|  | /* C preprocessor macro tables for GDB. | 
|  | Copyright (C) 2002-2020 Free Software Foundation, Inc. | 
|  | Contributed by Red Hat, Inc. | 
|  |  | 
|  | This file is part of GDB. | 
|  |  | 
|  | 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 3 of the License, 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 program.  If not, see <http://www.gnu.org/licenses/>.  */ | 
|  |  | 
|  | #include "defs.h" | 
|  | #include "gdb_obstack.h" | 
|  | #include "splay-tree.h" | 
|  | #include "filenames.h" | 
|  | #include "symtab.h" | 
|  | #include "symfile.h" | 
|  | #include "objfiles.h" | 
|  | #include "macrotab.h" | 
|  | #include "bcache.h" | 
|  | #include "complaints.h" | 
|  | #include "macroexp.h" | 
|  |  | 
|  |  | 
|  | /* The macro table structure.  */ | 
|  |  | 
|  | struct macro_table | 
|  | { | 
|  | /* The obstack this table's data should be allocated in, or zero if | 
|  | we should use xmalloc.  */ | 
|  | struct obstack *obstack; | 
|  |  | 
|  | /* The bcache we should use to hold macro names, argument names, and | 
|  | definitions, or zero if we should use xmalloc.  */ | 
|  | gdb::bcache *bcache; | 
|  |  | 
|  | /* The main source file for this compilation unit --- the one whose | 
|  | name was given to the compiler.  This is the root of the | 
|  | #inclusion tree; everything else is #included from here.  */ | 
|  | struct macro_source_file *main_source; | 
|  |  | 
|  | /* Backlink to containing compilation unit, or NULL if there isn't one.  */ | 
|  | struct compunit_symtab *compunit_symtab; | 
|  |  | 
|  | /* True if macros in this table can be redefined without issuing an | 
|  | error.  */ | 
|  | int redef_ok; | 
|  |  | 
|  | /* The table of macro definitions.  This is a splay tree (an ordered | 
|  | binary tree that stays balanced, effectively), sorted by macro | 
|  | name.  Where a macro gets defined more than once (presumably with | 
|  | an #undefinition in between), we sort the definitions by the | 
|  | order they would appear in the preprocessor's output.  That is, | 
|  | if `a.c' #includes `m.h' and then #includes `n.h', and both | 
|  | header files #define X (with an #undef somewhere in between), | 
|  | then the definition from `m.h' appears in our splay tree before | 
|  | the one from `n.h'. | 
|  |  | 
|  | The splay tree's keys are `struct macro_key' pointers; | 
|  | the values are `struct macro_definition' pointers. | 
|  |  | 
|  | The splay tree, its nodes, and the keys and values are allocated | 
|  | in obstack, if it's non-zero, or with xmalloc otherwise.  The | 
|  | macro names, argument names, argument name arrays, and definition | 
|  | strings are all allocated in bcache, if non-zero, or with xmalloc | 
|  | otherwise.  */ | 
|  | splay_tree definitions; | 
|  | }; | 
|  |  | 
|  |  | 
|  |  | 
|  | /* Allocation and freeing functions.  */ | 
|  |  | 
|  | /* Allocate SIZE bytes of memory appropriately for the macro table T. | 
|  | This just checks whether T has an obstack, or whether its pieces | 
|  | should be allocated with xmalloc.  */ | 
|  | static void * | 
|  | macro_alloc (int size, struct macro_table *t) | 
|  | { | 
|  | if (t->obstack) | 
|  | return obstack_alloc (t->obstack, size); | 
|  | else | 
|  | return xmalloc (size); | 
|  | } | 
|  |  | 
|  |  | 
|  | static void | 
|  | macro_free (void *object, struct macro_table *t) | 
|  | { | 
|  | if (t->obstack) | 
|  | /* There are cases where we need to remove entries from a macro | 
|  | table, even when reading debugging information.  This should be | 
|  | rare, and there's no easy way to free arbitrary data from an | 
|  | obstack, so we just leak it.  */ | 
|  | ; | 
|  | else | 
|  | xfree (object); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* If the macro table T has a bcache, then cache the LEN bytes at ADDR | 
|  | there, and return the cached copy.  Otherwise, just xmalloc a copy | 
|  | of the bytes, and return a pointer to that.  */ | 
|  | static const void * | 
|  | macro_bcache (struct macro_table *t, const void *addr, int len) | 
|  | { | 
|  | if (t->bcache) | 
|  | return t->bcache->insert (addr, len); | 
|  | else | 
|  | { | 
|  | void *copy = xmalloc (len); | 
|  |  | 
|  | memcpy (copy, addr, len); | 
|  | return copy; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | /* If the macro table T has a bcache, cache the null-terminated string | 
|  | S there, and return a pointer to the cached copy.  Otherwise, | 
|  | xmalloc a copy and return that.  */ | 
|  | static const char * | 
|  | macro_bcache_str (struct macro_table *t, const char *s) | 
|  | { | 
