| 1 | /* Printing of backtraces and error messages |
| 2 | * Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation |
| 3 | * |
| 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) |
| 7 | * any later version. |
| 8 | * |
| 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. |
| 13 | * |
| 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 |
| 18 | * |
| 19 | * As a special exception, the Free Software Foundation gives permission |
| 20 | * for additional uses of the text contained in its release of GUILE. |
| 21 | * |
| 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. |
| 27 | * |
| 28 | * This exception does not however invalidate any other reasons why |
| 29 | * the executable file might be covered by the GNU General Public License. |
| 30 | * |
| 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. |
| 38 | * |
| 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. |
| 42 | * |
| 43 | * The author can be reached at djurfeldt@nada.kth.se |
| 44 | * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */ |
| 45 | |
| 46 | /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999, |
| 47 | gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */ |
| 48 | |
| 49 | |
| 50 | #include <ctype.h> |
| 51 | |
| 52 | #include "libguile/_scm.h" |
| 53 | |
| 54 | #ifdef HAVE_UNISTD_H |
| 55 | #include <unistd.h> |
| 56 | #endif |
| 57 | |
| 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" |
| 66 | |
| 67 | #include "libguile/validate.h" |
| 68 | #include "libguile/backtrace.h" |
| 69 | |
| 70 | /* {Error reporting and backtraces} |
| 71 | * (A first approximation.) |
| 72 | * |
| 73 | * Note that these functions shouldn't generate errors themselves. |
| 74 | */ |
| 75 | |
| 76 | #ifndef SCM_RECKLESS |
| 77 | #undef SCM_ASSERT |
| 78 | #define SCM_ASSERT(_cond, _arg, _pos, _subr) \ |
| 79 | if (!(_cond)) \ |
| 80 | return SCM_BOOL_F; |
| 81 | #endif |
| 82 | |
| 83 | SCM scm_the_last_stack_fluid_var; |
| 84 | |
| 85 | static void |
| 86 | display_header (SCM source, SCM port) |
| 87 | { |
| 88 | if (SCM_MEMOIZEDP (source)) |
| 89 | { |
| 90 | SCM fname = scm_source_property (source, scm_sym_filename); |
| 91 | SCM line = scm_source_property (source, scm_sym_line); |
| 92 | SCM col = scm_source_property (source, scm_sym_column); |
| 93 | |
| 94 | /* Dirk:FIXME:: Maybe we should store the _port_ rather than the |
| 95 | * filename with the source properties? Then we could in case of |
| 96 | * non-file ports give at least some more details than just |
| 97 | * "<unnamed port>". */ |
| 98 | if (SCM_STRINGP (fname)) |
| 99 | scm_prin1 (fname, port, 0); |
| 100 | else |
| 101 | scm_puts ("<unnamed port>", port); |
| 102 | |
| 103 | if (!SCM_FALSEP (line) && !SCM_FALSEP (col)) |
| 104 | { |
| 105 | scm_putc (':', port); |
| 106 | scm_intprint (SCM_INUM (line) + 1, 10, port); |
| 107 | scm_putc (':', port); |
