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authorMike Frysinger <vapier@gentoo.org>2006-01-31 05:05:15 +0000
committerMike Frysinger <vapier@gentoo.org>2006-01-31 05:05:15 +0000
commitcccc549ced940c85039c8ce263c8bb571f244afd (patch)
treeef77a870db7211ad6f511867fc56ee1a1a8b4c18 /libpthread/linuxthreads/pthread.c
parente73b1211737842732951f9b9049294ef732e1ef0 (diff)
initial import of latest linuxthreads
Diffstat (limited to 'libpthread/linuxthreads/pthread.c')
-rw-r--r--libpthread/linuxthreads/pthread.c1379
1 files changed, 1379 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/pthread.c b/libpthread/linuxthreads/pthread.c
new file mode 100644
index 000000000..21656fe64
--- /dev/null
+++ b/libpthread/linuxthreads/pthread.c
@@ -0,0 +1,1379 @@
+
+/* Linuxthreads - a simple clone()-based implementation of Posix */
+/* threads for Linux. */
+/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
+/* */
+/* This program 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. */
+/* */
+/* This program 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. */
+
+/* Thread creation, initialization, and basic low-level routines */
+
+#include <errno.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <sys/resource.h>
+#include <sys/time.h>
+#include "pthread.h"
+#include "internals.h"
+#include "spinlock.h"
+#include "restart.h"
+#include "smp.h"
+#include <not-cancel.h>
+
+#define __clone clone
+
+/* Sanity check. */
+#if !defined __SIGRTMIN || (__SIGRTMAX - __SIGRTMIN) < 3
+# error "This must not happen"
+#endif
+
+/* mods for uClibc: __libc_sigaction is not in any standard headers */
+extern int __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact);
+extern int __cxa_atexit (void (*func) (void *), void *arg, void *d);
+
+#if !(USE_TLS && HAVE___THREAD)
+/* These variables are used by the setup code. */
+extern int _errno;
+extern int _h_errno;
+
+/* We need the global/static resolver state here. */
+# include <resolv.h>
+# undef _res
+
+extern struct __res_state _res;
+#endif
+
+#ifdef USE_TLS
+
+/* We need only a few variables. */
+#define manager_thread __pthread_manager_threadp
+pthread_descr __pthread_manager_threadp attribute_hidden;
+
+#else
+
+/* Descriptor of the initial thread */
+
+struct _pthread_descr_struct __pthread_initial_thread = {
+ .p_header.data.self = &__pthread_initial_thread,
+ .p_nextlive = &__pthread_initial_thread,
+ .p_prevlive = &__pthread_initial_thread,
+ .p_tid = PTHREAD_THREADS_MAX,
+ .p_lock = &__pthread_handles[0].h_lock,
+ .p_start_args = PTHREAD_START_ARGS_INITIALIZER(NULL),
+#if !(USE_TLS && HAVE___THREAD)
+ .p_errnop = &_errno,
+ .p_h_errnop = &_h_errno,
+ .p_resp = &_res,
+#endif
+ .p_userstack = 1,
+ .p_resume_count = __ATOMIC_INITIALIZER,
+ .p_alloca_cutoff = __MAX_ALLOCA_CUTOFF
+};
+
+/* Descriptor of the manager thread; none of this is used but the error
+ variables, the p_pid and p_priority fields,
+ and the address for identification. */
+
+#define manager_thread (&__pthread_manager_thread)
+struct _pthread_descr_struct __pthread_manager_thread = {
+ .p_header.data.self = &__pthread_manager_thread,
+ .p_header.data.multiple_threads = 1,
+ .p_lock = &__pthread_handles[1].h_lock,
+ .p_start_args = PTHREAD_START_ARGS_INITIALIZER(__pthread_manager),
+#if !(USE_TLS && HAVE___THREAD)
+ .p_errnop = &__pthread_manager_thread.p_errno,
+#endif
+ .p_nr = 1,
+ .p_resume_count = __ATOMIC_INITIALIZER,
+ .p_alloca_cutoff = PTHREAD_STACK_MIN / 4
+};
+#endif
+
+/* Pointer to the main thread (the father of the thread manager thread) */
+/* Originally, this is the initial thread, but this changes after fork() */
+
+#ifdef USE_TLS
+pthread_descr __pthread_main_thread;
+#else
+pthread_descr __pthread_main_thread = &__pthread_initial_thread;
+#endif
+
+/* Limit between the stack of the initial thread (above) and the
+ stacks of other threads (below). Aligned on a STACK_SIZE boundary. */
+
+char *__pthread_initial_thread_bos;
+
+/* File descriptor for sending requests to the thread manager. */
+/* Initially -1, meaning that the thread manager is not running. */
+
+int __pthread_manager_request = -1;
+
+int __pthread_multiple_threads attribute_hidden;
+
+/* Other end of the pipe for sending requests to the thread manager. */
+
+int __pthread_manager_reader;
+
+/* Limits of the thread manager stack */
+
+char *__pthread_manager_thread_bos;
+char *__pthread_manager_thread_tos;
+
+/* For process-wide exit() */
+
+int __pthread_exit_requested;
+int __pthread_exit_code;
+
+/* Maximum stack size. */
+size_t __pthread_max_stacksize;
+
+/* Nozero if the machine has more than one processor. */
+int __pthread_smp_kernel;
+
+
+#if !__ASSUME_REALTIME_SIGNALS
+/* Pointers that select new or old suspend/resume functions
+ based on availability of rt signals. */
+
+void (*__pthread_restart)(pthread_descr) = __pthread_restart_old;
+void (*__pthread_suspend)(pthread_descr) = __pthread_suspend_old;
+int (*__pthread_timedsuspend)(pthread_descr, const struct timespec *) = __pthread_timedsuspend_old;
+#endif /* __ASSUME_REALTIME_SIGNALS */
+
+/* Communicate relevant LinuxThreads constants to gdb */
+
+const int __pthread_threads_max = PTHREAD_THREADS_MAX;
+const int __pthread_sizeof_handle = sizeof(struct pthread_handle_struct);
+const int __pthread_offsetof_descr = offsetof(struct pthread_handle_struct,
+ h_descr);
+const int __pthread_offsetof_pid = offsetof(struct _pthread_descr_struct,
+ p_pid);
+const int __linuxthreads_pthread_sizeof_descr
+ = sizeof(struct _pthread_descr_struct);
+
+const int __linuxthreads_initial_report_events;
+
+const char __linuxthreads_version[] = VERSION;
+
+/* Forward declarations */
+
+static void pthread_onexit_process(int retcode, void *arg);
+#ifndef HAVE_Z_NODELETE
+static void pthread_atexit_process(void *arg, int retcode);
+static void pthread_atexit_retcode(void *arg, int retcode);
+#endif
+static void pthread_handle_sigcancel(int sig);
+static void pthread_handle_sigrestart(int sig);
+static void pthread_handle_sigdebug(int sig);
+
+/* Signal numbers used for the communication.
