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[RFA] Add glibc-tdep (was Re: [RFC] Time for a shared linux-nat.cmodule?)
- From: "David S. Miller" <davem at redhat dot com>
- To: msnyder at redhat dot com
- Cc: gdb at sources dot redhat dot com, gdb-patches at sources dot redhat dot com
- Date: Wed, 24 Apr 2002 08:18:05 -0700 (PDT)
- Subject: [RFA] Add glibc-tdep (was Re: [RFC] Time for a shared linux-nat.cmodule?)
- References: <3CC5C242.D975892F@redhat.com><20020423.215351.41174202.davem@redhat.com>
From: "David S. Miller" <davem@redhat.com>
Date: Tue, 23 Apr 2002 21:53:51 -0700 (PDT)
From: Michael Snyder <msnyder@redhat.com>
Date: Tue, 23 Apr 2002 13:21:22 -0700
I'm wondering if it isn't time to create a linux-nat.c module,
shared by all host architectures, into which we can move
some of this code instead of maintaining separate, duplicate
versions.
The code won't be even Linux specific, I think.
For example the dynamic linker checks are glibc specific.
The commentary refers to it as the "Hurd" resolver, but
in fact it is more of a glibc thing than anything else.
To this end I've implemented the following patch, and tested
builds of arm-linux and i386-linux targets.
Any objections?
2002-04-24 David S. Miller <davem@redhat.com>
* glibc-tdep.c, glibc-tdep.h: New files.
* config/arm/linux.mt (TDEPFILES): Add glibc-tdep.o
* config/i386/linux.mt (TDEPFILES): Likewise.
* i386-linux-tdep.c (glibc-tdep.h): Include.
(find_minsym_and_objfile, skip_hurd_resolver): Delete.
(i386_linux_skip_solib_resolver): Call glibc_skip_solib_resolver.
* arm-linux-tdep.c (glibc-tdep.h): Include.
(find_minsym_and_objfile, skip_hurd_resolver): Delete.
(arm_linux_skip_solib_resolver): Call glibc_skip_solib_resolver.
* Makefile.in (ALLDEPFILES): Add glibc-tdep.c
(glibc-tdep.o): Add dependencies.
(arm-linux-tdep.o): Update dependencies.
(i386-linux-tdep.o): Likewise.
--- ./config/arm/linux.mt.~1~ Wed Feb 13 21:48:32 2002
+++ ./config/arm/linux.mt Tue Apr 23 23:57:25 2002
@@ -1,5 +1,5 @@
# Target: ARM based machine running GNU/Linux
TM_FILE= tm-linux.h
-TDEPFILES= arm-tdep.o arm-linux-tdep.o solib.o solib-svr4.o solib-legacy.o
+TDEPFILES= arm-tdep.o arm-linux-tdep.o glibc-tdep.o solib.o solib-svr4.o solib-legacy.o
GDBSERVER_DEPFILES = linux-low.o linux-arm-low.o reg-arm.o
--- ./config/i386/linux.mt.~1~ Wed Feb 13 21:48:33 2002
+++ ./config/i386/linux.mt Tue Apr 23 23:57:16 2002
@@ -1,5 +1,5 @@
# Target: Intel 386 running GNU/Linux
-TDEPFILES= i386-tdep.o i386-linux-tdep.o i387-tdep.o \
+TDEPFILES= i386-tdep.o i386-linux-tdep.o glibc-tdep.o i387-tdep.o \
solib.o solib-svr4.o solib-legacy.o
TM_FILE= tm-linux.h
--- ./glibc-tdep.h.~1~ Wed Apr 24 08:20:15 2002
+++ ./glibc-tdep.h Tue Apr 23 23:54:45 2002
@@ -0,0 +1,22 @@
+/* Target dependent code for GDB on systems using GLIBC.
+ Copyright 2002 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 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. */
+
+CORE_ADDR
+glibc_skip_solib_resolver (CORE_ADDR);
--- ./glibc-tdep.c.~1~ Wed Apr 24 08:20:16 2002
+++ ./glibc-tdep.c Wed Apr 24 08:02:28 2002
@@ -0,0 +1,116 @@
+/* GLIBC target support.
