code:
/* classes: h_files */

#ifndef SCM_EVAL_H
#define SCM_EVAL_H

/* Copyright (C) 1995,1996,1998,1999,2000,2001,2002,2003,2004
 * Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"

#include "libguile/struct.h"

/* {Options}
 */

SCM_API scm_t_option scm_eval_opts[];

#define SCM_EVAL_STACK         scm_eval_opts[0].val
#define SCM_N_EVAL_OPTIONS 1

SCM_API long scm_eval_stack;

SCM_API scm_t_option scm_evaluator_trap_table[];

SCM_API SCM scm_eval_options_interface (SCM setting);

#define SCM_TRAPS_P	       scm_evaluator_trap_table[0].val
#define SCM_ENTER_FRAME_P      scm_evaluator_trap_table[1].val
#define SCM_APPLY_FRAME_P      scm_evaluator_trap_table[2].val
#define SCM_EXIT_FRAME_P       scm_evaluator_trap_table[3].val
#define SCM_ENTER_FRAME_HDLR   (SCM_PACK (scm_evaluator_trap_table[4].val))
#define SCM_APPLY_FRAME_HDLR   (SCM_PACK (scm_evaluator_trap_table[5].val))
#define SCM_EXIT_FRAME_HDLR    (SCM_PACK (scm_evaluator_trap_table[6].val))
#define SCM_N_EVALUATOR_TRAPS 7

/* {Ilocs}
 *
 * Ilocs are relative pointers into local environment structures.
 *
 */
#define SCM_ILOCP(n)		(SCM_ITAG8(n)==scm_tc8_iloc)

/* {Promises}
 */

#define SCM_F_PROMISE_COMPUTED (1L << 0)
#define SCM_PROMISE_COMPUTED_P(promise) \
  (SCM_F_PROMISE_COMPUTED & SCM_SMOB_FLAGS (promise))
#define SCM_SET_PROMISE_COMPUTED(promise) \
  SCM_SET_SMOB_FLAGS ((promise), SCM_F_PROMISE_COMPUTED)
#define SCM_PROMISE_MUTEX     SCM_SMOB_OBJECT_2
#define SCM_PROMISE_DATA      SCM_SMOB_OBJECT
#define SCM_SET_PROMISE_DATA  SCM_SET_SMOB_OBJECT

SCM_API scm_t_bits scm_tc16_promise;

/* {Evaluator}
 */

typedef SCM (*scm_t_trampoline_0) (SCM proc);
typedef SCM (*scm_t_trampoline_1) (SCM proc, SCM arg1);
typedef SCM (*scm_t_trampoline_2) (SCM proc, SCM arg1, SCM arg2);

#define SCM_EXTEND_ENV scm_acons

/*fixme* This should probably be removed throught the code. */

#define SCM_TOP_LEVEL_LOOKUP_CLOSURE (scm_current_module_lookup_closure())

SCM_API SCM scm_sym_and;
SCM_API SCM scm_sym_begin;
SCM_API SCM scm_sym_case;
SCM_API SCM scm_sym_cond;
SCM_API SCM scm_sym_define;
SCM_API SCM scm_sym_do;
SCM_API SCM scm_sym_if;
SCM_API SCM scm_sym_lambda;
SCM_API SCM scm_sym_let;
SCM_API SCM scm_sym_letstar;
SCM_API SCM scm_sym_letrec;
SCM_API SCM scm_sym_quote;
SCM_API SCM scm_sym_quasiquote;
SCM_API SCM scm_sym_unquote;
SCM_API SCM scm_sym_uq_splicing;

SCM_API SCM scm_sym_atapply;
SCM_API SCM scm_sym_atcall_cc;
SCM_API SCM scm_sym_at_call_with_values;
SCM_API SCM scm_sym_delay;
SCM_API SCM scm_sym_arrow;
SCM_API SCM scm_sym_else;
SCM_API SCM scm_sym_apply;
SCM_API SCM scm_sym_set_x;
SCM_API SCM scm_sym_args;

SCM_API SCM * scm_ilookup (SCM iloc, SCM env);
SCM_API SCM * scm_lookupcar (SCM vloc, SCM genv, int check);
SCM_API SCM scm_eval_car (SCM pair, SCM env);
SCM_API SCM scm_eval_body (SCM code, SCM env);
SCM_API SCM scm_eval_args (SCM i, SCM env, SCM proc);
SCM_API SCM scm_m_quote (SCM xorig, SCM env);
SCM_API SCM scm_m_begin (SCM xorig, SCM env);
SCM_API SCM scm_m_if (SCM xorig, SCM env);
SCM_API SCM scm_m_set_x (SCM xorig, SCM env);
SCM_API SCM scm_m_vref (SCM xorig, SCM env);
SCM_API SCM scm_m_vset (SCM xorig, SCM env);
SCM_API SCM scm_m_and (SCM xorig, SCM env);
SCM_API SCM scm_m_or (SCM xorig, SCM env);
SCM_API SCM scm_m_case (SCM xorig, SCM env);
SCM_API SCM scm_m_cond (SCM xorig, SCM env);
SCM_API SCM scm_m_lambda (SCM xorig, SCM env);
SCM_API SCM scm_m_letstar (SCM xorig, SCM env);
SCM_API SCM scm_m_do (SCM xorig, SCM env);
SCM_API SCM scm_m_quasiquote (SCM xorig, SCM env);
SCM_API SCM scm_m_delay (SCM xorig, SCM env);
SCM_API SCM scm_m_generalized_set_x (SCM xorig, SCM env);
SCM_API SCM scm_m_future (SCM xorig, SCM env);
SCM_API SCM scm_m_define (SCM x, SCM env);
SCM_API SCM scm_m_letrec (SCM xorig, SCM env);
SCM_API SCM scm_m_let (SCM xorig, SCM env);
SCM_API SCM scm_m_apply (SCM xorig, SCM env);
SCM_API SCM scm_m_cont (SCM xorig, SCM env);
#if SCM_ENABLE_ELISP
SCM_API SCM scm_m_nil_cond (SCM xorig, SCM env);
SCM_API SCM scm_m_atfop (SCM xorig, SCM env);
#endif /* SCM_ENABLE_ELISP */
SCM_API SCM scm_m_atbind (SCM xorig, SCM env);
SCM_API SCM scm_m_atslot_ref (SCM xorig, SCM env);
SCM_API SCM scm_m_atslot_set_x (SCM xorig, SCM env);
SCM_API SCM scm_m_atdispatch (SCM xorig, SCM env);
SCM_API SCM scm_m_at_call_with_values (SCM xorig, SCM env);
SCM_API int scm_badargsp (SCM formals, SCM args);
SCM_API SCM scm_call_0 (SCM proc);
SCM_API SCM scm_call_1 (SCM proc, SCM arg1);
SCM_API SCM scm_call_2 (SCM proc, SCM arg1, SCM arg2);
SCM_API SCM scm_call_3 (SCM proc, SCM arg1, SCM arg2, SCM arg3);
SCM_API SCM scm_call_4 (SCM proc, SCM arg1, SCM arg2, SCM arg3, SCM arg4);
SCM_API SCM scm_apply_0 (SCM proc, SCM args);
SCM_API SCM scm_apply_1 (SCM proc, SCM arg1, SCM args);
SCM_API SCM scm_apply_2 (SCM proc, SCM arg1, SCM arg2, SCM args);
SCM_API SCM scm_apply_3 (SCM proc, SCM arg1, SCM arg2, SCM arg3, SCM args);
SCM_API SCM scm_i_call_closure_0 (SCM proc);
SCM_API scm_t_trampoline_0 scm_trampoline_0 (SCM proc);
SCM_API scm_t_trampoline_1 scm_trampoline_1 (SCM proc);
SCM_API scm_t_trampoline_2 scm_trampoline_2 (SCM proc);
SCM_API SCM scm_nconc2last (SCM lst);
SCM_API SCM scm_apply (SCM proc, SCM arg1, SCM args);
SCM_API SCM scm_dapply (SCM proc, SCM arg1, SCM args);
SCM_API SCM scm_map (SCM proc, SCM arg1, SCM args);
SCM_API SCM scm_for_each (SCM proc, SCM arg1, SCM args);
SCM_API SCM scm_closure (SCM code, SCM env);
SCM_API SCM scm_makprom (SCM code);
SCM_API SCM scm_force (SCM x);
SCM_API SCM scm_promise_p (SCM x);
SCM_API SCM scm_cons_source (SCM xorig, SCM x, SCM y);
SCM_API SCM scm_copy_tree (SCM obj);
SCM_API SCM scm_i_eval_x (SCM exp, SCM env);
SCM_API SCM scm_i_eval (SCM exp, SCM env);
SCM_API SCM scm_primitive_eval (SCM exp);
SCM_API SCM scm_primitive_eval_x (SCM exp);
SCM_API SCM scm_eval (SCM exp, SCM module);
SCM_API SCM scm_eval_x (SCM exp, SCM module);

SCM_API void scm_i_print_iloc (SCM /*iloc*/, SCM /*port*/);
SCM_API void scm_i_print_isym (SCM /*isym*/, SCM /*port*/);
SCM_API SCM scm_i_unmemocopy_expr (SCM expr, SCM env);
SCM_API SCM scm_i_unmemocopy_body (SCM forms, SCM env);
SCM_API void scm_init_eval (void);

#if (SCM_ENABLE_DEPRECATED == 1)

SCM_API SCM scm_m_undefine (SCM x, SCM env);

/* Deprecated in guile 1.7.0 on 2003-11-09.  */
SCM_API SCM scm_m_expand_body (SCM xorig, SCM env);

/* Deprecated in guile 1.7.0 on 2003-11-16.  */
SCM_API SCM scm_unmemocar (SCM form, SCM env);
SCM_API SCM scm_macroexp (SCM x, SCM env);

/* Deprecated in guile 1.7.0 on 2004-03-29.  */
SCM_API SCM scm_ceval (SCM x, SCM env);
SCM_API SCM scm_deval (SCM x, SCM env);
SCM_API SCM (*scm_ceval_ptr) (SCM x, SCM env);

#endif

#endif  /* SCM_EVAL_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/

license: unknown


code:
/* Copyright (C) 1998,1999,2000,2001,2002,2003, 2006, 2008 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include "libguile/_scm.h"
#include "libguile/eval.h"
#include "libguile/fluids.h"
#include "libguile/modules.h"

#include "libguile/validate.h"
#include "libguile/evalext.h"

SCM_DEFINE (scm_defined_p, "defined?", 1, 1, 0,
            (SCM sym, SCM env),
	    "Return @code{#t} if @var{sym} is defined in the lexical "
	    "environment @var{env}.  When @var{env} is not specified, "
	    "look in the top-level environment as defined by the "
	    "current module.")
#define FUNC_NAME s_scm_defined_p
{
  SCM var;

  SCM_VALIDATE_SYMBOL (1, sym);

  if (SCM_UNBNDP (env))
    var = scm_sym2var (sym, scm_current_module_lookup_closure (),
			 SCM_BOOL_F);
  else
    {
      SCM frames = env;
      register SCM b;
      for (; SCM_NIMP (frames); frames = SCM_CDR (frames))
	{
	  SCM_ASSERT (scm_is_pair (frames), env, SCM_ARG2, FUNC_NAME);
	  b = SCM_CAR (frames);
	  if (scm_is_true (scm_procedure_p (b)))
	    break;
	  SCM_ASSERT (scm_is_pair (b), env, SCM_ARG2, FUNC_NAME);
	  for (b = SCM_CAR (b); SCM_NIMP (b); b = SCM_CDR (b))
	    {
	      if (!scm_is_pair (b))
		{
		  if (scm_is_eq (b, sym))
		    return SCM_BOOL_T;
		  else
		    break;
		}
	      if (scm_is_eq (SCM_CAR (b), sym))
		return SCM_BOOL_T;
	    }
	}
      var = scm_sym2var (sym,
			 SCM_NIMP (frames) ? SCM_CAR (frames) : SCM_BOOL_F,
			 SCM_BOOL_F);
    }

  return (scm_is_false (var) || SCM_UNBNDP (SCM_VARIABLE_REF (var))
	  ? SCM_BOOL_F
	  : SCM_BOOL_T);
}
#undef FUNC_NAME

SCM_REGISTER_PROC (s_map_in_order, "map-in-order", 2, 0, 1, scm_map);

SCM_DEFINE (scm_self_evaluating_p, "self-evaluating?", 1, 0, 0,
	    (SCM obj),
	    "Return #t for objects which Guile considers self-evaluating")
#define FUNC_NAME s_scm_self_evaluating_p
{
  switch (SCM_ITAG3 (obj))
    {
    case scm_tc3_int_1:
    case scm_tc3_int_2:
      /* inum */
      return SCM_BOOL_T;
    case scm_tc3_imm24:
	/* characters, booleans, other immediates */
      return scm_from_bool (!scm_is_null (obj));
    case scm_tc3_cons:
      switch (SCM_TYP7 (obj))
	{
	case scm_tcs_closures:
	case scm_tc7_vector:
	case scm_tc7_wvect:
	case scm_tc7_number:
	case scm_tc7_string:
	case scm_tc7_smob:
	case scm_tc7_cclo:
	case scm_tc7_pws:
	case scm_tcs_subrs:
	case scm_tcs_struct:
	  return SCM_BOOL_T;
	default:
	  return SCM_BOOL_F;
	}
    }
  SCM_MISC_ERROR ("Internal error: Object ~S has unknown type",
		  scm_list_1 (obj));
  return SCM_UNSPECIFIED; /* never reached */
}
#undef FUNC_NAME

void
scm_init_evalext ()
{
#include "libguile/evalext.x"
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* classes: h_files */

