1 /* Printing of backtraces and error messages
2 * Copyright (C) 1996,1997,1998,1999,2000,2001, 2003, 2004, 2006, 2009, 2010, 2011 Free Software Foundation
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public License
6 * as published by the Free Software Foundation; either version 3 of
7 * the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
27 #include "libguile/_scm.h"
36 #include "libguile/deprecation.h"
37 #include "libguile/stacks.h"
38 #include "libguile/srcprop.h"
39 #include "libguile/struct.h"
40 #include "libguile/strports.h"
41 #include "libguile/throw.h"
42 #include "libguile/fluids.h"
43 #include "libguile/ports.h"
44 #include "libguile/strings.h"
45 #include "libguile/dynwind.h"
46 #include "libguile/frames.h"
48 #include "libguile/validate.h"
49 #include "libguile/backtrace.h"
50 #include "libguile/filesys.h"
51 #include "libguile/private-options.h"
53 /* {Error reporting and backtraces}
55 * Note that these functions shouldn't generate errors themselves.
59 boot_print_exception (SCM port
, SCM frame
, SCM key
, SCM args
)
60 #define FUNC_NAME "boot-print-exception"
62 scm_puts ("Throw to key ", port
);
63 scm_write (key
, port
);
64 scm_puts (" with args ", port
);
65 scm_write (args
, port
);
66 return SCM_UNSPECIFIED
;
71 scm_print_exception (SCM port
, SCM frame
, SCM key
, SCM args
)
72 #define FUNC_NAME "print-exception"
74 static SCM print_exception
= SCM_BOOL_F
;
76 SCM_VALIDATE_OPOUTPORT (1, port
);
77 if (scm_is_true (frame
))
78 SCM_VALIDATE_FRAME (2, frame
);
79 SCM_VALIDATE_SYMBOL (3, key
);
80 SCM_VALIDATE_LIST (4, args
);
82 if (scm_is_false (print_exception
))
84 scm_module_variable (scm_the_root_module (),
85 scm_from_latin1_symbol ("print-exception"));
87 return scm_call_4 (scm_variable_ref (print_exception
),
88 port
, frame
, key
, args
);
95 /* Print parameters for error messages. */
97 #define DISPLAY_ERROR_MESSAGE_MAX_LEVEL 7
98 #define DISPLAY_ERROR_MESSAGE_MAX_LENGTH 10
100 /* Print parameters for failing expressions in error messages.
101 * (See also `print_params' below for backtrace print parameters.)
104 #define DISPLAY_EXPRESSION_MAX_LEVEL 2
105 #define DISPLAY_EXPRESSION_MAX_LENGTH 3
108 #define SCM_ASSERT(_cond, _arg, _pos, _subr) \
114 scm_display_error_message (SCM message
, SCM args
, SCM port
)
116 scm_print_exception (port
, SCM_BOOL_F
, scm_misc_error_key
,
117 scm_list_3 (SCM_BOOL_F
, message
, args
));
121 /* The function scm_i_display_error prints out a detailed error message. This
122 * function will be called directly within libguile to signal error messages.
123 * No parameter checks will be performed by scm_i_display_error. Thus, User
124 * code should rather use the function scm_display_error.
127 scm_i_display_error (SCM frame
, SCM port
, SCM subr
, SCM message
, SCM args
, SCM rest
)
129 scm_print_exception (port
, frame
, scm_misc_error_key
,
130 scm_list_3 (subr
, message
, args
));
134 SCM_DEFINE (scm_display_error
, "display-error", 6, 0, 0,
135 (SCM frame
, SCM port
, SCM subr
, SCM message
, SCM args
, SCM rest
),
136 "Display an error message to the output port @var{port}.\n"
137 "@var{frame} is the frame in which the error occurred, @var{subr} is\n"
138 "the name of the procedure in which the error occurred and\n"
139 "@var{message} is the actual error message, which may contain\n"
140 "formatting instructions. These will format the arguments in\n"
141 "the list @var{args} accordingly. @var{rest} is currently\n"
143 #define FUNC_NAME s_scm_display_error
145 SCM_VALIDATE_OUTPUT_PORT (2, port
);
147 scm_i_display_error (frame
, port
, subr
, message
, args
, rest
);
149 return SCM_UNSPECIFIED
;
159 static int n_print_params
= 9;
160 static print_params_t default_print_params
[] = {
164 { 1, 4 }, { 1, 3 }, { 1, 2 }
166 static print_params_t
*print_params
= default_print_params
;
169 SCM_DEFINE (scm_set_print_params_x
, "set-print-params!", 1, 0, 0,
171 "Set the print parameters to the values from @var{params}.\n"
172 "@var{params} must be a list of two-element lists which must\n"
173 "hold two integer values.")