+ Copyright 2002 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 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. */
+
+#include "defs.h"
+#include "frame.h"
+
+/* For glibc_skip_solib_resolver. */
+#include "symtab.h"
+#include "symfile.h"
+#include "objfiles.h"
+
+#include "glibc-tdep.h"
+
+/* Calling functions in shared libraries. */
+
+/* Find the minimal symbol named NAME, and return both the minsym
+ struct and its objfile. This probably ought to be in minsym.c, but
+ everything there is trying to deal with things like C++ and
+ SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may
+ be considered too special-purpose for general consumption. */
+
+static struct minimal_symbol *
+find_minsym_and_objfile (char *name, struct objfile **objfile_p)
+{
+ struct objfile *objfile;
+
+ ALL_OBJFILES (objfile)
+ {
+ struct minimal_symbol *msym;
+
+ ALL_OBJFILE_MSYMBOLS (objfile, msym)
+ {
+ if (SYMBOL_NAME (msym)
+ && STREQ (SYMBOL_NAME (msym), name))
+ {
+ *objfile_p = objfile;
+ return msym;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static CORE_ADDR
+skip_hurd_resolver (CORE_ADDR pc)
+{
+ /* The HURD dynamic linker is part of the GNU C library, so many
+ GNU/Linux distributions use it. (All ELF versions, as far as I
+ know.) An unresolved PLT entry points to "_dl_runtime_resolve",
+ which calls "fixup" to patch the PLT, and then passes control to
+ the function.
+
+ We look for the symbol `_dl_runtime_resolve', and find `fixup' in
+ the same objfile. If we are at the entry point of `fixup', then
+ we set a breakpoint at the return address (at the top of the
+ stack), and continue.
+
+ It's kind of gross to do all these checks every time we're
+ called, since they don't change once the executable has gotten
+ started. But this is only a temporary hack --- upcoming versions
+ of GNU/Linux will provide a portable, efficient interface for
+ debugging programs that use shared libraries. */
+
+ struct objfile *objfile;
+ struct minimal_symbol *resolver
+ = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile);
+
+ if (resolver)
+ {
+ struct minimal_symbol *fixup
+ = lookup_minimal_symbol ("fixup", NULL, objfile);
+
+ if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
+ return (SAVED_PC_AFTER_CALL (get_current_frame ()));
+ }
+
+ return 0;
+}
+
+/* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c.
+ This function:
+ 1) decides whether a PLT has sent us into the linker to resolve
+ a function reference, and
+ 2) if so, tells us where to set a temporary breakpoint that will
+ trigger when the dynamic linker is done. */
+
+CORE_ADDR
+glibc_skip_solib_resolver (CORE_ADDR pc)
+{
+ CORE_ADDR result;
+
+ /* Plug in functions for other kinds of resolvers here. */
+ result = skip_hurd_resolver (pc);
+ if (result)
+ return result;
+
+ return 0;
+}
--- ./i386-linux-tdep.c.~1~ Sun Feb 24 14:31:19 2002
+++ ./i386-linux-tdep.c Tue Apr 23 23:55:40 2002
@@ -33,6 +33,8 @@
#include "solib-svr4.h" /* For struct link_map_offsets. */
+#include "glibc-tdep.h"
+
/* Return the name of register REG. */
char *
@@ -403,89 +405,10 @@ i386_linux_write_pc (CORE_ADDR pc, ptid_
/* Calling functions in shared libraries. */
-/* Find the minimal symbol named NAME, and return both the minsym
- struct and its objfile. This probably ought to be in minsym.c, but
- everything there is trying to deal with things like C++ and
- SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may
- be considered too special-purpose for general consumption. */
-
-static struct minimal_symbol *
-find_minsym_and_objfile (char *name, struct objfile **objfile_p)
-{
- struct objfile *objfile;
-
- ALL_OBJFILES (objfile)
- {
- struct minimal_symbol *msym;
-
- ALL_OBJFILE_MSYMBOLS (objfile, msym)
- {
- if (SYMBOL_NAME (msym)
- && STREQ (SYMBOL_NAME (msym), name))
- {
- *objfile_p = objfile;
- return msym;
- }
- }
- }
-
- return 0;
-}
-
-static CORE_ADDR
-skip_hurd_resolver (CORE_ADDR pc)
-{
- /* The HURD dynamic linker is part of the GNU C library, so many
- GNU/Linux distributions use it. (All ELF versions, as far as I
- know.) An unresolved PLT entry points to "_dl_runtime_resolve",
- which calls "fixup" to patch the PLT, and then passes control to
- the function.