+ In these variables we keep track of the used variables. If the
+ platform does not support any real-time signals we will define the
+ values to some unreasonable value which will signal failing of all
+ the functions below. */
+int __pthread_sig_restart = __SIGRTMIN;
+int __pthread_sig_cancel = __SIGRTMIN + 1;
+int __pthread_sig_debug = __SIGRTMIN + 2;
+
+extern int __libc_current_sigrtmin_private (void);
+
+#if !__ASSUME_REALTIME_SIGNALS
+static int rtsigs_initialized;
+
+static void
+init_rtsigs (void)
+{
+ if (rtsigs_initialized)
+ return;
+
+ if (__libc_current_sigrtmin_private () == -1)
+ {
+ __pthread_sig_restart = SIGUSR1;
+ __pthread_sig_cancel = SIGUSR2;
+ __pthread_sig_debug = 0;
+ }
+ else
+ {
+ __pthread_restart = __pthread_restart_new;
+ __pthread_suspend = __pthread_wait_for_restart_signal;
+ __pthread_timedsuspend = __pthread_timedsuspend_new;
+ }
+
+ rtsigs_initialized = 1;
+}
+#endif
+
+
+/* Initialize the pthread library.
+ Initialization is split in two functions:
+ - a constructor function that blocks the __pthread_sig_restart signal
+ (must do this very early, since the program could capture the signal
+ mask with e.g. sigsetjmp before creating the first thread);
+ - a regular function called from pthread_create when needed. */
+
+static void pthread_initialize(void) __attribute__((constructor));
+
+#ifndef HAVE_Z_NODELETE
+extern void *__dso_handle __attribute__ ((weak));
+#endif
+
+
+#if defined USE_TLS && !defined SHARED
+extern void __libc_setup_tls (size_t tcbsize, size_t tcbalign);
+#endif
+
+struct pthread_functions __pthread_functions =
+ {
+#if !(USE_TLS && HAVE___THREAD)
+ .ptr_pthread_internal_tsd_set = __pthread_internal_tsd_set,
+ .ptr_pthread_internal_tsd_get = __pthread_internal_tsd_get,
+ .ptr_pthread_internal_tsd_address = __pthread_internal_tsd_address,
+#endif
+ .ptr_pthread_fork = __pthread_fork,
+ .ptr_pthread_attr_destroy = __pthread_attr_destroy,
+ .ptr___pthread_attr_init = __pthread_attr_init,
+ .ptr_pthread_attr_getdetachstate = __pthread_attr_getdetachstate,
+ .ptr_pthread_attr_setdetachstate = __pthread_attr_setdetachstate,
+ .ptr_pthread_attr_getinheritsched = __pthread_attr_getinheritsched,
+ .ptr_pthread_attr_setinheritsched = __pthread_attr_setinheritsched,
+ .ptr_pthread_attr_getschedparam = __pthread_attr_getschedparam,
+ .ptr_pthread_attr_setschedparam = __pthread_attr_setschedparam,
+ .ptr_pthread_attr_getschedpolicy = __pthread_attr_getschedpolicy,
+ .ptr_pthread_attr_setschedpolicy = __pthread_attr_setschedpolicy,
+ .ptr_pthread_attr_getscope = __pthread_attr_getscope,
+ .ptr_pthread_attr_setscope = __pthread_attr_setscope,
+ .ptr_pthread_condattr_destroy = __pthread_condattr_destroy,
+ .ptr_pthread_condattr_init = __pthread_condattr_init,
+ .ptr_pthread_cond_broadcast = __pthread_cond_broadcast,
+ .ptr_pthread_cond_destroy = __pthread_cond_destroy,
+ .ptr_pthread_cond_init = __pthread_cond_init,
+ .ptr_pthread_cond_signal = __pthread_cond_signal,
+ .ptr_pthread_cond_wait = __pthread_cond_wait,
+ .ptr_pthread_cond_timedwait = __pthread_cond_timedwait,
+ .ptr_pthread_equal = __pthread_equal,
+ .ptr___pthread_exit = __pthread_exit,
+ .ptr_pthread_getschedparam = __pthread_getschedparam,
+ .ptr_pthread_setschedparam = __pthread_setschedparam,
+ .ptr_pthread_mutex_destroy = __pthread_mutex_destroy,
+ .ptr_pthread_mutex_init = __pthread_mutex_init,
+ .ptr_pthread_mutex_lock = __pthread_mutex_lock,
+ .ptr_pthread_mutex_trylock = __pthread_mutex_trylock,
+ .ptr_pthread_mutex_unlock = __pthread_mutex_unlock,
+ .ptr_pthread_self = __pthread_self,
+ .ptr_pthread_setcancelstate = __pthread_setcancelstate,
+ .ptr_pthread_setcanceltype = __pthread_setcanceltype,
+ .ptr_pthread_do_exit = __pthread_do_exit,
+ .ptr_pthread_thread_self = __pthread_thread_self,
+ .ptr_pthread_cleanup_upto = __pthread_cleanup_upto,
+ .ptr_pthread_sigaction = __pthread_sigaction,
+ .ptr_pthread_sigwait = __pthread_sigwait,
+ .ptr_pthread_raise = __pthread_raise,
+ .ptr__pthread_cleanup_push = _pthread_cleanup_push,
+ .ptr__pthread_cleanup_pop = _pthread_cleanup_pop
+ };
+#ifdef SHARED
+# define ptr_pthread_functions &__pthread_functions
+#else
+# define ptr_pthread_functions NULL
+#endif
+
+static int *__libc_multiple_threads_ptr;
+
+/* Do some minimal initialization which has to be done during the
+ startup of the C library. */
+void
+__pthread_initialize_minimal(void)
+{
+#ifdef USE_TLS
+ pthread_descr self;
+
+ /* First of all init __pthread_handles[0] and [1] if needed. */
+# if __LT_SPINLOCK_INIT != 0
+ __pthread_handles[0].h_lock = __LOCK_INITIALIZER;
+ __pthread_handles[1].h_lock = __LOCK_INITIALIZER;
+# endif
+# ifndef SHARED
+ /* Unlike in the dynamically linked case the dynamic linker has not
+ taken care of initializing the TLS data structures. */
+ __libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN);
+# elif !USE___THREAD
+ if (__builtin_expect (GL(dl_tls_dtv_slotinfo_list) == NULL, 0))
+ {
+ tcbhead_t *tcbp;
+
+ /* There is no actual TLS being used, so the thread register
+ was not initialized in the dynamic linker. */
+
+ /* We need to install special hooks so that the malloc and memalign
+ calls in _dl_tls_setup and _dl_allocate_tls won't cause full
+ malloc initialization that will try to set up its thread state. */
+
+ extern void __libc_malloc_pthread_startup (bool first_time);
+ __libc_malloc_pthread_startup (true);
+
+ if (__builtin_expect (_dl_tls_setup (), 0)
+ || __builtin_expect ((tcbp = _dl_allocate_tls (NULL)) == NULL, 0))
+ {
+ static const char msg[] = "\
+cannot allocate TLS data structures for initial thread\n";
+ TEMP_FAILURE_RETRY (write_not_cancel (STDERR_FILENO,
+ msg, sizeof msg - 1));
+ abort ();
+ }
+ const char *lossage = TLS_INIT_TP (tcbp, 0);
+ if (__builtin_expect (lossage != NULL, 0))
+ {
+ static const char msg[] = "cannot set up thread-local storage: ";
+ const char nl = '\n';
+ TEMP_FAILURE_RETRY (write_not_cancel (STDERR_FILENO,
+ msg, sizeof msg - 1));
+ TEMP_FAILURE_RETRY (write_not_cancel (STDERR_FILENO,
+ lossage, strlen (lossage)));
+ TEMP_FAILURE_RETRY (write_not_cancel (STDERR_FILENO, &nl, 1));
+ }
+
+ /* Though it was allocated with libc's malloc, that was done without
+ the user's __malloc_hook installed. A later realloc that uses
+ the hooks might not work with that block from the plain malloc.
