#include <stdlib.h>
#include <stdarg.h>
#include "pthread_impl.h"
-#include "libc.h"
+#include "dynlink.h"
+#include "atomic.h"
+
+#define malloc __libc_malloc
+#define calloc __libc_calloc
+#define realloc __libc_realloc
+#define free __libc_free
char *dlerror()
{
return s;
}
+/* Atomic singly-linked list, used to store list of thread-local dlerror
+ * buffers for deferred free. They cannot be freed at thread exit time
+ * because, by the time it's known they can be freed, the exiting thread
+ * is in a highly restrictive context where it cannot call (even the
+ * libc-internal) free. It also can't take locks; thus the atomic list. */
+
+static void *volatile freebuf_queue;
+
void __dl_thread_cleanup(void)
{
pthread_t self = __pthread_self();
- if (self->dlerror_buf != (void *)-1)
- free(self->dlerror_buf);
+ if (!self->dlerror_buf || self->dlerror_buf == (void *)-1)
+ return;
+ void *h;
+ do {
+ h = freebuf_queue;
+ *(void **)self->dlerror_buf = h;
+ } while (a_cas_p(&freebuf_queue, h, self->dlerror_buf) != h);
}
-__attribute__((__visibility__("hidden")))
-void __dl_vseterr(const char *fmt, va_list ap)
+hidden void __dl_vseterr(const char *fmt, va_list ap)
{
+ void **q;
+ do q = freebuf_queue;
+ while (q && a_cas_p(&freebuf_queue, q, 0) != q);
+
+ 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) {
self->dlerror_flag = 1;
}
-__attribute__((__visibility__("hidden")))
-void __dl_seterr(const char *fmt, ...)
+hidden void __dl_seterr(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
va_end(ap);
}
-__attribute__((__visibility__("hidden")))
-int __dl_invalid_handle(void *);
-
static int stub_invalid_handle(void *h)
{
__dl_seterr("Invalid library handle %p", (void *)h);