885 lines
28 KiB
C
885 lines
28 KiB
C
/* GDB routines for manipulating the minimal symbol tables.
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Copyright 1992, 1993, 1994, 1996, 1996 Free Software Foundation, Inc.
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Contributed by Cygnus Support, using pieces from other GDB modules.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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/* This file contains support routines for creating, manipulating, and
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destroying minimal symbol tables.
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Minimal symbol tables are used to hold some very basic information about
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all defined global symbols (text, data, bss, abs, etc). The only two
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required pieces of information are the symbol's name and the address
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associated with that symbol.
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In many cases, even if a file was compiled with no special options for
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debugging at all, as long as was not stripped it will contain sufficient
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information to build useful minimal symbol tables using this structure.
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Even when a file contains enough debugging information to build a full
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symbol table, these minimal symbols are still useful for quickly mapping
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between names and addresses, and vice versa. They are also sometimes used
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to figure out what full symbol table entries need to be read in. */
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#include "defs.h"
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#include "gdb_string.h"
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#include "symtab.h"
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#include "bfd.h"
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#include "symfile.h"
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#include "objfiles.h"
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#include "demangle.h"
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#include "gdb-stabs.h"
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/* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
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At the end, copy them all into one newly allocated location on an objfile's
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symbol obstack. */
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#define BUNCH_SIZE 127
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struct msym_bunch
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{
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struct msym_bunch *next;
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struct minimal_symbol contents[BUNCH_SIZE];
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};
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/* Bunch currently being filled up.
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The next field points to chain of filled bunches. */
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static struct msym_bunch *msym_bunch;
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/* Number of slots filled in current bunch. */
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static int msym_bunch_index;
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/* Total number of minimal symbols recorded so far for the objfile. */
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static int msym_count;
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/* Prototypes for local functions. */
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static int
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compare_minimal_symbols PARAMS ((const void *, const void *));
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static int
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compact_minimal_symbols PARAMS ((struct minimal_symbol *, int));
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/* Look through all the current minimal symbol tables and find the
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first minimal symbol that matches NAME. If OBJF is non-NULL, limit
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the search to that objfile. If SFILE is non-NULL, limit the search
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to that source file. Returns a pointer to the minimal symbol that
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matches, or NULL if no match is found.
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Note: One instance where there may be duplicate minimal symbols with
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the same name is when the symbol tables for a shared library and the
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symbol tables for an executable contain global symbols with the same
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names (the dynamic linker deals with the duplication). */
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struct minimal_symbol *
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lookup_minimal_symbol (name, sfile, objf)
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register const char *name;
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const char *sfile;
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struct objfile *objf;
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{
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struct objfile *objfile;
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struct minimal_symbol *msymbol;
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struct minimal_symbol *found_symbol = NULL;
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struct minimal_symbol *found_file_symbol = NULL;
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struct minimal_symbol *trampoline_symbol = NULL;
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (sfile != NULL)
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{
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char *p = strrchr (sfile, '/');
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if (p != NULL)
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sfile = p + 1;
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}
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#endif
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for (objfile = object_files;
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objfile != NULL && found_symbol == NULL;
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objfile = objfile -> next)
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{
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if (objf == NULL || objf == objfile)
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{
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for (msymbol = objfile -> msymbols;
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msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
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found_symbol == NULL;
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msymbol++)
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{
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if (SYMBOL_MATCHES_NAME (msymbol, name))
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{
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switch (MSYMBOL_TYPE (msymbol))
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{
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case mst_file_text:
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case mst_file_data:
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case mst_file_bss:
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (sfile == NULL || STREQ (msymbol->filename, sfile))
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found_file_symbol = msymbol;
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#else
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/* We have neither the ability nor the need to
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deal with the SFILE parameter. If we find
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more than one symbol, just return the latest
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one (the user can't expect useful behavior in
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that case). */
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found_file_symbol = msymbol;
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#endif
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break;
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case mst_solib_trampoline:
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/* If a trampoline symbol is found, we prefer to
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keep looking for the *real* symbol. If the
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actual symbol is not found, then we'll use the
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trampoline entry. */
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if (trampoline_symbol == NULL)
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trampoline_symbol = msymbol;
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break;
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case mst_unknown:
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default:
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found_symbol = msymbol;
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break;
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}
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}
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}
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}
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}
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/* External symbols are best. */
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if (found_symbol)
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return found_symbol;
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/* File-local symbols are next best. */
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if (found_file_symbol)
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return found_file_symbol;
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/* Symbols for shared library trampolines are next best. */
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if (trampoline_symbol)
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return trampoline_symbol;
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return NULL;
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}
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/* Look through all the current minimal symbol tables and find the
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first minimal symbol that matches NAME and of text type.