-
- We look for the symbol `_dl_runtime_resolve', and find `fixup' in
- the same objfile. If we are at the entry point of `fixup', then
- we set a breakpoint at the return address (at the top of the
- stack), and continue.
-
- It's kind of gross to do all these checks every time we're
- called, since they don't change once the executable has gotten
- started. But this is only a temporary hack --- upcoming versions
- of GNU/Linux will provide a portable, efficient interface for
- debugging programs that use shared libraries. */
-
- struct objfile *objfile;
- struct minimal_symbol *resolver
- = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile);
-
- if (resolver)
- {
- struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", NULL, objfile);
-
- if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
- return (SAVED_PC_AFTER_CALL (get_current_frame ()));
- }
-
- return 0;
-}
-
-/* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c.
- This function:
- 1) decides whether a PLT has sent us into the linker to resolve
- a function reference, and
- 2) if so, tells us where to set a temporary breakpoint that will
- trigger when the dynamic linker is done. */
-
CORE_ADDR
i386_linux_skip_solib_resolver (CORE_ADDR pc)
{
- CORE_ADDR result;
-
- /* Plug in functions for other kinds of resolvers here. */
- result = skip_hurd_resolver (pc);
- if (result)
- return result;
-
- return 0;
+ glibc_skip_solib_resolver (pc);
}
/* Fetch (and possibly build) an appropriate link_map_offsets
--- ./arm-linux-tdep.c.~1~ Sat Feb 23 14:17:11 2002
+++ ./arm-linux-tdep.c Tue Apr 23 23:56:47 2002
@@ -29,6 +29,7 @@
#include "doublest.h"
#include "arm-tdep.h"
+#include "glibc-tdep.h"
/* For shared library handling. */
#include "symtab.h"
@@ -345,91 +346,10 @@ arm_linux_push_arguments (int nargs, str
with. Before the fixup/resolver code returns, it actually calls
the requested function and repairs &GOT[n+3]. */
-/* Find the minimal symbol named NAME, and return both the minsym
- struct and its objfile. This probably ought to be in minsym.c, but
- everything there is trying to deal with things like C++ and
- SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may
- be considered too special-purpose for general consumption. */
-
-static struct minimal_symbol *
-find_minsym_and_objfile (char *name, struct objfile **objfile_p)
-{
- struct objfile *objfile;
-
- ALL_OBJFILES (objfile)
- {
- struct minimal_symbol *msym;
-
- ALL_OBJFILE_MSYMBOLS (objfile, msym)
- {
- if (SYMBOL_NAME (msym)
- && strcmp (SYMBOL_NAME (msym), name) == 0)
- {
- *objfile_p = objfile;
- return msym;
- }
- }
- }
-
- return 0;
-}
-
-
-static CORE_ADDR
-skip_hurd_resolver (CORE_ADDR pc)
-{
- /* The HURD dynamic linker is part of the GNU C library, so many
- GNU/Linux distributions use it. (All ELF versions, as far as I
- know.) An unresolved PLT entry points to "_dl_runtime_resolve",
- which calls "fixup" to patch the PLT, and then passes control to
- the function.
-
- We look for the symbol `_dl_runtime_resolve', and find `fixup' in
- the same objfile. If we are at the entry point of `fixup', then
- we set a breakpoint at the return address (at the top of the
- stack), and continue.
