FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/bitstream.c	Lines:	123	138	89.1 %
Date:	2020-07-11 02:49:52	Branches:	146	186	78.5 %


/*
 * Common bit i/o utils
 * Copyright (c) 2000, 2001 Fabrice Bellard
 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
 * Copyright (c) 2010 Loren Merritt
 *
 * alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * bitstream api.
 */

#include "libavutil/avassert.h"
#include "libavutil/qsort.h"
#include "avcodec.h"
#include "internal.h"
#include "mathops.h"
#include "put_bits.h"
#include "vlc.h"

const uint8_t ff_log2_run[41]={
 0, 0, 0, 0, 1, 1, 1, 1,
 2, 2, 2, 2, 3, 3, 3, 3,
 4, 4, 5, 5, 6, 6, 7, 7,
 8, 9,10,11,12,13,14,15,
16,17,18,19,20,21,22,23,
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)
{
    while (*string) {
        put_bits(pb, 8, *string);
        string++;
    }
    if (terminate_string)
        put_bits(pb, 8, 0);
}

void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length)
{
    int words = length >> 4;
    int bits  = length & 15;
    int i;

    if (length == 0)
        return;

    av_assert0(length <= put_bits_left(pb));

    if (CONFIG_SMALL || words < 16 || put_bits_count(pb) & 7) {
        for (i = 0; i < words; i++)
            put_bits(pb, 16, AV_RB16(src + 2 * i));
    } else {
        for (i = 0; put_bits_count(pb) & 31; i++)
            put_bits(pb, 8, src[i]);
        flush_put_bits(pb);
        memcpy(put_bits_ptr(pb), src + i, 2 * words - i);
        skip_put_bytes(pb, 2 * words - i);
    }

    put_bits(pb, bits, AV_RB16(src + 2 * words) >> (16 - bits));
}

/* VLC decoding */

#define GET_DATA(v, table, i, wrap, size)                   \
{                                                           \
    const uint8_t *ptr = (const uint8_t *)table + i * wrap; \
    switch(size) {                                          \
    case 1:                                                 \
        v = *(const uint8_t *)ptr;                          \
        break;                                              \
    case 2:                                                 \
        v = *(const uint16_t *)ptr;                         \
        break;                                              \
    case 4:                                                 \
        v = *(const uint32_t *)ptr;                         \
        break;                                              \
    default:                                                \
        av_assert1(0);                                      \
    }                                                       \
}


static int alloc_table(VLC *vlc, int size, int use_static)
{
    int index = vlc->table_size;

    vlc->table_size += size;
    if (vlc->table_size > vlc->table_allocated) {
        if (use_static)
            abort(); // cannot do anything, init_vlc() is used with too little memory
        vlc->table_allocated += (1 << vlc->bits);
        vlc->table = av_realloc_f(vlc->table, vlc->table_allocated, sizeof(VLC_TYPE) * 2);
        if (!vlc->table) {
            vlc->table_allocated = 0;
            vlc->table_size = 0;
            return AVERROR(ENOMEM);
        }
        memset(vlc->table + vlc->table_allocated - (1 << vlc->bits), 0, sizeof(VLC_TYPE) * 2 << vlc->bits);
    }
    return index;
}

typedef struct VLCcode {
    uint8_t bits;
    uint16_t 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 compare_vlcspec(const void *a, const void *b)
{
    const VLCcode *sa = a, *sb = b;
    return (sa->code >> 1) - (sb->code >> 1);
}
/**
 * Build VLC decoding tables suitable for use with get_vlc().
 *
 * @param vlc            the context to be initialized
 *
 * @param table_nb_bits  max length of vlc codes to store directly in this table
 *                       (Longer codes are delegated to subtables.)
 *
 * @param nb_codes       number of elements in codes[]
 *
 * @param codes          descriptions of the vlc codes
 *                       These must be ordered such that codes going into the same subtable are contiguous.
 *                       Sorting by VLCcode.code is sufficient, though not necessary.
 */
static int build_table(VLC *vlc, int table_nb_bits, int nb_codes,
                       VLCcode *codes, int flags)
{
    int table_size, table_index, index, code_prefix, symbol, subtable_bits;
    int i, j, k, n, nb, inc;
    uint32_t code;
    volatile VLC_TYPE (* volatile table)[2]; // the double volatile is needed to prevent an internal compiler error in gcc 4.2

