Generalize process spawning so its test compiles (but fails) in Windows

- pid, stdout/stderr_pipe now encapsulated in process_handle
- read_all replaced by tor_read_all_from_process_stdin/stderr
- waitpid replaced by tor_get_exit_code

Untested on *nix
This commit is contained in:
Steven Murdoch 2011-07-21 16:34:48 +01:00
parent 2002d4acdf
commit 35c89be02b
3 changed files with 101 additions and 33 deletions

View File

@ -2978,14 +2978,15 @@ format_helper_exit_status(unsigned char child_state, int saved_errno,
* -1. Some parts of this code are based on the POSIX subprocess module from
* Python.
*/
int
tor_spawn_background(const char *const filename, int *stdout_read,
int *stderr_read, const char **argv)
process_handle_t
tor_spawn_background(const char *const filename, const char **argv)
{
process_handle_t process_handle;
#ifdef MS_WINDOWS
(void) filename; (void) stdout_read; (void) stderr_read; (void) argv;
(void) filename; (void) argv;
log_warn(LD_BUG, "not yet implemented on Windows.");
return -1;
process_handle.status = -1;
return process_handle;
#else
pid_t pid;
int stdout_pipe[2];
@ -3016,7 +3017,8 @@ tor_spawn_background(const char *const filename, int *stdout_read,
log_warn(LD_GENERAL,
"Failed to set up pipe for stdout communication with child process: %s",
strerror(errno));
return -1;
process_handle.status = -1;
return process_handle;
}
retval = pipe(stderr_pipe);
@ -3024,7 +3026,8 @@ tor_spawn_background(const char *const filename, int *stdout_read,
log_warn(LD_GENERAL,
"Failed to set up pipe for stderr communication with child process: %s",
strerror(errno));
return -1;
process_handle.status = -1;
return process_handle;
}
child_state = CHILD_STATE_MAXFD;
@ -3109,7 +3112,8 @@ tor_spawn_background(const char *const filename, int *stdout_read,
(void) nbytes;
_exit(255);
return -1; /* Never reached, but avoids compiler warning */
process_handle.status = -1;
return process_handle; /* Never reached, but avoids compiler warning */
}
/* In parent */
@ -3120,11 +3124,12 @@ tor_spawn_background(const char *const filename, int *stdout_read,
close(stdout_pipe[1]);
close(stderr_pipe[0]);
close(stderr_pipe[1]);
return -1;
process_handle.status = -1;
return process_handle;
}
/* Return read end of the pipes to caller, and close write end */
*stdout_read = stdout_pipe[0];
process_handle.stdout_pipe = stdout_pipe[0];
retval = close(stdout_pipe[1]);
if (-1 == retval) {
@ -3135,7 +3140,7 @@ tor_spawn_background(const char *const filename, int *stdout_read,
needs to know about the pid in order to reap it later */
}
*stderr_read = stderr_pipe[0];
process_handle.stderr_pipe = stderr_pipe[0];
retval = close(stderr_pipe[1]);
if (-1 == retval) {
@ -3146,7 +3151,56 @@ tor_spawn_background(const char *const filename, int *stdout_read,
needs to know about the pid in order to reap it later */
}
return pid;
process_handle.status = 0;
process_handle.pid = pid;
return process_handle;
#endif
}
int
tor_get_exit_code(const process_handle_t process_handle)
{
#ifdef MS_WINDOWS
log_warn(LD_BUG, "not yet implemented on Windows.");
return -1;
#else
int stat_loc;
retval = waitpid(process_handle.pid, &stat_loc, 0);
if (retval != process_handle.pid) {
log_warn(LD_GENERAL, "waitpid() failed for PID %d: %s", process_handle.pid,
sterror(errno));
return -1;
}
if (!WIFEXITED(stat_loc)) {
log_warn(LD_GENERAL, "Process %d did not exit normally", process_handle.pid);
return -1;
}
return WEXITSTATUS(stat_loc);
#endif // MS_WINDOWS
}
ssize_t
tor_read_all_from_process_stdin(const process_handle_t process_handle,
char *buf, size_t count)
{
#ifdef MS_WINDOWS
return -1;
#else
return read_all(process_handle.stdin_pipe, buf, count, 0);
#endif
}
ssize_t
tor_read_all_from_process_stderr(const process_handle_t process_handle,
char *buf, size_t count)
{
#ifdef MS_WINDOWS
return -1;
#else
return read_all(process_handle.stderr_pipe, buf, count, 0);
#endif
}

