1 /* Printing of backtraces and error messages
2 * Copyright (C) 1996,1997,1998,1999,2000,2001 Free Software Foundation
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2, or (at your option)
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this software; see the file COPYING. If not, write to
16 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
17 * Boston, MA 02111-1307 USA
19 * As a special exception, the Free Software Foundation gives permission
20 * for additional uses of the text contained in its release of GUILE.
22 * The exception is that, if you link the GUILE library with other files
23 * to produce an executable, this does not by itself cause the
24 * resulting executable to be covered by the GNU General Public License.
25 * Your use of that executable is in no way restricted on account of
26 * linking the GUILE library code into it.
28 * This exception does not however invalidate any other reasons why
29 * the executable file might be covered by the GNU General Public License.
31 * This exception applies only to the code released by the
32 * Free Software Foundation under the name GUILE. If you copy
33 * code from other Free Software Foundation releases into a copy of
34 * GUILE, as the General Public License permits, the exception does
35 * not apply to the code that you add in this way. To avoid misleading
36 * anyone as to the status of such modified files, you must delete
37 * this exception notice from them.
39 * If you write modifications of your own for GUILE, it is your choice
40 * whether to permit this exception to apply to your modifications.
41 * If you do not wish that, delete this exception notice.
43 * The author can be reached at djurfeldt@nada.kth.se
44 * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */
46 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
47 gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
52 #include "libguile/_scm.h"
58 #include "libguile/stacks.h"
59 #include "libguile/srcprop.h"
60 #include "libguile/struct.h"
61 #include "libguile/strports.h"
62 #include "libguile/throw.h"
63 #include "libguile/fluids.h"
64 #include "libguile/ports.h"
65 #include "libguile/strings.h"
67 #include "libguile/validate.h"
68 #include "libguile/backtrace.h"
69 #include "libguile/filesys.h"
71 /* {Error reporting and backtraces}
72 * (A first approximation.)
74 * Note that these functions shouldn't generate errors themselves.
79 #define SCM_ASSERT(_cond, _arg, _pos, _subr) \
84 SCM scm_the_last_stack_fluid_var
;
87 display_header (SCM source
, SCM port
)
89 if (SCM_MEMOIZEDP (source
))
91 SCM fname
= scm_source_property (source
, scm_sym_filename
);
92 SCM line
= scm_source_property (source
, scm_sym_line
);
93 SCM col
= scm_source_property (source
, scm_sym_column
);
95 /* Dirk:FIXME:: Maybe we should store the _port_ rather than the
96 * filename with the source properties? Then we could in case of
97 * non-file ports give at least some more details than just
98 * "<unnamed port>". */
99 if (SCM_STRINGP (fname
))
100 scm_prin1 (fname
, port
, 0);
102 scm_puts ("<unnamed port>", port
);
104 if (!SCM_FALSEP (line
) && !SCM_FALSEP (col
))
106 scm_putc (':', port
);
107 scm_intprint (SCM_INUM (line
) + 1, 10, port
);
108 scm_putc (':', port
);
109 scm_intprint (SCM_INUM (col
) + 1, 10, port
);
