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Shift the callback handlers to methods.
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This removes some of the last standalone functions in the bitstream module.
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@tuffy
tuffy committed Aug 18, 2014
1 parent d200a01 commit 6e14965
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Showing 14 changed files with 286 additions and 334 deletions.
283 changes: 118 additions & 165 deletions src/bitstream.c
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124 changes: 70 additions & 54 deletions src/bitstream.h
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Original file line number Diff line number Diff line change
Expand Up @@ -118,7 +118,6 @@ typedef struct BitstreamReader_s {
struct bs_exception* exceptions;
struct br_mark_stack* mark_stacks;

struct bs_callback* callbacks_used;
struct bs_exception* exceptions_used;

/*returns "count" number of unsigned bits from the current stream
Expand Down Expand Up @@ -277,6 +276,33 @@ typedef struct BitstreamReader_s {
void
(*close)(struct BitstreamReader_s* bs);

/*pushes a callback function into the stream
which is called on every byte read*/
void
(*add_callback)(struct BitstreamReader_s* bs,
bs_callback_f callback,
void* data);

/*pushes the given callback onto the callback stack
data from "callback" is copied onto a new internal struct
it does not need to be allocated from the heap*/
void
(*push_callback)(struct BitstreamReader_s* bs,
struct bs_callback* callback);

/*pops the most recently added callback from the stack
if "callback" is not NULL, data from the popped callback
is copied to that struct*/
void
(*pop_callback)(struct BitstreamReader_s* bs,
struct bs_callback* callback);

/*explicitly call all set callbacks as if "byte" had been read
from the input stream*/
void
(*call_callbacks)(struct BitstreamReader_s* bs,
uint8_t byte);

/*pushes the stream's current position onto the given mark stack
all pushed marks should be unmarked once no longer needed*/
Expand Down Expand Up @@ -645,40 +671,25 @@ br_substream_append(struct BitstreamReader_s *stream,
unsigned bytes);


/*unattached, BitstreamReader functions*/


/*adds the given callback to BitstreamReader's callback stack*/
/*bs->add_callback(bs, callback, data) method*/
void
br_add_callback(BitstreamReader *bs, bs_callback_f callback, void *data);

/*explicitly passes "byte" to the set callbacks,
as if the byte were read from the input stream*/

/*bs->push_callback(bs, callback) method*/
void
br_call_callbacks(BitstreamReader *bs, uint8_t byte);
br_push_callback(BitstreamReader *bs, struct bs_callback *callback);

/*removes the most recently added callback, if any
if "callback" is not NULL, the popped callback's data is copied to it
for possible restoration via "br_push_callback"

this is often paired with bs_push_callback in order
to temporarily disable a callback, for example:
/*bs->pop_callback(bs, callback) method*/
void
br_pop_callback(BitstreamReader *bs, struct bs_callback *callback);

br_pop_callback(reader, &saved_callback); //save callback for later
unchecksummed_value = bs->read(bs, 16); //read a value
br_push_callback(reader, &saved_callback); //restore saved callback
*/
#define br_pop_callback(bs, callback) __br_pop_callback((bs), (callback), __FILE__, __LINE__)

/*bs->call_callbacks(bs, byte) method*/
void
__br_pop_callback(BitstreamReader *bs, struct bs_callback *callback,
const char *file, int lineno);
br_call_callbacks(BitstreamReader *bs, uint8_t byte);

/*pushes the given callback back onto the callback stack
note that the data from "callback" is copied onto a new internal struct;
it does not need to be allocated from the heap*/
void
br_push_callback(BitstreamReader *bs, struct bs_callback *callback);


/*Called by the read functions if one attempts to read past
Expand Down Expand Up @@ -779,7 +790,6 @@ typedef struct BitstreamWriter_s {
struct bs_exception* exceptions;
struct bw_mark_stack* mark_stacks;

struct bs_callback* callbacks_used;
struct bs_exception* exceptions_used;