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If OBJF is non-NULL, limit
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the search to that objfile. If SFILE is non-NULL, limit the search
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to that source file. Returns a pointer to the minimal symbol that
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matches, or NULL if no match is found.
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*/
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struct minimal_symbol *
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lookup_minimal_symbol_text (name, sfile, objf)
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register const char *name;
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const char *sfile;
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struct objfile *objf;
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{
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struct objfile *objfile;
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struct minimal_symbol *msymbol;
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struct minimal_symbol *found_symbol = NULL;
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struct minimal_symbol *found_file_symbol = NULL;
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (sfile != NULL)
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{
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char *p = strrchr (sfile, '/');
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if (p != NULL)
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sfile = p + 1;
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}
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#endif
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for (objfile = object_files;
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objfile != NULL && found_symbol == NULL;
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objfile = objfile -> next)
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{
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if (objf == NULL || objf == objfile)
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{
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for (msymbol = objfile -> msymbols;
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msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
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found_symbol == NULL;
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msymbol++)
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{
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if (SYMBOL_MATCHES_NAME (msymbol, name) &&
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(MSYMBOL_TYPE (msymbol) == mst_text ||
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MSYMBOL_TYPE (msymbol) == mst_file_text))
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{
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switch (MSYMBOL_TYPE (msymbol))
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{
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case mst_file_text:
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (sfile == NULL || STREQ (msymbol->filename, sfile))
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found_file_symbol = msymbol;
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#else
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/* We have neither the ability nor the need to
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deal with the SFILE parameter. If we find
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more than one symbol, just return the latest
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one (the user can't expect useful behavior in
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that case). */
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found_file_symbol = msymbol;
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#endif
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break;
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default:
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found_symbol = msymbol;
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break;
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}
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}
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}
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}
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}
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/* External symbols are best. */
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if (found_symbol)
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return found_symbol;
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/* File-local symbols are next best. */
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if (found_file_symbol)
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return found_file_symbol;
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return NULL;
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}
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/* Look through all the current minimal symbol tables and find the
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first minimal symbol that matches NAME and of solib trampoline type.
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If OBJF is non-NULL, limit
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the search to that objfile. If SFILE is non-NULL, limit the search
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to that source file. Returns a pointer to the minimal symbol that
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matches, or NULL if no match is found.
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*/
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struct minimal_symbol *
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lookup_minimal_symbol_solib_trampoline (name, sfile, objf)
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register const char *name;
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const char *sfile;
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struct objfile *objf;
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{
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struct objfile *objfile;
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struct minimal_symbol *msymbol;
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struct minimal_symbol *found_symbol = NULL;
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (sfile != NULL)
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{
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char *p = strrchr (sfile, '/');
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if (p != NULL)
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sfile = p + 1;
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}
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#endif
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for (objfile = object_files;
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objfile != NULL && found_symbol == NULL;
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objfile = objfile -> next)
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{
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if (objf == NULL || objf == objfile)
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{
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for (msymbol = objfile -> msymbols;
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msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
