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authorStan Shebs <shebs@codesourcery.com>1999-04-16 01:34:07 +0000
committerStan Shebs <shebs@codesourcery.com>1999-04-16 01:34:07 +0000
commit071ea11e85eb9d529cc5eb3d35f6247466a21b99 (patch)
tree5deda65b8d7b04d1f4cbc534c3206d328e1267ec /gdb/minsyms.c
parent1730ec6b1848f0f32154277f788fb29f88d8475b (diff)
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Initial creation of sourceware repository
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-/* GDB routines for manipulating the minimal symbol tables.
- Copyright 1992, 93, 94, 96, 97, 1998 Free Software Foundation, Inc.
- Contributed by Cygnus Support, using pieces from other GDB modules.
-
-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 2 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, write to the Free Software
-Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
-
-
-/* This file contains support routines for creating, manipulating, and
- destroying minimal symbol tables.
-
- Minimal symbol tables are used to hold some very basic information about
- all defined global symbols (text, data, bss, abs, etc). The only two
- required pieces of information are the symbol's name and the address
- associated with that symbol.
-
- In many cases, even if a file was compiled with no special options for
- debugging at all, as long as was not stripped it will contain sufficient
- information to build useful minimal symbol tables using this structure.
-
- Even when a file contains enough debugging information to build a full
- symbol table, these minimal symbols are still useful for quickly mapping
- between names and addresses, and vice versa. They are also sometimes used
- to figure out what full symbol table entries need to be read in. */
-
-
-#include "defs.h"
-#include "gdb_string.h"
-#include "symtab.h"
-#include "bfd.h"
-#include "symfile.h"
-#include "objfiles.h"
-#include "demangle.h"
-#include "gdb-stabs.h"
-
-/* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
- At the end, copy them all into one newly allocated location on an objfile's
- symbol obstack. */
-
-#define BUNCH_SIZE 127
-
-struct msym_bunch
-{
- struct msym_bunch *next;
- struct minimal_symbol contents[BUNCH_SIZE];
-};
-
-/* Bunch currently being filled up.
- The next field points to chain of filled bunches. */
-
-static struct msym_bunch *msym_bunch;
-
-/* Number of slots filled in current bunch. */
-
-static int msym_bunch_index;
-
-/* Total number of minimal symbols recorded so far for the objfile. */
-
-static int msym_count;
-
-/* Prototypes for local functions. */
-
-static int
-compare_minimal_symbols PARAMS ((const void *, const void *));
-
-static int
-compact_minimal_symbols PARAMS ((struct minimal_symbol *, int));
-
-/* Look through all the current minimal symbol tables and find the
- first minimal symbol that matches NAME. If OBJF is non-NULL, limit
- the search to that objfile. If SFILE is non-NULL, limit the search
- to that source file. Returns a pointer to the minimal symbol that
- matches, or NULL if no match is found.
-
- Note: One instance where there may be duplicate minimal symbols with
- the same name is when the symbol tables for a shared library and the
- symbol tables for an executable contain global symbols with the same
- names (the dynamic linker deals with the duplication). */
-
-struct minimal_symbol *
-lookup_minimal_symbol (name, sfile, objf)
- register const char *name;
- const char *sfile;
- struct objfile *objf;
-{
- struct objfile *objfile;
- struct minimal_symbol *msymbol;
- struct minimal_symbol *found_symbol = NULL;
- struct minimal_symbol *found_file_symbol = NULL;
- struct minimal_symbol *trampoline_symbol = NULL;
-
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (sfile != NULL)
- {
- char *p = strrchr (sfile, '/');
- if (p != NULL)
- sfile = p + 1;
- }
-#endif
-
- for (objfile = object_files;
- objfile != NULL && found_symbol == NULL;
- objfile = objfile -> next)
- {
- if (objf == NULL || objf == objfile)
- {
- for (msymbol = objfile -> msymbols;
- msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
- found_symbol == NULL;
- msymbol++)
- {
- if (SYMBOL_MATCHES_NAME (msymbol, name))
- {
- switch (MSYMBOL_TYPE (msymbol))
- {
- case mst_file_text:
- case mst_file_data:
- case mst_file_bss:
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (sfile == NULL || STREQ (msymbol->filename, sfile))
- found_file_symbol = msymbol;
-#else
- /* We have neither the ability nor the need to
- deal with the SFILE parameter. If we find
- more than one symbol, just return the latest
- one (the user can't expect useful behavior in
- that case). */
- found_file_symbol = msymbol;
-#endif
- break;
-
- case mst_solib_trampoline:
-
- /* If a trampoline symbol is found, we prefer to
- keep looking for the *real* symbol. If the
- actual symbol is not found, then we'll use the
- trampoline entry. */
- if (trampoline_symbol == NULL)
- trampoline_symbol = msymbol;
- break;
-
- case mst_unknown:
- default:
- found_symbol = msymbol;
- break;
- }
- }
- }
- }
- }
- /* External symbols are best. */
- if (found_symbol)
- return found_symbol;
-
- /* File-local symbols are next best. */
- if (found_file_symbol)
- return found_file_symbol;
-
- /* Symbols for shared library trampolines are next best. */
- if (trampoline_symbol)
- return trampoline_symbol;
-
- return NULL;
-}
-
-/* Look through all the current minimal symbol tables and find the
- first minimal symbol that matches NAME and of text type.