    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)
        return table_index;
    table = (volatile VLC_TYPE (*)[2])&vlc->table[table_index];

    /* first pass: map codes and compute auxiliary table sizes */
    for (i = 0; i < nb_codes; i++) {
        n      = codes[i].bits;
        code   = codes[i].code;
        symbol = codes[i].symbol;
        ff_dlog(NULL, "i=%d n=%d code=0x%"PRIx32"\n", i, n, code);
        if (n <= table_nb_bits) {
            /* no need to add another table */
            j = code >> (32 - table_nb_bits);
            nb = 1 << (table_nb_bits - n);
            inc = 1;
            if (flags & INIT_VLC_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 || oldsym) && (bits != n || oldsym != symbol)) {
                    av_log(NULL, AV_LOG_ERROR, "incorrect codes\n");
                    return AVERROR_INVALIDDATA;
                }
                table[j][1] = n; //bits
                table[j][0] = symbol;
                j += inc;
            }
        } else {
            /* fill auxiliary table recursively */
            n -= table_nb_bits;
            code_prefix = code >> (32 - table_nb_bits);
            subtable_bits = n;
            codes[i].bits = n;
            codes[i].code = code << table_nb_bits;
            for (k = i+1; k < nb_codes; k++) {
                n = codes[k].bits - table_nb_bits;
                if (n <= 0)
                    break;
                code = codes[k].code;
                if (code >> (32 - table_nb_bits) != code_prefix)
                    break;
                codes[k].bits = n;
                codes[k].code = code << table_nb_bits;
                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;
            table[j][1] = -subtable_bits;
            ff_dlog(NULL, "%4x: n=%d (subtable)\n",
                    j, codes[i].bits + table_nb_bits);
            index = build_table(vlc, subtable_bits, k-i, codes+i, flags);
            if (index < 0)
                return index;
            /* 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;
        }
    }

    for (i = 0; i < table_size; i++) {
        if (table[i][1] == 0) //bits
            table[i][0] = -1; //codes
    }

    return table_index;
}


/* Build VLC decoding tables suitable for use with get_vlc().

   'nb_bits' sets the decoding table size (2^nb_bits) entries. The
   bigger it is, the faster is the decoding. But it should not be too
   big to save memory and L1 cache. '9' is a good compromise.

   'nb_codes' : number of vlcs codes

   'bits' : table which gives the size (in bits) of each vlc code.

   'codes' : table which gives the bit pattern of of each vlc code.

   'symbols' : table which gives the values to be returned from get_vlc().

   'xxx_wrap' : give the number of bytes between each entry of the
   'bits' or 'codes' tables.

   'xxx_size' : gives the number of bytes of each entry of the 'bits'
   or 'codes' tables. Currently 1,2 and 4 are supported.

   '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,
                       const void *codes, int codes_wrap, int codes_size,
                       const void *symbols, int symbols_wrap, int symbols_size,
                       int flags)
{
    VLCcode *buf;
    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));
        localvlc = *vlc_arg;
        vlc = &localvlc;
        vlc->table_size = 0;
    } else {
        vlc->table           = NULL;
        vlc->table_allocated = 0;
        vlc->table_size      = 0;
    }
    if (nb_codes + 1 > FF_ARRAY_ELEMS(localbuf)) {
        buf = av_malloc_array((nb_codes + 1), sizeof(VLCcode));
        if (!buf)
            return AVERROR(ENOMEM);
    } else
        buf = localbuf;


