[bpt/guile.git] / libguile / load.c

/*	Copyright (C) 1995,1996 Free Software Foundation, Inc.
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this software; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * As a special exception, the Free Software Foundation gives permission
 * for additional uses of the text contained in its release of GUILE.
 *
 * The exception is that, if you link the GUILE library with other files
 * to produce an executable, this does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * Your use of that executable is in no way restricted on account of
 * linking the GUILE library code into it.
 *
 * This exception does not however invalidate any other reasons why
 * the executable file might be covered by the GNU General Public License.
 *
 * This exception applies only to the code released by the
 * Free Software Foundation under the name GUILE.  If you copy
 * code from other Free Software Foundation releases into a copy of
 * GUILE, as the General Public License permits, the exception does
 * not apply to the code that you add in this way.  To avoid misleading
 * anyone as to the status of such modified files, you must delete
 * this exception notice from them.
 *
 * If you write modifications of your own for GUILE, it is your choice
 * whether to permit this exception to apply to your modifications.
 * If you do not wish that, delete this exception notice.  
 */
\f

#include <stdio.h>
#include "_scm.h"
#include "libpath.h"
#include "fports.h"
#include "read.h"
#include "eval.h"

#include "load.h"

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

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

#ifndef R_OK
#define R_OK 4
#endif

\f
/* Loading a file, given an absolute filename.  */

/* Hook to run when we load a file, perhaps to announce the fact somewhere.
   Applied to the full name of the file.  */
static SCM *scm_loc_load_hook;

SCM_PROC(s_primitive_load, "primitive-load", 1, 2, 0, scm_primitive_load);
SCM 
scm_primitive_load (filename, case_insensitive_p, sharp)
     SCM filename;
     SCM case_insensitive_p;
     SCM sharp;
{
  SCM hook = *scm_loc_load_hook;
  SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
	      SCM_ARG1, s_primitive_load);
  SCM_ASSERT (hook == SCM_BOOL_F
	      || (scm_procedure_p (hook) == SCM_BOOL_T),
	      hook, "value of %load-hook is neither a procedure nor #f",
	      s_primitive_load);

  if (hook != SCM_BOOL_F)
    scm_apply (hook, scm_listify (filename, SCM_UNDEFINED), SCM_EOL);

  {
    SCM form, port;
    port = scm_open_file (filename,
			  scm_makfromstr ("r", (scm_sizet) sizeof (char), 0));
    while (1)
      {
	form = scm_read (port, case_insensitive_p, sharp);
	if (SCM_EOF_VAL == form)
	  break;
	scm_eval_x (form);
      }
    scm_close_port (port);
  }
  return SCM_UNSPECIFIED;
}

\f
/* Builtin path to scheme library files. */
#ifdef SCM_PKGDATA_DIR
SCM_PROC (s_sys_package_data_dir, "%package-data-dir", 0, 0, 0, scm_sys_package_data_dir);
SCM
scm_sys_package_data_dir ()
{
  return scm_makfrom0str (SCM_PKGDATA_DIR);
}
#endif /* SCM_PKGDATA_DIR */

\f
/* Initializing the load path, and searching it.  */

/* List of names of directories we search for files to load.  */
static SCM *scm_loc_load_path;

/* List of extensions we try adding to the filenames.  */
static SCM *scm_loc_load_extensions;

/* Initialize the global variable %load-path, given the value of the
   SCM_SITE_DIR and SCM_LIBRARY_DIR preprocessor symbols and the
   SCHEME_LOAD_PATH environment variable.  */
void
scm_init_load_path ()
{
  SCM path = SCM_EOL;

#ifdef SCM_LIBRARY_DIR
  path = scm_cons2 (scm_makfrom0str (SCM_SITE_DIR),
		    scm_makfrom0str (SCM_LIBRARY_DIR),
		    path);
#endif /* SCM_LIBRARY_DIR */
  
