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#ifndef lint
static char *sccsid = "@(#)$Header: spawn.c,v 1.22 91/02/08 18:30:30 sob Exp $";
#endif
#include "common.h"
#include <signal.h>
#ifdef sparc
#include <vfork.h>
#endif
#ifdef XFER_TIMEOUT
static int xfer_lines;
static int old_xfer_lines;
#endif
static char tempfile[256];
#ifndef CNEWS
static char badfile[256];
#endif
/*
* spawn -- create a child process with the input from the client
* as stdin.
*
* Parameters: "path" is the path of the program to invoke.
* "name" is the name to call the program.
* "flag" is a single flag to be passed to the program.
* "cont_code" is the response code to transmit
* on successful startup.
* "err_code" is the response code to transmit when
* something goes wrong.
*
* Returns: -1 on non-zero return from child,
* 0 on error before fork/exec,
* 1 otherwise.
*
* Side effects: Creates and removes temporary file;
* accepts input from client; forks and execs.
* Can time out if XFER_TIMEOUT is defined.
*/
spawn(path, name, flag, cont_code, err_code, errbuf, msg_id)
char *path;
char *name;
char *flag;
int cont_code;
int err_code;
char *errbuf;
char *msg_id;
{
char line[NNTP_STRLEN];
register char *cp;
int i, fd;
int fds[2];
int pid, npid;
int exit_status = 1;
#ifdef POSTER
char *envp[4], user[sizeof(POSTER) + 5], logname[sizeof(POSTER) + 8];
char *home;
#else
char *envp[1];
#endif
#ifdef XFER_TIMEOUT
int xfer_timeout();
#endif
#ifdef USG
int status;
#else not USG
union wait status;
#endif not USG
register FILE *fp;
#ifdef CNEWS
(void) strcpy(tempfile, "/usr/tmp/rpostXXXXXX");
#else
sprintf(tempfile, "%s/.tmp/rpostXXXXXX",SPOOLDIR);
#endif
(void) mktemp(tempfile);
fp = fopen(tempfile, "w");
if (fp == NULL) {
printf("%d Cannot create temporary file.\r\n", err_code);
(void) fflush(stdout);
return (0);
}
#ifdef AUTH
/*
* If this is a posting, rather than an XFER, leave a trail of
* breadcrumbs by stuffing where it came from into the header
*/
if (cont_code == CONT_POST)
fprintf(fp, "Nntp-Posting-Host: %s\n", hostname);
#endif AUTH
printf("%d Ok\r\n", cont_code);
(void) fflush(stdout);
#ifdef XFER_TIMEOUT
xfer_lines = old_xfer_lines = 0;
signal(SIGALRM, xfer_timeout);
(void) alarm(XFER_TIMEOUT);
#endif
while (fgets(line, sizeof(line), stdin) != NULL) {
#ifdef XFER_TIMEOUT
xfer_lines++;
#endif
if ((cp = index(line, '\r')) != NULL)
*cp = '\0';
else if ((cp = index(line, '\n')) != NULL)
*cp = '\0';
if (line[0] == '.' && line[1] == '\0')
break;
if (line[0] == '.')
fputs(line+1, fp);
else
fputs(line, fp);
putc('\n', fp);
}
(void) fclose(fp);
#ifdef XFER_TIMEOUT
(void) alarm(0);
(void) signal(SIGALRM, SIG_DFL);
#endif
/* See if the connection got closed somehow... */
if (line[0] != '.' && line[1] != '\0') {
(void) unlink(tempfile);
#ifdef SYSLOG
# ifdef LOG
syslog(LOG_ERR,
"%s spawn: EOF before period on line by itself %s",
hostname, msg_id);
# else
syslog(LOG_ERR,
"spawn: EOF before period on line by itself %s", msg_id);
# endif
#endif
return (0);
}
#ifdef POSTER
if (tempfile[0])
(void) chown(tempfile, uid_poster, gid_poster);
#endif
/* Set up a pipe so we can see errors from rnews */
if (pipe(fds) < 0) {
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: pipe: %m");
#endif
(void) unlink(tempfile);
return (-1);
}
/*
* Ok, now we have the article in "tempfile". We
* should be able to fork off, close fd's 0 to 31 (or
* whatever), open "tempfile" for input, thus making
* it stdin, and then execle the inews. We think.