    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);               \
        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 (buf != localbuf)                                            \
                av_free(buf);                                               \
            return AVERROR(EINVAL);                                         \
        }                                                                   \
        GET_DATA(buf[j].code, codes, i, codes_wrap, codes_size);            \
        if (buf[j].code >= (1LL<<buf[j].bits)) {                            \
            av_log(NULL, AV_LOG_ERROR, "Invalid code %"PRIx32" for %d in "  \
                   "init_vlc\n", buf[j].code, i);                           \
            if (buf != localbuf)                                            \
                av_free(buf);                                               \
            return AVERROR(EINVAL);                                         \
        }                                                                   \
        if (flags & INIT_VLC_LE)                                            \
            buf[j].code = bitswap_32(buf[j].code);                          \
        else                                                                \
            buf[j].code <<= 32 - buf[j].bits;                               \
        if (symbols)                                                        \
            GET_DATA(buf[j].symbol, symbols, i, symbols_wrap, symbols_size) \
        else                                                                \
            buf[j].symbol = i;                                              \
        j++;                                                                \
    }
    COPY(buf[j].bits > 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);
    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);

        av_assert0(ret >= 0);
        *vlc_arg = *vlc;
    } else {
        if (buf != localbuf)
            av_free(buf);
        if (ret < 0) {
            av_freep(&vlc->table);
            return ret;
        }
    }
    return 0;
}