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@ -347,8 +347,27 @@ HANDLE load_windows_system_library(const TCHAR *library_name);
#ifdef UTIL_PRIVATE
/* Prototypes for private functions only used by util.c (and unit tests) */
int tor_spawn_background(const char *const filename, int *stdout_read,
int *stderr_read, const char **argv);
typedef struct process_handle_s {
int status;
#ifdef MS_WINDOWS
HANDLE stdout_pipe;
HANDLE stderr_pipe;
HANDLE pid;
#else
int stdout_pipe;
int stderr_pipe;
int pid;
#endif // MS_WINDOWS
} process_handle_t;
process_handle_t tor_spawn_background(const char *const filename,
const char **argv);
int tor_get_exit_code(const process_handle_t pid);
ssize_t tor_read_all_from_process_stdin(const process_handle_t process_handle,
char *buf, size_t count);
ssize_t tor_read_all_from_process_stderr(const process_handle_t process_handle,
char *buf, size_t count);
void format_helper_exit_status(unsigned char child_state,
int saved_errno, char *hex_errno);

View File

@ -1376,42 +1376,38 @@ test_util_fgets_eagain(void *ptr)
}
#endif
#ifndef MS_WINDOWS
/** Helper function for testing tor_spawn_background */
static void
run_util_spawn_background(const char *argv[], const char *expected_out,
const char *expected_err, int expected_exit)
{
int stdout_pipe=-1, stderr_pipe=-1;
int retval, stat_loc;
pid_t pid;
int retval;
ssize_t pos;
process_handle_t process_handle;
char stdout_buf[100], stderr_buf[100];
/* Start the program */
retval = tor_spawn_background(argv[0], &stdout_pipe, &stderr_pipe, argv);
tt_int_op(retval, >, 0);
tt_int_op(stdout_pipe, >, 0);
tt_int_op(stderr_pipe, >, 0);
pid = retval;
process_handle = tor_spawn_background(argv[0], argv);
tt_int_op(process_handle.status, ==, 0);
tt_int_op(process_handle.stdout_pipe, >, 0);
tt_int_op(process_handle.stderr_pipe, >, 0);
/* Check stdout */
pos = read_all(stdout_pipe, stdout_buf, sizeof(stdout_buf) - 1, 0);
pos = tor_read_all_from_process_stdin(process_handle, stdout_buf,
sizeof(stdout_buf) - 1);
tt_assert(pos >= 0);
stdout_buf[pos] = '\0';
tt_int_op(pos, ==, strlen(expected_out));
tt_str_op(stdout_buf, ==, expected_out);
/* Check it terminated correctly */
retval = waitpid(pid, &stat_loc, 0);
tt_int_op(retval, ==, pid);
tt_assert(WIFEXITED(stat_loc));
tt_int_op(WEXITSTATUS(stat_loc), ==, expected_exit);
tt_assert(!WIFSIGNALED(stat_loc));
tt_assert(!WIFSTOPPED(stat_loc));
retval = tor_get_exit_code(process_handle);
tt_int_op(retval, ==, expected_exit);
/* Check stderr */
pos = read_all(stderr_pipe, stderr_buf, sizeof(stderr_buf) - 1, 0);
pos = tor_read_all_from_process_stderr(process_handle, stderr_buf,
sizeof(stderr_buf) - 1);
tt_assert(pos >= 0);
stderr_buf[pos] = '\0';
tt_int_op(pos, ==, strlen(expected_err));
@ -1447,7 +1443,6 @@ test_util_spawn_background_fail(void *ptr)
run_util_spawn_background(argv, expected_out, expected_err, 255);
}
#endif
static void
test_util_di_ops(void)
@ -1533,9 +1528,9 @@ struct testcase_t util_tests[] = {
UTIL_TEST(exit_status, 0),
#ifndef MS_WINDOWS
UTIL_TEST(fgets_eagain, TT_SKIP),
#endif
UTIL_TEST(spawn_background_ok, 0),
UTIL_TEST(spawn_background_fail, 0),
#endif
END_OF_TESTCASES
};