+ So we record this block as unfreeable just as the dynamic linker
+ does when it allocates the DTV before the libc malloc exists. */
+ GL(dl_initial_dtv) = GET_DTV (tcbp);
+
+ __libc_malloc_pthread_startup (false);
+ }
+# endif
+
+ self = THREAD_SELF;
+
+ /* The memory for the thread descriptor was allocated elsewhere as
+ part of the TLS allocation. We have to initialize the data
+ structure by hand. This initialization must mirror the struct
+ definition above. */
+ self->p_nextlive = self->p_prevlive = self;
+ self->p_tid = PTHREAD_THREADS_MAX;
+ self->p_lock = &__pthread_handles[0].h_lock;
+# ifndef HAVE___THREAD
+ self->p_errnop = &_errno;
+ self->p_h_errnop = &_h_errno;
+# endif
+ /* self->p_start_args need not be initialized, it's all zero. */
+ self->p_userstack = 1;
+# if __LT_SPINLOCK_INIT != 0
+ self->p_resume_count = (struct pthread_atomic) __ATOMIC_INITIALIZER;
+# endif
+ self->p_alloca_cutoff = __MAX_ALLOCA_CUTOFF;
+
+ /* Another variable which points to the thread descriptor. */
+ __pthread_main_thread = self;
+
+ /* And fill in the pointer the the thread __pthread_handles array. */
+ __pthread_handles[0].h_descr = self;
+
+#else /* USE_TLS */
+
+ /* First of all init __pthread_handles[0] and [1]. */
+# if __LT_SPINLOCK_INIT != 0
+ __pthread_handles[0].h_lock = __LOCK_INITIALIZER;
+ __pthread_handles[1].h_lock = __LOCK_INITIALIZER;
+# endif
+ __pthread_handles[0].h_descr = &__pthread_initial_thread;
+ __pthread_handles[1].h_descr = &__pthread_manager_thread;
+
+ /* If we have special thread_self processing, initialize that for the
+ main thread now. */
+# ifdef INIT_THREAD_SELF
+ INIT_THREAD_SELF(&__pthread_initial_thread, 0);
+# endif
+#endif
+
+#if HP_TIMING_AVAIL
+# ifdef USE_TLS
+ self->p_cpuclock_offset = GL(dl_cpuclock_offset);
+# else
+ __pthread_initial_thread.p_cpuclock_offset = GL(dl_cpuclock_offset);
+# endif
+#endif
+
+ __libc_multiple_threads_ptr = __libc_pthread_init (ptr_pthread_functions);
+}
+
+
+void
+__pthread_init_max_stacksize(void)
+{
+ struct rlimit limit;
+ size_t max_stack;
+
+ getrlimit(RLIMIT_STACK, &limit);
+#ifdef FLOATING_STACKS
+ if (limit.rlim_cur == RLIM_INFINITY)
+ limit.rlim_cur = ARCH_STACK_MAX_SIZE;
+# ifdef NEED_SEPARATE_REGISTER_STACK
+ max_stack = limit.rlim_cur / 2;
+# else
+ max_stack = limit.rlim_cur;
+# endif
+#else
+ /* Play with the stack size limit to make sure that no stack ever grows
+ beyond STACK_SIZE minus one page (to act as a guard page). */
+# ifdef NEED_SEPARATE_REGISTER_STACK
+ /* STACK_SIZE bytes hold both the main stack and register backing
+ store. The rlimit value applies to each individually. */
+ max_stack = STACK_SIZE/2 - __getpagesize ();
+# else
+ max_stack = STACK_SIZE - __getpagesize();
+# endif
+ if (limit.rlim_cur > max_stack) {
+ limit.rlim_cur = max_stack;
+ setrlimit(RLIMIT_STACK, &limit);
+ }
+#endif
+ __pthread_max_stacksize = max_stack;
+ if (max_stack / 4 < __MAX_ALLOCA_CUTOFF)
+ {
+#ifdef USE_TLS
+ pthread_descr self = THREAD_SELF;
+ self->p_alloca_cutoff = max_stack / 4;
+#else
+ __pthread_initial_thread.p_alloca_cutoff = max_stack / 4;
+#endif
+ }
+}
+
+#ifdef SHARED
+# if USE___THREAD
+/* When using __thread for this, we do it in libc so as not
+ to give libpthread its own TLS segment just for this. */
+extern void **__libc_dl_error_tsd (void) __attribute__ ((const));
+# else
+static void ** __attribute__ ((const))
+__libc_dl_error_tsd (void)
+{
+ return &thread_self ()->p_libc_specific[_LIBC_TSD_KEY_DL_ERROR];
+}
+# endif
+#endif
+
+#ifdef USE_TLS
+static inline void __attribute__((always_inline))
+init_one_static_tls (pthread_descr descr, struct link_map *map)
+{
+# if TLS_TCB_AT_TP
+ dtv_t *dtv = GET_DTV (descr);
+ void *dest = (char *) descr - map->l_tls_offset;
+# elif TLS_DTV_AT_TP
+ dtv_t *dtv = GET_DTV ((pthread_descr) ((char *) descr + TLS_PRE_TCB_SIZE));
+ void *dest = (char *) descr + map->l_tls_offset + TLS_PRE_TCB_SIZE;
+# else
+# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+# endif
+
+ /* Fill in the DTV slot so that a later LD/GD access will find it. */
+ dtv[map->l_tls_modid].pointer.val = dest;
+ dtv[map->l_tls_modid].pointer.is_static = true;
+
+ /* Initialize the memory. */
+ memset (__mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
+ '\0', map->l_tls_blocksize - map->l_tls_initimage_size);
+}
+
+static void
+__pthread_init_static_tls (struct link_map *map)
+{
+ size_t i;
+
+ for (i = 0; i < PTHREAD_THREADS_MAX; ++i)
+ if (__pthread_handles[i].h_descr != NULL && i != 1)
+ {
+ __pthread_lock (&__pthread_handles[i].h_lock, NULL);
+ if (__pthread_handles[i].h_descr != NULL)
+ init_one_static_tls (__pthread_handles[i].h_descr, map);
+ __pthread_unlock (&__pthread_handles[i].h_lock);
+ }
+}
+#endif
+
+static void pthread_initialize(void)
+{
+ struct sigaction sa;
+ sigset_t mask;
+
+ /* If already done (e.g. by a constructor called earlier!), bail out */
+ if (__pthread_initial_thread_bos != NULL) return;
+#ifdef TEST_FOR_COMPARE_AND_SWAP
+ /* Test if compare-and-swap is available */
