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#include "lib.h"
#include <stdlib.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include "sys9.h"
#include "dir.h"
/*
* status not yet collected for processes that have exited
*/
typedef struct Waited Waited;
struct Waited {
Waitmsg* msg;
Waited* next;
};
static Waited *wd;
static Waitmsg *
lookpid(int pid)
{
Waited **wl, *w;
Waitmsg *msg;
for(wl = &wd; (w = *wl) != nil; wl = &w->next)
if(pid <= 0 || w->msg->pid == pid){
msg = w->msg;
*wl = w->next;
free(w);
return msg;
}
return 0;
}
static void
addpid(Waitmsg *msg)
{
Waited *w;
w = malloc(sizeof(*w));
if(w == nil){
/* lost it; what can we do? */
free(msg);
return;
}
w->msg = msg;
w->next = wd;
wd = w;
}
static int
waitstatus(Waitmsg *w)
{
int r, t;
char *bp, *ep;
r = 0;
t = 0;
if(w->msg[0]){
/* message is 'prog pid:string' */
bp = w->msg;
while(*bp){
if(*bp++ == ':')
break;
}
if(*bp == 0)
bp = w->msg;
r = strtol(bp, &ep, 10);
if(*ep == 0){
if(r < 0 || r >= 256)
r = 1;
}else{
t = _stringsig(bp);
if(t == 0)
r = 1;
}
}
return (r<<8) | t;
}
static void
waitresource(struct rusage *ru, Waitmsg *w)
{
memset(ru, 0, sizeof(*ru));
ru->ru_utime.tv_sec = w->time[0]/1000;
ru->ru_utime.tv_usec = (w->time[0]%1000)*1000;
ru->ru_stime.tv_sec = w->time[1]/1000;
ru->ru_stime.tv_usec = (w->time[1]%1000)*1000;
}
pid_t
wait(int *status)
{
return wait4(-1, status, 0, nil);
}
pid_t
waitpid(pid_t wpid, int *status, int options)
{
return wait4(wpid, status, options, nil);
}
pid_t
wait3(int *status, int options, struct rusage *res)
{
return wait4(-1, status, options, res);
}
pid_t
wait4(pid_t wpid, int *status, int options, struct rusage *res)
{
char pname[50];
Dir *d;
Waitmsg *w;
w = lookpid(wpid);
if(w == nil){
if(options & WNOHANG){
snprintf(pname, sizeof(pname), "/proc/%d/wait", getpid());
d = _dirstat(pname);
if(d != nil && d->length == 0){
free(d);
return 0;
}
free(d);
}
for(;;){
w = _WAIT();
if(w == nil){
_syserrno();
return -1;
}
if(wpid <= 0 || w->pid == wpid)
break;
addpid(w);
}
}
if(res != nil)
waitresource(res, w);
if(status != nil)
*status = waitstatus(w);
wpid = w->pid;
free(w);
return wpid;
}
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