/* Fully extensible Emacs, running on Unix, intended for GNU.
   Copyright (C) 1985, 1986, 1987 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 <errno.h>

#include "config.h"
#include <stdio.h>

#include <sys/types.h>
#include <sys/file.h>

#ifdef VMS
#include <ssdef.h>
#endif

#ifdef USG5
#include <fcntl.h>
#endif

#ifdef BSD
#include <sys/ioctl.h>
#endif

#ifdef APOLLO
#ifndef APOLLO_SR10
#include <default_acl.h>
#endif
#endif

#undef NULL
#include "lisp.h"
#include "commands.h"

#ifndef O_RDWR
#define O_RDWR 2
#endif

#define PRIO_PROCESS 0

/* Command line args from shell, as list of strings */
Lisp_Object Vcommand_line_args;

/* Set nonzero after Emacs has started up the first time.
  Prevents reinitialization of the Lisp world and keymaps
  on subsequent starts.  */
int initialized;

/* Variable whose value is symbol giving operating system type */
Lisp_Object Vsystem_type;
  
/* If non-zero, emacs should not attempt to use an window-specific code,
   but instead should use the virtual terminal under which it was started */
int inhibit_window_system;

#ifdef HAVE_X_WINDOWS
/* If non-zero, -d was specified, meaning we're using some window system. */
int display_arg;
#endif

/* An address near the bottom of the stack.
   Tells GC how to save a copy of the stack.  */
char *stack_bottom;

#ifdef HAVE_X_WINDOWS
extern Lisp_Object Vwindow_system;
#endif /* HAVE_X_WINDOWS */

#ifdef USG_SHARED_LIBRARIES
/* If nonzero, this is the place to put the end of the writable segment
   at startup.  */

unsigned int bss_end = 0;
#endif

/* Nonzero means running Emacs without interactive terminal.  */

int noninteractive;

/* Value of Lisp variable `noninteractive'.
   Normally same as C variable `noninteractive'
   but nothing terrible happens if user sets this one.  */

int noninteractive1;

/* Signal code for the fatal signal that was received */
int fatal_error_code;

/* Nonzero if handling a fatal error already */
int fatal_error_in_progress;

/* Handle bus errors, illegal instruction, etc. */
fatal_error_signal (sig)
     int sig;
{
#ifdef BSD
  int tpgrp;
#endif /* BSD */

  fatal_error_code = sig;
  signal (sig, SIG_DFL);

  /* If fatal error occurs in code below, avoid infinite recursion.  */
  if (fatal_error_in_progress)
    kill (getpid (), fatal_error_code);

  fatal_error_in_progress = 1;

  /* If we are controlling the terminal, reset terminal modes */
#ifdef BSD
  if (ioctl(0, TIOCGPGRP, &tpgrp) == 0
      && tpgrp == getpgrp (0))
#endif /* BSD */
    {
      reset_sys_modes ();
      if (sig != SIGTERM)
	fprintf (stderr, "Fatal error (%d).", sig);
    }

  /* Clean up */
#ifdef subprocesses
  kill_buffer_processes (Qnil);
#endif
  Fdo_auto_save (Qt, Qnil);

#ifdef CLASH_DETECTION
  unlock_all_files ();
#endif /* CLASH_DETECTION */

#ifdef VMS
  kill_vms_processes ();
  LIB$STOP (SS$_ABORT);
#else
  /* Signal the same code; this time it will really be fatal.  */
  kill (getpid (), fatal_error_code);
#endif /* not VMS */
}

/* Code for dealing with Lisp access to the Unix command line */

static
init_cmdargs (argc, argv, skip_args)
     int argc;
     char **argv;
     int skip_args;
{
  register int i;

  Vcommand_line_args = Qnil;

  for (i = argc - 1; i >= 0; i--)
    {
      if (i == 0 || i > skip_args)
	Vcommand_line_args
	  = Fcons (build_string (argv[i]), Vcommand_line_args);
    }
}

#ifdef VMS
#ifdef LINK_CRTL_SHARE
#ifdef SHAREABLE_LIB_BUG
extern noshare char **environ;
#endif /* SHAREABLE_LIB_BUG */
#endif /* LINK_CRTL_SHARE */
#endif /* VMS */

