android13/external/ltp/testcases/kernel/syscalls/pipe/pipe12.c

114 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2020 FUJITSU LIMITED. All rights reserved.
* Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
*
* Test Description:
* A pipe has a limited capacity. If the pipe with non block mode is full,
* then a write(2) will fail and get EAGAIN error. Otherwise, from 1 to
* PIPE_BUF bytes may be written.
*/
#define _GNU_SOURCE
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include "tst_test.h"
#include "lapi/fcntl.h"
static int fds[2];
static char *wrbuf;
static char *rdbuf;
static ssize_t max_size, invalid_size;
static struct tcase {
int full_flag;
int offset;
char *message;
int check_flag;
} tcases[] = {
{1, 0, "Write to full pipe", 1},
/*
* For a non-empty(unaligned page size) pipe, the sequent large size
* write(>page_size)will use new pages. So it may exist a hole in
* page and we print this value instead of checking it.
*/
{0, 1, "Write to non-empty pipe", 0},
{0, 0, "Write to empty pipe", 1},
};
static void verify_pipe(unsigned int n)
{
struct tcase *tc = &tcases[n];
int nbytes;
memset(rdbuf, 0, max_size);
tst_res(TINFO, "%s", tc->message);
if (tc->full_flag) {
SAFE_WRITE(1, fds[1], wrbuf, max_size);
TEST(write(fds[1], "x", 1));
if (TST_RET != -1) {
tst_res(TFAIL, "write succeeded unexpectedly");
goto clean_pipe_buf;
}
if (TST_ERR == EAGAIN)
tst_res(TPASS | TTERRNO, "write failed as expected");
else
tst_res(TFAIL | TTERRNO, "write failed, expected EAGAIN but got");
} else {
SAFE_WRITE(1, fds[1], "x", tc->offset);
TEST(write(fds[1], wrbuf, invalid_size));
if (TST_RET == -1) {
tst_res(TFAIL, "write failed unexpectedly");
goto clean_pipe_buf;
}
tst_res(TPASS, "write succeeded as expectedly");
}
SAFE_IOCTL(fds[1], FIONREAD, &nbytes);
if (tc->check_flag) {
if (nbytes == max_size - tc->offset)
tst_res(TPASS, "write %d bytes", nbytes);
else
tst_res(TFAIL, "write expected %ld bytes, got %d bytes",
max_size, nbytes);
} else
tst_res(TPASS, "write %d bytes", nbytes);
clean_pipe_buf:
SAFE_READ(0, fds[0], rdbuf, max_size);
}
static void cleanup(void)
{
if (fds[0] > 0)
SAFE_CLOSE(fds[0]);
if (fds[1] > 0)
SAFE_CLOSE(fds[1]);
if (wrbuf)
free(wrbuf);
if (rdbuf)
free(rdbuf);
}
static void setup(void)
{
SAFE_PIPE(fds);
max_size = SAFE_FCNTL(fds[1], F_GETPIPE_SZ);
invalid_size = max_size + 4096;
wrbuf = SAFE_MALLOC(invalid_size);
rdbuf = SAFE_MALLOC(max_size);
memset(wrbuf, 'x', invalid_size);
SAFE_FCNTL(fds[1], F_SETFL, O_NONBLOCK);
SAFE_FCNTL(fds[0], F_SETFL, O_NONBLOCK);
}
static struct tst_test test = {
.test = verify_pipe,
.setup = setup,
.cleanup = cleanup,
.tcnt = ARRAY_SIZE(tcases),
};