113 scm_puts ("ERROR", port
);
114 scm_puts (": ", port
);
119 scm_display_error_message (SCM message
, SCM args
, SCM port
)
121 if (SCM_STRINGP (message
) && !SCM_FALSEP (scm_list_p (args
)))
123 scm_simple_format (port
, message
, args
);
128 scm_display (message
, port
);
134 display_expression (SCM frame
,SCM pname
,SCM source
,SCM port
)
136 SCM print_state
= scm_make_print_state ();
137 scm_print_state
*pstate
= SCM_PRINT_STATE (print_state
);
138 pstate
->writingp
= 0;
142 if (SCM_SYMBOLP (pname
) || SCM_STRINGP (pname
))
144 if (SCM_FRAMEP (frame
)
145 && SCM_FRAME_EVAL_ARGS_P (frame
))
146 scm_puts ("While evaluating arguments to ", port
);
148 scm_puts ("In procedure ", port
);
149 scm_iprin1 (pname
, port
, pstate
);
150 if (SCM_MEMOIZEDP (source
))
152 scm_puts (" in expression ", port
);
153 pstate
->writingp
= 1;
154 scm_iprin1 (scm_unmemoize (source
), port
, pstate
);
157 else if (SCM_NIMP (source
))
159 scm_puts ("In expression ", port
);
160 pstate
->writingp
= 1;
161 scm_iprin1 (scm_unmemoize (source
), port
, pstate
);
163 scm_puts (":\n", port
);
164 scm_free_print_state (print_state
);
167 struct display_error_args
{
177 display_error_body (struct display_error_args
*a
)
179 SCM current_frame
= SCM_BOOL_F
;
180 SCM source
= SCM_BOOL_F
;
181 SCM prev_frame
= SCM_BOOL_F
;
185 && SCM_STACKP (a
->stack
)
186 && SCM_STACK_LENGTH (a
->stack
) > 0)
188 current_frame
= scm_stack_ref (a
->stack
, SCM_INUM0
);
189 source
= SCM_FRAME_SOURCE (current_frame
);
190 prev_frame
= SCM_FRAME_PREV (current_frame
);
191 if (!SCM_MEMOIZEDP (source
) && !SCM_FALSEP (prev_frame
))
192 source
= SCM_FRAME_SOURCE (prev_frame
);
193 if (!SCM_SYMBOLP (pname
) && !SCM_STRINGP (pname
) && SCM_FRAME_PROC_P (current_frame
)
194 && SCM_EQ_P (scm_procedure_p (SCM_FRAME_PROC (current_frame
)), SCM_BOOL_T
))
195 pname
= scm_procedure_name (SCM_FRAME_PROC (current_frame
));
197 if (SCM_SYMBOLP (pname
) || SCM_STRINGP (pname
) || SCM_MEMOIZEDP (source
))
199 display_header (source
, a
->port
);
200 display_expression (current_frame
, pname
, source
, a
->port
);
202 display_header (source
, a
->port
);
203 scm_display_error_message (a
->message
, a
->args
, a
->port
);
204 return SCM_UNSPECIFIED
;
207 struct display_error_handler_data
{
212 /* This is the exception handler for error reporting routines.
213 Note that it is very important that this handler *doesn't* try to
214 print more than the error tag, since the error very probably is
215 caused by an erroneous print call-back routine. If we would
216 try to print all objects, we would enter an infinite loop. */
218 display_error_handler (struct display_error_handler_data
*data
,
219 SCM tag
, SCM args SCM_UNUSED
)
221 SCM print_state
= scm_make_print_state ();
222 scm_puts ("\nException during displaying of ", data
->port
);
223 scm_puts (data
->mode
, data
->port
);
224 scm_puts (": ", data
->port
);
225 scm_iprin1 (tag
, data
->port
, SCM_PRINT_STATE (print_state
));
226 scm_putc ('\n', data
->port
);
227 return SCM_UNSPECIFIED
;
231 /* The function scm_i_display_error prints out a detailed error message. This
232 * function will be called directly within libguile to signal error messages.
233 * No parameter checks will be performed by scm_i_display_error. Thus, User
234 * code should rather use the function scm_display_error.
