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-rw-r--r--contrib/xz/src/liblzma/lz/lz_encoder.c124
1 files changed, 73 insertions, 51 deletions
diff --git a/contrib/xz/src/liblzma/lz/lz_encoder.c b/contrib/xz/src/liblzma/lz/lz_encoder.c
index e240696..48bc487 100644
--- a/contrib/xz/src/liblzma/lz/lz_encoder.c
+++ b/contrib/xz/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
@@ -76,8 +78,9 @@ move_window(lzma_mf *mf)
/// This function must not be called once it has returned LZMA_STREAM_END.
///
static lzma_ret
-fill_window(lzma_coder *coder, lzma_allocator *allocator, const uint8_t *in,
- size_t *in_pos, size_t in_size, lzma_action action)
+fill_window(lzma_coder *coder, const lzma_allocator *allocator,
+ const uint8_t *in, size_t *in_pos, size_t in_size,
+ lzma_action action)
{
assert(coder->mf.read_pos <= coder->mf.write_pos);
@@ -107,6 +110,12 @@ fill_window(lzma_coder *coder, lzma_allocator *allocator, const uint8_t *in,
coder->mf.write_pos = write_pos;
+ // Silence Valgrind. lzma_memcmplen() can read extra bytes
+ // and Valgrind will give warnings if those bytes are uninitialized
+ // because Valgrind cannot see that the values of the uninitialized
+ // bytes are eventually ignored.
+ memzero(coder->mf.buffer + write_pos, LZMA_MEMCMPLEN_EXTRA);
+
// If end of stream has been reached or flushing completed, we allow
// the encoder to process all the input (that is, read_pos is allowed
// to reach write_pos). Otherwise we keep keep_size_after bytes
@@ -130,7 +139,7 @@ fill_window(lzma_coder *coder, lzma_allocator *allocator, const uint8_t *in,
&& coder->mf.read_pos < coder->mf.read_limit) {
// Match finder may update coder->pending and expects it to
// start from zero, so use a temporary variable.
- const size_t pending = coder->mf.pending;
+ const uint32_t pending = coder->mf.pending;
coder->mf.pending = 0;
// Rewind read_pos so that the match finder can hash
@@ -148,7 +157,7 @@ fill_window(lzma_coder *coder, lzma_allocator *allocator, const uint8_t *in,
static lzma_ret
-lz_encode(lzma_coder *coder, lzma_allocator *allocator,
+lz_encode(lzma_coder *coder, const lzma_allocator *allocator,
const uint8_t *restrict in, size_t *restrict in_pos,
size_t in_size,
uint8_t *restrict out, size_t *restrict out_pos,
@@ -179,7 +188,7 @@ lz_encode(lzma_coder *coder, lzma_allocator *allocator,
static bool
-lz_encoder_prepare(lzma_mf *mf, lzma_allocator *allocator,
+lz_encoder_prepare(lzma_mf *mf, const lzma_allocator *allocator,
const lzma_lz_options *lz_options)
{
// For now, the dictionary size is limited to 1.5 GiB. This may grow
@@ -325,25 +334,22 @@ lz_encoder_prepare(lzma_mf *mf, lzma_allocator *allocator,
hs += HASH_4_SIZE;
*/
- // If the above code calculating hs is modified, make sure that
- // this assertion stays valid (UINT32_MAX / 5 is not strictly the
- // exact limit). If it doesn't, you need to calculate that
- // hash_size_sum + sons_count cannot overflow.
- assert(hs < UINT32_MAX / 5);
-
- const uint32_t old_count = mf->hash_size_sum + mf->sons_count;
- mf->hash_size_sum = hs;
+ const uint32_t old_hash_count = mf->hash_count;
+ const uint32_t old_sons_count = mf->sons_count;
+ mf->hash_count = hs;
mf->sons_count = mf->cyclic_size;
if (is_bt)
mf->sons_count *= 2;
- const uint32_t new_count = mf->hash_size_sum + mf->sons_count;
-
// Deallocate the old hash array if it exists and has different size
// than what is needed now.
- if (old_count != new_count) {
+ if (old_hash_count != mf->hash_count
+ || old_sons_count != mf->sons_count) {
lzma_free(mf->hash, allocator);
mf->hash = NULL;
+
+ lzma_free(mf->son, allocator);
+ mf->son = NULL;
}
// Maximum number of match finder cycles
@@ -360,14 +366,23 @@ lz_encoder_prepare(lzma_mf *mf, lzma_allocator *allocator,
static bool
-lz_encoder_init(lzma_mf *mf, lzma_allocator *allocator,
+lz_encoder_init(lzma_mf *mf, const lzma_allocator *allocator,
const lzma_lz_options *lz_options)
{
// 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
@@ -381,43 +396,48 @@ lz_encoder_init(lzma_mf *mf, lzma_allocator *allocator,
mf->write_pos = 0;
mf->pending = 0;
- // Allocate match finder's hash array.
- const size_t alloc_count = mf->hash_size_sum + mf->sons_count;
-
#if UINT32_MAX >= SIZE_MAX / 4
// Check for integer overflow. (Huge dictionaries are not
// possible on 32-bit CPU.)
