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-rw-r--r--htl/pt-create.c246
1 files changed, 246 insertions, 0 deletions
diff --git a/htl/pt-create.c b/htl/pt-create.c
new file mode 100644
index 0000000..f5c06ff
--- /dev/null
+++ b/htl/pt-create.c
@@ -0,0 +1,246 @@
+/* Thread creation.
+ Copyright (C) 2000-2018 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#include <assert.h>
+#include <errno.h>
+#include <pthread.h>
+#include <signal.h>
+#include <resolv.h>
+
+#include <atomic.h>
+#include <hurd/resource.h>
+
+#include <pt-internal.h>
+
+#if IS_IN (libpthread)
+# include <ctype.h>
+#endif
+#ifdef HAVE_USELOCALE
+# include <locale.h>
+#endif
+
+/* The total number of pthreads currently active. This is defined
+ here since it would be really stupid to have a threads-using
+ program that doesn't call `pthread_create'. */
+unsigned int __pthread_total;
+
+
+/* The entry-point for new threads. */
+static void
+entry_point (struct __pthread *self, void *(*start_routine) (void *), void *arg)
+{
+ ___pthread_self = self;
+ __resp = &self->res_state;
+
+#if IS_IN (libpthread)
+ /* Initialize pointers to locale data. */
+ __ctype_init ();
+#endif
+#ifdef HAVE_USELOCALE
+ /* A fresh thread needs to be bound to the global locale. */
+ uselocale (LC_GLOBAL_LOCALE);
+#endif
+
+ __pthread_startup ();
+
+ pthread_exit (start_routine (arg));
+}
+
+/* Create a thread with attributes given by ATTR, executing
+ START_ROUTINE with argument ARG. */
+int
+pthread_create (pthread_t * thread, const pthread_attr_t * attr,
+ void *(*start_routine) (void *), void *arg)
+{
+ int err;
+ struct __pthread *pthread;
+
+ err = __pthread_create_internal (&pthread, attr, start_routine, arg);
+ if (!err)
+ *thread = pthread->thread;
+ else if (err == ENOMEM)
+ err = EAGAIN;
+
+ return err;
+}
+
+/* Internal version of pthread_create. See comment in
+ pt-internal.h. */
+int
+__pthread_create_internal (struct __pthread **thread,
+ const pthread_attr_t * attr,
+ void *(*start_routine) (void *), void *arg)
+{
+ int err;
+ struct __pthread *pthread;
+ const struct __pthread_attr *setup;
+ sigset_t sigset;
+ size_t stacksize;
+
+ /* Allocate a new thread structure. */
+ err = __pthread_alloc (&pthread);
+ if (err)
+ goto failed;
+
+ /* Use the default attributes if ATTR is NULL. */
+ setup = attr ? attr : &__pthread_default_attr;
+
+ stacksize = setup->__stacksize;
+ if (stacksize == 0)
+ {
+ struct rlimit rlim;
+ __getrlimit (RLIMIT_STACK, &rlim);
+ if (rlim.rlim_cur != RLIM_INFINITY)
+ stacksize = rlim.rlim_cur;
+ if (stacksize == 0)
+ stacksize = PTHREAD_STACK_DEFAULT;
+ }
+
+ /* Initialize the thread state. */
+ pthread->state = (setup->__detachstate == PTHREAD_CREATE_DETACHED
+ ? PTHREAD_DETACHED : PTHREAD_JOINABLE);
+
+ if (setup->__stackaddr)
+ {
+ pthread->stackaddr = setup->__stackaddr;
+
+ /* If the user supplied a stack, it is not our responsibility to
+ setup a stack guard. */
+ pthread->guardsize = 0;
+ pthread->stack = 0;
+ }
+ else
+ {
+ /* Allocate a stack. */
+ err = __pthread_stack_alloc (&pthread->stackaddr,
+ ((setup->__guardsize + __vm_page_size - 1)
+ / __vm_page_size) * __vm_page_size
+ + stacksize);
+ if (err)
+ goto failed_stack_alloc;
+
+ pthread->guardsize = setup->__guardsize;
+ pthread->stack = 1;
+ }
+
+ pthread->stacksize = stacksize;
+
+ /* Allocate the kernel thread and other required resources. */
+ err = __pthread_thread_alloc (pthread);
+ if (err)
+ goto failed_thread_alloc;
+
+ pthread->tcb = _dl_allocate_tls (NULL);
