X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fbitstream.c;h=f0488cafd49c53e2c112e0018b587bcc965aacc2;hb=6e30b35b85b81c802e52a1078ec7a3097e353c6d;hp=8762e5f4b2fecf370af6256c63b530031a344838;hpb=34a0a9746b2f441db7c45983838a88aa87a33834;p=ffmpeg diff --git a/libavcodec/bitstream.c b/libavcodec/bitstream.c index 8762e5f4b2f..f0488cafd49 100644 --- a/libavcodec/bitstream.c +++ b/libavcodec/bitstream.c @@ -45,13 +45,7 @@ const uint8_t ff_log2_run[41]={ 24, }; -void avpriv_align_put_bits(PutBitContext *s) -{ - put_bits(s, s->bit_left & 7, 0); -} - -void avpriv_put_string(PutBitContext *pb, const char *string, - int terminate_string) +void ff_put_string(PutBitContext *pb, const char *string, int terminate_string) { while (*string) { put_bits(pb, 8, *string); @@ -61,7 +55,7 @@ void avpriv_put_string(PutBitContext *pb, const char *string, put_bits(pb, 8, 0); } -void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length) +void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length) { int words = length >> 4; int bits = length & 15; @@ -99,10 +93,10 @@ void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length) v = *(const uint16_t *)ptr; \ break; \ case 4: \ + default: \ + av_assert1(size == 4); \ v = *(const uint32_t *)ptr; \ break; \ - default: \ - av_assert1(0); \ } \ } @@ -127,14 +121,41 @@ static int alloc_table(VLC *vlc, int size, int use_static) return index; } +#define LOCALBUF_ELEMS 1500 // the maximum currently needed is 1296 by rv34 + typedef struct VLCcode { uint8_t bits; - uint16_t symbol; + VLC_TYPE symbol; /** codeword, with the first bit-to-be-read in the msb * (even if intended for a little-endian bitstream reader) */ uint32_t code; } VLCcode; +static int vlc_common_init(VLC *vlc_arg, int nb_bits, int nb_codes, + VLC **vlc, VLC *localvlc, VLCcode **buf, + int flags) +{ + *vlc = vlc_arg; + (*vlc)->bits = nb_bits; + if (flags & INIT_VLC_USE_NEW_STATIC) { + av_assert0(nb_codes <= LOCALBUF_ELEMS); + *localvlc = *vlc_arg; + *vlc = localvlc; + (*vlc)->table_size = 0; + } else { + (*vlc)->table = NULL; + (*vlc)->table_allocated = 0; + (*vlc)->table_size = 0; + } + if (nb_codes > LOCALBUF_ELEMS) { + *buf = av_malloc_array(nb_codes, sizeof(VLCcode)); + if (!*buf) + return AVERROR(ENOMEM); + } + + return 0; +} + static int compare_vlcspec(const void *a, const void *b) { const VLCcode *sa = a, *sb = b; @@ -162,9 +183,9 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, uint32_t code; volatile VLC_TYPE (* volatile table)[2]; // the double volatile is needed to prevent an internal compiler error in gcc 4.2 - table_size = 1 << table_nb_bits; if (table_nb_bits > 30) return AVERROR(EINVAL); + table_size = 1 << table_nb_bits; table_index = alloc_table(vlc, table_size, flags & INIT_VLC_USE_NEW_STATIC); ff_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size); if (table_index < 0) @@ -182,14 +203,15 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, j = code >> (32 - table_nb_bits); nb = 1 << (table_nb_bits - n); inc = 1; - if (flags & INIT_VLC_LE) { + if (flags & INIT_VLC_OUTPUT_LE) { j = bitswap_32(code); inc = 1 << n; } for (k = 0; k < nb; k++) { int bits = table[j][1]; + int oldsym = table[j][0]; ff_dlog(NULL, "%4x: code=%d n=%d\n", j, i, n); - if (bits != 0 && bits != n) { + if ((bits || oldsym) && (bits != n || oldsym != symbol)) { av_log(NULL, AV_LOG_ERROR, "incorrect codes\n"); return AVERROR_INVALIDDATA; } @@ -216,7 +238,7 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, subtable_bits = FFMAX(subtable_bits, n); } subtable_bits = FFMIN(subtable_bits, table_nb_bits); - j = (flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix; + j = (flags & INIT_VLC_OUTPUT_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix; table[j][1] = -subtable_bits; ff_dlog(NULL, "%4x: n=%d (subtable)\n", j, codes[i].bits + table_nb_bits); @@ -226,6 +248,10 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, /* note: realloc has been done, so reload tables */ table = (volatile VLC_TYPE (*)[2])&vlc->table[table_index]; table[j][0] = index; //code + if (table[j][0] != index) { + avpriv_request_sample(NULL, "strange codes"); + return AVERROR_PATCHWELCOME; + } i = k-1; } } @@ -238,6 +264,27 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, return table_index; } +static int vlc_common_end(VLC *vlc, int nb_bits, int nb_codes, VLCcode *codes, + int flags, VLC *vlc_arg, VLCcode localbuf[LOCALBUF_ELEMS]) +{ + int ret = build_table(vlc, nb_bits, nb_codes, codes, flags); + + if (flags & INIT_VLC_USE_NEW_STATIC) { + if (vlc->table_size != vlc->table_allocated && + !