| 1 | /* Functions for deciding which macros are currently in scope. |
| 2 | Copyright (C) 2002, 2007, 2008 Free Software Foundation, Inc. |
| 3 | Contributed by Red Hat, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | |
| 22 | #include "macroscope.h" |
| 23 | #include "symtab.h" |
| 24 | #include "source.h" |
| 25 | #include "target.h" |
| 26 | #include "frame.h" |
| 27 | #include "inferior.h" |
| 28 | #include "complaints.h" |
| 29 | |
| 30 | |
| 31 | struct macro_scope * |
| 32 | sal_macro_scope (struct symtab_and_line sal) |
| 33 | { |
| 34 | struct macro_source_file *main_file, *inclusion; |
| 35 | struct macro_scope *ms; |
| 36 | |
| 37 | if (! sal.symtab |
| 38 | || ! sal.symtab->macro_table) |
| 39 | return 0; |
| 40 | |
| 41 | ms = (struct macro_scope *) xmalloc (sizeof (*ms)); |
| 42 | |
| 43 | main_file = macro_main (sal.symtab->macro_table); |
| 44 | inclusion = macro_lookup_inclusion (main_file, sal.symtab->filename); |
| 45 | |
| 46 | if (inclusion) |
| 47 | { |
| 48 | ms->file = inclusion; |
| 49 | ms->line = sal.line; |
| 50 | } |
| 51 | else |
| 52 | { |
| 53 | /* There are, unfortunately, cases where a compilation unit can |
| 54 | have a symtab for a source file that doesn't appear in the |
| 55 | macro table. For example, at the moment, Dwarf doesn't have |
| 56 | any way in the .debug_macinfo section to describe the effect |
| 57 | of #line directives, so if you debug a YACC parser you'll get |
| 58 | a macro table which only mentions the .c files generated by |
| 59 | YACC, but symtabs that mention the .y files consumed by YACC. |
| 60 | |
| 61 | In the long run, we should extend the Dwarf macro info |
| 62 | representation to handle #line directives, and get GCC to |
| 63 | emit it. |
| 64 | |
| 65 | For the time being, though, we'll just treat these as |
| 66 | occurring at the end of the main source file. */ |
| 67 | ms->file = main_file; |
| 68 | ms->line = -1; |
| 69 | |
| 70 | complaint (&symfile_complaints, |
| 71 | _("symtab found for `%s', but that file\n" |
| 72 | "is not covered in the compilation unit's macro information"), |
| 73 | sal.symtab->filename); |
| 74 | } |
| 75 | |
| 76 | return ms; |
| 77 | } |
| 78 | |
| 79 | |
| 80 | struct macro_scope * |
| 81 | default_macro_scope (void) |
| 82 | { |
| 83 | struct symtab_and_line sal; |
| 84 | struct macro_scope *ms; |
| 85 | struct frame_info *frame; |
| 86 | |
| 87 | /* If there's a selected frame, use its PC. */ |
| 88 | frame = deprecated_safe_get_selected_frame (); |
| 89 | if (frame) |
| 90 | sal = find_pc_line (get_frame_pc (frame), 0); |
| 91 | |
| 92 | /* Fall back to the current listing position. */ |
| 93 | else |
| 94 | { |
| 95 | /* Don't call select_source_symtab here. That can raise an |
| 96 | error if symbols aren't loaded, but GDB calls the expression |
| 97 | evaluator in all sorts of contexts. |
| 98 | |
| 99 | For example, commands like `set width' call the expression |
| 100 | evaluator to evaluate their numeric arguments. If the |
| 101 | current language is C, then that may call this function to |
| 102 | choose a scope for macro expansion. If you don't have any |
| 103 | symbol files loaded, then get_current_or_default would raise an |
| 104 | error. But `set width' shouldn't raise an error just because |
| 105 | it can't decide which scope to macro-expand its argument in. */ |
| 106 | struct symtab_and_line cursal = |
| 107 | get_current_source_symtab_and_line (); |
| 108 | |
| 109 | sal.symtab = cursal.symtab; |
| 110 | sal.line = cursal.line; |
| 111 | } |
| 112 | |
| 113 | return sal_macro_scope (sal); |
| 114 | } |
| 115 | |
| 116 | |
| 117 | /* Look up the definition of the macro named NAME in scope at the source |
| 118 | location given by BATON, which must be a pointer to a `struct |
| 119 | macro_scope' structure. */ |
| 120 | struct macro_definition * |
| 121 | standard_macro_lookup (const char *name, void *baton) |
| 122 | { |
| 123 | struct macro_scope *ms = (struct macro_scope *) baton; |
| 124 | |
| 125 | return macro_lookup_definition (ms->file, ms->line, name); |
| 126 | } |