ports: qbe, cproc :^)

1 files changed, 82 insertions, 0 deletions

diff --git a/src/libc/spawn.c b/src/libc/spawn.c
new file mode 100644
index 0000000..c10b428
--- /dev/null
+++ b/src/libc/spawn.c
@@ -0,0 +1,82 @@
+#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;
+}