|  | return (const char *) macro_bcache (t, s, strlen (s) + 1); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Free a possibly bcached object OBJ.  That is, if the macro table T | 
|  | has a bcache, do nothing; otherwise, xfree OBJ.  */ | 
|  | static void | 
|  | macro_bcache_free (struct macro_table *t, void *obj) | 
|  | { | 
|  | if (t->bcache) | 
|  | /* There are cases where we need to remove entries from a macro | 
|  | table, even when reading debugging information.  This should be | 
|  | rare, and there's no easy way to free data from a bcache, so we | 
|  | just leak it.  */ | 
|  | ; | 
|  | else | 
|  | xfree (obj); | 
|  | } | 
|  |  | 
|  |  | 
|  |  | 
|  | /* Macro tree keys, w/their comparison, allocation, and freeing functions.  */ | 
|  |  | 
|  | /* A key in the splay tree.  */ | 
|  | struct macro_key | 
|  | { | 
|  | /* The table we're in.  We only need this in order to free it, since | 
|  | the splay tree library's key and value freeing functions require | 
|  | that the key or value contain all the information needed to free | 
|  | themselves.  */ | 
|  | struct macro_table *table; | 
|  |  | 
|  | /* The name of the macro.  This is in the table's bcache, if it has | 
|  | one.  */ | 
|  | const char *name; | 
|  |  | 
|  | /* The source file and line number where the definition's scope | 
|  | begins.  This is also the line of the definition itself.  */ | 
|  | struct macro_source_file *start_file; | 
|  | int start_line; | 
|  |  | 
|  | /* The first source file and line after the definition's scope. | 
|  | (That is, the scope does not include this endpoint.)  If end_file | 
|  | is zero, then the definition extends to the end of the | 
|  | compilation unit.  */ | 
|  | struct macro_source_file *end_file; | 
|  | int end_line; | 
|  | }; | 
|  |  | 
|  |  | 
|  | /* Return the #inclusion depth of the source file FILE.  This is the | 
|  | number of #inclusions it took to reach this file.  For the main | 
|  | source file, the #inclusion depth is zero; for a file it #includes | 
|  | directly, the depth would be one; and so on.  */ | 
|  | static int | 
|  | inclusion_depth (struct macro_source_file *file) | 
|  | { | 
|  | int depth; | 
|  |  | 
|  | for (depth = 0; file->included_by; depth++) | 
|  | file = file->included_by; | 
|  |  | 
|  | return depth; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Compare two source locations (from the same compilation unit). | 
|  | This is part of the comparison function for the tree of | 
|  | definitions. | 
|  |  | 
|  | LINE1 and LINE2 are line numbers in the source files FILE1 and | 
|  | FILE2.  Return a value: | 
|  | - less than zero if {LINE,FILE}1 comes before {LINE,FILE}2, | 
|  | - greater than zero if {LINE,FILE}1 comes after {LINE,FILE}2, or | 
|  | - zero if they are equal. | 
|  |  | 
|  | When the two locations are in different source files --- perhaps | 
|  | one is in a header, while another is in the main source file --- we | 
|  | order them by where they would appear in the fully pre-processed | 
|  | sources, where all the #included files have been substituted into | 
|  | their places.  */ | 
|  | static int | 
|  | compare_locations (struct macro_source_file *file1, int line1, | 
|  | struct macro_source_file *file2, int line2) | 
|  | { | 
|  | /* We want to treat positions in an #included file as coming *after* | 
|  | the line containing the #include, but *before* the line after the | 
|  | include.  As we walk up the #inclusion tree toward the main | 
|  | source file, we update fileX and lineX as we go; includedX | 
|  | indicates whether the original position was from the #included | 
|  | file.  */ | 
|  | int included1 = 0; | 
|  | int included2 = 0; | 
|  |  | 
|  | /* If a file is zero, that means "end of compilation unit."  Handle | 
|  | that specially.  */ | 
|  | if (! file1) | 
|  | { | 
|  | if (! file2) | 
|  | return 0; | 
|  | else | 
|  | return 1; | 
|  | } | 
|  | else if (! file2) | 
|  | return -1; | 
|  |  | 
|  | /* If the two files are not the same, find their common ancestor in | 
|  | the #inclusion tree.  */ | 
|  | if (file1 != file2) | 
|  | { | 
|  | /* If one file is deeper than the other, walk up the #inclusion | 
|  | chain until the two files are at least at the same *depth*. | 
|  | Then, walk up both files in synchrony until they're the same | 
|  | file.  That file is the common ancestor.  */ | 
|  | int depth1 = inclusion_depth (file1); | 
|  | int depth2 = inclusion_depth (file2); | 
|  |  | 
|  | /* Only one of these while loops will ever execute in any given | 
|  | case.  */ | 
|  | while (depth1 > depth2) | 
|  | { | 
|  | line1 = file1->included_at_line; | 
