int
noise_from_prog::execprog (const char *const *av)
{
int fds[2];
if (pipe (fds) < 0)
fatal ("pipe: %m\n");
pid = afork ();
if (!pid) {
close (fds[0]);
if (fds[1] != 1)
dup2 (fds[1], 1);
if (fds[1] != 2)
dup2 (fds[1], 2);
if (fds[1] != 1 && fds[1] != 2)
close (fds[1]);
close (0);
rc_ignore (chdir ("/"));
open ("/dev/null", O_RDONLY);
char *env[] = { NULL };
execve (av[0], const_cast<char *const *> (av), env);
//warn ("%s: %m\n", av[0]);
_exit (1);
}
close (fds[1]);
close_on_exec (fds[0]);
return fds[0];
}
void
getfilenoise (datasink *dst, const char *path, cbv cb, size_t maxbytes)
{
int fds[2];
if (pipe (fds) < 0)
fatal ("pipe: %m\n");
pid_t pid = afork ();
if (pid == -1)
(*cb) ();
else if (!pid) {
close (fds[0]);
int fd = open (path, O_RDONLY|O_NONBLOCK, 0);
if (fd < 0) {
fatal ("%s: %m\n", path);
_exit (1);
return;
}
for (;;) {
char buf[1024];
size_t n = read (fd, buf, min (maxbytes, sizeof (buf)));
if (n <= 0)
_exit (0);
v_write (fds[1], buf, n);
maxbytes -= n;
if (!maxbytes)
_exit (0);
}
}
else {
close (fds[1]);
close_on_exec (fds[0]);
getprognoise (dst, fds[0], pid, cb);
}
}
str
agent_userdir (u_int32_t uid, bool create)
{
int fd = open (".", O_RDONLY);
if (fd < 0) {
warn ("current working directory (.): %m\n");
return NULL;
}
const char *tmpdir = safegetenv ("TMPDIR");
if (!tmpdir || tmpdir[0] != '/')
tmpdir = "/tmp";
str ret;
struct stat sb;
uid_t myuid = getuid ();
if (chdir (tmpdir) < 0)
warn ("%s: %m\n", tmpdir);
else if (stat (".", &sb) < 0)
warn ("%s: %m\n", tmpdir);
else if ((sb.st_mode & 022) && !(sb.st_mode & 01000))
warn ("bad permissions on %s; chmod +t or set TMPDIR elsewhere", tmpdir);
else if (myuid == uid)
ret = agent_userdir_search (tmpdir, uid, create);
else if (!myuid) {
int fds[2];
if (pipe (fds) < 0)
warn ("pipe: %m\n");
else if (pid_t pid = afork ()) {
close (fds[1]);
strbuf sb;
while (sb.tosuio ()->input (fds[0]) > 0)
;
close (fds[0]);
int status = 1;
if (!waitpid (pid, &status, 0) && !status)
ret = sb;
}
else {
close (fds[0]);
_exit (setuid (uid)
|| !(ret = agent_userdir_search (tmpdir, uid, create))
|| (write (fds[1], ret, ret.len ())
!= implicit_cast<ssize_t> (ret.len ())));
}
}
rc_ignore (fchdir (fd));
close (fd);
return ret ? str (strbuf ("%s/", tmpdir) << ret) : str (NULL);
}
pid_t
spawn (const char *path, char *const *argv,
int in, int out, int err, cbv::ptr postforkcb, char *const *env)
{
int fds[2];
if (pipe (fds) < 0)
return -1;
close_on_exec (fds[0]);
close_on_exec (fds[1]);
pid_t pid = afork ();
if (pid < 0)
return pid;
if (!pid) {
amain_panic = true;
close (fds[0]);
setstdfds (in, out, err);
if (postforkcb)
(*postforkcb) ();
if (env)
execve (path, argv, env);
else
execv (path, argv);
int saved_err = errno;
v_write (fds[1], &saved_err, sizeof (saved_err));
close (fds[1]);
// Since we return a useful errno, there is no need to print
// anything in the child process. Just exit.
_exit (1);
}
close (fds[1]);
int chld_err;
int n = read (fds[0], &chld_err, sizeof (chld_err));
close (fds[0]);
if (n == 0)
return pid;
errno = chld_err;
return -1;
}
pid_t
aspawn (const char *path, char *const *argv,
int in, int out, int err, cbv::ptr postforkcb, char *const *env)
{
pid_t pid = afork ();
if (pid < 0)
return pid;
if (pid)
return pid;
setstdfds (in, out, err);
if (postforkcb)
(*postforkcb) ();
if (env)
execve (path, argv, env);
else
execv (path, argv);
warn ("%s: %m\n", path);
_exit (1);
}
