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/* ==========================================================================
* Licensed under BSD 2clause license See LICENSE file for more information
* Author: Michał Łyszczek <michal.lyszczek@bofc.pl>
* ==========================================================================
* ------------------------------------------------------------
* / This example uses threads. It is classic consumer-producer \
* | problem that thanks to rb internal thread awareness is |
* | reduced to minimum. Note that there is no mutex in this |
* | file, all synchronization is performed by rb. Program |
* | prints blocks representing count elements in rb to |
* | visualize how elements are popped and pushed. This example |
* \ also shows how growable buffer works. /
* ------------------------------------------------------------
* \
* \
* oO)-. .-(Oo
* /__ _\ /_ __\
* \ \( | ()~() | )/ /
* \__|\ | (-___-) | /|__/
* ' '--' ==`-'== '--' '
* ==========================================================================
* ░▀█▀░█▀█░█▀▀░█░░░█░█░█▀▄░█▀▀░█▀▀
* ░░█░░█░█░█░░░█░░░█░█░█░█░█▀▀░▀▀█
* ░▀▀▀░▀░▀░▀▀▀░▀▀▀░▀▀▀░▀▀░░▀▀▀░▀▀▀
* ========================================================================== */
#include <errno.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "rb.h"
#include "common.h"
/* ==========================================================================
* ░█▀▄░█▀▀░█▀▀░█░░░█▀█░█▀▄░█▀█░▀█▀░▀█▀░█▀█░█▀█░█▀▀
* ░█░█░█▀▀░█░░░█░░░█▀█░█▀▄░█▀█░░█░░░█░░█░█░█░█░▀▀█
* ░▀▀░░▀▀▀░▀▀▀░▀▀▀░▀░▀░▀░▀░▀░▀░░▀░░▀▀▀░▀▀▀░▀░▀░▀▀▀
* ========================================================================== */
static struct rb *rb; /* pointer to malloc()ed rb object */
static const char *bar =
"=============================================================================";
static const char *sbar =
" ";
/* ==========================================================================
* ░█▀▀░█░█░█▀█░█▀▀░▀█▀░▀█▀░█▀█░█▀█░█▀▀
* ░█▀▀░█░█░█░█░█░░░░█░░░█░░█░█░█░█░▀▀█
* ░▀░░░▀▀▀░▀░▀░▀▀▀░░▀░░▀▀▀░▀▀▀░▀░▀░▀▀▀
* ========================================================================== */
/** =========================================================================
* Consumer thread.
*
* @param arg small integer, to control how fast data is read from buffer
* ========================================================================== */
static void *consumer(void *arg)
{
struct timespec req;
int sleep_ms;
int i;
int data;
int run_time;
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
sleep_ms = *(int *)arg;
req.tv_sec = sleep_ms / 1000;
req.tv_nsec = 1000000L * (sleep_ms % 1000);
run_time = sleep_ms ? 15 : 300;
for (i = 0; i != run_time; ++i) {
if (rb_read(rb, &data, 1) != 1)
pdie("rb_read()");
/* use random time */
if (sleep_ms == 0) {
req.tv_sec = 0;
req.tv_nsec = 1000000L * (rand() % 50 + 20);
}
nanosleep(&req, NULL);
}
return NULL;
}
/** =========================================================================
* Producer thread.
*
* @param arg small integer, to control how fast data is read from buffer
* ========================================================================== */
static void *producer(void *arg)
{
struct timespec req;
int sleep_ms;
int i;
int run_time;
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
sleep_ms = *(int *)arg;
req.tv_sec = sleep_ms / 1000;
req.tv_nsec = 1000000L * (sleep_ms % 1000);
run_time = sleep_ms ? 15 : 300;
for (i = 0; i != run_time; ++i) {
if (rb_write(rb, &i, 1) != 1)
pdie("rb_write()");
/* use random time */
if (sleep_ms == 0) {
req.tv_sec = 0;
req.tv_nsec = 1000000L * (rand() % 50 + 1);
}
nanosleep(&req, NULL);
}
return NULL;
}
/** =========================================================================
* Thread prints current ring buffer status with "graphical" representation
* of fullness.
*
* @param rb ring buffer object
* ========================================================================== */
static void *print_rb_status(void *rb)
{
char dummy;
struct timespec req;
req.tv_sec = 0;
req.tv_nsec = 1000 * 1000L;
for (;;) {
int count = rb_count(rb);
int space = rb_space(rb);
int size = count + space;
fprintf(stderr, "%3d/%d [%.*s%.*s]\r",
count, size, count, bar, space, sbar);
/* do this until we can no longer access rb */
if (rb_recv(rb, &dummy, 1, rb_peek) == -1 && errno == ECANCELED) {
fprintf(stderr, "\n");
return NULL;
}
nanosleep(&req, NULL);
}
}
/** =========================================================================
* Run example. Start consumer and producer threads with configured action
* speed.
*
* @param cons_sleep sleep between consuming action, 0 random
* @param prod_sleep sleep between production action, 0 random
* ========================================================================== */
static void run(int cons_sleep, int prod_sleep)
{
pthread_t cons_t, prod_t, print_t;
int flags;
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
flags = rb_multithread;
if (!cons_sleep && !prod_sleep)
flags |= rb_growable;
if ((rb = rb_new(8, sizeof(int), flags)) == NULL)
pdie("rb_new()");
if (!cons_sleep && !prod_sleep) {
rb_set_hard_max_count(rb, 64);
printf("=====] growable, hard limit 64, production > consumption [=====\n");
printf("=====] consumer delay: [25-75]ms, producer delay: [50-100]ms [=====\n");
} else
printf("=====] consumer delay: %dms, producer delay: %dms [=====\n",
cons_sleep, prod_sleep);
pthread_create(&print_t, NULL, print_rb_status, rb);
printf("-----| spawning producer |-----\n");
pthread_create(&prod_t, NULL, producer, &prod_sleep);
if (prod_sleep > cons_sleep)
sleep(5);
printf("-----| spawning consumer |-----\n");
pthread_create(&cons_t, NULL, consumer, &cons_sleep);
pthread_join(cons_t, NULL);
pthread_join(prod_t, NULL);
rb_stop(rb);
pthread_join(print_t, NULL);
rb_destroy(rb);
}
/* ==========================================================================
* ░█▄█░█▀█░▀█▀░█▀█
* ░█░█░█▀█░░█░░█░█
* ░▀░▀░▀░▀░▀▀▀░▀░▀
* ========================================================================== */
int main(void)
{
run(100, 500);
run(500, 100);
run(0, 0);
return 0;
}
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