| 108 | scm_intprint (SCM_INUM (col) + 1, 10, port); |
| 109 | } |
| 110 | } |
| 111 | else |
| 112 | scm_puts ("ERROR", port); |
| 113 | scm_puts (": ", port); |
| 114 | } |
| 115 | |
| 116 | |
| 117 | void |
| 118 | scm_display_error_message (SCM message, SCM args, SCM port) |
| 119 | { |
| 120 | if (SCM_STRINGP (message) && !SCM_FALSEP (scm_list_p (args))) |
| 121 | { |
| 122 | scm_simple_format (port, message, args); |
| 123 | scm_newline (port); |
| 124 | } |
| 125 | else |
| 126 | { |
| 127 | scm_display (message, port); |
| 128 | scm_newline (port); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | static void |
| 133 | display_expression (SCM frame,SCM pname,SCM source,SCM port) |
| 134 | { |
| 135 | SCM print_state = scm_make_print_state (); |
| 136 | scm_print_state *pstate = SCM_PRINT_STATE (print_state); |
| 137 | pstate->writingp = 0; |
| 138 | pstate->fancyp = 1; |
| 139 | pstate->level = 2; |
| 140 | pstate->length = 3; |
| 141 | if (SCM_SYMBOLP (pname) || SCM_STRINGP (pname)) |
| 142 | { |
| 143 | if (SCM_FRAMEP (frame) |
| 144 | && SCM_FRAME_EVAL_ARGS_P (frame)) |
| 145 | scm_puts ("While evaluating arguments to ", port); |
| 146 | else |
| 147 | scm_puts ("In procedure ", port); |
| 148 | scm_iprin1 (pname, port, pstate); |
| 149 | if (SCM_MEMOIZEDP (source)) |
| 150 | { |
| 151 | scm_puts (" in expression ", port); |
| 152 | pstate->writingp = 1; |
| 153 | scm_iprin1 (scm_unmemoize (source), port, pstate); |
| 154 | } |
| 155 | } |
| 156 | else if (SCM_NIMP (source)) |
| 157 | { |
| 158 | scm_puts ("In expression ", port); |
| 159 | pstate->writingp = 1; |
| 160 | scm_iprin1 (scm_unmemoize (source), port, pstate); |
| 161 | } |
| 162 | scm_puts (":\n", port); |
| 163 | scm_free_print_state (print_state); |
| 164 | } |
| 165 | |
| 166 | struct display_error_args { |
| 167 | SCM stack; |
| 168 | SCM port; |
| 169 | SCM subr; |
| 170 | SCM message; |
| 171 | SCM args; |
| 172 | SCM rest; |
| 173 | }; |
| 174 | |
| 175 | static SCM |
| 176 | display_error_body (struct display_error_args *a) |
| 177 | { |
| 178 | SCM current_frame = SCM_BOOL_F; |
| 179 | SCM source = SCM_BOOL_F; |
| 180 | SCM prev_frame = SCM_BOOL_F; |
| 181 | SCM pname = a->subr; |
| 182 | |
| 183 | if (SCM_DEBUGGINGP |
| 184 | && SCM_STACKP (a->stack) |
| 185 | && SCM_STACK_LENGTH (a->stack) > 0) |
| 186 | { |
| 187 | current_frame = scm_stack_ref (a->stack, SCM_INUM0); |
| 188 | source = SCM_FRAME_SOURCE (current_frame); |
| 189 | prev_frame = SCM_FRAME_PREV (current_frame); |
| 190 | if (!SCM_MEMOIZEDP (source) && !SCM_FALSEP (prev_frame)) |
| 191 | source = SCM_FRAME_SOURCE (prev_frame); |
| 192 | if (!SCM_SYMBOLP (pname) && !SCM_STRINGP (pname) && SCM_FRAME_PROC_P (current_frame) |
| 193 | && SCM_EQ_P (scm_procedure_p (SCM_FRAME_PROC (current_frame)), SCM_BOOL_T)) |
| 194 | pname = scm_procedure_name (SCM_FRAME_PROC (current_frame)); |
| 195 | } |
