mirror of
https://github.com/wolfcw/libfaketime.git
synced 2026-05-17 00:26:16 +03:00
712733e5f0
Compiling tests with GCC 16 results into this warning:
gcc -shared -o libmallocintercept.so -fpic -std=gnu99 -Wall -DFAKE_STAT -Werror -Wextra -U_FILE_OFFSET_BITS -U_TIME_BITS libmallocintercept.c
libmallocintercept.c: In function ‘free’:
libmallocintercept.c:79:12: error: variable ‘ptr2’ set but not used [-Werror=unused-but-set-variable=]
79 | long int ptr2 = (long int) ptr; ptr2 -= (long int) ptr;
| ^~~~
cc1: all warnings being treated as errors
The ptr2 variable was added in the past to silence compiler warnings,
probably for the very same reason (commits
75cbe8e507 and
2bfbe19f71). GCC 16 is smarter and
discovers that the ptr2 variables is not needed.
This patch changes the work around to "(void) unused_variable;" idiom
recommended by GCC manual and already used in print_msg().
86 lines
2.4 KiB
C
86 lines
2.4 KiB
C
/*
|
|
* Copyright (C) 2022 be.storaged GmbH
|
|
*
|
|
* This file is part of libfaketime
|
|
*
|
|
* libfaketime is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License v2 as published by the
|
|
* Free Software Foundation.
|
|
*
|
|
* libfaketime is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License v2 along
|
|
* with the libfaketime; if not, write to the Free Software Foundation,
|
|
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <pthread.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <time.h>
|
|
#include <unistd.h>
|
|
|
|
static void print_msg(const char *msg) {
|
|
size_t out;
|
|
out = write(0, msg, strlen(msg));
|
|
(void) out; /* unused */
|
|
}
|
|
|
|
static void* actual_malloc(size_t size) {
|
|
/* We would like to use "the real malloc", but cannot. Thus, this
|
|
* implements a trivial, allocate-only bump allocator to make things
|
|
* work.
|
|
*/
|
|
static char memory_arena[16 << 20];
|
|
static size_t allocated_index = 0;
|
|
|
|
void *result = &memory_arena[allocated_index];
|
|
|
|
allocated_index += size;
|
|
/* align to a multiple of 8 bytes */
|
|
allocated_index = (allocated_index + 7) / 8 * 8;
|
|
|
|
if (allocated_index >= sizeof(memory_arena)) {
|
|
print_msg("libmallocintercept is out of memory!");
|
|
abort();
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static void poke_faketime(void) {
|
|
#ifdef FAIL_PRE_INIT_CALLS
|
|
/* To complicate things for libfaketime, this calls clock_gettime()
|
|
* while holding a lock. This should simulate problems that occurred
|
|
* with address sanitizer.
|
|
*/
|
|
static pthread_mutex_t time_mutex = PTHREAD_MUTEX_INITIALIZER;
|
|
struct timespec timespec;
|
|
|
|
pthread_mutex_lock(&time_mutex);
|
|
clock_gettime(CLOCK_REALTIME, ×pec);
|
|
pthread_mutex_unlock(&time_mutex);
|
|
#else
|
|
print_msg("FAIL_PRE_INIT_CALLS not defined, skipping poke_faketime() ");
|
|
#endif
|
|
}
|
|
|
|
void *malloc(size_t size) {
|
|
print_msg("Called malloc() from libmallocintercept...");
|
|
poke_faketime();
|
|
print_msg("successfully\n");
|
|
return actual_malloc(size);
|
|
}
|
|
|
|
void free(void *ptr) {
|
|
(void) ptr; /* unused */
|
|
print_msg("Called free() on from libmallocintercept...");
|
|
poke_faketime();
|
|
print_msg("successfully\n");
|
|
|
|
/* We cannot actually free memory */
|
|
}
|