+ __pthread_has_cas = compare_and_swap_is_available();
+#endif
+#ifdef FLOATING_STACKS
+ /* We don't need to know the bottom of the stack. Give the pointer some
+ value to signal that initialization happened. */
+ __pthread_initial_thread_bos = (void *) -1l;
+#else
+ /* Determine stack size limits . */
+ __pthread_init_max_stacksize ();
+# ifdef _STACK_GROWS_UP
+ /* The initial thread already has all the stack it needs */
+ __pthread_initial_thread_bos = (char *)
+ ((long)CURRENT_STACK_FRAME &~ (STACK_SIZE - 1));
+# else
+ /* For the initial stack, reserve at least STACK_SIZE bytes of stack
+ below the current stack address, and align that on a
+ STACK_SIZE boundary. */
+ __pthread_initial_thread_bos =
+ (char *)(((long)CURRENT_STACK_FRAME - 2 * STACK_SIZE) & ~(STACK_SIZE - 1));
+# endif
+#endif
+#ifdef USE_TLS
+ /* Update the descriptor for the initial thread. */
+ THREAD_SETMEM (((pthread_descr) NULL), p_pid, __getpid());
+# ifndef HAVE___THREAD
+ /* Likewise for the resolver state _res. */
+ THREAD_SETMEM (((pthread_descr) NULL), p_resp, &_res);
+# endif
+#else
+ /* Update the descriptor for the initial thread. */
+ __pthread_initial_thread.p_pid = __getpid();
+ /* Likewise for the resolver state _res. */
+ __pthread_initial_thread.p_resp = &_res;
+#endif
+#if !__ASSUME_REALTIME_SIGNALS
+ /* Initialize real-time signals. */
+ init_rtsigs ();
+#endif
+ /* Setup signal handlers for the initial thread.
+ Since signal handlers are shared between threads, these settings
+ will be inherited by all other threads. */
+ sa.sa_handler = pthread_handle_sigrestart;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+ __libc_sigaction(__pthread_sig_restart, &sa, NULL);
+ sa.sa_handler = pthread_handle_sigcancel;
+ sigaddset(&sa.sa_mask, __pthread_sig_restart);
+ // sa.sa_flags = 0;
+ __libc_sigaction(__pthread_sig_cancel, &sa, NULL);
+ if (__pthread_sig_debug > 0) {
+ sa.sa_handler = pthread_handle_sigdebug;
+ sigemptyset(&sa.sa_mask);
+ // sa.sa_flags = 0;
+ __libc_sigaction(__pthread_sig_debug, &sa, NULL);
+ }
+ /* Initially, block __pthread_sig_restart. Will be unblocked on demand. */
+ sigemptyset(&mask);
+ sigaddset(&mask, __pthread_sig_restart);
+ sigprocmask(SIG_BLOCK, &mask, NULL);
+ /* And unblock __pthread_sig_cancel if it has been blocked. */
+ sigdelset(&mask, __pthread_sig_restart);
+ sigaddset(&mask, __pthread_sig_cancel);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+ /* Register an exit function to kill all other threads. */
+ /* Do it early so that user-registered atexit functions are called
+ before pthread_*exit_process. */
+#ifndef HAVE_Z_NODELETE
+ if (__builtin_expect (&__dso_handle != NULL, 1))
+ __cxa_atexit ((void (*) (void *)) pthread_atexit_process, NULL,
+ __dso_handle);
+ else
+#endif
+ __on_exit (pthread_onexit_process, NULL);
+ /* How many processors. */
+ __pthread_smp_kernel = is_smp_system ();
+
+#ifdef SHARED
+ /* Transfer the old value from the dynamic linker's internal location. */
+ *__libc_dl_error_tsd () = *(*GL(dl_error_catch_tsd)) ();
+ GL(dl_error_catch_tsd) = &__libc_dl_error_tsd;
+
+ /* Make __rtld_lock_{,un}lock_recursive use pthread_mutex_{,un}lock,
+ keep the lock count from the ld.so implementation. */
+ GL(dl_rtld_lock_recursive) = (void *) __pthread_mutex_lock;
+ GL(dl_rtld_unlock_recursive) = (void *) __pthread_mutex_unlock;
+ unsigned int rtld_lock_count = GL(dl_load_lock).mutex.__m_count;
+ GL(dl_load_lock).mutex.__m_count = 0;
+ while (rtld_lock_count-- > 0)
+ __pthread_mutex_lock (&GL(dl_load_lock).mutex);
+#endif
+
+#ifdef USE_TLS
+ GL(dl_init_static_tls) = &__pthread_init_static_tls;
+#endif
+}
+
+void __pthread_initialize(void)
+{
+ pthread_initialize();
+}
+
+int __pthread_initialize_manager(void)
+{
+ int manager_pipe[2];
+ int pid;
+ struct pthread_request request;
+ int report_events;
+ pthread_descr mgr;
+#ifdef USE_TLS
+ tcbhead_t *tcbp;
+#endif
+
+ __pthread_multiple_threads = 1;
+#if TLS_MULTIPLE_THREADS_IN_TCB || !defined USE_TLS || !TLS_DTV_AT_TP
+ __pthread_main_thread->p_multiple_threads = 1;
+#endif
+ *__libc_multiple_threads_ptr = 1;
+
+#ifndef HAVE_Z_NODELETE
+ if (__builtin_expect (&__dso_handle != NULL, 1))
+ __cxa_atexit ((void (*) (void *)) pthread_atexit_retcode, NULL,
+ __dso_handle);
+#endif
+
+ if (__pthread_max_stacksize == 0)
+ __pthread_init_max_stacksize ();
+ /* If basic initialization not done yet (e.g. we're called from a
+ constructor run before our constructor), do it now */
+ if (__pthread_initial_thread_bos == NULL) pthread_initialize();
+ /* Setup stack for thread manager */
+ __pthread_manager_thread_bos = malloc(THREAD_MANAGER_STACK_SIZE);
+ if (__pthread_manager_thread_bos == NULL) return -1;
+ __pthread_manager_thread_tos =
+ __pthread_manager_thread_bos + THREAD_MANAGER_STACK_SIZE;
+ /* Setup pipe to communicate with thread manager */
+ if (pipe(manager_pipe) == -1) {
+ free(__pthread_manager_thread_bos);
+ return -1;
+ }
+
+#ifdef USE_TLS
+ /* Allocate memory for the thread descriptor and the dtv. */
+ tcbp = _dl_allocate_tls (NULL);
+ if (tcbp == NULL) {
