/* -*-C-*-

$Id: pruxenv.c,v 1.21 2003/02/14 18:28:23 cph Exp $

Copyright (c) 1990-2000 Massachusetts Institute of Technology

This file is part of MIT/GNU Scheme.

MIT/GNU Scheme 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 2 of the License, or (at
your option) any later version.

MIT/GNU Scheme 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 MIT/GNU Scheme; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA.

*/

/* Unix-specific process-environment primitives. */

#include "scheme.h"
#include "prims.h"
#include "ux.h"

#ifdef HAVE_SOCKETS
#  include "uxsock.h"
#endif

DEFINE_PRIMITIVE ("FILE-TIME->STRING", Prim_file_time_to_string, 1, 1,
  "Convert a file system time stamp into a date/time string.")
{
  PRIMITIVE_HEADER (1);
  CHECK_ARG (1, INTEGER_P);
  {
    time_t clock = (arg_integer (1));
    char * time_string = (UX_ctime (&clock));
    (time_string[24]) = '\0';
    PRIMITIVE_RETURN (char_pointer_to_string ((unsigned char *) time_string));
  }
}

DEFINE_PRIMITIVE ("GET-USER-HOME-DIRECTORY", Prim_get_user_home_directory, 1, 1,
  "Return the file name of a given user's home directory.\n\
The user name argument must be a string.\n\
If no such user is known, #F is returned.")
{
  PRIMITIVE_HEADER (1);
  {
    struct passwd * entry = (UX_getpwnam (STRING_ARG (1)));
    PRIMITIVE_RETURN
      ((entry == 0) ? SHARP_F
       : (char_pointer_to_string ((unsigned char *) (entry -> pw_dir))));
  }
}

DEFINE_PRIMITIVE ("UID->STRING", Prim_uid_to_string, 1, 1,
  "Return the user name corresponding to UID.\n\
If the argument is not a known user ID, #F is returned.")
{
  PRIMITIVE_HEADER (1);
  {
    struct passwd * entry = (UX_getpwuid (arg_nonnegative_integer (1)));
    PRIMITIVE_RETURN
      ((entry == 0) ? SHARP_F
       : (char_pointer_to_string ((unsigned char *) (entry -> pw_name))));
  }
}

DEFINE_PRIMITIVE ("GID->STRING", Prim_gid_to_string, 1, 1,
  "Return the group name corresponding to GID.\n\
If the argument is not a known group ID, #F is returned.")
{
  PRIMITIVE_HEADER (1);
  {
    struct group * entry = (UX_getgrgid (arg_nonnegative_integer (1)));
    PRIMITIVE_RETURN
      ((entry == 0) ? SHARP_F
       : (char_pointer_to_string ((unsigned char *) (entry -> gr_name))));
  }
}

DEFINE_PRIMITIVE ("CURRENT-PID", Prim_current_pid, 0, 0,
  "Return Scheme's PID.")
{
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (long_to_integer (UX_getpid ()));
}

DEFINE_PRIMITIVE ("CURRENT-UID", Prim_current_uid, 0, 0,
  "Return Scheme's effective UID.")
{
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (long_to_integer (UX_geteuid ()));
}

DEFINE_PRIMITIVE ("CURRENT-GID", Prim_current_gid, 0, 0,
  "Return Scheme's effective GID.")
{
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (long_to_integer (UX_getegid ()));
}

DEFINE_PRIMITIVE ("REAL-UID", Prim_real_uid, 0, 0,
  "Return Scheme's real UID.")
{
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (long_to_integer (UX_getuid ()));
}

DEFINE_PRIMITIVE ("REAL-GID", Prim_real_gid, 0, 0,
  "Return Scheme's real GID.")
{
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (long_to_integer (UX_getgid ()));
}

DEFINE_PRIMITIVE ("CURRENT-USER-NAME", Prim_current_user_name, 0, 0,
  "Return (as a string) the user name of the user running Scheme.")
{
  extern CONST char * EXFUN (OS_current_user_name, (void));
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN (char_pointer_to_string
		    ((unsigned char *) OS_current_user_name ()));
}