  {
    char *path_string = getenv ("SCHEME_LOAD_PATH");

    if (path_string && path_string[0] != '\0')
      {
	char *scan, *elt_end;

	/* Scan backwards from the end of the string, to help
           construct the list in the right order.  */
	scan = elt_end = path_string + strlen (path_string);
	do {
	  /* Scan back to the beginning of the current element.  */
	  do scan--;
	  while (scan >= path_string && *scan != ':');
	  path = scm_cons (scm_makfromstr (scan + 1, elt_end - (scan + 1), 0),
			   path);
	  elt_end = scan;
	} while (scan >= path_string);
      }
  }

  *scm_loc_load_path = path;
}


/* Search %load-path for a directory containing a file named FILENAME.
   The file must be readable, and not a directory.
   If we find one, return its full filename; otherwise, return #f.
   If FILENAME is absolute, return it unchanged.  */
SCM_PROC(s_sys_search_load_path, "%search-load-path", 1, 0, 0, scm_sys_search_load_path);
SCM 
scm_sys_search_load_path (filename)
     SCM filename;
{
  SCM path = *scm_loc_load_path;
  SCM exts = *scm_loc_load_extensions;
  char *buf;
  int filename_len;
  int max_path_len;
  int max_ext_len;

  SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
	      SCM_ARG1, s_sys_search_load_path);
  SCM_ASSERT (scm_ilength (path) >= 0, path, "load path is not a proper list",
	      s_sys_search_load_path);
  SCM_ASSERT (scm_ilength (exts) >= 0, exts,
	      "load extension list is not a proper list",
	      s_sys_search_load_path);
  filename_len = SCM_ROLENGTH (filename);

  /* If FILENAME is absolute, return it unchanged.  */
  if (filename_len >= 1
      && SCM_ROCHARS (filename)[0] == '/')
    return filename;

  /* Find the length of the longest element of path.  */
  {
    SCM walk;

    max_path_len = 0;
    for (walk = path; SCM_NIMP (walk); walk = SCM_CDR (walk))
      {
	SCM elt = SCM_CAR (walk);
	SCM_ASSERT (SCM_NIMP (elt) && SCM_ROSTRINGP (elt), elt,
		    "load path is not a list of strings",
		    s_sys_search_load_path);
	if (SCM_LENGTH (elt) > max_path_len)
	  max_path_len = SCM_LENGTH (elt);
      }
  }

  /* Find the length of the longest element of the load extensions
     list.  */
  {
    SCM walk;

    max_ext_len = 0;
    for (walk = exts; SCM_NIMP (walk); walk = SCM_CDR (walk))
      {
	SCM elt = SCM_CAR (walk);
	SCM_ASSERT (SCM_NIMP (elt) && SCM_ROSTRINGP (elt), elt,
		    "load extension list is not a list of strings",
		    s_sys_search_load_path);
	if (SCM_LENGTH (elt) > max_ext_len)
	  max_ext_len = SCM_LENGTH (elt);
      }
  }

  SCM_DEFER_INTS;

  buf = scm_must_malloc (max_path_len + 1 + filename_len + max_ext_len + 1,
			 s_sys_search_load_path);

  /* Try every path element.  At this point, we know it's a proper
     list of strings.  */
  for (; SCM_NIMP (path); path = SCM_CDR (path))
    {
      SCM path_elt = SCM_CAR (path);

      /* Try every extension.  At this point, we know it's a proper
         list of strings.  */
      for (exts = *scm_loc_load_extensions;
	   SCM_NIMP (exts);
	   exts = SCM_CDR (exts))
	{
	  SCM ext_elt = SCM_CAR (exts);
	  int i;

	  /* Concatenate the path name, the filename, and the extension. */
	  i = SCM_ROLENGTH (path_elt);
	  memcpy (buf, SCM_ROCHARS (path_elt), i);
	  buf[i++] = '/';
	  memcpy (buf + i, SCM_ROCHARS (filename), filename_len);
	  i += filename_len;
	  memcpy (buf + i, SCM_ROCHARS (ext_elt), SCM_LENGTH (ext_elt));
	  i += SCM_LENGTH (ext_elt);
	  buf[i] = '\0';