- If OBJF is non-NULL, limit
- the search to that objfile. If SFILE is non-NULL, limit the search
- to that source file. Returns a pointer to the minimal symbol that
- matches, or NULL if no match is found.
-*/
-
-struct minimal_symbol *
-lookup_minimal_symbol_text (name, sfile, objf)
- register const char *name;
- const char *sfile;
- struct objfile *objf;
-{
- struct objfile *objfile;
- struct minimal_symbol *msymbol;
- struct minimal_symbol *found_symbol = NULL;
- struct minimal_symbol *found_file_symbol = NULL;
-
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (sfile != NULL)
- {
- char *p = strrchr (sfile, '/');
- if (p != NULL)
- sfile = p + 1;
- }
-#endif
-
- for (objfile = object_files;
- objfile != NULL && found_symbol == NULL;
- objfile = objfile -> next)
- {
- if (objf == NULL || objf == objfile)
- {
- for (msymbol = objfile -> msymbols;
- msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
- found_symbol == NULL;
- msymbol++)
- {
- if (SYMBOL_MATCHES_NAME (msymbol, name) &&
- (MSYMBOL_TYPE (msymbol) == mst_text ||
- MSYMBOL_TYPE (msymbol) == mst_file_text))
- {
- switch (MSYMBOL_TYPE (msymbol))
- {
- case mst_file_text:
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (sfile == NULL || STREQ (msymbol->filename, sfile))
- found_file_symbol = msymbol;
-#else
- /* We have neither the ability nor the need to
- deal with the SFILE parameter. If we find
- more than one symbol, just return the latest
- one (the user can't expect useful behavior in
- that case). */
- found_file_symbol = msymbol;
-#endif
- break;
- default:
- found_symbol = msymbol;
- break;
- }
- }
- }
- }
- }
- /* External symbols are best. */
- if (found_symbol)
- return found_symbol;
-
- /* File-local symbols are next best. */
- if (found_file_symbol)
- return found_file_symbol;
-
- return NULL;
-}
-
-/* Look through all the current minimal symbol tables and find the
- first minimal symbol that matches NAME and of solib trampoline type.
- If OBJF is non-NULL, limit
- the search to that objfile. If SFILE is non-NULL, limit the search
- to that source file. Returns a pointer to the minimal symbol that
- matches, or NULL if no match is found.
