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Bug fixes for the brotli encoder and decoder.

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This commit is contained in:
Zoltan Szabadka
2014-01-06 16:01:57 +01:00
parent b89f3be40b
commit 40955ce409
4 changed files with 85 additions and 58 deletions
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brotli/dec/decode.c
+65 -25
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@@ -199,6 +199,9 @@ static int ReadHuffmanCodeLengths(
repeat <<= extra_bits;
}
repeat += BrotliReadBits(br, extra_bits) + 3;
if (repeat + symbol > num_symbols) {
goto End;
}
if (code_len == kCodeLengthRepeatCode) {
repeat_length = prev_code_len;
for (; i < repeat; ++i) {
@@ -258,7 +261,7 @@ static int ReadHuffmanCode(int alphabet_size,
}
memset(code_lengths, 0, alphabet_size);
for (i = 0; i < num_symbols; ++i) {
symbols[i] = BrotliReadBits(br, max_bits);
symbols[i] = BrotliReadBits(br, max_bits) % alphabet_size;
code_lengths[symbols[i]] = 2;
}
code_lengths[symbols[0]] = 1;
@@ -386,8 +389,8 @@ static void ReadInsertAndCopy(const HuffmanTree* tree,
}
}
static int TranslateShortCodes(int code, int* ringbuffer, size_t index) {
int val;
static size_t TranslateShortCodes(int code, int* ringbuffer, size_t index) {
size_t val;
if (code < NUM_DISTANCE_SHORT_CODES) {
index += kDistanceShortCodeIndexOffset[code];
index &= 3;
@@ -427,9 +430,13 @@ typedef struct {
static void HuffmanTreeGroupInit(HuffmanTreeGroup* group, int alphabet_size,
int ntrees) {
int i;
group->alphabet_size = alphabet_size;
group->num_htrees = ntrees;
group->htrees = (HuffmanTree*)malloc(sizeof(HuffmanTree) * ntrees);
for (i = 0; i < ntrees; ++i) {
group->htrees[i].root_ = NULL;
}
}
static void HuffmanTreeGroupRelease(HuffmanTreeGroup* group) {
@@ -437,7 +444,9 @@ static void HuffmanTreeGroupRelease(HuffmanTreeGroup* group) {
for (i = 0; i < group->num_htrees; ++i) {
BrotliHuffmanTreeRelease(&group->htrees[i]);
}
free(group->htrees);
if (group->htrees) {
free(group->htrees);
}
}
static int HuffmanTreeGroupDecode(HuffmanTreeGroup* group,
@@ -466,6 +475,9 @@ static int DecodeContextMap(int context_map_size,
BROTLI_LOG_UINT(*num_htrees);
*context_map = (uint8_t*)malloc(context_map_size);
if (*context_map == 0) {
return 0;
}
if (*num_htrees <= 1) {
memset(*context_map, 0, context_map_size);
return 1;
@@ -497,6 +509,10 @@ static int DecodeContextMap(int context_map_size,
} else if (code <= max_run_length_prefix) {
int reps = 1 + (1 << code) + BrotliReadBits(br, code);
while (--reps) {
if (i >= context_map_size) {
ok = 0;
goto End;
}
(*context_map)[i] = 0;
++i;
}
@@ -514,12 +530,13 @@ static int DecodeContextMap(int context_map_size,
return ok;
}
static BROTLI_INLINE void DecodeBlockType(const HuffmanTree* trees,
int tree_type,
int* block_types,
int* ringbuffers,
size_t* indexes,
BrotliBitReader* br) {
static BROTLI_INLINE void DecodeBlockType(const int max_block_type,
const HuffmanTree* trees,
int tree_type,
int* block_types,
int* ringbuffers,
size_t* indexes,
BrotliBitReader* br) {
int* ringbuffer = ringbuffers + tree_type * 2;
size_t* index = indexes + tree_type;
int type_code = ReadSymbol(trees + tree_type, br);
@@ -531,6 +548,9 @@ static BROTLI_INLINE void DecodeBlockType(const HuffmanTree* trees,
} else {
block_type = type_code - 2;
}
if (block_type >= max_block_type) {
block_type -= max_block_type;
}
block_types[tree_type] = block_type;
ringbuffer[(*index) & 1] = block_type;
++(*index);
@@ -639,7 +659,9 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
HuffmanTreeGroup hgroup[3];
BrotliBitReader br;
static const int kRingBufferWriteAheadSlack = 16;
/* 16 bytes would be enough, but we add some more slack for transforms */