#ifndef SCM_EVALEXT_H
#define SCM_EVALEXT_H

/* Copyright (C) 1998,1999,2000, 2003, 2006 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"

SCM_API SCM scm_defined_p (SCM sym, SCM env);
SCM_API SCM scm_self_evaluating_p (SCM obj);
SCM_API void scm_init_evalext (void);

#if (SCM_ENABLE_DEPRECATED == 1)

#define scm_definedp scm_defined_p

#endif

#endif  /* SCM_EVALEXT_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* extensions.c - registering and loading extensions.
 *
 * Copyright (C) 2001, 2006 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <string.h>

#include "libguile/_scm.h"
#include "libguile/strings.h"
#include "libguile/gc.h"
#include "libguile/dynl.h"
#include "libguile/dynwind.h"

#include "libguile/extensions.h"

typedef struct extension_t
{
  struct extension_t *next;
  const char *lib;
  const char *init;
  void (*func)(void *);
  void *data;
} extension_t;

static extension_t *registered_extensions;

/* Register a LIB/INIT pair for use by `scm_load_extension'.  LIB is
   allowed to be NULL and then only INIT is used to identify the
   registered entry.  This is useful when you don't know the library
   name (which isn't really relevant anyway in a completely linked
   program) and you are sure that INIT is unique (which it must be for
   static linking).  Hmm, given this reasoning, what use is LIB
   anyway?
*/

void
scm_c_register_extension (const char *lib, const char *init,
			  void (*func) (void *), void *data)
{
  extension_t *ext = scm_malloc (sizeof(extension_t));
  if (lib)
    ext->lib = scm_strdup (lib);
  else
    ext->lib = NULL;
  ext->init = scm_strdup (init);
  ext->func = func;
  ext->data = data;

  ext->next = registered_extensions;
  registered_extensions = ext;
}

static void
load_extension (SCM lib, SCM init)
{
  /* Search the registry. */
  if (registered_extensions != NULL)
    {
      extension_t *ext;
      char *clib, *cinit;
      int found = 0;

      scm_dynwind_begin (0);

      clib = scm_to_locale_string (lib);
      scm_dynwind_free (clib);
      cinit = scm_to_locale_string (init);
      scm_dynwind_free (cinit);

      for (ext = registered_extensions; ext; ext = ext->next)
	if ((ext->lib == NULL || !strcmp (ext->lib, clib))
	    && !strcmp (ext->init, cinit))
	  {
	    ext->func (ext->data);
            found = 1;
	    break;
	  }

      scm_dynwind_end ();

      if (found)
        return;
    }

  /* Dynamically link the library. */
  scm_dynamic_call (init, scm_dynamic_link (lib));
}

void
scm_c_load_extension (const char *lib, const char *init)
{
  load_extension (scm_from_locale_string (lib), scm_from_locale_string (init));
}

SCM_DEFINE (scm_load_extension, "load-extension", 2, 0, 0,
	    (SCM lib, SCM init),
	    "Load and initialize the extension designated by LIB and INIT.\n"
	    "When there is no pre-registered function for LIB/INIT, this is\n"
	    "equivalent to\n"
	    "\n"
	    "@lisp\n"
	    "(dynamic-call INIT (dynamic-link LIB))\n"
	    "@end lisp\n"
	    "\n"
	    "When there is a pre-registered function, that function is called\n"
	    "instead.\n"
	    "\n"
	    "Normally, there is no pre-registered function.  This option exists\n"
	    "only for situations where dynamic linking is unavailable or unwanted.\n"
	    "In that case, you would statically link your program with the desired\n"
	    "library, and register its init function right after Guile has been\n"
	    "initialized.\n"
	    "\n"
	    "LIB should be a string denoting a shared library without any file type\n"
	    "suffix such as \".so\".  The suffix is provided automatically.  It\n"
	    "should also not contain any directory components.  Libraries that\n"
	    "implement Guile Extensions should be put into the normal locations for\n"
	    "shared libraries.  We recommend to use the naming convention\n"
	    "libguile-bla-blum for a extension related to a module `(bla blum)'.\n"
	    "\n"
	    "The normal way for a extension to be used is to write a small Scheme\n"
	    "file that defines a module, and to load the extension into this\n"
	    "module.  When the module is auto-loaded, the extension is loaded as\n"
	    "well.  For example,\n"
	    "\n"
	    "@lisp\n"
	    "(define-module (bla blum))\n"
	    "\n"
	    "(load-extension \"libguile-bla-blum\" \"bla_init_blum\")\n"
	    "@end lisp")
#define FUNC_NAME s_scm_load_extension
{
  load_extension (lib, init);
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

void
scm_init_extensions ()
{
  registered_extensions = NULL;
#include "libguile/extensions.x"
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* classes: h_files */

#ifndef SCM_EXTENSIONS_H
#define SCM_EXTENSIONS_H

/* Copyright (C) 2001, 2006 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"

SCM_API void scm_c_register_extension (const char *lib, const char *init,
				       void (*func) (void *), void *data);

SCM_API void scm_c_load_extension (const char *lib, const char *init);
SCM_API SCM scm_load_extension (SCM lib, SCM init);

SCM_API void scm_init_extensions (void);

#endif  /* SCM_EXTENSIONS_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* Copyright (C) 1995,1996,1998,1999,2000,2001,2002, 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#ifdef HAVE_STRING_H
#include <string.h>
#endif

#include "libguile/_scm.h"
#include "libguile/root.h"
#include "libguile/strings.h"
#include "libguile/validate.h"
#include "libguile/fluids.h"

#include "libguile/feature.h"

static SCM progargs_fluid;
static SCM features_var;

void
scm_add_feature (const char *str)
{
  SCM old = SCM_VARIABLE_REF (features_var);
  SCM new = scm_cons (scm_from_locale_symbol (str), old);
  SCM_VARIABLE_SET (features_var, new);
}

SCM_DEFINE (scm_program_arguments, "program-arguments", 0, 0, 0,
	    (),
	    "@deffnx {Scheme Procedure} command-line\n"
	    "Return the list of command line arguments passed to Guile, as a list of\n"
	    "strings.  The list includes the invoked program name, which is usually\n"
	    "@code{\"guile\"}, but excludes switches and parameters for command line\n"
	    "options like @code{-e} and @code{-l}.")
#define FUNC_NAME s_scm_program_arguments
{
  return scm_fluid_ref (progargs_fluid);
}
#undef FUNC_NAME

/* Set the value returned by program-arguments, given ARGC and ARGV.

   If FIRST is non-zero, make it the first element; we do this in
   situations where other code (like getopt) has parsed out a few
   arguments, but we still want the script name to be the first
   element.  */
void
scm_set_program_arguments (int argc, char **argv, char *first)
{
  SCM args = scm_makfromstrs (argc, argv);
  if (first)
    args = scm_cons (scm_from_locale_string (first), args);
  scm_fluid_set_x (progargs_fluid, args);
}

SCM_DEFINE (scm_set_program_arguments_scm, "set-program-arguments", 1, 0, 0,
	    (SCM lst),
	    "Set the command line arguments to be returned by\n"
	    "@code{program-arguments} (and @code{command-line}).  @var{lst}\n"
	    "should be a list of strings, the first of which is the program\n"
	    "name (either a script name, or just @code{\"guile\"}).\n"
	    "\n"
	    "Program arguments are held in a fluid and therefore have a\n"
	    "separate value in each Guile thread.  Neither the list nor the\n"
	    "strings within it are copied, so should not be modified later.")
#define FUNC_NAME s_scm_set_program_arguments_scm
{
  return scm_fluid_set_x (progargs_fluid, lst);
}
#undef FUNC_NAME

void
scm_init_feature()
{
  progargs_fluid = scm_permanent_object (scm_make_fluid ());

  features_var = scm_c_define ("*features*", SCM_EOL);
#ifndef _Windows
  scm_add_feature("system");
#endif
#ifdef vms
  scm_add_feature(s_ed);
#endif
#ifdef SICP
  scm_add_feature("sicp");
#endif
#ifndef GO32
  scm_add_feature("char-ready?");
#endif
#ifndef CHEAP_CONTINUATIONS
  scm_add_feature ("full-continuation");
#endif
#if SCM_USE_PTHREAD_THREADS
  scm_add_feature ("threads");
#endif

  scm_c_define ("char-code-limit", scm_from_int (SCM_CHAR_CODE_LIMIT));

#include "libguile/feature.x"
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* classes: h_files */

#ifndef SCM_FEATURE_H
#define SCM_FEATURE_H

/* Copyright (C) 1995,1996,1999,2000,2001, 2006, 2007 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"

SCM_API void scm_add_feature (const char* str);
SCM_API SCM scm_program_arguments (void);
SCM_API void scm_set_program_arguments (int argc, char **argv, char *first);
SCM_API SCM scm_set_program_arguments_scm (SCM lst);
SCM_API void scm_init_feature (void);

#endif  /* SCM_FEATURE_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* Copyright (C) 1996,1997,1998,1999,2000,2001, 2002, 2004, 2006, 2008 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/* See stime.c for comments on why _POSIX_C_SOURCE is not always defined. */
#define _LARGEFILE64_SOURCE      /* ask for stat64 etc */
#ifdef __hpux
#define _POSIX_C_SOURCE 199506L  /* for readdir_r */
#endif
#if defined(__INTERIX) && !defined(_REENTRANT)
# define _REENTRANT   /* ask Interix for readdir_r prototype */
#endif

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

/* This blob per the Autoconf manual (under "Particular Functions"), updated
   to match that of Gnulib.  */
#ifndef alloca
# if HAVE_ALLOCA_H
#  include <alloca.h>
# elif defined __GNUC__
#  define alloca __builtin_alloca
# elif defined _AIX
#  define alloca __alloca
# elif defined _MSC_VER
#  include <malloc.h>
#  define alloca _alloca
# else
#  include <stddef.h>
#  ifdef  __cplusplus
extern "C"
#  endif
void *alloca (size_t);
# endif
#endif

#include <stdio.h>
#include <errno.h>

#include "libguile/_scm.h"
#include "libguile/smob.h"
#include "libguile/feature.h"
#include "libguile/fports.h"
#include "libguile/private-gc.h"  /* for SCM_MAX */
#include "libguile/iselect.h"
#include "libguile/strings.h"
#include "libguile/vectors.h"
#include "libguile/lang.h"
#include "libguile/dynwind.h"

#include "libguile/validate.h"
#include "libguile/filesys.h"

#ifdef HAVE_IO_H
#include <io.h>
#endif

#ifdef HAVE_DIRECT_H
#include <direct.h>
#endif

#ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef LIBC_H_WITH_UNISTD_H
#include <libc.h>
#endif

#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif

#ifdef HAVE_STRING_H
#include <string.h>
#endif

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#ifdef HAVE_PWD_H
#include <pwd.h>
#endif

#if defined (__MINGW32__) || defined (_MSC_VER) || defined (__BORLANDC__)
# include "win32-dirent.h"
# define NAMLEN(dirent) strlen((dirent)->d_name)
/* The following bits are per AC_HEADER_DIRENT doco in the autoconf manual */
#elif HAVE_DIRENT_H
# include <dirent.h>
# define NAMLEN(dirent) strlen((dirent)->d_name)
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# if HAVE_SYS_NDIR_H
#  include <sys/ndir.h>
# endif
# if HAVE_SYS_DIR_H
#  include <sys/dir.h>
# endif
# if HAVE_NDIR_H
#  include <ndir.h>
# endif
#endif

/* Ultrix has S_IFSOCK, but no S_ISSOCK.  Ipe!  */
#if defined (S_IFSOCK) && ! defined (S_ISSOCK)
#define S_ISSOCK(mode) (((mode) & S_IFMT) == S_IFSOCK)
#endif

/* The MinGW gcc does not define the S_ISSOCK macro. Any other native Windows
   compiler like BorlandC or MSVC has none of these macros defined. */
#ifdef __MINGW32__

# ifdef _S_IFIFO
#  undef _S_IFIFO
# endif
# ifdef _S_IFCHR
#  undef _S_IFCHR
# endif
# ifdef _S_IFBLK
#  undef _S_IFBLK
# endif
# ifdef _S_IFDIR
#  undef _S_IFDIR
# endif
# ifdef _S_IFREG
#  undef _S_IFREG
# endif
# ifdef _S_IFSOCK
#  undef _S_IFSOCK
# endif

# define _S_IFIFO        0x1000  /* FIFO */
# define _S_IFCHR        0x2000  /* Character */
# define _S_IFBLK        0x3000  /* Block */
# define _S_IFDIR        0x4000  /* Directory */
# define _S_IFREG        0x8000  /* Regular */
# define _S_IFSOCK       0xC000  /* Socket */

