+/*
+ * mutexes.c: Mutex handles
+ *
+ * Author:
+ * Dick Porter (dick@ximian.com)
+ *
+ * (C) 2002 Ximian, Inc.
+ */
+
#include <config.h>
#include <glib.h>
#include <pthread.h>
#include <string.h>
+#include <unistd.h>
-#include "mono/io-layer/wapi.h"
-#include "wapi-private.h"
-#include "wait-private.h"
-#include "misc-private.h"
-#include "handles-private.h"
+#include <mono/io-layer/wapi.h>
+#include <mono/io-layer/wapi-private.h>
+#include <mono/io-layer/misc-private.h>
+#include <mono/io-layer/handles-private.h>
+#include <mono/io-layer/mono-mutex.h>
+#include <mono/io-layer/mutex-private.h>
-#define DEBUG
+#undef DEBUG
-struct _WapiHandle_mutex
-{
- WapiHandle handle;
- pthread_mutex_t mutex;
- pthread_t tid;
- guint32 recursion;
+/* This is used to serialise mutex creation when names are given
+ */
+static mono_mutex_t named_mutex_mutex;
+
+static void mutex_close_shared (gpointer handle);
+static void mutex_signal(gpointer handle);
+static void mutex_own (gpointer handle);
+static gboolean mutex_is_owned (gpointer handle);
+
+struct _WapiHandleOps _wapi_mutex_ops = {
+ mutex_close_shared, /* close_shared */
+ NULL, /* close_private */
+ mutex_signal, /* signal */
+ mutex_own, /* own */
+ mutex_is_owned, /* is_owned */
};
-static void mutex_close(WapiHandle *handle);
-static gboolean mutex_wait(WapiHandle *handle, guint32 ms);
-static guint32 mutex_wait_multiple(gpointer data);
-
-static struct _WapiHandleOps mutex_ops = {
- mutex_close, /* close */
- NULL, /* getfiletype */
- NULL, /* readfile */
- NULL, /* writefile */
- NULL, /* seek */
- NULL, /* setendoffile */
- NULL, /* getfilesize */
- mutex_wait, /* wait */
- mutex_wait_multiple, /* wait_multiple */
-};
+static mono_once_t mutex_ops_once=MONO_ONCE_INIT;
-static void mutex_close(WapiHandle *handle)
+static void mutex_ops_init (void)
{
- struct _WapiHandle_mutex *mutex_handle=(struct _WapiHandle_mutex *)handle;
-
-#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": closing mutex handle %p",
- mutex_handle);
-#endif
-}
+ int thr_ret;
+#if defined(_POSIX_THREAD_PROCESS_SHARED) && _POSIX_THREAD_PROCESS_SHARED != -1
+ pthread_mutexattr_t mutex_shared_attr;
-static gboolean mutex_wait(WapiHandle *handle, guint32 ms)
-{
- struct _WapiHandle_mutex *mutex_handle=(struct _WapiHandle_mutex *)handle;
- pthread_t tid=pthread_self();
- int ret;
-
-#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": waiting for mutex handle %p",
- mutex_handle);
-#endif
+ thr_ret = mono_mutexattr_init (&mutex_shared_attr);
+ g_assert (thr_ret == 0);
- if(mutex_handle->tid==tid) {
- /* We already own this mutex, so just increase the count and
- * return TRUE
- */
+ thr_ret = mono_mutexattr_setpshared (&mutex_shared_attr,
+ PTHREAD_PROCESS_SHARED);
+ g_assert (thr_ret == 0);
- mutex_handle->recursion++;
-
-#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Already own mutex handle %p (recursion %d)",
- mutex_handle, mutex_handle->recursion);
+ thr_ret = mono_mutex_init (&named_mutex_mutex, &mutex_shared_attr);
+ g_assert (thr_ret == 0);
+#else
+ thr_ret = mono_mutex_init (&named_mutex_mutex, NULL);
#endif
- return(TRUE);
- }
+ _wapi_handle_register_capabilities (WAPI_HANDLE_MUTEX,
+ WAPI_HANDLE_CAP_WAIT |
+ WAPI_HANDLE_CAP_SIGNAL |
+ WAPI_HANDLE_CAP_OWN);
+}
+
+static void mutex_close_shared (gpointer handle)
+{
+ struct _WapiHandle_mutex *mutex_handle;
+ gboolean ok;
- if(ms==INFINITE) {
- ret=pthread_mutex_lock(&mutex_handle->mutex);
- } else {
- struct timespec timeout;
-
- _wapi_calc_timeout(&timeout, ms);
-
- ret=pthread_mutex_timedlock(&mutex_handle->mutex, &timeout);
