process.c

早期freebsd实现

/* Asynchronous subprocess control for GNU Emacs.
   Copyright (C) 1985, 1986, 1987, 1988, 1990 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include <signal.h>

#include "config.h"

#ifdef subprocesses
/* The entire file is within this conditional */

#include <stdio.h>
#include <errno.h>
#include <setjmp.h>
#include <sys/types.h>		/* some typedefs are used in sys/file.h */
#include <sys/file.h>
#include <sys/stat.h>

#ifdef HAVE_SOCKETS	/* TCP connection support, if kernel can do it */
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#endif /* HAVE_SOCKETS */

#if defined(BSD) || defined(STRIDE)
#include <sys/ioctl.h>
#if !defined (O_NDELAY) && defined (HAVE_PTYS)
#include <fcntl.h>
#endif /* HAVE_PTYS and no O_NDELAY */
#endif /* BSD or STRIDE */
#ifdef USG
#include <termio.h>
#include <fcntl.h>
#endif /* USG */

#ifdef NEED_BSDTTY
#include <sys/bsdtty.h>
#endif

#ifdef HPUX
#undef TIOCGPGRP
#endif

#ifdef IRIS
#include <sys/sysmacros.h>	/* for "minor" */
#include <sys/time.h>
#else
#ifdef UNIPLUS
#include <sys/time.h>

#else /* not IRIS, not UNIPLUS */
#ifdef HAVE_TIMEVAL
/* _h_BSDTYPES is checked because on ISC unix, socket.h includes
   both time.h and sys/time.h, and the latter file is protected
   from repeated inclusion.  */
#if defined(USG) && !defined(AIX) && !defined(_h_BSDTYPES) && !defined(USG_SYS_TIME)
#include <time.h>
#else /* AIX or USG_SYS_TIME, or not USG */
#include <sys/time.h>
#endif /* AIX or USG_SYS_TIME, or not USG */
#endif /* HAVE_TIMEVAL */

#endif /* not UNIPLUS */
#endif /* not IRIS */

#if defined (HPUX) && defined (HAVE_PTYS)
#include <sys/ptyio.h>
#endif
  
#ifdef AIX
#include <sys/pty.h>
#include <unistd.h>
#endif /* AIX */

#ifdef SYSV_PTYS
#include <sys/tty.h>
#include <sys/pty.h>
#endif

#undef NULL
#include "lisp.h"
#include "window.h"
#include "buffer.h"
#include "process.h"
#include "termhooks.h"
#include "termopts.h"
#include "commands.h"

Lisp_Object Qrun, Qstop, Qsignal, Qexit, Qopen, Qclosed;

/* a process object is a network connection when its childp field is neither
   Qt nor Qnil but is instead a string (name of foreign host we
   are connected to + name of port we are connected to) */

#ifdef HAVE_SOCKETS
#define NETCONN_P(p) (XGCTYPE (XPROCESS (p)->childp) == Lisp_String)
#else
#define NETCONN_P(p) 0
#endif /* HAVE_SOCKETS */

/* Define SIGCHLD as an alias for SIGCLD.  There are many conditionals
   testing SIGCHLD.  */

#if !defined (SIGCHLD) && defined (SIGCLD)
#define SIGCHLD SIGCLD
#endif /* SIGCLD */

/* Define the structure that the wait system call stores.
   On many systems, there is a structure defined for this.
   But on vanilla-ish USG systems there is not.  */

#ifndef WAITTYPE
#if !defined (BSD) && !defined (UNIPLUS) && !defined (STRIDE) && !(defined (HPUX) && !defined (NOMULTIPLEJOBS)) && !defined (HAVE_WAIT_HEADER)
#define WAITTYPE int
#define WIFSTOPPED(w) ((w&0377) == 0177)
#define WIFSIGNALED(w) ((w&0377) != 0177 && (w&~0377) == 0)
#define WIFEXITED(w) ((w&0377) == 0)
#define WRETCODE(w) (w >> 8)
#define WSTOPSIG(w) (w >> 8)
#define WTERMSIG(w) (w & 0377)
#ifndef WCOREDUMP
#define WCOREDUMP(w) ((w&0200) != 0)
#endif
#else
#ifdef BSD4_1
#include <wait.h>
#else
#include <sys/wait.h>
#endif /* not BSD 4.1 */

#define WAITTYPE union wait
#ifndef WRETCODE
#define WRETCODE(w) w.w_retcode
#endif
#ifndef WCOREDUMP
#define WCOREDUMP(w) w.w_coredump
#endif

#ifdef HPUX
/* HPUX version 7 has broken definitions of these.  */
#undef WTERMSIG
#undef WSTOPSIG
#undef WIFSTOPPED
#undef WIFSIGNALED
#undef WIFEXITED
#endif

