fix a whole bunch of memory leaks

libretro-common/include/queues/task_queue.h

@@ -209,8 +209,10 @@ void task_queue_retrieve(task_retriever_data_t *data);
 void task_queue_check(void);
 
 /* Pushes a task
- * The task will start as soon as possible. */
-void task_queue_push(retro_task_t *task);
+ * The task will start as soon as possible.
+ * If a second blocking task is attempted, false will be returned
+ * and the task will be ignored. */
+bool task_queue_push(retro_task_t *task);
 
 /* Blocks until all tasks have finished
  * will return early if cond is not NULL

libretro-common/queues/task_queue.c

@@ -610,7 +610,7 @@ void task_queue_check(void)
    impl_current->gather();
 }
 
-void task_queue_push(retro_task_t *task)
+bool task_queue_push(retro_task_t *task)
 {
    /* Ignore this task if a related one is already running */
    if (task->type == TASK_TYPE_BLOCKING)
@@ -634,12 +634,14 @@ void task_queue_push(retro_task_t *task)
 
       /* skip this task, user must try again later */
       if (found)
-         return;
+         return false;
    }
 
    /* The lack of NULL checks in the following functions
     * is proposital to ensure correct control flow by the users. */
    impl_current->push_running(task);
+
+   return true;
 }
 
 void task_queue_wait(retro_task_condition_fn_t cond, void* data)

tasks/task_save.c

@@ -511,6 +511,8 @@ static void undo_save_state_cb(retro_task_t *task,
       void *task_data,
       void *user_data, const char *error)
 {
+   save_task_state_t *state = (save_task_state_t*)task_data;
+
    /* Wipe the save file buffer as it's intended to be one use only */
    undo_save_buf.path[0] = '\0';
    undo_save_buf.size    = 0;
@@ -519,6 +521,8 @@ static void undo_save_state_cb(retro_task_t *task,
       free(undo_save_buf.data);
       undo_save_buf.data = NULL;
    }
+
+   free(state);
 }
 
 /**
@@ -563,6 +567,9 @@ void* get_serialized_data(const char *path, size_t serial_size)
    bool ret    = false;
    void *data  = NULL;
 
+   if (!serial_size)
+      return NULL;
+
    data = malloc(serial_size);
 
    if (!data)
@@ -576,11 +583,13 @@ void* get_serialized_data(const char *path, size_t serial_size)
    serial_info.data = data;
    serial_info.size = serial_size;
    ret              = core_serialize(&serial_info);
+
    if (!ret)
    {
       free(data);
       return NULL;
    }
+
    return data;
 }
 
@@ -1054,6 +1063,7 @@ static void save_state_cb(retro_task_t *task,
       take_screenshot(path, true, state->has_valid_framebuffer, false, true);
 
    free(path);
+   free(state);
 }
 
 /**
@@ -1089,7 +1099,16 @@ static void task_push_save_state(const char *path, void *data, size_t size, bool
    task->title             = strdup(msg_hash_to_str(MSG_SAVING_STATE));
    task->mute              = state->mute;
 
-   task_queue_push(task);
+   if (!task_queue_push(task))
+   {
+      /* Another blocking task is already active. */
+      if (data)
+         free(data);
+      if (task->title)
+         task_free_title(task);
+      free(task);
+      free(state);
+   }
 
    return;
 
@@ -1099,8 +1118,12 @@ error:
    if (state)
       free(state);
    if (task)
+   {
+      if (task->title)
+         task_free_title(task);
       free(task);
    }
+}
 
 /**
  * content_load_and_save_state_cb:
@@ -1163,7 +1186,16 @@ static void task_push_load_and_save_state(const char *path, void *data,
    task->title       = strdup(msg_hash_to_str(MSG_LOADING_STATE));
    task->mute        = state->mute;
 
-   task_queue_push(task);
+   if (!task_queue_push(task))
+   {
+      /* Another blocking task is already active. */
+      if (data)
+         free(data);
+      if (task->title)
+         task_free_title(task);
+      free(task);
+      free(state);
+   }
 
    return;
 
@@ -1214,7 +1246,6 @@ bool content_save_state(const char *path, bool save_to_disk, bool autosave)
             msg_hash_to_str(MSG_STATE_SIZE),
             (int)info.size,
             msg_hash_to_str(MSG_BYTES));
-
    }
 
    if (save_to_disk)

tasks/task_screenshot.c

@@ -49,6 +49,7 @@
 #include "../retroarch.h"
 #include "../paths.h"
 #include "../msg_hash.h"
+#include "../verbosity.h"
 
 #include "../gfx/video_driver.h"
 
@@ -143,6 +144,9 @@ static void task_screenshot_handler(retro_task_t *task)
    {
       task_set_finished(task, true);
 
+      if (task->title)
+         task_free_title(task);
+
       if (state->userbuf)
          free(state->userbuf);
 
@@ -173,6 +177,9 @@ static void task_screenshot_handler(retro_task_t *task)
       runloop_msg_queue_push(msg, 1, state->is_paused ? 1 : 180, true, NULL, MESSAGE_QUEUE_ICON_DEFAULT, MESSAGE_QUEUE_CATEGORY_INFO);
       free(msg);
    }
+
+   if (task->title)
+      task_free_title(task);
 }
 
 /* Take frame bottom-up. */
@@ -191,18 +198,20 @@ static bool screenshot_dump(
    char screenshot_path[PATH_MAX_LENGTH];
    uint8_t *buf                   = NULL;
    settings_t *settings           = config_get_ptr();
-   retro_task_t *task             = task_init();
-   screenshot_task_state_t *state = (screenshot_task_state_t*)
-         calloc(1, sizeof(*state));
+   retro_task_t *task;
+   screenshot_task_state_t *state;
    const char *screenshot_dir     = settings->paths.directory_screenshot;
    struct retro_system_info system_info;
 
-   state->shotname[0]             = '\0';
    screenshot_path[0]             = '\0';
 
    if (!core_get_system_info(&system_info))
       return false;
 
+   task = task_init();
+   state = (screenshot_task_state_t*)calloc(1, sizeof(*state));
+   state->shotname[0] = '\0';
+
    /* If fullpath is true, name_base already contains a static path + filename to save the screenshot to. */
    if (fullpath)
       strlcpy(state->filename, name_base, sizeof(state->filename));
@@ -282,10 +291,28 @@ static bool screenshot_dump(
       if (!savestate)
          task->title = strdup(msg_hash_to_str(MSG_TAKING_SCREENSHOT));
 
-      task_queue_push(task);
+      if (!task_queue_push(task))
+      {
+         /* There is already a blocking task going on */
+         if (task->title)
+            task_free_title(task);
+
+         free(task);
+
+         if (state->out_buffer)
+            free(state->out_buffer);
+
+         free(state);
+
+         return false;
+      }
    }
    else
+   {
+      if (task)
+         free(task);
       return screenshot_dump_direct(state);
+   }
 
    return true;
 }