|  | file1 = file1->included_by; | 
|  | included1 = 1; | 
|  | depth1--; | 
|  | } | 
|  | while (depth2 > depth1) | 
|  | { | 
|  | line2 = file2->included_at_line; | 
|  | file2 = file2->included_by; | 
|  | included2 = 1; | 
|  | depth2--; | 
|  | } | 
|  |  | 
|  | /* Now both file1 and file2 are at the same depth.  Walk toward | 
|  | the root of the tree until we find where the branches meet.  */ | 
|  | while (file1 != file2) | 
|  | { | 
|  | line1 = file1->included_at_line; | 
|  | file1 = file1->included_by; | 
|  | /* At this point, we know that the case the includedX flags | 
|  | are trying to deal with won't come up, but we'll just | 
|  | maintain them anyway.  */ | 
|  | included1 = 1; | 
|  |  | 
|  | line2 = file2->included_at_line; | 
|  | file2 = file2->included_by; | 
|  | included2 = 1; | 
|  |  | 
|  | /* Sanity check.  If file1 and file2 are really from the | 
|  | same compilation unit, then they should both be part of | 
|  | the same tree, and this shouldn't happen.  */ | 
|  | gdb_assert (file1 && file2); | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Now we've got two line numbers in the same file.  */ | 
|  | if (line1 == line2) | 
|  | { | 
|  | /* They can't both be from #included files.  Then we shouldn't | 
|  | have walked up this far.  */ | 
|  | gdb_assert (! included1 || ! included2); | 
|  |  | 
|  | /* Any #included position comes after a non-#included position | 
|  | with the same line number in the #including file.  */ | 
|  | if (included1) | 
|  | return 1; | 
|  | else if (included2) | 
|  | return -1; | 
|  | else | 
|  | return 0; | 
|  | } | 
|  | else | 
|  | return line1 - line2; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Compare a macro key KEY against NAME, the source file FILE, and | 
|  | line number LINE. | 
|  |  | 
|  | Sort definitions by name; for two definitions with the same name, | 
|  | place the one whose definition comes earlier before the one whose | 
|  | definition comes later. | 
|  |  | 
|  | Return -1, 0, or 1 if key comes before, is identical to, or comes | 
|  | after NAME, FILE, and LINE.  */ | 
|  | static int | 
|  | key_compare (struct macro_key *key, | 
|  | const char *name, struct macro_source_file *file, int line) | 
|  | { | 
|  | int names = strcmp (key->name, name); | 
|  |  | 
|  | if (names) | 
|  | return names; | 
|  |  | 
|  | return compare_locations (key->start_file, key->start_line, | 
|  | file, line); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* The macro tree comparison function, typed for the splay tree | 
|  | library's happiness.  */ | 
|  | static int | 
|  | macro_tree_compare (splay_tree_key untyped_key1, | 
|  | splay_tree_key untyped_key2) | 
|  | { | 
|  | struct macro_key *key1 = (struct macro_key *) untyped_key1; | 
|  | struct macro_key *key2 = (struct macro_key *) untyped_key2; | 
|  |  | 
|  | return key_compare (key1, key2->name, key2->start_file, key2->start_line); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Construct a new macro key node for a macro in table T whose name is | 
|  | NAME, and whose scope starts at LINE in FILE; register the name in | 
|  | the bcache.  */ | 
|  | static struct macro_key * | 
|  | new_macro_key (struct macro_table *t, | 
|  | const char *name, | 
|  | struct macro_source_file *file, | 
|  | int line) | 
|  | { | 
|  | struct macro_key *k = (struct macro_key *) macro_alloc (sizeof (*k), t); | 
|  |  | 
|  | memset (k, 0, sizeof (*k)); | 
|  | k->table = t; | 
|  | k->name = macro_bcache_str (t, name); | 
|  | k->start_file = file; | 
|  | k->start_line = line; | 
|  | k->end_file = 0; | 
|  |  | 
|  | return k; | 
|  | } | 
|  |  | 
|  |  | 
|  | static void | 
|  | macro_tree_delete_key (void *untyped_key) | 
|  | { | 
|  | struct macro_key *key = (struct macro_key *) untyped_key; | 
|  |  | 
|  | macro_bcache_free (key->table, (char *) key->name); | 
|  | macro_free (key, key->table); | 
|  | } | 
|  |  | 
|  |  | 
|  |  | 
|  | /* Building and querying the tree of #included files.  */ | 
|  |  | 
|  |  | 
|  | /* Allocate and initialize a new source file structure.  */ | 
|  | static struct macro_source_file * | 
|  | new_source_file (struct macro_table *t, | 
|  | const char *filename) | 
|  | { | 
|  | /* Get space for the source file structure itself.  */ | 
|  | struct macro_source_file *f | 
|  | = (struct macro_source_file *) macro_alloc (sizeof (*f), t); | 
|  |  | 
|  | memset (f, 0, sizeof (*f)); | 
|  | f->table = t; | 
|  | f->filename = macro_bcache_str (t, filename); | 
|  | f->includes = 0; | 
|  |  | 
|  | return f; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Free a source file, and all the source files it #included.  */ | 
