mirror of
https://github.com/claunia/flac.git
synced 2025-12-16 18:54:26 +00:00
add support for id3v2 tags to levels 1 and 2, better bad metadata handling, fix bug with merge_padding
This commit is contained in:
@@ -59,8 +59,8 @@
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2, which allows you to edit all the metadata for a file in memory and
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write it out all at once.
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@@@@WATCHOUT: levels 1 and 2 do not support id3v2 tags at the front of the
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file. You will get an error that it is not a valid FLAC file.
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All levels know how to skip over and not disturb an ID3v2 tag at the
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front of the file.
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******************************************************************************/
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/******************************************************************************
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@@ -77,7 +77,7 @@ extern "C" {
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/***********************************************************************
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* level 0
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* ---------------------------------------------------------------------
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* Only one routine to read the STREAMINFO. Skips any id3v2 tag at the
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* Only one routine to read the STREAMINFO. Skips any ID3v2 tag at the
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* head of the file. Useful for file-based player plugins.
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*
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* Provide the address of a FLAC__StreamMetaData_StreamInfo object to
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@@ -137,6 +137,7 @@ typedef enum {
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR,
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FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR,
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@@ -325,6 +326,7 @@ typedef enum {
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FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE,
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FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE,
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FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE,
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FLAC__METADATA_CHAIN_STATUS_BAD_METADATA,
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FLAC__METADATA_CHAIN_STATUS_READ_ERROR,
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FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR,
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FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR,
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@@ -201,6 +201,7 @@ const char *FLAC__MetaData_SimpleIteratorStatusString[] = {
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_ERROR_OPENING_FILE",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_A_FLAC_FILE",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR",
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"FLAC__METADATA_SIMPLE_ITERATOR_STATUS_WRITE_ERROR",
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@@ -701,6 +702,7 @@ const char *FLAC__MetaData_ChainStatusString[] = {
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"FLAC__METADATA_CHAIN_STATUS_ERROR_OPENING_FILE",
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"FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE",
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"FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE",
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"FLAC__METADATA_CHAIN_STATUS_BAD_METADATA",
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"FLAC__METADATA_CHAIN_STATUS_READ_ERROR",
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"FLAC__METADATA_CHAIN_STATUS_SEEK_ERROR",
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"FLAC__METADATA_CHAIN_STATUS_WRITE_ERROR",
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@@ -1039,7 +1041,6 @@ void FLAC__metadata_chain_sort_padding(FLAC__MetaData_Chain *chain)
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* the small number of nodes that we deal with.
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*/
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for(i = 0, node = chain->head; i < chain->nodes; i++) {
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node->data->is_last = false; /* we'll fix at the end */
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if(node->data->type == FLAC__METADATA_TYPE_PADDING) {
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save = node->next;
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chain_remove_node_(chain, node);
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@@ -1724,6 +1725,12 @@ FLAC__bool read_metadata_block_header_(FLAC__MetaData_SimpleIterator *iterator)
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iterator->type = (FLAC__MetaDataType)(raw_header[0] & 0x7f);
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iterator->length = unpack_uint32_(raw_header + 1, 3);
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/* do some checking */
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if(iterator->type > FLAC__METADATA_TYPE_VORBIS_COMMENT) {
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iterator->status = FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA;
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return false;
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}
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return true;
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}
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@@ -2302,24 +2309,53 @@ FLAC__bool simple_iterator_pop_(FLAC__MetaData_SimpleIterator *iterator)
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unsigned seek_to_first_metadata_block_(FILE *f)
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{
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FLAC__byte signature[FLAC__STREAM_METADATA_HEADER_LENGTH];
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FLAC__byte buffer[4];
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size_t n;
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unsigned i;
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FLAC__ASSERT(0 != f);
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FLAC__ASSERT(FLAC__STREAM_SYNC_LENGTH == 4);
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/*@@@@ skip id3v2, change comment about id3v2 in metadata.h*/
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/* skip any id3v2 tag */
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errno = 0;
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n = fread(buffer, 1, 4, f);
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if(errno)
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return 1;
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else if(n != 4)
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return 2;
