Merge in the pthread library. This is the linuxthreads library taken from

glibc 2.1.3 and ported to work with uClibc by Stefan Soucek and Erik Andersen
(me).  Stefan has hacked things up such that linuxthreads runs on MMU-less
systems (tested only on arm-nommu).  Erik cleaned things up and made it work
properly as a shared library.
 -Erik

1 files changed, 209 insertions, 0 deletions

diff --git a/libpthread/linuxthreads/semaphore.c b/libpthread/linuxthreads/semaphore.c
new file mode 100644
index 000000000..0297b3a1e
--- /dev/null
+++ b/libpthread/linuxthreads/semaphore.c
@@ -0,0 +1,209 @@
+/* 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.                 */
+
+/* Semaphores a la POSIX 1003.1b */
+
+#include <errno.h>
+#include "pthread.h"
+#include "semaphore.h"
+#include "internals.h"
+#include "spinlock.h"
+#include "restart.h"
+#include "queue.h"
+
+int __new_sem_init(sem_t *sem, int pshared, unsigned int value)
+{
+  if (value > SEM_VALUE_MAX) {
+    errno = EINVAL;
+    return -1;
+  }
+  if (pshared) {
+    errno = ENOSYS;
+    return -1;
+  }
+  __pthread_init_lock((struct _pthread_fastlock *) &sem->__sem_lock);
+  sem->__sem_value = value;
+  sem->__sem_waiting = NULL;
+  return 0;
+}
+
+/* Function called by pthread_cancel to remove the thread from
+   waiting inside __new_sem_wait. */
+
+static int new_sem_extricate_func(void *obj, pthread_descr th)
+{
+  volatile pthread_descr self = thread_self();
+  sem_t *sem = obj;
+  int did_remove = 0;
+
+  __pthread_lock((struct _pthread_fastlock *) &sem->__sem_lock, self);
+  did_remove = remove_from_queue(&sem->__sem_waiting, th);
+  __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+
+  return did_remove;
+}
+
+int __new_sem_wait(sem_t * sem)
+{
+  volatile pthread_descr self = thread_self();
+  pthread_extricate_if extr;
+  int already_canceled = 0;
+
+  /* Set up extrication interface */
+  extr.pu_object = sem;
+  extr.pu_extricate_func = new_sem_extricate_func;
+
+  __pthread_lock((struct _pthread_fastlock *) &sem->__sem_lock, self);
+  if (sem->__sem_value > 0) {
+    sem->__sem_value--;
+    __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+    return 0;
+  }
+  /* Register extrication interface */
+  __pthread_set_own_extricate_if(self, &extr); 
+  /* Enqueue only if not already cancelled. */
+  if (!(THREAD_GETMEM(self, p_canceled)
+      && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE))
+    enqueue(&sem->__sem_waiting, self);
+  else
+    already_canceled = 1;
+  __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+
+  if (already_canceled) {
+    __pthread_set_own_extricate_if(self, 0); 
+    pthread_exit(PTHREAD_CANCELED);
+  } 
+
+  /* Wait for sem_post or cancellation, or fall through if already canceled */
+  suspend(self);
+  __pthread_set_own_extricate_if(self, 0); 
+
+  /* Terminate only if the wakeup came from cancellation. */
+  /* Otherwise ignore cancellation because we got the semaphore. */
+
+  if (THREAD_GETMEM(self, p_woken_by_cancel)
+      && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) {
+    THREAD_SETMEM(self, p_woken_by_cancel, 0);
+    pthread_exit(PTHREAD_CANCELED);
+  }
+  /* We got the semaphore */
+  return 0;
+}
+
+int __new_sem_trywait(sem_t * sem)
+{
+  int retval;
+
+  __pthread_lock((struct _pthread_fastlock *) &sem->__sem_lock, NULL);
+  if (sem->__sem_value == 0) {
+    errno = EAGAIN;
+    retval = -1;
+  } else {
+    sem->__sem_value--;
+    retval = 0;
+  }
+  __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+  return retval;
+}
+
+int __new_sem_post(sem_t * sem)
+{
+  pthread_descr self = thread_self();
+  pthread_descr th;
+  struct pthread_request request;
+
+  if (THREAD_GETMEM(self, p_in_sighandler) == NULL) {
+    __pthread_lock((struct _pthread_fastlock *) &sem->__sem_lock, self);
+    if (sem->__sem_waiting == NULL) {
+      if (sem->__sem_value >= SEM_VALUE_MAX) {
+        /* Overflow */
+        errno = ERANGE;
+        __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+        return -1;
+      }
+      sem->__sem_value++;
+      __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+    } else {
+      th = dequeue(&sem->__sem_waiting);
+      __pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+      restart(th);
+    }
+  } else {
+    /* If we're in signal handler, delegate post operation to
+       the thread manager. */
+    if (__pthread_manager_request < 0) {
+      if (__pthread_initialize_manager() < 0) {
+        errno = EAGAIN;
+        return -1;
+      }
+    }
+    request.req_kind = REQ_POST;
+    request.req_args.post = sem;
+    __libc_write(__pthread_manager_request,
+                 (char *) &request, sizeof(request));
+  }
+  return 0;
+}
+
+int __new_sem_getvalue(sem_t * sem, int * sval)
+{
+  *sval = sem->__sem_value;
+  return 0;
+}
+
+int __new_sem_destroy(sem_t * sem)
+{
+  if (sem->__sem_waiting != NULL) {
+    __set_errno (EBUSY);
+    return -1;
+  }
+  return 0;
+}
+
+sem_t *sem_open(const char *name, int oflag, ...)
+{
+  __set_errno (ENOSYS);
+  return SEM_FAILED;
+}
+
+int sem_close(sem_t *sem)
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+int sem_unlink(const char *name)
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+#if defined PIC && DO_VERSIONING
+default_symbol_version (__new_sem_init, sem_init, GLIBC_2.1);
+default_symbol_version (__new_sem_wait, sem_wait, GLIBC_2.1);
+default_symbol_version (__new_sem_trywait, sem_trywait, GLIBC_2.1);
+default_symbol_version (__new_sem_post, sem_post, GLIBC_2.1);
+default_symbol_version (__new_sem_getvalue, sem_getvalue, GLIBC_2.1);
+default_symbol_version (__new_sem_destroy, sem_destroy, GLIBC_2.1);
+#else
+# ifdef weak_alias
+weak_alias (__new_sem_init, sem_init)
+weak_alias (__new_sem_wait, sem_wait)
+weak_alias (__new_sem_trywait, sem_trywait)
+weak_alias (__new_sem_post, sem_post)
+weak_alias (__new_sem_getvalue, sem_getvalue)
+weak_alias (__new_sem_destroy, sem_destroy)
+# endif
+#endif
+