/* ARGSUSED */
main (argc, argv, envp)
     int argc;
     char **argv;
     char **envp;
{
  char stack_bottom_variable;
  int skip_args = 0;
  extern int errno;
  extern sys_nerr;
  extern char *sys_errlist[];
  extern void malloc_warning ();

/* Map in shared memory, if we are using that.  */
#ifdef HAVE_SHM
  if (argc > 1 && !strcmp (argv[1], "-nl"))
    {
      map_in_data (0);
      /* The shared memory was just restored, which clobbered this.  */
      skip_args = 1;
    }
  else
    {
      map_in_data (1);
      /* The shared memory was just restored, which clobbered this.  */
      skip_args = 0;
    }
#endif

#ifdef HAVE_X_WINDOWS
  /* Stupid kludge to catch command-line display spec.  ask jla */
  {
    int i;

    for (i = 1; (i < argc && ! display_arg); i++)
      if (!strcmp (argv[i], "-d"))
	display_arg = 1;
  }
#endif

#ifdef VMS
  /* If -map specified, map the data file in */
  if (argc > 2 && ! strcmp (argv[1], "-map"))
    {
      skip_args = 2;
      mapin_data (argv[2]);
    }

#ifdef LINK_CRTL_SHARE
#ifdef SHAREABLE_LIB_BUG
  /* Bletcherous shared libraries! */
  if (!stdin)
    stdin = fdopen (0, "r");
  if (!stdout)
    stdout = fdopen (1, "w");
  if (!stderr)
    stderr = fdopen (2, "w");
  if (!environ)
    environ = envp;
#endif /* SHAREABLE_LIB_BUG */
#endif /* LINK_CRTL_SHARE */
#endif /* VMS */

  /* Record (approximately) where the stack begins.  */
  stack_bottom = &stack_bottom_variable;

#ifdef RUN_TIME_REMAP
  if (initialized)
    run_time_remap (argv[0]);
#endif

#ifdef USG_SHARED_LIBRARIES
  if (bss_end)
    brk (bss_end);
#endif

  clearerr (stdin);
#ifdef BSD
  setpgrp (0, getpid ());
#endif

#ifdef APOLLO
#ifndef APOLLO_SR10
  /* If USE_DOMAIN_ACLS environment variable exists,
     use ACLs rather than UNIX modes. */
  if (egetenv ("USE_DOMAIN_ACLS"))
    default_acl (USE_DEFACL);
#endif
#endif /* APOLLO */

#ifndef SYSTEM_MALLOC
  if (! initialized)
    malloc_init (0, malloc_warning);
#endif	/* not SYSTEM_MALLOC */

#ifdef HIGHPRI
  setpriority (PRIO_PROCESS, getpid (), HIGHPRI);
  setuid (getuid ());
#endif /* HIGHPRI */

#ifdef BSD
  /* interrupt_input has trouble if we aren't in a separate process group.  */
  setpgrp (getpid (), getpid ());
#endif

  inhibit_window_system = 0;

/* Handle the -t switch, which specifies filename to use as terminal */
  if (skip_args + 2 < argc && !strcmp (argv[skip_args + 1], "-t"))
    {
      int result;
      skip_args += 2;
      close (0);
      close (1);
      result = open (argv[skip_args], O_RDWR, 2 );
      if (result < 0)
	{
	  char *errstring;

	  if (errno >= 0 && errno < sys_nerr)
	    errstring = sys_errlist[errno];
	  else
	    errstring = "undocumented error code";
	  fprintf (stderr, "emacs: %s: %s\n", argv[skip_args], errstring);
	  exit (1);
	}
      dup (0);
      if (! isatty (0))
	{
	  fprintf (stderr, "emacs: %s: not a tty\n", argv[skip_args]);
	  exit (1);
	}
      fprintf (stderr, "Using %s\n", argv[skip_args]);
#ifdef HAVE_X_WINDOWS
      inhibit_window_system = 1;	/* -t => -nw */
#endif
    }

  if (skip_args + 1 < argc
      && (!strcmp (argv[skip_args + 1], "-nw")))
    {
      skip_args += 1;
      inhibit_window_system = 1;
    }