| 196 | if (SCM_SYMBOLP (pname) || SCM_STRINGP (pname) || SCM_MEMOIZEDP (source)) |
| 197 | { |
| 198 | display_header (source, a->port); |
| 199 | display_expression (current_frame, pname, source, a->port); |
| 200 | } |
| 201 | display_header (source, a->port); |
| 202 | scm_display_error_message (a->message, a->args, a->port); |
| 203 | return SCM_UNSPECIFIED; |
| 204 | } |
| 205 | |
| 206 | struct display_error_handler_data { |
| 207 | char *mode; |
| 208 | SCM port; |
| 209 | }; |
| 210 | |
| 211 | /* This is the exception handler for error reporting routines. |
| 212 | Note that it is very important that this handler *doesn't* try to |
| 213 | print more than the error tag, since the error very probably is |
| 214 | caused by an erroneous print call-back routine. If we would |
| 215 | try to print all objects, we would enter an infinite loop. */ |
| 216 | static SCM |
| 217 | display_error_handler (struct display_error_handler_data *data, |
| 218 | SCM tag, SCM args) |
| 219 | { |
| 220 | SCM print_state = scm_make_print_state (); |
| 221 | scm_puts ("\nException during displaying of ", data->port); |
| 222 | scm_puts (data->mode, data->port); |
| 223 | scm_puts (": ", data->port); |
| 224 | scm_iprin1 (tag, data->port, SCM_PRINT_STATE (print_state)); |
| 225 | scm_putc ('\n', data->port); |
| 226 | return SCM_UNSPECIFIED; |
| 227 | } |
| 228 | |
| 229 | |
| 230 | /* The function scm_i_display_error prints out a detailed error message. This |
| 231 | * function will be called directly within libguile to signal error messages. |
| 232 | * No parameter checks will be performed by scm_i_display_error. Thus, User |
| 233 | * code should rather use the function scm_display_error. |
| 234 | */ |
| 235 | void |
| 236 | scm_i_display_error (SCM stack, SCM port, SCM subr, SCM message, SCM args, SCM rest) |
| 237 | { |
| 238 | struct display_error_args a; |
| 239 | struct display_error_handler_data data; |
| 240 | a.stack = stack; |
| 241 | a.port = port; |
| 242 | a.subr = subr; |
| 243 | a.message = message; |
| 244 | a.args = args; |
| 245 | a.rest = rest; |
| 246 | data.mode = "error"; |
| 247 | data.port = port; |
| 248 | scm_internal_catch (SCM_BOOL_T, |
| 249 | (scm_catch_body_t) display_error_body, &a, |
| 250 | (scm_catch_handler_t) display_error_handler, &data); |
| 251 | } |
| 252 | |
| 253 | |
| 254 | SCM_DEFINE (scm_display_error, "display-error", 6, 0, 0, |
| 255 | (SCM stack, SCM port, SCM subr, SCM message, SCM args, SCM rest), |
| 256 | "Display an error message to the output port @var{port}.\n" |
| 257 | "@var{stack} is the saved stack for the error, @var{subr} is\n" |
| 258 | "the name of the procedure in which the error occured and\n" |
| 259 | "@var{message} is the actual error message, which may contain\n" |
| 260 | "formatting instructions. These will format the arguments in\n" |
| 261 | "the list @var{args} accordingly. @var{rest} is currently\n" |