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else if(0 == memcmp(buffer, "ID3", 3)) {
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unsigned tag_length = 0;
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/* search for the fLaC signature */
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if(fread(signature, 1, FLAC__STREAM_METADATA_HEADER_LENGTH, f) == FLAC__STREAM_METADATA_HEADER_LENGTH) {
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if(0 == memcmp(FLAC__STREAM_SYNC_STRING, signature, FLAC__STREAM_SYNC_LENGTH)) {
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return 0;
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/* skip to the tag length */
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if(fseek(f, 2, SEEK_CUR) < 0)
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return 1;
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/* read the length */
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for(i = 0; i < 4; i++) {
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if(fread(buffer, 1, 1, f) < 1 || buffer[0] & 0x80)
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return 1;
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tag_length <<= 7;
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tag_length |= (buffer[0] & 0x7f);
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}
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else {
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/* skip the rest of the tag */
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if(fseek(f, tag_length, SEEK_CUR) < 0)
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return 1;
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/* read the stream sync code */
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errno = 0;
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n = fread(buffer, 1, 4, f);
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if(errno)
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return 1;
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else if(n != 4)
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return 2;
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}
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}
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else {
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return 1;
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}
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/* check for the fLaC signature */
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if(0 == memcmp(FLAC__STREAM_SYNC_STRING, buffer, FLAC__STREAM_SYNC_LENGTH))
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return 0;
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else
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return 2;
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}
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FLAC__bool simple_iterator_copy_file_prefix_(FLAC__MetaData_SimpleIterator *iterator, FILE **tempfile, char **tempfilename, FLAC__bool append)
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@@ -2572,6 +2608,8 @@ FLAC__MetaData_ChainStatus get_equivalent_status_(FLAC__MetaData_SimpleIteratorS
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return FLAC__METADATA_CHAIN_STATUS_NOT_A_FLAC_FILE;
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case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_NOT_WRITABLE:
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return FLAC__METADATA_CHAIN_STATUS_NOT_WRITABLE;
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case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_BAD_METADATA:
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return FLAC__METADATA_CHAIN_STATUS_BAD_METADATA;
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case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_READ_ERROR:
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return FLAC__METADATA_CHAIN_STATUS_READ_ERROR;
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case FLAC__METADATA_SIMPLE_ITERATOR_STATUS_SEEK_ERROR:
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@@ -2589,3 +2627,249 @@ FLAC__MetaData_ChainStatus get_equivalent_status_(FLAC__MetaData_SimpleIteratorS
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return FLAC__METADATA_CHAIN_STATUS_INTERNAL_ERROR;
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}
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}
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#if 0
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
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FLAC__bool list(FILE *f, FLAC__bool verbose)
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{
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FLAC__byte buf[65536];
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FLAC__byte *b = buf;
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FLAC__StreamMetaData metadata;
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unsigned blocknum = 0, byte_offset = 0, i;
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/* skip any id3v2 tag */
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if(fread(buf, 1, 4, f) < 4) {
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fprintf(stderr, "ERROR: not a FLAC file\n");
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return false;
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}
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if(0 == memcmp(buf, "ID3", 3)) {
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unsigned tag_length = 0;
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/* skip to the tag length */
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if(fseek(f, 2, SEEK_CUR) < 0) {
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fprintf(stderr, "ERROR: bad ID3v2 tag\n");
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return false;
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}
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/* read the length */
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for(i = 0; i < 4; i++) {
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if(fread(buf, 1, 1, f) < 1 || buf[0] & 0x80) {
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fprintf(stderr, "ERROR: bad ID3v2 tag\n");
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return false;
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}
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tag_length <<= 7;
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tag_length |= (buf[0] & 0x7f);
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}
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/* skip the rest of the tag */
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if(fseek(f, tag_length, SEEK_CUR) < 0) {
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fprintf(stderr, "ERROR: bad ID3v2 tag\n");
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return false;
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}
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/* read the stream sync code */
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if(fread(buf, 1, 4, f) < 4) {
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fprintf(stderr, "ERROR: not a FLAC file (no '%s' header)\n", sync_string_);
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return false;
