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authorMichael Niedermayer <michaelni@gmx.at>2012-10-25 13:15:58 +0200
committerMichael Niedermayer <michaelni@gmx.at>2012-10-25 13:15:58 +0200
commitaa604e8e33ae06f3a106e44fff798fdd70d77230 (patch)
treede1f5670244e74d90e97b8dc69f054768c363959 /libavutil/mem.c
parentd312ffdd79bd22b5a051790c993eda6b1366cdfc (diff)
parent2a91ada8282f18d2807abee5188225bba1b19bda (diff)
Merge remote-tracking branch 'qatar/master'
* qatar/master: avutil: Make LZO decoder code configure-time selectable avutil: Move memcpy_backptr() to mem.c configure: detect parisc64 automatically configure: detect ppc64 automatically configure: detect mips64 automatically configure: generalise 64-bit test smoothstreamingenc: Don't assume streams start from timestamp 0 Conflicts: configure libavutil/Makefile libavutil/lzo.c libavutil/lzo.h libavutil/mem.c libavutil/mem.h Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavutil/mem.c')
-rw-r--r--libavutil/mem.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/libavutil/mem.c b/libavutil/mem.c
index 0c1c4b25a0..f3853b0827 100644
--- a/libavutil/mem.c
+++ b/libavutil/mem.c
@@ -29,6 +29,7 @@
#include "config.h"
#include <limits.h>
+#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#if HAVE_MALLOC_H
@@ -36,6 +37,7 @@
#endif
#include "avutil.h"
+#include "intreadwrite.h"
#include "mem.h"
/* here we can use OS-dependent allocation functions */
@@ -244,3 +246,38 @@ void av_dynarray_add(void *tab_ptr, int *nb_ptr, void *elem)
*nb_ptr = nb;
}
+void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
+{
+ const uint8_t *src = &dst[-back];
+ if (back <= 1) {
+ memset(dst, *src, cnt);
+ } else {
+ if (cnt >= 4) {
+ AV_COPY16U(dst, src);
+ AV_COPY16U(dst + 2, src + 2);
+ src += 4;
+ dst += 4;
+ cnt -= 4;
+ }
+ if (cnt >= 8) {
+ AV_COPY16U(dst, src);
+ AV_COPY16U(dst + 2, src + 2);
+ AV_COPY16U(dst + 4, src + 4);
+ AV_COPY16U(dst + 6, src + 6);
+ src += 8;
+ dst += 8;
+ cnt -= 8;
+ }
+ if (cnt > 0) {
+ int blocklen = back;
+ while (cnt > blocklen) {
+ memcpy(dst, src, blocklen);
+ dst += blocklen;
+ cnt -= blocklen;
+ blocklen <<= 1;
+ }
+ memcpy(dst, src, cnt);
+ }
+ }
+}
+