|  | static void | 
|  | free_macro_source_file (struct macro_source_file *src) | 
|  | { | 
|  | struct macro_source_file *child, *next_child; | 
|  |  | 
|  | /* Free this file's children.  */ | 
|  | for (child = src->includes; child; child = next_child) | 
|  | { | 
|  | next_child = child->next_included; | 
|  | free_macro_source_file (child); | 
|  | } | 
|  |  | 
|  | macro_bcache_free (src->table, (char *) src->filename); | 
|  | macro_free (src, src->table); | 
|  | } | 
|  |  | 
|  |  | 
|  | struct macro_source_file * | 
|  | macro_set_main (struct macro_table *t, | 
|  | const char *filename) | 
|  | { | 
|  | /* You can't change a table's main source file.  What would that do | 
|  | to the tree?  */ | 
|  | gdb_assert (! t->main_source); | 
|  |  | 
|  | t->main_source = new_source_file (t, filename); | 
|  |  | 
|  | return t->main_source; | 
|  | } | 
|  |  | 
|  |  | 
|  | struct macro_source_file * | 
|  | macro_main (struct macro_table *t) | 
|  | { | 
|  | gdb_assert (t->main_source); | 
|  |  | 
|  | return t->main_source; | 
|  | } | 
|  |  | 
|  |  | 
|  | void | 
|  | macro_allow_redefinitions (struct macro_table *t) | 
|  | { | 
|  | gdb_assert (! t->obstack); | 
|  | t->redef_ok = 1; | 
|  | } | 
|  |  | 
|  |  | 
|  | struct macro_source_file * | 
|  | macro_include (struct macro_source_file *source, | 
|  | int line, | 
|  | const char *included) | 
|  | { | 
|  | struct macro_source_file *newobj; | 
|  | struct macro_source_file **link; | 
|  |  | 
|  | /* Find the right position in SOURCE's `includes' list for the new | 
|  | file.  Skip inclusions at earlier lines, until we find one at the | 
|  | same line or later --- or until the end of the list.  */ | 
|  | for (link = &source->includes; | 
|  | *link && (*link)->included_at_line < line; | 
|  | link = &(*link)->next_included) | 
|  | ; | 
|  |  | 
|  | /* Did we find another file already #included at the same line as | 
|  | the new one?  */ | 
|  | if (*link && line == (*link)->included_at_line) | 
|  | { | 
|  | /* This means the compiler is emitting bogus debug info.  (GCC | 
|  | circa March 2002 did this.)  It also means that the splay | 
|  | tree ordering function, macro_tree_compare, will abort, | 
|  | because it can't tell which #inclusion came first.  But GDB | 
|  | should tolerate bad debug info.  So: | 
|  |  | 
|  | First, squawk.  */ | 
|  |  | 
|  | std::string link_fullname = macro_source_fullname (*link); | 
|  | std::string source_fullname = macro_source_fullname (source); | 
|  | complaint (_("both `%s' and `%s' allegedly #included at %s:%d"), | 
|  | included, link_fullname.c_str (), source_fullname.c_str (), | 
|  | line); | 
|  |  | 
|  | /* Now, choose a new, unoccupied line number for this | 
|  | #inclusion, after the alleged #inclusion line.  */ | 
|  | while (*link && line == (*link)->included_at_line) | 
|  | { | 
|  | /* This line number is taken, so try the next line.  */ | 
|  | line++; | 
|  | link = &(*link)->next_included; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* At this point, we know that LINE is an unused line number, and | 
|  | *LINK points to the entry an #inclusion at that line should | 
|  | precede.  */ | 
|  | newobj = new_source_file (source->table, included); | 
|  | newobj->included_by = source; | 
|  | newobj->included_at_line = line; | 
|  | newobj->next_included = *link; | 
|  | *link = newobj; | 
|  |  | 
|  | return newobj; | 
|  | } | 
|  |  | 
|  |  | 
|  | struct macro_source_file * | 
|  | macro_lookup_inclusion (struct macro_source_file *source, const char *name) | 
|  | { | 
|  | /* Is SOURCE itself named NAME?  */ | 
|  | if (filename_cmp (name, source->filename) == 0) | 
|  | return source; | 
|  |  | 
|  | /* It's not us.  Try all our children, and return the lowest.  */ | 
|  | { | 
|  | struct macro_source_file *child; | 
|  | struct macro_source_file *best = NULL; | 
|  | int best_depth = 0; | 
|  |  | 
|  | for (child = source->includes; child; child = child->next_included) | 
|  | { | 
|  | struct macro_source_file *result | 
|  | = macro_lookup_inclusion (child, name); | 
|  |  | 
|  | if (result) | 
|  | { | 
|  | int result_depth = inclusion_depth (result); | 
|  |  | 
|  | if (! best || result_depth < best_depth) | 
|  | { | 
|  | best = result; | 
|  | best_depth = result_depth; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | return best; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  |  | 
|  | /* Registering and looking up macro definitions.  */ | 
|  |  | 
|  |  | 
|  | /* Construct a definition for a macro in table T.  Cache all strings, | 