+ ok=_wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if(ok==FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ return;
}
-
- if(ret==0) {
- /* Mutex locked */
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": Locking mutex handle %p",
- mutex_handle);
+ g_message(G_GNUC_PRETTY_FUNCTION ": closing mutex handle %p", handle);
#endif
- mutex_handle->tid=tid;
- mutex_handle->recursion=1;
-
- return(TRUE);
- } else {
- /* ret might be ETIMEDOUT for timeout, or other for error */
-
-#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Failed to lock mutex handle %p: %s", mutex_handle,
- strerror(ret));
-#endif
- return(FALSE);
+ if(mutex_handle->sharedns.name!=0) {
+ _wapi_handle_scratch_delete (mutex_handle->sharedns.name);
+ mutex_handle->sharedns.name=0;
}
}
-static guint32 mutex_wait_multiple(gpointer data G_GNUC_UNUSED)
+static void mutex_signal(gpointer handle)
{
- WaitQueueItem *item=(WaitQueueItem *)data;
- GPtrArray *needed;
- int ret;
- guint32 numhandles;
- struct timespec timeout;
- pthread_t tid=pthread_self();
- guint32 i, iterations;
+ ReleaseMutex(handle);
+}
+
+static void mutex_own (gpointer handle)
+{
+ struct _WapiHandle_mutex *mutex_handle;
+ gboolean ok;
- numhandles=item->handles[WAPI_HANDLE_MUTEX]->len;
+ ok=_wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if(ok==FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ return;
+ }
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": waiting on %d mutex handles for %d ms", numhandles,
- item->timeout);
+ g_message(G_GNUC_PRETTY_FUNCTION ": owning mutex handle %p", handle);
#endif
- /*
- * See which ones we need to lock
- */
- needed=g_ptr_array_new();
- for(i=0; i<numhandles; i++) {
- struct _WapiHandle_mutex *mutex_handle;
-
- mutex_handle=g_ptr_array_index(
- item->handles[WAPI_HANDLE_MUTEX], i);
-
- if(mutex_handle->tid!=tid) {
- /* We don't have this one, so add it to the list */
- g_ptr_array_add(needed, mutex_handle);
- }
- }
+ _wapi_handle_set_signal_state (handle, FALSE, FALSE);
+
+ mutex_handle->pid=getpid ();
+ mutex_handle->tid=pthread_self ();
+ mutex_handle->recursion++;
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": need to lock %d mutex handles",
- needed->len);
+ g_message (G_GNUC_PRETTY_FUNCTION
+ ": mutex handle %p locked %d times by %d:%ld", handle,
+ mutex_handle->recursion, mutex_handle->pid,
+ mutex_handle->tid);
#endif
+}
+
+static gboolean mutex_is_owned (gpointer handle)
+{
+ struct _WapiHandle_mutex *mutex_handle;
+ gboolean ok;
- iterations=0;
- do {
- iterations++;
-
- /* If the timeout isnt INFINITE but greater than 1s,
- * split the timeout into 1s chunks
- */
- if((item->timeout!=INFINITE) &&
- (item->timeout < (iterations*1000))) {
- _wapi_calc_timeout(
- &timeout, item->timeout-((iterations-1)*1000));
- } else {
- _wapi_calc_timeout(&timeout, 1000);
- }
+ ok=_wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if(ok==FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ return(FALSE);
+ }
- /* Try and lock as many mutexes as we can until we run
- * out of time, but to avoid deadlocks back off if we
- * fail to lock one
- */
- for(i=0; i<needed->len; i++) {
- struct _WapiHandle_mutex *mutex_handle;
-
- mutex_handle=g_ptr_array_index(needed, i);
-
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Locking %d mutex %p (owner %ld, me %ld)",
- i, mutex_handle, mutex_handle->tid, tid);
-#endif
-
- ret=pthread_mutex_timedlock(&mutex_handle->mutex,
- &timeout);
-
-#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": timedlock ret %s",
- strerror(ret));
+ g_message(G_GNUC_PRETTY_FUNCTION
