1 /* Copyright (C) 1995,1996,1998,1999,2000,2001 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.
83 scm_t_bits scm_tc16_strport
;
87 stfill_buffer (SCM port
)
89 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
91 if (pt
->read_pos
>= pt
->read_end
)
94 return scm_return_first_int (*pt
->read_pos
, port
);
97 /* change the size of a port's string to new_size. this doesn't
98 change read_buf_size. */
100 st_resize_port (scm_t_port
*pt
, off_t new_size
)
102 SCM old_stream
= SCM_PACK (pt
->stream
);
103 SCM new_stream
= scm_allocate_string (new_size
);
104 unsigned long int old_size
= SCM_STRING_LENGTH (old_stream
);
105 unsigned long int min_size
= min (old_size
, new_size
);
108 off_t index
= pt
->write_pos
- pt
->write_buf
;
110 pt
->write_buf_size
= new_size
;
112 for (i
= 0; i
!= min_size
; ++i
)
113 SCM_STRING_CHARS (new_stream
) [i
] = SCM_STRING_CHARS (old_stream
) [i
];
117 pt
->stream
= SCM_UNPACK (new_stream
);
118 pt
->read_buf
= pt
->write_buf
= SCM_STRING_UCHARS (new_stream
);
119 pt
->read_pos
= pt
->write_pos
= pt
->write_buf
+ index
;
120 pt
->write_end
= pt
->write_buf
+ pt
->write_buf_size
;
121 pt
->read_end
= pt
->read_buf
+ pt
->read_buf_size
;
125 /* amount by which write_buf is expanded. */
126 #define SCM_WRITE_BLOCK 80
128 /* ensure that write_pos < write_end by enlarging the buffer when
129 necessary. update read_buf to account for written chars. */
133 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
135 if (pt
->write_pos
== pt
->write_end
)
137 st_resize_port (pt
, pt
->write_buf_size
+ SCM_WRITE_BLOCK
);
139 pt
->read_pos
= pt
->write_pos
;
140 if (pt
->read_pos
> pt
->read_end
)
142 pt
->read_end
= (unsigned char *) pt
->read_pos
;
143 pt
->read_buf_size
= pt
->read_end
- pt
->read_buf
;
145 pt
->rw_active
= SCM_PORT_NEITHER
;
149 st_write (SCM port
, const void *data
, size_t size
)
151 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
152 const char *input
= (char *) data
;
156 int space
= pt
->write_end
- pt
->write_pos
;
157 int write_len
= (size
> space
) ? space
: size
;
159 strncpy ((char *) pt
->write_pos
, input
, write_len
);
160 pt
->write_pos
+= write_len
;
163 if (write_len
== space
)
169 st_end_input (SCM port
, int offset
)
171 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
173 if (pt
->read_pos
- pt
->read_buf
< offset
)
174 scm_misc_error ("st_end_input", "negative position", SCM_EOL
);
176 pt
->write_pos
= (unsigned char *) (pt
->read_pos
= pt
->read_pos
- offset
);
177 pt
->rw_active
= SCM_PORT_NEITHER
;
181 st_seek (SCM port
, off_t offset
, int whence
)
183 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
186 if (pt
->rw_active
== SCM_PORT_READ
&& offset
== 0 && whence
== SEEK_CUR
)
187 /* special case to avoid disturbing the unread-char buffer. */
189 if (pt
->read_buf
== pt
->putback_buf
)
191 target
= pt
->saved_read_pos
- pt
->saved_read_buf
192 - (pt
->read_end
- pt
->read_pos
);
196 target
= pt
->read_pos
- pt
->read_buf
;
200 /* all other cases. */
202 if (pt
->rw_active
== SCM_PORT_WRITE
)
205 if (pt
->rw_active
== SCM_PORT_READ
)
206 scm_end_input (port
);
211 target
= pt
->read_pos
- pt
->read_buf
+ offset
;
214 target
= pt
->read_end
- pt
->read_buf
+ offset
;
216 default: /* SEEK_SET */
222 scm_misc_error ("st_seek", "negative offset", SCM_EOL
);