void ff_free_vlc(VLC *vlc)
{
    av_freep(&vlc->table);
}


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* Common bit i/o utils
3			* Copyright (c) 2000, 2001 Fabrice Bellard
4			* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5			* Copyright (c) 2010 Loren Merritt
6			*
7			* alternative bitstream reader & writer by Michael Niedermayer <michaelni@gmx.at>
8			*
9			* This file is part of FFmpeg.
10			*
11			* FFmpeg is free software; you can redistribute it and/or
12			* modify it under the terms of the GNU Lesser General Public
13			* License as published by the Free Software Foundation; either
14			* version 2.1 of the License, or (at your option) any later version.
15			*
16			* FFmpeg is distributed in the hope that it will be useful,
17			* but WITHOUT ANY WARRANTY; without even the implied warranty of
18			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19			* Lesser General Public License for more details.
20			*
21			* You should have received a copy of the GNU Lesser General Public
22			* License along with FFmpeg; if not, write to the Free Software
23			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24			*/
25
26			/**
27			* @file
28			* bitstream api.
29			*/
30
31			#include "libavutil/avassert.h"
32			#include "libavutil/qsort.h"
33			#include "avcodec.h"
34			#include "internal.h"
35			#include "mathops.h"
36			#include "put_bits.h"
37			#include "vlc.h"
38
39			const uint8_t ff_log2_run[41]={
40			0, 0, 0, 0, 1, 1, 1, 1,
41			2, 2, 2, 2, 3, 3, 3, 3,
42			4, 4, 5, 5, 6, 6, 7, 7,
43			8, 9,10,11,12,13,14,15,
44			16,17,18,19,20,21,22,23,
45			24,
46			};
47
48		703171	void avpriv_align_put_bits(PutBitContext *s)
49			{
50		703171	put_bits(s, s->bit_left & 7, 0);
51		703171	}
52
53		1025	void avpriv_put_string(PutBitContext pb, const char string,
54			int terminate_string)
55			{
56	✓✓	6125	while (*string) {
57		5100	put_bits(pb, 8, *string);
58		5100	string++;
59			}
60	✓✓	1025	if (terminate_string)
61		365	put_bits(pb, 8, 0);
62		1025	}
63
64		1232579	void avpriv_copy_bits(PutBitContext pb, const uint8_t src, int length)
65			{
66		1232579	int words = length >> 4;
67		1232579	int bits = length & 15;
68			int i;
69
70	✓✓	1232579	if (length == 0)
71		114010	return;
72
73	✗✓	1118569	av_assert0(length <= put_bits_left(pb));
74
75	✓✓✓✓	1118569	if (CONFIG_SMALL \|\| words < 16 \|\| put_bits_count(pb) & 7) {
76	✓✓	7800573	for (i = 0; i < words; i++)
77		6696778	put_bits(pb, 16, AV_RB16(src + 2 * i));
78			} else {
79	✓✓	35902	for (i = 0; put_bits_count(pb) & 31; i++)
80		21128	put_bits(pb, 8, src[i]);
81		14774	flush_put_bits(pb);
82		14774	memcpy(put_bits_ptr(pb), src + i, 2 * words - i);
83		14774	skip_put_bytes(pb, 2 * words - i);
84			}
85
86		1118569	put_bits(pb, bits, AV_RB16(src + 2 * words) >> (16 - bits));
87			}
88
89			/* VLC decoding */
90
91			#define GET_DATA(v, table, i, wrap, size) \
92			{ \
93			const uint8_t ptr = (const uint8_t )table + i * wrap; \
94			switch(size) { \
95			case 1: \
96			v = (const uint8_t )ptr; \
97			break; \
98			case 2: \
99			v = (const uint16_t )ptr; \
100			break; \
101			case 4: \
102			v = (const uint32_t )ptr; \
103			break; \
104			default: \
105			av_assert1(0); \
106			} \
107			}
108
109
110		443819	static int alloc_table(VLC *vlc, int size, int use_static)
111			{
112		443819	int index = vlc->table_size;
113
114		443819	vlc->table_size += size;
115	✓✓	443819	if (vlc->table_size > vlc->table_allocated) {
116	✗✓	53853	if (use_static)
117			abort(); // cannot do anything, init_vlc() is used with too little memory
118		53853	vlc->table_allocated += (1 << vlc->bits);
119		53853	vlc->table = av_realloc_f(vlc->table, vlc->table_allocated, sizeof(VLC_TYPE) * 2);
120	✗✓	53853	if (!vlc->table) {
121			vlc->table_allocated = 0;
122			vlc->table_size = 0;
123			return AVERROR(ENOMEM);
124			}
125		53853	memset(vlc->table + vlc->table_allocated - (1 << vlc->bits), 0, sizeof(VLC_TYPE) * 2 << vlc->bits);
126			}
127		443819	return index;
128			}
129
130			typedef struct VLCcode {
131			uint8_t bits;
132			uint16_t symbol;
133			/** codeword, with the first bit-to-be-read in the msb
134			* (even if intended for a little-endian bitstream reader) */
135			uint32_t code;
136			} VLCcode;
137
