TeamHeptaMirrors/gcc
1
0
Fork 1
mirror of https://github.com/gcc-mirror/gcc.git synced 2026-05-06 14:59:39 +02:00
Code Issues Packages Projects Releases Wiki Activity

libbacktrace: support multiple zstd frames

Browse Source 
Based on patch by GitHub user ofats.

	* elf.c (elf_zstd_decompress_frame): New static function,
	broken out of elf_zstd_decompress.
	(elf_zstd_decompress): Call elf_zstd_decompress_frame in a loop.
	* zstdtest.c (test_large): Compress the file in chunks.
This commit is contained in:
Ian Lance Taylor
2026-05-03 17:58:32 -07:00
parent 6e90e4904b
commit 1e59a869af
2 changed files with 80 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

59
libbacktrace/elf.c
View File

@@ -4338,15 +4338,17 @@ elf_zstd_unpack_seq_decode (int mode,
return 1;
}
/* Decompress a zstd stream from PIN/SIN to POUT/SOUT. Code based on RFC 8878.
/* Decompress a single zstd frame from *PPIN, ending at PINEND, to *PPOUT/SOUT.
Return 1 on success, 0 on error. */
static int
elf_zstd_decompress (const unsigned char *pin, size_t sin,
unsigned char *zdebug_table, unsigned char *pout,
size_t sout)
elf_zstd_decompress_frame (const unsigned char **ppin,
const unsigned char *pinend,
unsigned char *zdebug_table, unsigned char **ppout,
size_t sout)
{
const unsigned char *pinend;
const unsigned char *pin;
unsigned char *pout;
unsigned char *poutstart;
unsigned char *poutend;
struct elf_zstd_seq_decode literal_decode;
@@ -4366,9 +4368,9 @@ elf_zstd_decompress (const unsigned char *pin, size_t sin,
uint64_t content_size;
int last_block;
pinend = pin + sin;
pin = *ppin;
pout = *ppout;
poutstart = pout;
poutend = pout + sout;
literal_decode.table = NULL;
literal_decode.table_bits = -1;
@@ -4394,7 +4396,7 @@ elf_zstd_decompress (const unsigned char *pin, size_t sin,
repeated_offset2 = 4;
repeated_offset3 = 8;
if (unlikely (sin < 4))
if (unlikely (pinend - pin < 4))
{
elf_uncompress_failed ();
return 0;
@@ -4492,12 +4494,14 @@ elf_zstd_decompress (const unsigned char *pin, size_t sin,
}
if (unlikely (content_size != (size_t) content_size
|| (size_t) content_size != sout))
|| (size_t) content_size > sout))
{
elf_uncompress_failed ();
return 0;
}
poutend = pout + content_size;
last_block = 0;
while (!last_block)
{
@@ -4996,7 +5000,42 @@ elf_zstd_decompress (const unsigned char *pin, size_t sin,
pin += 4;
}
if (pin != pinend)
*ppin = pin;
*ppout = pout;
return 1;
}
/* Decompress a zstd stream from PIN/SIN to POUT/SOUT. Code based on RFC 8878.
Return 1 on success, 0 on error. */
static int
elf_zstd_decompress (const unsigned char *pin, size_t sin,
unsigned char *zdebug_table, unsigned char *pout,
size_t sout)
{
const unsigned char *pinend;
pinend = pin + sin;
while (sin > 0)
{
const unsigned char *pin_frame;
unsigned char *pout_frame;
pin_frame = pin;
pout_frame = pout;
if (!elf_zstd_decompress_frame (&pin_frame, pinend, zdebug_table,
&pout_frame, sout))
return 0;
sin -= pin_frame - pin;
pin = pin_frame;
sout -= pout_frame - pout;
pout = pout_frame;
}
if (sout > 0)
{
elf_uncompress_failed ();
return 0;

45
libbacktrace/zstdtest.c
View File

@@ -297,8 +297,8 @@ test_large (struct backtrace_state *state ATTRIBUTE_UNUSED)
size_t orig_bufsize;
size_t i;
char *compressed_buf;
size_t compressed_bufsize;
size_t compressed_size;
size_t chunk_size;
unsigned char *uncompressed_buf;
size_t r;
clockid_t cid;
@@ -370,22 +370,39 @@ test_large (struct backtrace_state *state ATTRIBUTE_UNUSED)
return;
}
compressed_bufsize = ZSTD_compressBound (orig_bufsize);
compressed_buf = malloc (compressed_bufsize);
if (compressed_buf == NULL)
{
perror ("malloc");
goto fail;
}
/* Split the input into 100K chunks. This is to approximate the fact that lld
splits the input into 1M shards. */
r = ZSTD_compress (compressed_buf, compressed_bufsize,
orig_buf, orig_bufsize, 3);
if (ZSTD_isError (r))
compressed_size = 0;
compressed_buf = NULL;
chunk_size = 100 << 10;
for (i = 0; i < orig_bufsize; i += chunk_size)
{
fprintf (stderr, "zstd compress failed: %s\n", ZSTD_getErrorName (r));
goto fail;
size_t chunk_input_size;
size_t chunk_compressed_size;
chunk_input_size = orig_bufsize - i;
if (chunk_input_size > chunk_size)
chunk_input_size = chunk_size;
chunk_compressed_size = ZSTD_compressBound (chunk_input_size);
compressed_buf = realloc (compressed_buf, compressed_size + chunk_compressed_size);
if (compressed_buf == NULL)
{
perror ("realloc");
goto fail;
}
r = ZSTD_compress (compressed_buf + compressed_size,
chunk_compressed_size,
orig_buf + i, chunk_input_size, 3);
if (ZSTD_isError (r))
{
fprintf (stderr, "zstd compress failed: %s\n", ZSTD_getErrorName (r));
goto fail;
}
compressed_size += r;
}
compressed_size = r;
uncompressed_buf = malloc (orig_bufsize);
if (uncompressed_buf == NULL)