posix_spawn: If an error is detected in the child process, reap the zombie.

Formerly, in this case an error was returned but the pid was also returned
to the application, requiring the application to use unspecified behaviour
(the returned pid in error situations) to avoid zombies.

Now, reap the zombie and do not return the pid.

MFC after:	2 weeks

2 files changed, 91 insertions, 1 deletions

diff --git a/tools/regression/lib/libc/gen/Makefile b/tools/regression/lib/libc/gen/Makefile
index a79dc2f..72a0750 100644
--- a/tools/regression/lib/libc/gen/Makefile
+++ b/tools/regression/lib/libc/gen/Makefile
@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-TESTS=	test-fmtcheck test-fnmatch test-fpclassify test-wordexp
+TESTS=	test-fmtcheck test-fnmatch test-fpclassify test-posix_spawn test-wordexp
 
 .PHONY: tests
 tests: ${TESTS}
diff --git a/tools/regression/lib/libc/gen/test-posix_spawn.c b/tools/regression/lib/libc/gen/test-posix_spawn.c
new file mode 100644
index 0000000..f1b8d43
--- /dev/null
+++ b/tools/regression/lib/libc/gen/test-posix_spawn.c
@@ -0,0 +1,90 @@
+/*-
+ * Copyright (c) 2011 Jilles Tjoelker
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Test program for posix_spawn() and posix_spawnp() as specified by
+ * IEEE Std. 1003.1-2008.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/wait.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <spawn.h>
+
+int
+main(int argc, char *argv[])
+{
+	int error, status;
+	pid_t pid, waitres;
+	char *myargs[4];
+	char *myenv[2] = { "answer=42", NULL };
+
+	/* Make sure we have no child processes. */
+	while (waitpid(-1, NULL, 0) != -1)
+		;
+	assert(errno == ECHILD);
+
+	/* Simple test. */
+	myargs[0] = "sh";
+	myargs[1] = "-c";
+	myargs[2] = "exit $answer";
+	myargs[3] = NULL;
+	error = posix_spawnp(&pid, myargs[0], NULL, NULL, myargs, myenv);
+	assert(error == 0);
+	waitres = waitpid(pid, &status, 0);
+	assert(waitres == pid);
+	assert(WIFEXITED(status) && WEXITSTATUS(status) == 42);
+
+	/*
+	 * If the executable does not exist, the function shall either fail
+	 * and not create a child process or succeed and create a child
+	 * process that exits with status 127.
+	 */
+	myargs[0] = "/var/empty/nonexistent";
+	myargs[1] = NULL;
+	error = posix_spawn(&pid, myargs[0], NULL, NULL, myargs, myenv);
+	if (error == 0) {
+		waitres = waitpid(pid, &status, 0);
+		assert(waitres == pid);
+		assert(WIFEXITED(status) && WEXITSTATUS(status) == 127);
+	} else {
+		assert(error == ENOENT);
+		waitres = waitpid(-1, NULL, 0);
+		assert(waitres == -1 && errno == ECHILD);
+	}
+
+	printf("PASS posix_spawn()\n");
+	printf("PASS posix_spawnp()\n");
+
+	return (0);
+}