/* Printing of backtraces and error messages * Copyright (C) 1996,1997,1998,1999,2000,2001 Free Software Foundation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this software; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307 USA * * As a special exception, the Free Software Foundation gives permission * for additional uses of the text contained in its release of GUILE. * * The exception is that, if you link the GUILE library with other files * to produce an executable, this does not by itself cause the * resulting executable to be covered by the GNU General Public License. * Your use of that executable is in no way restricted on account of * linking the GUILE library code into it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. * * This exception applies only to the code released by the * Free Software Foundation under the name GUILE. If you copy * code from other Free Software Foundation releases into a copy of * GUILE, as the General Public License permits, the exception does * not apply to the code that you add in this way. To avoid misleading * anyone as to the status of such modified files, you must delete * this exception notice from them. * * If you write modifications of your own for GUILE, it is your choice * whether to permit this exception to apply to your modifications. * If you do not wish that, delete this exception notice. * * The author can be reached at djurfeldt@nada.kth.se * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */ #include #include #include "libguile/_scm.h" #ifdef HAVE_UNISTD_H #include #endif #ifdef HAVE_IO_H #include #endif #include "libguile/stacks.h" #include "libguile/srcprop.h" #include "libguile/struct.h" #include "libguile/strports.h" #include "libguile/throw.h" #include "libguile/fluids.h" #include "libguile/ports.h" #include "libguile/strings.h" #include "libguile/validate.h" #include "libguile/backtrace.h" #include "libguile/filesys.h" /* {Error reporting and backtraces} * (A first approximation.) * * Note that these functions shouldn't generate errors themselves. */ #ifndef SCM_RECKLESS #undef SCM_ASSERT #define SCM_ASSERT(_cond, _arg, _pos, _subr) \ if (!(_cond)) \ return SCM_BOOL_F; #endif SCM scm_the_last_stack_fluid_var; static void display_header (SCM source, SCM port) { if (SCM_MEMOIZEDP (source)) { SCM fname = scm_source_property (source, scm_sym_filename); SCM line = scm_source_property (source, scm_sym_line); SCM col = scm_source_property (source, scm_sym_column); /* Dirk:FIXME:: Maybe we should store the _port_ rather than the * filename with the source properties? Then we could in case of * non-file ports give at least some more details than just * "". */ if (SCM_STRINGP (fname)) scm_prin1 (fname, port, 0); else scm_puts ("", port); if (!SCM_FALSEP (line) && !SCM_FALSEP (col)) { scm_putc (':', port); scm_intprint (SCM_INUM (line) + 1, 10, port); scm_putc (':', port); scm_intprint (SCM_INUM (col) + 1, 10, port); } } else scm_puts ("ERROR", port); scm_puts (": ", port); } void scm_display_error_message (SCM message, SCM args, SCM port) { if (SCM_STRINGP (message) && !SCM_FALSEP (scm_list_p (args))) { scm_simple_format (port, message, args); scm_newline (port); } else { scm_display (message, port); scm_newline (port); } } static void display_expression (SCM frame,SCM pname,SCM source,SCM port) { SCM print_state = scm_make_print_state (); scm_print_state *pstate = SCM_PRINT_STATE (print_state); pstate->writingp = 0; pstate->fancyp = 1; pstate->level = 2; pstate->length = 3; if (SCM_SYMBOLP (pname) || SCM_STRINGP (pname)) { if (SCM_FRAMEP (frame) && SCM_FRAME_EVAL_ARGS_P (frame)) scm_puts ("While evaluating arguments to ", port); else scm_puts ("In procedure ", port); scm_iprin1 (pname, port, pstate); if (SCM_MEMOIZEDP (source)) { scm_puts (" in expression ", port); pstate->writingp = 1; scm_iprin1 (scm_unmemoize (source), port, pstate); } } else if (SCM_MEMOIZEDP (source)) { scm_puts ("In expression ", port); pstate->writingp = 1; scm_iprin1 (scm_unmemoize (source), port, pstate); } scm_puts (":\n", port); scm_free_print_state (print_state); } struct display_error_args { SCM stack; SCM port; SCM subr; SCM message; SCM args; SCM rest; }; static SCM display_error_body (struct display_error_args *a) { SCM current_frame = SCM_BOOL_F; SCM source = SCM_BOOL_F; SCM prev_frame = SCM_BOOL_F; SCM pname = a->subr; if (SCM_DEBUGGINGP && SCM_STACKP (a->stack) && SCM_STACK_LENGTH (a->stack) > 0) { current_frame = scm_stack_ref (a->stack, SCM_INUM0); source = SCM_FRAME_SOURCE (current_frame); prev_frame = SCM_FRAME_PREV (current_frame); if (!SCM_MEMOIZEDP (source) && !SCM_FALSEP (prev_frame)) source = SCM_FRAME_SOURCE (prev_frame); if (!SCM_SYMBOLP (pname) && !SCM_STRINGP (pname) && SCM_FRAME_PROC_P (current_frame) && SCM_EQ_P (scm_procedure_p (SCM_FRAME_PROC (current_frame)), SCM_BOOL_T)) pname = scm_procedure_name (SCM_FRAME_PROC (current_frame)); } if (SCM_SYMBOLP (pname) || SCM_STRINGP (pname) || SCM_MEMOIZEDP (source)) { display_header (source, a->port); display_expression (current_frame, pname, source, a->port); } display_header (source, a->port); scm_display_error_message (a->message, a->args, a->port); return SCM_UNSPECIFIED; } struct display_error_handler_data { char *mode; SCM port; }; /* This is the exception handler for error reporting routines. Note that it is very important that this handler *doesn't* try to print more than the error tag, since the error very probably is caused by an erroneous print call-back routine. If we would try to print all objects, we would enter an infinite loop. */ static SCM display_error_handler (struct display_error_handler_data *data, SCM tag, SCM args SCM_UNUSED) { SCM print_state = scm_make_print_state (); scm_puts ("\nException during displaying of ", data->port); scm_puts (data->mode, data->port); scm_puts (": ", data->port); scm_iprin1 (tag, data->port, SCM_PRINT_STATE (print_state)); scm_putc ('\n', data->port); return SCM_UNSPECIFIED; } /* The function scm_i_display_error prints out a detailed error message. This * function will be called directly within libguile to signal error messages. * No parameter checks will be performed by scm_i_display_error. Thus, User * code should rather use the function scm_display_error. */ void scm_i_display_error (SCM stack, SCM port, SCM subr, SCM message, SCM args, SCM rest) { struct display_error_args a; struct display_error_handler_data data; a.stack = stack; a.port = port; a.subr = subr; a.message = message; a.args = args; a.rest = rest; data.mode = "error"; data.port = port; scm_internal_catch (SCM_BOOL_T, (scm_t_catch_body) display_error_body, &a, (scm_t_catch_handler) display_error_handler, &data); } SCM_DEFINE (scm_display_error, "display-error", 6, 0, 0, (SCM stack, SCM port, SCM subr, SCM message, SCM args, SCM rest), "Display an error message to the output port @var{port}.\n" "@var{stack} is the saved stack for the error, @var{subr} is\n" "the name of the procedure in which the error occurred and\n" "@var{message} is the actual error message, which may contain\n" "formatting instructions. These will format the arguments in\n" "the list @var{args} accordingly. @var{rest} is currently\n" "ignored.") #define FUNC_NAME s_scm_display_error { SCM_VALIDATE_OUTPUT_PORT (2, port); scm_i_display_error (stack, port, subr, message, args, rest); return SCM_UNSPECIFIED; } #undef FUNC_NAME typedef struct { int level; int length; } print_params_t; static int n_print_params = 9; static print_params_t default_print_params[] = { { 4, 9 }, { 4, 3 }, { 3, 4 }, { 3, 3 }, { 2, 4 }, { 2, 3 }, { 1, 4 }, { 1, 3 }, { 1, 2 } }; static print_params_t *print_params = default_print_params; #ifdef GUILE_DEBUG SCM_DEFINE (scm_set_print_params_x, "set-print-params!", 1, 0, 0, (SCM params), "Set the print parameters to the values from @var{params}.