174 #define FUNC_NAME s_scm_set_print_params_x
179 print_params_t
*new_params
;
181 SCM_VALIDATE_NONEMPTYLIST_COPYLEN (2, params
, n
);
182 for (ls
= params
; !SCM_NULL_OR_NIL_P (ls
); ls
= SCM_CDR (ls
))
183 SCM_ASSERT (scm_ilength (SCM_CAR (params
)) == 2
184 && scm_is_unsigned_integer (SCM_CAAR (ls
), 0, INT_MAX
)
185 && scm_is_unsigned_integer (SCM_CADAR (ls
), 0, INT_MAX
),
188 s_scm_set_print_params_x
);
189 new_params
= scm_malloc (n
* sizeof (print_params_t
));
190 if (print_params
!= default_print_params
)
192 print_params
= new_params
;
193 for (i
= 0; i
< n
; ++i
)
195 print_params
[i
].level
= scm_to_int (SCM_CAAR (params
));
196 print_params
[i
].length
= scm_to_int (SCM_CADAR (params
));
197 params
= SCM_CDR (params
);
200 return SCM_UNSPECIFIED
;
206 indent (int n
, SCM port
)
209 for (i
= 0; i
< n
; ++i
)
210 scm_putc (' ', port
);
214 display_frame_expr (char *hdr
, SCM exp
, char *tlr
, int indentation
, SCM sport
, SCM port
, scm_print_state
*pstate
)
217 scm_t_ptob_descriptor
*ptob
= scm_ptobs
+ SCM_PTOBNUM (sport
);
220 pstate
->length
= print_params
[i
].length
;
221 ptob
->seek (sport
, 0, SEEK_SET
);
222 if (scm_is_pair (exp
))
224 pstate
->level
= print_params
[i
].level
- 1;
225 scm_iprlist (hdr
, exp
, tlr
[0], sport
, pstate
);
226 scm_puts (&tlr
[1], sport
);
230 pstate
->level
= print_params
[i
].level
;
231 scm_iprin1 (exp
, sport
, pstate
);
234 n
= ptob
->seek (sport
, 0, SEEK_CUR
);
237 while (indentation
+ n
> SCM_BACKTRACE_WIDTH
&& i
< n_print_params
);
238 ptob
->truncate (sport
, n
);
240 scm_display (scm_strport_to_string (sport
), port
);
244 display_application (SCM frame
, int indentation
, SCM sport
, SCM port
, scm_print_state
*pstate
)
246 SCM proc
= scm_frame_procedure (frame
);
247 SCM name
= (scm_is_true (scm_procedure_p (proc
))
248 ? scm_procedure_name (proc
)
250 display_frame_expr ("[",
251 scm_cons (scm_is_true (name
) ? name
: proc
,
252 scm_frame_arguments (frame
)),
260 SCM_DEFINE (scm_display_application
, "display-application", 1, 2, 0,
261 (SCM frame
, SCM port
, SCM indent
),
262 "Display a procedure application @var{frame} to the output port\n"
263 "@var{port}. @var{indent} specifies the indentation of the\n"
265 #define FUNC_NAME s_scm_display_application
267 SCM_VALIDATE_FRAME (1, frame
);
268 if (SCM_UNBNDP (port
))
269 port
= scm_current_output_port ();
271 SCM_VALIDATE_OPOUTPORT (2, port
);
272 if (SCM_UNBNDP (indent
))
275 /* Display an application. */
277 SCM sport
, print_state
;
278 scm_print_state
*pstate
;
280 /* Create a string port used for adaptation of printing parameters. */
281 sport
= scm_mkstrport (SCM_INUM0
, SCM_BOOL_F
,
285 /* Create a print state for printing of frames. */
286 print_state
= scm_make_print_state ();
287 pstate
= SCM_PRINT_STATE (print_state
);
288 pstate
->writingp
= 1;
291 display_application (frame
, scm_to_int (indent
), sport
, port
, pstate
);
297 SCM_SYMBOL (sym_base
, "base");
300 display_backtrace_get_file_line (SCM frame
, SCM
*file
, SCM
*line
)
302 SCM source
= scm_frame_source (frame
);
303 *file
= *line
= SCM_BOOL_F
;
304 if (scm_is_pair (source
)
305 && scm_is_pair (scm_cdr (source
))
306 && scm_is_pair (scm_cddr (source
))