|  | and the macro_definition structure itself, in T's bcache.  */ | 
|  | static struct macro_definition * | 
|  | new_macro_definition (struct macro_table *t, | 
|  | enum macro_kind kind, | 
|  | int argc, const char **argv, | 
|  | const char *replacement) | 
|  | { | 
|  | struct macro_definition *d | 
|  | = (struct macro_definition *) macro_alloc (sizeof (*d), t); | 
|  |  | 
|  | memset (d, 0, sizeof (*d)); | 
|  | d->table = t; | 
|  | d->kind = kind; | 
|  | d->replacement = macro_bcache_str (t, replacement); | 
|  | d->argc = argc; | 
|  |  | 
|  | if (kind == macro_function_like) | 
|  | { | 
|  | int i; | 
|  | const char **cached_argv; | 
|  | int cached_argv_size = argc * sizeof (*cached_argv); | 
|  |  | 
|  | /* Bcache all the arguments.  */ | 
|  | cached_argv = (const char **) alloca (cached_argv_size); | 
|  | for (i = 0; i < argc; i++) | 
|  | cached_argv[i] = macro_bcache_str (t, argv[i]); | 
|  |  | 
|  | /* Now bcache the array of argument pointers itself.  */ | 
|  | d->argv = ((const char * const *) | 
|  | macro_bcache (t, cached_argv, cached_argv_size)); | 
|  | } | 
|  |  | 
|  | /* We don't bcache the entire definition structure because it's got | 
|  | a pointer to the macro table in it; since each compilation unit | 
|  | has its own macro table, you'd only get bcache hits for identical | 
|  | definitions within a compilation unit, which seems unlikely. | 
|  |  | 
|  | "So, why do macro definitions have pointers to their macro tables | 
|  | at all?"  Well, when the splay tree library wants to free a | 
|  | node's value, it calls the value freeing function with nothing | 
|  | but the value itself.  It makes the (apparently reasonable) | 
|  | assumption that the value carries enough information to free | 
|  | itself.  But not all macro tables have bcaches, so not all macro | 
|  | definitions would be bcached.  There's no way to tell whether a | 
|  | given definition is bcached without knowing which table the | 
|  | definition belongs to.  ...  blah.  The thing's only sixteen | 
|  | bytes anyway, and we can still bcache the name, args, and | 
|  | definition, so we just don't bother bcaching the definition | 
|  | structure itself.  */ | 
|  | return d; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Free a macro definition.  */ | 
|  | static void | 
|  | macro_tree_delete_value (void *untyped_definition) | 
|  | { | 
|  | struct macro_definition *d = (struct macro_definition *) untyped_definition; | 
|  | struct macro_table *t = d->table; | 
|  |  | 
|  | if (d->kind == macro_function_like) | 
|  | { | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < d->argc; i++) | 
|  | macro_bcache_free (t, (char *) d->argv[i]); | 
|  | macro_bcache_free (t, (char **) d->argv); | 
|  | } | 
|  |  | 
|  | macro_bcache_free (t, (char *) d->replacement); | 
|  | macro_free (d, t); | 
|  | } | 
|  |  | 
|  |  | 
|  | /* Find the splay tree node for the definition of NAME at LINE in | 
|  | SOURCE, or zero if there is none.  */ | 
|  | static splay_tree_node | 
|  | find_definition (const char *name, | 
|  | struct macro_source_file *file, | 
|  | int line) | 
|  | { | 
|  | struct macro_table *t = file->table; | 
|  | splay_tree_node n; | 
|  |  | 
|  | /* Construct a macro_key object, just for the query.  */ | 
|  | struct macro_key query; | 
|  |  | 
|  | query.name = name; | 
|  | query.start_file = file; | 
|  | query.start_line = line; | 
|  | query.end_file = NULL; | 
|  |  | 
|  | n = splay_tree_lookup (t->definitions, (splay_tree_key) &query); | 
|  | if (! n) | 
|  | { | 
|  | /* It's okay for us to do two queries like this: the real work | 
|  | of the searching is done when we splay, and splaying the tree | 
|  | a second time at the same key is a constant time operation. | 
|  | If this still bugs you, you could always just extend the | 
|  | splay tree library with a predecessor-or-equal operation, and | 
|  | use that.  */ | 
|  | splay_tree_node pred = splay_tree_predecessor (t->definitions, | 
|  | (splay_tree_key) &query); | 
|  |  | 
|  | if (pred) | 
|  | { | 
|  | /* Make sure this predecessor actually has the right name. | 
|  | We just want to search within a given name's definitions.  */ | 
|  | struct macro_key *found = (struct macro_key *) pred->key; | 
|  |  | 
|  | if (strcmp (found->name, name) == 0) | 
|  | n = pred; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (n) | 
|  | { | 
|  | struct macro_key *found = (struct macro_key *) n->key; | 
|  |  | 
|  | /* Okay, so this definition has the right name, and its scope | 
|  | begins before the given source location.  But does its scope | 