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found_symbol == NULL;
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msymbol++)
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{
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if (SYMBOL_MATCHES_NAME (msymbol, name) &&
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MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
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return msymbol;
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}
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}
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}
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return NULL;
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}
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/* Search through the minimal symbol table for each objfile and find
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the symbol whose address is the largest address that is still less
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than or equal to PC, and matches SECTION (if non-null). Returns a
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pointer to the minimal symbol if such a symbol is found, or NULL if
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PC is not in a suitable range. Note that we need to look through
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ALL the minimal symbol tables before deciding on the symbol that
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comes closest to the specified PC. This is because objfiles can
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overlap, for example objfile A has .text at 0x100 and .data at
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0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */
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struct minimal_symbol *
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lookup_minimal_symbol_by_pc_section (pc, section)
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CORE_ADDR pc;
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asection *section;
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{
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int lo;
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int hi;
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int new;
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struct objfile *objfile;
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struct minimal_symbol *msymbol;
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struct minimal_symbol *best_symbol = NULL;
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/* pc has to be in a known section. This ensures that anything beyond
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the end of the last segment doesn't appear to be part of the last
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function in the last segment. */
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if (find_pc_section (pc) == NULL)
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return NULL;
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for (objfile = object_files;
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objfile != NULL;
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objfile = objfile -> next)
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{
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/* If this objfile has a minimal symbol table, go search it using
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a binary search. Note that a minimal symbol table always consists
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of at least two symbols, a "real" symbol and the terminating
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"null symbol". If there are no real symbols, then there is no
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minimal symbol table at all. */
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if ((msymbol = objfile -> msymbols) != NULL)
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{
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lo = 0;
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hi = objfile -> minimal_symbol_count - 1;
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/* This code assumes that the minimal symbols are sorted by
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ascending address values. If the pc value is greater than or
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equal to the first symbol's address, then some symbol in this
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minimal symbol table is a suitable candidate for being the
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"best" symbol. This includes the last real symbol, for cases
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where the pc value is larger than any address in this vector.
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By iterating until the address associated with the current
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hi index (the endpoint of the test interval) is less than
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or equal to the desired pc value, we accomplish two things:
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(1) the case where the pc value is larger than any minimal
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symbol address is trivially solved, (2) the address associated
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with the hi index is always the one we want when the interation
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terminates. In essence, we are iterating the test interval
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down until the pc value is pushed out of it from the high end.
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Warning: this code is trickier than it would appear at first. */
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/* Should also require that pc is <= end of objfile. FIXME! */
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if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo]))
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{
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while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc)
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{
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/* pc is still strictly less than highest address */
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/* Note "new" will always be >= lo */
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new = (lo + hi) / 2;
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if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) ||
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(lo == new))
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{
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hi = new;
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}
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else
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{
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lo = new;
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}
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}
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/* If we have multiple symbols at the same address, we want
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hi to point to the last one. That way we can find the
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right symbol if it has an index greater than hi. */
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while (hi < objfile -> minimal_symbol_count - 1
