1 /* Copyright (C) 1995,1996,1998,1999, 2000 Free Software Foundation, Inc.
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)
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.
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, Inc., 59 Temple Place, Suite 330,
16 * Boston, MA 02111-1307 USA
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
21 * The exception is that, if you link the GUILE library with other files
22 * to produce an executable, this does not by itself cause the
23 * resulting executable to be covered by the GNU General Public License.
24 * Your use of that executable is in no way restricted on account of
25 * linking the GUILE library code into it.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
30 * This exception applies only to the code released by the
31 * Free Software Foundation under the name GUILE. If you copy
32 * code from other Free Software Foundation releases into a copy of
33 * GUILE, as the General Public License permits, the exception does
34 * not apply to the code that you add in this way. To avoid misleading
35 * anyone as to the status of such modified files, you must delete
36 * this exception notice from them.
38 * If you write modifications of your own for GUILE, it is your choice
39 * whether to permit this exception to apply to your modifications.
40 * If you do not wish that, delete this exception notice. */
42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
43 gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
47 #include "libguile/_scm.h"
54 #include "libguile/unif.h"
55 #include "libguile/eval.h"
56 #include "libguile/ports.h"
57 #include "libguile/read.h"
58 #include "libguile/root.h"
59 #include "libguile/strings.h"
60 #include "libguile/modules.h"
61 #include "libguile/validate.h"
63 #include "libguile/strports.h"
71 /* {Ports - string ports}
76 write_buf/write_end point to the ends of the allocated string.
77 read_buf/read_end in principle point to the part of the string which
78 has been written to, but this is only updated after a flush.
79 read_pos and write_pos in principle should be equal, but this is only true
80 when rw_active is SCM_PORT_NEITHER.
84 static scm_bits_t scm_tc16_strport
;
88 stfill_buffer (SCM port
)
90 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
92 if (pt
->read_pos
>= pt
->read_end
)
95 return scm_return_first_int (*pt
->read_pos
, port
);
98 /* change the size of a port's string to new_size. this doesn't
99 change read_buf_size. */
101 st_resize_port (scm_port
*pt
, off_t new_size
)
103 SCM old_stream
= SCM_PACK (pt
->stream
);
104 SCM new_stream
= scm_makstr (new_size
, 0);
105 unsigned long int old_size
= SCM_STRING_LENGTH (old_stream
);
106 unsigned long int min_size
= min (old_size
, new_size
);
109 off_t index
= pt
->write_pos
- pt
->write_buf
;
111 pt
->write_buf_size
= new_size
;
113 for (i
= 0; i
!= min_size
; ++i
)
114 SCM_STRING_CHARS (new_stream
) [i
] = SCM_STRING_CHARS (old_stream
) [i
];
118 pt
->stream
= new_stream
;
119 pt
->read_buf
= pt
->write_buf
= SCM_STRING_UCHARS (new_stream
);
120 pt
->read_pos
= pt
->write_pos
= pt
->write_buf
+ index
;
121 pt
->write_end
= pt
->write_buf
+ pt
->write_buf_size
;
122 pt
->read_end
= pt
->read_buf
+ pt
->read_buf_size
;
126 /* amount by which write_buf is expanded. */
127 #define SCM_WRITE_BLOCK 80
129 /* ensure that write_pos < write_end by enlarging the buffer when
130 necessary. update read_buf to account for written chars. */
134 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
136 if (pt
->write_pos
== pt
->write_end
)
138 st_resize_port (pt
, pt
->write_buf_size
+ SCM_WRITE_BLOCK
);
140 pt
->read_pos
= pt
->write_pos
;
141 if (pt
->read_pos
> pt
->read_end
)
143 pt
->read_end
= (unsigned char *) pt
->read_pos
;
144 pt
->read_buf_size
= pt
->read_end
- pt
->read_buf
;
146 pt
->rw_active
= SCM_PORT_NEITHER
;
150 st_write (SCM port
, const void *data