# ifdef S_ISBLK
#  undef S_ISBLK
# endif
# ifdef S_ISFIFO
#  undef S_ISFIFO
# endif
# ifdef S_ISCHR
#  undef S_ISCHR
# endif
# ifdef S_ISDIR
#  undef S_ISDIR
# endif
# ifdef S_ISREG
#  undef S_ISREG
# endif
# ifdef S_ISSOCK
#  undef S_ISSOCK
# endif

# define S_ISBLK(mode)  (((mode) & _S_IFMT) == _S_IFBLK)
# define S_ISFIFO(mode) (((mode) & _S_IFMT) == _S_IFIFO)
# define S_ISCHR(mode)  (((mode) & _S_IFMT) == _S_IFCHR)
# define S_ISDIR(mode)  (((mode) & _S_IFMT) == _S_IFDIR)
# define S_ISREG(mode)  (((mode) & _S_IFMT) == _S_IFREG)
# define S_ISSOCK(mode) (((mode) & _S_IFMT) == _S_IFSOCK)

#endif /* __MINGW32__ */

/* Some more definitions for the native Windows port. */
#ifdef __MINGW32__
# define mkdir(path, mode) mkdir (path)
# define fsync(fd) _commit (fd)
# define fchmod(fd, mode) (-1)
#endif /* __MINGW32__ */

/* dirfd() returns the file descriptor underlying a "DIR*" directory stream.
   Found on MacOS X for instance.  The following definition is for Solaris
   10, it's probably not right elsewhere, but that's ok, it shouldn't be
   used elsewhere.  Crib note: If we need more then gnulib has a dirfd.m4
   figuring out how to get the fd (dirfd function, dirfd macro, dd_fd field,
   or d_fd field).  */
#ifndef dirfd
#define dirfd(dirstream) ((dirstream)->dd_fd)
#endif

/* Two helper macros for an often used pattern */

#define STRING_SYSCALL(str,cstr,code)        \
  do {                                       \
    int eno;                                 \
    char *cstr = scm_to_locale_string (str); \
    SCM_SYSCALL (code);                      \
    eno = errno; free (cstr); errno = eno;   \
  } while (0)

#define STRING2_SYSCALL(str1,cstr1,str2,cstr2,code)  \
  do {                                               \
    int eno;                                         \
    char *cstr1, *cstr2;                             \
    scm_dynwind_begin (0);                             \
    cstr1 = scm_to_locale_string (str1);             \
    scm_dynwind_free (cstr1);                          \
    cstr2 = scm_to_locale_string (str2);             \
    scm_dynwind_free (cstr2);                          \
    SCM_SYSCALL (code);                              \
    eno = errno; scm_dynwind_end (); errno = eno;      \
  } while (0)

/* {Permissions}
 */

#ifdef HAVE_CHOWN
SCM_DEFINE (scm_chown, "chown", 3, 0, 0,
            (SCM object, SCM owner, SCM group),
	    "Change the ownership and group of the file referred to by @var{object} to\n"
	    "the integer values @var{owner} and @var{group}.  @var{object} can be\n"
	    "a string containing a file name or, if the platform\n"
	    "supports fchown, a port or integer file descriptor\n"
	    "which is open on the file.  The return value\n"
	    "is unspecified.\n\n"
	    "If @var{object} is a symbolic link, either the\n"
	    "ownership of the link or the ownership of the referenced file will be\n"
	    "changed depending on the operating system (lchown is\n"
	    "unsupported at present).  If @var{owner} or @var{group} is specified\n"
	    "as @code{-1}, then that ID is not changed.")
#define FUNC_NAME s_scm_chown
{
  int rv;

  object = SCM_COERCE_OUTPORT (object);

#ifdef HAVE_FCHOWN
  if (scm_is_integer (object) || (SCM_OPFPORTP (object)))
    {
      int fdes = (SCM_OPFPORTP (object)?
		  SCM_FPORT_FDES (object) : scm_to_int (object));

      SCM_SYSCALL (rv = fchown (fdes, scm_to_int (owner), scm_to_int (group)));
    }
  else
#endif
    {
      STRING_SYSCALL (object, c_object,
		      rv = chown (c_object,
				  scm_to_int (owner), scm_to_int (group)));
    }
  if (rv == -1)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif /* HAVE_CHOWN */

SCM_DEFINE (scm_chmod, "chmod", 2, 0, 0,
            (SCM object, SCM mode),
	    "Changes the permissions of the file referred to by @var{obj}.\n"
	    "@var{obj} can be a string containing a file name or a port or integer file\n"
	    "descriptor which is open on a file (in which case @code{fchmod} is used\n"
	    "as the underlying system call).\n"
	    "@var{mode} specifies\n"
	    "the new permissions as a decimal number, e.g., @code{(chmod \"foo\" #o755)}.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_chmod
{
  int rv;
  int fdes;

  object = SCM_COERCE_OUTPORT (object);

  if (scm_is_integer (object) || SCM_OPFPORTP (object))
    {
      if (scm_is_integer (object))
	fdes = scm_to_int (object);
      else
	fdes = SCM_FPORT_FDES (object);
      SCM_SYSCALL (rv = fchmod (fdes, scm_to_int (mode)));
    }
  else
    {
      STRING_SYSCALL (object, c_object,
		      rv = chmod (c_object, scm_to_int (mode)));
    }
  if (rv == -1)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

SCM_DEFINE (scm_umask, "umask", 0, 1, 0,
            (SCM mode),
	    "If @var{mode} is omitted, returns a decimal number representing the current\n"
	    "file creation mask.  Otherwise the file creation mask is set to\n"
	    "@var{mode} and the previous value is returned.\n\n"
	    "E.g., @code{(umask #o022)} sets the mask to octal 22, decimal 18.")
#define FUNC_NAME s_scm_umask
{
  mode_t mask;
  if (SCM_UNBNDP (mode))
    {
      mask = umask (0);
      umask (mask);
    }
  else
    {
      mask = umask (scm_to_uint (mode));
    }
  return scm_from_uint (mask);
}
#undef FUNC_NAME

SCM_DEFINE (scm_open_fdes, "open-fdes", 2, 1, 0,
            (SCM path, SCM flags, SCM mode),
	    "Similar to @code{open} but return a file descriptor instead of\n"
	    "a port.")
#define FUNC_NAME s_scm_open_fdes
{
  int fd;
  int iflags;
  int imode;

  iflags = SCM_NUM2INT (2, flags);
  imode = SCM_NUM2INT_DEF (3, mode, 0666);
  STRING_SYSCALL (path, c_path, fd = open_or_open64 (c_path, iflags, imode));
  if (fd == -1)
    SCM_SYSERROR;
  return scm_from_int (fd);
}
#undef FUNC_NAME

SCM_DEFINE (scm_open, "open", 2, 1, 0,
            (SCM path, SCM flags, SCM mode),
	    "Open the file named by @var{path} for reading and/or writing.\n"
	    "@var{flags} is an integer specifying how the file should be opened.\n"
	    "@var{mode} is an integer specifying the permission bits of the file, if\n"
	    "it needs to be created, before the umask is applied.  The default is 666\n"
	    "(Unix itself has no default).\n\n"
	    "@var{flags} can be constructed by combining variables using @code{logior}.\n"
	    "Basic flags are:\n\n"
	    "@defvar O_RDONLY\n"
	    "Open the file read-only.\n"
	    "@end defvar\n"
	    "@defvar O_WRONLY\n"
	    "Open the file write-only.\n"
	    "@end defvar\n"
	    "@defvar O_RDWR\n"
	    "Open the file read/write.\n"
	    "@end defvar\n"
	    "@defvar O_APPEND\n"
	    "Append to the file instead of truncating.\n"
	    "@end defvar\n"
	    "@defvar O_CREAT\n"
	    "Create the file if it does not already exist.\n"
	    "@end defvar\n\n"
	    "See the Unix documentation of the @code{open} system call\n"
	    "for additional flags.")
#define FUNC_NAME s_scm_open
{
  SCM newpt;
  char *port_mode;
  int fd;
  int iflags;

  fd = scm_to_int (scm_open_fdes (path, flags, mode));
  iflags = SCM_NUM2INT (2, flags);
  if (iflags & O_RDWR)
    {
      if (iflags & O_APPEND)
	port_mode = "a+";
      else if (iflags & O_CREAT)
	port_mode = "w+";
      else
	port_mode = "r+";
    }
  else {
    if (iflags & O_APPEND)
      port_mode = "a";
    else if (iflags & O_WRONLY)
      port_mode = "w";
    else
      port_mode = "r";
  }
  newpt = scm_fdes_to_port (fd, port_mode, path);
  return newpt;
}
#undef FUNC_NAME

SCM_DEFINE (scm_close, "close", 1, 0, 0,
            (SCM fd_or_port),
	    "Similar to close-port (@pxref{Closing, close-port}),\n"
	    "but also works on file descriptors.  A side\n"
	    "effect of closing a file descriptor is that any ports using that file\n"
	    "descriptor are moved to a different file descriptor and have\n"
	    "their revealed counts set to zero.")
#define FUNC_NAME s_scm_close
{
  int rv;
  int fd;

  fd_or_port = SCM_COERCE_OUTPORT (fd_or_port);

  if (SCM_PORTP (fd_or_port))
    return scm_close_port (fd_or_port);
  fd = scm_to_int (fd_or_port);
  scm_evict_ports (fd);		/* see scsh manual.  */
  SCM_SYSCALL (rv = close (fd));
  /* following scsh, closing an already closed file descriptor is
     not an error.  */
  if (rv < 0 && errno != EBADF)
    SCM_SYSERROR;
  return scm_from_bool (rv >= 0);
}
#undef FUNC_NAME

SCM_DEFINE (scm_close_fdes, "close-fdes", 1, 0, 0,
            (SCM fd),
	    "A simple wrapper for the @code{close} system call.\n"
	    "Close file descriptor @var{fd}, which must be an integer.\n"
	    "Unlike close (@pxref{Ports and File Descriptors, close}),\n"
	    "the file descriptor will be closed even if a port is using it.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_close_fdes
{
  int c_fd;
  int rv;

  c_fd = scm_to_int (fd);
  SCM_SYSCALL (rv = close (c_fd));
  if (rv < 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

/* {Files}
 */

SCM_SYMBOL (scm_sym_regular, "regular");
SCM_SYMBOL (scm_sym_directory, "directory");
#ifdef S_ISLNK
SCM_SYMBOL (scm_sym_symlink, "symlink");
#endif
SCM_SYMBOL (scm_sym_block_special, "block-special");
SCM_SYMBOL (scm_sym_char_special, "char-special");
SCM_SYMBOL (scm_sym_fifo, "fifo");
SCM_SYMBOL (scm_sym_sock, "socket");
SCM_SYMBOL (scm_sym_unknown, "unknown");

static SCM
scm_stat2scm (struct stat_or_stat64 *stat_temp)
{
  SCM ans = scm_c_make_vector (15, SCM_UNSPECIFIED);

  SCM_SIMPLE_VECTOR_SET(ans, 0, scm_from_ulong (stat_temp->st_dev));
  SCM_SIMPLE_VECTOR_SET(ans, 1, scm_from_ino_t_or_ino64_t (stat_temp->st_ino));
  SCM_SIMPLE_VECTOR_SET(ans, 2, scm_from_ulong (stat_temp->st_mode));
  SCM_SIMPLE_VECTOR_SET(ans, 3, scm_from_ulong (stat_temp->st_nlink));
  SCM_SIMPLE_VECTOR_SET(ans, 4, scm_from_ulong (stat_temp->st_uid));
  SCM_SIMPLE_VECTOR_SET(ans, 5, scm_from_ulong (stat_temp->st_gid));
#ifdef HAVE_STRUCT_STAT_ST_RDEV
  SCM_SIMPLE_VECTOR_SET(ans, 6, scm_from_ulong (stat_temp->st_rdev));
#else
  SCM_SIMPLE_VECTOR_SET(ans, 6, SCM_BOOL_F);
#endif
  SCM_SIMPLE_VECTOR_SET(ans, 7, scm_from_off_t_or_off64_t (stat_temp->st_size));
  SCM_SIMPLE_VECTOR_SET(ans, 8, scm_from_ulong (stat_temp->st_atime));
  SCM_SIMPLE_VECTOR_SET(ans, 9, scm_from_ulong (stat_temp->st_mtime));
  SCM_SIMPLE_VECTOR_SET(ans, 10, scm_from_ulong (stat_temp->st_ctime));
#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
  SCM_SIMPLE_VECTOR_SET(ans, 11, scm_from_ulong (stat_temp->st_blksize));
#else
  SCM_SIMPLE_VECTOR_SET(ans, 11, scm_from_ulong (4096L));
#endif
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
  SCM_SIMPLE_VECTOR_SET(ans, 12, scm_from_blkcnt_t_or_blkcnt64_t (stat_temp->st_blocks));
#else
  SCM_SIMPLE_VECTOR_SET(ans, 12, SCM_BOOL_F);
#endif
  {
    int mode = stat_temp->st_mode;

    if (S_ISREG (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_regular);
    else if (S_ISDIR (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_directory);
#ifdef S_ISLNK
    /* systems without symlinks probably don't have S_ISLNK */
    else if (S_ISLNK (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_symlink);
#endif
    else if (S_ISBLK (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_block_special);
    else if (S_ISCHR (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_char_special);
    else if (S_ISFIFO (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_fifo);
#ifdef S_ISSOCK
    else if (S_ISSOCK (mode))
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_sock);
#endif
    else
      SCM_SIMPLE_VECTOR_SET(ans, 13, scm_sym_unknown);