| 262 | "ignored.") |
| 263 | #define FUNC_NAME s_scm_display_error |
| 264 | { |
| 265 | SCM_VALIDATE_OUTPUT_PORT (2, port); |
| 266 | |
| 267 | scm_i_display_error (stack, port, subr, message, args, rest); |
| 268 | |
| 269 | return SCM_UNSPECIFIED; |
| 270 | } |
| 271 | #undef FUNC_NAME |
| 272 | |
| 273 | |
| 274 | typedef struct { |
| 275 | int level; |
| 276 | int length; |
| 277 | } print_params_t; |
| 278 | |
| 279 | static int n_print_params = 9; |
| 280 | static print_params_t default_print_params[] = { |
| 281 | { 4, 9 }, { 4, 3 }, |
| 282 | { 3, 4 }, { 3, 3 }, |
| 283 | { 2, 4 }, { 2, 3 }, |
| 284 | { 1, 4 }, { 1, 3 }, { 1, 2 } |
| 285 | }; |
| 286 | static print_params_t *print_params = default_print_params; |
| 287 | |
| 288 | #ifdef GUILE_DEBUG |
| 289 | SCM_DEFINE (scm_set_print_params_x, "set-print-params!", 1, 0, 0, |
| 290 | (SCM params), |
| 291 | "Set the print parameters to the values from @var{params}.\n" |
| 292 | "@var{params} must be a list of two-element lists which must\n" |
| 293 | "hold two integer values.") |
| 294 | #define FUNC_NAME s_scm_set_print_params_x |
| 295 | { |
| 296 | int i; |
| 297 | int n; |
| 298 | SCM ls; |
| 299 | print_params_t *new_params; |
| 300 | |
| 301 | SCM_VALIDATE_NONEMPTYLIST_COPYLEN (2, params, n); |
| 302 | for (ls = params; SCM_NNULLP (ls); ls = SCM_CDR (ls)) |
| 303 | SCM_ASSERT (scm_ilength (SCM_CAR (params)) == 2 |
| 304 | && SCM_INUMP (SCM_CAAR (ls)) |
| 305 | && SCM_INUM (SCM_CAAR (ls)) >= 0 |
| 306 | && SCM_INUMP (SCM_CADAR (ls)) |
| 307 | && SCM_INUM (SCM_CADAR (ls)) >= 0, |
| 308 | params, |
| 309 | SCM_ARG2, |
| 310 | s_scm_set_print_params_x); |
| 311 | new_params = scm_must_malloc (n * sizeof (print_params_t), |
| 312 | FUNC_NAME); |
| 313 | if (print_params != default_print_params) |
| 314 | scm_must_free (print_params); |
| 315 | print_params = new_params; |
| 316 | for (i = 0; i < n; ++i) |
| 317 | { |
| 318 | print_params[i].level = SCM_INUM (SCM_CAAR (params)); |
| 319 | print_params[i].length = SCM_INUM (SCM_CADAR (params)); |
| 320 | params = SCM_CDR (params); |
| 321 | } |
| 322 | n_print_params = n; |
| 323 | return SCM_UNSPECIFIED; |
| 324 | } |
| 325 | #undef FUNC_NAME |
| 326 | #endif |
| 327 | |
| 328 | static void |
| 329 | indent (int n, SCM port) |
| 330 | { |
| 331 | int i; |
| 332 | for (i = 0; i < n; ++i) |
| 333 | scm_putc (' ', port); |
| 334 | } |
| 335 | |
| 336 | static void |
| 337 | display_frame_expr (char *hdr,SCM exp,char *tlr,int indentation,SCM sport,SCM port,scm_print_state *pstate) |
| 338 | { |
| 339 | SCM string; |
| 340 | int i = 0, n; |
| 341 | scm_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (sport); |
| 342 | do |
| 343 | { |
| 344 | pstate->length = print_params[i].length; |
| 345 | ptob->seek (sport, 0, SEEK_SET); |
| 346 | if (SCM_CONSP (exp)) |
| 347 | { |
| 348 | pstate->level = print_params[i].level - 1; |
