Remove unnecessary checks for output buffer length and some optimizations.

diff --git a/sbc/sbc.c b/sbc/sbc.c
index ebf4a9d..c3d3947 100644 (file)
--- a/sbc/sbc.c
+++ b/sbc/sbc.c
@@ -976,9 +976,6 @@ static int sbc_pack_frame(uint8_t *data, struct sbc_frame *frame, size_t len)
 
        u_int32_t scalefactor[2][8];    /* derived from frame->scale_factor */
 
-       if (len < 4)
-               return -1;
-
        /* Clear first 4 bytes of data (that's the constant length part of the
         * SBC header) */
        memset(data, 0, 4);
@@ -1037,11 +1034,11 @@ static int sbc_pack_frame(uint8_t *data, struct sbc_frame *frame, size_t len)
        data[2] = frame->bitpool;
 
        if ((frame->channel_mode == MONO || frame->channel_mode == DUAL_CHANNEL) &&
-                       frame->bitpool > 16 * frame->subbands)
+                       frame->bitpool > frame->subbands << 4)
                return -5;
 
        if ((frame->channel_mode == STEREO || frame->channel_mode == JOINT_STEREO) &&
-                       frame->bitpool > 32 * frame->subbands)
+                       frame->bitpool > frame->subbands << 5)
                return -5;
 
        /* Can't fill in crc yet */
@@ -1118,31 +1115,25 @@ static int sbc_pack_frame(uint8_t *data, struct sbc_frame *frame, size_t len)
                        }
                }
 
-               if (len * 8 < produced + frame->subbands)
-                       return -1;
-
                data[4] = 0;
                for (sb = 0; sb < frame->subbands - 1; sb++)
                        data[4] |= ((frame->join >> sb) & 0x01) << (7 - sb);
 
                if (frame->subbands == 4)
-                       crc_header[crc_pos / 8] = data[4] & 0xf0;
+                       crc_header[crc_pos >> 3] = data[4] & 0xf0;
                else
-                       crc_header[crc_pos / 8] = data[4];
+                       crc_header[crc_pos >> 3] = data[4];
 
                produced += frame->subbands;
                crc_pos += frame->subbands;
        }
 
-       if (len * 8 < produced + (4 * frame->subbands * frame->channels))
-               return -1;
-
        for (ch = 0; ch < frame->channels; ch++) {
                for (sb = 0; sb < frame->subbands; sb++) {
                        if (produced % 8 == 0)
                                data[produced / 8] = 0;
-                       data[produced / 8] |= ((frame->scale_factor[ch][sb] & 0x0F) << (4 - (produced % 8)));
-                       crc_header[crc_pos / 8] |= ((frame->scale_factor[ch][sb] & 0x0F) << (4 - (crc_pos % 8)));
+                       data[produced >> 3] |= ((frame->scale_factor[ch][sb] & 0x0F) << (4 - (produced % 8)));
+                       crc_header[crc_pos >> 3] |= ((frame->scale_factor[ch][sb] & 0x0F) << (4 - (crc_pos % 8)));
 
                        produced += 4;
                        crc_pos += 4;
@@ -1168,23 +1159,15 @@ static int sbc_pack_frame(uint8_t *data, struct sbc_frame *frame, size_t len)
                                                                levels[ch][sb]) >> 1);
                                else
                                        frame->audio_sample[blk][ch][sb] = 0;
-                       }
-               }
-       }
 
-       for (blk = 0; blk < frame->blocks; blk++) {
-               for (ch = 0; ch < frame->channels; ch++) {
-                       for (sb = 0; sb < frame->subbands; sb++) {
                                if (bits[ch][sb] != 0) {
                                        for (bit = 0; bit < bits[ch][sb]; bit++) {
                                                int b;  /* A bit */
-                                               if (produced > len * 8)
-                                                       return -1;
                                                if (produced % 8 == 0)
-                                                       data[produced / 8] = 0;
+                                                       data[produced >> 3] = 0;
                                                b = ((frame->audio_sample[blk][ch][sb]) >>
                                                                (bits[ch][sb] - bit - 1)) & 0x01;
-                                               data[produced / 8] |= b << (7 - (produced % 8));
+                                               data[produced >> 3] |= b << (7 - (produced % 8));
                                                produced++;
                                        }
                                }
@@ -1195,7 +1178,7 @@ static int sbc_pack_frame(uint8_t *data, struct sbc_frame *frame, size_t len)
        if (produced % 8 != 0)
                produced += 8 - (produced % 8);
 
-       return produced / 8;
+       return produced >> 3;
 }
 
 struct sbc_priv {