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&& (SYMBOL_VALUE_ADDRESS (&msymbol[hi])
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== SYMBOL_VALUE_ADDRESS (&msymbol[hi+1])))
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hi++;
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/* The minimal symbol indexed by hi now is the best one in this
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objfile's minimal symbol table. See if it is the best one
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overall. */
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/* Skip any absolute symbols. This is apparently what adb
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and dbx do, and is needed for the CM-5. There are two
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known possible problems: (1) on ELF, apparently end, edata,
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etc. are absolute. Not sure ignoring them here is a big
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deal, but if we want to use them, the fix would go in
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elfread.c. (2) I think shared library entry points on the
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NeXT are absolute. If we want special handling for this
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it probably should be triggered by a special
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mst_abs_or_lib or some such. */
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while (hi >= 0
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&& msymbol[hi].type == mst_abs)
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--hi;
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/* If "section" specified, skip any symbol from wrong section */
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/* This is the new code that distinguishes it from the old function */
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if (section)
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while (hi >= 0
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&& SYMBOL_BFD_SECTION (&msymbol[hi]) != section)
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--hi;
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if (hi >= 0
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&& ((best_symbol == NULL) ||
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(SYMBOL_VALUE_ADDRESS (best_symbol) <
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SYMBOL_VALUE_ADDRESS (&msymbol[hi]))))
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{
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best_symbol = &msymbol[hi];
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}
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}
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}
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}
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return (best_symbol);
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}
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/* Backward compatibility: search through the minimal symbol table
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for a matching PC (no section given) */
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struct minimal_symbol *
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lookup_minimal_symbol_by_pc (pc)
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CORE_ADDR pc;
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{
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return lookup_minimal_symbol_by_pc_section (pc, find_pc_mapped_section (pc));
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}
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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CORE_ADDR
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find_stab_function_addr (namestring, pst, objfile)
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char *namestring;
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struct partial_symtab *pst;
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struct objfile *objfile;
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{
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struct minimal_symbol *msym;
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char *p;
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int n;
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p = strchr (namestring, ':');
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if (p == NULL)
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p = namestring;
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n = p - namestring;
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p = alloca (n + 1);
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strncpy (p, namestring, n);
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p[n] = 0;
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msym = lookup_minimal_symbol (p, pst->filename, objfile);
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return msym == NULL ? 0 : SYMBOL_VALUE_ADDRESS (msym);
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}
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#endif /* SOFUN_ADDRESS_MAYBE_MISSING */
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/* Return leading symbol character for a BFD. If BFD is NULL,
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return the leading symbol character from the main objfile. */
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static int get_symbol_leading_char PARAMS ((bfd *));
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static int
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get_symbol_leading_char (abfd)
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bfd * abfd;
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{
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if (abfd != NULL)
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return bfd_get_symbol_leading_char (abfd);
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if (symfile_objfile != NULL && symfile_objfile->obfd != NULL)
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return bfd_get_symbol_leading_char (symfile_objfile->obfd);
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return 0;
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}
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/* Prepare to start collecting minimal symbols. Note that presetting
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msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal
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symbol to allocate the memory for the first bunch. */
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void
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init_minimal_symbol_collection ()
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{
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msym_count = 0;
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msym_bunch = NULL;
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msym_bunch_index = BUNCH_SIZE;
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}
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void
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prim_record_minimal_symbol (name, address, ms_type, objfile)
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const char *name;
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CORE_ADDR address;
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enum minimal_symbol_type ms_type;