224 if (target
>= pt
->write_buf_size
)
226 if (!(SCM_CELL_WORD_0 (port
) & SCM_WRTNG
))
228 if (target
> pt
->write_buf_size
)
230 scm_misc_error ("st_seek",
231 "seek past end of read-only strport",
237 st_resize_port (pt
, target
+ (target
== pt
->write_buf_size
242 pt
->read_pos
= pt
->write_pos
= pt
->read_buf
+ target
;
243 if (pt
->read_pos
> pt
->read_end
)
245 pt
->read_end
= (unsigned char *) pt
->read_pos
;
246 pt
->read_buf_size
= pt
->read_end
- pt
->read_buf
;
253 st_truncate (SCM port
, off_t length
)
255 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
257 if (length
> pt
->write_buf_size
)
258 st_resize_port (pt
, length
);
260 pt
->read_buf_size
= length
;
261 pt
->read_end
= pt
->read_buf
+ length
;
262 if (pt
->read_pos
> pt
->read_end
)
263 pt
->read_pos
= pt
->read_end
;
265 if (pt
->write_pos
> pt
->read_end
)
266 pt
->write_pos
= pt
->read_end
;
270 scm_mkstrport (SCM pos
, SCM str
, long modes
, const char *caller
)
276 SCM_ASSERT (SCM_INUMP(pos
) && SCM_INUM(pos
) >= 0, pos
, SCM_ARG1
, caller
);
277 SCM_ASSERT (SCM_STRINGP (str
), str
, SCM_ARG1
, caller
);
278 str_len
= SCM_STRING_LENGTH (str
);
279 if (SCM_INUM (pos
) > str_len
)
280 scm_out_of_range (caller
, pos
);
281 if (!((modes
& SCM_WRTNG
) || (modes
& SCM_RDNG
)))
282 scm_misc_error ("scm_mkstrport", "port must read or write", SCM_EOL
);
285 pt
= scm_add_to_port_table (z
);
286 SCM_SET_CELL_TYPE (z
, scm_tc16_strport
| modes
);
287 SCM_SETPTAB_ENTRY (z
, pt
);
288 SCM_SETSTREAM (z
, SCM_UNPACK (str
));
289 pt
->write_buf
= pt
->read_buf
= SCM_STRING_UCHARS (str
);
290 pt
->read_pos
= pt
->write_pos
= pt
->read_buf
+ SCM_INUM (pos
);
291 pt
->write_buf_size
= pt
->read_buf_size
= str_len
;
292 pt
->write_end
= pt
->read_end
= pt
->read_buf
+ pt
->read_buf_size
;
298 /* ensure write_pos is writable. */
299 if ((modes
& SCM_WRTNG
) && pt
->write_pos
== pt
->write_end
)
304 /* create a new string from a string port's buffer. */
305 SCM
scm_strport_to_string (SCM port
)
307 scm_t_port
*pt
= SCM_PTAB_ENTRY (port
);
310 if (pt
->rw_active
== SCM_PORT_WRITE
)
313 str
= scm_mem2string ((char *) pt
->read_buf
, pt
->read_buf_size
);
314 scm_remember_upto_here_1 (port
);
318 SCM_DEFINE (scm_object_to_string
, "object->string", 1, 1, 0,
319 (SCM obj
, SCM printer
),
320 "Return a Scheme string obtained by printing @var{obj}.\n"
321 "Printing function can be specified by the optional second\n"
322 "argument @var{printer} (default: @code{write}).")
323 #define FUNC_NAME s_scm_object_to_string
327 if (!SCM_UNBNDP (printer
))
328 SCM_VALIDATE_PROC (2, printer
);
330 str
= scm_allocate_string (0);
331 port
= scm_mkstrport (SCM_INUM0
, str
, SCM_OPN
| SCM_WRTNG
, FUNC_NAME
);
333 if (SCM_UNBNDP (printer
))
334 scm_write (obj
, port
);
336 scm_apply (printer
, SCM_LIST2 (obj
, port
), SCM_EOL
);
338 return scm_strport_to_string (port
);
342 #if (SCM_DEBUG_DEPRECATED == 0)
345 scm_strprint_obj (SCM obj
)
347 return scm_object_to_string (obj
, SCM_UNDEFINED
);
350 #endif /* (SCM_DEBUG_DEPRECATED == 0) */
352 SCM_DEFINE (scm_call_with_output_string
, "call-with-output-string", 1, 0, 0,
354 "Calls the one-argument procedure @var{proc} with a newly created output\n"
355 "port. When the function returns, the string composed of the characters\n"
356 "written into the port is returned.")
