177 lines
5.6 KiB
Diff
177 lines
5.6 KiB
Diff
Based on 5e592c66bdf76dfc8445b332f7a5088ca504ee90 Mon Sep 17 00:00:00 2001
|
|
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
|
|
Date: Fri, 4 Jul 2014 19:53:58 -0400
|
|
Subject: [PATCH] journal/compress: return early in uncompress_startswith
|
|
|
|
uncompress_startswith would always decode the whole stream, even
|
|
if it did not start with the given prefix.
|
|
|
|
Reallocation policy was also strange.
|
|
---
|
|
src/journal/compress.c | 91 ++++++++++++++-----------------------------------
|
|
1 file changed, 27 insertions(+), 64 deletions(-)
|
|
|
|
--- src/journal/compress.c
|
|
+++ src/journal/compress.c 2014-07-09 00:00:00.000000000 +0000
|
|
@@ -69,10 +69,9 @@ fail:
|
|
bool uncompress_blob(const void *src, uint64_t src_size,
|
|
void **dst, uint64_t *dst_alloc_size, uint64_t* dst_size, uint64_t dst_max) {
|
|
|
|
- lzma_stream s = LZMA_STREAM_INIT;
|
|
+ _cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
|
|
lzma_ret ret;
|
|
uint64_t space;
|
|
- bool b = false;
|
|
|
|
assert(src);
|
|
assert(src_size > 0);
|
|
@@ -85,26 +84,18 @@ bool uncompress_blob(const void *src, ui
|
|
if (ret != LZMA_OK)
|
|
return false;
|
|
|
|
- if (*dst_alloc_size <= src_size) {
|
|
- void *p;
|
|
-
|
|
- p = realloc(*dst, src_size*2);
|
|
- if (!p)
|
|
- return false;
|
|
-
|
|
- *dst = p;
|
|
- *dst_alloc_size = src_size*2;
|
|
- }
|
|
+ space = MIN(src_size * 2, dst_max ?: (uint64_t) -1);
|
|
+ if (!greedy_realloc(dst, dst_alloc_size, space, 1))
|
|
+ return false;
|
|
|
|
s.next_in = src;
|
|
s.avail_in = src_size;
|
|
|
|
s.next_out = *dst;
|
|
- space = dst_max > 0 ? MIN(*dst_alloc_size, dst_max) : *dst_alloc_size;
|
|
s.avail_out = space;
|
|
|
|
for (;;) {
|
|
- void *p;
|
|
+ uint64_t used;
|
|
|
|
ret = lzma_code(&s, LZMA_FINISH);
|
|
|
|
@@ -112,31 +103,25 @@ bool uncompress_blob(const void *src, ui
|
|
break;
|
|
|
|
if (ret != LZMA_OK)
|
|
- goto fail;
|
|
+ return false;
|
|
|
|
if (dst_max > 0 && (space - s.avail_out) >= dst_max)
|
|
break;
|
|
|
|
- p = realloc(*dst, space*2);
|
|
- if (!p)
|
|
- goto fail;
|
|
-
|
|
- s.next_out = (uint8_t*) p + ((uint8_t*) s.next_out - (uint8_t*) *dst);
|
|
- s.avail_out += space;
|
|
+ if (dst_max > 0 && space == dst_max)
|
|
+ return false;
|
|
|
|
- space *= 2;
|
|
+ used = space - s.avail_out;
|
|
+ space = MIN(2 * space, dst_max ?: (uint64_t) -1);
|
|
+ if (!greedy_realloc(dst, dst_alloc_size, space, 1))
|
|
+ return false;
|
|
|
|
- *dst = p;
|
|
- *dst_alloc_size = space;
|
|
+ s.avail_out = space - used;
|
|
+ s.next_out = *dst + used;
|
|
}
|
|
|
|
*dst_size = space - s.avail_out;
|
|
- b = true;
|
|
-
|
|
-fail:
|
|
- lzma_end(&s);
|
|
-
|
|
- return b;
|
|
+ return true;
|
|
}
|
|
|
|
bool uncompress_startswith(const void *src, uint64_t src_size,
|
|
@@ -144,9 +129,8 @@ bool uncompress_startswith(const void *s
|
|
const void *prefix, uint64_t prefix_len,
|
|
uint8_t extra) {
|
|
|
|
- lzma_stream s = LZMA_STREAM_INIT;
|
|
+ _cleanup_(lzma_end) lzma_stream s = LZMA_STREAM_INIT;
|
|
lzma_ret ret;
|
|
- bool b = false;
|
|
|
|
/* Checks whether the uncompressed blob starts with the
|
|
* mentioned prefix. The byte extra needs to follow the
|
|
@@ -163,16 +147,8 @@ bool uncompress_startswith(const void *s
|
|
if (ret != LZMA_OK)
|
|
return false;
|
|
|
|
- if (*buffer_size <= prefix_len) {
|
|
- void *p;
|
|
-
|
|
- p = realloc(*buffer, prefix_len*2);
|
|
- if (!p)
|
|
- return false;
|
|
-
|
|
- *buffer = p;
|
|
- *buffer_size = prefix_len*2;
|
|
- }
|
|
+ if (!(greedy_realloc(buffer, buffer_size, prefix_len + 1, 1)))
|
|
+ return false;
|
|
|
|
s.next_in = src;
|
|
s.avail_in = src_size;
|
|
@@ -181,36 +157,23 @@ bool uncompress_startswith(const void *s
|
|
s.avail_out = *buffer_size;
|
|
|
|
for (;;) {
|
|
- void *p;
|
|
-
|
|
ret = lzma_code(&s, LZMA_FINISH);
|
|
|
|
if (ret != LZMA_STREAM_END && ret != LZMA_OK)
|
|
- goto fail;
|
|
+ return false;
|
|
|
|
- if ((*buffer_size - s.avail_out > prefix_len) &&
|
|
- memcmp(*buffer, prefix, prefix_len) == 0 &&
|
|
- ((const uint8_t*) *buffer)[prefix_len] == extra)
|
|
- break;
|
|
+ if (*buffer_size - s.avail_out >= prefix_len + 1)
|
|
+ return memcmp(*buffer, prefix, prefix_len) == 0 &&
|
|
+ ((const uint8_t*) *buffer)[prefix_len] == extra;
|
|
|
|
if (ret == LZMA_STREAM_END)
|
|
- goto fail;
|
|
-
|
|
- p = realloc(*buffer, *buffer_size*2);
|
|
- if (!p)
|
|
- goto fail;
|
|
+ return false;
|
|
|
|
- s.next_out = (uint8_t*) p + ((uint8_t*) s.next_out - (uint8_t*) *buffer);
|
|
s.avail_out += *buffer_size;
|
|
|
|
- *buffer = p;
|
|
- *buffer_size *= 2;
|
|
- }
|
|
-
|
|
- b = true;
|
|
-
|
|
-fail:
|
|
- lzma_end(&s);
|
|
+ if (!(greedy_realloc(buffer, buffer_size, *buffer_size * 2, 1)))
|
|
+ return false;
|
|
|
|
- return b;
|
|
+ s.next_out = *buffer + *buffer_size - s.avail_out;
|
|
+ }
|
|
}
|