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/* GDB routines for manipulating the minimal symbol tables.
Copyright 1992, 1993, 1994, 1995 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., 675 Mass Ave, Cambridge, MA 02139, 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 <string.h>
#include "symtab.h"
#ifndef DONT_USE_BFD
#include "bfd.h"
#endif /* DONT_USE_BFD */
#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. */
#ifdef NeXT
#import <objc/zone.h>
static NXZone *minSymZone;
#define BUNCH_SIZE 510
#else
#define BUNCH_SIZE 127
#endif /* NeXT */
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;
}
#ifdef NeXT
/* Search through the minimal symbol table for an objfile and find the
symbol whose address is the largest address that is still less than or
equal to PC. Returns a pointer to the minimal symbol if such a symbol
is found, or NULL if PC is not in a suitable range. */
struct minimal_symbol *
lookup_minimal_symbol_by_pc_from_objfile (pc, objfile)
register CORE_ADDR pc;
struct objfile *objfile;
{
register int lo;
register int hi;
register int new;
register struct minimal_symbol *msymbol;
register struct minimal_symbol *best_symbol = NULL;
/* 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;
#if 0
hi = objfile -> minimal_symbol_count - 2;
#else
/* Changed this to -1 from -2 because the last null symbol isn't included
* in the minimal_symbol_count field (see comment in install_minimal_symbols).
* This was causing the last symbol to be missed in dynamically loaded code.
*/
hi = objfile -> minimal_symbol_count - 1;
#endif
/* 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 requires 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;
}
}
/* 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. */
best_symbol = &msymbol[hi];
}
}
/* The mst_marker is a pseudo-symbol we've thrown in to the msym table.
* If that was our best match, throw it out.
*/
if (best_symbol && best_symbol->type == mst_marker)
best_symbol = NULL;
/* FIXME FIXME FIXME
* Evidently (I deduce), the last bss symbol in the text segment
* is sometimes bogus, and actually comes from the dyld_stub section.
* If our match is the last bss symbol, test to see if it is from
* the stub section, and if so, toss the match out.
*/
if (best_symbol
#if 0
&& best_symbol[1].type == mst_marker
#else /* MVS fix */
&& best_symbol[1].type != best_symbol->type
#endif
&& [objfile->manager isSymbolStub:pc])
{
best_symbol = NULL;
}
return (best_symbol);
}
/* 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. 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. */
struct minimal_symbol *
lookup_minimal_symbol_by_pc (pc)
register CORE_ADDR pc;
{
register struct objfile *objfile;
register struct minimal_symbol *best_symbol = NULL, *msymbol;
for (objfile = object_files;
objfile != NULL;
objfile = objfile -> next)
{
msymbol = lookup_minimal_symbol_by_pc_from_objfile(pc, objfile);
if (msymbol
&& (!best_symbol ||
(SYMBOL_VALUE_ADDRESS(best_symbol) <
SYMBOL_VALUE_ADDRESS(msymbol))))
{
best_symbol = msymbol;
}
}
return (best_symbol);
}
#else /* NeXT */
/* 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. 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 (pc)
register CORE_ADDR pc;
{
register int lo;
register int hi;
register int new;
register struct objfile *objfile;
register struct minimal_symbol *msymbol;
register struct minimal_symbol *best_symbol = 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 requires 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;
}
}
/* 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 (hi >= 0
&& ((best_symbol == NULL) ||
(SYMBOL_VALUE_ADDRESS (best_symbol) <
SYMBOL_VALUE_ADDRESS (&msymbol[hi]))))
{
best_symbol = &msymbol[hi];
}
}
}
}
return (best_symbol);
}
#endif /* NeXT */
#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 + 1);
strncpy (p, namestring, n);
p[n] = 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;
{
#ifndef NeXT
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;
#else
return '_';
#endif /* NeXT */
}
/* 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 ()
{
#ifdef NeXT
discard_minimal_symbols(0);
minSymZone = NXCreateZone(vm_page_size, vm_page_size, 0);
NXNameZone(minSymZone, "Minimal Symbols");
#endif /* NeXT */
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, 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,
objfile)
const char *name;
CORE_ADDR address;
enum minimal_symbol_type ms_type;
char *info;
int 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;
{
const char *tempstring = name;
#ifndef NeXT
if (tempstring[0] == get_symbol_leading_char (objfile->obfd))
#else
if (tempstring[0] == '_')
#endif /* NeXT */
++tempstring;
if (STREQN (tempstring, "__gnu_compiled", 14))
return;
}
}
if (msym_bunch_index == BUNCH_SIZE)
{
#ifdef NeXT
new = (struct msym_bunch *) NXZoneMalloc(minSymZone,
sizeof (struct msym_bunch));
#else
new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch));
#endif /* NeXT */
msym_bunch_index = 0;
new -> next = msym_bunch;
msym_bunch = new;
}
msymbol = &msym_bunch -> contents[msym_bunch_index];
SYMBOL_NAME (msymbol) = (char *) name;
SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown);
SYMBOL_VALUE_ADDRESS (msymbol) = address;
SYMBOL_SECTION (msymbol) = 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++;
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;
{
#ifdef NeXT
if (minSymZone)
{
NXDestroyZone(minSymZone);
minSymZone = NULL;
}
#else
register struct msym_bunch *next;
while (msym_bunch != NULL)
{
next = msym_bunch -> next;
free ((PTR)msym_bunch);
msym_bunch = next;
}
#endif /* 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;
#ifdef NeXT
#if 0 /* well, but do we really want to do this? */
leading_char = '_'; /* MVS: perhaps we could do better? */
#else
leading_char = '\377'; /* ie. hopefully no character */
#endif /* 0 */ /* let's not strip the leading char for now */
#else /* NeXT */
leading_char = get_symbol_leading_char (objfile->obfd);
#endif /* NeXT */
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;
#ifdef NeXT
combine_minimal_symbols_psymtabs(objfile);
#endif /* NeXT */
/* 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;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.