\n" "@var{params} must be a list of two-element lists which must\n" "hold two integer values.") #define FUNC_NAME s_scm_set_print_params_x { int i; int n; SCM ls; print_params_t *new_params; SCM_VALIDATE_NONEMPTYLIST_COPYLEN (2, params, n); for (ls = params; !SCM_NULLP (ls); ls = SCM_CDR (ls)) SCM_ASSERT (scm_ilength (SCM_CAR (params)) == 2 && SCM_INUMP (SCM_CAAR (ls)) && SCM_INUM (SCM_CAAR (ls)) >= 0 && SCM_INUMP (SCM_CADAR (ls)) && SCM_INUM (SCM_CADAR (ls)) >= 0, params, SCM_ARG2, s_scm_set_print_params_x); new_params = scm_must_malloc (n * sizeof (print_params_t), FUNC_NAME); if (print_params != default_print_params) scm_must_free (print_params); print_params = new_params; for (i = 0; i < n; ++i) { print_params[i].level = SCM_INUM (SCM_CAAR (params)); print_params[i].length = SCM_INUM (SCM_CADAR (params)); params = SCM_CDR (params); } n_print_params = n; return SCM_UNSPECIFIED; } #undef FUNC_NAME #endif static void indent (int n, SCM port) { int i; for (i = 0; i < n; ++i) scm_putc (' ', port); } static void display_frame_expr (char *hdr,SCM exp,char *tlr,int indentation,SCM sport,SCM port,scm_print_state *pstate) { SCM string; int i = 0, n; scm_t_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (sport); do { pstate->length = print_params[i].length; ptob->seek (sport, 0, SEEK_SET); if (SCM_CONSP (exp)) { pstate->level = print_params[i].level - 1; scm_iprlist (hdr, exp, tlr[0], sport, pstate); scm_puts (&tlr[1], sport); } else { pstate->level = print_params[i].level; scm_iprin1 (exp, sport, pstate); } ptob->flush (sport); n = ptob->seek (sport, 0, SEEK_CUR); ++i; } while (indentation + n > SCM_BACKTRACE_WIDTH && i < n_print_params); ptob->truncate (sport, n); string = scm_strport_to_string (sport); /* Remove control characters */ for (i = 0; i < n; ++i) if (iscntrl (SCM_STRING_CHARS (string)[i])) SCM_STRING_CHARS (string)[i] = ' '; /* Truncate */ if (indentation + n > SCM_BACKTRACE_WIDTH) { n = SCM_BACKTRACE_WIDTH - indentation; SCM_STRING_CHARS (string)[n - 1] = '$'; } scm_lfwrite (SCM_STRING_CHARS (string), n, port); } static void display_application (SCM frame,int indentation,SCM sport,SCM port,scm_print_state *pstate) { SCM proc = SCM_FRAME_PROC (frame); SCM name = (!SCM_FALSEP (scm_procedure_p (proc)) ? scm_procedure_name (proc) : SCM_BOOL_F); display_frame_expr ("[", scm_cons (!SCM_FALSEP (name) ? name : proc, SCM_FRAME_ARGS (frame)), SCM_FRAME_EVAL_ARGS_P (frame) ? " ..." : "]", indentation, sport, port, pstate); } SCM_DEFINE (scm_display_application, "display-application", 1, 2, 0, (SCM frame, SCM port, SCM indent), "Display a procedure application @var{frame} to the output port\n" "@var{port}. @var{indent} specifies the indentation of the\n" "output.") #define FUNC_NAME s_scm_display_application { SCM_VALIDATE_FRAME (1,frame); if (SCM_UNBNDP (port)) port = scm_cur_outp; else SCM_VALIDATE_OPOUTPORT (2,port); if (SCM_UNBNDP (indent)) indent = SCM_INUM0; else SCM_VALIDATE_INUM (3,indent); if (SCM_FRAME_PROC_P (frame)) /* Display an application. */ { SCM sport, print_state; scm_print_state *pstate; /* Create a string port used for adaptation of printing parameters. */ sport = scm_mkstrport (SCM_INUM0, scm_make_string (SCM_MAKINUM (240), SCM_UNDEFINED), SCM_OPN | SCM_WRTNG, FUNC_NAME); /* Create a print state for printing of frames. */ print_state = scm_make_print_state (); pstate = SCM_PRINT_STATE (print_state); pstate->writingp = 1; pstate->fancyp = 1; display_application (frame, SCM_INUM (indent), sport, port, pstate); return SCM_BOOL_T; } else return SCM_BOOL_F; } #undef FUNC_NAME SCM_SYMBOL (sym_base, "base"); static void