(flags & (INIT_VLC_STATIC_OVERLONG & ~INIT_VLC_USE_NEW_STATIC))) + av_log(NULL, AV_LOG_ERROR, "needed %d had %d\n", vlc->table_size, vlc->table_allocated); + av_assert0(ret >= 0); + *vlc_arg = *vlc; + } else { + if (codes != localbuf) + av_free(codes); + if (ret < 0) { + av_freep(&vlc->table); + return ret; + } + } + return 0; +} /* Build VLC decoding tables suitable for use with get_vlc(). @@ -261,9 +308,6 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, 'wrap' and 'size' make it possible to use any memory configuration and types (byte/word/long) to store the 'bits', 'codes', and 'symbols' tables. - - 'use_static' should be set to 1 for tables, which should be freed - with av_free_static(), 0 if ff_free_vlc() will be used. */ int ff_init_vlc_sparse(VLC *vlc_arg, int nb_bits, int nb_codes, const void *bits, int bits_wrap, int bits_size, @@ -271,52 +315,39 @@ int ff_init_vlc_sparse(VLC *vlc_arg, int nb_bits, int nb_codes, const void *symbols, int symbols_wrap, int symbols_size, int flags) { - VLCcode *buf; + VLCcode localbuf[LOCALBUF_ELEMS], *buf = localbuf; int i, j, ret; - VLCcode localbuf[1500]; // the maximum currently needed is 1296 by rv34 VLC localvlc, *vlc; - vlc = vlc_arg; - vlc->bits = nb_bits; - if (flags & INIT_VLC_USE_NEW_STATIC) { - av_assert0(nb_codes + 1 <= FF_ARRAY_ELEMS(localbuf)); - buf = localbuf; - localvlc = *vlc_arg; - vlc = &localvlc; - vlc->table_size = 0; - } else { - vlc->table = NULL; - vlc->table_allocated = 0; - vlc->table_size = 0; - - buf = av_malloc_array((nb_codes + 1), sizeof(VLCcode)); - if (!buf) - return AVERROR(ENOMEM); - } - + ret = vlc_common_init(vlc_arg, nb_bits, nb_codes, &vlc, &localvlc, + &buf, flags); + if (ret < 0) + return ret; av_assert0(symbols_size <= 2 || !symbols); j = 0; #define COPY(condition)\ for (i = 0; i < nb_codes; i++) { \ - GET_DATA(buf[j].bits, bits, i, bits_wrap, bits_size); \ + unsigned len; \ + GET_DATA(len, bits, i, bits_wrap, bits_size); \ if (!(condition)) \ continue; \ - if (buf[j].bits > 3*nb_bits || buf[j].bits>32) { \ - av_log(NULL, AV_LOG_ERROR, "Too long VLC (%d) in init_vlc\n", buf[j].bits);\ - if (!(flags & INIT_VLC_USE_NEW_STATIC)) \ + if (len > 3*nb_bits || len > 32) { \ + av_log(NULL, AV_LOG_ERROR, "Too long VLC (%u) in init_vlc\n", len);\ + if (buf != localbuf) \ av_free(buf); \ return AVERROR(EINVAL); \ } \ + buf[j].bits = len; \ GET_DATA(buf[j].code, codes, i, codes_wrap, codes_size); \ if (buf[j].code >= (1LL< nb_bits); + COPY(len > nb_bits); // qsort is the slowest part of init_vlc, and could probably be improved or avoided AV_QSORT(buf, j, struct VLCcode, compare_vlcspec); - COPY(buf[j].bits && buf[j].bits <= nb_bits); + COPY(len && len <= nb_bits); nb_codes = j; - ret = build_table(vlc, nb_bits, nb_codes, buf, flags); - - if (flags & INIT_VLC_USE_NEW_STATIC) { - if(vlc->table_size != vlc->table_allocated) - av_log(NULL, AV_LOG_ERROR, "needed %d had %d\n", vlc->table_size, vlc->table_allocated); + return vlc_common_end(vlc, nb_bits, nb_codes, buf, + flags, vlc_arg, localbuf); +} - av_assert0(ret >= 0); - *vlc_arg = *vlc; - } else { - av_free(buf); - if (ret < 0) { - av_freep(&vlc->table); - return ret; +int ff_init_vlc_from_lengths(VLC *vlc_arg, int nb_bits, int nb_codes, + const int8_t *lens, int lens_wrap, + const void *symbols, int symbols_wrap, int symbols_size, + int offset, int flags, void *logctx) +{ + VLCcode localbuf[LOCALBUF_ELEMS], *buf = localbuf; + VLC localvlc, *vlc; + uint64_t code; + int ret, j, len_max = FFMIN(32, 3 * nb_bits); + + ret = vlc_common_init(vlc_arg, nb_bits, nb_codes, &vlc, &localvlc, + &buf, flags); + if (ret < 0) + return ret; + + j = code = 0; + for (int i = 0; i < nb_codes; i++, lens += lens_wrap) { + int len = *lens; + if (len > 0) { + unsigned sym; + + buf[j].bits = len; + if (symbols) + GET_DATA(sym, symbols, i, symbols_wrap, symbols_size) + else + sym = i; + buf[j].symbol = sym + offset; + buf[j++].code = code; + } else if (len < 0) { + len = -len; + } else + continue; + if (len > len_max || code & ((1U << (32 - len)) - 1)) { + av_log(logctx, AV_LOG_ERROR, "Invalid VLC (length %u)\n", len); + goto fail; + } + code += 1U << (32 - len); + if (code > UINT32_MAX + 1ULL) { + av_log(logctx, AV_LOG_ERROR, "Overdetermined VLC tree\n"); + goto fail; } } - return 0; + return vlc_common_end(vlc, nb_bits, j, buf, + flags, vlc_arg, localbuf); +fail: + if (buf != localbuf) + av_free(buf); + return AVERROR_INVALIDDATA; } - void ff_free_vlc(VLC *vlc) { av_freep(&vlc->table);