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| | #include <dlfcn.h>
#include <stdlib.h>
#include <stdarg.h>
#include "pthread_impl.h"
#include "dynlink.h"
#include "lock.h"
#include "fork_impl.h"
#define malloc __libc_malloc
#define calloc __libc_calloc
#define realloc __libc_realloc
#define free __libc_free
char *dlerror()
{
pthread_t self = __pthread_self();
if (!self->dlerror_flag) return 0;
self->dlerror_flag = 0;
char *s = self->dlerror_buf;
if (s == (void *)-1)
return "Dynamic linker failed to allocate memory for error message";
else
return s;
}
static volatile int freebuf_queue_lock[1];
static void **freebuf_queue;
volatile int *const __dlerror_lockptr = freebuf_queue_lock;
void __dl_thread_cleanup(void)
{
pthread_t self = __pthread_self();
if (self->dlerror_buf && self->dlerror_buf != (void *)-1) {
LOCK(freebuf_queue_lock);
void **p = (void **)self->dlerror_buf;
*p = freebuf_queue;
freebuf_queue = p;
UNLOCK(freebuf_queue_lock);
}
}
hidden void __dl_vseterr(const char *fmt, va_list ap)
{
LOCK(freebuf_queue_lock);
void **q = freebuf_queue;
freebuf_queue = 0;
UNLOCK(freebuf_queue_lock);
while (q) {
void **p = *q;
free(q);
q = p;
}
va_list ap2;
va_copy(ap2, ap);
pthread_t self = __pthread_self();
if (self->dlerror_buf != (void *)-1)
free(self->dlerror_buf);
size_t len = vsnprintf(0, 0, fmt, ap2);
if (len < sizeof(void *)) len = sizeof(void *);
va_end(ap2);
char *buf = malloc(len+1);
if (buf) {
vsnprintf(buf, len+1, fmt, ap);
} else {
buf = (void *)-1;
}
self->dlerror_buf = buf;
self->dlerror_flag = 1;
}
hidden void __dl_seterr(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
__dl_vseterr(fmt, ap);
va_end(ap);
}
static int stub_invalid_handle(void *h)
{
__dl_seterr("Invalid library handle %p", (void *)h);
return 1;
}
weak_alias(stub_invalid_handle, __dl_invalid_handle);
|