src/runtime/run-program.c

   1 /*
   2  * support for the Lisp function RUN-PROGRAM and friends
   3  */
   4
   5 /*
   6  * This software is part of the SBCL system. See the README file for
   7  * more information.
   8  *
   9  * This software is derived from the CMU CL system, which was
  10  * written at Carnegie Mellon University and released into the
  11  * public domain. The software is in the public domain and is
  12  * provided with absolutely no warranty. See the COPYING and CREDITS
  13  * files for more information.
  14  */
  15
  16 #include <stdlib.h>
  17 #include <sys/file.h>
  18 #include <sys/types.h>
  19 #include <sys/stat.h>
  20 #include <fcntl.h>
  21 #include <sys/ioctl.h>
  22 #if defined(SVR4) || defined(__linux__)
  23 #include <unistd.h>
  24 #endif
  25
  26 #include <sys/ioctl.h>
  27 #include <termios.h>
  28
  29
  30 /* borrowed from detachtty's detachtty.c, in turn borrowed from APUE
  31  * example code found at
  32  * http://www.yendor.com/programming/unix/apue/pty/main.c
  33
  34 -brkint
  35
  36  */
  37
  38 int set_noecho(int fd)
  39 {
  40     struct termios  stermios;
  41
  42     if (tcgetattr(fd, &stermios) < 0) return 0;
  43
  44     stermios.c_lflag &= ~(  ECHO | /* ECHOE |  ECHOK | */  ECHONL);
  45     stermios.c_oflag |= (ONLCR);
  46     stermios.c_iflag &= ~(BRKINT);
  47     stermios.c_iflag |= (ICANON|ICRNL);
  48
  49     stermios.c_cc[VERASE]=0177;
  50     if (tcsetattr(fd, TCSANOW, &stermios) < 0) return 0;
  51     return 1;
  52 }
  53
  54 int spawn(char *program, char *argv[], char *envp[], char *pty_name,
  55           int stdin, int stdout, int stderr)
  56 {
  57     int pid = fork();
  58     int fd;
  59
  60     if (pid != 0)
  61         return pid;
  62
  63     /* Put us in our own process group. */
  64 #if defined(hpux)
  65     setsid();
  66 #elif defined(SVR4) || defined(__linux__)
  67     setpgrp();
  68 #else
  69     setpgrp(0, getpid());
  70 #endif
  71
  72     /* If we are supposed to be part of some other pty, go for it. */
  73     if (pty_name) {
  74 #if !defined(hpux) && !defined(SVR4)
  75         fd = open("/dev/tty", O_RDWR, 0);
  76         if (fd >= 0) {
  77             ioctl(fd, TIOCNOTTY, 0);
  78             close(fd);
  79         }
  80 #endif
  81         fd = open(pty_name, O_RDWR, 0);
  82         dup2(fd, 0);
  83         set_noecho(0);
  84         dup2(fd, 1);
  85         dup2(fd, 2);
  86         close(fd);
  87     } else{
  88     /* Set up stdin, stdout, and stderr */
  89     if (stdin >= 0)
  90         dup2(stdin, 0);
  91     if (stdout >= 0)
  92         dup2(stdout, 1);
  93     if (stderr >= 0)
  94         dup2(stderr, 2);
  95     }
  96     /* Close all other fds. */
  97 #ifdef SVR4
  98     for (fd = sysconf(_SC_OPEN_MAX)-1; fd >= 3; fd--)
  99         close(fd);
 100 #else
 101     for (fd = getdtablesize()-1; fd >= 3; fd--)
 102         close(fd);
 103 #endif
 104
 105     /* Exec the program. */
 106     execve(program, argv, envp);
 107
 108     /* It didn't work, so try /bin/sh. */
 109     argv[0] = program;
 110     argv[-1] = "sh";
 111     execve("/bin/sh", argv-1, envp);
 112
 113     /* The exec didn't work, flame out. */
 114     exit(1);
 115 }