, size_t size
)
152 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
153 const char *input
= (char *) data
;
157 int space
= pt
->write_end
- pt
->write_pos
;
158 int write_len
= (size
> space
) ? space
: size
;
160 strncpy ((char *) pt
->write_pos
, input
, write_len
);
161 pt
->write_pos
+= write_len
;
164 if (write_len
== space
)
170 st_end_input (SCM port
, int offset
)
172 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
174 if (pt
->read_pos
- pt
->read_buf
< offset
)
175 scm_misc_error ("st_end_input", "negative position", SCM_EOL
);
177 pt
->write_pos
= (unsigned char *) (pt
->read_pos
= pt
->read_pos
- offset
);
178 pt
->rw_active
= SCM_PORT_NEITHER
;
182 st_seek (SCM port
, off_t offset
, int whence
)
184 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
187 if (pt
->rw_active
== SCM_PORT_READ
&& offset
== 0 && whence
== SEEK_CUR
)
188 /* special case to avoid disturbing the unread-char buffer. */
190 if (pt
->read_buf
== pt
->putback_buf
)
192 target
= pt
->saved_read_pos
- pt
->saved_read_buf
193 - (pt
->read_end
- pt
->read_pos
);
197 target
= pt
->read_pos
- pt
->read_buf
;
201 /* all other cases. */
203 if (pt
->rw_active
== SCM_PORT_WRITE
)
206 if (pt
->rw_active
== SCM_PORT_READ
)
207 scm_end_input (port
);
212 target
= pt
->read_pos
- pt
->read_buf
+ offset
;
215 target
= pt
->read_end
- pt
->read_buf
+ offset
;
217 default: /* SEEK_SET */
223 scm_misc_error ("st_seek", "negative offset", SCM_EOL
);
225 if (target
>= pt
->write_buf_size
)
227 if (!(SCM_CELL_WORD_0 (port
) & SCM_WRTNG
))
229 if (target
> pt
->write_buf_size
)
231 scm_misc_error ("st_seek",
232 "seek past end of read-only strport",
238 st_resize_port (pt
, target
+ (target
== pt
->write_buf_size
243 pt
->read_pos
= pt
->write_pos
= pt
->read_buf
+ target
;
244 if (pt
->read_pos
> pt
->read_end
)
246 pt
->read_end
= (unsigned char *) pt
->read_pos
;
247 pt
->read_buf_size
= pt
->read_end
- pt
->read_buf
;
254 st_truncate (SCM port
, off_t length
)
256 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
258 if (length
> pt
->write_buf_size
)
259 st_resize_port (pt
, length
);
261 pt
->read_buf_size
= length
;
262 pt
->read_end
= pt
->read_buf
+ length
;
263 if (pt
->read_pos
> pt
->read_end
)
264 pt
->read_pos
= pt
->read_end
;
266 if (pt
->write_pos
> pt
->read_end
)
267 pt
->write_pos
= pt
->read_end
;
271 scm_mkstrport (SCM pos
, SCM str
, long modes
, const char *caller
)
277 SCM_ASSERT (SCM_INUMP(pos
) && SCM_INUM(pos
) >= 0, pos
, SCM_ARG1
, caller
);
278 SCM_ASSERT (SCM_STRINGP (str
), str
, SCM_ARG1
, caller
);
279 str_len
= SCM_STRING_LENGTH (str
);
280 if (SCM_INUM (pos
) > str_len
)
281 scm_out_of_range (caller
, pos
);
282 if (!((modes
& SCM_WRTNG
) || (modes
& SCM_RDNG
)))
283 scm_misc_error ("scm_mkstrport", "port must read or write", SCM_EOL
);
286 pt
= scm_add_to_port_table (z
);
287 SCM_SET_CELL_TYPE (z
, scm_tc16_strport
| modes
);
288 SCM_SETPTAB_ENTRY (z
, pt
);
289 SCM_SETSTREAM (z
, SCM_UNPACK (str
));
290 pt
->write_buf
= pt
->read_buf
= SCM_STRING_UCHARS (str
);
291 pt
->read_pos
= pt
->write_pos
= pt
->read_buf
+ SCM_INUM (pos
);
292 pt
->write_buf_size
= pt
->read_buf_size
= str_len
;
293 pt
->write_end
= pt
->read_end
= pt
->read_buf
+ pt
->read_buf_size
;
299 /* ensure write_pos is writable. */
300 if ((modes
& SCM_WRTNG
) && pt
->write_pos
== pt
->write_end
)
305 /* create a new string from a string port's buffer. */
306 SCM
scm_strport_to_string (SCM port
)
308 scm_port
*pt
= SCM_PTAB_ENTRY (port
);
310 if (pt
->rw_active
== SCM_PORT_WRITE
)
312 return scm_makfromstr ((char *) pt
->read_buf
, pt
->read_buf_size
, 0);
315 SCM_DEFINE (scm_object_to_string
, "object->string", 1, 1, 0,
316 (SCM obj
, SCM printer
),
317 "Return a Scheme string obtained by printing @var{obj}.\n"
318 "Printing function can be specified by the optional second\n"
319 "argument @var{printer} (default: @code{write}).")