+ free(__pthread_manager_thread_bos);
+ close_not_cancel(manager_pipe[0]);
+ close_not_cancel(manager_pipe[1]);
+ return -1;
+ }
+
+# if TLS_TCB_AT_TP
+ mgr = (pthread_descr) tcbp;
+# elif TLS_DTV_AT_TP
+ /* pthread_descr is located right below tcbhead_t which _dl_allocate_tls
+ returns. */
+ mgr = (pthread_descr) ((char *) tcbp - TLS_PRE_TCB_SIZE);
+# endif
+ __pthread_handles[1].h_descr = manager_thread = mgr;
+
+ /* Initialize the descriptor. */
+#if !defined USE_TLS || !TLS_DTV_AT_TP
+ mgr->p_header.data.tcb = tcbp;
+ mgr->p_header.data.self = mgr;
+ mgr->p_header.data.multiple_threads = 1;
+#elif TLS_MULTIPLE_THREADS_IN_TCB
+ mgr->p_multiple_threads = 1;
+#endif
+ mgr->p_lock = &__pthread_handles[1].h_lock;
+# ifndef HAVE___THREAD
+ mgr->p_errnop = &mgr->p_errno;
+# endif
+ mgr->p_start_args = (struct pthread_start_args) PTHREAD_START_ARGS_INITIALIZER(__pthread_manager);
+ mgr->p_nr = 1;
+# if __LT_SPINLOCK_INIT != 0
+ self->p_resume_count = (struct pthread_atomic) __ATOMIC_INITIALIZER;
+# endif
+ mgr->p_alloca_cutoff = PTHREAD_STACK_MIN / 4;
+#else
+ mgr = &__pthread_manager_thread;
+#endif
+
+ __pthread_manager_request = manager_pipe[1]; /* writing end */
+ __pthread_manager_reader = manager_pipe[0]; /* reading end */
+
+ /* Start the thread manager */
+ pid = 0;
+#ifdef USE_TLS
+ if (__linuxthreads_initial_report_events != 0)
+ THREAD_SETMEM (((pthread_descr) NULL), p_report_events,
+ __linuxthreads_initial_report_events);
+ report_events = THREAD_GETMEM (((pthread_descr) NULL), p_report_events);
+#else
+ if (__linuxthreads_initial_report_events != 0)
+ __pthread_initial_thread.p_report_events
+ = __linuxthreads_initial_report_events;
+ report_events = __pthread_initial_thread.p_report_events;
+#endif
+ if (__builtin_expect (report_events, 0))
+ {
+ /* It's a bit more complicated. We have to report the creation of
+ the manager thread. */
+ int idx = __td_eventword (TD_CREATE);
+ uint32_t mask = __td_eventmask (TD_CREATE);
+ uint32_t event_bits;
+
+#ifdef USE_TLS
+ event_bits = THREAD_GETMEM_NC (((pthread_descr) NULL),
+ p_eventbuf.eventmask.event_bits[idx]);
+#else
+ event_bits = __pthread_initial_thread.p_eventbuf.eventmask.event_bits[idx];
+#endif
+
+ if ((mask & (__pthread_threads_events.event_bits[idx] | event_bits))
+ != 0)
+ {
+ __pthread_lock(mgr->p_lock, NULL);
+
+#ifdef NEED_SEPARATE_REGISTER_STACK
+ pid = __clone2(__pthread_manager_event,
+ (void **) __pthread_manager_thread_bos,
+ THREAD_MANAGER_STACK_SIZE,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND,
+ mgr);
+#elif _STACK_GROWS_UP
+ pid = __clone(__pthread_manager_event,
+ (void **) __pthread_manager_thread_bos,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND,
+ mgr);
+#else
+ pid = __clone(__pthread_manager_event,
+ (void **) __pthread_manager_thread_tos,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND,
+ mgr);
+#endif
+
+ if (pid != -1)
+ {
+ /* Now fill in the information about the new thread in
+ the newly created thread's data structure. We cannot let
+ the new thread do this since we don't know whether it was
+ already scheduled when we send the event. */
+ mgr->p_eventbuf.eventdata = mgr;
+ mgr->p_eventbuf.eventnum = TD_CREATE;
+ __pthread_last_event = mgr;
+ mgr->p_tid = 2* PTHREAD_THREADS_MAX + 1;
+ mgr->p_pid = pid;
+
+ /* Now call the function which signals the event. */
+ __linuxthreads_create_event ();
+ }
+
+ /* Now restart the thread. */
+ __pthread_unlock(mgr->p_lock);
+ }
+ }
+
+ if (__builtin_expect (pid, 0) == 0)
+ {
+#ifdef NEED_SEPARATE_REGISTER_STACK
+ pid = __clone2(__pthread_manager, (void **) __pthread_manager_thread_bos,
+ THREAD_MANAGER_STACK_SIZE,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, mgr);
+#elif _STACK_GROWS_UP
+ pid = __clone(__pthread_manager, (void **) __pthread_manager_thread_bos,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, mgr);
+#else
+ pid = __clone(__pthread_manager, (void **) __pthread_manager_thread_tos,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, mgr);
+#endif
+ }
+ if (__builtin_expect (pid, 0) == -1) {
+#ifdef USE_TLS
+ _dl_deallocate_tls (tcbp, true);
+#endif
+ free(__pthread_manager_thread_bos);
+ close_not_cancel(manager_pipe[0]);
+ close_not_cancel(manager_pipe[1]);
+ return -1;
+ }
+ mgr->p_tid = 2* PTHREAD_THREADS_MAX + 1;
+ mgr->p_pid = pid;
+ /* Make gdb aware of new thread manager */
+ if (__builtin_expect (__pthread_threads_debug, 0) && __pthread_sig_debug > 0)
+ {
+ raise(__pthread_sig_debug);
+ /* We suspend ourself and gdb will wake us up when it is
+ ready to handle us. */
+ __pthread_wait_for_restart_signal(thread_self());
+ }
+ /* Synchronize debugging of the thread manager */
+ request.req_kind = REQ_DEBUG;
+ TEMP_FAILURE_RETRY(write_not_cancel(__pthread_manager_request,
+ (char *) &request, sizeof(request)));
+ return 0;
+}
+
+/* Thread creation */
+
+int __pthread_create(pthread_t *thread, const pthread_attr_t *attr,
+ void * (*start_routine)(void *), void *arg)
+{
+ pthread_descr self = thread_self();
+ struct pthread_request request;
