Attachment 871086 Details for Bug 1217688

c reproducer, incl. fork()

db.c (text/plain), 3.00 KB, created by Jiri Slaby on 2023-11-30 12:46:06 UTC

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Creator: Jiri Slaby

Created: 2023-11-30 12:46:06 UTC

Size: 3.00 KB

patch

obsolete

>#include <err.h>
>#include <stdio.h>
>#include <stdlib.h>
>#include <string.h>
>#include <unistd.h>
>
>#include <sys/wait.h>
>
>#include <mysql.h>
>#include <mysql/mysqld_error.h>
>
>int begin(MYSQL *sql)
>{
>#if 1
>	if (mysql_query(sql, "START TRANSACTION;")) {
>		warnx("db START failed: %s", mysql_error(sql));
>		return -1;
>	}
>#else
>	if (mysql_query(&mysql, "LOCK TABLES sources WRITE, structs WRITE, members WRITE, uses WRITE;")) {
>		warnx("db LOCK failed: ", mysql_error(&mysql) << "\n";
>		return -1;
>	}
>#endif
>	return 0;
>}
>
>int end(MYSQL *sql)
>{
>#if 1
>	if (mysql_commit(sql)) {
>		warnx("db commit failed: %s", mysql_error(sql));
>		return -1;
>	}
>#else
>	if (mysql_query(&mysql, "UNLOCK TABLES;")) {
>		warnx("db UNLOCK failed: ", mysql_error(&mysql) << "\n";
>		return -1;
>	}
>#endif
>	return 0;
>}
>
>static int connect(MYSQL *mysql)
>{
>	if (!mysql_init(mysql)) {
>		warnx("mysql_init\n");
>		return -1;
>	}
>
>	if (!mysql_real_connect(mysql, "127.0.0.1", "xslaby", NULL, "structs_66", 0, NULL, 0)) {
>		warnx("mysql_real_connect: %s", mysql_error(mysql));
>		goto fail;
>	}
>
>	return 0;
>fail:
>	mysql_close(mysql);
>	return -1;
>}
>
> __attribute__((noreturn)) void child()
>{
>	MYSQL mysql;
>
>	if (connect(&mysql))
>		exit(1);
>
>	if (mysql_autocommit(&mysql, 0)) {
>		warnx("mysql_autocommit: %s", mysql_error(&mysql));
>		goto fail;
>	}
>
>	MYSQL_STMT *insSrc = mysql_stmt_init(&mysql);
>	if (!insSrc) {
>		warnx("db stmt_init failed: %s", mysql_error(&mysql));
>		goto fail;
>	}
>
>	const char create[] = "INSERT IGNORE INTO sources(src) VALUES (?)";
>	if (mysql_stmt_prepare(insSrc, create, strlen(create))) {
>		warnx("db prep failed for: %s: %s", create, mysql_error(&mysql));
>		goto fail;
>	}
>
>	pid_t pid = getpid();
>
>	if (begin(&mysql) < 0)
>		exit(1);
>
>	for (unsigned a = 0; a < 50; a++) {
>		char src[24];
>		unsigned long len = snprintf(src, sizeof(src), "src-%.6u-%.5u", pid, a);
>
>		MYSQL_BIND b = {
>			.length = &len,
>			.buffer = src,
>			.buffer_length = sizeof(src),
>			.buffer_type = MYSQL_TYPE_STRING,
>		};
>
>		if (mysql_stmt_bind_param(insSrc, &b)) {
>			warnx("db bind failed: %s", mysql_stmt_error(insSrc));
>			exit(1);
>		}
>
>		while (mysql_stmt_execute(insSrc)) {
>			switch (mysql_stmt_errno(insSrc)) {
>			case ER_LOCK_DEADLOCK:
>			case ER_LOCK_WAIT_TIMEOUT:
>				usleep(1000);
>				continue;
>			}
>
>			warnx("[%u] db exec failed: %s", pid, mysql_stmt_error(insSrc));
>			goto fail_stmt;
>		}
>
>		if (mysql_stmt_affected_rows(insSrc) != 1)
>			warnx("%s: %llu", src, mysql_stmt_affected_rows(insSrc));
>	}
>
>	if (end(&mysql) < 0)
>		exit(1);
>
>fail_stmt:
>	mysql_stmt_close(insSrc);
>fail:
>	mysql_close(&mysql);
>	exit(0);
>}
>
>#define CHILDREN 10
>
>int main()
>{
>	MYSQL mysql;
>
>	if (connect(&mysql))
>		return EXIT_FAILURE;
>
>	if (mysql_query(&mysql, "DELETE FROM sources;")) {
>		warnx("cannot DELETE: %s", mysql_error(&mysql));
>		mysql_close(&mysql);
>		return EXIT_FAILURE;
>	}
>
>	mysql_close(&mysql);
>
>	for (unsigned i = 0; i < CHILDREN; i++) {
>		switch (fork()) {
>		case -1:
>			i = CHILDREN;
>			break;
>		case 0:
>			child();
>		default:
>			break;
>		}
>	}
>
>	for (unsigned i = 0; i < CHILDREN; i++)
>		wait(NULL);
>
>	return 0;
>}

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Attachments on bug 1217688: 871082 | 871086 | 871087