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#include "pthread_impl.h"
static void dummy_0()
{
}
weak_alias(dummy_0, __rsyscall_lock);
weak_alias(dummy_0, __rsyscall_unlock);
static void dummy_1(pthread_t self)
{
}
weak_alias(dummy_1, __pthread_tsd_run_dtors);
weak_alias(dummy_1, __sigtimer_handler);
#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;
if (cb->__next) longjmp((void *)cb->__next->__jb, 1);
self = pthread_self();
LOCK(&self->exitlock);
__pthread_tsd_run_dtors(self);
/* Mark this thread dead before decrementing count */
self->dead = 1;
if (!a_fetch_add(&libc.threads_minus_1, -1))
exit(0);
if (self->detached && self->map_base) {
__syscall(SYS_rt_sigprocmask, SIG_BLOCK, (long)(uint64_t[1]){-1},0,8);
__unmapself(self->map_base, self->map_size);
}
__syscall(SYS_exit, 0);
}
static void docancel(struct pthread *self)
{
struct __ptcb cb = { .__next = self->cancelbuf };
self->canceldisable = 1;
self->cancelasync = 0;
__pthread_unwind_next(&cb);
}
static void cancel_handler(int sig, siginfo_t *si, void *ctx)
{
struct pthread *self = __pthread_self();
if (si->si_code == SI_TIMER) __sigtimer_handler(self);
if (self->cancel && !self->canceldisable &&
(self->cancelasync || (self->cancelpoint==1 && PC_AT_SYS(ctx))))
docancel(self);
}
static void cancelpt(int x)
{
struct pthread *self = __pthread_self();
switch (x) {
case 1:
self->cancelpoint++;
case 0:
if (self->cancel && self->cancelpoint==1 && !self->canceldisable)
docancel(self);
break;
case -1:
self->cancelpoint--;
break;
default:
self->canceldisable += x;
}
}
static void init_threads()
{
struct sigaction sa = { .sa_flags = SA_SIGINFO | SA_RESTART };
libc.lock = __lock;
libc.lockfile = __lockfile;
libc.cancelpt = cancelpt;
sigemptyset(&sa.sa_mask);
sa.sa_sigaction = cancel_handler;
__libc_sigaction(SIGCANCEL, &sa, 0);
sigaddset(&sa.sa_mask, SIGSYSCALL);
sigaddset(&sa.sa_mask, SIGCANCEL);
__libc_sigprocmask(SIG_UNBLOCK, &sa.sa_mask, 0);
}
static int start(void *p)
{
struct pthread *self = p;
if (self->unblock_cancel) {
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGCANCEL);
__libc_sigprocmask(SIG_UNBLOCK, &set, 0);
}
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)
{
static int init;
int ret;
size_t size, guard;
struct pthread *self = pthread_self(), *new;
unsigned char *map, *stack, *tsd;
const pthread_attr_t default_attr = { 0 };
if (!self) return ENOSYS;
if (!init && ++init) init_threads();
if (!attr) attr = &default_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;
new->detached = attr->_a_detach;
new->attr = *attr;
new->unblock_cancel = self->cancel;
new->result = PTHREAD_CANCELED;
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();
self->result = result;
docancel(self);
}
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