+ int retval;
+ if (__builtin_expect (__pthread_manager_request, 0) < 0) {
+ if (__pthread_initialize_manager() < 0) return EAGAIN;
+ }
+ request.req_thread = self;
+ request.req_kind = REQ_CREATE;
+ request.req_args.create.attr = attr;
+ request.req_args.create.fn = start_routine;
+ request.req_args.create.arg = arg;
+ sigprocmask(SIG_SETMASK, (const sigset_t *) NULL,
+ &request.req_args.create.mask);
+ TEMP_FAILURE_RETRY(write_not_cancel(__pthread_manager_request,
+ (char *) &request, sizeof(request)));
+ suspend(self);
+ retval = THREAD_GETMEM(self, p_retcode);
+ if (__builtin_expect (retval, 0) == 0)
+ *thread = (pthread_t) THREAD_GETMEM(self, p_retval);
+ return retval;
+}
+strong_alias (__pthread_create, pthread_create)
+
+/* Simple operations on thread identifiers */
+
+pthread_descr __pthread_thread_self(void)
+{
+ return thread_self();
+}
+
+pthread_t __pthread_self(void)
+{
+ pthread_descr self = thread_self();
+ return THREAD_GETMEM(self, p_tid);
+}
+strong_alias (__pthread_self, pthread_self);
+
+int __pthread_equal(pthread_t thread1, pthread_t thread2)
+{
+ return thread1 == thread2;
+}
+strong_alias (__pthread_equal, pthread_equal);
+
+/* Helper function for thread_self in the case of user-provided stacks */
+
+#ifndef THREAD_SELF
+
+pthread_descr __pthread_find_self(void)
+{
+ char * sp = CURRENT_STACK_FRAME;
+ pthread_handle h;
+
+ /* __pthread_handles[0] is the initial thread, __pthread_handles[1] is
+ the manager threads handled specially in thread_self(), so start at 2 */
+ h = __pthread_handles + 2;
+# ifdef _STACK_GROWS_UP
+ while (! (sp >= (char *) h->h_descr && sp < (char *) h->h_descr->p_guardaddr)) h++;
+# else
+ while (! (sp <= (char *) h->h_descr && sp >= h->h_bottom)) h++;
+# endif
+ return h->h_descr;
+}
+
+#else
+
+pthread_descr __pthread_self_stack(void)
+{
+ char *sp = CURRENT_STACK_FRAME;
+ pthread_handle h;
+
+ if (sp >= __pthread_manager_thread_bos && sp < __pthread_manager_thread_tos)
+ return manager_thread;
+ h = __pthread_handles + 2;
+# ifdef USE_TLS
+# ifdef _STACK_GROWS_UP
+ while (h->h_descr == NULL
+ || ! (sp >= h->h_descr->p_stackaddr && sp < h->h_descr->p_guardaddr))
+ h++;
+# else
+ while (h->h_descr == NULL
+ || ! (sp <= (char *) h->h_descr->p_stackaddr && sp >= h->h_bottom))
+ h++;
+# endif
+# else
+# ifdef _STACK_GROWS_UP
+ while (! (sp >= (char *) h->h_descr && sp < h->h_descr->p_guardaddr))
+ h++;
+# else
+ while (! (sp <= (char *) h->h_descr && sp >= h->h_bottom))
+ h++;
+# endif
+# endif
+ return h->h_descr;
+}
+
+#endif
+
+/* Thread scheduling */
+
+int __pthread_setschedparam(pthread_t thread, int policy,
+ const struct sched_param *param)
+{
+ pthread_handle handle = thread_handle(thread);
+ pthread_descr th;
+
+ __pthread_lock(&handle->h_lock, NULL);
+ if (__builtin_expect (invalid_handle(handle, thread), 0)) {
+ __pthread_unlock(&handle->h_lock);
+ return ESRCH;
+ }
+ th = handle->h_descr;
+ if (__builtin_expect (__sched_setscheduler(th->p_pid, policy, param) == -1,
+ 0)) {
+ __pthread_unlock(&handle->h_lock);
+ return errno;
+ }
+ th->p_priority = policy == SCHED_OTHER ? 0 : param->sched_priority;
+ __pthread_unlock(&handle->h_lock);
+ if (__pthread_manager_request >= 0)
+ __pthread_manager_adjust_prio(th->p_priority);
+ return 0;
+}
+strong_alias (__pthread_setschedparam, pthread_setschedparam);
+
+int __pthread_getschedparam(pthread_t thread, int *policy,
+ struct sched_param *param)
+{
+ pthread_handle handle = thread_handle(thread);
+ int pid, pol;
+
+ __pthread_lock(&handle->h_lock, NULL);
+ if (__builtin_expect (invalid_handle(handle, thread), 0)) {
+ __pthread_unlock(&handle->h_lock);
+ return ESRCH;
+ }
+ pid = handle->h_descr->p_pid;
+ __pthread_unlock(&handle->h_lock);
+ pol = __sched_getscheduler(pid);
+ if (__builtin_expect (pol, 0) == -1) return errno;
+ if (__sched_getparam(pid, param) == -1) return errno;
+ *policy = pol;
+ return 0;
+}
+strong_alias (__pthread_getschedparam, pthread_getschedparam);
+
+int __pthread_yield (void)
+{
+ /* For now this is equivalent with the POSIX call. */
+ return sched_yield ();
+}
+weak_alias (__pthread_yield, pthread_yield)
+
+/* Process-wide exit() request */
+
+static void pthread_onexit_process(int retcode, void *arg)
+{
+ if (__builtin_expect (__pthread_manager_request, 0) >= 0) {
+ struct pthread_request request;
+ pthread_descr self = thread_self();
+
+ request.req_thread = self;
+ request.req_kind = REQ_PROCESS_EXIT;
+ request.req_args.exit.code = retcode;
+ TEMP_FAILURE_RETRY(write_not_cancel(__pthread_manager_request,
+ (char *) &request, sizeof(request)));
+ suspend(self);
+ /* Main thread should accumulate times for thread manager and its
+ children, so that timings for main thread account for all threads. */
+ if (self == __pthread_main_thread)
+ {
+#ifdef USE_TLS
+ waitpid(manager_thread->p_pid, NULL, __WCLONE);
+#else
+ waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
+#endif
+ /* Since all threads have been asynchronously terminated
+ (possibly holding locks), free cannot be used any more.
