* 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 "avutil.h"
#include "common.h"
-//! avoid e.g. MPlayers fast_memcpy, it slows things down here
+//! Avoid e.g. MPlayers fast_memcpy, it slows things down here.
#undef memcpy
#include <string.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;
} LZOContext;
/**
- * \brief read one byte from input buffer, avoiding overrun
+ * \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 |= LZO_INPUT_DEPLETED;
+ c->error |= AV_LZO_INPUT_DEPLETED;
return 1;
}
#endif
/**
- * \brief decode a length value in the coding used by lzo
+ * \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
#endif
/**
- * \brief copy bytes from input to output buffer with checking
+ * \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 uint8_t *dst = c->out;
if (cnt > c->in_end - src) {
cnt = FFMAX(c->in_end - src, 0);
- c->error |= LZO_INPUT_DEPLETED;
+ c->error |= AV_LZO_INPUT_DEPLETED;
}
if (cnt > c->out_end - dst) {
cnt = FFMAX(c->out_end - dst, 0);
- c->error |= LZO_OUTPUT_FULL;
+ c->error |= AV_LZO_OUTPUT_FULL;
}
#if defined(INBUF_PADDED) && defined(OUTBUF_PADDED)
COPY4(dst, src);
static inline void memcpy_backptr(uint8_t *dst, int back, int cnt);
/**
- * \brief copy previously decoded bytes to current position
+ * \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
*
register const uint8_t *src = &c->out[-back];
register uint8_t *dst = c->out;
if (src < c->out_start || src > dst) {
- c->error |= LZO_INVALID_BACKPTR;
+ c->error |= AV_LZO_INVALID_BACKPTR;
return;
}
if (cnt > c->out_end - dst) {
cnt = FFMAX(c->out_end - dst, 0);
- c->error |= LZO_OUTPUT_FULL;
+ c->error |= AV_LZO_OUTPUT_FULL;
}
memcpy_backptr(dst, back, cnt);
c->out = dst + cnt;
}
}
-/**
- * \brief deliberately overlapping memcpy implementation
- * \param dst destination buffer; must be padded with 12 additional bytes
- * \param back how many bytes back we start (the initial size of the overlapping window)
- * \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.
- */
void av_memcpy_backptr(uint8_t *dst, int back, int cnt) {
memcpy_backptr(dst, back, cnt);
}
-/**
- * \brief decode LZO 1x compressed data
- * \param out output buffer
- * \param outlen size of output buffer, number of bytes left are returned here
- * \param in input buffer
- * \param inlen size of input buffer, number of bytes left are returned here
- * \return 0 on success, otherwise error flags, see lzo.h
- *
- * make sure all buffers are appropriately padded, in must provide
- * LZO_INPUT_PADDING, out must provide LZO_OUTPUT_PADDING additional bytes
- */
-int lzo1x_decode(void *out, int *outlen, const void *in, int *inlen) {
+int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen) {
int state= 0;
int x;
LZOContext c;
+ if (!*outlen || !*inlen) {
+ int res = 0;
+ if (!*outlen)
+ res |= AV_LZO_OUTPUT_FULL;
+ if (!*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;
if (x > 17) {
copy(&c, x - 17);
x = GETB(c);
- if (x < 16) c.error |= LZO_ERROR;
+ if (x < 16) c.error |= AV_LZO_ERROR;
}
if (c.in > c.in_end)
- c.error |= LZO_INPUT_DEPLETED;
+ c.error |= AV_LZO_INPUT_DEPLETED;
while (!c.error) {
int cnt, back;
if (x > 15) {
back += (GETB(c) << 6) + (x >> 2);
if (back == (1 << 14)) {
if (cnt != 1)
- c.error |= LZO_ERROR;
+ c.error |= AV_LZO_ERROR;
break;
}
}
#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);
long tmp[LZO1X_MEM_COMPRESS];
int inlen, outlen;
int i;
- av_log_level = AV_LOG_DEBUG;
+ 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;
-#ifdef LIBLZO
+#if BENCHMARK_LIBLZO_SAFE
if (lzo1x_decompress_safe(comp, inlen, decomp, &outlen, NULL))
-#elif defined(LIBLZO_UNSAFE)
+#elif BENCHMARK_LIBLZO_UNSAFE
if (lzo1x_decompress(comp, inlen, decomp, &outlen, NULL))
#else
- if (lzo1x_decode(decomp, &outlen, comp, &inlen))
+ 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");
+ av_log(NULL, AV_LOG_ERROR, "decompression OK\n");
return 0;
}
#endif