/*writes the given value as "count" number of unsigned bits
Expand Down Expand Up @@ -956,6 +966,33 @@ typedef struct BitstreamWriter_s {
void
(*close)(struct BitstreamWriter_s* bs);

/*pushes a callback function into the stream
which is called on every byte read*/
void
(*add_callback)(struct BitstreamWriter_s* bs,
bs_callback_f callback,
void* data);

/*pushes the given callback onto the callback stack
data from "callback" is copied onto a new internal struct
it does not need to be allocated from the heap*/
void
(*push_callback)(struct BitstreamWriter_s* bs,
struct bs_callback* callback);

/*pops the most recently added callback from the stack
if "callback" is not NULL, data from the popped callback
is copied to that struct*/
void
(*pop_callback)(struct BitstreamWriter_s* bs,
struct bs_callback* callback);

/*explicitly call all set callbacks as if "byte" had been read
from the input stream*/
void
(*call_callbacks)(struct BitstreamWriter_s* bs,
uint8_t byte);

/*pushes the stream's current position onto the given mark stack
all pushed marks should be unmarked once no longer needed
Expand Down Expand Up @@ -1326,40 +1363,19 @@ bw_unmark_r_a(BitstreamWriter *bs, int mark_id);
/*unattached, BitstreamWriter functions*/


/*adds a callback function, which is called on every byte written
the function's arguments are the written byte and a generic
pointer to some other data structure
*/
/*bs->add_callback(bs, callback, data) method*/
void
bw_add_callback(BitstreamWriter* bs, bs_callback_f callback, void *data);

/*removes the most recently added callback, if any
if "callback" is not NULL, the popped callback's data is copied to it
for possible restoration via "bw_push_callback"
this is often paired with bs_push_callback in order
to temporarily disable a callback, for example:
bw_pop_callback(writer, &saved_callback); //save callback for later
bs->write(bs, 16, 0xAB); //write a value
bw_push_callback(writer, &saved_callback); //restore saved callback
*/

#define bw_pop_callback(bs, callback) __bw_pop_callback((bs), (callback), __FILE__, __LINE__)
bw_add_callback(BitstreamWriter *bs, bs_callback_f callback, void *data);

/*bs->push_callback(bs, callback) method*/
void
__bw_pop_callback(BitstreamWriter* bs, struct bs_callback* callback,
const char *file, int lineno);
bw_push_callback(BitstreamWriter *bs, struct bs_callback *callback);

/*pushes the given callback back onto the callback stack
note that the data from "callback" is copied onto a new internal struct;
it does not need to be allocated from the heap*/
/*bs->pop_callback(bs, callback) method*/
void
bw_push_callback(BitstreamWriter* bs, struct bs_callback* callback);
bw_pop_callback(BitstreamWriter *bs, struct bs_callback *callback);

/*explicitly passes "byte" to the set callbacks,
as if the byte were written to the output stream*/
/*bs->call_callbacks(bs, byte) method*/
void
bw_call_callbacks(BitstreamWriter *bs, uint8_t byte);

Expand Down
40 changes: 20 additions & 20 deletions src/decoders/flac.c
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Original file line number Diff line number Diff line change
Expand Up @@ -211,13 +211,13 @@ FlacDecoder_read(decoders_FlacDecoder* self, PyObject *args)

if (!setjmp(*br_try(self->bitstream))) {
/*add callback for CRC16 calculation*/
br_add_callback(self->bitstream, (bs_callback_f)flac_crc16, &crc16);
self->bitstream->add_callback(self->bitstream, (bs_callback_f)flac_crc16, &crc16);

