* LZO 1x decompression
* Copyright (c) 2006 Reimar Doeffinger
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; 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 "common.h"
-//! Avoid e.g. MPlayers fast_memcpy, it slows things down here.
-#undef memcpy
-#include <string.h>
+#include "intreadwrite.h"
#include "lzo.h"
-//! Define if we may write up to 12 bytes beyond the output buffer.
+/// 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 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;
} LZOContext;
/**
- * \brief Reads one byte from the input buffer, avoiding an overrun.
- * \return byte read
+ * @brief Reads one byte from the input buffer, avoiding an overrun.
+ * @return byte read
*/
-static inline int get_byte(LZOContext *c) {
+static inline int get_byte(LZOContext *c)
+{
if (c->in < c->in_end)
return *c->in++;
c->error |= AV_LZO_INPUT_DEPLETED;
#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
+ * @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) {
+static inline int get_len(LZOContext *c, int x, int mask)
+{
int cnt = x & mask;
if (!cnt) {
- while (!(x = get_byte(c))) cnt += 255;
+ while (!(x = get_byte(c)))
+ cnt += 255;
cnt += mask + x;
}
return cnt;
}
-//#define UNALIGNED_LOADSTORE
-#define BUILTIN_MEMCPY
-#ifdef UNALIGNED_LOADSTORE
-#define COPY2(d, s) *(uint16_t *)(d) = *(uint16_t *)(s);
-#define COPY4(d, s) *(uint32_t *)(d) = *(uint32_t *)(s);
-#elif defined(BUILTIN_MEMCPY)
-#define COPY2(d, s) memcpy(d, s, 2);
-#define COPY4(d, s) memcpy(d, s, 4);
-#else
-#define COPY2(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1];
-#define COPY4(d, s) (d)[0] = (s)[0]; (d)[1] = (s)[1]; (d)[2] = (s)[2]; (d)[3] = (s)[3];
-#endif
-
/**
- * \brief Copies bytes from input to output buffer with checking.
- * \param cnt number of bytes to copy, must be >= 0
+ * @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) {
+static inline void copy(LZOContext *c, int cnt)
+{
register const uint8_t *src = c->in;
- register uint8_t *dst = c->out;
+ register uint8_t *dst = c->out;
+ if (cnt < 0) {
+ c->error |= AV_LZO_ERROR;
+ return;
+ }
if (cnt > c->in_end - src) {
- cnt = FFMAX(c->in_end - src, 0);
+ 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);
+ cnt = FFMAX(c->out_end - dst, 0);
c->error |= AV_LZO_OUTPUT_FULL;
}
#if defined(INBUF_PADDED) && defined(OUTBUF_PADDED)
- COPY4(dst, src);
+ AV_COPY32U(dst, src);
src += 4;
dst += 4;
cnt -= 4;
if (cnt > 0)
#endif
- memcpy(dst, src, cnt);
- c->in = src + cnt;
+ memcpy(dst, src, cnt);
+ c->in = src + cnt;
c->out = dst + cnt;
}
-static inline void memcpy_backptr(uint8_t *dst, int back, int cnt);
-
/**
- * \brief Copies previously decoded bytes to current position.
- * \param back how many bytes back we start
- * \param cnt number of bytes to copy, must be >= 0
+ * @brief Copies previously decoded bytes to current position.