-*/
-
-struct minimal_symbol *
-lookup_minimal_symbol_solib_trampoline (name, sfile, objf)
- register const char *name;
- const char *sfile;
- struct objfile *objf;
-{
- struct objfile *objfile;
- struct minimal_symbol *msymbol;
- struct minimal_symbol *found_symbol = NULL;
-
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
- if (sfile != NULL)
- {
- char *p = strrchr (sfile, '/');
- if (p != NULL)
- sfile = p + 1;
- }
-#endif
-
- for (objfile = object_files;
- objfile != NULL && found_symbol == NULL;
- objfile = objfile -> next)
- {
- if (objf == NULL || objf == objfile)
- {
- for (msymbol = objfile -> msymbols;
- msymbol != NULL && SYMBOL_NAME (msymbol) != NULL &&
- found_symbol == NULL;
- msymbol++)
- {
- if (SYMBOL_MATCHES_NAME (msymbol, name) &&
- MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
- return msymbol;
- }
- }
- }
-
- return NULL;
-}
-
-
-/* Search through the minimal symbol table for each objfile and find
- the symbol whose address is the largest address that is still less
- than or equal to PC, and matches SECTION (if non-null). Returns a
- pointer to the minimal symbol if such a symbol is found, or NULL if
- PC is not in a suitable range. Note that we need to look through
- ALL the minimal symbol tables before deciding on the symbol that
- comes closest to the specified PC. This is because objfiles can
- overlap, for example objfile A has .text at 0x100 and .data at
- 0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */
-
-struct minimal_symbol *
-lookup_minimal_symbol_by_pc_section (pc, section)
- CORE_ADDR pc;
- asection *section;
-{
- int lo;
- int hi;
- int new;
- struct objfile *objfile;
- struct minimal_symbol *msymbol;
- struct minimal_symbol *best_symbol = NULL;
-
- /* pc has to be in a known section. This ensures that anything beyond
- the end of the last segment doesn't appear to be part of the last
- function in the last segment. */
- if (find_pc_section (pc) == NULL)
- return NULL;
-
- for (objfile = object_files;
- objfile != NULL;
- objfile = objfile -> next)
- {
- /* If this objfile has a minimal symbol table, go search it using
- a binary search. Note that a minimal symbol table always consists
- of at least two symbols, a "real" symbol and the terminating
- "null symbol". If there are no real symbols, then there is no
- minimal symbol table at all. */
-
- if ((msymbol = objfile -> msymbols) != NULL)
- {
- lo = 0;
- hi = objfile -> minimal_symbol_count - 1;
-
- /* This code assumes that the minimal symbols are sorted by
- ascending address values. If the pc value is greater than or
- equal to the first symbol's address, then some symbol in this
- minimal symbol table is a suitable candidate for being the
- "best" symbol. This includes the last real symbol, for cases
- where the pc value is larger than any address in this vector.
-
- By iterating until the address associated with the current
- hi index (the endpoint of the test interval) is less than
- or equal to the desired pc value, we accomplish two things:
- (1) the case where the pc value is larger than any minimal
- symbol address is trivially solved, (2) the address associated
- with the hi index is always the one we want when the interation
- terminates. In essence, we are iterating the test interval
- down until the pc value is pushed out of it from the high end.
-
- Warning: this code is trickier than it would appear at first. */
-
- /* Should also require that pc is <= end of objfile. FIXME! */
- if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo]))
- {
- while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc)
- {
- /* pc is still strictly less than highest address */
- /* Note "new" will always be >= lo */
- new = (lo + hi) / 2;
- if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) ||
- (lo == new))
- {
- hi = new;
- }
- else
- {
- lo = new;
- }
- }
-
- /* If we have multiple symbols at the same address, we want
- hi to point to the last one. That way we can find the
- right symbol if it has an index greater than hi. */
- while (hi < objfile -> minimal_symbol_count - 1
- && (SYMBOL_VALUE_ADDRESS (&msymbol[hi])
- == SYMBOL_VALUE_ADDRESS (&msymbol[hi+1])))
- hi++;
-
- /* The minimal symbol indexed by hi now is the best one in this
- objfile's minimal symbol table. See if it is the best one
- overall. */
-
- /* Skip any absolute symbols. This is apparently what adb
- and dbx do, and is needed for the CM-5. There are two
- known possible problems: (1) on ELF, apparently end, edata,
- etc. are absolute. Not sure ignoring them here is a big
