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/*
* Copyright (c) 2022 Firebuild Inc.
* All rights reserved.
*
* Free for personal use and commercial trial.
* Non-trial commercial use requires licenses available from https://firebuild.com.
* Modification and redistribution are permitted, but commercial use of derivative
* works is subject to the same requirements of this license
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#define TOSTR(x) TOSTR2(x)
#define TOSTR2(x) #x
#define LOC "[" __FILE__ ":" TOSTR(__LINE__) "]"
int main() {
int fd;
/* Open existing file for reading. */
fd = open("/etc/passwd", O_RDONLY);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
/* Attempt to open nonexisting file for reading. */
fd = open("/no/such/file", O_RDONLY);
if (fd != -1) {
fprintf(stderr, "open" LOC " should have failed\n");
exit(1);
}
/* Attempt to write to nonexisting file, without O_CREAT. */
fd = open("wont_create_1", O_WRONLY|O_TRUNC);
if (fd != -1) {
fprintf(stderr, "open" LOC " should have failed\n");
exit(1);
}
/* Attempt to write to existing file, with O_EXCL. */
fd = open("test_empty_1.txt", O_WRONLY|O_CREAT|O_EXCL, 0600);
if (fd != -1) {
fprintf(stderr, "open" LOC " should have failed\n");
exit(1);
}
/* Open for writing, but don't modify. */
fd = open("test_nonempty_1.txt", O_WRONLY);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
/* Open for writing, truncate. */
fd = open("test_nonempty_2.txt", O_WRONLY|O_TRUNC);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
/* Open for writing existing file, with CREAT and TRUNC. */
fd = creat("test_maybe_exists_1.txt", 0600);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
/* Open for writing nonexisting file, with CREAT and TRUNC. */
fd = creat("test_maybe_exists_2.txt", 0600);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
/* Exclusive creation. */
fd = open("test_exclusive.txt", O_WRONLY|O_CREAT|O_EXCL, 0600);
if (fd == -1) {
perror("open" LOC);
exit(1);
}
close(fd);
return 0;
}
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