#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#ifdef ENABLE_THREADS
#include <pthread.h>
#endif
#include <glib.h>
#include "camel-operation.h"
#include "e-util/e-msgport.h"
#define d(x)
/* ********************************************************************** */
struct _CamelOperation {
pthread_t id; /* id of running thread */
guint32 flags; /* cancelled ? */
int blocked; /* cancellation blocked depth */
int refcount;
CamelOperationStatusFunc status;
void *status_data;
time_t status_update;
/* stack of status messages (char *) */
GSList *status_stack;
#ifdef ENABLE_THREADS
EMsgPort *cancel_port;
int cancel_fd;
pthread_mutex_t lock;
#endif
};
#define CAMEL_OPERATION_CANCELLED (1<<0)
#ifdef ENABLE_THREADS
#define CAMEL_OPERATION_LOCK(cc) pthread_mutex_lock(&cc->lock)
#define CAMEL_OPERATION_UNLOCK(cc) pthread_mutex_unlock(&cc->lock)
#define CAMEL_ACTIVE_LOCK() pthread_mutex_lock(&operation_active_lock)
#define CAMEL_ACTIVE_UNLOCK() pthread_mutex_unlock(&operation_active_lock)
static pthread_mutex_t operation_active_lock = PTHREAD_MUTEX_INITIALIZER;
#else
#define CAMEL_OPERATION_LOCK(cc)
#define CAMEL_OPERATION_UNLOCK(cc)
#define CAMEL_ACTIVE_LOCK()
#define CAMEL_ACTIVE_UNLOCK()
#endif
static GHashTable *operation_active;
typedef struct _CamelOperationMsg {
EMsg msg;
} CamelOperationMsg ;
/**
* camel_operation_new:
* @status: Callback for receiving status messages.
* @status_data: User data.
*
* Create a new camel operation handle. Camel operation handles can
* be used in a multithreaded application (or a single operation
* handle can be used in a non threaded appliation) to cancel running
* operations and to obtain notification messages of the internal
* status of messages.
*
* Return value: A new operation handle.
**/
CamelOperation *camel_operation_new(CamelOperationStatusFunc status, void *status_data)
{
CamelOperation *cc;
cc = g_malloc0(sizeof(*cc));
cc->flags = 0;
cc->blocked = 0;
cc->refcount = 1;
cc->status = status;
cc->status_data = status_data;
#ifdef ENABLE_THREADS
cc->id = ~0;
cc->cancel_port = e_msgport_new();
cc->cancel_fd = e_msgport_fd(cc->cancel_port);
pthread_mutex_init(&cc->lock, NULL);
#endif
return cc;
}
/**
* camel_operation_reset:
* @cc:
*
* Resets an operation cancel state and message.
**/
void camel_operation_reset(CamelOperation *cc)
{
GSList *n;
#ifdef ENABLE_THREADS
CamelOperationMsg *msg;
while ((msg = (CamelOperationMsg *)e_msgport_get(cc->cancel_port)))
g_free(msg);
#endif
n = cc->status_stack;
while (n) {
g_free(n->data);
n = n->next;
}
g_slist_free(cc->status_stack);
cc->status_stack = NULL;
cc->flags = 0;
cc->blocked = 0;
}
/**
* camel_operation_ref:
* @cc:
*
* Add a reference to the CamelOperation @cc.
**/
void camel_operation_ref(CamelOperation *cc)
{
CAMEL_OPERATION_LOCK(cc);
cc->refcount++;
CAMEL_OPERATION_UNLOCK(cc);
}
/**
* camel_operation_unref:
* @cc:
*
* Unref and potentially free @cc.
**/
void camel_operation_unref(CamelOperation *cc)
{
GSList *n;
#ifdef ENABLE_THREADS
CamelOperationMsg *msg;
if (cc->refcount == 1) {
while ((msg = (CamelOperationMsg *)e_msgport_get(cc->cancel_port)))
g_free(msg);
e_msgport_destroy(cc->cancel_port);
#endif
n = cc->status_stack;
while (n) {
g_warning("Camel operation status stack non empty: %s", (char *)n->data);
g_free(n->data);
n = n->next;
}
g_slist_free(cc->status_stack);
g_free(cc);
} else {
CAMEL_OPERATION_LOCK(cc);
cc->refcount--;
CAMEL_OPERATION_UNLOCK(cc);
}
}
/**
* camel_operation_cancel_block:
* @cc:
*
* Block cancellation for this operation. If @cc is NULL, then the
* current thread is blocked.
