tc_capture.h File Reference

Test output capture helper. More...

#include <stdbool.h>
#include <stddef.h>

Go to the source code of this file.

Functions
void	tc_capture_start (void)
	Start capturing test output.
void	tc_capture_stop (void)
	Stop capturing test output.
bool	tc_capture_contains (const char *substr)
	Check whether the captured output contains a substring.
size_t	tc_capture_get (char *dst, size_t size)
	Copy the captured output into a caller-provided buffer.
void	tc_capture_clear (void)
	Discard any captured output without stopping capture.

Detailed Description

Test output capture helper.

Captures the textual diagnostic output produced during a test into an in-memory buffer so it can be asserted on, without each test having to wire up its own log backend or printk hook. Both output routes are handled transparently:

• printk() output (and logging in CONFIG_LOG_MODE_MINIMAL, which is routed through printk) is captured by wrapping the printk character-output hook.
• Full logging output ( CONFIG_LOG with a real backend mode) is captured through a dedicated log backend.

Typical use:

tc_capture_start();
do_something_that_prints();
tc_capture_stop();
zassert_true(tc_capture_contains("expected text"));

Note

When capturing logging output, the message must reach the backend before tc_capture_stop() is called. Use CONFIG_LOG_MODE_IMMEDIATE (or otherwise flush the logs) so deferred messages are not missed.

Function Documentation

tc_capture_clear()

void tc_capture_clear

(

void

)

Discard any captured output without stopping capture.

tc_capture_contains()

bool tc_capture_contains

(

const char *

substr

)

Check whether the captured output contains a substring.

Parameters

substr

NUL-terminated substring to search for.

Return values

true	if substr is present in the captured output.
false	otherwise.

tc_capture_get()

size_t tc_capture_get	(	char *	dst,
		size_t	size )

Copy the captured output into a caller-provided buffer.

The copy is always NUL-terminated (unless size is 0) and is truncated to fit size.

Parameters

dst	Destination buffer.
size	Size of dst in bytes.

Returns

Number of bytes copied, excluding the NUL terminator.

tc_capture_start()

void tc_capture_start

(

void

)

Start capturing test output.

Clears any previously captured data and begins recording printk and logging output into the internal capture buffer. Capturing continues until tc_capture_stop() is called. Output is still forwarded to the normal console so ordinary test logs are unaffected.

tc_capture_stop()

void tc_capture_stop

(

void

)

Stop capturing test output.

Restores the normal output path. The captured data remains available for inspection with tc_capture_contains() and tc_capture_get() until the next tc_capture_start() or tc_capture_clear().