237 scm_i_display_error (SCM stack
, SCM port
, SCM subr
, SCM message
, SCM args
, SCM rest
)
239 struct display_error_args a
;
240 struct display_error_handler_data data
;
249 scm_internal_catch (SCM_BOOL_T
,
250 (scm_t_catch_body
) display_error_body
, &a
,
251 (scm_t_catch_handler
) display_error_handler
, &data
);
255 SCM_DEFINE (scm_display_error
, "display-error", 6, 0, 0,
256 (SCM stack
, SCM port
, SCM subr
, SCM message
, SCM args
, SCM rest
),
257 "Display an error message to the output port @var{port}.\n"
258 "@var{stack} is the saved stack for the error, @var{subr} is\n"
259 "the name of the procedure in which the error occured and\n"
260 "@var{message} is the actual error message, which may contain\n"
261 "formatting instructions. These will format the arguments in\n"
262 "the list @var{args} accordingly. @var{rest} is currently\n"
264 #define FUNC_NAME s_scm_display_error
266 SCM_VALIDATE_OUTPUT_PORT (2, port
);
268 scm_i_display_error (stack
, port
, subr
, message
, args
, rest
);
270 return SCM_UNSPECIFIED
;
280 static int n_print_params
= 9;
281 static print_params_t default_print_params
[] = {
285 { 1, 4 }, { 1, 3 }, { 1, 2 }
287 static print_params_t
*print_params
= default_print_params
;
290 SCM_DEFINE (scm_set_print_params_x
, "set-print-params!", 1, 0, 0,
292 "Set the print parameters to the values from @var{params}.\n"
293 "@var{params} must be a list of two-element lists which must\n"
294 "hold two integer values.")
295 #define FUNC_NAME s_scm_set_print_params_x
300 print_params_t
*new_params
;
302 SCM_VALIDATE_NONEMPTYLIST_COPYLEN (2, params
, n
);
303 for (ls
= params
; SCM_NNULLP (ls
); ls
= SCM_CDR (ls
))
304 SCM_ASSERT (scm_ilength (SCM_CAR (params
)) == 2
305 && SCM_INUMP (SCM_CAAR (ls
))
306 && SCM_INUM (SCM_CAAR (ls
)) >= 0
307 && SCM_INUMP (SCM_CADAR (ls
))
308 && SCM_INUM (SCM_CADAR (ls
)) >= 0,
311 s_scm_set_print_params_x
);
312 new_params
= scm_must_malloc (n
* sizeof (print_params_t
),
314 if (print_params
!= default_print_params
)
315 scm_must_free (print_params
);
316 print_params
= new_params
;
317 for (i
= 0; i
< n
; ++i
)
319 print_params
[i
].level
= SCM_INUM (SCM_CAAR (params
));
320 print_params
[i
].length
= SCM_INUM (SCM_CADAR (params
));
321 params
= SCM_CDR (params
);
324 return SCM_UNSPECIFIED
;
330 indent (int n
, SCM port
)
333 for (i
= 0; i
< n
; ++i
)
334 scm_putc (' ', port
);
338 display_frame_expr (char *hdr
,SCM exp
,char *tlr
,int indentation
,SCM sport
,SCM port
,scm_print_state
*pstate
)
342 scm_t_ptob_descriptor
*ptob
= scm_ptobs
+ SCM_PTOBNUM (sport
);
345 pstate
->length
= print_params
[i
].length
;
346 ptob
->seek (sport
, 0, SEEK_SET
);
349 pstate
->level
= print_params
[i
].level
- 1;
350 scm_iprlist (hdr
, exp
, tlr
[0], sport
, pstate
);
351 scm_puts (&tlr
[1], sport
);
355 pstate
->level
= print_params
[i
].level
;
356 scm_iprin1 (exp
, sport
, pstate
);
359 n
= ptob
->seek (sport
, 0, SEEK_CUR
);
362 while (indentation
+ n
> SCM_BACKTRACE_WIDTH
&& i
< n_print_params
);
363 ptob