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}
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}
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/* check the stream sync code */
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if(memcmp(buf, sync_string_, 4)) {
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fprintf(stderr, "ERROR: not a FLAC file (no '%s' header)\n", sync_string_);
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return false;
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}
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byte_offset += 4;
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/* read the metadata blocks */
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do {
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/* read the metadata block header */
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if(fread(buf, 1, 4, f) < 4) {
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fprintf(stderr, "ERROR: short count reading metadata block header\n");
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return false;
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}
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metadata.is_last = (buf[0] & 0x80)? true:false;
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metadata.type = (FLAC__MetaDataType)(buf[0] & 0x7f);
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metadata.length = unpack_uint32(buf+1, 3);
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/* print header */
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printf("METADATA block #%u\n", blocknum);
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printf(" byte offset: %u\n", byte_offset);
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printf(" type: %u (%s)\n", (unsigned)metadata.type, metadata.type<=FLAC__METADATA_TYPE_SEEKTABLE? metadata_type_string_[metadata.type] : "UNKNOWN");
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printf(" is last: %s\n", metadata.is_last? "true":"false");
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printf(" length: %u\n", metadata.length);
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if(metadata.length > sizeof(buf)) {
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printf(" SKIPPING large block\n");
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if(fseek(f, metadata.length, SEEK_CUR) < 0) {
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fprintf(stderr, "ERROR: short count skipping metadata block data\n");
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return false;
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}
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continue;
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}
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/* read the metadata block data */
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if(fread(buf, 1, metadata.length, f) < metadata.length) {
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fprintf(stderr, "ERROR: short count reading metadata block data\n");
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return false;
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}
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switch(metadata.type) {
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case FLAC__METADATA_TYPE_STREAMINFO:
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b = buf;
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metadata.data.stream_info.min_blocksize = unpack_uint32(b, 2); b += 2;
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metadata.data.stream_info.max_blocksize = unpack_uint32(b, 2); b += 2;
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metadata.data.stream_info.min_framesize = unpack_uint32(b, 3); b += 3;
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metadata.data.stream_info.max_framesize = unpack_uint32(b, 3); b += 3;
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metadata.data.stream_info.sample_rate = (unpack_uint32(b, 2) << 4) | ((unsigned)(b[2] & 0xf0) >> 4);
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metadata.data.stream_info.channels = (unsigned)((b[2] & 0x0e) >> 1) + 1;
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metadata.data.stream_info.bits_per_sample = ((((unsigned)(b[2] & 0x01)) << 1) | (((unsigned)(b[3] & 0xf0)) >> 4)) + 1;
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metadata.data.stream_info.total_samples = (((FLAC__uint64)(b[3] & 0x0f)) << 32) | unpack_uint64(b+4, 4);
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memcpy(metadata.data.stream_info.md5sum, b+8, 16);
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break;
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case FLAC__METADATA_TYPE_PADDING:
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if(verbose) {
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/* dump contents */
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}
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break;
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case FLAC__METADATA_TYPE_APPLICATION:
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memcpy(metadata.data.application.id, buf, 4);
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metadata.data.application.data = buf+4;
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break;
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case FLAC__METADATA_TYPE_SEEKTABLE:
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metadata.data.seek_table.num_points = metadata.length / SEEKPOINT_LEN_;
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b = buf; /* we leave the points in buf for printing later */
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break;
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default:
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printf("SKIPPING block of unknown type\n");
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continue;
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}
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/* print data */
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switch(metadata.type) {
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case FLAC__METADATA_TYPE_STREAMINFO:
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printf(" minumum blocksize: %u samples\n", metadata.data.stream_info.min_blocksize);
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printf(" maximum blocksize: %u samples\n", metadata.data.stream_info.max_blocksize);
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printf(" minimum framesize: %u bytes\n", metadata.data.stream_info.min_framesize);
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printf(" maximum framesize: %u bytes\n", metadata.data.stream_info.max_framesize);
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printf(" sample_rate: %u Hz\n", metadata.data.stream_info.sample_rate);
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printf(" channels: %u\n", metadata.data.stream_info.channels);
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printf(" bits-per-sample: %u\n", metadata.data.stream_info.bits_per_sample);
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printf(" total samples: %llu\n", metadata.data.stream_info.total_samples);
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printf(" MD5 signature: ");
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for(i = 0; i < 16; i++)
