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-rw-r--r--gdb/ChangeLog10
-rw-r--r--gdb/arm-linux-tdep.c90
-rw-r--r--gdb/config/arm/tm-linux.h4
3 files changed, 100 insertions, 4 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9db2aa5..6257d90 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2000-05-25 Scott Bambrough <scottb@netwinder.org>
+
+ * arm-linux-tdep.c (find_minsym_and_objfile): New.
+ (skip_hurd_resolver): New.
+ (arm_linux_skip_solib_resolver): New.
+ (arm_skip_solib_resolver): Removed.
+
+ * config/arm/tm-linux.h (SKIP_SOLIB_RESOLVER): Changed to use
+ arm_linux_skip_solib_resolver.
+
2000-05-25 Mark Kettenis <kettenis@gnu.org>
* acconfig.h (HAVE_R_FS, HAVE_R_GS): Add.
diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c
index 667fd0b..cbe8c18 100644
--- a/gdb/arm-linux-tdep.c
+++ b/gdb/arm-linux-tdep.c
@@ -24,6 +24,11 @@
#include "gdbtypes.h"
#include "floatformat.h"
+/* For arm_linux_skip_solib_resolver. */
+#include "symtab.h"
+#include "symfile.h"
+#include "objfiles.h"
+
#ifdef GET_LONGJMP_TARGET
/* Figure out where the longjmp will land. We expect that we have
@@ -340,10 +345,91 @@ arm_linux_push_arguments (int nargs, value_ptr * args, CORE_ADDR sp,
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)
+ && 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 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", 0, 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_skip_solib_resolver (CORE_ADDR pc)
+arm_linux_skip_solib_resolver (CORE_ADDR pc)
{
- /* FIXME */
+ CORE_ADDR result;
+
+ /* Plug in functions for other kinds of resolvers here. */
+ result = skip_hurd_resolver (pc);
+ printf ("Result = 0x%08x\n");
+ if (result)
+ return result;
+
+
return 0;
}
diff --git a/gdb/config/arm/tm-linux.h b/gdb/config/arm/tm-linux.h
index af2e809..9dcd666 100644
--- a/gdb/config/arm/tm-linux.h
+++ b/gdb/config/arm/tm-linux.h
@@ -118,8 +118,8 @@ extern CORE_ADDR find_solib_trampoline_target (CORE_ADDR pc);
need to skip over the dynamic linker call. This function decides
when to skip, and where to skip to. See the comments for
SKIP_SOLIB_RESOLVER at the top of infrun.c. */
-extern CORE_ADDR arm_skip_solib_resolver (CORE_ADDR pc);
-#define SKIP_SOLIB_RESOLVER arm_skip_solib_resolver
+extern CORE_ADDR arm_linux_skip_solib_resolver (CORE_ADDR pc);
+#define SKIP_SOLIB_RESOLVER arm_linux_skip_solib_resolver
/* When we call a function in a shared library, and the PLT sends us
into the dynamic linker to find the function's real address, we