->truncate (sport
, n
);
364 string
= scm_strport_to_string (sport
);
365 /* Remove control characters */
366 for (i
= 0; i
< n
; ++i
)
367 if (iscntrl (SCM_STRING_CHARS (string
)[i
]))
368 SCM_STRING_CHARS (string
)[i
] = ' ';
370 if (indentation
+ n
> SCM_BACKTRACE_WIDTH
)
372 n
= SCM_BACKTRACE_WIDTH
- indentation
;
373 SCM_STRING_CHARS (string
)[n
- 1] = '$';
376 scm_lfwrite (SCM_STRING_CHARS (string
), n
, port
);
380 display_application (SCM frame
,int indentation
,SCM sport
,SCM port
,scm_print_state
*pstate
)
382 SCM proc
= SCM_FRAME_PROC (frame
);
383 SCM name
= (SCM_NFALSEP (scm_procedure_p (proc
))
384 ? scm_procedure_name (proc
)
386 display_frame_expr ("[",
387 scm_cons (SCM_NFALSEP (name
) ? name
: proc
,
388 SCM_FRAME_ARGS (frame
)),
389 SCM_FRAME_EVAL_ARGS_P (frame
) ? " ..." : "]",
396 SCM_DEFINE (scm_display_application
, "display-application", 1, 2, 0,
397 (SCM frame
, SCM port
, SCM indent
),
398 "Display a procedure application @var{frame} to the output port\n"
399 "@var{port}. @var{indent} specifies the indentation of the\n"
401 #define FUNC_NAME s_scm_display_application
403 SCM_VALIDATE_FRAME (1,frame
);
404 if (SCM_UNBNDP (port
))
407 SCM_VALIDATE_OPOUTPORT (2,port
);
408 if (SCM_UNBNDP (indent
))
411 SCM_VALIDATE_INUM (3,indent
);
413 if (SCM_FRAME_PROC_P (frame
))
414 /* Display an application. */
416 SCM sport
, print_state
;
417 scm_print_state
*pstate
;
419 /* Create a string port used for adaptation of printing parameters. */
420 sport
= scm_mkstrport (SCM_INUM0
,
421 scm_make_string (SCM_MAKINUM (240),
426 /* Create a print state for printing of frames. */
427 print_state
= scm_make_print_state ();
428 pstate
= SCM_PRINT_STATE (print_state
);
429 pstate
->writingp
= 1;
432 display_application (frame
, SCM_INUM (indent
), sport
, port
, pstate
);
440 SCM_SYMBOL (sym_base
, "base");
443 display_backtrace_get_file_line (SCM frame
, SCM
*file
, SCM
*line
)
445 SCM source
= SCM_FRAME_SOURCE (frame
);
446 *file
= SCM_MEMOIZEDP (source
) ? scm_source_property (source
, scm_sym_filename
) : SCM_BOOL_F
;
447 *line
= (SCM_MEMOIZEDP (source
)) ? scm_source_property (source
, scm_sym_line
) : SCM_BOOL_F
;
451 display_backtrace_file (frame
, last_file
, port
, pstate
)
455 scm_print_state
*pstate
;
459 display_backtrace_get_file_line (frame
, &file
, &line
);
461 if (file
== *last_file
)
466 scm_puts ("In ", port
);
467 if (file
== SCM_BOOL_F
)
468 if (line
== SCM_BOOL_F
)
469 scm_puts ("unknown file", port
);
471 scm_puts ("current input", port
);
474 pstate
->writingp
= 0;
475 scm_iprin1 (file
, port
, pstate
);
476 pstate
->writingp
= 1;
478 scm_puts (":\n", port
);
482 display_backtrace_file_and_line (SCM frame
, SCM port
, scm_print_state
*pstate
)
486 display_backtrace_get_file_line (frame
, &file
, &line
);
488 if (SCM_EQ_P (SCM_SHOW_FILE_NAME
, sym_base
))
490 if (file
== SCM_BOOL_F
)
492 if (line
== SCM_BOOL_F
)
493 scm_putc ('?', port
);
495 scm_puts ("<stdin>", port
);
499 pstate
-> writingp
= 0;
500 scm_iprin1 (SCM_STRINGP (file