/* Handle the -batch switch, which means don't do interactive display.  */
  noninteractive = 0;
  if (skip_args + 1 < argc && !strcmp (argv[skip_args + 1], "-batch"))
    {
      skip_args += 1;
      noninteractive = 1;
    }

  if (
#ifndef CANNOT_DUMP
      ! noninteractive || initialized
#else
      1
#endif
      )
    {
      /* Don't catch these signals in batch mode if not initialized.
	 On some machines, this sets static data that would make
	 signal fail to work right when the dumped Emacs is run.  */
      signal (SIGHUP, fatal_error_signal);
      signal (SIGQUIT, fatal_error_signal);
      signal (SIGILL, fatal_error_signal);
      signal (SIGTRAP, fatal_error_signal);
      signal (SIGIOT, fatal_error_signal);
#ifdef SIGEMT
      signal (SIGEMT, fatal_error_signal);
#endif
      signal (SIGFPE, fatal_error_signal);
      signal (SIGBUS, fatal_error_signal);
      signal (SIGSEGV, fatal_error_signal);
      signal (SIGSYS, fatal_error_signal);
      signal (SIGTERM, fatal_error_signal);
#ifdef SIGXCPU
      signal (SIGXCPU, fatal_error_signal);
#endif
#ifdef SIGXFSZ
      signal (SIGXFSZ, fatal_error_signal);
#endif /* SIGXFSZ */

#ifdef AIX
      signal (SIGDANGER, fatal_error_signal);
      signal (20, fatal_error_signal);
      signal (21, fatal_error_signal);
      signal (22, fatal_error_signal);
      signal (23, fatal_error_signal);
      signal (24, fatal_error_signal);
      signal (SIGAIO, fatal_error_signal);
      signal (SIGPTY, fatal_error_signal);
      signal (SIGIOINT, fatal_error_signal);
      signal (SIGGRANT, fatal_error_signal);
      signal (SIGRETRACT, fatal_error_signal);
      signal (SIGSOUND, fatal_error_signal);
      signal (SIGMSG, fatal_error_signal);
#endif /* AIX */
    }

  noninteractive1 = noninteractive;

/* Perform basic initializations (not merely interning symbols) */

  if (!initialized)
    {
      init_alloc_once ();
      init_obarray ();
      init_eval_once ();
      init_syntax_once ();	/* Create standard syntax table.  */
		      /* Must be done before init_buffer */
      init_casetab_once ();
      init_buffer_once ();	/* Create buffer table and some buffers */
      init_minibuf_once ();	/* Create list of minibuffers */
			      /* Must precede init_window_once */
      init_window_once ();	/* Init the window system */
    }

  init_alloc ();
#ifdef MAINTAIN_ENVIRONMENT
  init_environ ();
#endif
  init_eval ();
  init_data ();
  init_read ();

  init_cmdargs (argc, argv, skip_args);	/* Create list Vcommand_line_args */
  init_buffer ();	/* Init default directory of main buffer */
  if (!noninteractive)
    {
#ifdef VMS
      init_vms_input ();/* init_display calls get_screen_size, that needs this */
#endif /* VMS */
      init_display ();	/* Determine terminal type.  init_sys_modes uses results */
    }
  init_keyboard ();	/* This too must precede init_sys_modes */
  init_callproc ();	/* And this too. */
#ifdef VMS
  init_vmsproc ();	/* And this too. */
#endif /* VMS */
  init_sys_modes ();	/* Init system terminal modes (RAW or CBREAK, etc.) */
  init_xdisp ();
  init_macros ();
  init_editfns ();
#ifdef LISP_FLOAT_TYPE
  init_floatfns ();
#endif
#ifdef VMS
  init_vmsfns ();
#endif /* VMS */
#ifdef subprocesses
  init_process ();
#endif /* subprocesses */

/* Intern the names of all standard functions and variables; define standard keys */

  if (!initialized)
    {
      /* The basic levels of Lisp must come first */
      /* And data must come first of all
	 for the sake of symbols like error-message */
      syms_of_data ();
      syms_of_alloc ();
#ifdef MAINTAIN_ENVIRONMENT
      syms_of_environ ();
#endif /* MAINTAIN_ENVIRONMENT */
      syms_of_read ();
      syms_of_print ();
      syms_of_eval ();
      syms_of_fns ();
#ifdef LISP_FLOAT_TYPE
      syms_of_floatfns ();
#endif