#ifndef WTERMSIG
#define WTERMSIG(w) w.w_termsig
#endif
#ifndef WSTOPSIG
#define WSTOPSIG(w) w.w_stopsig
#endif
#ifndef WIFSTOPPED
#define WIFSTOPPED(w) (WTERMSIG (w) == 0177)
#endif
#ifndef WIFSIGNALED
#define WIFSIGNALED(w) (WTERMSIG (w) != 0177 && (WSTOPSIG (w)) == 0)
#endif
#ifndef WIFEXITED
#define WIFEXITED(w) (WTERMSIG (w) == 0)
#endif
#endif /* BSD or UNIPLUS or STRIDE */
#endif /* no WAITTYPE */

#ifndef BSD4_4
extern errno;
extern sys_nerr;
extern char *sys_errlist[];
#endif

#ifndef BSD4_1
#ifndef BSD4_4
extern char *sys_siglist[];
#endif
#else
char *sys_siglist[] =
  {
    "bum signal!!",
    "hangup",
    "interrupt",
    "quit",
    "illegal instruction",
    "trace trap",
    "iot instruction",
    "emt instruction",
    "floating point exception",
    "kill",
    "bus error",
    "segmentation violation",
    "bad argument to system call",
    "write on a pipe with no one to read it",
    "alarm clock",
    "software termination signal from kill",
    "status signal",
    "sendable stop signal not from tty",
    "stop signal from tty",
    "continue a stopped process",
    "child status has changed",
    "background read attempted from control tty",
    "background write attempted from control tty",
    "input record available at control tty",
    "exceeded CPU time limit",
    "exceeded file size limit"
    };
#endif

#ifdef vipc

#include "vipc.h"
extern int comm_server;
extern int net_listen_address;
#endif /* vipc */

/* t means use pty, nil means use a pipe,
   maybe other values to come.  */
Lisp_Object Vprocess_connection_type;

#ifdef SKTPAIR
#ifndef HAVE_SOCKETS
#include <sys/socket.h>
#endif
#endif /* SKTPAIR */

/* Number of events of change of status of a process.  */
int process_tick;

/* Number of events for which the user or sentinel has been notified.  */
int update_tick;

int delete_exited_processes;

#ifdef FD_SET
/* We could get this from param.h, but better not to depend on finding that.
   And better not to risk that it might define other symbols used in this
   file.  */
#define MAXDESC 64
#define SELECT_TYPE fd_set
#else /* no FD_SET */
#define MAXDESC 32
#define SELECT_TYPE int

/* Define the macros to access a single-int bitmap of descriptors.  */
#define FD_SET(n, p) (*(p) |= (1 << (n)))
#define FD_CLR(n, p) (*(p) &= ~(1 << (n)))
#define FD_ISSET(n, p) (*(p) & (1 << (n)))
#define FD_ZERO(p) (*(p) = 0)
#endif /* no FD_SET */

/* Mask of bits indicating the descriptors that we wait for input on */

SELECT_TYPE input_wait_mask;

/* Indexed by descriptor, gives the process (if any) for that descriptor */
Lisp_Object chan_process[MAXDESC];

/* Alist of elements (NAME . PROCESS) */
Lisp_Object Vprocess_alist;

Lisp_Object Qprocessp;

Lisp_Object get_process ();

/* Buffered-ahead input char from process, indexed by channel.
   -1 means empty (no char is buffered).
   Used on sys V where the only way to tell if there is any
   output from the process is to read at least one char.
   Always -1 on systems that support FIONREAD.  */

int proc_buffered_char[MAXDESC];

/* These variables hold the filter about to be run, and its args,
   between read_process_output and run_filter.
   Also used in exec_sentinel for sentinels.  */
Lisp_Object this_filter;
Lisp_Object filter_process, filter_string;

/* Compute the Lisp form of the process status, p->status,
   from the numeric status that was returned by `wait'.  */

update_status (p)
     struct Lisp_Process *p;
{
  union { int i; WAITTYPE wt; } u;
  u.i = XFASTINT (p->raw_status_low) + (XFASTINT (p->raw_status_high) << 16);
  p->status = status_convert (u.wt);
  p->raw_status_low = Qnil;
  p->raw_status_high = Qnil;
}

/* Convert a process status word in Unix format
   to the list that we use internally.  */

Lisp_Object
status_convert (w)
     WAITTYPE w;
{
  if (WIFSTOPPED (w))
    return Fcons (Qstop, Fcons (make_number (WSTOPSIG (w)), Qnil));
  else if (WIFEXITED (w))
    return Fcons (Qexit, Fcons (make_number (WRETCODE (w)),
				WCOREDUMP (w) ? Qt : Qnil));
  else if (WIFSIGNALED (w))
    return Fcons (Qsignal, Fcons (make_number (WTERMSIG (w)),
				  WCOREDUMP (w) ? Qt : Qnil));
  else
    return Qrun;
}