**/
void camel_operation_cancel_block(CamelOperation *cc)
{
CAMEL_ACTIVE_LOCK();
if (operation_active == NULL)
operation_active = g_hash_table_new(NULL, NULL);
if (cc == NULL)
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc) {
CAMEL_OPERATION_LOCK(cc);
cc->blocked++;
CAMEL_OPERATION_UNLOCK(cc);
}
}
/**
* camel_operation_cancel_unblock:
* @cc:
*
* Unblock cancellation, when the unblock count reaches the block
* count, then this operation can be cancelled. If @cc is NULL, then
* the current thread is unblocked.
**/
void camel_operation_cancel_unblock(CamelOperation *cc)
{
CAMEL_ACTIVE_LOCK();
if (operation_active == NULL)
operation_active = g_hash_table_new(NULL, NULL);
if (cc == NULL)
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc) {
CAMEL_OPERATION_LOCK(cc);
cc->blocked--;
CAMEL_OPERATION_UNLOCK(cc);
}
}
static void
cancel_thread(void *key, CamelOperation *cc, void *data)
{
if (cc)
camel_operation_cancel(cc);
}
/**
* camel_operation_cancel:
* @cc:
*
* Cancel a given operation. If @cc is NULL then all outstanding
* operations are cancelled.
**/
void camel_operation_cancel(CamelOperation *cc)
{
CamelOperationMsg *msg;
if (cc == NULL) {
if (operation_active) {
CAMEL_ACTIVE_LOCK();
g_hash_table_foreach(operation_active, (GHFunc)cancel_thread, NULL);
CAMEL_ACTIVE_UNLOCK();
}
} else if ((cc->flags & CAMEL_OPERATION_CANCELLED) == 0) {
d(printf("cancelling thread %d\n", cc->id));
CAMEL_OPERATION_LOCK(cc);
msg = g_malloc0(sizeof(*msg));
e_msgport_put(cc->cancel_port, (EMsg *)msg);
cc->flags |= CAMEL_OPERATION_CANCELLED;
CAMEL_OPERATION_UNLOCK(cc);
}
}
/**
* camel_operation_register:
* @cc:
*
* Register a thread or the main thread for cancellation through @cc.
* If @cc is NULL, then a new cancellation is created for this thread,
* but may only be cancelled from the same thread.
*
* All calls to operation_register() should be matched with calls to
* operation_unregister(), or resources will be lost.
**/
void camel_operation_register(CamelOperation *cc)
{
pthread_t id = pthread_self();
CAMEL_ACTIVE_LOCK();
if (operation_active == NULL)
operation_active = g_hash_table_new(NULL, NULL);
if (cc == NULL) {
cc = g_hash_table_lookup(operation_active, (void *)id);
if (cc == NULL) {
cc = camel_operation_new(NULL, NULL);
}
}
cc->id = id;
g_hash_table_insert(operation_active, (void *)id, cc);
d(printf("registering thread %ld for cancellation\n", id));
CAMEL_ACTIVE_UNLOCK();
camel_operation_ref(cc);
}
/**
* camel_operation_unregister:
* @cc:
*
* Unregister a given operation from being cancelled. If @cc is NULL,
* then the current thread is used.
**/
void camel_operation_unregister(CamelOperation *cc)
{
CAMEL_ACTIVE_LOCK();
if (operation_active == NULL)
operation_active = g_hash_table_new(NULL, NULL);
if (cc == NULL) {
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
if (cc == NULL) {
g_warning("Trying to unregister a thread that was never registered for cancellation");
}
}
if (cc)
g_hash_table_remove(operation_active, (void *)cc->id);
CAMEL_ACTIVE_UNLOCK();
d({if (cc) printf("unregistering thread %d for cancellation\n", cc->id);});
if (cc)
camel_operation_unref(cc);
}
/**
* camel_operation_cancel_check:
* @cc:
*
* Check if cancellation has been applied to @cc. If @cc is NULL,
* then the CamelOperation registered for the current thread is used.
*
* Return value: TRUE if the operation has been cancelled.
