start some read optimizations

diff --git a/src/libFLAC/bitbuffer.c b/src/libFLAC/bitbuffer.c
index bc94d20..42a729e 100644 (file)
--- a/src/libFLAC/bitbuffer.c
+++ b/src/libFLAC/bitbuffer.c
@@ -24,8 +24,11 @@
 #include "private/bitmath.h"
 #include "private/crc.h"
 
+/* This should be at least twice as large as the largest number of bytes required to represent any 'number' (in any encoding) you are going to read. */
 static const unsigned FLAC__BITBUFFER_DEFAULT_CAPACITY = 65536; /* bytes */
 
+static const byte byte_bit_to_mask_[] = { 128, 64, 32, 16, 8, 4, 2, 1 };
+
 #ifdef min
 #undef min
 #endif
@@ -106,7 +109,7 @@ static bool bitbuffer_read_from_client_(FLAC__BitBuffer *bb, bool (*read_callbac
                if(!bitbuffer_resize_(bb, 16))
                        return false;
        }
-       /* finally, read in some data; if OK, go back to read_bit_, else fail */
+       /* finally, read in some data */
        bytes = bb->capacity - bb->bytes;
        if(!read_callback(bb->buffer+bb->bytes, &bytes, client_data))
                return false;
@@ -941,8 +944,6 @@ bool FLAC__bitbuffer_zero_pad_to_byte_boundary(FLAC__BitBuffer *bb)
 
 bool FLAC__bitbuffer_peek_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
 {
-       static const byte mask[] = { 128, 64, 32, 16, 8, 4, 2, 1 };
-
        /* to avoid a drastic speed penalty we don't:
        assert(bb != 0);
        assert(bb->buffer != 0);
@@ -951,7 +952,7 @@ bool FLAC__bitbuffer_peek_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_ca
 
        while(1) {
                if(bb->total_consumed_bits < bb->total_bits) {
-                       *val = (bb->buffer[bb->consumed_bytes] & mask[bb->consumed_bits])? 1 : 0;
+                       *val = (bb->buffer[bb->consumed_bytes] & byte_bit_to_mask_[bb->consumed_bits])? 1 : 0;
                        return true;
                }
                else {
@@ -963,8 +964,6 @@ bool FLAC__bitbuffer_peek_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_ca
 
 bool FLAC__bitbuffer_read_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
 {
-       static const byte mask[] = { 128, 64, 32, 16, 8, 4, 2, 1 };
-
        /* to avoid a drastic speed penalty we don't:
        assert(bb != 0);
        assert(bb->buffer != 0);
@@ -973,7 +972,7 @@ bool FLAC__bitbuffer_read_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_ca
 
        while(1) {
                if(bb->total_consumed_bits < bb->total_bits) {
-                       *val = (bb->buffer[bb->consumed_bytes] & mask[bb->consumed_bits])? 1 : 0;
+                       *val = (bb->buffer[bb->consumed_bytes] & byte_bit_to_mask_[bb->consumed_bits])? 1 : 0;
                        bb->consumed_bits++;
                        if(bb->consumed_bits == 8) {
                                FLAC__CRC16_UPDATE(bb->buffer[bb->consumed_bytes], bb->read_crc16);
@@ -992,8 +991,6 @@ bool FLAC__bitbuffer_read_bit(FLAC__BitBuffer *bb, unsigned *val, bool (*read_ca
 
 bool FLAC__bitbuffer_read_bit_to_uint32(FLAC__BitBuffer *bb, uint32 *val, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
 {
-       static const byte mask[] = { 128, 64, 32, 16, 8, 4, 2, 1 };
-
        /* to avoid a drastic speed penalty we don't:
        assert(bb != 0);
        assert(bb->buffer != 0);
@@ -1003,7 +1000,7 @@ bool FLAC__bitbuffer_read_bit_to_uint32(FLAC__BitBuffer *bb, uint32 *val, bool (
        while(1) {
                if(bb->total_consumed_bits < bb->total_bits) {
                        *val <<= 1;
-                       *val |= (bb->buffer[bb->consumed_bytes] & mask[bb->consumed_bits])? 1 : 0;
+                       *val |= (bb->buffer[bb->consumed_bytes] & byte_bit_to_mask_[bb->consumed_bits])? 1 : 0;
                        bb->consumed_bits++;
                        if(bb->consumed_bits == 8) {
                                FLAC__CRC16_UPDATE(bb->buffer[bb->consumed_bytes], bb->read_crc16);
@@ -1022,8 +1019,6 @@ bool FLAC__bitbuffer_read_bit_to_uint32(FLAC__BitBuffer *bb, uint32 *val, bool (
 