/* Given a status-list, extract the three pieces of information
   and store them individually through the three pointers.  */

void
decode_status (l, symbol, code, coredump)
     Lisp_Object l;
     Lisp_Object *symbol;
     int *code;
     int *coredump;
{
  Lisp_Object tem;

  if (XTYPE (l) == Lisp_Symbol)
    {
      *symbol = l;
      *code = 0;
      *coredump = 0;
    }
  else
    {
      *symbol = XCONS (l)->car;
      tem = XCONS (l)->cdr;
      *code = XFASTINT (XCONS (tem)->car);
      tem = XFASTINT (XCONS (tem)->cdr);
      *coredump = !NULL (tem);
    }
}

/* Return a string describing a process status list.  */

Lisp_Object 
status_message (status)
     Lisp_Object status;
{
  Lisp_Object symbol;
  int code, coredump;
  Lisp_Object string, string2;

  decode_status (status, &symbol, &code, &coredump);

  if (EQ (symbol, Qsignal) || EQ (symbol, Qstop))
    {
      string = build_string (code < NSIG ? sys_siglist[code] : "unknown");
      string2 = build_string (coredump ? " (core dumped)\n" : "\n");
      XSTRING (string)->data[0] = DOWNCASE (XSTRING (string)->data[0]);
      return concat2 (string, string2);
    }
  else if (EQ (symbol, Qexit))
    {
      if (code == 0)
	return build_string ("finished\n");
      string = Fint_to_string (make_number (code));
      string2 = build_string (coredump ? " (core dumped)\n" : "\n");
      return concat2 (build_string ("exited abnormally with code "),
		      concat2 (string, string2));
    }
  else
    return Fcopy_sequence (Fsymbol_name (symbol));
}

#ifdef HAVE_PTYS

/* Open an available pty, returning a file descriptor.
   Return -1 on failure.
   The file name of the terminal corresponding to the pty
   is left in the variable pty_name.  */

char pty_name[24];

int
allocate_pty ()
{
  struct stat stb;
  register c, i;
  int fd;

#ifdef PTY_ITERATION
  PTY_ITERATION
#else
  for (c = FIRST_PTY_LETTER; c <= 'z'; c++)
    for (i = 0; i < 16; i++)
#endif
      {
#ifdef PTY_NAME_SPRINTF
	PTY_NAME_SPRINTF
#else
#ifdef HPUX
	sprintf (pty_name, "/dev/ptym/pty%c%x", c, i);
#else
#ifdef RTU
	sprintf (pty_name, "/dev/pty%x", i);
#else
	sprintf (pty_name, "/dev/pty%c%x", c, i);
#endif /* not RTU */
#endif /* not HPUX */
#endif /* no PTY_NAME_SPRINTF */

#ifndef IRIS
	if (stat (pty_name, &stb) < 0)
	  return -1;
#ifdef O_NONBLOCK
	fd = open (pty_name, O_RDWR | O_NONBLOCK, 0);
#else
	fd = open (pty_name, O_RDWR | O_NDELAY, 0);
#endif
#else /* Unusual IRIS code */
 	fd = open ("/dev/ptc", O_RDWR | O_NDELAY, 0);
 	if (fd < 0)
 	  return -1;
	if (fstat (fd, &stb) < 0)
	  return -1;
#endif /* IRIS */

	if (fd >= 0)
	  {
	    /* check to make certain that both sides are available
	       this avoids a nasty yet stupid bug in rlogins */
#ifdef PTY_TTY_NAME_SPRINTF
	    PTY_TTY_NAME_SPRINTF
#else
	    /* In version 19, make these special cases use the macro above.  */
#ifdef HPUX
            sprintf (pty_name, "/dev/pty/tty%c%x", c, i);
#else
#ifdef RTU
            sprintf (pty_name, "/dev/ttyp%x", i);
#else
#ifdef IRIS
 	    sprintf (pty_name, "/dev/ttyq%d", minor (stb.st_rdev));
#else
            sprintf (pty_name, "/dev/tty%c%x", c, i);
#endif /* not IRIS */
#endif /* not RTU */
#endif /* not HPUX */
#endif /* no PTY_TTY_NAME_SPRINTF */
#ifndef UNIPLUS
	    if (access (pty_name, 6) != 0)
	      {
		close (fd);
#ifndef IRIS
		continue;
#else
		return -1;
#endif /* IRIS */
	      }
#endif /* not UNIPLUS */
	    setup_pty (fd);
	    return fd;
	  }
      }
  return -1;
}
#endif /* HAVE_PTYS */

Lisp_Object
make_process (name)
     Lisp_Object name;
{