diff options
Diffstat (limited to 'media/ffvpx/libavutil/lzo.c')
| -rw-r--r-- | media/ffvpx/libavutil/lzo.c | 205 |
1 files changed, 0 insertions, 205 deletions
diff --git a/media/ffvpx/libavutil/lzo.c b/media/ffvpx/libavutil/lzo.c deleted file mode 100644 index 1ae076e33..000000000 --- a/media/ffvpx/libavutil/lzo.c +++ /dev/null @@ -1,205 +0,0 @@ -/* - * LZO 1x decompression - * Copyright (c) 2006 Reimar Doeffinger - * - * 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 - */ - -#include <string.h> - -#include "avutil.h" -#include "avassert.h" -#include "common.h" -#include "intreadwrite.h" -#include "lzo.h" - -/// Define if we may write up to 12 bytes beyond the output buffer. -#define OUTBUF_PADDED 1 -/// Define if we may read up to 8 bytes beyond the input buffer. -#define INBUF_PADDED 1 - -typedef struct LZOContext { - const uint8_t *in, *in_end; - uint8_t *out_start, *out, *out_end; - int error; -} LZOContext; - -/** - * @brief Reads one byte from the input buffer, avoiding an overrun. - * @return byte read - */ -static inline int get_byte(LZOContext *c) -{ - if (c->in < c->in_end) - return *c->in++; - c->error |= AV_LZO_INPUT_DEPLETED; - return 1; -} - -#ifdef INBUF_PADDED -#define GETB(c) (*(c).in++) -#else -#define GETB(c) get_byte(&(c)) -#endif - -/** - * @brief Decodes a length value in the coding used by lzo. - * @param x previous byte value - * @param mask bits used from x - * @return decoded length value - */ -static inline int get_len(LZOContext *c, int x, int mask) -{ - int cnt = x & mask; - if (!cnt) { - while (!(x = get_byte(c))) { - if (cnt >= INT_MAX - 1000) { - c->error |= AV_LZO_ERROR; - break; - } - cnt += 255; - } - cnt += mask + x; - } - return cnt; -} - -/** - * @brief Copies bytes from input to output buffer with checking. - * @param cnt number of bytes to copy, must be >= 0 - */ -static inline void copy(LZOContext *c, int cnt) -{ - register const uint8_t *src = c->in; - register uint8_t *dst = c->out; - av_assert0(cnt >= 0); - if (cnt > c->in_end - src) { - cnt = FFMAX(c->in_end - src, 0); - c->error |= AV_LZO_INPUT_DEPLETED; - } - if (cnt > c->out_end - dst) { - cnt = FFMAX(c->out_end - dst, 0); - c->error |= AV_LZO_OUTPUT_FULL; - } -#if defined(INBUF_PADDED) && defined(OUTBUF_PADDED) - AV_COPY32U(dst, src); - src += 4; - dst += 4; - cnt -= 4; - if (cnt > 0) -#endif - memcpy(dst, src, cnt); - c->in = src + cnt; - c->out = dst + cnt; -} - -/** - * @brief Copies previously decoded bytes to current position. - * @param back how many bytes back we start, must be > 0 - * @param cnt number of bytes to copy, must be > 0 - * - * cnt > back is valid, this will copy the bytes we just copied, - * thus creating a repeating pattern with a period length of back. - */ -static inline void copy_backptr(LZOContext *c, int back, int cnt) -{ - register uint8_t *dst = c->out; - av_assert0(cnt > 0); - if (dst - c->out_start < back) { - c->error |= AV_LZO_INVALID_BACKPTR; - return; - } - if (cnt > c->out_end - dst) { - cnt = FFMAX(c->out_end - dst, 0); - c->error |= AV_LZO_OUTPUT_FULL; - } - av_memcpy_backptr(dst, back, cnt); - c->out = dst + cnt; -} - -int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen) -{ - int state = 0; - int x; - LZOContext c; - if (*outlen <= 0 || *inlen <= 0) { - int res = 0; - if (*outlen <= 0) - res |= AV_LZO_OUTPUT_FULL; - if (*inlen <= 0) - res |= AV_LZO_INPUT_DEPLETED; - return res; - } - c.in = in; - c.in_end = (const uint8_t *)in + *inlen; - c.out = c.out_start = out; - c.out_end = (uint8_t *)out + *outlen; - c.error = 0; - x = GETB(c); - if (x > 17) { - copy(&c, x - 17); - x = GETB(c); - if (x < 16) - c.error |= AV_LZO_ERROR; - } - if (c.in > c.in_end) - c.error |= AV_LZO_INPUT_DEPLETED; - while (!c.error) { - int cnt, back; - if (x > 15) { - if (x > 63) { - cnt = (x >> 5) - 1; - back = (GETB(c) << 3) + ((x >> 2) & 7) + 1; - } else if (x > 31) { - cnt = get_len(&c, x, 31); - x = GETB(c); - back = (GETB(c) << 6) + (x >> 2) + 1; - } else { - cnt = get_len(&c, x, 7); - back = (1 << 14) + ((x & 8) << 11); - x = GETB(c); - back += (GETB(c) << 6) + (x >> 2); - if (back == (1 << 14)) { - if (cnt != 1) - c.error |= AV_LZO_ERROR; - break; - } - } - } else if (!state) { - cnt = get_len(&c, x, 15); - copy(&c, cnt + 3); - x = GETB(c); - if (x > 15) - continue; - cnt = 1; - back = (1 << 11) + (GETB(c) << 2) + (x >> 2) + 1; - } else { - cnt = 0; - back = (GETB(c) << 2) + (x >> 2) + 1; - } - copy_backptr(&c, back, cnt + 2); - state = - cnt = x & 3; - copy(&c, cnt); - x = GETB(c); - } - *inlen = c.in_end - c.in; - if (c.in > c.in_end) - *inlen = 0; - *outlen = c.out_end - c.out; - return c.error; -} |