) ? scm_basename (file
, SCM_UNDEFINED
) : file
,
502 pstate
-> writingp
= 1;
505 scm_putc (':', port
);
507 else if (line
!= SCM_BOOL_F
)
510 for (i
= SCM_INUM (line
)+1; i
> 0; i
= i
/10, j
++)
515 if (line
== SCM_BOOL_F
)
516 scm_puts (" ?", port
);
518 scm_intprint (SCM_INUM (line
) + 1, 10, port
);
519 scm_puts (": ", port
);
523 display_frame (SCM frame
,int nfield
,int indentation
,SCM sport
,SCM port
,scm_print_state
*pstate
)
527 /* Announce missing frames? */
528 if (!SCM_BACKWARDS_P
&& SCM_FRAME_OVERFLOW_P (frame
))
530 indent (nfield
+ 1 + indentation
, port
);
531 scm_puts ("...\n", port
);
534 /* display file name and line number */
535 if (SCM_NFALSEP (SCM_SHOW_FILE_NAME
))
536 display_backtrace_file_and_line (frame
, port
, pstate
);
538 /* Check size of frame number. */
539 n
= SCM_FRAME_NUMBER (frame
);
540 for (i
= 0, j
= n
; j
> 0; ++i
) j
/= 10;
542 /* Number indentation. */
543 indent (nfield
- (i
? i
: 1), port
);
546 scm_iprin1 (SCM_MAKINUM (n
), port
, pstate
);
548 /* Real frame marker */
549 scm_putc (SCM_FRAME_REAL_P (frame
) ? '*' : ' ', port
);
552 indent (indentation
, port
);
554 if (SCM_FRAME_PROC_P (frame
))
555 /* Display an application. */
556 display_application (frame
, nfield
+ 1 + indentation
, sport
, port
, pstate
);
558 /* Display a special form. */
560 SCM source
= SCM_FRAME_SOURCE (frame
);
561 SCM copy
= (SCM_CONSP (source
)
562 ? scm_source_property (source
, scm_sym_copy
)
564 SCM umcopy
= (SCM_MEMOIZEDP (source
)
565 ? scm_unmemoize (source
)
567 display_frame_expr ("(",
568 SCM_CONSP (copy
) ? copy
: umcopy
,
570 nfield
+ 1 + indentation
,
575 scm_putc ('\n', port
);
577 /* Announce missing frames? */
578 if (SCM_BACKWARDS_P
&& SCM_FRAME_OVERFLOW_P (frame
))
580 indent (nfield
+ 1 + indentation
, port
);
581 scm_puts ("...\n", port
);
585 struct display_backtrace_args
{
593 display_backtrace_body(struct display_backtrace_args
*a
)
594 #define FUNC_NAME "display_backtrace_body"
596 int n_frames
, beg
, end
, n
, i
, j
;
597 int nfield
, indent_p
, indentation
;
598 SCM frame
, sport
, print_state
;
600 scm_print_state
*pstate
;
602 a
->port
= SCM_COERCE_OUTPORT (a
->port
);
604 /* Argument checking and extraction. */
605 SCM_ASSERT (SCM_STACKP (a
->stack
),
608 s_display_backtrace
);
609 SCM_ASSERT (SCM_OPOUTPORTP (a
->port
),
612 s_display_backtrace
);
613 n_frames
= SCM_INUM (scm_stack_length (a
->stack
));
614 n
= SCM_INUMP (a
->depth
) ? SCM_INUM (a
->depth
) : SCM_BACKTRACE_DEPTH
;
617 beg
= SCM_INUMP (a
->first
) ? SCM_INUM (a
->first
) : 0;
625 if (SCM_INUMP (a
->first
))
627 beg
= SCM_INUM (a
->first
);
641 SCM_ASSERT (beg
>= 0 && beg
< n_frames
, a
->first
, SCM_ARG3
, s_display_backtrace
);
642 SCM_ASSERT (n
> 0, a
->depth
, SCM_ARG4
, s_display_backtrace
);
644 /* Create a string port used for adaptation of printing parameters. */
645 sport
= scm_mkstrport (SCM_INUM0
,
646 scm_make_string (SCM_MAKINUM (240), SCM_UNDEFINED
),
650 /* Create a print state for printing of frames. */
651 print_state