**/
gboolean camel_operation_cancel_check(CamelOperation *cc)
{
CamelOperationMsg *msg;
d(printf("checking for cancel in thread %d\n", pthread_self()));
if (cc == NULL) {
if (operation_active) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
}
if (cc == NULL)
return FALSE;
}
if (cc->blocked > 0) {
d(printf("ahah! cancellation is blocked\n"));
return FALSE;
}
if (cc->flags & CAMEL_OPERATION_CANCELLED) {
d(printf("previously cancelled\n"));
return TRUE;
}
msg = (CamelOperationMsg *)e_msgport_get(cc->cancel_port);
if (msg) {
d(printf("Got cancellation message\n"));
CAMEL_OPERATION_LOCK(cc);
cc->flags |= CAMEL_OPERATION_CANCELLED;
CAMEL_OPERATION_UNLOCK(cc);
return TRUE;
}
return FALSE;
}
/**
* camel_operation_cancel_fd:
* @cc:
*
* Retrieve a file descriptor that can be waited on (select, or poll)
* for read, to asynchronously detect cancellation.
*
* Return value: The fd, or -1 if cancellation is not available
* (blocked, or has not been registered for this thread).
**/
int camel_operation_cancel_fd(CamelOperation *cc)
{
if (cc == NULL) {
if (operation_active) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
}
if (cc == NULL)
return -1;
}
if (cc->blocked)
return -1;
return cc->cancel_fd;
}
/**
* camel_operation_start:
* @cc:
* @what:
* @:
*
* Report the start of an operation. All start operations should have
* similar end operations.
**/
void camel_operation_start(CamelOperation *cc, char *what, ...)
{
va_list ap;
char *msg;
if (operation_active == NULL)
return;
if (cc == NULL) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc == NULL)
return;
}
if (cc->status == NULL)
return;
va_start(ap, what);
msg = g_strdup_vprintf(what, ap);
va_end(ap);
cc->status(cc, msg, CAMEL_OPERATION_START, cc->status_data);
cc->status_update = 0;
cc->status_stack = g_slist_prepend(cc->status_stack, msg);
d(printf("start '%s'\n", msg, pc));
}
/**
* camel_operation_progress:
* @cc: Operation to report to.
* @pc: Percent complete, 0 to 100.
*
* Report progress on the current operation. If @cc is NULL, then the
* currently registered operation is used. @pc reports the current
* percentage of completion, which should be in the range of 0 to 100.
*
* If the total percentage is not know, then use
* camel_operation_progress_count().
**/
void camel_operation_progress(CamelOperation *cc, int pc)
{
char *msg;
time_t now;
if (operation_active == NULL)
return;
if (cc == NULL) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc == NULL)
return;
}
if (cc->status == NULL)
return;
if (cc->status_stack == NULL)
return;
now = time(0);
if (cc->status_update != now) {
msg =cc->status_stack->data;
cc->status(cc, msg, pc, cc->status_data);
d(printf("progress '%s' %d %%\n", msg, pc));
cc->status_update = now;
}
}
void camel_operation_progress_count(CamelOperation *cc, int sofar)
{
char *msg;
time_t now;
if (operation_active == NULL)
return;
if (cc == NULL) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc == NULL)
return;
}
if (cc->status == NULL)
return;
if (cc->status_stack == NULL)
return;
/* FIXME: generate some meaningful pc value */
now = time(0);
if (cc->status_update != now) {
msg =cc->status_stack->data;
cc->status(cc, msg, sofar, cc->status_data);
d(printf("progress '%s' %d done\n", msg, sofar));
cc->status_update = now;
}
}
/**
* camel_operation_end:
* @cc:
* @what: Format string.
* @:
*
* Report the end of an operation. If @cc is NULL, then the currently
* registered operation is notified.
**/
void camel_operation_end(CamelOperation *cc)
{
char *msg;
if (operation_active == NULL)
return;
if (cc == NULL) {
CAMEL_ACTIVE_LOCK();
cc = g_hash_table_lookup(operation_active, (void *)pthread_self());
CAMEL_ACTIVE_UNLOCK();
if (cc == NULL)
return;
}
if (cc->status == NULL)
return;
if (cc->status_stack == NULL)
return;
msg = cc->status_stack->data;
cc->status(cc, msg, CAMEL_OPERATION_END, cc->status_data);
g_free(msg);
cc->status_stack = g_slist_remove_link(cc->status_stack, cc->status_stack);
}