|  | end after the given source location?  */ | 
|  | if (compare_locations (file, line, found->end_file, found->end_line) < 0) | 
|  | return n; | 
|  | else | 
|  | return 0; | 
|  | } | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* If NAME already has a definition in scope at LINE in SOURCE, return | 
|  | the key.  If the old definition is different from the definition | 
|  | given by KIND, ARGC, ARGV, and REPLACEMENT, complain, too. | 
|  | Otherwise, return zero.  (ARGC and ARGV are meaningless unless KIND | 
|  | is `macro_function_like'.)  */ | 
|  | static struct macro_key * | 
|  | check_for_redefinition (struct macro_source_file *source, int line, | 
|  | const char *name, enum macro_kind kind, | 
|  | int argc, const char **argv, | 
|  | const char *replacement) | 
|  | { | 
|  | splay_tree_node n = find_definition (name, source, line); | 
|  |  | 
|  | if (n) | 
|  | { | 
|  | struct macro_key *found_key = (struct macro_key *) n->key; | 
|  | struct macro_definition *found_def | 
|  | = (struct macro_definition *) n->value; | 
|  | int same = 1; | 
|  |  | 
|  | /* Is this definition the same as the existing one? | 
|  | According to the standard, this comparison needs to be done | 
|  | on lists of tokens, not byte-by-byte, as we do here.  But | 
|  | that's too hard for us at the moment, and comparing | 
|  | byte-by-byte will only yield false negatives (i.e., extra | 
|  | warning messages), not false positives (i.e., unnoticed | 
|  | definition changes).  */ | 
|  | if (kind != found_def->kind) | 
|  | same = 0; | 
|  | else if (strcmp (replacement, found_def->replacement)) | 
|  | same = 0; | 
|  | else if (kind == macro_function_like) | 
|  | { | 
|  | if (argc != found_def->argc) | 
|  | same = 0; | 
|  | else | 
|  | { | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < argc; i++) | 
|  | if (strcmp (argv[i], found_def->argv[i])) | 
|  | same = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (! same) | 
|  | { | 
|  | std::string source_fullname = macro_source_fullname (source); | 
|  | std::string found_key_fullname | 
|  | = macro_source_fullname (found_key->start_file); | 
|  | complaint (_("macro `%s' redefined at %s:%d; " | 
|  | "original definition at %s:%d"), | 
|  | name, source_fullname.c_str (), line, | 
|  | found_key_fullname.c_str (), | 
|  | found_key->start_line); | 
|  | } | 
|  |  | 
|  | return found_key; | 
|  | } | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* A helper function to define a new object-like or function-like macro | 
|  | according to KIND.  When KIND is macro_object_like, | 
|  | the macro_special_kind must be provided as ARGC, and ARGV must be NULL. | 
|  | When KIND is macro_function_like, ARGC and ARGV are giving the function | 
|  | arguments.  */ | 
|  |  | 
|  | static void | 
|  | macro_define_internal (struct macro_source_file *source, int line, | 
|  | const char *name, enum macro_kind kind, | 
|  | int argc, const char **argv, | 
|  | const char *replacement) | 
|  | { | 
|  | struct macro_table *t = source->table; | 
|  | struct macro_key *k = NULL; | 
|  | struct macro_definition *d; | 
|  |  | 
|  | if (! t->redef_ok) | 
|  | k = check_for_redefinition (source, line, | 
|  | name, kind, | 
|  | argc, argv, | 
|  | replacement); | 
|  |  | 
|  | /* If we're redefining a symbol, and the existing key would be | 
|  | identical to our new key, then the splay_tree_insert function | 
|  | will try to delete the old definition.  When the definition is | 
|  | living on an obstack, this isn't a happy thing. | 
|  |  | 
|  | Since this only happens in the presence of questionable debug | 
|  | info, we just ignore all definitions after the first.  The only | 
|  | case I know of where this arises is in GCC's output for | 
|  | predefined macros, and all the definitions are the same in that | 
|  | case.  */ | 
|  | if (k && ! key_compare (k, name, source, line)) | 
|  | return; | 
|  |  | 
|  | k = new_macro_key (t, name, source, line); | 
|  | d = new_macro_definition (t, kind, argc, argv, replacement); | 
|  | splay_tree_insert (t->definitions, (splay_tree_key) k, (splay_tree_value) d); | 
|  | } | 
|  |  | 
|  | /* A helper function to define a new object-like macro.  */ | 
|  |  | 
|  | static void | 
|  | macro_define_object_internal (struct macro_source_file *source, int line, | 
|  | const char *name, const char *replacement, | 
|  | enum macro_special_kind special_kind) | 
|  | { | 
|  | macro_define_internal (source, line, | 
|  | name, macro_object_like, | 
|  | special_kind, NULL, | 
|  | replacement); | 
|  | } | 
|  |  | 
|  | void | 
|  | macro_define_object (struct macro_source_file *source, int line, | 