+ if (pthread->tcb == NULL)
+ {
+ err = ENOMEM;
+ goto failed_thread_tls_alloc;
+ }
+ pthread->tcb->tcb = pthread->tcb;
+
+ /* And initialize the rest of the machine context. This may include
+ additional machine- and system-specific initializations that
+ prove convenient. */
+ err = __pthread_setup (pthread, entry_point, start_routine, arg);
+ if (err)
+ goto failed_setup;
+
+ /* Initialize the system-specific signal state for the new
+ thread. */
+ err = __pthread_sigstate_init (pthread);
+ if (err)
+ goto failed_sigstate;
+
+ /* If the new thread is joinable, add a reference for the caller. */
+ if (pthread->state == PTHREAD_JOINABLE)
+ pthread->nr_refs++;
+
+ /* Set the new thread's signal mask and set the pending signals to
+ empty. POSIX says: "The signal mask shall be inherited from the
+ creating thread. The set of signals pending for the new thread
+ shall be empty." If the currnet thread is not a pthread then we
+ just inherit the process' sigmask. */
+ if (__pthread_num_threads == 1)
+ err = sigprocmask (0, 0, &sigset);
+ else
+ err = __pthread_sigstate (_pthread_self (), 0, 0, &sigset, 0);
+ assert_perror (err);
+
+ err = __pthread_sigstate (pthread, SIG_SETMASK, &sigset, 0, 1);
+ assert_perror (err);
+
+ /* Increase the total number of threads. We do this before actually
+ starting the new thread, since the new thread might immediately
+ call `pthread_exit' which decreases the number of threads and
+ calls `exit' if the number of threads reaches zero. Increasing
+ the number of threads from within the new thread isn't an option
+ since this thread might return and call `pthread_exit' before the
+ new thread runs. */
+ atomic_increment (&__pthread_total);
+
+ /* Store a pointer to this thread in the thread ID lookup table. We
+ could use __thread_setid, however, we only lock for reading as no
+ other thread should be using this entry (we also assume that the
+ store is atomic). */
+ __pthread_rwlock_rdlock (&__pthread_threads_lock);
+ __pthread_threads[pthread->thread - 1] = pthread;
+ __pthread_rwlock_unlock (&__pthread_threads_lock);
+
+ /* At this point it is possible to guess our pthread ID. We have to
+ make sure that all functions taking a pthread_t argument can
+ handle the fact that this thread isn't really running yet. Since
+ the new thread might be passed its ID through pthread_create (to
+ avoid calling pthread_self), read it before starting the thread. */
+ *thread = pthread;
+
+ /* Schedule the new thread. */
+ err = __pthread_thread_start (pthread);
+ if (err)
+ goto failed_starting;
+
+
+ return 0;
+
+failed_starting:
+ /* If joinable, a reference was added for the caller. */
+ if (pthread->state == PTHREAD_JOINABLE)
+ __pthread_dealloc (pthread);
+
+ __pthread_setid (pthread->thread, NULL);
+ atomic_decrement (&__pthread_total);
+failed_sigstate:
+ __pthread_sigstate_destroy (pthread);
+failed_setup:
+ _dl_deallocate_tls (pthread->tcb, 1);
+ pthread->tcb = NULL;
+failed_thread_tls_alloc:
+ __pthread_thread_terminate (pthread);
+
+ /* __pthread_thread_terminate has taken care of deallocating the stack and
+ the thread structure. */
+ goto failed;
+failed_thread_alloc:
+ if (pthread->stack)
+ __pthread_stack_dealloc (pthread->stackaddr,
+ ((setup->__guardsize + __vm_page_size - 1)
+ / __vm_page_size) * __vm_page_size + stacksize);
+failed_stack_alloc:
+ __pthread_dealloc (pthread);
+failed:
+ return err;
+}
generated by cgit v1.1 at 2024-12-04 09:27:53 +0000