setuidgid.c

daemontools-0.76.tar.gz是在linux环境下自动监控进程的源程序

#include <sys/types.h>
#include <pwd.h>
#include "prot.h"
#include "strerr.h"
#include "pathexec.h"

#define FATAL "setuidgid: fatal: "

const char *account;
struct passwd *pw;

int main(int argc,const char *const *argv,const char *const *envp)
{
  account = *++argv;
  if (!account || !*++argv)
    strerr_die1x(100,"setuidgid: usage: setuidgid account child");

  pw = getpwnam(account);
  if (!pw)
    strerr_die3x(111,FATAL,"unknown account ",account);

  if (prot_gid(pw->pw_gid) == -1)
    strerr_die2sys(111,FATAL,"unable to setgid: ");
  if (prot_uid(pw->pw_uid) == -1)
    strerr_die2sys(111,FATAL,"unable to setuid: ");

  pathexec_run(*argv,argv,envp);
  strerr_die4sys(111,FATAL,"unable to run ",*argv,": ");
}