/*read frame header*/
if ((error = flacdec_read_frame_header(self->bitstream,
&(self->streaminfo),
&frame_header)) != OK) {
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);
PyErr_SetString(PyExc_ValueError, FlacDecoder_strerror(error));
br_etry(self->bitstream);
return NULL;
Expand All @@ -235,7 +235,7 @@ FlacDecoder_read(decoders_FlacDecoder* self, PyObject *args)
flacdec_subframe_bits_per_sample(&frame_header,
channel),
self->subframe_data->append(self->subframe_data))) != OK) {
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);
PyErr_SetString(PyExc_ValueError, FlacDecoder_strerror(error));
br_etry(self->bitstream);
return NULL;
Expand All @@ -249,7 +249,7 @@ FlacDecoder_read(decoders_FlacDecoder* self, PyObject *args)
/*check CRC-16*/
self->bitstream->byte_align(self->bitstream);
self->bitstream->read(self->bitstream, 16);
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);
if (crc16 != 0) {
PyErr_SetString(PyExc_ValueError, "invalid checksum in frame");
br_etry(self->bitstream);
Expand All @@ -260,7 +260,7 @@ FlacDecoder_read(decoders_FlacDecoder* self, PyObject *args)
self->remaining_samples -= frame_header.block_size;
} else {
/*handle I/O error during read*/
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);
PyErr_SetString(PyExc_IOError, "EOF reading frame");
br_etry(self->bitstream);
return NULL;
Expand Down Expand Up @@ -375,9 +375,9 @@ FlacDecoder_offsets(decoders_FlacDecoder* self, PyObject *args)
unsigned samples;
unsigned long long offset;

br_add_callback(self->bitstream,
(bs_callback_f)increment_offset,
&total_offset);
self->bitstream->add_callback(self->bitstream,
(bs_callback_f)increment_offset,
&total_offset);

while (self->remaining_samples > 0) {
self->subframe_data->reset(self->subframe_data);
Expand Down Expand Up @@ -433,13 +433,13 @@ FlacDecoder_offsets(decoders_FlacDecoder* self, PyObject *args)
}

self->stream_finalized = 1;
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);

return offsets;
error:
Py_XDECREF(offsets);
br_etry(self->bitstream);
br_pop_callback(self->bitstream, NULL);
self->bitstream->pop_callback(self->bitstream, NULL);

return NULL;
}
Expand Down Expand Up @@ -718,18 +718,18 @@ flacdec_read_frame_header(BitstreamReader *bitstream,
uint8_t crc8 = 0;

if (!setjmp(*br_try(bitstream))) {
br_add_callback(bitstream, (bs_callback_f)flac_crc8, &crc8);
bitstream->add_callback(bitstream, (bs_callback_f)flac_crc8, &crc8);

/*read and verify sync code*/
if (bitstream->read(bitstream, 14) != 0x3FFE) {
br_pop_callback(bitstream, NULL);
bitstream->pop_callback(bitstream, NULL);
br_etry(bitstream);
return ERR_INVALID_SYNC_CODE;
}

/*read and verify reserved bit*/
if (bitstream->read(bitstream, 1) != 0) {
br_pop_callback(bitstream, NULL);
bitstream->pop_callback(bitstream, NULL);
br_etry(bitstream);
return ERR_INVALID_RESERVED_BIT;
}
Expand Down Expand Up @@ -820,7 +820,7 @@ flacdec_read_frame_header(BitstreamReader *bitstream,
bitstream->read(bitstream, 8);

/*no more I/O after this point*/
br_pop_callback(bitstream, NULL);
bitstream->pop_callback(bitstream, NULL);
br_etry(bitstream);

if (crc8 != 0)
Expand All @@ -845,7 +845,7 @@ flacdec_read_frame_header(BitstreamReader *bitstream,
return OK;
} else {
/*push read error to calling function*/
br_pop_callback(bitstream, NULL);
bitstream->pop_callback(bitstream, NULL);
br_etry(bitstream);
br_abort(bitstream);
return OK; /*won't get here*/
Expand Down Expand Up @@ -1416,13 +1416,13 @@ int main(int argc, char* argv[]) {
uint16_t crc16 = 0;

/*add callback for CRC16 calculation*/
br_add_callback(reader, (bs_callback_f)flac_crc16, &crc16);
reader->add_callback(reader, (bs_callback_f)flac_crc16, &crc16);