+ ": testing ownership mutex handle %p", handle);
#endif
- if(ret!=0) {
- /* ETIMEDOUT is the most likely, but
- * fail on other error too
- */
-
+ if(mutex_handle->recursion>0 &&
+ mutex_handle->pid==getpid () &&
+ mutex_handle->tid==pthread_self ()) {
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Lock %d mutex failed: %s", i,
- strerror(ret));
+ g_message (G_GNUC_PRETTY_FUNCTION
+ ": mutex handle %p owned by %d:%ld", handle,
+ getpid (), pthread_self ());
#endif
- while(i--) {
+ return(TRUE);
+ } else {
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Releasing %d mutex", i);
+ g_message (G_GNUC_PRETTY_FUNCTION
+ ": mutex handle %p not owned by %d:%ld, but locked %d times by %d:%ld", handle, getpid (), pthread_self (), mutex_handle->recursion, mutex_handle->pid, mutex_handle->tid);
#endif
- mutex_handle=g_ptr_array_index(needed,
- i);
- pthread_mutex_unlock(
- &mutex_handle->mutex);
- }
- break;
- }
+ return(FALSE);
+ }
+}
- /* OK, got that one. Don't record it as ours
- * though until we get them all
- */
- }
+struct mutex_check_data
+{
+ pid_t pid;
+ pthread_t tid;
+};
- if(i==needed->len) {
- /* We've locked all the mutexes. Update the
- * ones we already had, and record that the
- * new ones belong to us
- */
- for(i=0; i<numhandles; i++) {
- struct _WapiHandle_mutex *mutex_handle;
- guint32 idx;
+static gboolean mutex_check (gpointer handle, gpointer user_data)
+{
+ struct _WapiHandle_mutex *mutex_handle;
+ gboolean ok;
+ struct mutex_check_data *data = (struct mutex_check_data *)user_data;
+ int thr_ret;
+
+ ok = _wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if (ok == FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ return(FALSE);
+ }
- mutex_handle=g_ptr_array_index(
- item->handles[WAPI_HANDLE_MUTEX], i);
-
- idx=g_array_index(
- item->waitindex[WAPI_HANDLE_MUTEX],
- guint32, i);
- _wapi_handle_set_lowest(item, idx);
-
+ pthread_cleanup_push ((void(*)(void *))_wapi_handle_unlock_handle,
+ handle);
+ thr_ret = _wapi_handle_lock_handle (handle);
+ g_assert (thr_ret == 0);
+
+ if (mutex_handle->pid == data->pid &&
+ mutex_handle->tid == data->tid) {
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION
- ": Updating mutex %p", mutex_handle);
+ g_message (G_GNUC_PRETTY_FUNCTION
+ ": Mutex handle %p abandoned!", handle);
#endif
-
- if(mutex_handle->tid==tid) {
- /* We already own this mutex,
- * so just increase the count
- */
- mutex_handle->recursion++;
- } else {
- mutex_handle->tid=tid;
- mutex_handle->recursion=1;
- }
- }
+
+ mutex_handle->recursion = 0;
+ mutex_handle->pid = 0;
+ mutex_handle->tid = 0;
- g_ptr_array_free(needed, FALSE);
+ _wapi_handle_set_signal_state (handle, TRUE, FALSE);
+ }
- item->waited[WAPI_HANDLE_MUTEX]=TRUE;
- item->waitcount[WAPI_HANDLE_MUTEX]=numhandles;
-
- return(numhandles);
- }
- } while((item->timeout==INFINITE) ||
- (item->timeout > (iterations * 1000)));
+ thr_ret = _wapi_handle_unlock_handle (handle);
+ g_assert (thr_ret == 0);
+ pthread_cleanup_pop (0);
+
+ /* Return false to keep searching */
+ return(FALSE);
+}
- /* Didn't get all the locks, and timeout isn't INFINITE */
-
- g_ptr_array_free(needed, FALSE);
+/* When a thread exits, any mutexes it still holds need to be signalled */
+void _wapi_mutex_check_abandoned (pid_t pid, pthread_t tid)
+{
+ struct mutex_check_data data;
- item->waited[WAPI_HANDLE_MUTEX]=TRUE;
- item->waitcount[WAPI_HANDLE_MUTEX]=0;
+ data.pid = pid;
+ data.tid = tid;
- return(0);
+ _wapi_search_handle (WAPI_HANDLE_MUTEX, mutex_check, &data, NULL,
+ NULL);
}
/**
* @owned: If %TRUE, the mutex is created with the calling thread
* already owning the mutex.