    SCM_SIMPLE_VECTOR_SET(ans, 14, scm_from_int ((~S_IFMT) & mode));

    /* the layout of the bits in ve[14] is intended to be portable.
       If there are systems that don't follow the usual convention,
       the following could be used:

       tmp = 0;
       if (S_ISUID & mode) tmp += 1;
       tmp <<= 1;
       if (S_IRGRP & mode) tmp += 1;
       tmp <<= 1;
       if (S_ISVTX & mode) tmp += 1;
       tmp <<= 1;
       if (S_IRUSR & mode) tmp += 1;
       tmp <<= 1;
       if (S_IWUSR & mode) tmp += 1;
       tmp <<= 1;
       if (S_IXUSR & mode) tmp += 1;
       tmp <<= 1;
       if (S_IWGRP & mode) tmp += 1;
       tmp <<= 1;
       if (S_IXGRP & mode) tmp += 1;
       tmp <<= 1;
       if (S_IROTH & mode) tmp += 1;
       tmp <<= 1;
       if (S_IWOTH & mode) tmp += 1;
       tmp <<= 1;
       if (S_IXOTH & mode) tmp += 1;

       SCM_SIMPLE_VECTOR_SET(ans, 14, scm_from_int (tmp));

       */
  }

  return ans;
}

#ifdef __MINGW32__
/*
 * Try getting the appropiate stat buffer for a given file descriptor
 * under Windows. It differentiates between file, pipe and socket
 * descriptors.
 */
static int fstat_Win32 (int fdes, struct stat *buf)
{
  int error, optlen = sizeof (int);

  memset (buf, 0, sizeof (struct stat));

  /* Is this a socket ? */
  if (getsockopt (fdes, SOL_SOCKET, SO_ERROR, (void *) &error, &optlen) >= 0)
    {
      buf->st_mode = _S_IFSOCK | _S_IREAD | _S_IWRITE | _S_IEXEC;
      buf->st_nlink = 1;
      buf->st_atime = buf->st_ctime = buf->st_mtime = time (NULL);
      return 0;
    }
  /* Maybe a regular file or pipe ? */
  return fstat (fdes, buf);
}
#endif /* __MINGW32__ */

SCM_DEFINE (scm_stat, "stat", 1, 0, 0,
            (SCM object),
	    "Return an object containing various information about the file\n"
	    "determined by @var{obj}.  @var{obj} can be a string containing\n"
	    "a file name or a port or integer file descriptor which is open\n"
	    "on a file (in which case @code{fstat} is used as the underlying\n"
	    "system call).\n"
	    "\n"
	    "The object returned by @code{stat} can be passed as a single\n"
	    "parameter to the following procedures, all of which return\n"
	    "integers:\n"
	    "\n"
	    "@table @code\n"
	    "@item stat:dev\n"
	    "The device containing the file.\n"
	    "@item stat:ino\n"
	    "The file serial number, which distinguishes this file from all\n"
	    "other files on the same device.\n"
	    "@item stat:mode\n"
	    "The mode of the file.  This includes file type information and\n"
	    "the file permission bits.  See @code{stat:type} and\n"
	    "@code{stat:perms} below.\n"
	    "@item stat:nlink\n"
	    "The number of hard links to the file.\n"
	    "@item stat:uid\n"
	    "The user ID of the file's owner.\n"
	    "@item stat:gid\n"
	    "The group ID of the file.\n"
	    "@item stat:rdev\n"
	    "Device ID; this entry is defined only for character or block\n"
	    "special files.\n"
	    "@item stat:size\n"
	    "The size of a regular file in bytes.\n"
	    "@item stat:atime\n"
	    "The last access time for the file.\n"
	    "@item stat:mtime\n"
	    "The last modification time for the file.\n"
	    "@item stat:ctime\n"
	    "The last modification time for the attributes of the file.\n"
	    "@item stat:blksize\n"
	    "The optimal block size for reading or writing the file, in\n"
	    "bytes.\n"
	    "@item stat:blocks\n"
	    "The amount of disk space that the file occupies measured in\n"
	    "units of 512 byte blocks.\n"
	    "@end table\n"
	    "\n"
	    "In addition, the following procedures return the information\n"
	    "from stat:mode in a more convenient form:\n"
	    "\n"
	    "@table @code\n"
	    "@item stat:type\n"
	    "A symbol representing the type of file.  Possible values are\n"
	    "regular, directory, symlink, block-special, char-special, fifo,\n"
	    "socket and unknown\n"
	    "@item stat:perms\n"
	    "An integer representing the access permission bits.\n"
	    "@end table")
#define FUNC_NAME s_scm_stat
{
  int rv;
  int fdes;
  struct stat_or_stat64 stat_temp;

  if (scm_is_integer (object))
    {
#ifdef __MINGW32__
      SCM_SYSCALL (rv = fstat_Win32 (scm_to_int (object), &stat_temp));
#else
      SCM_SYSCALL (rv = fstat_or_fstat64 (scm_to_int (object), &stat_temp));
#endif
    }
  else if (scm_is_string (object))
    {
      char *file = scm_to_locale_string (object);
#ifdef __MINGW32__
      char *p;
      p = file + strlen (file) - 1;
      while (p > file && (*p == '/' || *p == '\\'))
	*p-- = '\0';
#endif
      SCM_SYSCALL (rv = stat_or_stat64 (file, &stat_temp));
      free (file);
    }
  else
    {
      object = SCM_COERCE_OUTPORT (object);
      SCM_VALIDATE_OPFPORT (1, object);
      fdes = SCM_FPORT_FDES (object);
#ifdef __MINGW32__
      SCM_SYSCALL (rv = fstat_Win32 (fdes, &stat_temp));
#else
      SCM_SYSCALL (rv = fstat_or_fstat64 (fdes, &stat_temp));
#endif
    }

  if (rv == -1)
    {
      int en = errno;

      SCM_SYSERROR_MSG ("~A: ~S",
			scm_list_2 (scm_strerror (scm_from_int (en)),
				    object),
			en);
    }
  return scm_stat2scm (&stat_temp);
}
#undef FUNC_NAME

/* {Modifying Directories}
 */

#ifdef HAVE_LINK
SCM_DEFINE (scm_link, "link", 2, 0, 0,
            (SCM oldpath, SCM newpath),
	    "Creates a new name @var{newpath} in the file system for the\n"
	    "file named by @var{oldpath}.  If @var{oldpath} is a symbolic\n"
	    "link, the link may or may not be followed depending on the\n"
	    "system.")
#define FUNC_NAME s_scm_link
{
  int val;

  STRING2_SYSCALL (oldpath, c_oldpath,
		   newpath, c_newpath,
		   val = link (c_oldpath, c_newpath));
  if (val != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif /* HAVE_LINK */

#ifdef HAVE_RENAME
#define my_rename rename
#else
static int
my_rename (const char *oldname, const char *newname)
{
  int rv;

  SCM_SYSCALL (rv = link (oldname, newname));
  if (rv == 0)
    {
      SCM_SYSCALL (rv = unlink (oldname));
      if (rv != 0)
	/* unlink failed.  remove new name */
	SCM_SYSCALL (unlink (newname));
    }
  return rv;
}
#endif

SCM_DEFINE (scm_rename, "rename-file", 2, 0, 0,
            (SCM oldname, SCM newname),
	    "Renames the file specified by @var{oldname} to @var{newname}.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_rename
{
  int rv;

  STRING2_SYSCALL (oldname, c_oldname,
		   newname, c_newname,
		   rv = my_rename (c_oldname, c_newname));
  if (rv != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

SCM_DEFINE (scm_delete_file, "delete-file", 1, 0, 0,
           (SCM str),
	    "Deletes (or \"unlinks\") the file specified by @var{path}.")
#define FUNC_NAME s_scm_delete_file
{
  int ans;
  STRING_SYSCALL (str, c_str, ans = unlink (c_str));
  if (ans != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

#ifdef HAVE_MKDIR
SCM_DEFINE (scm_mkdir, "mkdir", 1, 1, 0,
            (SCM path, SCM mode),
	    "Create a new directory named by @var{path}.  If @var{mode} is omitted\n"
	    "then the permissions of the directory file are set using the current\n"
	    "umask.  Otherwise they are set to the decimal value specified with\n"
	    "@var{mode}.  The return value is unspecified.")
#define FUNC_NAME s_scm_mkdir
{
  int rv;
  mode_t mask;

  if (SCM_UNBNDP (mode))
    {
      mask = umask (0);
      umask (mask);
      STRING_SYSCALL (path, c_path, rv = mkdir (c_path, 0777 ^ mask));
    }
  else
    {
      STRING_SYSCALL (path, c_path, rv = mkdir (c_path, scm_to_uint (mode)));
    }
  if (rv != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif /* HAVE_MKDIR */

#ifdef HAVE_RMDIR
SCM_DEFINE (scm_rmdir, "rmdir", 1, 0, 0,
            (SCM path),
	    "Remove the existing directory named by @var{path}.  The directory must\n"
	    "be empty for this to succeed.  The return value is unspecified.")
#define FUNC_NAME s_scm_rmdir
{
  int val;

  STRING_SYSCALL (path, c_path, val = rmdir (c_path));
  if (val != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif

/* {Examining Directories}
 */

scm_t_bits scm_tc16_dir;

SCM_DEFINE (scm_directory_stream_p, "directory-stream?", 1, 0, 0,
            (SCM obj),
	    "Return a boolean indicating whether @var{object} is a directory\n"
	    "stream as returned by @code{opendir}.")
#define FUNC_NAME s_scm_directory_stream_p
{
  return scm_from_bool (SCM_DIRP (obj));
}
#undef FUNC_NAME

SCM_DEFINE (scm_opendir, "opendir", 1, 0, 0,
            (SCM dirname),
	    "Open the directory specified by @var{path} and return a directory\n"
	    "stream.")
#define FUNC_NAME s_scm_opendir
{
  DIR *ds;
  STRING_SYSCALL (dirname, c_dirname, ds = opendir (c_dirname));
  if (ds == NULL)
    SCM_SYSERROR;
  SCM_RETURN_NEWSMOB (scm_tc16_dir | SCM_DIR_FLAG_OPEN, ds);
}
#undef FUNC_NAME

/* FIXME: The glibc manual has a portability note that readdir_r may not
   null-terminate its return string.  The circumstances outlined for this
   are not clear, nor is it clear what should be done about it.  Lets use
   NAMLEN and worry about what else should be done if/when someone can
   figure it out.  */

SCM_DEFINE (scm_readdir, "readdir", 1, 0, 0,
            (SCM port),
	    "Return (as a string) the next directory entry from the directory stream\n"
	    "@var{stream}.  If there is no remaining entry to be read then the\n"
	    "end of file object is returned.")
#define FUNC_NAME s_scm_readdir
{
  struct dirent_or_dirent64 *rdent;

  SCM_VALIDATE_DIR (1, port);
  if (!SCM_DIR_OPEN_P (port))
    SCM_MISC_ERROR ("Directory ~S is not open.", scm_list_1 (port));

#if HAVE_READDIR_R
  /* As noted in the glibc manual, on various systems (such as Solaris) the
     d_name[] field is only 1 char and you're expected to size the dirent
     buffer for readdir_r based on NAME_MAX.  The SCM_MAX expressions below
     effectively give either sizeof(d_name) or NAME_MAX+1, whichever is
     bigger.

     On solaris 10 there's no NAME_MAX constant, it's necessary to use
     pathconf().  We prefer NAME_MAX though, since it should be a constant
     and will therefore save a system call.  We also prefer it since dirfd()
     is not available everywhere.