-
- It's kind of gross to do all these checks every time we're
- called, since they don't change once the executable has gotten
- started. But this is only a temporary hack --- upcoming versions
- of GNU/Linux will provide a portable, efficient interface for
- debugging programs that use shared libraries. */
-
- struct objfile *objfile;
- struct minimal_symbol *resolver
- = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile);
-
- if (resolver)
- {
- struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", NULL, objfile);
-
- if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
- return (SAVED_PC_AFTER_CALL (get_current_frame ()));
- }
-
- return 0;
-}
-
-/* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c.
- This function:
- 1) decides whether a PLT has sent us into the linker to resolve
- a function reference, and
- 2) if so, tells us where to set a temporary breakpoint that will
- trigger when the dynamic linker is done. */
-
CORE_ADDR
arm_linux_skip_solib_resolver (CORE_ADDR pc)
{
- CORE_ADDR result;
-
- /* Plug in functions for other kinds of resolvers here. */
- result = skip_hurd_resolver (pc);
-
- if (result)
- return result;
-
- return 0;
+ return glibc_skip_solib_resolver (pc);
}
/* The constants below were determined by examining the following files
--- ./Makefile.in.~1~ Mon Apr 22 17:53:30 2002
+++ ./Makefile.in Wed Apr 24 08:02:43 2002
@@ -1185,6 +1185,7 @@ ALLDEPFILES = 29k-share/udi/udip2soc.c 2
coff-solib.c \
core-sol2.c core-regset.c core-aout.c corelow.c \
dcache.c delta68-nat.c dpx2-nat.c dstread.c exec.c fork-child.c \
+ glibc-tdep.c \
go32-nat.c h8300-tdep.c h8500-tdep.c \
hp300ux-nat.c hppa-tdep.c hppab-nat.c hppah-nat.c hpread.c \
i386-tdep.c i386b-nat.c i386mach-nat.c i386v-nat.c i386-linux-nat.c \
@@ -1263,7 +1264,8 @@ arm-linux-nat.o: arm-linux-nat.c $(defs_
$(gdb_string_h) $(regcache_h) arm-tdep.h
arm-linux-tdep.o: arm-linux-tdep.c $(defs_h) $(target_h) $(value_h) \
- $(gdbtypes_h) $(floatformat_h) $(regcache_h) $(doublest_h) arm-tdep.h
+ $(gdbtypes_h) $(floatformat_h) $(regcache_h) $(doublest_h) arm-tdep.h \
+ $(srcdir)/glibc-tdep.h
arm-tdep.o: arm-tdep.c $(defs_h) $(frame_h) $(inferior_h) $(gdbcmd_h) \
$(gdbcore_h) $(gdb_string_h) $(dis_asm_h) $(regcache_h) $(doublest_h) \
@@ -1522,6 +1524,9 @@ gdbtk-wrapper.o: $(srcdir)/gdbtk/generic
$(CC) -c $(INTERNAL_CFLAGS) $(IDE_CFLAGS) $(GDBTK_CFLAGS)\
$(srcdir)/gdbtk/generic/gdbtk-wrapper.c
+glibc-tdep.o: glibc-tdep.c $(defs_h) $(frame_h) $(symtab_h) \
+ $(symfile_h) $(objfiles_h) $(srcdir)/glibc-tdep.h
+
v850ice.o: v850ice.c $(defs_h) $(symtab_h) $(inferior_h) $(command_h) \
$(frame_h) $(breakpoint_h) $(gdbcore_h) $(value_h) $(symfile_h) \
$(gdb_string_h) $(target_h) $(objfiles_h) $(regcache_h)
@@ -1618,7 +1623,7 @@ i386-linux-nat.o: i386-linux-nat.c $(def
$(symtab_h) $(symfile_h) $(objfiles_h) $(regcache_h)
i386-linux-tdep.o: i386-linux-tdep.c $(defs_h) $(gdbcore_h) $(frame_h) \
- $(value_h) $(regcache_h)
+ $(value_h) $(regcache_h) $(srcdir)/glibc-tdep.h
i386v4-nat.o: i386v4-nat.c $(defs_h) $(regcache_h)