- deal, but if we want to use them, the fix would go in
- elfread.c. (2) I think shared library entry points on the
- NeXT are absolute. If we want special handling for this
- it probably should be triggered by a special
- mst_abs_or_lib or some such. */
- while (hi >= 0
- && msymbol[hi].type == mst_abs)
- --hi;
-
- /* If "section" specified, skip any symbol from wrong section */
- /* This is the new code that distinguishes it from the old function */
- if (section)
- while (hi >= 0
- && SYMBOL_BFD_SECTION (&msymbol[hi]) != section)
- --hi;
-
- if (hi >= 0
- && ((best_symbol == NULL) ||
- (SYMBOL_VALUE_ADDRESS (best_symbol) <
- SYMBOL_VALUE_ADDRESS (&msymbol[hi]))))
- {
- best_symbol = &msymbol[hi];
- }
- }
- }
- }
- return (best_symbol);
-}
-
-/* Backward compatibility: search through the minimal symbol table
- for a matching PC (no section given) */
-
-struct minimal_symbol *
-lookup_minimal_symbol_by_pc (pc)
- CORE_ADDR pc;
-{
- return lookup_minimal_symbol_by_pc_section (pc, find_pc_mapped_section (pc));
-}
-
-#ifdef SOFUN_ADDRESS_MAYBE_MISSING
-CORE_ADDR
-find_stab_function_addr (namestring, pst, objfile)
- char *namestring;
- struct partial_symtab *pst;
- struct objfile *objfile;
-{
- struct minimal_symbol *msym;
- char *p;
- int n;
-
- p = strchr (namestring, ':');
- if (p == NULL)
- p = namestring;
- n = p - namestring;
- p = alloca (n + 2);
- strncpy (p, namestring, n);
- p[n] = 0;
-
- msym = lookup_minimal_symbol (p, pst->filename, objfile);
- if (msym == NULL)
- {
- /* Sun Fortran appends an underscore to the minimal symbol name,
- try again with an appended underscore if the minimal symbol
- was not found. */
- p[n] = '_';
- p[n + 1] = 0;
- msym = lookup_minimal_symbol (p, pst->filename, objfile);
- }
- return msym == NULL ? 0 : SYMBOL_VALUE_ADDRESS (msym);
-}
-#endif /* SOFUN_ADDRESS_MAYBE_MISSING */
-
-
-/* Return leading symbol character for a BFD. If BFD is NULL,
- return the leading symbol character from the main objfile. */
-
-static int get_symbol_leading_char PARAMS ((bfd *));
-
-static int
-get_symbol_leading_char (abfd)
- bfd * abfd;
-{
- if (abfd != NULL)
- return bfd_get_symbol_leading_char (abfd);
- if (symfile_objfile != NULL && symfile_objfile->obfd != NULL)
- return bfd_get_symbol_leading_char (symfile_objfile->obfd);
- return 0;
-}
-
-/* Prepare to start collecting minimal symbols. Note that presetting
- msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal
- symbol to allocate the memory for the first bunch. */
-
-void
-init_minimal_symbol_collection ()
-{
- msym_count = 0;
- msym_bunch = NULL;
- msym_bunch_index = BUNCH_SIZE;
-}
-
-void
-prim_record_minimal_symbol (name, address, ms_type, objfile)
- const char *name;
- CORE_ADDR address;
- enum minimal_symbol_type ms_type;
- struct objfile *objfile;
-{
- int section;
-
- switch (ms_type)
- {
- case mst_text:
- case mst_file_text:
- case mst_solib_trampoline:
- section = SECT_OFF_TEXT;
- break;
- case mst_data:
- case mst_file_data:
- section = SECT_OFF_DATA;
- break;
- case mst_bss:
- case mst_file_bss:
- section = SECT_OFF_BSS;
- break;
- default:
- section = -1;
- }
-
- prim_record_minimal_symbol_and_info (name, address, ms_type,
- NULL, section, NULL, objfile);
-}
-
-/* Record a minimal symbol in the msym bunches. Returns the symbol
- newly created. */
-
-struct minimal_symbol *
-prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
- bfd_section, objfile)
- const char *name;
- CORE_ADDR address;
- enum minimal_symbol_type ms_type;
- char *info;
- int section;
- asection *bfd_section;
- struct objfile *objfile;
-{
- register struct msym_bunch *new;
- register struct minimal_symbol *msymbol;
-
- if (ms_type == mst_file_text)
- {
- /* 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.
- Within groups with the same address, sort by name. */
-
-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); /* addr 1 is less than addr 2 */
- }
- else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2))
- {
- return (1); /* addr 1 is greater than addr 2 */
- }
- else /* addrs are equal: sort by name */
- {
- char *name1 = SYMBOL_NAME (fn1);
- char *name2 = SYMBOL_NAME (fn2);
-
- if (name1 && name2) /* both have names */
- return strcmp (name1, name2);
- else if (name2)
- return 1; /* fn1 has no name, so it is "less" */
- else if (name1) /* fn2 has no name, so it is "less" */
- return -1;
- else
- return (0); /* neither has a name, so they're equal. */
- }
-}
-
-/* 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;
-}
-