+ For mtrace, we'd like to print something though. */
+ /* #ifdef USE_TLS
+ tcbhead_t *tcbp = (tcbhead_t *) manager_thread;
+ # if TLS_DTV_AT_TP
+ tcbp = (tcbhead_t) ((char *) tcbp + TLS_PRE_TCB_SIZE);
+ # endif
+ _dl_deallocate_tls (tcbp, true);
+ #endif
+ free (__pthread_manager_thread_bos); */
+ __pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL;
+ }
+ }
+}
+
+#ifndef HAVE_Z_NODELETE
+static int __pthread_atexit_retcode;
+
+static void pthread_atexit_process(void *arg, int retcode)
+{
+ pthread_onexit_process (retcode ?: __pthread_atexit_retcode, arg);
+}
+
+static void pthread_atexit_retcode(void *arg, int retcode)
+{
+ __pthread_atexit_retcode = retcode;
+}
+#endif
+
+/* The handler for the RESTART signal just records the signal received
+ in the thread descriptor, and optionally performs a siglongjmp
+ (for pthread_cond_timedwait). */
+
+static void pthread_handle_sigrestart(int sig)
+{
+ pthread_descr self = check_thread_self();
+ THREAD_SETMEM(self, p_signal, sig);
+ if (THREAD_GETMEM(self, p_signal_jmp) != NULL)
+ siglongjmp(*THREAD_GETMEM(self, p_signal_jmp), 1);
+}
+
+/* The handler for the CANCEL signal checks for cancellation
+ (in asynchronous mode), for process-wide exit and exec requests.
+ For the thread manager thread, redirect the signal to
+ __pthread_manager_sighandler. */
+
+static void pthread_handle_sigcancel(int sig)
+{
+ pthread_descr self = check_thread_self();
+ sigjmp_buf * jmpbuf;
+
+ if (self == manager_thread)
+ {
+ __pthread_manager_sighandler(sig);
+ return;
+ }
+ if (__builtin_expect (__pthread_exit_requested, 0)) {
+ /* Main thread should accumulate times for thread manager and its
+ children, so that timings for main thread account for all threads. */
+ if (self == __pthread_main_thread) {
+#ifdef USE_TLS
+ waitpid(manager_thread->p_pid, NULL, __WCLONE);
+#else
+ waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE);
+#endif
+ }
+ _exit(__pthread_exit_code);
+ }
+ if (__builtin_expect (THREAD_GETMEM(self, p_canceled), 0)
+ && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
+ if (THREAD_GETMEM(self, p_canceltype) == PTHREAD_CANCEL_ASYNCHRONOUS)
+ __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
+ jmpbuf = THREAD_GETMEM(self, p_cancel_jmp);
+ if (jmpbuf != NULL) {
+ THREAD_SETMEM(self, p_cancel_jmp, NULL);
+ siglongjmp(*jmpbuf, 1);
+ }
+ }
+}
+
+/* Handler for the DEBUG signal.
+ The debugging strategy is as follows:
+ On reception of a REQ_DEBUG request (sent by new threads created to
+ the thread manager under debugging mode), the thread manager throws
+ __pthread_sig_debug to itself. The debugger (if active) intercepts
+ this signal, takes into account new threads and continue execution
+ of the thread manager by propagating the signal because it doesn't
+ know what it is specifically done for. In the current implementation,
+ the thread manager simply discards it. */
+
+static void pthread_handle_sigdebug(int sig)
+{
+ /* Nothing */
+}
+
+/* Reset the state of the thread machinery after a fork().
+ Close the pipe used for requests and set the main thread to the forked
+ thread.
+ Notice that we can't free the stack segments, as the forked thread
+ may hold pointers into them. */
+
+void __pthread_reset_main_thread(void)
+{
+ pthread_descr self = thread_self();
+
+ if (__pthread_manager_request != -1) {
+ /* Free the thread manager stack */
+ free(__pthread_manager_thread_bos);
+ __pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL;
+ /* Close the two ends of the pipe */
+ close_not_cancel(__pthread_manager_request);
+ close_not_cancel(__pthread_manager_reader);
+ __pthread_manager_request = __pthread_manager_reader = -1;
+ }
+
+ /* Update the pid of the main thread */
+ THREAD_SETMEM(self, p_pid, __getpid());
+ /* Make the forked thread the main thread */
+ __pthread_main_thread = self;
+ THREAD_SETMEM(self, p_nextlive, self);
+ THREAD_SETMEM(self, p_prevlive, self);
+#if !(USE_TLS && HAVE___THREAD)
+ /* Now this thread modifies the global variables. */
+ THREAD_SETMEM(self, p_errnop, &_errno);
+ THREAD_SETMEM(self, p_h_errnop, &_h_errno);
+ THREAD_SETMEM(self, p_resp, &_res);
+#endif
+
+#ifndef FLOATING_STACKS
+ /* This is to undo the setrlimit call in __pthread_init_max_stacksize.
+ XXX This can be wrong if the user set the limit during the run. */
+ {
+ struct rlimit limit;
+ if (getrlimit (RLIMIT_STACK, &limit) == 0
+ && limit.rlim_cur != limit.rlim_max)
+ {
+ limit.rlim_cur = limit.rlim_max;
+ setrlimit(RLIMIT_STACK, &limit);
+ }
+ }
+#endif
+}
+
+/* Process-wide exec() request */
+
+void __pthread_kill_other_threads_np(void)
+{
+ struct sigaction sa;
+ /* Terminate all other threads and thread manager */
+ pthread_onexit_process(0, NULL);
+ /* Make current thread the main thread in case the calling thread
+ changes its mind, does not exec(), and creates new threads instead. */
+ __pthread_reset_main_thread();
+
+ /* Reset the signal handlers behaviour for the signals the
+ implementation uses since this would be passed to the new
+ process. */
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+ sa.sa_handler = SIG_DFL;
+ __libc_sigaction(__pthread_sig_restart, &sa, NULL);
+ __libc_sigaction(__pthread_sig_cancel, &sa, NULL);
+ if (__pthread_sig_debug > 0)
+ __libc_sigaction(__pthread_sig_debug, &sa, NULL);
+}
+weak_alias (__pthread_kill_other_threads_np, pthread_kill_other_threads_np)
+
+/* Concurrency symbol level. */
+static int current_level;
+
+int __pthread_setconcurrency(int level)
+{
+ /* We don't do anything unless we have found a useful interpretation. */
+ current_level = level;
+ return 0;
+}
+weak_alias (__pthread_setconcurrency, pthread_setconcurrency)
+
+int __pthread_getconcurrency(void)
+{
+ return current_level;
+}
+weak_alias (__pthread_getconcurrency, pthread_getconcurrency)
+
+/* Primitives for controlling thread execution */
+
+void __pthread_wait_for_restart_signal(pthread_descr self)
+{
+ sigset_t mask;
+
+ sigprocmask(SIG_SETMASK, NULL, &mask); /* Get current signal mask */
+ sigdelset(&mask, __pthread_sig_restart); /* Unblock the restart signal */
+ THREAD_SETMEM(self, p_signal, 0);
+ do {
+ __pthread_sigsuspend(&mask); /* Wait for signal. Must not be a
+ cancellation point. */
+ } while (THREAD_GETMEM(self, p_signal) !=__pthread_sig_restart);
+
+ READ_MEMORY_BARRIER(); /* See comment in __pthread_restart_new */
+}
+
+#if !__ASSUME_REALTIME_SIGNALS
+/* The _old variants are for 2.0 and early 2.1 kernels which don't have RT
+ signals.
+ On these kernels, we use SIGUSR1 and SIGUSR2 for restart and cancellation.