357 #define FUNC_NAME s_scm_call_with_output_string
361 p
= scm_mkstrport (SCM_INUM0
,
362 scm_make_string (SCM_INUM0
, SCM_UNDEFINED
),
365 scm_apply (proc
, p
, scm_listofnull
);
367 return scm_strport_to_string (p
);
371 SCM_DEFINE (scm_call_with_input_string
, "call-with-input-string", 2, 0, 0,
372 (SCM string
, SCM proc
),
373 "Calls the one-argument procedure @var{proc} with a newly\n"
374 "created input port from which @var{string}'s contents may be\n"
375 "read. The value yielded by the @var{proc} is returned.")
376 #define FUNC_NAME s_scm_call_with_input_string
378 SCM p
= scm_mkstrport(SCM_INUM0
, string
, SCM_OPN
| SCM_RDNG
, FUNC_NAME
);
379 return scm_apply (proc
, p
, scm_listofnull
);
383 SCM_DEFINE (scm_open_input_string
, "open-input-string", 1, 0, 0,
385 "Take a string and return an input port that delivers characters\n"
386 "from the string. The port can be closed by\n"
387 "@code{close-input-port}, though its storage will be reclaimed\n"
388 "by the garbage collector if it becomes inaccessible.")
389 #define FUNC_NAME s_scm_open_input_string
391 SCM p
= scm_mkstrport(SCM_INUM0
, str
, SCM_OPN
| SCM_RDNG
, FUNC_NAME
);
396 SCM_DEFINE (scm_open_output_string
, "open-output-string", 0, 0, 0,
398 "Return an output port that will accumulate characters for\n"
399 "retrieval by @code{get-output-string}. The port can be closed\n"
400 "by the procedure @code{close-output-port}, though its storage\n"
401 "will be reclaimed by the garbage collector if it becomes\n"
403 #define FUNC_NAME s_scm_open_output_string
407 p
= scm_mkstrport (SCM_INUM0
,
408 scm_make_string (SCM_INUM0
, SCM_UNDEFINED
),
415 SCM_DEFINE (scm_get_output_string
, "get-output-string", 1, 0, 0,
417 "Given an output port created by @code{open-output-string},\n"
418 "return a string consisting of the characters that have been\n"
419 "output to the port so far.")
420 #define FUNC_NAME s_scm_get_output_string
422 SCM_VALIDATE_OPOUTSTRPORT (1, port
);
423 return scm_strport_to_string (port
);
428 /* Given a null-terminated string EXPR containing a Scheme expression
429 read it, and return it as an SCM value. */
431 scm_read_0str (char *expr
)
433 SCM port
= scm_mkstrport (SCM_INUM0
,
434 scm_makfrom0str (expr
),
439 /* Read expressions from that port; ignore the values. */
440 form
= scm_read (port
);
442 scm_close_port (port
);
446 /* Given a null-terminated string EXPR containing Scheme program text,
447 evaluate it, and return the result of the last expression evaluated. */
449 scm_eval_0str (const char *expr
)
451 return scm_eval_string (scm_makfrom0str (expr
));
455 inner_eval_string (void *data
)
457 SCM port
= (SCM
)data
;
459 SCM ans
= SCM_UNSPECIFIED
;
461 /* Read expressions from that port; ignore the values. */
462 while (!SCM_EOF_OBJECT_P (form
= scm_read (port
)))
463 ans
= scm_primitive_eval_x (form
);
465 /* Don't close the port here; if we re-enter this function via a
466 continuation, then the next time we enter it, we'll get an error.
467 It's a string port anyway, so there's no advantage to closing it
473 SCM_DEFINE (scm_eval_string
, "eval-string", 1, 0, 0,
475 "Evaluate @var{string} as the text representation of a Scheme\n"
476 "form or forms, and return whatever value they produce.\n"
477 "Evaluation takes place in the environment returned by the\n"
478 "procedure @code{interaction-environment}.")
479 #define FUNC_NAME s_scm_eval_string
481 SCM port
= scm_mkstrport (SCM_INUM0
, string
, SCM_OPN
| SCM_RDNG
,
483 return scm_c_call_with_current_module (scm_interaction_environment (),
484 inner_eval_string
, (void *)port
);
491 scm_t_bits tc
= scm_make_port_type ("string", stfill_buffer
, st_write
);
493 scm_set_port_mark (tc
, scm_markstream
);
494 scm_set_port_end_input (tc
, st_end_input
);
495 scm_set_port_flush (tc
, st_flush
);
496 scm_set_port_seek (tc
, st_seek
);
497 scm_set_port_truncate (tc
, st_truncate
);
505 scm_tc16_strport
= scm_make_stptob ();
507 #ifndef SCM_MAGIC_SNARFER
508 #include "libguile/strports.x"