static int write_string_file_atomic(const char *fn, const char *line, bool enforce_newline) {
_cleanup_fclose_ FILE *f = NULL;
_cleanup_free_ char *p = NULL;
int r;
assert(fn);
assert(line);
r = fopen_temporary(fn, &f, &p);
if (r < 0)
return r;
(void) fchmod_umask(fileno(f), 0644);
r = write_string_stream(f, line, enforce_newline);
if (r >= 0) {
if (rename(p, fn) < 0)
r = -errno;
}
if (r < 0)
(void) unlink(p);
return r;
}
int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags) {
_cleanup_fclose_ FILE *f = NULL;
assert(fn);
assert(line);
if (flags & WRITE_STRING_FILE_ATOMIC) {
assert(flags & WRITE_STRING_FILE_CREATE);
return write_string_file_atomic(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
}
if (flags & WRITE_STRING_FILE_CREATE) {
f = fopen(fn, "we");
if (!f)
return -errno;
} else {
int fd;
/* We manually build our own version of fopen(..., "we") that
* works without O_CREAT */
fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return -errno;
f = fdopen(fd, "we");
if (!f) {
safe_close(fd);
return -errno;
}
}
return write_string_stream(f, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
}
int write_string_file(const char *fn, const char *line) {
_cleanup_fclose_ FILE *f = NULL;
assert(fn);
assert(line);
f = fopen(fn, "we");
if (!f)
return -errno;
return write_string_stream(f, line);
}
static void test_clock_is_localtime(void) {
char adjtime[] = "/tmp/test-adjtime.XXXXXX";
int fd = -1;
_cleanup_fclose_ FILE* f = NULL;
static const struct scenario {
const char* contents;
int expected_result;
} scenarios[] = {
/* adjtime configures UTC */
{"0.0 0 0\n0\nUTC\n", 0},
/* adjtime configures local time */
{"0.0 0 0\n0\nLOCAL\n", 1},
/* no final EOL */
{"0.0 0 0\n0\nUTC", 0},
{"0.0 0 0\n0\nLOCAL", 1},
/* empty value -> defaults to UTC */
{"0.0 0 0\n0\n", 0},
/* unknown value -> defaults to UTC */
{"0.0 0 0\n0\nFOO\n", 0},
/* no third line */
{"0.0 0 0", 0},
{"0.0 0 0\n", 0},
{"0.0 0 0\n0", 0},
};
/* without an adjtime file we default to UTC */
assert_se(clock_is_localtime("/nonexisting/adjtime") == 0);
fd = mkostemp_safe(adjtime);
assert_se(fd >= 0);
log_info("adjtime test file: %s", adjtime);
f = fdopen(fd, "w");
assert_se(f);
for (size_t i = 0; i < ELEMENTSOF(scenarios); ++i) {
log_info("scenario #%zu:, expected result %i", i, scenarios[i].expected_result);
log_info("%s", scenarios[i].contents);
rewind(f);
ftruncate(fd, 0);
assert_se(write_string_stream(f, scenarios[i].contents, WRITE_STRING_FILE_AVOID_NEWLINE) == 0);
assert_se(clock_is_localtime(adjtime) == scenarios[i].expected_result);
}
unlink(adjtime);
}
int write_string_file_no_create(const char *fn, const char *line) {
_cleanup_fclose_ FILE *f = NULL;
int fd;
assert(fn);
assert(line);
/* We manually build our own version of fopen(..., "we") that
* without O_CREAT */
fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return -errno;
f = fdopen(fd, "we");
if (!f) {
safe_close(fd);
return -errno;
}
return write_string_stream(f, line);
}
int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags) {
_cleanup_fclose_ FILE *f = NULL;
int q, r;
assert(fn);
assert(line);
if (flags & WRITE_STRING_FILE_ATOMIC) {
assert(flags & WRITE_STRING_FILE_CREATE);
r = write_string_file_atomic(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
if (r < 0)
goto fail;
return r;
}
if (flags & WRITE_STRING_FILE_CREATE) {
f = fopen(fn, "we");
if (!f) {
r = -errno;
goto fail;
}
} else {
int fd;
/* We manually build our own version of fopen(..., "we") that
* works without O_CREAT */
fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0) {
r = -errno;
goto fail;
}
f = fdopen(fd, "we");
if (!f) {
r = -errno;
safe_close(fd);
goto fail;
}
}
r = write_string_stream(f, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
if (r < 0)
goto fail;
return 0;
fail:
if (!(flags & WRITE_STRING_FILE_VERIFY_ON_FAILURE))
return r;
f = safe_fclose(f);
/* OK, the operation failed, but let's see if the right
* contents in place already. If so, eat up the error. */
q = verify_file(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE));
if (q <= 0)
return r;
return 0;
}