| 349 | scm_iprlist (hdr, exp, tlr[0], sport, pstate); |
| 350 | scm_puts (&tlr[1], sport); |
| 351 | } |
| 352 | else |
| 353 | { |
| 354 | pstate->level = print_params[i].level; |
| 355 | scm_iprin1 (exp, sport, pstate); |
| 356 | } |
| 357 | ptob->flush (sport); |
| 358 | n = ptob->seek (sport, 0, SEEK_CUR); |
| 359 | ++i; |
| 360 | } |
| 361 | while (indentation + n > SCM_BACKTRACE_WIDTH && i < n_print_params); |
| 362 | ptob->truncate (sport, n); |
| 363 | string = scm_strport_to_string (sport); |
| 364 | /* Remove control characters */ |
| 365 | for (i = 0; i < n; ++i) |
| 366 | if (iscntrl (SCM_STRING_CHARS (string)[i])) |
| 367 | SCM_STRING_CHARS (string)[i] = ' '; |
| 368 | /* Truncate */ |
| 369 | if (indentation + n > SCM_BACKTRACE_WIDTH) |
| 370 | { |
| 371 | n = SCM_BACKTRACE_WIDTH - indentation; |
| 372 | SCM_STRING_CHARS (string)[n - 1] = '$'; |
| 373 | } |
| 374 | |
| 375 | scm_lfwrite (SCM_STRING_CHARS (string), n, port); |
| 376 | } |
| 377 | |
| 378 | static void |
| 379 | display_application (SCM frame,int indentation,SCM sport,SCM port,scm_print_state *pstate) |
| 380 | { |
| 381 | SCM proc = SCM_FRAME_PROC (frame); |
| 382 | SCM name = (SCM_NFALSEP (scm_procedure_p (proc)) |
| 383 | ? scm_procedure_name (proc) |
| 384 | : SCM_BOOL_F); |
| 385 | display_frame_expr ("[", |
| 386 | scm_cons (SCM_NFALSEP (name) ? name : proc, |
| 387 | SCM_FRAME_ARGS (frame)), |
| 388 | SCM_FRAME_EVAL_ARGS_P (frame) ? " ..." : "]", |
| 389 | indentation, |
| 390 | sport, |
| 391 | port, |
| 392 | pstate); |
| 393 | } |
| 394 | |
| 395 | SCM_DEFINE (scm_display_application, "display-application", 1, 2, 0, |
| 396 | (SCM frame, SCM port, SCM indent), |
| 397 | "Display a procedure application @var{frame} to the output port\n" |
| 398 | "@var{port}. @var{indent} specifies the indentation of the\n" |
| 399 | "output.") |
| 400 | #define FUNC_NAME s_scm_display_application |
| 401 | { |
| 402 | SCM_VALIDATE_FRAME (1,frame); |
| 403 | if (SCM_UNBNDP (port)) |
| 404 | port = scm_cur_outp; |
| 405 | else |
| 406 | SCM_VALIDATE_OPOUTPORT (2,port); |
| 407 | if (SCM_UNBNDP (indent)) |
| 408 | indent = SCM_INUM0; |
| 409 | else |
| 410 | SCM_VALIDATE_INUM (3,indent); |
| 411 | |
| 412 | if (SCM_FRAME_PROC_P (frame)) |
| 413 | /* Display an application. */ |
| 414 | { |
| 415 | SCM sport, print_state; |
| 416 | scm_print_state *pstate; |
| 417 | |
| 418 | /* Create a string port used for adaptation of printing parameters. */ |
| 419 | sport = scm_mkstrport (SCM_INUM0, |
| 420 | scm_make_string (SCM_MAKINUM (240), |
| 421 | SCM_UNDEFINED), |
| 422 | SCM_OPN | SCM_WRTNG, |
| 423 | FUNC_NAME); |
| 424 | |
| 425 | /* Create a print state for printing of frames. */ |
| 426 | print_state = scm_make_print_state (); |
| 427 | pstate = SCM_PRINT_STATE (print_state); |
| 428 | pstate->writingp = 1; |
| 429 | pstate->fancyp = 1; |
| 430 | |