/* to work at the end of the ringbuffer. */
static const int kRingBufferWriteAheadSlack = 128;
static const int kMaxDictionaryWordLength = 0;
@@ -656,6 +678,9 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
ringbuffer = (uint8_t*)malloc(ringbuffer_size +
kRingBufferWriteAheadSlack +
kMaxDictionaryWordLength);
if (!ringbuffer) {
ok = 0;
}
ringbuffer_end = ringbuffer + ringbuffer_size;
while (!input_end && ok) {
@@ -755,6 +780,10 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
num_distance_codes = (num_direct_distance_codes +
(48 << distance_postfix_bits));
context_modes = (uint8_t*)malloc(num_block_types[0]);
if (context_modes == 0) {
ok = 0;
goto End;
}
for (i = 0; i < num_block_types[0]; ++i) {
context_modes[i] = BrotliReadBits(&br, 2) << 1;
BROTLI_LOG_ARRAY_INDEX(context_modes, i);
@@ -792,7 +821,7 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
int insert_length;
int copy_length;
int distance_code;
int distance;
size_t distance;
size_t max_distance;
uint8_t context;
int j;
@@ -804,7 +833,8 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
goto End;
}
if (block_length[1] == 0) {
DecodeBlockType(block_type_trees, 1, block_type, block_type_rb,
DecodeBlockType(num_block_types[1],
block_type_trees, 1, block_type, block_type_rb,
block_type_rb_index, &br);
block_length[1] = ReadBlockLength(&block_len_trees[1], &br);
}
@@ -821,7 +851,8 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
goto End;
}
if (block_length[0] == 0) {
DecodeBlockType(block_type_trees, 0, block_type, block_type_rb,
DecodeBlockType(num_block_types[0],
block_type_trees, 0, block_type, block_type_rb,
block_type_rb_index, &br);
block_length[0] = ReadBlockLength(&block_len_trees[0], &br);
context_offset = block_type[0] << kLiteralContextBits;
@@ -858,7 +889,8 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
goto End;
}
if (block_length[2] == 0) {
DecodeBlockType(block_type_trees, 2, block_type, block_type_rb,
DecodeBlockType(num_block_types[2],
block_type_trees, 2, block_type, block_type_rb,
block_type_rb_index, &br);
block_length[2] = ReadBlockLength(&block_len_trees[2], &br);
dist_htree_index = block_type[2];
@@ -891,16 +923,16 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
copy_dst = &ringbuffer[pos & ringbuffer_mask];
if ((size_t)distance > max_distance) {
if (distance > max_distance) {
printf("Invalid backward reference. pos: %lu distance: %d "
"len: %d end: %lu\n", (unsigned long)pos, distance, copy_length,
(unsigned long)meta_block_end_pos);
"len: %d end: %lu\n", (unsigned long)pos, (int)distance,
copy_length, (unsigned long)meta_block_end_pos);
ok = 0;
goto End;
} else {
if (pos + copy_length > meta_block_end_pos) {
printf("Invalid backward reference. pos: %lu distance: %d "
"len: %d end: %lu\n", (unsigned long)pos, distance,
"len: %d end: %lu\n", (unsigned long)pos, (int)distance,
copy_length, (unsigned long)meta_block_end_pos);
ok = 0;
goto End;
@@ -942,9 +974,15 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
prev_byte2 = ringbuffer[(pos - 2) & ringbuffer_mask];
}
End:
free(context_modes);
free(context_map);
free(dist_context_map);
if (context_modes != 0) {
free(context_modes);
}
if (context_map != 0) {
free(context_map);
}
if (dist_context_map != 0) {
free(dist_context_map);
}
for (i = 0; i < 3; ++i) {
HuffmanTreeGroupRelease(&hgroup[i]);
BrotliHuffmanTreeRelease(&block_type_trees[i]);
@@ -952,10 +990,12 @@ int BrotliDecompress(BrotliInput input, BrotliOutput output) {
}
}
if (BrotliWrite(output, ringbuffer, pos & ringbuffer_mask) < 0) {
ok = 0;
if (ringbuffer != 0) {
if (BrotliWrite(output, ringbuffer, pos & ringbuffer_mask) < 0) {
ok = 0;
}
free(ringbuffer);
}
free(ringbuffer);
return ok;
}