2004-03-24 Andrew Cagney <cagney@redhat.com>

	* tramp-frame.h (TRAMP_SENTINEL_INSN): Define, document.
	* tramp-frame.c: Include "gdb_assert.h".
	(tramp_frame_start): Use TRAMP_SENTINEL_INSN.  Use ULONGEST and
	correct sizeof.
	(tramp_frame_append): Validate the tramp frame's instructions.
	* Makefile.in (tramp-frame.o): Update dependencies.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 312afc3..512129e 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,12 @@
+2004-03-24  Andrew Cagney  <cagney@redhat.com>
+
+       * tramp-frame.h (TRAMP_SENTINEL_INSN): Define, document.
+       * tramp-frame.c: Include "gdb_assert.h".
+       (tramp_frame_start): Use TRAMP_SENTINEL_INSN.  Use ULONGEST and
+       correct sizeof.
+       (tramp_frame_append): Validate the tramp frame's instructions.
+       * Makefile.in (tramp-frame.o): Update dependencies.
+
 2004-03-23  Andrew Cagney  <cagney@redhat.com>
 
        * trad-frame.h (trad_frame_set_reg_addr): Declare.

diff --git a/gdb/tramp-frame.c b/gdb/tramp-frame.c
index 7a8057e..ee3635f 100644 (file)
--- a/gdb/tramp-frame.c
+++ b/gdb/tramp-frame.c
@@ -28,6 +28,7 @@
 #include "target.h"
 #include "trad-frame.h"
 #include "frame-base.h"
+#include "gdb_assert.h"
 
 struct frame_data
 {
@@ -89,15 +90,15 @@ tramp_frame_start (CORE_ADDR pc, const struct tramp_frame *tramp)
   int ti;
   /* Search through the trampoline for one that matches the
      instruction sequence around PC.  */
-  for (ti = 0; tramp->insn[ti] != 0; ti++)
+  for (ti = 0; tramp->insn[ti] != TRAMP_SENTINEL_INSN; ti++)
     {
       CORE_ADDR func = pc - tramp->insn_size * ti;
       int i;
       for (i = 0; 1; i++)
        {
-         bfd_byte buf[sizeof (LONGEST)];
-         CORE_ADDR insn;
-         if (tramp->insn[i] == 0)
+         bfd_byte buf[sizeof (tramp->insn[0])];
+         ULONGEST insn;
+         if (tramp->insn[i] == TRAMP_SENTINEL_INSN)
            return func;
          if (target_read_memory (func + i * tramp->insn_size, buf,
                                  tramp->insn_size) != 0)
@@ -148,6 +149,16 @@ tramp_frame_append (struct gdbarch *gdbarch,
 {
   struct frame_data *data;
   struct frame_unwind *unwinder;
+  int i;
+
+  /* Check that the instruction sequence contains a sentinel.  */
+  for (i = 0; i < ARRAY_SIZE (tramp_frame->insn); i++)
+    {
+      if (tramp_frame->insn[i] == TRAMP_SENTINEL_INSN)
+       break;
+    }
+  gdb_assert (i < ARRAY_SIZE (tramp_frame->insn));
+  gdb_assert (tramp_frame->insn_size <= sizeof (tramp_frame->insn[0]));
 
   data = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_data);
   unwinder = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind);

diff --git a/gdb/tramp-frame.h b/gdb/tramp-frame.h
index 44e266e..54f29bb 100644 (file)
--- a/gdb/tramp-frame.h
+++ b/gdb/tramp-frame.h
@@ -39,6 +39,10 @@ struct trad_frame_cache;
 
 /* A trampoline descriptor.  */
 
+/* Magic instruction that to mark the end of the signal trampoline
+   instruction sequence.  */
+#define TRAMP_SENTINEL_INSN ((LONGEST) -1)
+
 struct tramp_frame
 {
   /* The trampoline's entire instruction sequence.  Search for this in
@@ -47,7 +51,8 @@ struct tramp_frame
      one INSN_SIZE instruction.  It is also assumed that TRAMP[0]
      contains the first instruction of the trampoline and hence the
      address of the instruction matching TRAMP[0] is the trampoline's
-     "func" address.  */
+     "func" address.  The instruction sequence shall be terminated by
+     TRAMP_SENTINEL_INSN.  */
   int insn_size;
   ULONGEST insn[8];
   /* Initialize a trad-frame cache corresponding to the tramp-frame.