HelenOS sources
This source file includes following definitions.
- usage
- reopen
- spawn
- main
#include <stdlib.h>
#include <str.h>
#include <stdio.h>
#include <task.h>
#include <str_error.h>
#include <errno.h>
#include <vfs/vfs.h>
#define NAME "redir"
static void usage(void)
{
fprintf(stderr, "Usage: %s [-i <stdin>] [-o <stdout>] [-e <stderr>] -- <cmd> [args ...]\n",
NAME);
}
static void reopen(FILE **stream, int fd, const char *path, int flags, int mode,
const char *fmode)
{
if (fclose(*stream))
return;
*stream = NULL;
int oldfd;
errno_t rc = vfs_lookup_open(path, WALK_REGULAR | flags, mode, &oldfd);
if (rc != EOK)
return;
if (oldfd != fd) {
int newfd;
if (vfs_clone(oldfd, fd, false, &newfd) != EOK)
return;
assert(newfd == fd);
if (vfs_put(oldfd))
return;
}
*stream = fdopen(fd, fmode);
}
static task_id_t spawn(task_wait_t *wait, int argc, char *argv[])
{
const char **args;
task_id_t id = 0;
errno_t rc;
args = (const char **) calloc(argc + 1, sizeof(char *));
if (!args) {
fprintf(stderr, "No memory available\n");
return 0;
}
int i;
for (i = 0; i < argc; i++)
args[i] = argv[i];
args[argc] = NULL;
rc = task_spawnv(&id, wait, argv[0], args);
free(args);
if (rc != EOK) {
fprintf(stderr, "%s: Error spawning %s (%s)\n", NAME, argv[0],
str_error(rc));
return 0;
}
return id;
}
int main(int argc, char *argv[])
{
if (argc < 3) {
usage();
return -1;
}
int i;
for (i = 1; i < argc; i++) {
if (str_cmp(argv[i], "-i") == 0) {
i++;
if (i >= argc) {
usage();
return -2;
}
reopen(&stdin, 0, argv[i], 0, MODE_READ, "r");
} else if (str_cmp(argv[i], "-o") == 0) {
i++;
if (i >= argc) {
usage();
return -3;
}
reopen(&stdout, 1, argv[i], WALK_MAY_CREATE, MODE_WRITE,
"w");
} else if (str_cmp(argv[i], "-e") == 0) {
i++;
if (i >= argc) {
usage();
return -4;
}
reopen(&stderr, 2, argv[i], WALK_MAY_CREATE, MODE_WRITE,
"w");
} else if (str_cmp(argv[i], "--") == 0) {
i++;
break;
}
}
if (i >= argc) {
usage();
return -5;
}
setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
task_wait_t wait;
task_id_t id = spawn(&wait, argc - i, argv + i);
if (id != 0) {
task_exit_t texit;
int retval;
task_wait(&wait, &texit, &retval);
return retval;
}
return -6;
}
HelenOS homepage, sources at GitHub