= scm_make_print_state ();
652 pstate
= SCM_PRINT_STATE (print_state
);
653 pstate
->writingp
= 1;
656 /* First find out if it's reasonable to do indentation. */
662 frame
= scm_stack_ref (a
->stack
, SCM_MAKINUM (beg
));
663 for (i
= 0, j
= 0; i
< n
; ++i
)
665 if (SCM_FRAME_REAL_P (frame
))
667 if (j
> SCM_BACKTRACE_INDENT
)
672 frame
= (SCM_BACKWARDS_P
673 ? SCM_FRAME_PREV (frame
)
674 : SCM_FRAME_NEXT (frame
));
678 /* Determine size of frame number field. */
679 j
= SCM_FRAME_NUMBER (scm_stack_ref (a
->stack
, SCM_MAKINUM (end
)));
680 for (i
= 0; j
> 0; ++i
) j
/= 10;
684 frame
= scm_stack_ref (a
->stack
, SCM_MAKINUM (beg
));
686 last_file
= SCM_UNDEFINED
;
687 for (i
= 0; i
< n
; ++i
)
689 if (!SCM_EQ_P (SCM_SHOW_FILE_NAME
, sym_base
))
690 display_backtrace_file (frame
, &last_file
, a
->port
, pstate
);
692 display_frame (frame
, nfield
, indentation
, sport
, a
->port
, pstate
);
693 if (indent_p
&& SCM_FRAME_EVAL_ARGS_P (frame
))
695 frame
= (SCM_BACKWARDS_P
?
696 SCM_FRAME_PREV (frame
) : SCM_FRAME_NEXT (frame
));
699 scm_remember_upto_here_1 (print_state
);
701 return SCM_UNSPECIFIED
;
705 SCM_DEFINE (scm_display_backtrace
, "display-backtrace", 2, 2, 0,
706 (SCM stack
, SCM port
, SCM first
, SCM depth
),
707 "Display a backtrace to the output port @var{port}. @var{stack}\n"
708 "is the stack to take the backtrace from, @var{first} specifies\n"
709 "where in the stack to start and @var{depth} how much frames\n"
710 "to display. Both @var{first} and @var{depth} can be @code{#f},\n"
711 "which means that default values will be used.")
712 #define FUNC_NAME s_scm_display_backtrace
714 struct display_backtrace_args a
;
715 struct display_error_handler_data data
;
720 data
.mode
= "backtrace";
722 scm_internal_catch (SCM_BOOL_T
,
723 (scm_t_catch_body
) display_backtrace_body
, &a
,
724 (scm_t_catch_handler
) display_error_handler
, &data
);
725 return SCM_UNSPECIFIED
;
729 SCM_VARIABLE (scm_has_shown_backtrace_hint_p_var
, "has-shown-backtrace-hint?");
731 SCM_DEFINE (scm_backtrace
, "backtrace", 0, 0, 0,
733 "Display a backtrace of the stack saved by the last error\n"
734 "to the current output port.")
735 #define FUNC_NAME s_scm_backtrace
738 scm_fluid_ref (SCM_VARIABLE_REF (scm_the_last_stack_fluid_var
));
739 if (SCM_NFALSEP (the_last_stack
))
741 scm_newline (scm_cur_outp
);
742 scm_puts ("Backtrace:\n", scm_cur_outp
);
743 scm_display_backtrace (the_last_stack
,
747 scm_newline (scm_cur_outp
);
748 if (SCM_FALSEP (SCM_VARIABLE_REF (scm_has_shown_backtrace_hint_p_var
))
751 scm_puts ("Type \"(debug-enable 'backtrace)\" if you would like "
753 "automatically if an error occurs in the future.\n",
755 SCM_VARIABLE_SET (scm_has_shown_backtrace_hint_p_var
, SCM_BOOL_T
);
760 scm_puts ("No backtrace available.\n", scm_cur_outp
);
762 return SCM_UNSPECIFIED
;
769 scm_init_backtrace ()
771 SCM f
= scm_make_fluid ();
772 scm_the_last_stack_fluid_var
= scm_c_define ("the-last-stack", f
);
774 #ifndef SCM_MAGIC_SNARFER
775 #include "libguile/backtrace.x"