/*read frame header*/
if ((error = flacdec_read_frame_header(reader,
&streaminfo,
&frame_header)) != OK) {
br_pop_callback(reader, NULL);
reader->pop_callback(reader, NULL);
br_etry(reader);
fprintf(stderr, "*** Error: %s\n", FlacDecoder_strerror(error));
goto error;
Expand All @@ -1440,7 +1440,7 @@ int main(int argc, char* argv[]) {
flacdec_subframe_bits_per_sample(&frame_header,
channel),
subframe_data->append(subframe_data))) != OK) {
br_pop_callback(reader, NULL);
reader->pop_callback(reader, NULL);
br_etry(reader);
fprintf(stderr, "*** Error: %s\n",
FlacDecoder_strerror(error));
Expand All @@ -1455,7 +1455,7 @@ int main(int argc, char* argv[]) {
/*check CRC-16*/
reader->byte_align(reader);
reader->read(reader, 16);
br_pop_callback(reader, NULL);
reader->pop_callback(reader, NULL);
if (crc16 != 0) {
br_etry(reader);
fprintf(stderr, "*** Error: invalid checksum in frame\n");
Expand All @@ -1468,7 +1468,7 @@ int main(int argc, char* argv[]) {
br_etry(reader);
} else {
/*handle I/O error during read*/
br_pop_callback(reader, NULL);
reader->pop_callback(reader, NULL);
br_etry(reader);
fprintf(stderr, "*** I/O Error reading frame\n");
goto error;
Expand Down
8 changes: 4 additions & 4 deletions src/decoders/mlp.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -258,10 +258,10 @@ read_mlp_frame(MLPDecoder* decoder,
uint8_t parity;
uint8_t CRC8;

br_add_callback(bs, mlp_checkdata_callback, &checkdata);
bs->add_callback(bs, mlp_checkdata_callback, &checkdata);
bs->substream_append(bs, decoder->substream_reader,
substream0->info.substream_end - 2);
br_pop_callback(bs, NULL);
bs->pop_callback(bs, NULL);

parity = (uint8_t)bs->read(bs, 8);
if ((parity ^ checkdata.parity) != 0xA9) {
Expand Down Expand Up @@ -334,12 +334,12 @@ read_mlp_frame(MLPDecoder* decoder,
unsigned CRC8;
unsigned parity;

br_add_callback(bs, mlp_checkdata_callback, &checkdata);
bs->add_callback(bs, mlp_checkdata_callback, &checkdata);
bs->substream_append(bs, decoder->substream_reader,
substream1->info.substream_end -
substream0->info.substream_end -
2);
br_pop_callback(bs, NULL);
bs->pop_callback(bs, NULL);

parity = (uint8_t)bs->read(bs, 8);
if ((parity ^ checkdata.parity) != 0xA9) {
Expand Down
4 changes: 2 additions & 2 deletions src/decoders/oggflac.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -110,7 +110,7 @@ OggFlacDecoder_init(decoders_OggFlacDecoder *self,
audiotools__MD5Init(&(self->md5));

/*add callback for CRC16 calculation*/
br_add_callback(self->packet, (bs_callback_f)flac_crc16, &(self->crc16));
self->packet->add_callback(self->packet, (bs_callback_f)flac_crc16, &(self->crc16));

/*setup a framelist generator function*/
if ((self->audiotools_pcm = open_audiotools_pcm()) == NULL)
Expand Down Expand Up @@ -466,7 +466,7 @@ int main(int argc, char* argv[]) {
audiotools__MD5Init(&md5);

/*add callback for CRC16 calculation*/
br_add_callback(packet, (bs_callback_f)flac_crc16, &crc16);
packet->add_callback(packet, (bs_callback_f)flac_crc16, &crc16);

/*decode the next FrameList from the stream*/
br_substream_reset(packet);
Expand Down
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