     An alternative to dirfd() would be to open() the directory and then use
     fdopendir(), if the latter is available.  That'd let us hold the fd
     somewhere in the smob, or just the dirent size calculated once.  */
  {
    struct dirent_or_dirent64 de; /* just for sizeof */
    DIR    *ds = (DIR *) SCM_CELL_WORD_1 (port);
    size_t namlen;
#ifdef NAME_MAX
    char   buf [SCM_MAX (sizeof (de),
                         sizeof (de) - sizeof (de.d_name) + NAME_MAX + 1)];
#else
    char   *buf;
    long   name_max = fpathconf (dirfd (ds), _PC_NAME_MAX);
    if (name_max == -1)
      SCM_SYSERROR;
    buf = alloca (SCM_MAX (sizeof (de),
                           sizeof (de) - sizeof (de.d_name) + name_max + 1));
#endif

    errno = 0;
    SCM_SYSCALL (readdir_r_or_readdir64_r (ds, (struct dirent_or_dirent64 *) buf, &rdent));
    if (errno != 0)
      SCM_SYSERROR;
    if (! rdent)
      return SCM_EOF_VAL;

    namlen = NAMLEN (rdent);

    return (rdent ? scm_from_locale_stringn (rdent->d_name, NAMLEN (rdent))
            : SCM_EOF_VAL);
  }
#else
  {
    SCM ret;
    scm_dynwind_begin (0);
    scm_i_dynwind_pthread_mutex_lock (&scm_i_misc_mutex);

    errno = 0;
    SCM_SYSCALL (rdent = readdir_or_readdir64 ((DIR *) SCM_CELL_WORD_1 (port)));
    if (errno != 0)
      SCM_SYSERROR;

    ret = (rdent ? scm_from_locale_stringn (rdent->d_name, NAMLEN (rdent))
           : SCM_EOF_VAL);

    scm_dynwind_end ();
    return ret;
  }
#endif
}
#undef FUNC_NAME

SCM_DEFINE (scm_rewinddir, "rewinddir", 1, 0, 0,
            (SCM port),
	    "Reset the directory port @var{stream} so that the next call to\n"
	    "@code{readdir} will return the first directory entry.")
#define FUNC_NAME s_scm_rewinddir
{
  SCM_VALIDATE_DIR (1, port);
  if (!SCM_DIR_OPEN_P (port))
    SCM_MISC_ERROR ("Directory ~S is not open.", scm_list_1 (port));

  rewinddir ((DIR *) SCM_CELL_WORD_1 (port));

  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

SCM_DEFINE (scm_closedir, "closedir", 1, 0, 0,
            (SCM port),
	    "Close the directory stream @var{stream}.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_closedir
{
  SCM_VALIDATE_DIR (1, port);

  if (SCM_DIR_OPEN_P (port))
    {
      int sts;

      SCM_SYSCALL (sts = closedir ((DIR *) SCM_CELL_WORD_1 (port)));
      if (sts != 0)
	SCM_SYSERROR;

      SCM_SET_CELL_WORD_0 (port, scm_tc16_dir);
    }

  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

static int
scm_dir_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
{
  scm_puts ("#<", port);
  if (!SCM_DIR_OPEN_P (exp))
    scm_puts ("closed: ", port);
  scm_puts ("directory stream ", port);
  scm_uintprint (SCM_CELL_WORD_1 (exp), 16, port);
  scm_putc ('>', port);
  return 1;
}

static size_t
scm_dir_free (SCM p)
{
  if (SCM_DIR_OPEN_P (p))
    closedir ((DIR *) SCM_CELL_WORD_1 (p));
  return 0;
}

/* {Navigating Directories}
 */

SCM_DEFINE (scm_chdir, "chdir", 1, 0, 0,
            (SCM str),
	    "Change the current working directory to @var{path}.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_chdir
{
  int ans;

  STRING_SYSCALL (str, c_str, ans = chdir (c_str));
  if (ans != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

#ifdef HAVE_GETCWD
SCM_DEFINE (scm_getcwd, "getcwd", 0, 0, 0,
            (),
	    "Return the name of the current working directory.")
#define FUNC_NAME s_scm_getcwd
{
  char *rv;
  size_t size = 100;
  char *wd;
  SCM result;

  wd = scm_malloc (size);
  while ((rv = getcwd (wd, size)) == 0 && errno == ERANGE)
    {
      free (wd);
      size *= 2;
      wd = scm_malloc (size);
    }
  if (rv == 0)
    {
      int save_errno = errno;
      free (wd);
      errno = save_errno;
      SCM_SYSERROR;
    }
  result = scm_from_locale_stringn (wd, strlen (wd));
  free (wd);
  return result;
}
#undef FUNC_NAME
#endif /* HAVE_GETCWD */

#ifdef HAVE_SELECT

/* check that element is a port or file descriptor.  if it's a port
   and its buffer is ready for use, add it to the ports_ready list.
   otherwise add its file descriptor to *set.  the type of list can be
   determined from pos: SCM_ARG1 for reads, SCM_ARG2 for writes,
   SCM_ARG3 for excepts.  */
static int
set_element (SELECT_TYPE *set, SCM *ports_ready, SCM element, int pos)
{
  int fd;

  if (scm_is_integer (element))
    {
      fd = scm_to_int (element);
    }
  else
    {
      int use_buf = 0;

      element = SCM_COERCE_OUTPORT (element);
      SCM_ASSERT (SCM_OPFPORTP (element), element, pos, "select");
      if (pos == SCM_ARG1)
	{
	  /* check whether port has buffered input.  */
	  scm_t_port *pt = SCM_PTAB_ENTRY (element);

	  if (pt->read_pos < pt->read_end)
	    use_buf = 1;
	}
      else if (pos == SCM_ARG2)
	{
	  /* check whether port's output buffer has room.  */
	  scm_t_port *pt = SCM_PTAB_ENTRY (element);

	  /* > 1 since writing the last byte in the buffer causes flush.  */
	  if (pt->write_end - pt->write_pos > 1)
	    use_buf = 1;
	}
      fd = use_buf ? -1 : SCM_FPORT_FDES (element);
    }
  if (fd == -1)
    *ports_ready = scm_cons (element, *ports_ready);
  else
    FD_SET (fd, set);
  return fd;
}

/* check list_or_vec, a list or vector of ports or file descriptors,
   adding each member to either the ports_ready list (if it's a port
   with a usable buffer) or to *set.  the kind of list_or_vec can be
   determined from pos: SCM_ARG1 for reads, SCM_ARG2 for writes,
   SCM_ARG3 for excepts.  */
static int
fill_select_type (SELECT_TYPE *set, SCM *ports_ready, SCM list_or_vec, int pos)
{
  int max_fd = 0;

  if (scm_is_simple_vector (list_or_vec))
    {
      int i = SCM_SIMPLE_VECTOR_LENGTH (list_or_vec);

      while (--i >= 0)
	{
	  int fd = set_element (set, ports_ready,
				SCM_SIMPLE_VECTOR_REF (list_or_vec, i), pos);

	  if (fd > max_fd)
	    max_fd = fd;
	}
    }
  else
    {
      while (!SCM_NULL_OR_NIL_P (list_or_vec))
	{
	  int fd = set_element (set, ports_ready, SCM_CAR (list_or_vec), pos);

	  if (fd > max_fd)
	    max_fd = fd;
	  list_or_vec = SCM_CDR (list_or_vec);
	}
    }

  return max_fd;
}

/* if element (a file descriptor or port) appears in *set, cons it to
   list.  return list.  */
static SCM
get_element (SELECT_TYPE *set, SCM element, SCM list)
{
  int fd;

  if (scm_is_integer (element))
    {
      fd = scm_to_int (element);
    }
  else
    {
      fd = SCM_FPORT_FDES (SCM_COERCE_OUTPORT (element));
    }
  if (FD_ISSET (fd, set))
    list = scm_cons (element, list);
  return list;
}

/* construct component of scm_select return value.
   set: pointer to set of file descriptors found by select to be ready
   ports_ready: ports ready due to buffering
   list_or_vec: original list/vector handed to scm_select.
   the return value is a list/vector of ready ports/file descriptors.
   works by finding the objects in list which correspond to members of
   *set and appending them to ports_ready.  result is converted to a
   vector if list_or_vec is a vector.  */
static SCM
retrieve_select_type (SELECT_TYPE *set, SCM ports_ready, SCM list_or_vec)
{
  SCM answer_list = ports_ready;

  if (scm_is_simple_vector (list_or_vec))
    {
      int i = SCM_SIMPLE_VECTOR_LENGTH (list_or_vec);

      while (--i >= 0)
	{
	  answer_list = get_element (set,
				     SCM_SIMPLE_VECTOR_REF (list_or_vec, i),
				     answer_list);
	}
      return scm_vector (answer_list);
    }
  else
    {
      /* list_or_vec must be a list.  */
      while (!SCM_NULL_OR_NIL_P (list_or_vec))
	{
	  answer_list = get_element (set, SCM_CAR (list_or_vec), answer_list);
	  list_or_vec = SCM_CDR (list_or_vec);
	}
      return answer_list;
    }
}

/* Static helper functions above refer to s_scm_select directly as s_select */
SCM_DEFINE (scm_select, "select", 3, 2, 0,
            (SCM reads, SCM writes, SCM excepts, SCM secs, SCM usecs),
	    "This procedure has a variety of uses: waiting for the ability\n"
	    "to provide input, accept output, or the existence of\n"
	    "exceptional conditions on a collection of ports or file\n"
	    "descriptors, or waiting for a timeout to occur.\n"
	    "It also returns if interrupted by a signal.\n\n"
	    "@var{reads}, @var{writes} and @var{excepts} can be lists or\n"
	    "vectors, with each member a port or a file descriptor.\n"
	    "The value returned is a list of three corresponding\n"
	    "lists or vectors containing only the members which meet the\n"
	    "specified requirement.  The ability of port buffers to\n"
	    "provide input or accept output is taken into account.\n"
	    "Ordering of the input lists or vectors is not preserved.\n\n"
	    "The optional arguments @var{secs} and @var{usecs} specify the\n"
	    "timeout.  Either @var{secs} can be specified alone, as\n"
	    "either an integer or a real number, or both @var{secs} and\n"
	    "@var{usecs} can be specified as integers, in which case\n"
	    "@var{usecs} is an additional timeout expressed in\n"
	    "microseconds.  If @var{secs} is omitted or is @code{#f} then\n"
	    "select will wait for as long as it takes for one of the other\n"
	    "conditions to be satisfied.\n\n"
	    "The scsh version of @code{select} differs as follows:\n"
	    "Only vectors are accepted for the first three arguments.\n"
	    "The @var{usecs} argument is not supported.\n"
	    "Multiple values are returned instead of a list.\n"
	    "Duplicates in the input vectors appear only once in output.\n"
	    "An additional @code{select!} interface is provided.")
#define FUNC_NAME s_scm_select
{
  struct timeval timeout;
  struct timeval * time_ptr;
  SELECT_TYPE read_set;
  SELECT_TYPE write_set;
  SELECT_TYPE except_set;
  int read_count;
  int write_count;
  int except_count;
  /* these lists accumulate ports which are ready due to buffering.
     their file descriptors don't need to be added to the select sets.  */
  SCM read_ports_ready = SCM_EOL;
  SCM write_ports_ready = SCM_EOL;
  int max_fd;

  if (scm_is_simple_vector (reads))
    {
      read_count = SCM_SIMPLE_VECTOR_LENGTH (reads);
    }
  else
    {
      read_count = scm_ilength (reads);
      SCM_ASSERT (read_count >= 0, reads, SCM_ARG1, FUNC_NAME);
    }
  if (scm_is_simple_vector (writes))
    {
      write_count = SCM_SIMPLE_VECTOR_LENGTH (writes);
    }
  else
    {
      write_count = scm_ilength (writes);
      SCM_ASSERT (write_count >= 0, writes, SCM_ARG2, FUNC_NAME);
    }
  if (scm_is_simple_vector (excepts))
    {
      except_count = SCM_SIMPLE_VECTOR_LENGTH (excepts);
    }
  else
    {
      except_count = scm_ilength (excepts);
      SCM_ASSERT (except_count >= 0, excepts, SCM_ARG3, FUNC_NAME);
    }

  FD_ZERO (&read_set);
  FD_ZERO (&write_set);
  FD_ZERO (&except_set);

  max_fd = fill_select_type (&read_set, &read_ports_ready, reads, SCM_ARG1);

  {
    int write_max = fill_select_type (&write_set, &write_ports_ready,
				      writes, SCM_ARG2);
    int except_max = fill_select_type (&except_set, NULL,
				       excepts, SCM_ARG3);

    if (write_max > max_fd)
      max_fd = write_max;
    if (except_max > max_fd)
      max_fd = except_max;
  }

  /* if there's a port with a ready buffer, don't block, just
     check for ready file descriptors.  */
  if (!scm_is_null (read_ports_ready) || !scm_is_null (write_ports_ready))
    {
      timeout.tv_sec = 0;
      timeout.tv_usec = 0;
      time_ptr = &timeout;
    }
  else if (SCM_UNBNDP (secs) || scm_is_false (secs))
    time_ptr = 0;
  else
    {
      if (scm_is_unsigned_integer (secs, 0, ULONG_MAX))
	{
	  timeout.tv_sec = scm_to_ulong (secs);
	  if (SCM_UNBNDP (usecs))
	    timeout.tv_usec = 0;
	  else
	    timeout.tv_usec = scm_to_long (usecs);
	}
      else
	{
	  double fl = scm_to_double (secs);

	  if (!SCM_UNBNDP (usecs))
	    SCM_WRONG_TYPE_ARG (4, secs);
	  if (fl > LONG_MAX)
	    SCM_OUT_OF_RANGE (4, secs);
	  timeout.tv_sec = (long) fl;
	  timeout.tv_usec = (long) ((fl - timeout.tv_sec) * 1000000);
	}
      time_ptr = &timeout;
    }

  {
    int rv = scm_std_select (max_fd + 1,
			     &read_set, &write_set, &except_set,
			     time_ptr);
    if (rv < 0)
      SCM_SYSERROR;
  }
  return scm_list_3 (retrieve_select_type (&read_set, read_ports_ready, reads),
		     retrieve_select_type (&write_set, write_ports_ready, writes),
		     retrieve_select_type (&except_set, SCM_EOL, excepts));
}
#undef FUNC_NAME
#endif /* HAVE_SELECT */

