xref: /aosp_15_r20/external/musl/src/internal/emulate_wait4.c (revision c9945492fdd68bbe62686c5b452b4dc1be3f8453)
1 #include <sys/wait.h>
2 #include "syscall.h"
3 
4 #ifndef SYS_wait4
__emulate_wait4(int pid,int * status,int options,void * kru,int cp)5 hidden long __emulate_wait4(int pid, int *status, int options, void *kru, int cp)
6 {
7 	idtype_t t;
8 	int r;
9 	siginfo_t info;
10 
11 	info.si_pid = 0;
12 	if (pid < -1) {
13 		t = P_PGID;
14 		pid = -pid;
15 	} else if (pid == -1) {
16 		t = P_ALL;
17 	} else if (pid == 0) {
18 		t = P_PGID;
19 	} else {
20 		t = P_PID;
21 	}
22 
23 	if (cp) r = __syscall_cp(SYS_waitid, t, pid, &info, options|WEXITED, kru);
24 	else r = __syscall(SYS_waitid, t, pid, &info, options|WEXITED, kru);
25 
26 	if (r<0) return r;
27 
28 	if (info.si_pid && status) {
29 		int sw=0;
30 		switch (info.si_code) {
31 		case CLD_CONTINUED:
32 			sw = 0xffff;
33 			break;
34 		case CLD_DUMPED:
35 			sw = info.si_status&0x7f | 0x80;
36 			break;
37 		case CLD_EXITED:
38 			sw = (info.si_status&0xff) << 8;
39 			break;
40 		case CLD_KILLED:
41 			sw = info.si_status&0x7f;
42 			break;
43 		case CLD_STOPPED:
44 		case CLD_TRAPPED:
45 			/* see ptrace(2); the high bits of si_status can contain */
46 			/* PTRACE_EVENT_ values which must be preserved */
47 			sw = (info.si_status << 8) + 0x7f;
48 			break;
49 		}
50 		*status = sw;
51 	}
52 
53 	return info.si_pid;
54 }
55 #endif
56