 bool FLAC__bitbuffer_read_bit_to_uint64(FLAC__BitBuffer *bb, uint64 *val, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
 {
-       static const byte mask[] = { 128, 64, 32, 16, 8, 4, 2, 1 };
-
        /* to avoid a drastic speed penalty we don't:
        assert(bb != 0);
        assert(bb->buffer != 0);
@@ -1033,7 +1028,7 @@ bool FLAC__bitbuffer_read_bit_to_uint64(FLAC__BitBuffer *bb, uint64 *val, bool (
        while(1) {
                if(bb->total_consumed_bits < bb->total_bits) {
                        *val <<= 1;
-                       *val |= (bb->buffer[bb->consumed_bytes] & mask[bb->consumed_bits])? 1 : 0;
+                       *val |= (bb->buffer[bb->consumed_bytes] & byte_bit_to_mask_[bb->consumed_bits])? 1 : 0;
                        bb->consumed_bits++;
                        if(bb->consumed_bits == 8) {
                                FLAC__CRC16_UPDATE(bb->buffer[bb->consumed_bytes], bb->read_crc16);
@@ -1051,6 +1046,7 @@ bool FLAC__bitbuffer_read_bit_to_uint64(FLAC__BitBuffer *bb, uint64 *val, bool (
 }
 
 bool FLAC__bitbuffer_read_raw_uint32(FLAC__BitBuffer *bb, uint32 *val, unsigned bits, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
+#ifdef FLAC__NO_MANUAL_INLINING
 {
        unsigned i;
 
@@ -1066,6 +1062,55 @@ bool FLAC__bitbuffer_read_raw_uint32(FLAC__BitBuffer *bb, uint32 *val, unsigned
        }
        return true;
 }
+#else
+{
+       unsigned i, bits_ = bits;
+       uint32 v = 0;
+
+       assert(bb != 0);
+       assert(bb->buffer != 0);
+
+       assert(bits <= 32);
+       assert((bb->capacity*8) * 2 >= bits);
+
+       while(bb->total_consumed_bits + bits > bb->total_bits) {
+               if(!bitbuffer_read_from_client_(bb, read_callback, client_data))
+                       return false;
+       }
+       if(bb->consumed_bits) {
+               i = 8 - bb->consumed_bits;
+               if(i <= bits_) {
+                       v = bb->buffer[bb->consumed_bytes] & (0xff >> bb->consumed_bits);
+                       bits_ -= i;
+                       FLAC__CRC16_UPDATE(bb->buffer[bb->consumed_bytes], bb->read_crc16);
+                       bb->consumed_bytes++;
+                       bb->consumed_bits = 0;
+               }
+               else {
+                       *val = (bb->buffer[bb->consumed_bytes] & (0xff >> bb->consumed_bits)) >> (i-bits_);
+                       bb->consumed_bits += bits_;
+                       bb->total_consumed_bits += bits_;
+                       return true;
+               }
+       }
+       while(bits_ >= 8) {
+               v <<= 8;
+               v |= bb->buffer[bb->consumed_bytes];
+               bits_ -= 8;
+               FLAC__CRC16_UPDATE(bb->buffer[bb->consumed_bytes], bb->read_crc16);
+               bb->consumed_bytes++;
+               /* bb->consumed_bits is already 0 */
+       }
+       if(bits_ > 0) {
+               v <<= bits_;
+               v |= (bb->buffer[bb->consumed_bytes] >> (8-bits_));
+               bb->consumed_bits = bits_;
+       }
+       bb->total_consumed_bits += bits;
+       *val = v;
+       return true;
+}
+#endif
 
 bool FLAC__bitbuffer_read_raw_int32(FLAC__BitBuffer *bb, int32 *val, unsigned bits, bool (*read_callback)(byte buffer[], unsigned *bytes, void *client_data), void *client_data)
 {