#ifdef HAVE_FCNTL
SCM_DEFINE (scm_fcntl, "fcntl", 2, 1, 0,
            (SCM object, SCM cmd, SCM value),
	    "Apply @var{command} to the specified file descriptor or the underlying\n"
	    "file descriptor of the specified port.  @var{value} is an optional\n"
	    "integer argument.\n\n"
	    "Values for @var{command} are:\n\n"
	    "@table @code\n"
	    "@item F_DUPFD\n"
	    "Duplicate a file descriptor\n"
	    "@item F_GETFD\n"
	    "Get flags associated with the file descriptor.\n"
	    "@item F_SETFD\n"
	    "Set flags associated with the file descriptor to @var{value}.\n"
	    "@item F_GETFL\n"
	    "Get flags associated with the open file.\n"
	    "@item F_SETFL\n"
	    "Set flags associated with the open file to @var{value}\n"
	    "@item F_GETOWN\n"
	    "Get the process ID of a socket's owner, for @code{SIGIO} signals.\n"
	    "@item F_SETOWN\n"
	    "Set the process that owns a socket to @var{value}, for @code{SIGIO} signals.\n"
	    "@item FD_CLOEXEC\n"
	    "The value used to indicate the \"close on exec\" flag with @code{F_GETFL} or\n"
	    "@code{F_SETFL}.\n"
	    "@end table")
#define FUNC_NAME s_scm_fcntl
{
  int rv;
  int fdes;
  int ivalue;

  object = SCM_COERCE_OUTPORT (object);

  if (SCM_OPFPORTP (object))
    fdes = SCM_FPORT_FDES (object);
  else
    fdes = scm_to_int (object);

  if (SCM_UNBNDP (value))
    ivalue = 0;
  else
    ivalue = scm_to_int (value);

  SCM_SYSCALL (rv = fcntl (fdes, scm_to_int (cmd), ivalue));
  if (rv == -1)
    SCM_SYSERROR;
  return scm_from_int (rv);
}
#undef FUNC_NAME
#endif /* HAVE_FCNTL */

SCM_DEFINE (scm_fsync, "fsync", 1, 0, 0,
            (SCM object),
	    "Copies any unwritten data for the specified output file descriptor to disk.\n"
	    "If @var{port/fd} is a port, its buffer is flushed before the underlying\n"
	    "file descriptor is fsync'd.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_fsync
{
  int fdes;

  object = SCM_COERCE_OUTPORT (object);

  if (SCM_OPFPORTP (object))
    {
      scm_flush (object);
      fdes = SCM_FPORT_FDES (object);
    }
  else
    fdes = scm_to_int (object);

  if (fsync (fdes) == -1)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

#ifdef HAVE_SYMLINK
SCM_DEFINE (scm_symlink, "symlink", 2, 0, 0,
            (SCM oldpath, SCM newpath),
	    "Create a symbolic link named @var{path-to} with the value (i.e., pointing to)\n"
	    "@var{path-from}.  The return value is unspecified.")
#define FUNC_NAME s_scm_symlink
{
  int val;

  STRING2_SYSCALL (oldpath, c_oldpath,
		   newpath, c_newpath,
		   val = symlink (c_oldpath, c_newpath));
  if (val != 0)
    SCM_SYSERROR;
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif /* HAVE_SYMLINK */

#ifdef HAVE_READLINK
SCM_DEFINE (scm_readlink, "readlink", 1, 0, 0,
            (SCM path),
	    "Return the value of the symbolic link named by @var{path} (a\n"
	    "string), i.e., the file that the link points to.")
#define FUNC_NAME s_scm_readlink
{
  int rv;
  int size = 100;
  char *buf;
  SCM result;
  char *c_path;

  scm_dynwind_begin (0);

  c_path = scm_to_locale_string (path);
  scm_dynwind_free (c_path);

  buf = scm_malloc (size);

  while ((rv = readlink (c_path, buf, size)) == size)
    {
      free (buf);
      size *= 2;
      buf = scm_malloc (size);
    }
  if (rv == -1)
    {
      int save_errno = errno;
      free (buf);
      errno = save_errno;
      SCM_SYSERROR;
    }
  result = scm_take_locale_stringn (buf, rv);

  scm_dynwind_end ();
  return result;
}
#undef FUNC_NAME
#endif /* HAVE_READLINK */

#ifdef HAVE_LSTAT
SCM_DEFINE (scm_lstat, "lstat", 1, 0, 0,
            (SCM str),
	    "Similar to @code{stat}, but does not follow symbolic links, i.e.,\n"
	    "it will return information about a symbolic link itself, not the\n"
	    "file it points to.  @var{path} must be a string.")
#define FUNC_NAME s_scm_lstat
{
  int rv;
  struct stat_or_stat64 stat_temp;

  STRING_SYSCALL (str, c_str, rv = lstat_or_lstat64 (c_str, &stat_temp));
  if (rv != 0)
    {
      int en = errno;

      SCM_SYSERROR_MSG ("~A: ~S",
			scm_list_2 (scm_strerror (scm_from_int (en)), str),
			en);
    }
  return scm_stat2scm (&stat_temp);
}
#undef FUNC_NAME
#endif /* HAVE_LSTAT */

SCM_DEFINE (scm_copy_file, "copy-file", 2, 0, 0,
            (SCM oldfile, SCM newfile),
	    "Copy the file specified by @var{path-from} to @var{path-to}.\n"
	    "The return value is unspecified.")
#define FUNC_NAME s_scm_copy_file
{
  char *c_oldfile, *c_newfile;
  int oldfd, newfd;
  int n, rv;
  char buf[BUFSIZ];
  struct stat_or_stat64 oldstat;

  scm_dynwind_begin (0);

  c_oldfile = scm_to_locale_string (oldfile);
  scm_dynwind_free (c_oldfile);
  c_newfile = scm_to_locale_string (newfile);
  scm_dynwind_free (c_newfile);

  oldfd = open_or_open64 (c_oldfile, O_RDONLY);
  if (oldfd == -1)
    SCM_SYSERROR;

#ifdef __MINGW32__
  SCM_SYSCALL (rv = fstat_Win32 (oldfd, &oldstat));
#else
  SCM_SYSCALL (rv = fstat_or_fstat64 (oldfd, &oldstat));
#endif
  if (rv == -1)
    goto err_close_oldfd;

  /* use POSIX flags instead of 07777?.  */
  newfd = open_or_open64 (c_newfile, O_WRONLY | O_CREAT | O_TRUNC,
                          oldstat.st_mode & 07777);
  if (newfd == -1)
    {
    err_close_oldfd:
      close (oldfd);
      SCM_SYSERROR;
    }

  while ((n = read (oldfd, buf, sizeof buf)) > 0)
    if (write (newfd, buf, n) != n)
      {
	close (oldfd);
	close (newfd);
	SCM_SYSERROR;
      }
  close (oldfd);
  if (close (newfd) == -1)
    SCM_SYSERROR;

  scm_dynwind_end ();
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

/* Filename manipulation */

SCM scm_dot_string;

SCM_DEFINE (scm_dirname, "dirname", 1, 0, 0,
            (SCM filename),
	    "Return the directory name component of the file name\n"
	    "@var{filename}. If @var{filename} does not contain a directory\n"
	    "component, @code{.} is returned.")
#define FUNC_NAME s_scm_dirname
{
  const char *s;
  long int i;
  unsigned long int len;

  SCM_VALIDATE_STRING (1, filename);

  s = scm_i_string_chars (filename);
  len = scm_i_string_length (filename);

  i = len - 1;
#ifdef __MINGW32__
  while (i >= 0 && (s[i] == '/' || s[i] == '\\')) --i;
  while (i >= 0 && (s[i] != '/' && s[i] != '\\')) --i;
  while (i >= 0 && (s[i] == '/' || s[i] == '\\')) --i;
#else
  while (i >= 0 && s[i] == '/') --i;
  while (i >= 0 && s[i] != '/') --i;
  while (i >= 0 && s[i] == '/') --i;
#endif /* ndef __MINGW32__ */
  if (i < 0)
    {
#ifdef __MINGW32__
      if (len > 0 && (s[0] == '/' || s[0] == '\\'))
#else
      if (len > 0 && s[0] == '/')
#endif /* ndef __MINGW32__ */
	return scm_c_substring (filename, 0, 1);
      else
	return scm_dot_string;
    }
  else
    return scm_c_substring (filename, 0, i + 1);
}
#undef FUNC_NAME

SCM_DEFINE (scm_basename, "basename", 1, 1, 0,
            (SCM filename, SCM suffix),
	    "Return the base name of the file name @var{filename}. The\n"
	    "base name is the file name without any directory components.\n"
	    "If @var{suffix} is provided, and is equal to the end of\n"
	    "@var{basename}, it is removed also.")
#define FUNC_NAME s_scm_basename
{
  const char *f, *s = 0;
  int i, j, len, end;

  SCM_VALIDATE_STRING (1, filename);
  f = scm_i_string_chars (filename);
  len = scm_i_string_length (filename);

  if (SCM_UNBNDP (suffix))
    j = -1;
  else
    {
      SCM_VALIDATE_STRING (2, suffix);
      s = scm_i_string_chars (suffix);
      j = scm_i_string_length (suffix) - 1;
    }
  i = len - 1;
#ifdef __MINGW32__
  while (i >= 0 && (f[i] == '/' || f[i] == '\\')) --i;
#else
  while (i >= 0 && f[i] == '/') --i;
#endif /* ndef __MINGW32__ */
  end = i;
  while (i >= 0 && j >= 0 && f[i] == s[j]) --i, --j;
  if (j == -1)
    end = i;
#ifdef __MINGW32__
  while (i >= 0 && f[i] != '/' && f[i] != '\\') --i;
#else
  while (i >= 0 && f[i] != '/') --i;
#endif /* ndef __MINGW32__ */
  if (i == end)
    {
#ifdef __MINGW32__
      if (len > 0 && (f[0] == '/' || f[0] == '\\'))
#else
      if (len > 0 && f[0] == '/')
#endif /* ndef __MINGW32__ */
	return scm_c_substring (filename, 0, 1);
      else
	return scm_dot_string;
    }
  else
    return scm_c_substring (filename, i+1, end+1);
}
#undef FUNC_NAME

void
scm_init_filesys ()
{
  scm_tc16_dir = scm_make_smob_type ("directory", 0);
  scm_set_smob_free (scm_tc16_dir, scm_dir_free);
  scm_set_smob_print (scm_tc16_dir, scm_dir_print);

  scm_dot_string = scm_permanent_object (scm_from_locale_string ("."));

#ifdef O_RDONLY
  scm_c_define ("O_RDONLY", scm_from_int (O_RDONLY));
#endif
#ifdef O_WRONLY
  scm_c_define ("O_WRONLY", scm_from_int (O_WRONLY));
#endif
#ifdef O_RDWR
  scm_c_define ("O_RDWR", scm_from_int (O_RDWR));
#endif
#ifdef O_CREAT
  scm_c_define ("O_CREAT", scm_from_int (O_CREAT));
#endif
#ifdef O_EXCL
  scm_c_define ("O_EXCL", scm_from_int (O_EXCL));
#endif
#ifdef O_NOCTTY
  scm_c_define ("O_NOCTTY", scm_from_int (O_NOCTTY));
#endif
#ifdef O_TRUNC
  scm_c_define ("O_TRUNC", scm_from_int (O_TRUNC));
#endif
#ifdef O_APPEND
  scm_c_define ("O_APPEND", scm_from_int (O_APPEND));
#endif
#ifdef O_NONBLOCK
  scm_c_define ("O_NONBLOCK", scm_from_int (O_NONBLOCK));
#endif
#ifdef O_NDELAY
  scm_c_define ("O_NDELAY", scm_from_int (O_NDELAY));
#endif
#ifdef O_SYNC
  scm_c_define ("O_SYNC", scm_from_int (O_SYNC));
#endif
#ifdef O_LARGEFILE
  scm_c_define ("O_LARGEFILE", scm_from_int (O_LARGEFILE));
#endif

#ifdef F_DUPFD
  scm_c_define ("F_DUPFD", scm_from_int (F_DUPFD));
#endif
#ifdef F_GETFD
  scm_c_define ("F_GETFD", scm_from_int (F_GETFD));
#endif
#ifdef F_SETFD
  scm_c_define ("F_SETFD", scm_from_int (F_SETFD));
#endif
#ifdef F_GETFL
  scm_c_define ("F_GETFL", scm_from_int (F_GETFL));
#endif
#ifdef F_SETFL
  scm_c_define ("F_SETFL", scm_from_int (F_SETFL));
#endif
#ifdef F_GETOWN
  scm_c_define ("F_GETOWN", scm_from_int (F_GETOWN));
#endif
#ifdef F_SETOWN
  scm_c_define ("F_SETOWN", scm_from_int (F_SETOWN));
#endif
#ifdef FD_CLOEXEC
  scm_c_define ("FD_CLOEXEC", scm_from_int (FD_CLOEXEC));
#endif

#include "libguile/filesys.x"
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* classes: h_files */

#ifndef SCM_FILESYS_H
#define SCM_FILESYS_H

/* Copyright (C) 1995,1997,1998,1999,2000,2001, 2006 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"

SCM_API scm_t_bits scm_tc16_dir;

#define SCM_DIR_FLAG_OPEN (1L << 16)