	  {
	    struct stat mode;

	    if (stat (buf, &mode) >= 0
		&& ! (mode.st_mode & S_IFDIR)
		&& access (buf, R_OK) == 0)
	      {
		SCM result = scm_makfromstr (buf, i, 0);
		scm_must_free (buf);
		SCM_ALLOW_INTS;
		return result;
	      }
	  }
	}
    }
  
  scm_must_free (buf);
  SCM_ALLOW_INTS;
  return SCM_BOOL_F;
}


SCM_PROC(s_primitive_load_path, "primitive-load-path", 1, 2, 0, scm_primitive_load_path);
SCM 
scm_primitive_load_path (filename, case_insensitive_p, sharp)
     SCM filename;
     SCM case_insensitive_p;
     SCM sharp;
{
  SCM full_filename;

  SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
	      SCM_ARG1, s_primitive_load_path);

  full_filename = scm_sys_search_load_path (filename);

  if (SCM_FALSEP (full_filename))
    {
      int absolute = (SCM_LENGTH (filename) >= 1
		      && SCM_ROCHARS (filename)[0] == '/');
      scm_misc_error (s_primitive_load_path,
		      (absolute
		       ? "Unable to load file %S"
		       : "Unable to find file %S in load path"),
		      scm_listify (filename, SCM_UNDEFINED));
    }

  return scm_primitive_load (full_filename, case_insensitive_p, sharp);
}

\f

void
scm_init_load ()
{
  scm_loc_load_path = SCM_CDRLOC(scm_sysintern("%load-path", SCM_EOL));
  scm_loc_load_extensions
    = SCM_CDRLOC(scm_sysintern("%load-extensions",
			       scm_listify (scm_makfrom0str (""),
					    scm_makfrom0str (".scm"),
					    SCM_UNDEFINED)));
  scm_loc_load_hook = SCM_CDRLOC(scm_sysintern("%load-hook", SCM_BOOL_F));

