Re: [patch/rfc] Implement ptrace target vector inheritance

[Andrew Cagney <cagney at gnu dot org>]

> Hello,
>
> This came from an thread between myself and MarkK (I can't find the url).
>
> The current native code constructs its target vector using a convoluted combination of #ifdefs and global functions.
>
> This patch replaces all that with what is effectively a runtime inheritance structure:
>
>     inf-ptrace is-a inf-child is-a target
>
> I've updated/tested NetBSD/PPC, with a tweak to nbsdppc-nat. that further extends the above with:
>
>     nbsdppc-nat is-a inf-ptrace
>
> there were no regressions.
>
> The intent is for all natives to eventually migrate to this.
>
> Comments?
>
> Right now I'm more interested in high-level stuff - the idea and the strategy.  I'm sure the implementation will evolve as more natives come on board, and as I eliminate a few remaining globals.
>
> I'll leave this for a week,

I've checked in the attached, per suggestions.  I've left out the new 
commands (keeping new functionality separate from refactoring).  I've 
also left a few things like call_ptrace in infptrace.c.

committed,
Andrew

2004-09-12  Andrew Cagney  <cagney@gnu.org>

	* ppcnbsd-nat.c: Include "inf-ptrace.h".
	(ppcnbsd_fetch_inferior_registers): Rename fetch_inferior_registers.
	(ppcnbsd_store_inferior_registers): Rename store_inferior_registers.
	(_initialize_ppcnbsd_nat): Create and add a NetBSD/PPC ptrace
	target.
	* config/powerpc/nbsd.mh (NATDEPFILES): Replace and inftarg.o with
	inf-ptrace.o and inf-child.o.
	* inf-ptrace.h, inf-ptrace.c, inf-child.h, inf-child.c: New files.
	* Makefile.in: Update dependencies.
	
Index: ppcnbsd-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/ppcnbsd-nat.c,v
retrieving revision 1.17
diff -p -u -r1.17 ppcnbsd-nat.c
--- ppcnbsd-nat.c	14 Aug 2004 23:37:04 -0000	1.17
+++ ppcnbsd-nat.c	11 Sep 2004 15:08:44 -0000
@@ -35,6 +35,8 @@
 #include "ppc-tdep.h"
 #include "ppcnbsd-tdep.h"
 
+#include "inf-ptrace.h"
+
 /* Returns true if PT_GETREGS fetches this register.  */
 static int
 getregs_supplies (int regno)
@@ -73,8 +75,8 @@ getfpregs_supplies (int regno)
 	  || regno == tdep->ppc_fpscr_regnum);
 }
 
-void
-fetch_inferior_registers (int regno)
+static void
+ppcnbsd_fetch_inferior_registers (int regno)
 {
   if (regno == -1 || getregs_supplies (regno))
     {
@@ -103,8 +105,8 @@ fetch_inferior_registers (int regno)
     }
 }
 
-void
-store_inferior_registers (int regno)
+static void
+ppcnbsd_store_inferior_registers (int regno)
 {
   if (regno == -1 || getregs_supplies (regno))
     {
@@ -177,6 +179,12 @@ void _initialize_ppcnbsd_nat (void);
 void
 _initialize_ppcnbsd_nat (void)
 {
+  struct target_ops *t;
   /* Support debugging kernel virtual memory images.  */
   bsd_kvm_add_target (ppcnbsd_supply_pcb);
+  /* Add in local overrides.  */
+  t = inf_ptrace_target ();
+  t->to_fetch_registers = ppcnbsd_fetch_inferior_registers;
+  t->to_store_registers = ppcnbsd_store_inferior_registers;
+  add_target (t);
 }
Index: config/powerpc/nbsd.mh
===================================================================
RCS file: /cvs/src/src/gdb/config/powerpc/nbsd.mh,v
retrieving revision 1.13
diff -p -u -r1.13 nbsd.mh
--- config/powerpc/nbsd.mh	3 Sep 2004 19:08:20 -0000	1.13
+++ config/powerpc/nbsd.mh	11 Sep 2004 15:08:44 -0000
@@ -1,5 +1,5 @@
 # Host: PowerPC, running NetBSD
-NATDEPFILES= fork-child.o infptrace.o inftarg.o ppcnbsd-nat.o bsd-kvm.o
+NATDEPFILES= fork-child.o inf-child.o inf-ptrace.o infptrace.o ppcnbsd-nat.o bsd-kvm.o
 NAT_FILE= config/nm-nbsd.h
 
 LOADLIBES= -lkvm