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printf("%02x", metadata.data.stream_info.md5sum[i]);
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printf("\n");
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break;
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case FLAC__METADATA_TYPE_PADDING:
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if(verbose) {
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printf(" pad contents:\n");
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hexdump(buf, metadata.length, " ");
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}
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break;
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case FLAC__METADATA_TYPE_APPLICATION:
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printf(" application ID: ");
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for(i = 0; i < 4; i++)
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printf("%02x", metadata.data.application.id[i]);
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printf("\n");
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if(verbose) {
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printf(" data contents:\n");
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hexdump(metadata.data.application.data, metadata.length, " ");
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}
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break;
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case FLAC__METADATA_TYPE_SEEKTABLE:
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printf(" seek points: %u\n", metadata.data.seek_table.num_points);
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if(verbose) {
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for(i = 0; i < metadata.data.seek_table.num_points; i++, b += SEEKPOINT_LEN_)
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printf(" point %d: sample_number=%llu, stream_offset=%llu, frame_samples=%u\n", i, unpack_uint64(b, 8), unpack_uint64(b+8, 8), unpack_uint32(b+16, 2));
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}
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break;
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default:
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FLAC__ASSERT(0);
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}
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blocknum++;
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byte_offset += (4 + metadata.length);
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} while (!metadata.is_last);
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return true;
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}
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FLAC__uint32 unpack_uint32(FLAC__byte *b, unsigned bytes)
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{
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FLAC__uint32 ret = 0;
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unsigned i;
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for(i = 0; i < bytes; i++)
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ret = (ret << 8) | (FLAC__uint32)(*b++);
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return ret;
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}
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FLAC__uint64 unpack_uint64(FLAC__byte *b, unsigned bytes)
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{
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FLAC__uint64 ret = 0;
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unsigned i;
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for(i = 0; i < bytes; i++)
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ret = (ret << 8) | (FLAC__uint64)(*b++);
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return ret;
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}
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void hexdump(const FLAC__byte *buf, unsigned bytes, const char *indent)
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{
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unsigned i, left = bytes;
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const FLAC__byte *b = buf;
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for(i = 0; i < bytes; i += 16) {
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printf("%s%08X: "
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"%02X %02X %02X %02X %02X %02X %02X %02X "
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"%02X %02X %02X %02X %02X %02X %02X %02X "
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"%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c\n",
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indent, i,
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left > 0? (unsigned char)b[ 0] : 0,
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left > 1? (unsigned char)b[ 1] : 0,
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left > 2? (unsigned char)b[ 2] : 0,
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left > 3? (unsigned char)b[ 3] : 0,
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left > 4? (unsigned char)b[ 4] : 0,
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left > 5? (unsigned char)b[ 5] : 0,
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left > 6? (unsigned char)b[ 6] : 0,
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left > 7? (unsigned char)b[ 7] : 0,
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left > 8? (unsigned char)b[ 8] : 0,
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left > 9? (unsigned char)b[ 9] : 0,
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left > 10? (unsigned char)b[10] : 0,
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left > 11? (unsigned char)b[11] : 0,
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||||
left > 12? (unsigned char)b[12] : 0,
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||||
left > 13? (unsigned char)b[13] : 0,
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||||
left > 14? (unsigned char)b[14] : 0,
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left > 15? (unsigned char)b[15] : 0,
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(left > 0) ? (isprint(b[ 0]) ? b[ 0] : '.') : ' ',
|
||||
(left > 1) ? (isprint(b[ 1]) ? b[ 1] : '.') : ' ',
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||||
(left > 2) ? (isprint(b[ 2]) ? b[ 2] : '.') : ' ',
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||||
(left > 3) ? (isprint(b[ 3]) ? b[ 3] : '.') : ' ',
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||||
(left > 4) ? (isprint(b[ 4]) ? b[ 4] : '.') : ' ',
|
||||
(left > 5) ? (isprint(b[ 5]) ? b[ 5] : '.') : ' ',
|
||||
(left > 6) ? (isprint(b[ 6]) ? b[ 6] : '.') : ' ',
|
||||
(left > 7) ? (isprint(b[ 7]) ? b[ 7] : '.') : ' ',
|
||||
(left > 8) ? (isprint(b[ 8]) ? b[ 8] : '.') : ' ',
|
||||
(left > 9) ? (isprint(b[ 9]) ? b[ 9] : '.') : ' ',
|
||||
(left > 10) ? (isprint(b[10]) ? b[10] : '.') : ' ',
|
||||
(left > 11) ? (isprint(b[11]) ? b[11] : '.') : ' ',
|
||||
(left > 12) ? (isprint(b[12]) ? b[12] : '.') : ' ',
|
||||
(left > 13) ? (isprint(b[13]) ? b[13] : '.') : ' ',
|
||||
(left > 14) ? (isprint(b[14]) ? b[14] : '.') : ' ',
|
||||
(left > 15) ? (isprint(b[15]) ? b[15] : '.') : ' '
|
||||
);
|
||||
left -= 16;
|
||||
b += 16;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
Reference in New Issue
Block a user