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| | #include "pthread_impl.h"
static void dummy_0()
{
}
weak_alias(dummy_0, __rsyscall_lock);
weak_alias(dummy_0, __rsyscall_unlock);
weak_alias(dummy_0, __pthread_tsd_run_dtors);
#ifdef __pthread_unwind_next
#undef __pthread_unwind_next
#define __pthread_unwind_next __pthread_unwind_next_3
#endif
void __pthread_unwind_next(struct __ptcb *cb)
{
pthread_t self = pthread_self();
int n;
if (cb->__next) {
self->cancelbuf = cb->__next->__next;
longjmp((void *)cb->__next->__jb, 1);
}
LOCK(&self->exitlock);
__pthread_tsd_run_dtors();
/* Mark this thread dead before decrementing count */
self->dead = 1;
do n = libc.threads_minus_1;
while (n && a_cas(&libc.threads_minus_1, n, n-1)!=n);
if (!n) exit(0);
if (self->detached && self->map_base) {
__syscall(SYS_rt_sigprocmask, SIG_BLOCK, (uint64_t[]){-1},0,8);
__unmapself(self->map_base, self->map_size);
}
__syscall(SYS_exit, 0);
}
static int start(void *p)
{
struct pthread *self = p;
if (self->unblock_cancel)
__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, SIGPT_SET, 0, 8);
pthread_exit(self->start(self->start_arg));
return 0;
}
int __uniclone(void *, int (*)(), void *);
#define ROUND(x) (((x)+PAGE_SIZE-1)&-PAGE_SIZE)
/* pthread_key_create.c overrides this */
static const size_t dummy = 0;
weak_alias(dummy, __pthread_tsd_size);
int pthread_create(pthread_t *res, const pthread_attr_t *attr, void *(*entry)(void *), void *arg)
{
int ret;
size_t size = DEFAULT_STACK_SIZE + DEFAULT_GUARD_SIZE;
size_t guard = DEFAULT_GUARD_SIZE;
struct pthread *self = pthread_self(), *new;
unsigned char *map, *stack, *tsd;
if (!self) return ENOSYS;
if (!libc.threaded) {
__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, SIGPT_SET, 0, 8);
libc.threaded = 1;
}
if (attr) {
guard = ROUND(attr->_a_guardsize + DEFAULT_GUARD_SIZE);
size = guard + ROUND(attr->_a_stacksize + DEFAULT_STACK_SIZE);
}
size += __pthread_tsd_size;
map = mmap(0, size, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANON, -1, 0);
if (!map) return EAGAIN;
if (guard) mprotect(map, guard, PROT_NONE);
tsd = map + size - __pthread_tsd_size;
new = (void *)(tsd - sizeof *new - PAGE_SIZE%sizeof *new);
new->map_base = map;
new->map_size = size;
new->pid = self->pid;
new->errno_ptr = &new->errno_val;
new->start = entry;
new->start_arg = arg;
new->self = new;
new->tsd = (void *)tsd;
if (attr) new->detached = attr->_a_detach;
new->unblock_cancel = self->cancel;
memcpy(new->tlsdesc, self->tlsdesc, sizeof new->tlsdesc);
new->tlsdesc[1] = (uintptr_t)new;
stack = (void *)((uintptr_t)new-1 & ~(uintptr_t)15);
__rsyscall_lock();
a_inc(&libc.threads_minus_1);
ret = __uniclone(stack, start, new);
__rsyscall_unlock();
if (ret < 0) {
a_dec(&libc.threads_minus_1);
munmap(map, size);
return EAGAIN;
}
*res = new;
return 0;
}
void pthread_exit(void *result)
{
struct pthread *self = pthread_self();
struct __ptcb cb = { .__next = self->cancelbuf };
self->result = result;
__pthread_unwind_next(&cb);
}
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