display_backtrace_get_file_line (SCM frame, SCM *file, SCM *line) { SCM source = SCM_FRAME_SOURCE (frame); *file = SCM_MEMOIZEDP (source) ? scm_source_property (source, scm_sym_filename) : SCM_BOOL_F; *line = (SCM_MEMOIZEDP (source)) ? scm_source_property (source, scm_sym_line) : SCM_BOOL_F; } static void display_backtrace_file (frame, last_file, port, pstate) SCM frame; SCM *last_file; SCM port; scm_print_state *pstate; { SCM file, line; display_backtrace_get_file_line (frame, &file, &line); if (file == *last_file) return; *last_file = file; scm_puts ("In ", port); if (SCM_FALSEP (file)) if (SCM_FALSEP (line)) scm_puts ("unknown file", port); else scm_puts ("current input", port); else { pstate->writingp = 0; scm_iprin1 (file, port, pstate); pstate->writingp = 1; } scm_puts (":\n", port); } static void display_backtrace_file_and_line (SCM frame, SCM port, scm_print_state *pstate) { SCM file, line; display_backtrace_get_file_line (frame, &file, &line); if (SCM_EQ_P (SCM_SHOW_FILE_NAME, sym_base)) { if (file == SCM_BOOL_F) { if (line == SCM_BOOL_F) scm_putc ('?', port); else scm_puts ("", port); } else { pstate -> writingp = 0; #ifdef HAVE_POSIX scm_iprin1 (SCM_STRINGP (file) ? scm_basename (file, SCM_UNDEFINED) : file, port, pstate); #else scm_iprin1 (file, port, pstate); #endif pstate -> writingp = 1; } scm_putc (':', port); } else if (line != SCM_BOOL_F) { int i, j=0; for (i = SCM_INUM (line)+1; i > 0; i = i/10, j++) ; indent (4-j, port); } if (line == SCM_BOOL_F) scm_puts (" ?", port); else scm_intprint (SCM_INUM (line) + 1, 10, port); scm_puts (": ", port); } static void display_frame (SCM frame,int nfield,int indentation,SCM sport,SCM port,scm_print_state *pstate) { int n, i, j; /* Announce missing frames? */ if (!SCM_BACKWARDS_P && SCM_FRAME_OVERFLOW_P (frame)) { indent (nfield + 1 + indentation, port); scm_puts ("...\n", port); } /* display file name and line number */ if (!SCM_FALSEP (SCM_SHOW_FILE_NAME)) display_backtrace_file_and_line (frame, port, pstate); /* Check size of frame number. */ n = SCM_FRAME_NUMBER (frame); for (i = 0, j = n; j > 0; ++i) j /= 10; /* Number indentation. */ indent (nfield - (i ? i : 1), port); /* Frame number. */ scm_iprin1 (SCM_MAKINUM (n), port, pstate); /* Real frame marker */ scm_putc (SCM_FRAME_REAL_P (frame) ? '*' : ' ', port); /* Indentation. */ indent (indentation, port); if (SCM_FRAME_PROC_P (frame)) /* Display an application. */ display_application (frame, nfield + 1 + indentation, sport, port, pstate); else /* Display a special form. */ { SCM source = SCM_FRAME_SOURCE (frame); SCM copy = (SCM_CONSP (source) ? scm_source_property (source, scm_sym_copy) : SCM_BOOL_F); SCM umcopy = (SCM_MEMOIZEDP (source) ? scm_unmemoize (source) : SCM_BOOL_F); display_frame_expr ("(", SCM_CONSP (copy) ? copy : umcopy, ")", nfield + 1 + indentation, sport, port, pstate); } scm_putc ('\n', port); /* Announce missing frames? */ if (SCM_BACKWARDS_P && SCM_FRAME_OVERFLOW_P (frame)) { indent (nfield + 1 + indentation, port); scm_puts ("...\n", port); } } struct display_backtrace_args { SCM stack; SCM port; SCM first; SCM depth; }; static SCM display_backtrace_body (struct display_backtrace_args *a) #define FUNC_NAME "display_backtrace_body" { int n_frames, beg, end, n, i, j; int nfield, indent_p, indentation; SCM frame, sport, print_state; SCM last_file; scm_print_state *pstate; a->port = SCM_COERCE_OUTPORT (a->port); /* Argument checking and extraction. */ SCM_VALIDATE_STACK (1, a->stack); SCM_VALIDATE_OPOUTPORT (2, a->port); n_frames = SCM_INUM (scm_stack_length (a->stack)); n = SCM_INUMP (a->depth) ? SCM_INUM (a->depth) : SCM_BACKTRACE_DEPTH; if (SCM_BACKWARDS_P) { beg = SCM_INUMP (a->first) ? SCM_INUM (a->first) : 0; end = beg + n - 1; if (end >= n_frames) end = n_frames - 1; n = end - beg + 1; } else { if (SCM_INUMP (a->first)) { beg = SCM_INUM (a->first); end = beg - n + 1; if (end < 0) end = 0; } else { beg = n - 1; end = 0; if (beg >= n_frames) beg = n_frames - 1; } n = beg - end + 1; } SCM_ASSERT (beg >= 0 && beg < n_frames, a->first, SCM_ARG3, s_display_backtrace); SCM_ASSERT (n > 0, a->depth, SCM_ARG4, s_display_backtrace); /* Create a string port used for adaptation of printing parameters. */ sport = scm_mkstrport (SCM_INUM0, scm_make_string (SCM_MAKINUM (240), SCM_UNDEFINED), SCM_OPN | SCM_WRTNG, FUNC_NAME); /* Create a print state for printing of frames. */ print_state = scm_make_print_state (); pstate = SCM_PRINT_STATE (print_state); pstate->writingp = 1; pstate->fancyp = 1; /* First find out if it's reasonable to do indentation. */ if (SCM_BACKWARDS_P) indent_p = 0; else { unsigned int j; indent_p = 1; frame = scm_stack_ref (a->stack, SCM_MAKINUM (beg)); for (i = 0, j = 0; i < n; ++i) { if (SCM_FRAME_REAL_P (frame)) ++j; if (j > SCM_BACKTRACE_INDENT) { indent_p = 0; break; } frame = (SCM_BACKWARDS_P ? SCM_FRAME_PREV (frame) : SCM_FRAME_NEXT (frame)); } } /* Determine size of frame number field. */ j = SCM_FRAME_NUMBER (scm_stack_ref (a->stack, SCM_MAKINUM (end))); for (i = 0; j > 0; ++i) j /= 10; nfield = i ? i : 1; /* Print frames. */ frame = scm_stack_ref (a->stack, SCM_MAKINUM (beg)); indentation = 1; last_file = SCM_UNDEFINED; for (i = 0; i < n; ++i) { if (!SCM_EQ_P (SCM_SHOW_FILE_NAME, sym_base)) display_backtrace_file (frame, &last_file, a->port, pstate); display_frame (frame, nfield, indentation, sport, a->port, pstate); if (indent_p && SCM_FRAME_EVAL_ARGS_P (frame)) ++indentation; frame = (SCM_BACKWARDS_P ? SCM_FRAME_PREV (frame) : SCM_FRAME_NEXT (frame)); } scm_remember_upto_here_1 (print_state); return SCM_UNSPECIFIED; } #undef FUNC_NAME SCM_DEFINE (scm_display_backtrace, "display-backtrace", 2, 2, 0, (SCM stack, SCM port, SCM first, SCM depth), "Display a backtrace to the output port @var{port}. @var{stack}\n" "is the stack to take the backtrace from, @var{first} specifies\n" "where in the stack to start and @var{depth} how much frames\n" "to display. Both @var{first} and @var{depth} can be @code{#f},\n" "which means that default values will be used.") #define FUNC_NAME s_scm_display_backtrace { struct display_backtrace_args a; struct display_error_handler_data data; a.stack = stack; a.port = port; a.first = first; a.depth = depth; data.mode = "backtrace"; data.port = port; scm_internal_catch (SCM_BOOL_T, (scm_t_catch_body) display_backtrace_body, &a, (scm_t_catch_handler) display_error_handler, &data); return SCM_UNSPECIFIED; } #undef FUNC_NAME SCM_VARIABLE (scm_has_shown_backtrace_hint_p_var, "has-shown-backtrace-hint?"); SCM_DEFINE (scm_backtrace, "backtrace", 0, 0, 0, (), "Display a backtrace of the stack saved by the last error\n" "to the current output port.") #define FUNC_NAME s_scm_backtrace { SCM the_last_stack = scm_fluid_ref (SCM_VARIABLE_REF (scm_the_last_stack_fluid_var)); if (!SCM_FALSEP (the_last_stack)) { scm_newline (scm_cur_outp); scm_puts ("Backtrace:\n", scm_cur_outp); scm_display_backtrace (the_last_stack, scm_cur_outp, SCM_UNDEFINED, SCM_UNDEFINED); scm_newline (scm_cur_outp); if (SCM_FALSEP (SCM_VARIABLE_REF (scm_has_shown_backtrace_hint_p_var)) && !SCM_BACKTRACE_P) { scm_puts ("Type \"(debug-enable 'backtrace)\" if you would like " "a backtrace\n" "automatically if an error occurs in the future.\n", scm_cur_outp); SCM_VARIABLE_SET (scm_has_shown_backtrace_hint_p_var, SCM_BOOL_T); } } else { scm_puts ("No backtrace available.\n", scm_cur_outp); } return SCM_UNSPECIFIED; } #undef FUNC_NAME void scm_init_backtrace () { SCM f = scm_make_fluid (); scm_the_last_stack_fluid_var = scm_c_define ("the-last-stack", f); #include "libguile/backtrace.x" } /* Local Variables: c-file-style: "gnu" End: */