ex_thread_pool_discard.c File Reference

destroy_threaded_pool() does not drop queued jobs silently. More...

#include "nilorea/n_common.h"
#include "nilorea/n_log.h"
#include "nilorea/n_thread_pool.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

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Functions
static void	discard_job (void *p)
	Discard function: releases a param that will never be run.
int	main (void)
static int	run (unsigned int delay)
	Queue four slow jobs on a one thread pool and destroy it.
static void *	slow_job (void *p)
	A job that takes 300 ms and releases its own param.

Variables
static pthread_mutex_t	count_lock = PTHREAD_MUTEX_INITIALIZER
	Guards the two counters.
static int	discarded = 0
static int	ran = 0
	Jobs that ran, and params the discard function released.

Detailed Description

destroy_threaded_pool() does not drop queued jobs silently.

One thread, one slow job running and three queued behind it. With a retry budget shorter than the running job, destroy gives up waiting, joins the thread - which still waits for the running job - and discards the three queued ones without running them. Their params used to go with them, unreleased and unmentioned; under a leak checker that was three leaks and nowhere else was it visible.

Now each discarded param is handed to the pool's discard function. This checks that exactly the three queued jobs are discarded, that the running one completes, and that a budget long enough to drain the queue runs all four and discards none. Run under ASan, a param that nobody releases fails the run.

Author

Castagnier Mickael

Version

1.0

Date

22/09/2026

Definition in file ex_thread_pool_discard.c.

Function Documentation

discard_job()

void discard_job ( void * p )

static

Discard function: releases a param that will never be run.

Parameters

p	A malloc'd int.

Definition at line 65 of file ex_thread_pool_discard.c.

References count_lock, and discarded.

Referenced by run().

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main()

int main

(

void

)

Definition at line 98 of file ex_thread_pool_discard.c.

References discarded, failures, LOG_NULL, ran, run, and set_log_level().

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run()

int run ( unsigned int delay )

static

Queue four slow jobs on a one thread pool and destroy it.

Parameters

delay

destroy_threaded_pool()'s retry delay, in microseconds.

Returns

0 when every job was set up, 1 otherwise.

Definition at line 77 of file ex_thread_pool_discard.c.

References add_threaded_process(), destroy_threaded_pool(), discard_job(), discarded, new_thread_pool(), NORMAL_PROC, pool, ran, set_thread_pool_discard(), and slow_job().

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slow_job()

void * slow_job ( void * p )

static

A job that takes 300 ms and releases its own param.

Parameters

p	A malloc'd int.

Returns

NULL

Definition at line 52 of file ex_thread_pool_discard.c.

References count_lock, and ran.

Referenced by run().

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Variable Documentation

count_lock

pthread_mutex_t count_lock = PTHREAD_MUTEX_INITIALIZER

static

Guards the two counters.

Definition at line 45 of file ex_thread_pool_discard.c.

Referenced by discard_job(), and slow_job().

discarded

int discarded = 0

static

Definition at line 43 of file ex_thread_pool_discard.c.

Referenced by discard_job(), main(), and run().

ran

int ran = 0

static

Jobs that ran, and params the discard function released.

Definition at line 43 of file ex_thread_pool_discard.c.

Referenced by main(), run(), and slow_job().