307 && !scm_is_pair (scm_cdddr (source
)))
309 /* (addr . (filename . (line . column))), from vm compilation */
310 *file
= scm_cadr (source
);
311 *line
= scm_caddr (source
);
316 display_backtrace_file (frame
, last_file
, port
, pstate
)
320 scm_print_state
*pstate
;
324 display_backtrace_get_file_line (frame
, &file
, &line
);
326 if (scm_is_true (scm_equal_p (file
, *last_file
)))
331 scm_puts ("In ", port
);
332 if (scm_is_false (file
))
333 if (scm_is_false (line
))
334 scm_puts ("unknown file", port
);
336 scm_puts ("current input", port
);
339 pstate
->writingp
= 0;
340 scm_iprin1 (file
, port
, pstate
);
341 pstate
->writingp
= 1;
343 scm_puts (":\n", port
);
347 display_backtrace_file_and_line (SCM frame
, SCM port
, scm_print_state
*pstate
)
351 display_backtrace_get_file_line (frame
, &file
, &line
);
353 if (scm_is_eq (SCM_PACK (SCM_SHOW_FILE_NAME
), sym_base
))
355 if (scm_is_false (file
))
357 if (scm_is_false (line
))
358 scm_putc ('?', port
);
360 scm_puts ("<stdin>", port
);
364 pstate
-> writingp
= 0;
366 scm_iprin1 ((scm_is_string (file
)?
367 scm_basename (file
, SCM_UNDEFINED
) : file
),
370 scm_iprin1 (file
, port
, pstate
);
372 pstate
-> writingp
= 1;
375 scm_putc (':', port
);
377 else if (scm_is_true (line
))
380 for (i
= scm_to_int (line
)+1; i
> 0; i
= i
/10, j
++)
385 if (scm_is_false (line
))
386 scm_puts (" ?", port
);
388 scm_intprint (scm_to_int (line
) + 1, 10, port
);
389 scm_puts (": ", port
);
393 display_frame (SCM frame
, int n
, int nfield
, int indentation
,
394 SCM sport
, SCM port
, scm_print_state
*pstate
)
398 /* display file name and line number */
399 if (scm_is_true (SCM_PACK (SCM_SHOW_FILE_NAME
)))
400 display_backtrace_file_and_line (frame
, port
, pstate
);
402 /* Check size of frame number. */
403 for (i
= 0, j
= n
; j
> 0; ++i
) j
/= 10;
405 /* Number indentation. */
406 indent (nfield
- (i
? i
: 1), port
);
409 scm_iprin1 (scm_from_int (n
), port
, pstate
);
412 indent (indentation
, port
);
414 /* Display an application. */
415 display_application (frame
, nfield
+ 1 + indentation
, sport
, port
, pstate
);
416 scm_putc ('\n', port
);
419 struct display_backtrace_args
{
424 SCM highlight_objects
;
428 display_backtrace_body (struct display_backtrace_args
*a
)
429 #define FUNC_NAME "display_backtrace_body"
431 int n_frames
, beg
, end
, n
, i
, j
;
432 int nfield
, indent_p
, indentation
;
433 SCM frame
, sport
, print_state
;
435 scm_print_state
*pstate
;
437 a
->port
= SCM_COERCE_OUTPORT (a
->port
);
439 /* Argument checking and extraction. */
440 SCM_VALIDATE_STACK (1, a
->stack
);
441 SCM_VALIDATE_OPOUTPORT (2, a
->port
);
442 n_frames
= scm_to_int (scm_stack_length (a
->stack
));
443 n
= scm_is_integer (a
->depth
) ? scm_to_int (a
->depth
) : SCM_BACKTRACE_DEPTH
;
446 beg
= scm_is_integer (a
->first
) ? scm_to_int (a
->first
) : 0;
454 if (scm_is_integer (a
->first
))
456 beg
= scm_to_int (a
->first
);
470 SCM_ASSERT (beg
>= 0 && beg
< n_frames
, a
->first
, SCM_ARG3
, s_display_backtrace
);
471 SCM_ASSERT (n
> 0, a
->depth
, SCM_ARG4
, s_display_backtrace
);
473 /* Create a string port used for adaptation of printing parameters. */
474 sport
= scm_mkstrport (SCM_INUM0
, SCM_BOOL_F
,