#include "load.x"
}
Commit	Line	Data
0f2d19dd JB	1	/* Copyright (C) 1995,1996 Free Software Foundation, Inc.
	2	*
	3	* This program is free software; you can redistribute it and/or modify
	4	* it under the terms of the GNU General Public License as published by
	5	* the Free Software Foundation; either version 2, or (at your option)
	6	* any later version.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License
	14	* along with this software; see the file COPYING. If not, write to
	15	* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	16	*
	17	* As a special exception, the Free Software Foundation gives permission
	18	* for additional uses of the text contained in its release of GUILE.
	19	*
	20	* The exception is that, if you link the GUILE library with other files
	21	* to produce an executable, this does not by itself cause the
	22	* resulting executable to be covered by the GNU General Public License.
	23	* Your use of that executable is in no way restricted on account of
	24	* linking the GUILE library code into it.
	25	*
	26	* This exception does not however invalidate any other reasons why
	27	* the executable file might be covered by the GNU General Public License.
	28	*
	29	* This exception applies only to the code released by the
	30	* Free Software Foundation under the name GUILE. If you copy
	31	* code from other Free Software Foundation releases into a copy of
	32	* GUILE, as the General Public License permits, the exception does
	33	* not apply to the code that you add in this way. To avoid misleading
	34	* anyone as to the status of such modified files, you must delete
	35	* this exception notice from them.
	36	*
	37	* If you write modifications of your own for GUILE, it is your choice
	38	* whether to permit this exception to apply to your modifications.
	39	* If you do not wish that, delete this exception notice.
	40	*/
	41	\f
	42
	43	#include <stdio.h>
	44	#include "_scm.h"
06721500	45	#include "libpath.h"
20e6290e JB	46	#include "fports.h"
	47	#include "read.h"
	48	#include "eval.h"
	49
	50	#include "load.h"
06721500 JB	51
	52	#include <sys/types.h>
	53	#include <sys/stat.h>
	54
	55	#ifdef HAVE_UNISTD_H
	56	#include <unistd.h>
	57	#endif /* HAVE_UNISTD_H */
	58
	59	#ifndef R_OK
	60	#define R_OK 4
	61	#endif
0f2d19dd JB	62
0f2d19dd JB	63	\f
06721500	64	/* Loading a file, given an absolute filename. */
0f2d19dd	65
26544b96 JB	66	/* Hook to run when we load a file, perhaps to announce the fact somewhere.
	67	Applied to the full name of the file. */
	68	static SCM *scm_loc_load_hook;
	69
523f5266	70	SCM_PROC(s_primitive_load, "primitive-load", 1, 2, 0, scm_primitive_load);
0f2d19dd	71	SCM
b9d5d654	72	scm_primitive_load (filename, case_insensitive_p, sharp)
0f2d19dd	73	SCM filename;
06721500	74	SCM case_insensitive_p;
0f2d19dd	75	SCM sharp;
0f2d19dd	76	{
26544b96	77	SCM hook = *scm_loc_load_hook;
06721500	78	SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
523f5266	79	SCM_ARG1, s_primitive_load);
26544b96 JB	80	SCM_ASSERT (hook == SCM_BOOL_F
	81	\|\| (scm_procedure_p (hook) == SCM_BOOL_T),
	82	hook, "value of %load-hook is neither a procedure nor #f",
	83	s_primitive_load);
	84
	85	if (hook != SCM_BOOL_F)
	86	scm_apply (hook, scm_listify (filename, SCM_UNDEFINED), SCM_EOL);
	87
0f2d19dd JB	88	{
	89	SCM form, port;
	90	port = scm_open_file (filename,
	91	scm_makfromstr ("r", (scm_sizet) sizeof (char), 0));
0f2d19dd JB	92	while (1)
0f2d19dd JB	93	{
06721500	94	form = scm_read (port, case_insensitive_p, sharp);
0f2d19dd JB	95	if (SCM_EOF_VAL == form)
	96	break;
	97	scm_eval_x (form);