- if (alloc_count > SIZE_MAX / sizeof(uint32_t))
+ if (mf->hash_count > SIZE_MAX / sizeof(uint32_t)
+ || mf->sons_count > SIZE_MAX / sizeof(uint32_t))
return true;
#endif
+ // Allocate and initialize the hash table. Since EMPTY_HASH_VALUE
+ // is zero, we can use lzma_alloc_zero() or memzero() for mf->hash.
+ //
+ // We don't need to initialize mf->son, but not doing that may
+ // make Valgrind complain in normalization (see normalize() in
+ // lz_encoder_mf.c). Skipping the initialization is *very* good
+ // when big dictionary is used but only small amount of data gets
+ // actually compressed: most of the mf->son won't get actually
+ // allocated by the kernel, so we avoid wasting RAM and improve
+ // initialization speed a lot.
if (mf->hash == NULL) {
- mf->hash = lzma_alloc(alloc_count * sizeof(uint32_t),
+ mf->hash = lzma_alloc_zero(mf->hash_count * sizeof(uint32_t),
+ allocator);
+ mf->son = lzma_alloc(mf->sons_count * sizeof(uint32_t),
allocator);
- if (mf->hash == NULL)
- return true;
- }
- mf->son = mf->hash + mf->hash_size_sum;
- mf->cyclic_pos = 0;
+ if (mf->hash == NULL || mf->son == NULL) {
+ lzma_free(mf->hash, allocator);
+ mf->hash = NULL;
- // Initialize the hash table. Since EMPTY_HASH_VALUE is zero, we
- // can use memset().
+ lzma_free(mf->son, allocator);
+ mf->son = NULL;
+
+ return true;
+ }
+ } else {
/*
- for (uint32_t i = 0; i < hash_size_sum; ++i)
- mf->hash[i] = EMPTY_HASH_VALUE;
+ for (uint32_t i = 0; i < mf->hash_count; ++i)
+ mf->hash[i] = EMPTY_HASH_VALUE;
*/
- memzero(mf->hash, (size_t)(mf->hash_size_sum) * sizeof(uint32_t));
+ memzero(mf->hash, mf->hash_count * sizeof(uint32_t));
+ }
- // We don't need to initialize mf->son, but not doing that will
- // make Valgrind complain in normalization (see normalize() in
- // lz_encoder_mf.c).
- //
- // Skipping this initialization is *very* good when big dictionary is
- // used but only small amount of data gets actually compressed: most
- // of the mf->hash won't get actually allocated by the kernel, so
- // we avoid wasting RAM and improve initialization speed a lot.
- //memzero(mf->son, (size_t)(mf->sons_count) * sizeof(uint32_t));
+ mf->cyclic_pos = 0;
// Handle preset dictionary.
if (lz_options->preset_dict != NULL
@@ -445,7 +465,8 @@ lzma_lz_encoder_memusage(const lzma_lz_options *lz_options)
lzma_mf mf = {
.buffer = NULL,
.hash = NULL,
- .hash_size_sum = 0,
+ .son = NULL,
+ .hash_count = 0,
.sons_count = 0,
};
@@ -454,17 +475,17 @@ lzma_lz_encoder_memusage(const lzma_lz_options *lz_options)
return UINT64_MAX;
// Calculate the memory usage.
- return (uint64_t)(mf.hash_size_sum + mf.sons_count)
- * sizeof(uint32_t)
- + (uint64_t)(mf.size) + sizeof(lzma_coder);
+ return ((uint64_t)(mf.hash_count) + mf.sons_count) * sizeof(uint32_t)
+ + mf.size + sizeof(lzma_coder);
}
static void
-lz_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
+lz_encoder_end(lzma_coder *coder, const lzma_allocator *allocator)
{
lzma_next_end(&coder->next, allocator);
+ lzma_free(coder->mf.son, allocator);
lzma_free(coder->mf.hash, allocator);
lzma_free(coder->mf.buffer, allocator);
@@ -479,7 +500,7 @@ lz_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
static lzma_ret
-lz_encoder_update(lzma_coder *coder, lzma_allocator *allocator,
+lz_encoder_update(lzma_coder *coder, const lzma_allocator *allocator,
const lzma_filter *filters_null lzma_attribute((__unused__)),
const lzma_filter *reversed_filters)
{
@@ -495,10 +516,10 @@ lz_encoder_update(lzma_coder *coder, lzma_allocator *allocator,
extern lzma_ret
-lzma_lz_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
+lzma_lz_encoder_init(lzma_next_coder *next, const lzma_allocator *allocator,
const lzma_filter_info *filters,
lzma_ret (*lz_init)(lzma_lz_encoder *lz,
- lzma_allocator *allocator, const void *options,
+ const lzma_allocator *allocator, const void *options,
lzma_lz_options *lz_options))
{
#ifdef HAVE_SMALL
@@ -522,7 +543,8 @@ lzma_lz_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
next->coder->mf.buffer = NULL;
next->coder->mf.hash = NULL;
- next->coder->mf.hash_size_sum = 0;
+ next->coder->mf.son = NULL;
+ next->coder->mf.hash_count = 0;
next->coder->mf.sons_count = 0;
next->coder->next = LZMA_NEXT_CODER_INIT;
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