478 /* Create a print state for printing of frames. */
479 print_state
= scm_make_print_state ();
480 pstate
= SCM_PRINT_STATE (print_state
);
481 pstate
->writingp
= 1;
483 pstate
->highlight_objects
= a
->highlight_objects
;
485 /* First find out if it's reasonable to do indentation. */
488 /* Determine size of frame number field. */
490 for (i
= 0; j
> 0; ++i
) j
/= 10;
495 last_file
= SCM_UNDEFINED
;
500 for (i
= beg
; i
!= end
; SCM_BACKWARDS_P
? ++i
: --i
)
502 frame
= scm_stack_ref (a
->stack
, scm_from_int (i
));
503 if (!scm_is_eq (SCM_PACK (SCM_SHOW_FILE_NAME
), sym_base
))
504 display_backtrace_file (frame
, &last_file
, a
->port
, pstate
);
505 display_frame (frame
, i
, nfield
, indentation
, sport
, a
->port
, pstate
);
508 scm_remember_upto_here_1 (print_state
);
510 return SCM_UNSPECIFIED
;
515 error_during_backtrace (void *data
, SCM tag
, SCM throw_args
)
517 SCM port
= PTR2SCM (data
);
519 scm_puts ("Exception thrown while printing backtrace:\n", port
);
520 scm_print_exception (port
, SCM_BOOL_F
, tag
, throw_args
);
522 return SCM_UNSPECIFIED
;
526 SCM_DEFINE (scm_display_backtrace_with_highlights
, "display-backtrace", 2, 3, 0,
527 (SCM stack
, SCM port
, SCM first
, SCM depth
, SCM highlights
),
528 "Display a backtrace to the output port @var{port}. @var{stack}\n"
529 "is the stack to take the backtrace from, @var{first} specifies\n"
530 "where in the stack to start and @var{depth} how many frames\n"
531 "to display. @var{first} and @var{depth} can be @code{#f},\n"
532 "which means that default values will be used.\n"
533 "If @var{highlights} is given it should be a list; the elements\n"
534 "of this list will be highlighted wherever they appear in the\n"
536 #define FUNC_NAME s_scm_display_backtrace_with_highlights
538 struct display_backtrace_args a
;
543 if (SCM_UNBNDP (highlights
))
544 a
.highlight_objects
= SCM_EOL
;
546 a
.highlight_objects
= highlights
;
548 scm_internal_catch (SCM_BOOL_T
,
549 (scm_t_catch_body
) display_backtrace_body
, &a
,
550 (scm_t_catch_handler
) error_during_backtrace
, SCM2PTR (port
));
552 return SCM_UNSPECIFIED
;
557 scm_display_backtrace (SCM stack
, SCM port
, SCM first
, SCM depth
)
559 return scm_display_backtrace_with_highlights (stack
, port
, first
, depth
,
563 SCM_VARIABLE (scm_has_shown_backtrace_hint_p_var
, "has-shown-backtrace-hint?");
565 SCM_DEFINE (scm_backtrace_with_highlights
, "backtrace", 0, 1, 0,
567 "Display a backtrace of the current stack to the current\n"
568 "output port. If @var{highlights} is given, it should be\n"
569 "a list; the elements of this list will be highlighted\n"
570 "wherever they appear in the backtrace.")
571 #define FUNC_NAME s_scm_backtrace_with_highlights
573 SCM port
= scm_current_output_port ();
574 SCM stack
= scm_make_stack (SCM_BOOL_T
, SCM_EOL
);
576 if (SCM_UNBNDP (highlights
))
577 highlights
= SCM_EOL
;
580 scm_puts ("Backtrace:\n", port
);
581 scm_display_backtrace_with_highlights (stack
, port
, SCM_BOOL_F
, SCM_BOOL_F
,
585 return SCM_UNSPECIFIED
;
592 return scm_backtrace_with_highlights (SCM_EOL
);
598 scm_init_backtrace ()
600 scm_c_define_gsubr ("print-exception", 4, 0, 0, boot_print_exception
);
601 #include "libguile/backtrace.x"