIO_ISSIGNED(dst_fmt))) {
-        SDL_SetError("Invalid destination format");
-        return -1;
+        return SDL_SetError("Invalid destination format");
     }
 
     /* prevent possible divisions by zero, etc. */
     if ((src_channels == 0) || (dst_channels == 0)) {
-        SDL_SetError("Source or destination channels is zero");
-        return -1;
+        return SDL_SetError("Source or destination channels is zero");
     }
     if ((src_rate == 0) || (dst_rate == 0)) {
-        SDL_SetError("Source or destination rate is zero");
-        return -1;
+        return SDL_SetError("Source or destination rate is zero");
     }
 #ifdef DEBUG_CONVERT
     printf("Build format %04x->%04x, channels %u->%u, rate %d->%d\n",

src/audio/SDL_wave.c

@@ -134,8 +134,7 @@ MS_ADPCM_decode(Uint8 ** audio_buf, Uint32 * audio_len)
         MS_ADPCM_state.wavefmt.channels * sizeof(Sint16);
     *audio_buf = (Uint8 *) SDL_malloc(*audio_len);
     if (*audio_buf == NULL) {
-        SDL_Error(SDL_ENOMEM);
-        return (-1);
+        return SDL_OutOfMemory();
     }
     decoded = *audio_buf;
 
@@ -359,8 +358,7 @@ IMA_ADPCM_decode(Uint8 ** audio_buf, Uint32 * audio_len)
         IMA_ADPCM_state.wavefmt.channels * sizeof(Sint16);
     *audio_buf = (Uint8 *) SDL_malloc(*audio_len);
     if (*audio_buf == NULL) {
-        SDL_Error(SDL_ENOMEM);
-        return (-1);
+        return SDL_OutOfMemory();
     }
     decoded = *audio_buf;
 
@@ -620,14 +618,12 @@ ReadChunk(SDL_RWops * src, Chunk * chunk)
     chunk->length = SDL_ReadLE32(src);
     chunk->data = (Uint8 *) SDL_malloc(chunk->length);
     if (chunk->data == NULL) {
-        SDL_Error(SDL_ENOMEM);
-        return (-1);
+        return SDL_OutOfMemory();
     }
     if (SDL_RWread(src, chunk->data, chunk->length, 1) != 1) {
-        SDL_Error(SDL_EFREAD);
         SDL_free(chunk->data);
         chunk->data = NULL;
-        return (-1);
+        return SDL_Error(SDL_EFREAD);
     }
     return (chunk->length);
 }

src/audio/directsound/SDL_directsound.c

@@ -95,7 +95,7 @@ utf16_to_utf8(const WCHAR *S)
                             (SDL_wcslen(S)+1)*sizeof(WCHAR));
 }
 
-static void
+static int
 SetDSerror(const char *function, int code)
 {
     static const char *error;
@@ -145,8 +145,7 @@ SetDSerror(const char *function, int code)
         SDL_snprintf(errbuf, SDL_arraysize(errbuf), "%s: %s", function,
                      error);
     }
-    SDL_SetError("%s", errbuf);
-    return;
+    return SDL_SetError("%s", errbuf);
 }
 
 
@@ -380,16 +379,14 @@ CreateSecondary(_THIS, HWND focus, WAVEFORMATEX * wavefmt)
     format.dwBufferBytes = numchunks * chunksize;
     if ((format.dwBufferBytes < DSBSIZE_MIN) ||
         (format.dwBufferBytes > DSBSIZE_MAX)) {
-        SDL_SetError("Sound buffer size must be between %d and %d",
-                     DSBSIZE_MIN / numchunks, DSBSIZE_MAX / numchunks);
-        return (-1);
+        return SDL_SetError("Sound buffer size must be between %d and %d",
+                            DSBSIZE_MIN / numchunks, DSBSIZE_MAX / numchunks);
     }
     format.dwReserved = 0;
     format.lpwfxFormat = wavefmt;
     result = IDirectSound_CreateSoundBuffer(sndObj, &format, sndbuf, NULL);
     if (result != DS_OK) {
-        SetDSerror("DirectSound CreateSoundBuffer", result);
-        return (-1);
+        return SetDSerror("DirectSound CreateSoundBuffer", result);
     }
     IDirectSoundBuffer_SetFormat(*sndbuf, wavefmt);
 

src/audio/sun/SDL_sunaudio.c

@@ -332,8 +332,7 @@ SUNAUDIO_OpenDevice(_THIS, const char *devname, int iscapture)
         this->hidden->frequency = 8;
         this->hidden->ulaw_buf = (Uint8 *) SDL_malloc(this->hidden->fragsize);
         if (this->hidden->ulaw_buf == NULL) {
-            SDL_OutOfMemory();
-            return (-1);
+            return SDL_OutOfMemory();
         }
         this->spec.channels = 1;
     } else {
@@ -353,8 +352,7 @@ SUNAUDIO_OpenDevice(_THIS, const char *devname, int iscapture)
     /* Allocate mixing buffer */
     this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->spec.size);
     if (this->hidden->mixbuf == NULL) {
-        SDL_OutOfMemory();
-        return (-1);
+        return SDL_OutOfMemory();
     }
     SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size);