138		26112512	static int compare_vlcspec(const void a, const void b)
139			{
140		26112512	const VLCcode sa = a, sb = b;
141		26112512	return (sa->code >> 1) - (sb->code >> 1);
142			}
143			/**
144			* Build VLC decoding tables suitable for use with get_vlc().
145			*
146			* @param vlc the context to be initialized
147			*
148			* @param table_nb_bits max length of vlc codes to store directly in this table
149			* (Longer codes are delegated to subtables.)
150			*
151			* @param nb_codes number of elements in codes[]
152			*
153			* @param codes descriptions of the vlc codes
154			* These must be ordered such that codes going into the same subtable are contiguous.
155			* Sorting by VLCcode.code is sufficient, though not necessary.
156			*/
157		443819	static int build_table(VLC *vlc, int table_nb_bits, int nb_codes,
158			VLCcode *codes, int flags)
159			{
160			int table_size, table_index, index, code_prefix, symbol, subtable_bits;
161			int i, j, k, n, nb, inc;
162			uint32_t code;
163			volatile VLC_TYPE (* volatile table)[2]; // the double volatile is needed to prevent an internal compiler error in gcc 4.2
164
165	✗✓	443819	if (table_nb_bits > 30)
166			return AVERROR(EINVAL);
167		443819	table_size = 1 << table_nb_bits;
168		443819	table_index = alloc_table(vlc, table_size, flags & INIT_VLC_USE_NEW_STATIC);
169			ff_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size);
170	✗✓	443819	if (table_index < 0)
171			return table_index;
172		443819	table = (volatile VLC_TYPE (*)[2])&vlc->table[table_index];
173
174			/* first pass: map codes and compute auxiliary table sizes */
175	✓✓	5495015	for (i = 0; i < nb_codes; i++) {
176		5051196	n = codes[i].bits;
177		5051196	code = codes[i].code;
178		5051196	symbol = codes[i].symbol;
179			ff_dlog(NULL, "i=%d n=%d code=0x%"PRIx32"\n", i, n, code);
180	✓✓	5051196	if (n <= table_nb_bits) {
181			/* no need to add another table */
182		4668385	j = code >> (32 - table_nb_bits);
183		4668385	nb = 1 << (table_nb_bits - n);
184		4668385	inc = 1;
185	✓✓	4668385	if (flags & INIT_VLC_LE) {
186		451513	j = bitswap_32(code);
187		451513	inc = 1 << n;
188			}
189	✓✓	46890039	for (k = 0; k < nb; k++) {
190		42221654	int bits = table[j][1];
191		42221654	int oldsym = table[j][0];
192			ff_dlog(NULL, "%4x: code=%d n=%d\n", j, i, n);
193	✓✓✗✓ ✓✗✗✓	42221654	if ((bits \|\| oldsym) && (bits != n \|\| oldsym != symbol)) {
194			av_log(NULL, AV_LOG_ERROR, "incorrect codes\n");
195			return AVERROR_INVALIDDATA;
196			}
197		42221654	table[j][1] = n; //bits
198		42221654	table[j][0] = symbol;
199		42221654	j += inc;
200			}
201			} else {
202			/* fill auxiliary table recursively */
203		382811	n -= table_nb_bits;
204		382811	code_prefix = code >> (32 - table_nb_bits);
205		382811	subtable_bits = n;
206		382811	codes[i].bits = n;
207		382811	codes[i].code = code << table_nb_bits;
208	✓✓	3470083	for (k = i+1; k < nb_codes; k++) {
209		3468682	n = codes[k].bits - table_nb_bits;
210	✓✓	3468682	if (n <= 0)
211		44711	break;
212		3423971	code = codes[k].code;
213	✓✓	3423971	if (code >> (32 - table_nb_bits) != code_prefix)
214		336699	break;
215		3087272	codes[k].bits = n;
216		3087272	codes[k].code = code << table_nb_bits;
217		3087272	subtable_bits = FFMAX(subtable_bits, n);
218			}
219		382811	subtable_bits = FFMIN(subtable_bits, table_nb_bits);
220	✓✓	382811	j = (flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix;
221		382811	table[j][1] = -subtable_bits;
222			ff_dlog(NULL, "%4x: n=%d (subtable)\n",
223			j, codes[i].bits + table_nb_bits);
224		382811	index = build_table(vlc, subtable_bits, k-i, codes+i, flags);
225	✗✓	382811	if (index < 0)
226			return index;
227			/* note: realloc has been done, so reload tables */
228		382811	table = (volatile VLC_TYPE (*)[2])&vlc->table[table_index];
229		382811	table[j][0] = index; //code
230	✗✓	382811	if (table[j][0] != index) {
231			avpriv_request_sample(NULL, "strange codes");
232			return AVERROR_PATCHWELCOME;
233			}
234		382811	i = k-1;
235			}
236			}
237
238	✓✓	43568567	for (i = 0; i < table_size; i++) {
239	✓✓	43124748	if (table[i][1] == 0) //bits
240		520283	table[i][0] = -1; //codes
241			}
242
243		443819	return table_index;
244			}
245
246
247			/* Build VLC decoding tables suitable for use with get_vlc().
