Merge pull request #2952 from leiradel/master

http tasks can now be cancelled

libretro-common/include/queues/task_queue.h

@@ -82,8 +82,13 @@ enum task_queue_ctl_state
 
    TASK_QUEUE_CTL_UNSET_THREADED,
 
-   TASK_QUEUE_CTL_IS_THREADED
-};
+   TASK_QUEUE_CTL_IS_THREADED,
+   
+   /**
+    * Signals a task to end without waiting for
+    * it to complete. */
+   TASK_QUEUE_CTL_CANCEL,
+ };
 
 typedef struct retro_task retro_task_t;
 typedef void (*retro_task_callback_t)(void *task_data,
@@ -148,6 +153,8 @@ void task_queue_push_progress(retro_task_t *task);
 
 bool task_queue_ctl(enum task_queue_ctl_state state, void *data);
 
+void task_queue_cancel_task(void *task);
+
 RETRO_END_DECLS
 
 #endif

libretro-common/queues/task_queue.c

@@ -39,6 +39,7 @@ typedef struct
 struct retro_task_impl
 {
    void (*push_running)(retro_task_t *);
+   void (*cancel)(void *);
    void (*reset)(void);
    void (*wait)(void);
    void (*gather)(void);
@@ -167,6 +168,12 @@ static void retro_task_regular_push_running(retro_task_t *task)
    task_queue_put(&tasks_running, task);
 }
 
+static void retro_task_regular_cancel(void *task)
+{
+   retro_task_t *t = task;
+   t->cancelled = true;
+}
+ 
 static void retro_task_regular_gather(void)
 {
    retro_task_t *task  = NULL;
@@ -232,6 +239,7 @@ static bool retro_task_regular_find(retro_task_finder_t func, void *user_data)
 
 static struct retro_task_impl impl_regular = {
    retro_task_regular_push_running,
+   retro_task_regular_cancel,
    retro_task_regular_reset,
    retro_task_regular_wait,
    retro_task_regular_gather,
@@ -255,6 +263,24 @@ static void retro_task_threaded_push_running(retro_task_t *task)
    slock_unlock(running_lock);
 }
 
+static void retro_task_threaded_cancel(void *task)
+{
+   retro_task_t *t;
+
+   slock_lock(running_lock);
+   
+   for (t = tasks_running.front; t; t = t->next)
+   {
+      if (t == task)
+      {
+        t->cancelled = true;
+        break;
+      }
+   }
+
+   slock_unlock(running_lock);
+}
+
 static void retro_task_threaded_gather(void)
 {
    retro_task_t *task = NULL;
@@ -399,6 +425,7 @@ static void retro_task_threaded_deinit(void)
 
 static struct retro_task_impl impl_threaded = {
    retro_task_threaded_push_running,
+   retro_task_threaded_cancel,
    retro_task_threaded_reset,
    retro_task_threaded_wait,
    retro_task_threaded_gather,
@@ -484,6 +511,9 @@ bool task_queue_ctl(enum task_queue_ctl_state state, void *data)
       case TASK_QUEUE_CTL_WAIT:
          impl_current->wait();
          break;
+      case TASK_QUEUE_CTL_CANCEL:
+         impl_current->cancel(data);
+         break;
       case TASK_QUEUE_CTL_NONE:
       default:
          break;
@@ -491,3 +521,8 @@ bool task_queue_ctl(enum task_queue_ctl_state state, void *data)
 
    return true;
 }
+
+void task_queue_cancel_task(void *task)
+{
+   task_queue_ctl(TASK_QUEUE_CTL_CANCEL, task);
+}

tasks/task_http.c

@@ -127,6 +127,9 @@ static void rarch_task_http_transfer_handler(retro_task_t *task)
    http_handle_t *http = (http_handle_t*)task->state;
    http_transfer_data_t *data;
 
+   if (task->cancelled)
+      goto task_finished;
+
    switch (http->status)
    {
       case HTTP_STATUS_CONNECTION_TRANSFER_PARSE:
@@ -148,7 +151,7 @@ static void rarch_task_http_transfer_handler(retro_task_t *task)
          break;
    }
 
-   if (task->cancelled || http->error)
+   if (http->error)
       goto task_finished;
 
    return;
@@ -251,7 +254,7 @@ static bool rarch_task_http_retriever(retro_task_t *task, void *user_data)
    return false;
 }
 
-bool rarch_task_push_http_transfer(const char *url, const char *type,
+void *rarch_task_push_http_transfer(const char *url, const char *type,
       retro_task_callback_t cb, void *user_data)
 {
    char tmp[PATH_MAX_LENGTH];
@@ -261,7 +264,7 @@ bool rarch_task_push_http_transfer(const char *url, const char *type,
    http_handle_t *http            = NULL;
 
    if (string_is_empty(url))
-      return false;
+      return NULL;
 
    find_data.func     = rarch_task_http_finder;
    find_data.userdata = (void*)url;
@@ -270,13 +273,13 @@ bool rarch_task_push_http_transfer(const char *url, const char *type,
    if (task_queue_ctl(TASK_QUEUE_CTL_FIND, &find_data))
    {
       RARCH_LOG("[http] '%s'' is already being downloaded.\n", url);
-      return false;
+      return NULL;
    }
 
    conn = net_http_connection_new(url);
 
    if (!conn)
-      return false;
+      return NULL;
 
    http                    = (http_handle_t*)calloc(1, sizeof(*http));
 
@@ -310,7 +313,7 @@ bool rarch_task_push_http_transfer(const char *url, const char *type,
 
    task_queue_ctl(TASK_QUEUE_CTL_PUSH, t);
 
-   return true;
+   return t;
 
 error:
    if (conn)
@@ -320,7 +323,7 @@ error:
    if (http)
       free(http);
 
-   return false;
+   return NULL;
 }
 
 http_transfer_info_t *http_task_get_transfer_list()

tasks/tasks_internal.h

@@ -41,7 +41,7 @@ typedef struct http_transfer_info
    struct http_transfer_info *next;
 } http_transfer_info_t;
 
-bool rarch_task_push_http_transfer(const char *url, const char *type,
+void *rarch_task_push_http_transfer(const char *url, const char *type,
       retro_task_callback_t cb, void *userdata);
 
 http_transfer_info_t *http_task_get_transfer_list();