Chromium Code Reviews| Index: ppapi/c/pp_completion_callback.h |
| =================================================================== |
| --- ppapi/c/pp_completion_callback.h (revision 90953) |
| +++ ppapi/c/pp_completion_callback.h (working copy) |
| @@ -21,8 +21,14 @@ |
| */ |
| /** |
| - * PP_CompletionCallback_Func defines the signature that you implement to |
| + * This typedef defines the signature that you implement to |
| * receive callbacks on asynchronous completion. |
| + * |
| + * @param[in] user_data A pointer to user data passed to a callback function. |
| + * @param[in] result If result is 0 (PP_OK), the operation succeeded. Negative |
| + * values, other than -1, indicate error and are specified in pp_errors.h. |
|
dmichael (off chromium)
2011/06/30 10:03:48
nit: Those commas don't seem necessary to me. Pare
jond
2011/06/30 16:24:16
Done.
jond
2011/06/30 16:24:16
Done.
|
| + * Positive values for result usually indicate success and have some |
| + * operation-dependent meaning (such as bytes read). |
| */ |
| typedef void (*PP_CompletionCallback_Func)(void* user_data, int32_t result); |
| /** |
| @@ -35,22 +41,30 @@ |
| */ |
| /** |
| - * Any method that takes a PP_CompletionCallback has the option of completing |
| - * asynchronously if the operation would block. Such a method should return |
| - * PP_OK_COMPLETIONPENDING to indicate that the method will complete |
| - * asynchronously and will always be invoked from the main thread of PPAPI |
| - * execution. If the completion callback is NULL, then the operation will |
| - * block if necessary to complete its work. PP_BlockUntilComplete() provides a |
| - * convenient way to specify blocking behavior. Refer to PP_BlockUntilComplete |
| - * for more information. |
| + * Any method that takes a <code>PP_CompletionCallback</code> has the option of |
| + * completing asynchronously if the operation would block. Such a method |
| + * should return <code>PP_OK_COMPLETIONPENDING</code> to indicate that the |
| + * method will complete asynchronously and will always be invoked from the main |
| + * thread of PPAPI execution. If the completion callback is NULL, then the |
| + * operation will block if necessary to complete its work. |
| + * <code>PP_BlockUntilComplete()</code> provides a convenient way to specify |
| + * blocking behavior. Refer to <code>PP_BlockUntilComplete</code> for more |
| + * information. |
| * |
| * The result parameter passes an int32_t that, if negative or equal to 0, |
| - * indicate if the call will completely asynchronously (the callback will be |
| + * indicate if the call will complete asynchronously (the callback will be |
| * called with a status code). A value greater than zero indicates additional |
| * information such as bytes read. |
| */ |
| struct PP_CompletionCallback { |
| + /** |
| + * This value is a callback function that will be called. |
| + */ |
| PP_CompletionCallback_Func func; |
| + |
| + /** |
| + * This value is a pointer to user data passed to a callback function. |
| + */ |
| void* user_data; |
| }; |
| /** |
| @@ -63,13 +77,15 @@ |
| */ |
| /** |
| - * PP_MakeCompletionCallback() is used to create a PP_CompletionCallback. |
| + * PP_MakeCompletionCallback() is used to create a |
| + * <code>PP_CompletionCallback</code>. |
| * |
| - * @param[in] func A PP_CompletionCallback_Func that will be called. |
| + * @param[in] func A <code>PP_CompletionCallback_Func</code> that will be |
| + * called. |
| * @param[in] user_data A pointer to user data passed to your callback |
| * function. This is optional and is typically used to help track state |
| * when you may have multiple callbacks pending. |
| - * @return A PP_CompletionCallback structure. |
| + * @return A <code>PP_CompletionCallback</code> structure. |
| */ |
| PP_INLINE struct PP_CompletionCallback PP_MakeCompletionCallback( |
| PP_CompletionCallback_Func func, |
| @@ -91,7 +107,8 @@ |
| /** |
| * PP_RunCompletionCallback() is used to run a callback. |
| * |
| - * @param[in] cc A pointer to a PP_CompletionCallback that will be run. |
| + * @param[in] cc A pointer to a <code>PP_CompletionCallback</code> that will be |
| + * run. |
| * @param[in] res The result parameter that, if negative or equal to 0, |
| * indicate if the call will completely asynchronously (the callback will be |
| * called with a status code). A value greater than zero indicates additional |
| @@ -117,24 +134,24 @@ |
| * until the function completes. Blocking completion callbacks are only usable |
| * from background threads. |
| * |
| - * @return A PP_CompletionCallback structure. |
| + * @return A <code>PP_CompletionCallback</code> structure. |
| */ |
| PP_INLINE struct PP_CompletionCallback PP_BlockUntilComplete() { |
| return PP_MakeCompletionCallback(NULL, NULL); |
| } |
| /** |
| - * Runs a callback and clears the reference to it. |
| + * PP_RunAndClearCompletionCallback() runs a callback and clears the reference |
| + * to that callback. |
| * |
| - * This is used when the null-ness of a completion callback is used as a signal |
| - * for whether a completion callback has been registered. In this case, after |
| - * the execution of the callback, it should be cleared. |
| - * |
| - * However, this introduces a conflict if the completion callback wants to |
| - * schedule more work that involves the same completion callback again (for |
| - * example, when reading data from an URLLoader, one would typically queue up |
| + * This function is used when the null-ness of a completion callback is used as |
| + * a signal for whether a completion callback has been registered. In this |
| + * case, after the execution of the callback, it should be cleared. However, |
| + * this introduces a conflict if the completion callback wants to schedule more |
| + * work that involves the same completion callback again (for example, when |
| + * reading data from an URLLoader, one would typically queue up |
| * another read callback). As a result, this function clears the pointer |
| - * *before* the given callback is executed. |
| + * before the provided callback is executed. |
| */ |
| PP_INLINE void PP_RunAndClearCompletionCallback( |
| struct PP_CompletionCallback* cc, |