248
249			'nb_bits' sets the decoding table size (2^nb_bits) entries. The
250			bigger it is, the faster is the decoding. But it should not be too
251			big to save memory and L1 cache. '9' is a good compromise.
252
253			'nb_codes' : number of vlcs codes
254
255			'bits' : table which gives the size (in bits) of each vlc code.
256
257			'codes' : table which gives the bit pattern of of each vlc code.
258
259			'symbols' : table which gives the values to be returned from get_vlc().
260
261			'xxx_wrap' : give the number of bytes between each entry of the
262			'bits' or 'codes' tables.
263
264			'xxx_size' : gives the number of bytes of each entry of the 'bits'
265			or 'codes' tables. Currently 1,2 and 4 are supported.
266
267			'wrap' and 'size' make it possible to use any memory configuration and types
268			(byte/word/long) to store the 'bits', 'codes', and 'symbols' tables.
269
270			'use_static' should be set to 1 for tables, which should be freed
271			with av_free_static(), 0 if ff_free_vlc() will be used.
272			*/
273		61008	int ff_init_vlc_sparse(VLC *vlc_arg, int nb_bits, int nb_codes,
274			const void *bits, int bits_wrap, int bits_size,
275			const void *codes, int codes_wrap, int codes_size,
276			const void *symbols, int symbols_wrap, int symbols_size,
277			int flags)
278			{
279			VLCcode *buf;
280			int i, j, ret;
281			VLCcode localbuf[1500]; // the maximum currently needed is 1296 by rv34
282			VLC localvlc, *vlc;
283
284		61008	vlc = vlc_arg;
285		61008	vlc->bits = nb_bits;
286	✓✓	61008	if (flags & INIT_VLC_USE_NEW_STATIC) {
287	✗✓	32040	av_assert0(nb_codes + 1 <= FF_ARRAY_ELEMS(localbuf));
288		32040	localvlc = *vlc_arg;
289		32040	vlc = &localvlc;
290		32040	vlc->table_size = 0;
291			} else {
292		28968	vlc->table = NULL;
293		28968	vlc->table_allocated = 0;
294		28968	vlc->table_size = 0;
295			}
296	✓✓	61008	if (nb_codes + 1 > FF_ARRAY_ELEMS(localbuf)) {
297		120	buf = av_malloc_array((nb_codes + 1), sizeof(VLCcode));
298	✗✓	120	if (!buf)
299			return AVERROR(ENOMEM);
300			} else
301		60888	buf = localbuf;
302
303
304	✗✓✗✗	61008	av_assert0(symbols_size <= 2 \|\| !symbols);
305		61008	j = 0;
306			#define COPY(condition)\
307			for (i = 0; i < nb_codes; i++) { \
308			GET_DATA(buf[j].bits, bits, i, bits_wrap, bits_size); \
309			if (!(condition)) \
310			continue; \
311			if (buf[j].bits > 3*nb_bits \|\| buf[j].bits>32) { \
312			av_log(NULL, AV_LOG_ERROR, "Too long VLC (%d) in init_vlc\n", buf[j].bits);\
313			if (buf != localbuf) \
314			av_free(buf); \
315			return AVERROR(EINVAL); \
316			} \
317			GET_DATA(buf[j].code, codes, i, codes_wrap, codes_size); \
318			if (buf[j].code >= (1LL<<buf[j].bits)) { \
319			av_log(NULL, AV_LOG_ERROR, "Invalid code %"PRIx32" for %d in " \
320			"init_vlc\n", buf[j].code, i); \
321			if (buf != localbuf) \
322			av_free(buf); \
323			return AVERROR(EINVAL); \
324			} \
325			if (flags & INIT_VLC_LE) \
326			buf[j].code = bitswap_32(buf[j].code); \
327			else \
328			buf[j].code <<= 32 - buf[j].bits; \
329			if (symbols) \
330			GET_DATA(buf[j].symbol, symbols, i, symbols_wrap, symbols_size) \
331			else \
332			buf[j].symbol = i; \
333			j++; \
334			}
335	✓✓✓✗ ✓✓✓✗ ✗✓✗✗ ✓✓✓✗ ✗✓✗✗ ✓✓✓✓ ✓✓✗✗ ✓✓	6786228	COPY(buf[j].bits > nb_bits);
336			// qsort is the slowest part of init_vlc, and could probably be improved or avoided
337	✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓ ✓✓✓✓	21815436	AV_QSORT(buf, j, struct VLCcode, compare_vlcspec);
338	✓✓✓✗ ✓✓✓✓ ✓✗✗✓ ✗✗✓✓ ✓✗✗✓ ✗✗✓✓ ✓✓✓✓ ✗✗✓✓	6786228	COPY(buf[j].bits && buf[j].bits <= nb_bits);
339		61008	nb_codes = j;
340
341		61008	ret = build_table(vlc, nb_bits, nb_codes, buf, flags);
342
343	✓✓	61008	if (flags & INIT_VLC_USE_NEW_STATIC) {
344	✗✓	32040	if(vlc->table_size != vlc->table_allocated)
345			av_log(NULL, AV_LOG_ERROR, "needed %d had %d\n", vlc->table_size, vlc->table_allocated);
346
347	✗✓	32040	av_assert0(ret >= 0);
348		32040	vlc_arg = vlc;
349			} else {
350	✓✓	28968	if (buf != localbuf)
351		120	av_free(buf);
352	✗✓	28968	if (ret < 0) {
353			av_freep(&vlc->table);
354			return ret;
355			}
356			}
357		61008	return 0;
358			}
359
360
361		31782	void ff_free_vlc(VLC *vlc)
362			{
363		31782	av_freep(&vlc->table);
364		31782	}