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struct objfile *objfile;
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{
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int section;
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switch (ms_type)
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{
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case mst_text:
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case mst_file_text:
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case mst_solib_trampoline:
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section = SECT_OFF_TEXT;
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break;
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case mst_data:
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case mst_file_data:
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section = SECT_OFF_DATA;
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break;
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case mst_bss:
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case mst_file_bss:
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section = SECT_OFF_BSS;
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break;
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default:
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section = -1;
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}
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prim_record_minimal_symbol_and_info (name, address, ms_type,
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NULL, section, NULL, objfile);
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}
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/* Record a minimal symbol in the msym bunches. Returns the symbol
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newly created. */
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struct minimal_symbol *
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prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
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bfd_section, objfile)
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const char *name;
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CORE_ADDR address;
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enum minimal_symbol_type ms_type;
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char *info;
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int section;
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asection *bfd_section;
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struct objfile *objfile;
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{
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register struct msym_bunch *new;
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register struct minimal_symbol *msymbol;
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if (ms_type == mst_file_text)
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{
|
||
/* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
|
||
the minimal symbols, because if there is also another symbol
|
||
at the same address (e.g. the first function of the file),
|
||
lookup_minimal_symbol_by_pc would have no way of getting the
|
||
right one. */
|
||
if (name[0] == 'g'
|
||
&& (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0
|
||
|| strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0))
|
||
return (NULL);
|
||
|
||
{
|
||
const char *tempstring = name;
|
||
if (tempstring[0] == get_symbol_leading_char (objfile->obfd))
|
||
++tempstring;
|
||
if (STREQN (tempstring, "__gnu_compiled", 14))
|
||
return (NULL);
|
||
}
|
||
}
|
||
|
||
if (msym_bunch_index == BUNCH_SIZE)
|
||
{
|
||
new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch));
|
||
msym_bunch_index = 0;
|
||
new -> next = msym_bunch;
|
||
msym_bunch = new;
|
||
}
|
||
msymbol = &msym_bunch -> contents[msym_bunch_index];
|
||
SYMBOL_NAME (msymbol) = obsavestring ((char *) name, strlen (name),
|
||
&objfile->symbol_obstack);
|
||
SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown);
|
||
SYMBOL_VALUE_ADDRESS (msymbol) = address;
|
||
SYMBOL_SECTION (msymbol) = section;
|
||
SYMBOL_BFD_SECTION (msymbol) = bfd_section;
|
||
|
||
MSYMBOL_TYPE (msymbol) = ms_type;
|
||
/* FIXME: This info, if it remains, needs its own field. */
|
||
MSYMBOL_INFO (msymbol) = info; /* FIXME! */
|
||
msym_bunch_index++;
|
||
msym_count++;
|
||
OBJSTAT (objfile, n_minsyms++);
|
||
return msymbol;
|
||
}
|
||
|
||
/* Compare two minimal symbols by address and return a signed result based
|
||
on unsigned comparisons, so that we sort into unsigned numeric order. */
|
||
|
||
static int
|
||
compare_minimal_symbols (fn1p, fn2p)
|
||
const PTR fn1p;
|
||
const PTR fn2p;
|
||
{
|
||
register const struct minimal_symbol *fn1;
|
||
register const struct minimal_symbol *fn2;
|
||
|
||
fn1 = (const struct minimal_symbol *) fn1p;
|
||
fn2 = (const struct minimal_symbol *) fn2p;
|
||
|
||
if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2))
|
||
{
|
||
return (-1);
|
||
}
|
||
else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2))
|
||
{
|
||
return (1);
|
||
}
|
||
else
|
||
{
|
||
return (0);
|
||
}
|
||
}
|
||
|
||
/* Discard the currently collected minimal symbols, if any. If we wish
|
||
to save them for later use, we must have already copied them somewhere
|
||
else before calling this function.
|
||
|
||
FIXME: We could allocate the minimal symbol bunches on their own
|
||
obstack and then simply blow the obstack away when we are done with
|
||
it. Is it worth the extra trouble though? */
|
||
|
||
/* ARGSUSED */
|
||
void
|
||
discard_minimal_symbols (foo)
|
||
int foo;
|
||
{
|
||
register struct msym_bunch *next;
|
||
|
||
while (msym_bunch != NULL)
|
||
{
|
||
next = msym_bunch -> next;
|
||
free ((PTR)msym_bunch);
|
||
msym_bunch = next;
|
||
}
|
||
}
|
||
|
||
/* Compact duplicate entries out of a minimal symbol table by walking
|
||
through the table and compacting out entries with duplicate addresses
|
||
and matching names. Return the number of entries remaining.
|
||
|
||
On entry, the table resides between msymbol[0] and msymbol[mcount].
|
||
On exit, it resides between msymbol[0] and msymbol[result_count].
|
||
|
||
When files contain multiple sources of symbol information, it is
|
||
possible for the minimal symbol table to contain many duplicate entries.
|
||
As an example, SVR4 systems use ELF formatted object files, which
|
||
usually contain at least two different types of symbol tables (a
|
||
standard ELF one and a smaller dynamic linking table), as well as
|
||
DWARF debugging information for files compiled with -g.
|
||
|
||
Without compacting, the minimal symbol table for gdb itself contains
|
||
over a 1000 duplicates, about a third of the total table size. Aside
|
||
from the potential trap of not noticing that two successive entries
|
||
identify the same location, this duplication impacts the time required
|
||
to linearly scan the table, which is done in a number of places. So we
|
||
just do one linear scan here and toss out the duplicates.
|
||
|
||
Note that we are not concerned here about recovering the space that
|
||
is potentially freed up, because the strings themselves are allocated
|
||
on the symbol_obstack, and will get automatically freed when the symbol
|
||
table is freed. The caller can free up the unused minimal symbols at
|
||
the end of the compacted region if their allocation strategy allows it.
|
||
|
||
Also note we only go up to the next to last entry within the loop
|
||
and then copy the last entry explicitly after the loop terminates.