	98	}
	99	scm_close_port (port);
	100	}
b59b97ba	101	return SCM_UNSPECIFIED;
0f2d19dd JB	102	}
	103
	104	\f
3feedb00 MD	105	/* Builtin path to scheme library files. */
	106	#ifdef SCM_PKGDATA_DIR
	107	SCM_PROC (s_sys_package_data_dir, "%package-data-dir", 0, 0, 0, scm_sys_package_data_dir);
	108	SCM
	109	scm_sys_package_data_dir ()
	110	{
	111	return scm_makfrom0str (SCM_PKGDATA_DIR);
	112	}
	113	#endif /* SCM_PKGDATA_DIR */
	114
	115	\f
06721500	116	/* Initializing the load path, and searching it. */
0f2d19dd	117
26544b96	118	/* List of names of directories we search for files to load. */
06721500 JB	119	static SCM *scm_loc_load_path;
06721500 JB	120
26544b96 JB	121	/* List of extensions we try adding to the filenames. */
	122	static SCM *scm_loc_load_extensions;
	123
06721500	124	/* Initialize the global variable %load-path, given the value of the
3feedb00 MD	125	SCM_SITE_DIR and SCM_LIBRARY_DIR preprocessor symbols and the
3feedb00 MD	126	SCHEME_LOAD_PATH environment variable. */
0f2d19dd	127	void
06721500 JB	128	scm_init_load_path ()
	129	{
	130	SCM path = SCM_EOL;
	131
3feedb00 MD	132	#ifdef SCM_LIBRARY_DIR
	133	path = scm_cons2 (scm_makfrom0str (SCM_SITE_DIR),
	134	scm_makfrom0str (SCM_LIBRARY_DIR),
	135	path);
	136	#endif /* SCM_LIBRARY_DIR */
06721500 JB	137
	138	{
	139	char *path_string = getenv ("SCHEME_LOAD_PATH");
	140
	141	if (path_string && path_string[0] != '\0')
	142	{
	143	char scan, elt_end;
	144
	145	/* Scan backwards from the end of the string, to help
	146	construct the list in the right order. */
	147	scan = elt_end = path_string + strlen (path_string);
	148	do {
	149	/* Scan back to the beginning of the current element. */
	150	do scan--;
	151	while (scan >= path_string && *scan != ':');
	152	path = scm_cons (scm_makfromstr (scan + 1, elt_end - (scan + 1), 0),
	153	path);
	154	elt_end = scan;
	155	} while (scan >= path_string);
	156	}
	157	}
	158
	159	*scm_loc_load_path = path;
	160	}
	161
	162
	163	/* Search %load-path for a directory containing a file named FILENAME.
	164	The file must be readable, and not a directory.
26544b96 JB	165	If we find one, return its full filename; otherwise, return #f.
26544b96 JB	166	If FILENAME is absolute, return it unchanged. */
06721500 JB	167	SCM_PROC(s_sys_search_load_path, "%search-load-path", 1, 0, 0, scm_sys_search_load_path);
	168	SCM
	169	scm_sys_search_load_path (filename)
	170	SCM filename;
	171	{
	172	SCM path = *scm_loc_load_path;
26544b96	173	SCM exts = *scm_loc_load_extensions;
06721500	174	char *buf;
06721500	175	int filename_len;
26544b96 JB	176	int max_path_len;
26544b96 JB	177	int max_ext_len;
06721500 JB	178
	179	SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
	180	SCM_ARG1, s_sys_search_load_path);
26544b96 JB	181	SCM_ASSERT (scm_ilength (path) >= 0, path, "load path is not a proper list",
	182	s_sys_search_load_path);
	183	SCM_ASSERT (scm_ilength (exts) >= 0, exts,
	184	"load extension list is not a proper list",
	185	s_sys_search_load_path);
06721500 JB	186	filename_len = SCM_ROLENGTH (filename);
06721500 JB	187
26544b96 JB	188	/* If FILENAME is absolute, return it unchanged. */
	189	if (filename_len >= 1
	190	&& SCM_ROCHARS (filename)[0] == '/')
	191	return filename;
	192
	193	/* Find the length of the longest element of path. */
	194	{
	195	SCM walk;
	196
	197	max_path_len = 0;
	198	for (walk = path; SCM_NIMP (walk); walk = SCM_CDR (walk))
	199	{
	200	SCM elt = SCM_CAR (walk);
	201	SCM_ASSERT (SCM_NIMP (elt) && SCM_ROSTRINGP (elt), elt,
	202	"load path is not a list of strings",
	203	s_sys_search_load_path);
