Wyatt Hepler | f9fb90f | 2020-09-30 18:59:33 -0700 | [diff] [blame] | 1 | .. _module-pw_log_tokenized: |
Keir Mierle | bc5a269 | 2020-05-21 16:52:25 -0700 | [diff] [blame] | 2 | |
Wyatt Hepler | cb725c1 | 2020-05-01 11:05:01 -0700 | [diff] [blame] | 3 | ---------------- |
| 4 | pw_log_tokenized |
| 5 | ---------------- |
| 6 | ``pw_log_tokenized`` is a ``pw_log`` backend that tokenizes log messages using |
| 7 | the ``pw_tokenizer`` module. Log messages are tokenized and passed to the |
Wyatt Hepler | 7a5e4d6 | 2020-08-31 08:39:16 -0700 | [diff] [blame] | 8 | ``pw_tokenizer_HandleEncodedMessageWithPayload`` function. For maximum |
Wyatt Hepler | cb725c1 | 2020-05-01 11:05:01 -0700 | [diff] [blame] | 9 | efficiency, the log level, 16-bit tokenized module name, and flags bits are |
| 10 | passed through the payload argument. |
| 11 | |
| 12 | Example implementation: |
| 13 | |
| 14 | .. code-block:: cpp |
| 15 | |
Wyatt Hepler | 7a5e4d6 | 2020-08-31 08:39:16 -0700 | [diff] [blame] | 16 | extern "C" void pw_tokenizer_HandleEncodedMessageWithPayload( |
| 17 | pw_tokenizer_Payload payload, const uint8_t message[], size_t size) { |
Wyatt Hepler | cb725c1 | 2020-05-01 11:05:01 -0700 | [diff] [blame] | 18 | // The metadata object provides the log level, module token, and flags. |
| 19 | // These values can be recorded and used for runtime filtering. |
| 20 | pw::log_tokenized::Metadata metadata(payload); |
| 21 | |
| 22 | if (metadata.level() < current_log_level) { |
| 23 | return; |
| 24 | } |
| 25 | |
| 26 | if (metadata.flags() & HIGH_PRIORITY_LOG != 0) { |
| 27 | EmitHighPriorityLog(metadata.module(), message, size); |
| 28 | } else { |
| 29 | EmitLowPriorityLog(metadata.module(), message, size); |
| 30 | } |
| 31 | } |
| 32 | |
| 33 | See the documentation for ``pw_tokenizer`` for further details. |
| 34 | |
Wyatt Hepler | 6736887 | 2020-07-30 16:55:38 -0700 | [diff] [blame] | 35 | Build targets |
| 36 | ------------- |
| 37 | The GN build for ``pw_log_tokenized`` has two targets: ``pw_log_tokenized`` and |
| 38 | ``log_backend``. The ``pw_log_tokenized`` target provides the |
| 39 | ``pw_log_tokenized/log_tokenized.h`` header. The ``log_backend`` target |
| 40 | implements the backend for the ``pw_log`` facade. ``pw_log_tokenized`` invokes |
Wyatt Hepler | e0575f7 | 2020-10-16 10:47:03 -0700 | [diff] [blame] | 41 | the ``pw_tokenizer:global_handler_with_payload`` facade, which must be |
Wyatt Hepler | 6736887 | 2020-07-30 16:55:38 -0700 | [diff] [blame] | 42 | implemented by the user of ``pw_log_tokenized``. |
| 43 | |
Wyatt Hepler | cb725c1 | 2020-05-01 11:05:01 -0700 | [diff] [blame] | 44 | .. note:: |
| 45 | The documentation for this module is currently incomplete. |