| 1 | /* Functions for deciding which macros are currently in scope. |
| 2 | Copyright 2002 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 2 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, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 20 | Boston, MA 02111-1307, USA. */ |
| 21 | |
| 22 | #include "defs.h" |
| 23 | |
| 24 | #include "macroscope.h" |
| 25 | #include "symtab.h" |
| 26 | #include "target.h" |
| 27 | #include "frame.h" |
| 28 | #include "inferior.h" |
| 29 | |
| 30 | |
| 31 | struct macro_scope * |
| 32 | sal_macro_scope (struct symtab_and_line sal) |
| 33 | { |
| 34 | struct macro_source_file *main; |
| 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 = macro_main (sal.symtab->macro_table); |
| 44 | ms->file = macro_lookup_inclusion (main, sal.symtab->filename); |
| 45 | |
| 46 | if (! ms->file) |
| 47 | internal_error |
| 48 | (__FILE__, __LINE__, |
| 49 | "\n" |
| 50 | "the symtab `%s' refers to a preprocessor macro table which doesn't\n" |
| 51 | "have any record of processing a file by that name.\n", |
| 52 | sal.symtab->filename); |
| 53 | |
| 54 | ms->line = sal.line; |
| 55 | |
| 56 | return ms; |
| 57 | } |
| 58 | |
| 59 | |
| 60 | struct macro_scope * |
| 61 | default_macro_scope (void) |
| 62 | { |
| 63 | struct symtab_and_line sal; |
| 64 | struct macro_source_file *main; |
| 65 | struct macro_scope *ms; |
| 66 | |
| 67 | /* If there's a selected frame, use its PC. */ |
| 68 | if (selected_frame) |
| 69 | sal = find_pc_line (selected_frame->pc, 0); |
| 70 | |
| 71 | /* If the target has any registers at all, then use its PC. Why we |
| 72 | would have registers but no stack, I'm not sure. */ |
| 73 | else if (target_has_registers) |
| 74 | sal = find_pc_line (read_pc (), 0); |
| 75 | |
| 76 | /* If all else fails, fall back to the current listing position. */ |
| 77 | else |
| 78 | { |
| 79 | /* Don't call select_source_symtab here. That can raise an |
| 80 | error if symbols aren't loaded, but GDB calls the expression |
| 81 | evaluator in all sorts of contexts. |
| 82 | |
| 83 | For example, commands like `set width' call the expression |
| 84 | evaluator to evaluate their numeric arguments. If the |
| 85 | current language is C, then that may call this function to |
| 86 | choose a scope for macro expansion. If you don't have any |
| 87 | symbol files loaded, then select_source_symtab will raise an |
| 88 | error. But `set width' shouldn't raise an error just because |
| 89 | it can't decide which scope to macro-expand its argument in. */ |
| 90 | sal.symtab = current_source_symtab; |
| 91 | sal.line = current_source_line; |
| 92 | } |
| 93 | |
| 94 | return sal_macro_scope (sal); |
| 95 | } |
| 96 | |
| 97 | |
| 98 | /* Look up the definition of the macro named NAME in scope at the source |
| 99 | location given by BATON, which must be a pointer to a `struct |
| 100 | macro_scope' structure. */ |
| 101 | struct macro_definition * |
| 102 | standard_macro_lookup (const char *name, void *baton) |
| 103 | { |
| 104 | struct macro_scope *ms = (struct macro_scope *) baton; |
| 105 | |
| 106 | return macro_lookup_definition (ms->file, ms->line, name); |
| 107 | } |