320 #define FUNC_NAME s_scm_object_to_string
324 if (!SCM_UNBNDP (printer
))
325 SCM_VALIDATE_PROC (2, printer
);
327 str
= scm_makstr (0, 0);
328 port
= scm_mkstrport (SCM_INUM0
, str
, SCM_OPN
| SCM_WRTNG
, FUNC_NAME
);
330 if (SCM_UNBNDP (printer
))
331 scm_write (obj
, port
);
333 scm_apply (printer
, SCM_LIST2 (obj
, port
), SCM_EOL
);
335 return scm_strport_to_string (port
);
339 #if (SCM_DEBUG_DEPRECATED == 0)
342 scm_strprint_obj (SCM obj
)
344 return scm_object_to_string (obj
, SCM_UNDEFINED
);
347 #endif /* (SCM_DEBUG_DEPRECATED == 0) */
349 SCM_DEFINE (scm_call_with_output_string
, "call-with-output-string", 1, 0, 0,
351 "Calls the one-argument procedure @var{proc} with a newly created output\n"
352 "port. When the function returns, the string composed of the characters\n"
353 "written into the port is returned.")
354 #define FUNC_NAME s_scm_call_with_output_string
358 p
= scm_mkstrport (SCM_INUM0
,
359 scm_make_string (SCM_INUM0
, SCM_UNDEFINED
),
362 scm_apply (proc
, p
, scm_listofnull
);
364 return scm_strport_to_string (p
);
368 SCM_DEFINE (scm_call_with_input_string
, "call-with-input-string", 2, 0, 0,
370 "Calls the one-argument procedure @var{proc} with a newly created input\n"
371 "port from which @var{string}'s contents may be read. The value yielded\n"
372 "by the @var{proc} is returned.")
373 #define FUNC_NAME s_scm_call_with_input_string
375 SCM p
= scm_mkstrport(SCM_INUM0
, str
, SCM_OPN
| SCM_RDNG
, FUNC_NAME
);
376 return scm_apply (proc
, p
, scm_listofnull
);
382 /* Given a null-terminated string EXPR containing a Scheme expression
383 read it, and return it as an SCM value. */
385 scm_read_0str (char *expr
)
387 SCM port
= scm_mkstrport (SCM_INUM0
,
388 scm_makfrom0str (expr
),
393 /* Read expressions from that port; ignore the values. */
394 form
= scm_read (port
);
396 scm_close_port (port
);
400 /* Given a null-terminated string EXPR containing Scheme program text,
401 evaluate it, and return the result of the last expression evaluated. */
403 scm_eval_0str (const char *expr
)
405 return scm_eval_string (scm_makfrom0str (expr
));
409 SCM_DEFINE (scm_eval_string
, "eval-string", 1, 0, 0,
411 "Evaluate @var{string} as the text representation of a Scheme\n"
412 "form or forms, and return whatever value they produce.\n"
413 "Evaluation takes place in the environment returned by the\n"
414 "procedure @code{interaction-environment}.")
415 #define FUNC_NAME s_scm_eval_string
417 SCM port
= scm_mkstrport (SCM_INUM0
, string
, SCM_OPN
| SCM_RDNG
,
420 SCM ans
= SCM_UNSPECIFIED
;
421 SCM module
= scm_interaction_environment ();
423 /* Read expressions from that port; ignore the values. */
424 while (!SCM_EOF_OBJECT_P (form
= scm_read (port
)))
425 ans
= scm_eval_x (form
, module
);
427 /* Don't close the port here; if we re-enter this function via a
428 continuation, then the next time we enter it, we'll get an error.
429 It's a string port anyway, so there's no advantage to closing it
439 scm_bits_t tc
= scm_make_port_type ("string", stfill_buffer
, st_write
);
441 scm_set_port_mark (tc
, scm_markstream
);
442 scm_set_port_end_input (tc
, st_end_input
);
443 scm_set_port_flush (tc
, st_flush
);
444 scm_set_port_seek (tc
, st_seek
);
445 scm_set_port_truncate (tc
, st_truncate
);
453 scm_tc16_strport
= scm_make_stptob ();
455 #ifndef SCM_MAGIC_SNARFER
456 #include "libguile/strports.x"