|  | const char *name, const char *replacement) | 
|  | { | 
|  | macro_define_object_internal (source, line, name, replacement, | 
|  | macro_ordinary); | 
|  | } | 
|  |  | 
|  | /* See macrotab.h.  */ | 
|  |  | 
|  | void | 
|  | macro_define_special (struct macro_table *table) | 
|  | { | 
|  | macro_define_object_internal (table->main_source, -1, "__FILE__", "", | 
|  | macro_FILE); | 
|  | macro_define_object_internal (table->main_source, -1, "__LINE__", "", | 
|  | macro_LINE); | 
|  | } | 
|  |  | 
|  | void | 
|  | macro_define_function (struct macro_source_file *source, int line, | 
|  | const char *name, int argc, const char **argv, | 
|  | const char *replacement) | 
|  | { | 
|  | macro_define_internal (source, line, | 
|  | name, macro_function_like, | 
|  | argc, argv, | 
|  | replacement); | 
|  | } | 
|  |  | 
|  | void | 
|  | macro_undef (struct macro_source_file *source, int line, | 
|  | const char *name) | 
|  | { | 
|  | splay_tree_node n = find_definition (name, source, line); | 
|  |  | 
|  | if (n) | 
|  | { | 
|  | struct macro_key *key = (struct macro_key *) n->key; | 
|  |  | 
|  | /* If we're removing a definition at exactly the same point that | 
|  | we defined it, then just delete the entry altogether.  GCC | 
|  | 4.1.2 will generate DWARF that says to do this if you pass it | 
|  | arguments like '-DFOO -UFOO -DFOO=2'.  */ | 
|  | if (source == key->start_file | 
|  | && line == key->start_line) | 
|  | splay_tree_remove (source->table->definitions, n->key); | 
|  |  | 
|  | else | 
|  | { | 
|  | /* This function is the only place a macro's end-of-scope | 
|  | location gets set to anything other than "end of the | 
|  | compilation unit" (i.e., end_file is zero).  So if this | 
|  | macro already has its end-of-scope set, then we're | 
|  | probably seeing a second #undefinition for the same | 
|  | #definition.  */ | 
|  | if (key->end_file) | 
|  | { | 
|  | std::string source_fullname = macro_source_fullname (source); | 
|  | std::string key_fullname = macro_source_fullname (key->end_file); | 
|  | complaint (_("macro '%s' is #undefined twice," | 
|  | " at %s:%d and %s:%d"), | 
|  | name, source_fullname.c_str (), line, | 
|  | key_fullname.c_str (), | 
|  | key->end_line); | 
|  | } | 
|  |  | 
|  | /* Whether or not we've seen a prior #undefinition, wipe out | 
|  | the old ending point, and make this the ending point.  */ | 
|  | key->end_file = source; | 
|  | key->end_line = line; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | /* According to the ISO C standard, an #undef for a symbol that | 
|  | has no macro definition in scope is ignored.  So we should | 
|  | ignore it too.  */ | 
|  | #if 0 | 
|  | complaint (_("no definition for macro `%s' in scope to #undef at %s:%d"), | 
|  | name, source->filename, line); | 
|  | #endif | 
|  | } | 
|  | } | 
|  |  | 
|  | /* A helper function that rewrites the definition of a special macro, | 
|  | when needed.  */ | 
|  |  | 
|  | static struct macro_definition * | 
|  | fixup_definition (const char *filename, int line, struct macro_definition *def) | 
|  | { | 
|  | static char *saved_expansion; | 
|  |  | 
|  | if (saved_expansion) | 
|  | { | 
|  | xfree (saved_expansion); | 
|  | saved_expansion = NULL; | 
|  | } | 
|  |  | 
|  | if (def->kind == macro_object_like) | 
|  | { | 
|  | if (def->argc == macro_FILE) | 
|  | { | 
|  | saved_expansion = macro_stringify (filename); | 
|  | def->replacement = saved_expansion; | 
|  | } | 
|  | else if (def->argc == macro_LINE) | 
|  | { | 
|  | saved_expansion = xstrprintf ("%d", line); | 
|  | def->replacement = saved_expansion; | 
|  | } | 
|  | } | 
|  |  | 
|  | return def; | 
|  | } | 
|  |  | 
|  | struct macro_definition * | 
|  | macro_lookup_definition (struct macro_source_file *source, | 
|  | int line, const char *name) | 
|  | { | 
|  | splay_tree_node n = find_definition (name, source, line); | 
|  |  | 
|  | if (n) | 
|  | { | 
|  | std::string source_fullname = macro_source_fullname (source); | 
|  | return fixup_definition (source_fullname.c_str (), line, | 
|  | (struct macro_definition *) n->value); | 
|  | } | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  |  | 
|  | struct macro_source_file * | 
|  | macro_definition_location (struct macro_source_file *source, | 
|  | int line, | 
|  | const char *name, | 
|  | int *definition_line) | 
|  | { | 
|  | splay_tree_node n = find_definition (name, source, line); | 
|  |  | 
|  | if (n) | 
|  | { | 
|  | struct macro_key *key = (struct macro_key *) n->key; | 
|  |  | 
|  | *definition_line = key->start_line; | 
|  | return key->start_file; | 