| 431 | display_application (frame, SCM_INUM (indent), sport, port, pstate); |
| 432 | return SCM_BOOL_T; |
| 433 | } |
| 434 | else |
| 435 | return SCM_BOOL_F; |
| 436 | } |
| 437 | #undef FUNC_NAME |
| 438 | |
| 439 | static void |
| 440 | display_frame (SCM frame,int nfield,int indentation,SCM sport,SCM port,scm_print_state *pstate) |
| 441 | { |
| 442 | int n, i, j; |
| 443 | |
| 444 | /* Announce missing frames? */ |
| 445 | if (!SCM_BACKWARDS_P && SCM_FRAME_OVERFLOW_P (frame)) |
| 446 | { |
| 447 | indent (nfield + 1 + indentation, port); |
| 448 | scm_puts ("...\n", port); |
| 449 | } |
| 450 | |
| 451 | /* Check size of frame number. */ |
| 452 | n = SCM_FRAME_NUMBER (frame); |
| 453 | for (i = 0, j = n; j > 0; ++i) j /= 10; |
| 454 | |
| 455 | /* Number indentation. */ |
| 456 | indent (nfield - (i ? i : 1), port); |
| 457 | |
| 458 | /* Frame number. */ |
| 459 | scm_iprin1 (SCM_MAKINUM (n), port, pstate); |
| 460 | |
| 461 | /* Real frame marker */ |
| 462 | scm_putc (SCM_FRAME_REAL_P (frame) ? '*' : ' ', port); |
| 463 | |
| 464 | /* Indentation. */ |
| 465 | indent (indentation, port); |
| 466 | |
| 467 | if (SCM_FRAME_PROC_P (frame)) |
| 468 | /* Display an application. */ |
| 469 | display_application (frame, nfield + 1 + indentation, sport, port, pstate); |
| 470 | else |
| 471 | /* Display a special form. */ |
| 472 | { |
| 473 | SCM source = SCM_FRAME_SOURCE (frame); |
| 474 | SCM copy = (SCM_CONSP (source) |
| 475 | ? scm_source_property (source, scm_sym_copy) |
| 476 | : SCM_BOOL_F); |
| 477 | SCM umcopy = (SCM_MEMOIZEDP (source) |
| 478 | ? scm_unmemoize (source) |
| 479 | : SCM_BOOL_F); |
| 480 | display_frame_expr ("(", |
| 481 | SCM_CONSP (copy) ? copy : umcopy, |
| 482 | ")", |
| 483 | nfield + 1 + indentation, |
| 484 | sport, |
| 485 | port, |
| 486 | pstate); |
| 487 | } |
| 488 | scm_putc ('\n', port); |
| 489 | |
| 490 | /* Announce missing frames? */ |
| 491 | if (SCM_BACKWARDS_P && SCM_FRAME_OVERFLOW_P (frame)) |
| 492 | { |
| 493 | indent (nfield + 1 + indentation, port); |
| 494 | scm_puts ("...\n", port); |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | struct display_backtrace_args { |
| 499 | SCM stack; |
| 500 | SCM port; |
| 501 | SCM first; |
| 502 | SCM depth; |
| 503 | }; |
| 504 | |
| 505 | static SCM |
| 506 | display_backtrace_body(struct display_backtrace_args *a) |
| 507 | #define FUNC_NAME "display_backtrace_body" |
| 508 | { |
| 509 | int n_frames, beg, end, n, i, j; |
| 510 | int nfield, indent_p, indentation; |
| 511 | SCM frame, sport, print_state; |
| 512 | scm_print_state *pstate; |
| 513 | |
| 514 | a->port = SCM_COERCE_OUTPORT (a->port); |
| 515 | |
| 516 | /* Argument checking and extraction. */ |
| 517 | SCM_ASSERT (SCM_STACKP (a->stack), |
| 518 | a->stack, |
| 519 | SCM_ARG1, |
| 520 | s_display_backtrace); |
| 521 | SCM_ASSERT (SCM_OPOUTPORTP (a->port), |
| 522 | a->port, |