DEFINE_PRIMITIVE ("CURRENT-USER-HOME-DIRECTORY", Prim_current_user_home_directory, 0, 0,
  "Return the name of the current user's home directory.")
{
  extern CONST char * EXFUN (OS_current_user_home_directory, (void));
  PRIMITIVE_HEADER (0);
  PRIMITIVE_RETURN
    (char_pointer_to_string ((unsigned char *)
			     OS_current_user_home_directory ()));
}

DEFINE_PRIMITIVE ("SYSTEM", Prim_system, 1, 1,
  "Invoke sh (the Bourne shell) on the string argument.\n\
Wait until the shell terminates, returning its exit status as an integer.")
{
  PRIMITIVE_HEADER (1);
  PRIMITIVE_RETURN (long_to_integer (UX_system (STRING_ARG (1))));
}

DEFINE_PRIMITIVE ("GET-ENVIRONMENT-VARIABLE", Prim_get_environment_variable, 1, 1,
  "Look up the value of a variable in the user's shell environment.\n\
The argument, a variable name, must be a string.\n\
The result is either a string (the variable's value),\n\
 or #F indicating that the variable does not exist.")
{
  PRIMITIVE_HEADER (1);
  {
    CONST char * variable_value = (UX_getenv (STRING_ARG (1)));
    PRIMITIVE_RETURN
      ((variable_value == 0)
       ? SHARP_F
       : (char_pointer_to_string ((unsigned char *) variable_value)));
  }
}

#define HOSTNAMESIZE 1024

DEFINE_PRIMITIVE ("FULL-HOSTNAME", Prim_full_hostname, 0, 0,
  "Returns the full hostname (including domain if available) as a string.")
{
  PRIMITIVE_HEADER (0);
  {
    char this_host_name [HOSTNAMESIZE];
#ifdef HAVE_SOCKETS
    struct hostent * EXFUN (gethostbyname, (CONST char *));
    struct hostent * this_host_entry;

    STD_VOID_SYSTEM_CALL
      (syscall_gethostname,
       (UX_gethostname (this_host_name, HOSTNAMESIZE)));
#else
    strcpy (this_host_name, "unknown-host.unknown.unknown");
#endif

#ifdef HAVE_SOCKETS
    this_host_entry = (gethostbyname (this_host_name));
    PRIMITIVE_RETURN
      ((this_host_entry == 0)
       ? SHARP_F
       : (char_pointer_to_string
	  ((unsigned char *) (this_host_entry -> h_name))));
#else
    PRIMITIVE_RETURN
      (char_pointer_to_string ((unsigned char *) this_host_name));
#endif
  }
}

DEFINE_PRIMITIVE ("HOSTNAME", Prim_hostname, 0, 0,
  "Returns the hostname of the machine as a string.")
{
  PRIMITIVE_HEADER (0);
  {
    char this_host_name[HOSTNAMESIZE];

#ifdef HAVE_SOCKETS
    STD_VOID_SYSTEM_CALL (syscall_gethostname,
			  UX_gethostname (this_host_name, HOSTNAMESIZE));
    PRIMITIVE_RETURN
      (char_pointer_to_string ((unsigned char *) this_host_name));
#else
    strcpy (this_host_name, "unknown-host");
#endif
  }
}




DEFINE_PRIMITIVE ("INSTRUCTION-ADDRESS->COMPILED-CODE-BLOCK",
		  Prim_instruction_address_to_compiled_code_block, 1, 1, 0)
{
  PRIMITIVE_HEADER (1);
  {
      extern SCHEME_OBJECT find_ccblock(long);
      long the_pc = (INTEGER_P (ARG_REF (1)))
	? (integer_to_long (ARG_REF (1)))
	: ((long) OBJECT_ADDRESS (ARG_REF (1)));
      PRIMITIVE_RETURN (find_ccblock (the_pc));
  }
}