|  | } | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* The type for callback data for iterating the splay tree in | 
|  | macro_for_each and macro_for_each_in_scope.  Only the latter uses | 
|  | the FILE and LINE fields.  */ | 
|  | struct macro_for_each_data | 
|  | { | 
|  | gdb::function_view<macro_callback_fn> fn; | 
|  | struct macro_source_file *file; | 
|  | int line; | 
|  | }; | 
|  |  | 
|  | /* Helper function for macro_for_each.  */ | 
|  | static int | 
|  | foreach_macro (splay_tree_node node, void *arg) | 
|  | { | 
|  | struct macro_for_each_data *datum = (struct macro_for_each_data *) arg; | 
|  | struct macro_key *key = (struct macro_key *) node->key; | 
|  | struct macro_definition *def; | 
|  |  | 
|  | std::string key_fullname = macro_source_fullname (key->start_file); | 
|  | def = fixup_definition (key_fullname.c_str (), key->start_line, | 
|  | (struct macro_definition *) node->value); | 
|  |  | 
|  | datum->fn (key->name, def, key->start_file, key->start_line); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Call FN for every macro in TABLE.  */ | 
|  | void | 
|  | macro_for_each (struct macro_table *table, | 
|  | gdb::function_view<macro_callback_fn> fn) | 
|  | { | 
|  | struct macro_for_each_data datum; | 
|  |  | 
|  | datum.fn = fn; | 
|  | datum.file = NULL; | 
|  | datum.line = 0; | 
|  | splay_tree_foreach (table->definitions, foreach_macro, &datum); | 
|  | } | 
|  |  | 
|  | static int | 
|  | foreach_macro_in_scope (splay_tree_node node, void *info) | 
|  | { | 
|  | struct macro_for_each_data *datum = (struct macro_for_each_data *) info; | 
|  | struct macro_key *key = (struct macro_key *) node->key; | 
|  | struct macro_definition *def; | 
|  |  | 
|  | std::string datum_fullname = macro_source_fullname (datum->file); | 
|  | def = fixup_definition (datum_fullname.c_str (), datum->line, | 
|  | (struct macro_definition *) node->value); | 
|  |  | 
|  | /* See if this macro is defined before the passed-in line, and | 
|  | extends past that line.  */ | 
|  | if (compare_locations (key->start_file, key->start_line, | 
|  | datum->file, datum->line) < 0 | 
|  | && (!key->end_file | 
|  | || compare_locations (key->end_file, key->end_line, | 
|  | datum->file, datum->line) >= 0)) | 
|  | datum->fn (key->name, def, key->start_file, key->start_line); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Call FN for every macro is visible in SCOPE.  */ | 
|  | void | 
|  | macro_for_each_in_scope (struct macro_source_file *file, int line, | 
|  | gdb::function_view<macro_callback_fn> fn) | 
|  | { | 
|  | struct macro_for_each_data datum; | 
|  |  | 
|  | datum.fn = fn; | 
|  | datum.file = file; | 
|  | datum.line = line; | 
|  | splay_tree_foreach (file->table->definitions, | 
|  | foreach_macro_in_scope, &datum); | 
|  | } | 
|  |  | 
|  |  | 
|  |  | 
|  | /* Creating and freeing macro tables.  */ | 
|  |  | 
|  |  | 
|  | struct macro_table * | 
|  | new_macro_table (struct obstack *obstack, gdb::bcache *b, | 
|  | struct compunit_symtab *cust) | 
|  | { | 
|  | struct macro_table *t; | 
|  |  | 
|  | /* First, get storage for the `struct macro_table' itself.  */ | 
|  | if (obstack) | 
|  | t = XOBNEW (obstack, struct macro_table); | 
|  | else | 
|  | t = XNEW (struct macro_table); | 
|  |  | 
|  | memset (t, 0, sizeof (*t)); | 
|  | t->obstack = obstack; | 
|  | t->bcache = b; | 
|  | t->main_source = NULL; | 
|  | t->compunit_symtab = cust; | 
|  | t->redef_ok = 0; | 
|  | t->definitions = (splay_tree_new_with_allocator | 
|  | (macro_tree_compare, | 
|  | ((splay_tree_delete_key_fn) macro_tree_delete_key), | 
|  | ((splay_tree_delete_value_fn) macro_tree_delete_value), | 
|  | ((splay_tree_allocate_fn) macro_alloc), | 
|  | ((splay_tree_deallocate_fn) macro_free), | 
|  | t)); | 
|  |  | 
|  | return t; | 
|  | } | 
|  |  | 
|  |  | 
|  | void | 
|  | free_macro_table (struct macro_table *table) | 
|  | { | 
|  | /* Free the source file tree.  */ | 
|  | free_macro_source_file (table->main_source); | 
|  |  | 
|  | /* Free the table of macro definitions.  */ | 
|  | splay_tree_delete (table->definitions); | 
|  | } | 
|  |  | 
|  | /* See macrotab.h for the comment.  */ | 
|  |  | 
|  | std::string | 
|  | macro_source_fullname (struct macro_source_file *file) | 
|  | { | 
|  | const char *comp_dir = NULL; | 
|  |  | 
|  | if (file->table->compunit_symtab != NULL) | 
|  | comp_dir = COMPUNIT_DIRNAME (file->table->compunit_symtab); | 
|  |  | 
|  | if (comp_dir == NULL || IS_ABSOLUTE_PATH (file->filename)) | 
|  | return file->filename; | 
|  |  | 
|  | return std::string (comp_dir) + SLASH_STRING + file->filename; | 
|  | } |