*/
#ifdef SYSLOG
/*
* Close in such a way that syslog() will know to reopen.
* We must do this before the vfork() otherwise the parent
* will think the syslog fd is closed and open a new one,
* eventually using up all the available file descriptors.
*/
closelog();
#endif
pid = vfork();
if (pid == 0) { /* We're in child */
#ifdef POSTER
#ifndef USG
if (getuid() == 0) initgroups(POSTER,gid_poster);
#endif
(void) setgid(gid_poster);
(void) setuid(uid_poster);
#endif
/* Set up stdout and stderr for child */
if (fds[1] != 1) {
(void) dup2(fds[1], 1);
(void) close(fds[1]);
}
(void) dup2(1, 2);
for (i = 3; i < 10; ++i) /* XXX but getdtablesize is too big */
(void) close(i);
fd = open(tempfile, O_RDONLY);
if (fd != 0) {
(void) dup2(fd, 0);
(void) close(fd);
}
/* Empty environment keeps cnews inews from telling lies */
#ifdef POSTER
sprintf(user, "USER=%s", POSTER);
sprintf(logname, "LOGNAME=%s", POSTER);
if ((home = (char *)malloc(strlen(home_poster)+5)) != NULL)
sprintf(home, "HOME=%s", home_poster);
envp[0] = user;
envp[1] = logname;
envp[2] = home;
envp[3] = 0;
#else
envp[0] = 0;
#endif
#ifdef USG
/* execle() fails if name is a shell procedure */
execle("/bin/sh", "sh", path, flag, (char *)NULL, envp);
#else
execle(path, name, flag, (char *) NULL, envp);
#endif
fprintf(stderr, "spawn: execle(%s)", path);
perror(path);
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: execle(%s): %m", path);
#endif
_exit(-1); /* Error */
/*NOTREACHED*/
} else { /* We're in parent. */
if (pid == -1) {
/* fork failed! */
printf("%d Cannot fork %s\r\n", err_code, path);
(void) fflush(stdout);
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: fork: %m");
#endif
(void) unlink(tempfile);
return (0);
}
(void) close(fds[1]);
fp = fdopen(fds[0], "r");
if (fp == NULL) {
printf("%d Cannot fdopen %s pipe\r\n", err_code, path);
(void) fflush(stdout);
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: pipe: %m");
#endif
(void) unlink(tempfile);
return (0);
}
if (errbuf)
*errbuf = '\0';
while (fgets(line, sizeof (line), fp) != NULL) {
if (line[0] != '\n') {
if (errbuf) {
if (cp = index(line, '\n'))
*cp = '\0';
(void) strcat(errbuf, line);
}
#ifdef SYSLOG
syslog(LOG_INFO, "%s: %s", path, line);
#endif
}
}
while ((npid = wait(&status)) > 0)
if (npid == pid) {
#ifdef USG
exit_status = (status >> 8) & 0xff;
#else /* not USG */
exit_status = status.w_T.w_Retcode;
#endif /*not USG */
break;
}
(void) fclose(fp);
(void) fflush(stdout);
if (npid < 0) {
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: wait pid %d: %m", pid);
#endif
return (-1);
}
#ifdef notdef
/* Make ctags happy */
{
#endif
if (exit_status != 0) {
#ifdef SYSLOG
syslog(LOG_ERR, "spawn: %s exit status %d",
path, exit_status);
#endif
/*
* Save the tempfile away in .bad.
*/
#ifdef CNEWS
}
(void) unlink(tempfile);
#else
sprintf(badfile, "%s/.bad/nntpXXXXXX",SPOOLDIR);
(void) mktemp(badfile);
(void) rename(tempfile, badfile);
} else {
(void) unlink(tempfile);
}
#endif
return (exit_status ? -1 : 1);
}
}
#ifdef XFER_TIMEOUT
xfer_timeout()
{
if (old_xfer_lines < xfer_lines) {
old_xfer_lines = xfer_lines;
(void) alarm(XFER_TIMEOUT);
return;
}
/* Timed out. */
printf("%d timeout after %d seconds, closing connection.\r\n",
ERR_FAULT, XFER_TIMEOUT);
fflush(stdout);
#ifdef LOG
syslog(LOG_ERR, "%s transfer_timeout", hostname);
#endif LOG
(void) unlink(tempfile);
exit(1);
}
#endif XFER_TIMEOUT
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.