android13/external/ltp/testcases/kernel/syscalls/truncate/truncate02.c

115 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) International Business Machines Corp., 2001
* 07/2001 John George
*/
/*\
* [Description]
*
* Verify that:
*
* - truncate(2) truncates a file to a specified length successfully.
* - If the file is larger than the specified length, the extra data is lost.
* - If the file is shorter than the specified length, the extra data is filled by '0'.
* - truncate(2) doesn't change offset.
*/
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include "tst_test.h"
#include "tst_safe_prw.h"
#define TESTFILE "testfile"
#define FILE_SIZE 1024
#define TRUNC_LEN1 256
#define TRUNC_LEN2 512
static int fd;
static struct tcase {
off_t trunc_len;
off_t read_off;
off_t read_count;
char exp_char;
} tcases[] = {
{TRUNC_LEN1, 0, TRUNC_LEN1, 'a'},
{TRUNC_LEN2, TRUNC_LEN1, TRUNC_LEN1, '\0'},
};
static void verify_truncate(unsigned int n)
{
struct tcase *tc = &tcases[n];
struct stat stat_buf;
char read_buf[tc->read_count];
int i;
memset(read_buf, 'b', tc->read_count);
TEST(truncate(TESTFILE, tc->trunc_len));
if (TST_RET == -1) {
tst_res(TFAIL | TTERRNO, "truncate(%s, %ld) failed",
TESTFILE, tc->trunc_len);
return;
}
if (TST_RET != 0) {
tst_res(TFAIL | TTERRNO,
"truncate(%s, %ld) returned invalid value %ld",
TESTFILE, tc->trunc_len, TST_RET);
return;
}
SAFE_STAT(TESTFILE, &stat_buf);
if (stat_buf.st_size != tc->trunc_len) {
tst_res(TFAIL, "%s: Incorrect file size %ld, expected %ld",
TESTFILE, stat_buf.st_size, tc->trunc_len);
return;
}
if (SAFE_LSEEK(fd, 0, SEEK_CUR)) {
tst_res(TFAIL, "truncate(%s, %ld) changes offset",
TESTFILE, tc->trunc_len);
return;
}
SAFE_PREAD(1, fd, read_buf, tc->read_count, tc->read_off);
for (i = 0; i < tc->read_count; i++) {
if (read_buf[i] != tc->exp_char) {
tst_res(TFAIL, "%s: wrong content %c, expected %c",
TESTFILE, read_buf[i], tc->exp_char);
return;
}
}
tst_res(TPASS, "truncate(%s, %ld) succeeded",
TESTFILE, tc->trunc_len);
}
static void setup(void)
{
fd = SAFE_OPEN(TESTFILE, O_RDWR | O_CREAT, 0644);
tst_fill_fd(fd, 'a', FILE_SIZE, 1);
SAFE_LSEEK(fd, 0, SEEK_SET);
}
static void cleanup(void)
{
if (fd > 0)
SAFE_CLOSE(fd);
}
static struct tst_test test = {
.needs_tmpdir = 1,
.setup = setup,
.cleanup = cleanup,
.tcnt = ARRAY_SIZE(tcases),
.test = verify_truncate,
};