|
||
|
||
Since the different sources of information for each symbol may
|
||
have different levels of "completeness", we may have duplicates
|
||
that have one entry with type "mst_unknown" and the other with a
|
||
known type. So if the one we are leaving alone has type mst_unknown,
|
||
overwrite its type with the type from the one we are compacting out. */
|
||
|
||
static int
|
||
compact_minimal_symbols (msymbol, mcount)
|
||
struct minimal_symbol *msymbol;
|
||
int mcount;
|
||
{
|
||
struct minimal_symbol *copyfrom;
|
||
struct minimal_symbol *copyto;
|
||
|
||
if (mcount > 0)
|
||
{
|
||
copyfrom = copyto = msymbol;
|
||
while (copyfrom < msymbol + mcount - 1)
|
||
{
|
||
if (SYMBOL_VALUE_ADDRESS (copyfrom) ==
|
||
SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) &&
|
||
(STREQ (SYMBOL_NAME (copyfrom), SYMBOL_NAME ((copyfrom + 1)))))
|
||
{
|
||
if (MSYMBOL_TYPE((copyfrom + 1)) == mst_unknown)
|
||
{
|
||
MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom);
|
||
}
|
||
copyfrom++;
|
||
}
|
||
else
|
||
{
|
||
*copyto++ = *copyfrom++;
|
||
}
|
||
}
|
||
*copyto++ = *copyfrom++;
|
||
mcount = copyto - msymbol;
|
||
}
|
||
return (mcount);
|
||
}
|
||
|
||
/* Add the minimal symbols in the existing bunches to the objfile's official
|
||
minimal symbol table. In most cases there is no minimal symbol table yet
|
||
for this objfile, and the existing bunches are used to create one. Once
|
||
in a while (for shared libraries for example), we add symbols (e.g. common
|
||
symbols) to an existing objfile.
|
||
|
||
Because of the way minimal symbols are collected, we generally have no way
|
||
of knowing what source language applies to any particular minimal symbol.
|
||
Specifically, we have no way of knowing if the minimal symbol comes from a
|
||
C++ compilation unit or not. So for the sake of supporting cached
|
||
demangled C++ names, we have no choice but to try and demangle each new one
|
||
that comes in. If the demangling succeeds, then we assume it is a C++
|
||
symbol and set the symbol's language and demangled name fields
|
||
appropriately. Note that in order to avoid unnecessary demanglings, and
|
||
allocating obstack space that subsequently can't be freed for the demangled
|
||
names, we mark all newly added symbols with language_auto. After
|
||
compaction of the minimal symbols, we go back and scan the entire minimal
|
||
symbol table looking for these new symbols. For each new symbol we attempt
|
||
to demangle it, and if successful, record it as a language_cplus symbol
|
||
and cache the demangled form on the symbol obstack. Symbols which don't
|
||
demangle are marked as language_unknown symbols, which inhibits future
|
||
attempts to demangle them if we later add more minimal symbols. */
|
||
|
||
void
|
||
install_minimal_symbols (objfile)
|
||
struct objfile *objfile;
|
||
{
|
||
register int bindex;
|
||
register int mcount;
|
||
register struct msym_bunch *bunch;
|
||
register struct minimal_symbol *msymbols;
|
||
int alloc_count;
|
||
register char leading_char;
|
||
|
||
if (msym_count > 0)
|
||
{
|
||
/* Allocate enough space in the obstack, into which we will gather the
|
||
bunches of new and existing minimal symbols, sort them, and then
|
||
compact out the duplicate entries. Once we have a final table,
|
||
we will give back the excess space. */
|
||
|
||
alloc_count = msym_count + objfile->minimal_symbol_count + 1;
|
||
obstack_blank (&objfile->symbol_obstack,
|
||
alloc_count * sizeof (struct minimal_symbol));
|
||
msymbols = (struct minimal_symbol *)
|
||
obstack_base (&objfile->symbol_obstack);
|
||
|
||
/* Copy in the existing minimal symbols, if there are any. */
|
||
|
||
if (objfile->minimal_symbol_count)
|
||
memcpy ((char *)msymbols, (char *)objfile->msymbols,
|
||
objfile->minimal_symbol_count * sizeof (struct minimal_symbol));
|
||
|
||
/* Walk through the list of minimal symbol bunches, adding each symbol
|
||
to the new contiguous array of symbols. Note that we start with the
|
||
current, possibly partially filled bunch (thus we use the current
|
||