#define SCM_DIRP(x) (!SCM_IMP (x) && (SCM_TYP16 (x) == scm_tc16_dir))
#define SCM_DIR_OPEN_P(x) (SCM_CELL_WORD_0 (x) & SCM_DIR_FLAG_OPEN)

SCM_API SCM scm_chown (SCM object, SCM owner, SCM group);
SCM_API SCM scm_chmod (SCM object, SCM mode);
SCM_API SCM scm_umask (SCM mode);
SCM_API SCM scm_open_fdes (SCM path, SCM flags, SCM mode);
SCM_API SCM scm_open (SCM path, SCM flags, SCM mode);
SCM_API SCM scm_close (SCM fd_or_port);
SCM_API SCM scm_close_fdes (SCM fd);
SCM_API SCM scm_stat (SCM object);
SCM_API SCM scm_link (SCM oldpath, SCM newpath);
SCM_API SCM scm_rename (SCM oldname, SCM newname);
SCM_API SCM scm_delete_file (SCM str);
SCM_API SCM scm_mkdir (SCM path, SCM mode);
SCM_API SCM scm_rmdir (SCM path);
SCM_API SCM scm_directory_stream_p (SCM obj);
SCM_API SCM scm_opendir (SCM dirname);
SCM_API SCM scm_readdir (SCM port);
SCM_API SCM scm_rewinddir (SCM port);
SCM_API SCM scm_closedir (SCM port);
SCM_API SCM scm_chdir (SCM str);
SCM_API SCM scm_getcwd (void);
SCM_API SCM scm_select (SCM reads, SCM writes, SCM excepts, SCM secs, SCM msecs);
SCM_API SCM scm_fcntl (SCM object, SCM cmd, SCM value);
SCM_API SCM scm_fsync (SCM object);
SCM_API SCM scm_symlink (SCM oldpath, SCM newpath);
SCM_API SCM scm_readlink (SCM path);
SCM_API SCM scm_lstat (SCM str);
SCM_API SCM scm_copy_file (SCM oldfile, SCM newfile);
SCM_API SCM scm_dirname (SCM filename);
SCM_API SCM scm_basename (SCM filename, SCM suffix);

SCM_API void scm_init_filesys (void);

#endif  /* SCM_FILESYS_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* Copyright (C) 1996,1997,2000,2001, 2004, 2006, 2007, 2008 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <stdio.h>
#include <string.h>

#include "libguile/_scm.h"
#include "libguile/print.h"
#include "libguile/smob.h"
#include "libguile/dynwind.h"
#include "libguile/fluids.h"
#include "libguile/alist.h"
#include "libguile/eval.h"
#include "libguile/ports.h"
#include "libguile/deprecation.h"
#include "libguile/lang.h"
#include "libguile/validate.h"

#define FLUID_GROW 20

/* A lot of the complexity below stems from the desire to reuse fluid
   slots.  Normally, fluids should be pretty global and long-lived
   things, so that reusing their slots should not be overly critical,
   but it is the right thing to do nevertheless.  The code therefore
   puts the burdon on allocating and collection fluids and keeps
   accessing fluids lock free.  This is achieved by manipulating the
   global state of the fluid machinery mostly in single threaded
   sections.

   Reusing a fluid slot means that it must be reset to #f in all
   dynamic states.  We do this by maintaining a weak list of all
   dynamic states, which is used after a GC to do the resetting.

   Also, the fluid vectors in the dynamic states need to grow from
   time to time when more fluids are created.  We do this in a single
   threaded section so that threads do not need to lock when accessing
   a fluid in the normal way.
*/

static scm_i_pthread_mutex_t fluid_admin_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER;

/* Protected by fluid_admin_mutex, but also accessed during GC.  See
   next_fluid_num for a discussion of this.
 */
static size_t allocated_fluids_len = 0;
static size_t allocated_fluids_num = 0;
static char *allocated_fluids = NULL;

static scm_t_bits tc16_fluid;

#define IS_FLUID(x)         SCM_SMOB_PREDICATE(tc16_fluid, (x))
#define FLUID_NUM(x)        ((size_t)SCM_SMOB_DATA(x))
#define FLUID_NEXT(x)       SCM_SMOB_OBJECT_2(x)
#define FLUID_NEXT_LOC(x)       SCM_SMOB_OBJECT_2_LOC(x)
#define SET_FLUID_NEXT(x,y) SCM_SET_SMOB_OBJECT_2((x), (y))

static scm_t_bits tc16_dynamic_state;

#define IS_DYNAMIC_STATE(x)        SCM_SMOB_PREDICATE(tc16_dynamic_state, (x))
#define DYNAMIC_STATE_FLUIDS(x)        SCM_SMOB_OBJECT(x)
#define SET_DYNAMIC_STATE_FLUIDS(x, y) SCM_SET_SMOB_OBJECT((x), (y))
#define DYNAMIC_STATE_NEXT(x)          SCM_SMOB_OBJECT_2(x)
#define DYNAMIC_STATE_NEXT_LOC(x)          SCM_SMOB_OBJECT_2_LOC(x)
#define SET_DYNAMIC_STATE_NEXT(x, y)   SCM_SET_SMOB_OBJECT_2((x), (y))

/* Weak lists of all dynamic states and all fluids.
 */
static SCM all_dynamic_states = SCM_EOL;
static SCM all_fluids = SCM_EOL;

/* Make sure that all states have the right size.  This must be called
   while fluid_admin_mutex is held.
*/
static void
resize_all_states ()
{
  SCM new_vectors, state;

  /* Replacing the vector of a dynamic state must be done atomically:
     the old values must be copied into the new vector and the new
     vector must be installed without someone modifying the old vector
     concurrently.  Since accessing a fluid should be lock-free, we
     need to put all threads to sleep when replacing a vector.
     However, when being single threaded, it is best not to do much.
     Therefore, we allocate the new vectors before going single
     threaded.
  */

  new_vectors = SCM_EOL;
  for (state = all_dynamic_states; !scm_is_null (state);
       state = DYNAMIC_STATE_NEXT (state))
    new_vectors = scm_cons (scm_c_make_vector (allocated_fluids_len,
					       SCM_BOOL_F),
			    new_vectors);

  scm_i_thread_put_to_sleep ();
  for (state = all_dynamic_states; !scm_is_null (state);
       state = DYNAMIC_STATE_NEXT (state))
    {
      SCM old_fluids = DYNAMIC_STATE_FLUIDS (state);
      SCM new_fluids = SCM_CAR (new_vectors);
      size_t i, old_len = SCM_SIMPLE_VECTOR_LENGTH (old_fluids);

      for (i = 0; i < old_len; i++)
	SCM_SIMPLE_VECTOR_SET (new_fluids, i,
			       SCM_SIMPLE_VECTOR_REF (old_fluids, i));
      SET_DYNAMIC_STATE_FLUIDS (state, new_fluids);
      new_vectors = SCM_CDR (new_vectors);
    }
  scm_i_thread_wake_up ();
}

/* This is called during GC, that is, while being single threaded.
   See next_fluid_num for a discussion why it is safe to access
   allocated_fluids here.
 */
static void *
scan_dynamic_states_and_fluids (void *dummy1 SCM_UNUSED,
				void *dummy2 SCM_UNUSED,
				void *dummy3 SCM_UNUSED)
{
  SCM *statep, *fluidp;

  /* Scan all fluids and deallocate the unmarked ones.
   */
  fluidp = &all_fluids;
  while (!scm_is_null (*fluidp))
    {
      if (!SCM_GC_MARK_P (*fluidp))
	{
	  allocated_fluids_num -= 1;
	  allocated_fluids[FLUID_NUM (*fluidp)] = 0;
	  *fluidp = FLUID_NEXT (*fluidp);
	}
      else
	fluidp = FLUID_NEXT_LOC (*fluidp);
    }

  /* Scan all dynamic states and remove the unmarked ones.  The live
     ones are updated for unallocated fluids.
  */
  statep = &all_dynamic_states;
  while (!scm_is_null (*statep))
    {
      if (!SCM_GC_MARK_P (*statep))
	*statep = DYNAMIC_STATE_NEXT (*statep);
      else
	{
	  SCM fluids = DYNAMIC_STATE_FLUIDS (*statep);
	  size_t len, i;

	  len = SCM_SIMPLE_VECTOR_LENGTH (fluids);
	  for (i = 0; i < len && i < allocated_fluids_len; i++)
	    if (allocated_fluids[i] == 0)
	      SCM_SIMPLE_VECTOR_SET (fluids, i, SCM_BOOL_F);

	  statep = DYNAMIC_STATE_NEXT_LOC (*statep);
	}
    }

  return NULL;
}

static size_t
fluid_free (SCM fluid)
{
  /* The real work is done in scan_dynamic_states_and_fluids.  We can
     not touch allocated_fluids etc here since a smob free routine can
     be run at any time, in any thread.
  */
  return 0;
}

static int
fluid_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
{
  scm_puts ("#<fluid ", port);
  scm_intprint ((int) FLUID_NUM (exp), 10, port);
  scm_putc ('>', port);
  return 1;
}

static size_t
next_fluid_num ()
{
  size_t n;

  scm_dynwind_begin (0);
  scm_i_dynwind_pthread_mutex_lock (&fluid_admin_mutex);

  if ((allocated_fluids_len > 0) &&
      (allocated_fluids_num == allocated_fluids_len))
    {
      /* All fluid numbers are in use.  Run a GC to try to free some
	 up.
      */
      scm_gc ();
    }

  if (allocated_fluids_num < allocated_fluids_len)
    {
      for (n = 0; n < allocated_fluids_len; n++)
	if (allocated_fluids[n] == 0)
	  break;
    }
  else
    {
      /* During the following call, the GC might run and elements of
	 allocated_fluids might bet set to zero.  Also,
	 allocated_fluids and allocated_fluids_len are used to scan
	 all dynamic states during GC.  Thus we need to make sure that
	 no GC can run while updating these two variables.
      */

      char *prev_allocated_fluids;
      char *new_allocated_fluids =
	scm_malloc (allocated_fluids_len + FLUID_GROW);

      /* Copy over old values and initialize rest.  GC can not run
	 during these two operations since there is no safe point in
	 them.
      */
      memcpy (new_allocated_fluids, allocated_fluids, allocated_fluids_len);
      memset (new_allocated_fluids + allocated_fluids_len, 0, FLUID_GROW);
      n = allocated_fluids_len;

      prev_allocated_fluids = allocated_fluids;
      allocated_fluids = new_allocated_fluids;
      allocated_fluids_len += FLUID_GROW;

      if (prev_allocated_fluids != NULL)
	free (prev_allocated_fluids);

      /* Now allocated_fluids and allocated_fluids_len are valid again
	 and we can allow GCs to occur.
      */
      resize_all_states ();
    }

  allocated_fluids_num += 1;
  allocated_fluids[n] = 1;

  scm_dynwind_end ();
  return n;
}

SCM_DEFINE (scm_make_fluid, "make-fluid", 0, 0, 0,
	    (),
	    "Return a newly created fluid.\n"
	    "Fluids are objects that can hold one\n"
	    "value per dynamic state.  That is, modifications to this value are\n"
	    "only visible to code that executes with the same dynamic state as\n"
	    "the modifying code.  When a new dynamic state is constructed, it\n"
	    "inherits the values from its parent.  Because each thread normally executes\n"
	    "with its own dynamic state, you can use fluids for thread local storage.")
#define FUNC_NAME s_scm_make_fluid
{
  SCM fluid;

  SCM_NEWSMOB2 (fluid, tc16_fluid,
		(scm_t_bits) next_fluid_num (), SCM_UNPACK (SCM_EOL));

  /* The GC must not run until the fluid is properly entered into the
     list.
  */
  scm_i_scm_pthread_mutex_lock (&fluid_admin_mutex);
  SET_FLUID_NEXT (fluid, all_fluids);
  all_fluids = fluid;
  scm_i_pthread_mutex_unlock (&fluid_admin_mutex);

  return fluid;
}
#undef FUNC_NAME

SCM_DEFINE (scm_fluid_p, "fluid?", 1, 0, 0,
	    (SCM obj),
	    "Return @code{#t} iff @var{obj} is a fluid; otherwise, return\n"
	    "@code{#f}.")
#define FUNC_NAME s_scm_fluid_p
{
  return scm_from_bool (IS_FLUID (obj));
}
#undef FUNC_NAME

int
scm_is_fluid (SCM obj)
{
  return IS_FLUID (obj);
}

size_t
scm_i_fluid_num (SCM fluid)
{
  return FLUID_NUM (fluid);
}

SCM_DEFINE (scm_fluid_ref, "fluid-ref", 1, 0, 0,
	    (SCM fluid),
	    "Return the value associated with @var{fluid} in the current\n"
	    "dynamic root.  If @var{fluid} has not been set, then return\n"
	    "@code{#f}.")
#define FUNC_NAME s_scm_fluid_ref
{
  SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state);

  SCM_VALIDATE_FLUID (1, fluid);
  return SCM_SIMPLE_VECTOR_REF (fluids, FLUID_NUM (fluid));
}
#undef FUNC_NAME

SCM
scm_i_fast_fluid_ref (size_t n)
{
  SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state);
  return SCM_SIMPLE_VECTOR_REF (fluids, n);
}

