Test case for mdb_env_copyfd2 deadlock

copyfd2-deadlock.c

/*
 * Copyright 2012 Howard Chu, Symas Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted only as authorized by the OpenLDAP
 * Public License.
 *
 * A copy of this license is available in the file LICENSE in the
 * top-level directory of the distribution or, alternatively, at
 * <http://www.OpenLDAP.org/license.html>.
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <errno.h>
#include <signal.h>
#include "lmdb.h"

struct copyinfo {
	MDB_env *env;
	int fd;
};

static void *
copythr(void *arg)
{
	struct copyinfo *ci = (struct copyinfo*)arg;
	MDB_env *env = (MDB_env*)arg;
	int rc;

	rc = mdb_env_copyfd2(ci->env, ci->fd, MDB_CP_COMPACT);
	return (void*)rc;
}

int main(int argc,char * argv[])
{
	int rc, copy_rc;
	MDB_env *env;
	int pipefd[2];
	sigset_t set;
	pthread_t pid;
	struct copyinfo ci;

#define check(rc, x) rc = x; if (rc) { fprintf(stderr, #x ": (%d) %s\n", rc, mdb_strerror(rc)); goto leave; }

	sigemptyset(&set);
	sigaddset(&set, SIGPIPE);
	rc = pthread_sigmask(SIG_BLOCK, &set, NULL);
	if (rc) {
		return 1;
	}

	if (pipe(pipefd) != 0) {
		return errno;
	}

	check(rc, mdb_env_create(&env));
	check(rc, mdb_env_open(env, "./", 0, 0664));

	ci.env = env;
	ci.fd = pipefd[1];

	rc = pthread_create(&pid, NULL, &copythr, &ci);
	if (rc) {
		goto leave;
	}

	close(pipefd[0]);

	rc = pthread_join(pid, &copy_rc);
	if (rc) {
		goto leave;
	}

	if (copy_rc != EPIPE) {
		fprintf(stderr, "mdb_env_copyfd2 did not return EPIPE but %d\n", copy_rc);
		rc = 1;
	} else {
		fprintf(stderr, "mdb_env_copyfd2 returned EPIPE\n");
		rc = 0;
	}

leave:
	mdb_env_close(env);
	return rc;
#undef check
}

Compile using

gcc -o copy -g -pthread copyfd2-deadlock.c -llmdb