      syms_of_abbrev ();
      syms_of_buffer ();
      syms_of_bytecode ();
      syms_of_callint ();
      syms_of_casefiddle ();
      syms_of_casetab ();
      syms_of_callproc ();
      syms_of_cmds ();
#ifndef NO_DIR_LIBRARY
      syms_of_dired ();
#endif /* not NO_DIR_LIBRARY */
      syms_of_display ();
      syms_of_doc ();
      syms_of_editfns ();
      syms_of_emacs ();
      syms_of_fileio ();
#ifdef CLASH_DETECTION
      syms_of_filelock ();
#endif /* CLASH_DETECTION */
      syms_of_indent ();
      syms_of_keyboard ();
      syms_of_keymap ();
      syms_of_macros ();
      syms_of_marker ();
      syms_of_minibuf ();
      syms_of_mocklisp ();
#ifdef subprocesses
      syms_of_process ();
#endif /* subprocesses */
      syms_of_search ();
#ifdef MULTI_SCREEN
      syms_of_screen ();
#endif
      syms_of_syntax ();
      syms_of_undo ();
#ifdef VMS
      syms_of_vmsproc ();
#endif /* VMS */
      syms_of_window ();
      syms_of_xdisp ();
#ifdef HAVE_X_WINDOWS
      syms_of_xfns ();
#ifdef HAVE_X_MENU
      syms_of_xmenu ();
#endif /* HAVE_X_MENU */
#endif /* HAVE_X_WINDOWS */

#ifdef SYMS_SYSTEM
      SYMS_SYSTEM;
#endif

#ifdef SYMS_MACHINE
      SYMS_MACHINE;
#endif

      keys_of_casefiddle ();
      keys_of_cmds ();
      keys_of_buffer ();
      keys_of_keyboard ();
      keys_of_keymap ();
      keys_of_macros ();
      keys_of_minibuf ();
      keys_of_window ();
    }

  if (!initialized)
    {
      /* Handle -l loadup-and-dump, args passed by Makefile. */
      if (argc > 2 + skip_args && !strcmp (argv[1 + skip_args], "-l"))
	Vtop_level = Fcons (intern ("load"),
			    Fcons (build_string (argv[2 + skip_args]), Qnil));
#ifdef CANNOT_DUMP
      /* Unless next switch is -nl, load "loadup.el" first thing.  */
      if (!(argc > 1 + skip_args && !strcmp (argv[1 + skip_args], "-nl")))
	Vtop_level = Fcons (intern ("load"),
			    Fcons (build_string ("loadup.el"), Qnil));
#endif /* CANNOT_DUMP */
    }

  initialized = 1;

  /* Enter editor command loop.  This never returns.  */
  Frecursive_edit ();
  /* NOTREACHED */
}

DEFUN ("kill-emacs", Fkill_emacs, Skill_emacs, 0, 1, "P",
  "Exit the Emacs job and kill it.  Ask for confirmation, without argument.\n\
If ARG is an integer, return ARG as the exit program code.\n\
If ARG is a  string, stuff it as keyboard input.\n\n\
The value of `kill-emacs-hook', if not void,\n\
is a list of functions (of no args),\n\
all of which are called before Emacs is actually killed.")
  (arg)
     Lisp_Object arg;
{
  Lisp_Object hook, hook1;
  int i;
  struct gcpro gcpro1;

  GCPRO1 (arg);

  if (feof (stdin))
    arg = Qt;

  if (!NULL (Vrun_hooks) && !noninteractive)
    call1 (Vrun_hooks, intern ("kill-emacs-hook"));

#ifdef subprocesses
  kill_buffer_processes (Qnil);
#endif /* subprocesses */

#ifdef VMS
  kill_vms_processes ();
#endif /* VMS */

  Fdo_auto_save (Qt, Qnil);

#ifdef CLASH_DETECTION
  unlock_all_files ();
#endif /* CLASH_DETECTION */

  fflush (stdout);
  reset_sys_modes ();

#ifdef HAVE_X_WINDOWS
  if (!noninteractive && EQ (Vwindow_system, intern ("x")))
    Fx_close_current_connection ();
#endif /* HAVE_X_WINDOWS */

  UNGCPRO;

/* Is it really necessary to do this deassign
   when we are going to exit anyway?  */
/* #ifdef VMS
  stop_vms_input ();
 #endif  */
  stuff_buffered_input (arg);
#ifdef SIGIO
  /* There is a tendency for a SIGIO signal to arrive within exit,
     and cause a SIGHUP because the input descriptor is already closed.  */
  unrequest_sigio ();
  signal (SIGIO, SIG_IGN);
#endif
  exit ((XTYPE (arg) == Lisp_Int) ? XINT (arg)
#ifdef VMS
	: 1
#else
	: 0
#endif
	);
  /* NOTREACHED */
}

