Improved error handling, and implemented celt_strerror()

libcelt/celt.c

@@ -125,7 +125,11 @@ CELTEncoder *celt_encoder_create(const CELTMode *mode, int channels, int *error)
    CELTEncoder *st;
 
    if (check_mode(mode) != CELT_OK)
+   {
+      if (error)
+         *error = CELT_INVALID_MODE;
       return NULL;
+   }
    if (channels < 0 || channels > 2)
    {
       celt_warning("Only mono and stereo supported");
@@ -139,7 +143,11 @@ CELTEncoder *celt_encoder_create(const CELTMode *mode, int channels, int *error)
    st = celt_alloc(sizeof(CELTEncoder));
    
    if (st==NULL)
+   {
+      if (error)
+         *error = CELT_ALLOC_FAIL;
       return NULL;
+   }
    st->marker = ENCODERPARTIAL;
    st->mode = mode;
    st->frame_size = N;
@@ -175,11 +183,15 @@ CELTEncoder *celt_encoder_create(const CELTMode *mode, int channels, int *error)
 #endif   
        && (st->preemph_memE!=NULL) && (st->preemph_memD!=NULL))
    {
+      if (error)
+         *error = CELT_OK;
       st->marker   = ENCODERVALID;
       return st;
    }
    /* If the setup fails for some reason deallocate it. */
    celt_encoder_destroy(st);  
+   if (error)
+      *error = CELT_ALLOC_FAIL;
    return NULL;
 }
 
@@ -1046,7 +1058,11 @@ CELTDecoder *celt_decoder_create(const CELTMode *mode, int channels, int *error)
    CELTDecoder *st;
 
    if (check_mode(mode) != CELT_OK)
+   {
+      if (error)
+         *error = CELT_INVALID_MODE;
       return NULL;
+   }
    if (channels < 0 || channels > 2)
    {
       celt_warning("Only mono and stereo supported");
@@ -1060,7 +1076,11 @@ CELTDecoder *celt_decoder_create(const CELTMode *mode, int channels, int *error)
    st = celt_alloc(sizeof(CELTDecoder));
 
    if (st==NULL)
+   {
+      if (error)
+         *error = CELT_ALLOC_FAIL;
       return NULL;
+   }
 
    st->marker = DECODERPARTIAL;
    st->mode = mode;
@@ -1081,11 +1101,15 @@ CELTDecoder *celt_decoder_create(const CELTMode *mode, int channels, int *error)
    if ((st->decode_mem!=NULL) && (st->out_mem!=NULL) && (st->oldBandE!=NULL) &&
        (st->preemph_memD!=NULL))
    {
+      if (error)
+         *error = CELT_OK;
       st->marker = DECODERVALID;
       return st;
    }
    /* If the setup fails for some reason deallocate it. */
    celt_decoder_destroy(st);
+   if (error)
+      *error = CELT_ALLOC_FAIL;
    return NULL;
 }
 
@@ -1441,3 +1465,22 @@ bad_request:
       va_end(ap);
   return CELT_UNIMPLEMENTED;
 }
+
+const char *celt_strerror(int error)
+{
+   static const char *error_strings[8] = {
+      "success",
+      "invalid argument",
+      "invalid mode",
+      "internal error",
+      "corrupted stream",
+      "request not implemented",
+      "invalid state",
+      "memory allocation failed"
+   };
+   if (error > 0 || error < -7)
+      return "unknown error";
+   else 
+      return error_strings[-error];
+}
+

libcelt/celt.h

@@ -69,6 +69,8 @@ extern "C" {
 #define CELT_UNIMPLEMENTED    -5
 /** An encoder or decoder structure is invalid or already freed */
 #define CELT_INVALID_STATE    -6
+/** Memory allocation has failed */
+#define CELT_ALLOC_FAIL    -6
 
 /* Requests */
 #define CELT_GET_MODE_REQUEST    1
@@ -265,6 +267,8 @@ EXPORT int celt_decoder_ctl(CELTDecoder * st, int request, ...);
 
 /*  @} */
 
+const char *celt_strerror(int error);
+
 
 #ifdef __cplusplus
 }

libcelt/modes.h

@@ -39,7 +39,7 @@
 #include "psy.h"
 #include "pitch.h"
 
-#define CELT_BITSTREAM_VERSION 0x8000000a
+#define CELT_BITSTREAM_VERSION 0x8000000b
 
 #ifdef STATIC_MODES
 #include "static_modes.h"

libcelt/testcelt.c

@@ -108,10 +108,16 @@ int main(int argc, char *argv[])
    
    enc = celt_encoder_create(mode, channels, &err);
    if (err != 0)
+   {
+      fprintf(stderr, "Failed to create the encoder: %s\n", celt_strerror(err));
       return 1;
+   }
    dec = celt_decoder_create(mode, channels, &err);
    if (err != 0)
+   {
+      fprintf(stderr, "Failed to create the decoder: %s\n", celt_strerror(err));
       return 1;
+   }
 
    if (argc>7)
    {