* @name:Pointer to a string specifying the name of this mutex, or
- * %NULL. Currently ignored.
+ * %NULL.
*
* Creates a new mutex handle. A mutex is signalled when no thread
* owns it. A thread acquires ownership of the mutex by waiting for
*
* Return value: A new handle, or %NULL on error.
*/
-WapiHandle *CreateMutex(WapiSecurityAttributes *security G_GNUC_UNUSED, gboolean owned G_GNUC_UNUSED,
- const guchar *name G_GNUC_UNUSED)
+gpointer CreateMutex(WapiSecurityAttributes *security G_GNUC_UNUSED, gboolean owned,
+ const gunichar2 *name)
{
struct _WapiHandle_mutex *mutex_handle;
- WapiHandle *handle;
+ gpointer handle;
+ gboolean ok;
+ gchar *utf8_name;
+ int thr_ret;
+ gpointer ret = NULL;
- mutex_handle=(struct _WapiHandle_mutex *)g_new0(struct _WapiHandle_mutex, 1);
- handle=(WapiHandle *)mutex_handle;
- _WAPI_HANDLE_INIT(handle, WAPI_HANDLE_MUTEX, mutex_ops);
+ mono_once (&mutex_ops_once, mutex_ops_init);
- pthread_mutex_init(&mutex_handle->mutex, NULL);
- if(owned==TRUE) {
- pthread_t tid=pthread_self();
-
- pthread_mutex_lock(&mutex_handle->mutex);
+ /* w32 seems to guarantee that opening named mutexes can't
+ * race each other
+ */
+ pthread_cleanup_push ((void(*)(void *))mono_mutex_unlock_in_cleanup,
+ (void *)&named_mutex_mutex);
+ thr_ret = mono_mutex_lock (&named_mutex_mutex);
+ g_assert (thr_ret == 0);
+
+ /* Need to blow away any old errors here, because code tests
+ * for ERROR_ALREADY_EXISTS on success (!) to see if a mutex
+ * was freshly created
+ */
+ SetLastError (ERROR_SUCCESS);
+
+ if(name!=NULL) {
+ utf8_name=g_utf16_to_utf8 (name, -1, NULL, NULL, NULL);
+ } else {
+ utf8_name=NULL;
+ }
+
+#ifdef DEBUG
+ g_message (G_GNUC_PRETTY_FUNCTION ": Creating mutex (name [%s])",
+ utf8_name==NULL?"<unnamed>":utf8_name);
+#endif
+
+ if(name!=NULL) {
+ handle=_wapi_search_handle_namespace (
+ WAPI_HANDLE_MUTEX, utf8_name,
+ (gpointer *)&mutex_handle, NULL);
+ if(handle==_WAPI_HANDLE_INVALID) {
+ /* The name has already been used for a different
+ * object.