+ Since the restart signal does not queue, we use an atomic counter to create
+ queuing semantics. This is needed to resolve a rare race condition in
+ pthread_cond_timedwait_relative. */
+
+void __pthread_restart_old(pthread_descr th)
+{
+ if (atomic_increment(&th->p_resume_count) == -1)
+ kill(th->p_pid, __pthread_sig_restart);
+}
+
+void __pthread_suspend_old(pthread_descr self)
+{
+ if (atomic_decrement(&self->p_resume_count) <= 0)
+ __pthread_wait_for_restart_signal(self);
+}
+
+int
+__pthread_timedsuspend_old(pthread_descr self, const struct timespec *abstime)
+{
+ sigset_t unblock, initial_mask;
+ int was_signalled = 0;
+ sigjmp_buf jmpbuf;
+
+ if (atomic_decrement(&self->p_resume_count) == 0) {
+ /* Set up a longjmp handler for the restart signal, unblock
+ the signal and sleep. */
+
+ if (sigsetjmp(jmpbuf, 1) == 0) {
+ THREAD_SETMEM(self, p_signal_jmp, &jmpbuf);
+ THREAD_SETMEM(self, p_signal, 0);
+ /* Unblock the restart signal */
+ sigemptyset(&unblock);
+ sigaddset(&unblock, __pthread_sig_restart);
+ sigprocmask(SIG_UNBLOCK, &unblock, &initial_mask);
+
+ while (1) {
+ struct timeval now;
+ struct timespec reltime;
+
+ /* Compute a time offset relative to now. */
+ __gettimeofday (&now, NULL);
+ reltime.tv_nsec = abstime->tv_nsec - now.tv_usec * 1000;
+ reltime.tv_sec = abstime->tv_sec - now.tv_sec;
+ if (reltime.tv_nsec < 0) {
+ reltime.tv_nsec += 1000000000;
+ reltime.tv_sec -= 1;
+ }
+
+ /* Sleep for the required duration. If woken by a signal,
+ resume waiting as required by Single Unix Specification. */
+ if (reltime.tv_sec < 0 || __libc_nanosleep(&reltime, NULL) == 0)
+ break;
+ }
+
+ /* Block the restart signal again */
+ sigprocmask(SIG_SETMASK, &initial_mask, NULL);
+ was_signalled = 0;
+ } else {
+ was_signalled = 1;
+ }
+ THREAD_SETMEM(self, p_signal_jmp, NULL);
+ }
+
+ /* Now was_signalled is true if we exited the above code
+ due to the delivery of a restart signal. In that case,
+ we know we have been dequeued and resumed and that the
+ resume count is balanced. Otherwise, there are some
+ cases to consider. First, try to bump up the resume count
+ back to zero. If it goes to 1, it means restart() was
+ invoked on this thread. The signal must be consumed
+ and the count bumped down and everything is cool. We
+ can return a 1 to the caller.
+ Otherwise, no restart was delivered yet, so a potential
+ race exists; we return a 0 to the caller which must deal
+ with this race in an appropriate way; for example by
+ atomically removing the thread from consideration for a
+ wakeup---if such a thing fails, it means a restart is
+ being delivered. */
+
+ if (!was_signalled) {
+ if (atomic_increment(&self->p_resume_count) != -1) {
+ __pthread_wait_for_restart_signal(self);
+ atomic_decrement(&self->p_resume_count); /* should be zero now! */
+ /* woke spontaneously and consumed restart signal */
+ return 1;
+ }
+ /* woke spontaneously but did not consume restart---caller must resolve */
+ return 0;
+ }
+ /* woken due to restart signal */
+ return 1;
+}
+#endif /* __ASSUME_REALTIME_SIGNALS */
+
+void __pthread_restart_new(pthread_descr th)
+{
+ /* The barrier is proabably not needed, in which case it still documents
+ our assumptions. The intent is to commit previous writes to shared
+ memory so the woken thread will have a consistent view. Complementary
+ read barriers are present to the suspend functions. */
+ WRITE_MEMORY_BARRIER();
+ kill(th->p_pid, __pthread_sig_restart);
+}
+
+/* There is no __pthread_suspend_new because it would just
+ be a wasteful wrapper for __pthread_wait_for_restart_signal */
+
+int
+__pthread_timedsuspend_new(pthread_descr self, const struct timespec *abstime)
+{
+ sigset_t unblock, initial_mask;
+ int was_signalled = 0;
+ sigjmp_buf jmpbuf;
+
+ if (sigsetjmp(jmpbuf, 1) == 0) {
+ THREAD_SETMEM(self, p_signal_jmp, &jmpbuf);
+ THREAD_SETMEM(self, p_signal, 0);
+ /* Unblock the restart signal */
+ sigemptyset(&unblock);
+ sigaddset(&unblock, __pthread_sig_restart);
+ sigprocmask(SIG_UNBLOCK, &unblock, &initial_mask);
+
+ while (1) {
+ struct timeval now;
+ struct timespec reltime;
+
+ /* Compute a time offset relative to now. */
+ __gettimeofday (&now, NULL);
+ reltime.tv_nsec = abstime->tv_nsec - now.tv_usec * 1000;
+ reltime.tv_sec = abstime->tv_sec - now.tv_sec;
+ if (reltime.tv_nsec < 0) {
+ reltime.tv_nsec += 1000000000;
+ reltime.tv_sec -= 1;
+ }
+
+ /* Sleep for the required duration. If woken by a signal,
+ resume waiting as required by Single Unix Specification. */
+ if (reltime.tv_sec < 0 || __libc_nanosleep(&reltime, NULL) == 0)
+ break;
+ }
+
+ /* Block the restart signal again */
+ sigprocmask(SIG_SETMASK, &initial_mask, NULL);
+ was_signalled = 0;
+ } else {
+ was_signalled = 1;
+ }
+ THREAD_SETMEM(self, p_signal_jmp, NULL);
+
+ /* Now was_signalled is true if we exited the above code
+ due to the delivery of a restart signal. In that case,
+ everything is cool. We have been removed from whatever
+ we were waiting on by the other thread, and consumed its signal.
+
+ Otherwise we this thread woke up spontaneously, or due to a signal other
+ than restart. This is an ambiguous case that must be resolved by
+ the caller; the thread is still eligible for a restart wakeup
+ so there is a race. */
+
+ READ_MEMORY_BARRIER(); /* See comment in __pthread_restart_new */
+ return was_signalled;
+}
+
+
+/* Debugging aid */
+
+#ifdef DEBUG
+#include <stdarg.h>
+
+void __pthread_message(const char * fmt, ...)
+{
+ char buffer[1024];
+ va_list args;
+ sprintf(buffer, "%05d : ", __getpid());
+ va_start(args, fmt);
+ vsnprintf(buffer + 8, sizeof(buffer) - 8, fmt, args);
+ va_end(args);
+ TEMP_FAILURE_RETRY(write_not_cancel(2, buffer, strlen(buffer)));
+}
+
+#endif