+ * @param back how many bytes back we start
+ * @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 const uint8_t *src = &c->out[-back];
- register uint8_t *dst = c->out;
- if (src < c->out_start || src > dst) {
+static inline void copy_backptr(LZOContext *c, int back, int cnt)
+{
+ register uint8_t *dst = c->out;
+ if (cnt <= 0) {
+ c->error |= AV_LZO_ERROR;
+ return;
+ }
+ 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);
+ cnt = FFMAX(c->out_end - dst, 0);
c->error |= AV_LZO_OUTPUT_FULL;
}
- memcpy_backptr(dst, back, cnt);
+ av_memcpy_backptr(dst, back, cnt);
c->out = dst + cnt;
}
-static inline void memcpy_backptr(uint8_t *dst, int back, int cnt) {
- const uint8_t *src = &dst[-back];
- if (back == 1) {
- memset(dst, *src, cnt);
- } else {
-#ifdef OUTBUF_PADDED
- COPY2(dst, src);
- COPY2(dst + 2, src + 2);
- src += 4;
- dst += 4;
- cnt -= 4;
- if (cnt > 0) {
- COPY2(dst, src);
- COPY2(dst + 2, src + 2);
- COPY2(dst + 4, src + 4);
- COPY2(dst + 6, src + 6);
- src += 8;
- dst += 8;
- cnt -= 8;
- }
-#endif
- if (cnt > 0) {
- int blocklen = back;
- while (cnt > blocklen) {
- memcpy(dst, src, blocklen);
- dst += blocklen;
- cnt -= blocklen;
- blocklen <<= 1;
- }
- memcpy(dst, src, cnt);
- }
- }
-}
-
-void av_memcpy_backptr(uint8_t *dst, int back, int cnt) {
- memcpy_backptr(dst, back, cnt);
-}
-
-int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen) {
- int state= 0;
+int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen)
+{
+ int state = 0;
int x;
LZOContext c;
if (!*outlen || !*inlen) {
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);
+ 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 (x < 16)
+ c.error |= AV_LZO_ERROR;
}
if (c.in > c.in_end)
c.error |= AV_LZO_INPUT_DEPLETED;
int cnt, back;
if (x > 15) {
if (x > 63) {
- cnt = (x >> 5) - 1;
+ 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);
+ 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);
+ 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)
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 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;
+ cnt = 0;
+ back = (GETB(c) << 2) + (x >> 2) + 1;
}
copy_backptr(&c, back, cnt + 2);
- state=
- cnt = x & 3;
+ state =
+ cnt = x & 3;
copy(&c, cnt);
x = GETB(c);
}
*outlen = c.out_end - c.out;
return c.error;
}
-
-#ifdef TEST
-#include <stdio.h>
-#include <lzo/lzo1x.h>
-#include "log.h"
-#define MAXSZ (10*1024*1024)
-
-/* Define one of these to 1 if you wish to benchmark liblzo
- * instead of our native implementation. */
-#define BENCHMARK_LIBLZO_SAFE 0
-#define BENCHMARK_LIBLZO_UNSAFE 0
-
-int main(int argc, char *argv[]) {
- FILE *in = fopen(argv[1], "rb");
- uint8_t *orig = av_malloc(MAXSZ + 16);
- uint8_t *comp = av_malloc(2*MAXSZ + 16);
- uint8_t *decomp = av_malloc(MAXSZ + 16);
- size_t s = fread(orig, 1, MAXSZ, in);
- lzo_uint clen = 0;
- long tmp[LZO1X_MEM_COMPRESS];
- int inlen, outlen;
- int i;
- av_log_set_level(AV_LOG_DEBUG);
- lzo1x_999_compress(orig, s, comp, &clen, tmp);
- for (i = 0; i < 300; i++) {
-START_TIMER
- inlen = clen; outlen = MAXSZ;
-#if BENCHMARK_LIBLZO_SAFE
- if (lzo1x_decompress_safe(comp, inlen, decomp, &outlen, NULL))
-#elif BENCHMARK_LIBLZO_UNSAFE
- if (lzo1x_decompress(comp, inlen, decomp, &outlen, NULL))
-#else
- if (av_lzo1x_decode(decomp, &outlen, comp, &inlen))
-#endif
- av_log(NULL, AV_LOG_ERROR, "decompression error\n");
-STOP_TIMER("lzod")
- }
- if (memcmp(orig, decomp, s))
- av_log(NULL, AV_LOG_ERROR, "decompression incorrect\n");
- else
- av_log(NULL, AV_LOG_ERROR, "decompression OK\n");
- return 0;
-}
-#endif
projects / ffmpeg / blobdiff