#ifndef CANNOT_DUMP
/* Nothing like this can be implemented on an Apollo.
   What a loss!  */

#ifdef HAVE_SHM

DEFUN ("dump-emacs-data", Fdump_emacs_data, Sdump_emacs_data, 1, 1, 0,
  "Dump current state of Emacs into data file FILENAME.\n\
This function exists on systems that use HAVE_SHM.")
  (intoname)
     Lisp_Object intoname;
{
  extern int my_edata;
  Lisp_Object tem;
  extern void malloc_warning ();

  CHECK_STRING (intoname, 0);
  intoname = Fexpand_file_name (intoname, Qnil);

  tem = Vpurify_flag;
  Vpurify_flag = Qnil;

  fflush (stdout);
  /* Tell malloc where start of impure now is */
  /* Also arrange for warnings when nearly out of space.  */
#ifndef SYSTEM_MALLOC
  malloc_init (&my_edata, malloc_warning);
#endif
  map_out_data (XSTRING (intoname)->data);

  Vpurify_flag = tem;

  return Qnil;
}

#else /* not HAVE_SHM */

DEFUN ("dump-emacs", Fdump_emacs, Sdump_emacs, 2, 2, 0,
  "Dump current state of Emacs into executable file FILENAME.\n\
Take symbols from SYMFILE (presumably the file you executed to run Emacs).\n\
This is used in the file `loadup.el' when building Emacs.\n\
\n\
Bind `command-line-processed' to nil before dumping,\n\
if you want the dumped Emacs to process its command line\n\
and announce itself normally when it is run.")
  (intoname, symname)
     Lisp_Object intoname, symname;
{
  extern int my_edata;
  Lisp_Object tem;
  extern void malloc_warning ();

  CHECK_STRING (intoname, 0);
  intoname = Fexpand_file_name (intoname, Qnil);
  if (!NULL (symname))
    {
      CHECK_STRING (symname, 0);
      if (XSTRING (symname)->size)
	symname = Fexpand_file_name (symname, Qnil);
    }

  tem = Vpurify_flag;
  Vpurify_flag = Qnil;

  fflush (stdout);
#ifdef VMS
  mapout_data (XSTRING (intoname)->data);
#else
  /* Tell malloc where start of impure now is */
  /* Also arrange for warnings when nearly out of space.  */
#ifndef SYSTEM_MALLOC
  malloc_init (&my_edata, malloc_warning);
#endif
  unexec (XSTRING (intoname)->data,
	  !NULL (symname) ? XSTRING (symname)->data : 0, &my_edata, 0, 0);
#endif /* not VMS */

  Vpurify_flag = tem;

  return Qnil;
}

#endif /* not HAVE_SHM */

#endif /* not CANNOT_DUMP */

#ifdef VMS
#define SEPCHAR ','
#else
#define SEPCHAR ':'
#endif

Lisp_Object
decode_env_path (evarname, defalt)
     char *evarname, *defalt;
{
  register char *path, *p;
  extern char *index ();

  Lisp_Object lpath;

  path = (char *) egetenv (evarname);
  if (!path)
    path = defalt;
  lpath = Qnil;
  while (1)
    {
      p = index (path, SEPCHAR);
      if (!p) p = path + strlen (path);
      lpath = Fcons (p - path ? make_string (path, p - path) : Qnil,
		     lpath);
      if (*p)
	path = p + 1;
      else
	break;
    }
  return Fnreverse (lpath);
}

syms_of_emacs ()
{
#ifdef HAVE_SHM
  defsubr (&Sdump_emacs_data);
#else
  defsubr (&Sdump_emacs);
#endif

  defsubr (&Skill_emacs);

  DEFVAR_LISP ("command-line-args", &Vcommand_line_args,
    "Args passed by shell to Emacs, as a list of strings.");

  DEFVAR_LISP ("system-type", &Vsystem_type,
    "Value is symbol indicating type of operating system you are using.");
  Vsystem_type = intern (SYSTEM_TYPE);

  DEFVAR_BOOL ("noninteractive", &noninteractive1,
    "Non-nil means Emacs is running without interactive terminal.");
}