| 523 | SCM_ARG2, |
| 524 | s_display_backtrace); |
| 525 | n_frames = SCM_INUM (scm_stack_length (a->stack)); |
| 526 | n = SCM_INUMP (a->depth) ? SCM_INUM (a->depth) : SCM_BACKTRACE_DEPTH; |
| 527 | if (SCM_BACKWARDS_P) |
| 528 | { |
| 529 | beg = SCM_INUMP (a->first) ? SCM_INUM (a->first) : 0; |
| 530 | end = beg + n - 1; |
| 531 | if (end >= n_frames) |
| 532 | end = n_frames - 1; |
| 533 | n = end - beg + 1; |
| 534 | } |
| 535 | else |
| 536 | { |
| 537 | if (SCM_INUMP (a->first)) |
| 538 | { |
| 539 | beg = SCM_INUM (a->first); |
| 540 | end = beg - n + 1; |
| 541 | if (end < 0) |
| 542 | end = 0; |
| 543 | } |
| 544 | else |
| 545 | { |
| 546 | beg = n - 1; |
| 547 | end = 0; |
| 548 | if (beg >= n_frames) |
| 549 | beg = n_frames - 1; |
| 550 | } |
| 551 | n = beg - end + 1; |
| 552 | } |
| 553 | SCM_ASSERT (beg >= 0 && beg < n_frames, a->first, SCM_ARG3, s_display_backtrace); |
| 554 | SCM_ASSERT (n > 0, a->depth, SCM_ARG4, s_display_backtrace); |
| 555 | |
| 556 | /* Create a string port used for adaptation of printing parameters. */ |
| 557 | sport = scm_mkstrport (SCM_INUM0, |
| 558 | scm_make_string (SCM_MAKINUM (240), SCM_UNDEFINED), |
| 559 | SCM_OPN | SCM_WRTNG, |
| 560 | FUNC_NAME); |
| 561 | |
| 562 | /* Create a print state for printing of frames. */ |
| 563 | print_state = scm_make_print_state (); |
| 564 | pstate = SCM_PRINT_STATE (print_state); |
| 565 | pstate->writingp = 1; |
| 566 | pstate->fancyp = 1; |
| 567 | |
| 568 | /* First find out if it's reasonable to do indentation. */ |
| 569 | if (SCM_BACKWARDS_P) |
| 570 | indent_p = 0; |
| 571 | else |
| 572 | { |
| 573 | indent_p = 1; |
| 574 | frame = scm_stack_ref (a->stack, SCM_MAKINUM (beg)); |
| 575 | for (i = 0, j = 0; i < n; ++i) |
| 576 | { |
| 577 | if (SCM_FRAME_REAL_P (frame)) |
| 578 | ++j; |
| 579 | if (j > SCM_BACKTRACE_INDENT) |
| 580 | { |
| 581 | indent_p = 0; |
| 582 | break; |
| 583 | } |
| 584 | frame = (SCM_BACKWARDS_P |
| 585 | ? SCM_FRAME_PREV (frame) |
| 586 | : SCM_FRAME_NEXT (frame)); |
| 587 | } |
| 588 | } |
| 589 | |
| 590 | /* Determine size of frame number field. */ |
| 591 | j = SCM_FRAME_NUMBER (scm_stack_ref (a->stack, SCM_MAKINUM (end))); |
| 592 | for (i = 0; j > 0; ++i) j /= 10; |
| 593 | nfield = i ? i : 1; |
| 594 | |
| 595 | /* Print frames. */ |
| 596 | frame = scm_stack_ref (a->stack, SCM_MAKINUM (beg)); |
| 597 | indentation = 1; |
| 598 | display_frame (frame, nfield, indentation, sport, a->port, pstate); |
| 599 | for (i = 1; i < n; ++i) |
| 600 | { |
| 601 | if (indent_p && SCM_FRAME_EVAL_ARGS_P (frame)) |
| 602 | ++indentation; |
| 603 | frame = SCM_BACKWARDS_P ? SCM_FRAME_PREV (frame) : SCM_FRAME_NEXT (frame); |
| 604 | display_frame (frame, nfield, indentation, sport, a->port, pstate); |
| 605 | } |
| 606 | |
| 607 | scm_remember_upto_here_1 (print_state); |
| 608 | |
| 609 | return SCM_UNSPECIFIED; |