msym_bunch_index for the first bunch we copy over), and thereafter
|
||
each bunch is full. */
|
||
|
||
mcount = objfile->minimal_symbol_count;
|
||
leading_char = get_symbol_leading_char (objfile->obfd);
|
||
|
||
for (bunch = msym_bunch; bunch != NULL; bunch = bunch -> next)
|
||
{
|
||
for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++)
|
||
{
|
||
msymbols[mcount] = bunch -> contents[bindex];
|
||
SYMBOL_LANGUAGE (&msymbols[mcount]) = language_auto;
|
||
if (SYMBOL_NAME (&msymbols[mcount])[0] == leading_char)
|
||
{
|
||
SYMBOL_NAME(&msymbols[mcount])++;
|
||
}
|
||
}
|
||
msym_bunch_index = BUNCH_SIZE;
|
||
}
|
||
|
||
/* Sort the minimal symbols by address. */
|
||
|
||
qsort (msymbols, mcount, sizeof (struct minimal_symbol),
|
||
compare_minimal_symbols);
|
||
|
||
/* Compact out any duplicates, and free up whatever space we are
|
||
no longer using. */
|
||
|
||
mcount = compact_minimal_symbols (msymbols, mcount);
|
||
|
||
obstack_blank (&objfile->symbol_obstack,
|
||
(mcount + 1 - alloc_count) * sizeof (struct minimal_symbol));
|
||
msymbols = (struct minimal_symbol *)
|
||
obstack_finish (&objfile->symbol_obstack);
|
||
|
||
/* We also terminate the minimal symbol table with a "null symbol",
|
||
which is *not* included in the size of the table. This makes it
|
||
easier to find the end of the table when we are handed a pointer
|
||
to some symbol in the middle of it. Zero out the fields in the
|
||
"null symbol" allocated at the end of the array. Note that the
|
||
symbol count does *not* include this null symbol, which is why it
|
||
is indexed by mcount and not mcount-1. */
|
||
|
||
SYMBOL_NAME (&msymbols[mcount]) = NULL;
|
||
SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0;
|
||
MSYMBOL_INFO (&msymbols[mcount]) = NULL;
|
||
MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown;
|
||
SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown);
|
||
|
||
/* Attach the minimal symbol table to the specified objfile.
|
||
The strings themselves are also located in the symbol_obstack
|
||
of this objfile. */
|
||
|
||
objfile -> minimal_symbol_count = mcount;
|
||
objfile -> msymbols = msymbols;
|
||
|
||
/* Now walk through all the minimal symbols, selecting the newly added
|
||
ones and attempting to cache their C++ demangled names. */
|
||
|
||
for ( ; mcount-- > 0 ; msymbols++)
|
||
{
|
||
SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Sort all the minimal symbols in OBJFILE. */
|
||
|
||
void
|
||
msymbols_sort (objfile)
|
||
struct objfile *objfile;
|
||
{
|
||
qsort (objfile->msymbols, objfile->minimal_symbol_count,
|
||
sizeof (struct minimal_symbol), compare_minimal_symbols);
|
||
}
|
||
|
||
/* Check if PC is in a shared library trampoline code stub.
|
||
Return minimal symbol for the trampoline entry or NULL if PC is not
|
||
in a trampoline code stub. */
|
||
|
||
struct minimal_symbol *
|
||
lookup_solib_trampoline_symbol_by_pc (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc);
|
||
|
||
if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
|
||
return msymbol;
|
||
return NULL;
|
||
}
|
||
|
||
/* If PC is in a shared library trampoline code stub, return the
|
||
address of the `real' function belonging to the stub.
|
||
Return 0 if PC is not in a trampoline code stub or if the real
|
||
function is not found in the minimal symbol table.
|
||
|
||
We may fail to find the right function if a function with the
|
||
same name is defined in more than one shared library, but this
|
||
is considered bad programming style. We could return 0 if we find
|
||
a duplicate function in case this matters someday. */
|
||
|
||
CORE_ADDR
|
||
find_solib_trampoline_target (pc)
|
||
CORE_ADDR pc;
|
||
{
|
||
struct objfile *objfile;
|
||
struct minimal_symbol *msymbol;
|
||
struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
|
||
|
||
if (tsymbol != NULL)
|
||
{
|
||
ALL_MSYMBOLS (objfile, msymbol)
|
||
{
|
||
if (MSYMBOL_TYPE (msymbol) == mst_text
|
||
&& STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol)))
|
||
return SYMBOL_VALUE_ADDRESS (msymbol);
|
||
}
|
||
}
|
||
return 0;
|
||
}
|
||
|