+ */
+ g_free (utf8_name);
+ SetLastError (ERROR_INVALID_HANDLE);
+ goto cleanup;
+ } else if (handle!=NULL) {
+ g_free (utf8_name);
+ _wapi_handle_ref (handle);
+ ret = handle;
+
+ /* Not an error, but this is how the caller is
+ * informed that the mutex wasn't freshly
+ * created
+ */
+ SetLastError (ERROR_ALREADY_EXISTS);
+ goto cleanup;
+ }
+ /* Otherwise fall through to create the mutex. */
+ }
+
+ handle=_wapi_handle_new (WAPI_HANDLE_MUTEX);
+ if(handle==_WAPI_HANDLE_INVALID) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error creating mutex handle");
+ if(utf8_name!=NULL) {
+ g_free (utf8_name);
+ }
+ goto cleanup;
+ }
+
+ pthread_cleanup_push ((void(*)(void *))_wapi_handle_unlock_handle,
+ handle);
+ thr_ret = _wapi_handle_lock_handle (handle);
+ g_assert (thr_ret == 0);
+
+ ok=_wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if(ok==FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ if(utf8_name!=NULL) {
+ g_free (utf8_name);
+ }
- mutex_handle->tid=tid;
- mutex_handle->recursion=1;
+ goto handle_cleanup;
+ }
+ ret = handle;
+
+ if(utf8_name!=NULL) {
+ mutex_handle->sharedns.name=_wapi_handle_scratch_store (
+ utf8_name, strlen (utf8_name));
+ }
+
+ if(owned==TRUE) {
+ mutex_own (handle);
+ } else {
+ _wapi_handle_set_signal_state (handle, TRUE, FALSE);
}
- return(handle);
+#ifdef DEBUG
+ g_message (G_GNUC_PRETTY_FUNCTION ": returning mutex handle %p",
+ handle);
+#endif
+
+ if(utf8_name!=NULL) {
+ g_free (utf8_name);
+ }
+
+handle_cleanup:
+ thr_ret = _wapi_handle_unlock_handle (handle);
+ g_assert (thr_ret == 0);
+ pthread_cleanup_pop (0);
+
+cleanup:
+ thr_ret = mono_mutex_unlock (&named_mutex_mutex);
+ g_assert (thr_ret == 0);
+ pthread_cleanup_pop (0);
+
+ return(ret);
}
/**
* Return value: %TRUE on success, %FALSE otherwise. This function
* fails if the calling thread does not own the mutex @handle.
*/
-gboolean ReleaseMutex(WapiHandle *handle)
+gboolean ReleaseMutex(gpointer handle)
{
- struct _WapiHandle_mutex *mutex_handle=(struct _WapiHandle_mutex *)handle;
+ struct _WapiHandle_mutex *mutex_handle;
+ gboolean ok;
pthread_t tid=pthread_self();
+ pid_t pid=getpid ();
+ int thr_ret;
+ gboolean ret = FALSE;
+
+ ok=_wapi_lookup_handle (handle, WAPI_HANDLE_MUTEX,
+ (gpointer *)&mutex_handle, NULL);
+ if(ok==FALSE) {
+ g_warning (G_GNUC_PRETTY_FUNCTION
+ ": error looking up mutex handle %p", handle);
+ return(FALSE);
+ }
+
+ pthread_cleanup_push ((void(*)(void *))_wapi_handle_unlock_handle,
+ handle);
+ thr_ret = _wapi_handle_lock_handle (handle);
+ g_assert (thr_ret == 0);
#ifdef DEBUG
g_message(G_GNUC_PRETTY_FUNCTION ": Releasing mutex handle %p",
- mutex_handle);
+ handle);
#endif
- if(mutex_handle->tid!=tid) {
+ if(mutex_handle->tid!=tid || mutex_handle->pid!=pid) {
#ifdef DEBUG
- g_message(G_GNUC_PRETTY_FUNCTION ": We don't own mutex handle %p (owned by %ld, me %ld)", mutex_handle, mutex_handle->tid, tid);
+ g_message(G_GNUC_PRETTY_FUNCTION ": We don't own mutex handle %p (owned by %d:%ld, me %d:%ld)", handle, mutex_handle->pid, mutex_handle->tid, pid, tid);
#endif
- return(FALSE);
+ goto cleanup;
}
-
+ ret = TRUE;
+
/* OK, we own this mutex */
mutex_handle->recursion--;
if(mutex_handle->recursion==0) {
#ifdef DEBUG
g_message(G_GNUC_PRETTY_FUNCTION ": Unlocking mutex handle %p",
- mutex_handle);
+ handle);
#endif
+ mutex_handle->pid=0;
mutex_handle->tid=0;
- pthread_mutex_unlock(&mutex_handle->mutex);
+ _wapi_handle_set_signal_state (handle, TRUE, FALSE);
}
+
+cleanup:
+ thr_ret = _wapi_handle_unlock_handle (handle);
+ g_assert (thr_ret == 0);
+ pthread_cleanup_pop (0);
- return(TRUE);
+ return(ret);
}
projects / mono.git / blobdiff