[LTP] [PATCH 2/2 v2] fork08: Rewrite the test to a proper synchronization
Xie Ziyao
xieziyao@huawei.com
Mon Jul 5 09:59:03 CEST 2021
Rewrite fork08 to a proper synchronization with the new API.
Fixes: #774
Signed-off-by: Xie Ziyao <xieziyao@huawei.com>
---
v1->v2:
1. Write a new test as follows,
* Parent writes 1 bytes (for example 'a') to a file in setup()
* Parent opens a file descriptor for reading pointing to that file
* Parent forks a child to close fd
* Parent forks another child to read a byte from the file checks that the byte is 'a' then exits
* Parent waits the all the children
* Parent checks that the end of file is reached
2. Use file descriptors instead of the FILE.
testcases/kernel/syscalls/fork/fork08.c | 200 ++++++------------------
1 file changed, 49 insertions(+), 151 deletions(-)
diff --git a/testcases/kernel/syscalls/fork/fork08.c b/testcases/kernel/syscalls/fork/fork08.c
index 1123f7473..9e30ffe3d 100644
--- a/testcases/kernel/syscalls/fork/fork08.c
+++ b/testcases/kernel/syscalls/fork/fork08.c
@@ -1,172 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
- * Copyright (c) International Business Machines Corp., 2001
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
- * the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * NAME
- * fork08.c
- *
- * DESCRIPTION
- * Check if the parent's file descriptors are affected by
- * actions in the child; they should not be.
- *
- * ALGORITHM
- * Parent opens a file.
- * Forks a child which closes a file.
- * Parent forks a second child which attempts to read the (closed)
- * file.
- *
- * USAGE
- * fork08
- *
- * HISTORY
- * 07/2001 Ported by Wayne Boyer
+ * Copyright (c) International Business Machines Corp., 2001
+ * 07/2001 Ported by Wayne Boyer
+ * Copyright (c) 2021 Xie Ziyao <xieziyao@huawei.com>
+ */
+
+/*\
+ * [Description]
*
- * RESTRICTIONS
- * None
+ * Check that the parent's file descriptors will not be affected by actions
+ * in the child.
*/
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <stdio.h>
-#include "test.h"
+#include <stdlib.h>
-char *TCID = "fork08";
-int TST_TOTAL = 1;
+#include "tst_test.h"
-static void setup(void);
-static void cleanup(void);
+#define TESTFILE "testfile_fork08"
-static char pbuf[10];
-static char fnamebuf[40];
+static int fd;
+static char buf;
-int main(int ac, char **av)
+static void run(void)
{
- int status, count, forks, pid1;
- int ch_r_stat;
- FILE *rea, *writ;
-
- int lc;
-
- tst_parse_opts(ac, av, NULL, NULL);
-
- setup();
-
- for (lc = 0; TEST_LOOPING(lc); lc++) {
- tst_count = 0;
+ int ret;
- writ = fopen(fnamebuf, "w");
- if (writ == NULL)
- tst_resm(TFAIL, "failed to fopen file for write");
- rea = fopen(fnamebuf, "r");
- if (rea == NULL)
- tst_resm(TFAIL, "failed to fopen file for read");
-
- fprintf(writ, "abcdefghijklmnopqrstuv");
- fflush(writ);
- sleep(1);
-
- if ((getc(rea)) != 'a')
- tst_resm(TFAIL, "getc from read side was confused");
-
- forks = 0;
-
-forkone:
- ++forks;
-
- pid1 = fork();
- if (pid1 != 0) {
- tst_resm(TINFO, "parent forksval: %d", forks);
-
- if ((pid1 != (-1)) && (forks < 2))
- goto forkone;
- else if (pid1 < 0)
- tst_resm(TINFO, "Fork failed");
- } else { /* child */
- /*
- * If first child close the file descriptor for the
- * read stream
- */
- if (forks == 1) {
- if ((fclose(rea)) == -1) {
- tst_resm(TFAIL, "error in first child"
- " closing fildes");
- }
- _exit(0);
- }
-
- /*
- * If second child attempt to read from the file
- */
- else if (forks == 2) {
- ch_r_stat = getc(rea);
- tst_resm(TINFO, "second child got char: %c",
- ch_r_stat);
- if (ch_r_stat == 'b') {
- tst_resm(TPASS, "Test passed in child "
- "number %d", forks);
- exit(0);
- } else if (ch_r_stat == EOF) {
- tst_resm(TFAIL, "Second child got "
- "EOF");
- exit(-1);
- } else {
- tst_resm(TFAIL, "test failed in child "
- "no %d", forks);
- exit(-1);
- }
- } else { /* end of second child */
- tst_resm(TINFO, "forksnumber: %d", forks);
- exit(3);
- }
- }
-
- for (count = 0; count <= forks; count++) {
- wait(&status);
- tst_resm(TINFO, "exit status of wait "
- " expected 0 got %d", status);
- status >>= 8;
- if (status == 0)
- tst_resm(TPASS, "parent test PASSED");
- else
- tst_resm(TFAIL, "parent test FAILED");
- }
-
- tst_resm(TINFO, "Number of processes forked is %d", forks);
- fclose(rea);
- fclose(writ);
+ fd = SAFE_OPEN(TESTFILE, O_RDONLY);
+ if (!SAFE_FORK()) {
+ SAFE_CLOSE(fd);
+ exit(0);
+ }
+ tst_reap_children();
+
+ if (!SAFE_FORK()) {
+ SAFE_READ(1, fd, &buf, 1);
+ if (buf != 'a')
+ tst_res(TFAIL, "%6d: read '%c' instead of 'a'",
+ getpid(), buf);
+ exit(0);
}
+ tst_reap_children();
- cleanup();
- tst_exit();
+ ret = read(fd, &buf, 1);
+ if (ret == 0)
+ tst_res(TPASS, "read the end of file correctly");
+ else
+ tst_res(TFAIL, "read() returns %d, expected 0", ret);
+
+ SAFE_CLOSE(fd);
}
static void setup(void)
{
- tst_sig(FORK, DEF_HANDLER, cleanup);
- umask(0);
- TEST_PAUSE;
- tst_tmpdir();
-
- strcpy(fnamebuf, "fork07.");
- sprintf(pbuf, "%d", getpid());
- strcat(fnamebuf, pbuf);
+ tst_fill_file(TESTFILE, 'a', 1, 1);
}
static void cleanup(void)
{
- tst_rmdir();
+ if (fd > 0)
+ SAFE_CLOSE(fd);
}
+
+static struct tst_test test = {
+ .forks_child = 1,
+ .needs_tmpdir = 1,
+ .cleanup = cleanup,
+ .setup = setup,
+ .test_all = run,
+};
--
2.17.1
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