| 610 | } |
| 611 | #undef FUNC_NAME |
| 612 | |
| 613 | SCM_DEFINE (scm_display_backtrace, "display-backtrace", 2, 2, 0, |
| 614 | (SCM stack, SCM port, SCM first, SCM depth), |
| 615 | "Display a backtrace to the output port @var{port}. @var{stack}\n" |
| 616 | "is the stack to take the backtrace from, @var{first} specifies\n" |
| 617 | "where in the stack to start and @var{depth} how much frames\n" |
| 618 | "to display. Both @var{first} and @var{depth} can be @code{#f},\n" |
| 619 | "which means that default values will be used.") |
| 620 | #define FUNC_NAME s_scm_display_backtrace |
| 621 | { |
| 622 | struct display_backtrace_args a; |
| 623 | struct display_error_handler_data data; |
| 624 | a.stack = stack; |
| 625 | a.port = port; |
| 626 | a.first = first; |
| 627 | a.depth = depth; |
| 628 | data.mode = "backtrace"; |
| 629 | data.port = port; |
| 630 | scm_internal_catch (SCM_BOOL_T, |
| 631 | (scm_catch_body_t) display_backtrace_body, &a, |
| 632 | (scm_catch_handler_t) display_error_handler, &data); |
| 633 | return SCM_UNSPECIFIED; |
| 634 | } |
| 635 | #undef FUNC_NAME |
| 636 | |
| 637 | SCM_VARIABLE (scm_has_shown_backtrace_hint_p_var, "has-shown-backtrace-hint?"); |
| 638 | |
| 639 | SCM_DEFINE (scm_backtrace, "backtrace", 0, 0, 0, |
| 640 | (), |
| 641 | "Display a backtrace of the stack saved by the last error\n" |
| 642 | "to the current output port.") |
| 643 | #define FUNC_NAME s_scm_backtrace |
| 644 | { |
| 645 | SCM the_last_stack = |
| 646 | scm_fluid_ref (SCM_VARIABLE_REF (scm_the_last_stack_fluid_var)); |
| 647 | if (SCM_NFALSEP (the_last_stack)) |
| 648 | { |
| 649 | scm_newline (scm_cur_outp); |
| 650 | scm_puts ("Backtrace:\n", scm_cur_outp); |
| 651 | scm_display_backtrace (the_last_stack, |
| 652 | scm_cur_outp, |
| 653 | SCM_UNDEFINED, |
| 654 | SCM_UNDEFINED); |
| 655 | scm_newline (scm_cur_outp); |
| 656 | if (SCM_FALSEP (SCM_VARIABLE_REF (scm_has_shown_backtrace_hint_p_var)) |
| 657 | && !SCM_BACKTRACE_P) |
| 658 | { |
| 659 | scm_puts ("Type \"(debug-enable 'backtrace)\" if you would like " |
| 660 | "a backtrace\n" |
| 661 | "automatically if an error occurs in the future.\n", |
| 662 | scm_cur_outp); |
| 663 | SCM_VARIABLE_SET (scm_has_shown_backtrace_hint_p_var, SCM_BOOL_T); |
| 664 | } |
| 665 | } |
| 666 | else |
| 667 | { |
| 668 | scm_puts ("No backtrace available.\n", scm_cur_outp); |
| 669 | } |
| 670 | return SCM_UNSPECIFIED; |
| 671 | } |
| 672 | #undef FUNC_NAME |
| 673 | |
| 674 | \f |
| 675 | |
| 676 | void |
| 677 | scm_init_backtrace () |
| 678 | { |
| 679 | SCM f = scm_make_fluid (); |
| 680 | scm_the_last_stack_fluid_var = scm_c_define ("the-last-stack", f); |
| 681 | |
| 682 | #ifndef SCM_MAGIC_SNARFER |
| 683 | #include "libguile/backtrace.x" |
| 684 | #endif |
| 685 | } |
| 686 | |
| 687 | /* |
| 688 | Local Variables: |
| 689 | c-file-style: "gnu" |
| 690 | End: |
| 691 | */ |