liblzma: Use lzma_memcmplen() in the match finders.
This doesn't change the match finder output.
diff --git a/src/liblzma/lz/lz_encoder.c b/src/liblzma/lz/lz_encoder.c
index 76954e4..2033844 100644
--- a/src/liblzma/lz/lz_encoder.c
+++ b/src/liblzma/lz/lz_encoder.c
@@ -20,6 +20,8 @@
# include "lz_encoder_hash_table.h"
#endif
+#include "memcmplen.h"
+
struct lzma_coder_s {
/// LZ-based encoder e.g. LZMA
@@ -363,9 +365,18 @@
{
// Allocate the history buffer.
if (mf->buffer == NULL) {
- mf->buffer = lzma_alloc(mf->size, allocator);
+ // lzma_memcmplen() is used for the dictionary buffer
+ // so we need to allocate a few extra bytes to prevent
+ // it from reading past the end of the buffer.
+ mf->buffer = lzma_alloc(mf->size + LZMA_MEMCMPLEN_EXTRA,
+ allocator);
if (mf->buffer == NULL)
return true;
+
+ // Keep Valgrind happy with lzma_memcmplen() and initialize
+ // the extra bytes whose value may get read but which will
+ // effectively get ignored.
+ memzero(mf->buffer + mf->size, LZMA_MEMCMPLEN_EXTRA);
}
// Use cyclic_size as initial mf->offset. This allows
diff --git a/src/liblzma/lz/lz_encoder_mf.c b/src/liblzma/lz/lz_encoder_mf.c
index bf787f4..6dc39f4 100644
--- a/src/liblzma/lz/lz_encoder_mf.c
+++ b/src/liblzma/lz/lz_encoder_mf.c
@@ -13,6 +13,7 @@
#include "lz_encoder.h"
#include "lz_encoder_hash.h"
+#include "memcmplen.h"
/// \brief Find matches starting from the current byte
@@ -65,9 +66,7 @@
// here because the match distances are zero based.
const uint8_t *p2 = p1 - matches[count - 1].dist - 1;
- while (len_best < limit
- && p1[len_best] == p2[len_best])
- ++len_best;
+ len_best = lzma_memcmplen(p1, p2, len_best, limit);
}
}
@@ -272,10 +271,7 @@
+ (delta > cyclic_pos ? cyclic_size : 0)];
if (pb[len_best] == cur[len_best] && pb[0] == cur[0]) {
- uint32_t len = 0;
- while (++len != len_limit)
- if (pb[len] != cur[len])
- break;
+ uint32_t len = lzma_memcmplen(pb, cur, 1, len_limit);
if (len_best < len) {
len_best = len;
@@ -321,9 +317,8 @@
uint32_t len_best = 2;
if (delta2 < mf->cyclic_size && *(cur - delta2) == *cur) {
- for ( ; len_best != len_limit; ++len_best)
- if (*(cur + len_best - delta2) != cur[len_best])
- break;
+ len_best = lzma_memcmplen(cur - delta2, cur,
+ len_best, len_limit);
matches[0].len = len_best;
matches[0].dist = delta2 - 1;
@@ -400,9 +395,8 @@
}
if (matches_count != 0) {
- for ( ; len_best != len_limit; ++len_best)
- if (*(cur + len_best - delta2) != cur[len_best])
- break;
+ len_best = lzma_memcmplen(cur - delta2, cur,
+ len_best, len_limit);
matches[matches_count - 1].len = len_best;
@@ -487,9 +481,7 @@
uint32_t len = my_min(len0, len1);
if (pb[len] == cur[len]) {
- while (++len != len_limit)
- if (pb[len] != cur[len])
- break;
+ len = lzma_memcmplen(pb, cur, len + 1, len_limit);
if (len_best < len) {
len_best = len;
@@ -552,9 +544,7 @@
uint32_t len = my_min(len0, len1);
if (pb[len] == cur[len]) {
- while (++len != len_limit)
- if (pb[len] != cur[len])
- break;
+ len = lzma_memcmplen(pb, cur, len + 1, len_limit);
if (len == len_limit) {
*ptr1 = pair[0];
@@ -715,9 +705,8 @@
}
if (matches_count != 0) {
- for ( ; len_best != len_limit; ++len_best)
- if (*(cur + len_best - delta2) != cur[len_best])
- break;
+ len_best = lzma_memcmplen(
+ cur, cur - delta2, len_best, len_limit);
matches[matches_count - 1].len = len_best;
