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#include <camellia/syscalls.h>
#include <errno.h>
#include <spawn.h>
#include <stdlib.h>
#include <unistd.h>
enum act {
ACT_DUP2 = 1,
};
struct file_action {
struct file_action *next;
enum act type;
int a, b;
};
int
posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *facts, int from, int to)
{
struct file_action *fact, **tail;
fact = calloc(1, sizeof(*fact));
if (!fact) return ENOMEM;
fact->type = ACT_DUP2;
fact->a = from;
fact->b = to;
tail = &facts->f;
while (*tail) {
tail = &(*tail)->next;
}
*tail = fact;
return 0;
}
int
posix_spawn_file_actions_destroy(posix_spawn_file_actions_t *facts)
{
while (facts->f) {
struct file_action *cur = facts->f;
facts->f = cur->next;
free(cur);
}
return 0;
}
int
posix_spawn_file_actions_init(posix_spawn_file_actions_t *facts)
{
facts->f = NULL;
return 0;
}
int
posix_spawnp(
pid_t *restrict pidp,
const char *restrict file,
const posix_spawn_file_actions_t *restrict facts,
const posix_spawnattr_t *restrict attrp,
char *const argv[restrict],
char *const envp[restrict]
) {
if (attrp) return ENOSYS;
pid_t pid = fork();
if (pid < 0) return errno;
if (pid == 0) {
struct file_action *fact = facts ? facts->f : NULL;
while (fact) {
switch (fact->type) {
case ACT_DUP2:
dup2(fact->a, fact->b);
break;
}
fact = fact->next;
}
execvpe(file, argv, envp);
_sys_exit(127);
}
if (pidp) *pidp = pid;
return 0;
}
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