	204	if (SCM_LENGTH (elt) > max_path_len)
	205	max_path_len = SCM_LENGTH (elt);
	206	}
	207	}
	208
	209	/* Find the length of the longest element of the load extensions
	210	list. */
	211	{
	212	SCM walk;
	213
	214	max_ext_len = 0;
	215	for (walk = exts; SCM_NIMP (walk); walk = SCM_CDR (walk))
	216	{
	217	SCM elt = SCM_CAR (walk);
	218	SCM_ASSERT (SCM_NIMP (elt) && SCM_ROSTRINGP (elt), elt,
	219	"load extension list is not a list of strings",
	220	s_sys_search_load_path);
	221	if (SCM_LENGTH (elt) > max_ext_len)
	222	max_ext_len = SCM_LENGTH (elt);
	223	}
	224	}
	225
06721500 JB	226	SCM_DEFER_INTS;
06721500 JB	227
26544b96 JB	228	buf = scm_must_malloc (max_path_len + 1 + filename_len + max_ext_len + 1,
26544b96 JB	229	s_sys_search_load_path);
06721500	230
26544b96 JB	231	/* Try every path element. At this point, we know it's a proper
	232	list of strings. */
	233	for (; SCM_NIMP (path); path = SCM_CDR (path))
06721500	234	{
26544b96 JB	235	SCM path_elt = SCM_CAR (path);
	236
	237	/* Try every extension. At this point, we know it's a proper
	238	list of strings. */
	239	for (exts = *scm_loc_load_extensions;
	240	SCM_NIMP (exts);
	241	exts = SCM_CDR (exts))
06721500	242	{
26544b96 JB	243	SCM ext_elt = SCM_CAR (exts);
	244	int i;
	245
	246	/* Concatenate the path name, the filename, and the extension. */
	247	i = SCM_ROLENGTH (path_elt);
	248	memcpy (buf, SCM_ROCHARS (path_elt), i);
	249	buf[i++] = '/';
	250	memcpy (buf + i, SCM_ROCHARS (filename), filename_len);
	251	i += filename_len;
	252	memcpy (buf + i, SCM_ROCHARS (ext_elt), SCM_LENGTH (ext_elt));
	253	i += SCM_LENGTH (ext_elt);
	254	buf[i] = '\0';
06721500 JB	255
	256	{
	257	struct stat mode;
	258
	259	if (stat (buf, &mode) >= 0
	260	&& ! (mode.st_mode & S_IFDIR)
	261	&& access (buf, R_OK) == 0)
	262	{
26544b96	263	SCM result = scm_makfromstr (buf, i, 0);
06721500 JB	264	scm_must_free (buf);
	265	SCM_ALLOW_INTS;
	266	return result;
	267	}
	268	}
	269	}
06721500 JB	270	}
	271
	272	scm_must_free (buf);
	273	SCM_ALLOW_INTS;
	274	return SCM_BOOL_F;
	275	}
	276
	277
26544b96	278	SCM_PROC(s_primitive_load_path, "primitive-load-path", 1, 2, 0, scm_primitive_load_path);
06721500	279	SCM
b9d5d654	280	scm_primitive_load_path (filename, case_insensitive_p, sharp)
06721500 JB	281	SCM filename;
	282	SCM case_insensitive_p;
	283	SCM sharp;
	284	{
26544b96 JB	285	SCM full_filename;
	286
	287	SCM_ASSERT (SCM_NIMP (filename) && SCM_ROSTRINGP (filename), filename,
	288	SCM_ARG1, s_primitive_load_path);
	289
	290	full_filename = scm_sys_search_load_path (filename);
	291
dbece3a2 GH	292	if (SCM_FALSEP (full_filename))
dbece3a2 GH	293	{
26544b96 JB	294	int absolute = (SCM_LENGTH (filename) >= 1
26544b96 JB	295	&& SCM_ROCHARS (filename)[0] == '/');
523f5266	296	scm_misc_error (s_primitive_load_path,
26544b96 JB	297	(absolute
	298	? "Unable to load file %S"
	299	: "Unable to find file %S in load path"),
	300	scm_listify (filename, SCM_UNDEFINED));
dbece3a2	301	}
26544b96	302
b9d5d654	303	return scm_primitive_load (full_filename, case_insensitive_p, sharp);
06721500 JB	304	}
	305
	306	\f
	307
0f2d19dd JB	308	void
0f2d19dd JB	309	scm_init_load ()
0f2d19dd	310	{
25d8012c	311	scm_loc_load_path = SCM_CDRLOC(scm_sysintern("%load-path", SCM_EOL));
26544b96 JB	312	scm_loc_load_extensions
	313	= SCM_CDRLOC(scm_sysintern("%load-extensions",
	314	scm_listify (scm_makfrom0str (""),
	315	scm_makfrom0str (".scm"),
	316	SCM_UNDEFINED)));
	317	scm_loc_load_hook = SCM_CDRLOC(scm_sysintern("%load-hook", SCM_BOOL_F));
06721500	318
0f2d19dd JB	319	#include "load.x"
0f2d19dd JB	320	}