SCM_DEFINE (scm_fluid_set_x, "fluid-set!", 2, 0, 0,
	    (SCM fluid, SCM value),
	    "Set the value associated with @var{fluid} in the current dynamic root.")
#define FUNC_NAME s_scm_fluid_set_x
{
  SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state);

  SCM_VALIDATE_FLUID (1, fluid);
  SCM_SIMPLE_VECTOR_SET (fluids, FLUID_NUM (fluid), value);
  return SCM_UNSPECIFIED;
}
#undef FUNC_NAME

void
scm_i_fast_fluid_set_x (size_t n, SCM value)
{
  SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state);
  SCM_SIMPLE_VECTOR_SET (fluids, n, value);
}

static void
swap_fluids (SCM data)
{
  SCM fluids = SCM_CAR (data), vals = SCM_CDR (data);

  while (!SCM_NULL_OR_NIL_P (fluids))
    {
      SCM fl = SCM_CAR (fluids);
      SCM old_val = scm_fluid_ref (fl);
      scm_fluid_set_x (fl, SCM_CAR (vals));
      SCM_SETCAR (vals, old_val);
      fluids = SCM_CDR (fluids);
      vals = SCM_CDR (vals);
    }
}

/* Swap the fluid values in reverse order.  This is important when the
   same fluid appears multiple times in the fluids list.
*/

static void
swap_fluids_reverse_aux (SCM fluids, SCM vals)
{
  if (!SCM_NULL_OR_NIL_P (fluids))
    {
      SCM fl, old_val;

      swap_fluids_reverse_aux (SCM_CDR (fluids), SCM_CDR (vals));
      fl = SCM_CAR (fluids);
      old_val = scm_fluid_ref (fl);
      scm_fluid_set_x (fl, SCM_CAR (vals));
      SCM_SETCAR (vals, old_val);
    }
}

static void
swap_fluids_reverse (SCM data)
{
  swap_fluids_reverse_aux (SCM_CAR (data), SCM_CDR (data));
}

static SCM
apply_thunk (void *thunk)
{
  return scm_call_0 (SCM_PACK (thunk));
}

SCM_DEFINE (scm_with_fluids, "with-fluids*", 3, 0, 0,
	    (SCM fluids, SCM values, SCM thunk),
	    "Set @var{fluids} to @var{values} temporary, and call @var{thunk}.\n"
	    "@var{fluids} must be a list of fluids and @var{values} must be the same\n"
	    "number of their values to be applied.  Each substitution is done\n"
	    "one after another.  @var{thunk} must be a procedure with no argument.")
#define FUNC_NAME s_scm_with_fluids
{
  return scm_c_with_fluids (fluids, values,
			    apply_thunk, (void *) SCM_UNPACK (thunk));
}
#undef FUNC_NAME

SCM
scm_c_with_fluids (SCM fluids, SCM values, SCM (*cproc) (), void *cdata)
#define FUNC_NAME "scm_c_with_fluids"
{
  SCM ans, data;
  long flen, vlen;

  SCM_VALIDATE_LIST_COPYLEN (1, fluids, flen);
  SCM_VALIDATE_LIST_COPYLEN (2, values, vlen);
  if (flen != vlen)
    scm_out_of_range (s_scm_with_fluids, values);

  if (flen == 1)
    return scm_c_with_fluid (SCM_CAR (fluids), SCM_CAR (values),
			     cproc, cdata);

  data = scm_cons (fluids, values);
  scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
  scm_dynwind_rewind_handler_with_scm (swap_fluids, data,
				     SCM_F_WIND_EXPLICITLY);
  scm_dynwind_unwind_handler_with_scm (swap_fluids_reverse, data,
				     SCM_F_WIND_EXPLICITLY);
  ans = cproc (cdata);
  scm_dynwind_end ();
  return ans;
}
#undef FUNC_NAME

SCM_DEFINE (scm_with_fluid, "with-fluid*", 3, 0, 0,
	    (SCM fluid, SCM value, SCM thunk),
	    "Set @var{fluid} to @var{value} temporarily, and call @var{thunk}.\n"
	    "@var{thunk} must be a procedure with no argument.")
#define FUNC_NAME s_scm_with_fluid
{
  return scm_c_with_fluid (fluid, value,
			   apply_thunk, (void *) SCM_UNPACK (thunk));
}
#undef FUNC_NAME

SCM
scm_c_with_fluid (SCM fluid, SCM value, SCM (*cproc) (), void *cdata)
#define FUNC_NAME "scm_c_with_fluid"
{
  SCM ans;

  scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
  scm_dynwind_fluid (fluid, value);
  ans = cproc (cdata);
  scm_dynwind_end ();
  return ans;
}
#undef FUNC_NAME

static void
swap_fluid (SCM data)
{
  SCM f = SCM_CAR (data);
  SCM t = scm_fluid_ref (f);
  scm_fluid_set_x (f, SCM_CDR (data));
  SCM_SETCDR (data, t);
}

void
scm_dynwind_fluid (SCM fluid, SCM value)
{
  SCM data = scm_cons (fluid, value);
  scm_dynwind_rewind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY);
  scm_dynwind_unwind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY);
}

SCM
scm_i_make_initial_dynamic_state ()
{
  SCM fluids = scm_c_make_vector (allocated_fluids_len, SCM_BOOL_F);
  SCM state;
  SCM_NEWSMOB2 (state, tc16_dynamic_state,
		SCM_UNPACK (fluids), SCM_UNPACK (SCM_EOL));
  all_dynamic_states = state;
  return state;
}

SCM_DEFINE (scm_make_dynamic_state, "make-dynamic-state", 0, 1, 0,
	    (SCM parent),
	    "Return a copy of the dynamic state object @var{parent}\n"
	    "or of the current dynamic state when @var{parent} is omitted.")
#define FUNC_NAME s_scm_make_dynamic_state
{
  SCM fluids, state;

  if (SCM_UNBNDP (parent))
    parent = scm_current_dynamic_state ();

  scm_assert_smob_type (tc16_dynamic_state, parent);
  fluids = scm_vector_copy (DYNAMIC_STATE_FLUIDS (parent));
  SCM_NEWSMOB2 (state, tc16_dynamic_state,
		SCM_UNPACK (fluids), SCM_UNPACK (SCM_EOL));

  /* The GC must not run until the state is properly entered into the
     list.
  */
  scm_i_scm_pthread_mutex_lock (&fluid_admin_mutex);
  SET_DYNAMIC_STATE_NEXT (state, all_dynamic_states);
  all_dynamic_states = state;
  scm_i_pthread_mutex_unlock (&fluid_admin_mutex);

  return state;
}
#undef FUNC_NAME

SCM_DEFINE (scm_dynamic_state_p, "dynamic-state?", 1, 0, 0,
	    (SCM obj),
	    "Return @code{#t} if @var{obj} is a dynamic state object;\n"
	    "return @code{#f} otherwise")
#define FUNC_NAME s_scm_dynamic_state_p
{
  return scm_from_bool (IS_DYNAMIC_STATE (obj));
}
#undef FUNC_NAME

int
scm_is_dynamic_state (SCM obj)
{
  return IS_DYNAMIC_STATE (obj);
}

SCM_DEFINE (scm_current_dynamic_state, "current-dynamic-state", 0, 0, 0,
	    (),
	    "Return the current dynamic state object.")
#define FUNC_NAME s_scm_current_dynamic_state
{
  return SCM_I_CURRENT_THREAD->dynamic_state;
}
#undef FUNC_NAME

SCM_DEFINE (scm_set_current_dynamic_state, "set-current-dynamic-state", 1,0,0,
	    (SCM state),
	    "Set the current dynamic state object to @var{state}\n"
	    "and return the previous current dynamic state object.")
#define FUNC_NAME s_scm_set_current_dynamic_state
{
  scm_i_thread *t = SCM_I_CURRENT_THREAD;
  SCM old = t->dynamic_state;
  scm_assert_smob_type (tc16_dynamic_state, state);
  t->dynamic_state = state;
  return old;
}
#undef FUNC_NAME

static void
swap_dynamic_state (SCM loc)
{
  SCM_SETCAR (loc, scm_set_current_dynamic_state (SCM_CAR (loc)));
}

void
scm_dynwind_current_dynamic_state (SCM state)
{
  SCM loc = scm_cons (state, SCM_EOL);
  scm_assert_smob_type (tc16_dynamic_state, state);
  scm_dynwind_rewind_handler_with_scm (swap_dynamic_state, loc,
				     SCM_F_WIND_EXPLICITLY);
  scm_dynwind_unwind_handler_with_scm (swap_dynamic_state, loc,
				     SCM_F_WIND_EXPLICITLY);
}

void *
scm_c_with_dynamic_state (SCM state, void *(*func)(void *), void *data)
{
  void *result;
  scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
  scm_dynwind_current_dynamic_state (state);
  result = func (data);
  scm_dynwind_end ();
  return result;
}

SCM_DEFINE (scm_with_dynamic_state, "with-dynamic-state", 2, 0, 0,
	    (SCM state, SCM proc),
	    "Call @var{proc} while @var{state} is the current dynamic\n"
	    "state object.")
#define FUNC_NAME s_scm_with_dynamic_state
{
  SCM result;
  scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
  scm_dynwind_current_dynamic_state (state);
  result = scm_call_0 (proc);
  scm_dynwind_end ();
  return result;
}
#undef FUNC_NAME

void
scm_fluids_prehistory ()
{
  tc16_fluid = scm_make_smob_type ("fluid", 0);
  scm_set_smob_free (tc16_fluid, fluid_free);
  scm_set_smob_print (tc16_fluid, fluid_print);

  tc16_dynamic_state = scm_make_smob_type ("dynamic-state", 0);
  scm_set_smob_mark (tc16_dynamic_state, scm_markcdr);

  scm_c_hook_add (&scm_after_sweep_c_hook, scan_dynamic_states_and_fluids,
		  0, 0);
}

void
scm_init_fluids ()
{
#include "libguile/fluids.x"
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/


code:
/* classes: h_files */

#ifndef SCM_FLUIDS_H
#define SCM_FLUIDS_H

/* Copyright (C) 1996,2000,2001, 2006 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libguile/__scm.h"
#include "libguile/root.h"
#include "libguile/vectors.h"

/* Fluids.

   Fluids are objects of a certain type (a smob) that can hold one SCM
   value per dynamic state.  That is, modifications to this value are
   only visible to code that executes with the same dynamic state as
   the modifying code.  When a new dynamic state is constructed, it
   inherits the values from its parent.  Because each thread executes
   with its own dynamic state, you can use fluids for thread local
   storage.

   Each fluid is identified by a small integer.  This integer is used
   to index a vector that holds the values of all fluids.  A dynamic
   state consists of this vector, wrapped in a smob so that the vector
   can grow.
 */

/* The fastest way to acces/modify the value of a fluid.  These macros
   do no error checking at all.  The first argument is the index
   number of the fluid, obtained via SCM_FLUID_NUM, not the fluid
   itself.  You must make sure that the fluid remains protected as
   long you use its number since numbers of unused fluids are reused
   eventually.
*/

#define SCM_FLUID_NUM(x)             scm_i_fluid_num (x)
#define SCM_FAST_FLUID_REF(n)        scm_i_fast_fluid_ref (n)
#define SCM_FAST_FLUID_SET_X(n, val) scm_i_fast_fluid_set_x ((n),(val))

SCM_API SCM scm_make_fluid (void);
SCM_API int scm_is_fluid (SCM obj);
SCM_API SCM scm_fluid_p (SCM fl);
SCM_API SCM scm_fluid_ref (SCM fluid);
SCM_API SCM scm_fluid_set_x (SCM fluid, SCM value);
SCM_API size_t scm_i_fluid_num (SCM fl);
SCM_API SCM scm_i_fast_fluid_ref (size_t n);
SCM_API void scm_i_fast_fluid_set_x (size_t n, SCM val);

SCM_API SCM scm_c_with_fluids (SCM fluids, SCM vals,
			       SCM (*cproc)(void *), void *cdata);
SCM_API SCM scm_c_with_fluid (SCM fluid, SCM val,
			      SCM (*cproc)(void *), void *cdata);
SCM_API SCM scm_with_fluids (SCM fluids, SCM vals, SCM thunk);
SCM_API SCM scm_with_fluid (SCM fluid, SCM val, SCM thunk);

SCM_API void scm_dynwind_fluid (SCM fluid, SCM value);

SCM_API SCM scm_make_dynamic_state (SCM parent);
SCM_API SCM scm_dynamic_state_p (SCM obj);
SCM_API int scm_is_dynamic_state (SCM obj);
SCM_API SCM scm_current_dynamic_state (void);
SCM_API SCM scm_set_current_dynamic_state (SCM state);
SCM_API void scm_dynwind_current_dynamic_state (SCM state);
SCM_API void *scm_c_with_dynamic_state (SCM state,
					void *(*func)(void *), void *data);
SCM_API SCM scm_with_dynamic_state (SCM state, SCM proc);

SCM_API SCM scm_i_make_initial_dynamic_state (void);

SCM_API void scm_fluids_prehistory (void);
SCM_API void scm_init_fluids (void);

#endif  /* SCM_FLUIDS_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/