Re: [patch] gdbserver: Add support for Z0/Z1 packets

[Pedro Alves <pedro@codesourcery.com>]

On Wednesday 24 June 2009 19:50:44, Aleksandar Ristovski wrote:
> Pedro Alves wrote:
> > On Tuesday 23 June 2009 16:17:58, Aleksandar Ristovski wrote:
> >> Pedro Alves wrote:
> >>> On Monday 22 June 2009 20:38:50, Aleksandar Ristovski wrote:
> >>>
> >>>>> Z0 and Z1 breakpoints also take a 'len' argument, just
> >>>>> like Z2-Z4.  You should also pass those down.
> >>>>>
> >>>>> But, Let's take a step back --- why not just rename the
> >>>>> insert_watchpoint|remove_watchpoint functions to insert_point,remove_point,
> >>>>> and relax the type checks in server.c:
> > 
> >>>> But either way is fine with me - just let me know.
> >>> I'd prefer the approach I suggested, and worry about splitting
> >>> the breakpoints from watchpoints API if/when we actually need it.
> >>>
> >> Ok, then that version is committed.
> > 
> > Well, we had never seen "that" version
> 
> Ok, to rectify this I am attaching two versions: one if I 
> revert the changes I committed and the other is diff to what 
> is in now.
> 
>  > ... and you bypassed the "rename" suggestion...
> 
> I did not do any renaming - I think it is not terribly 
> confusing since both in target.h comment and server.c 'Z' 
> case it is made very clear that it handles both breakpoints 
> and watchpoints (i.e. I don't find it any clearer if it was 
> called "insert_point"... it would still require reading the 
> comment in target.h)


Urgh, I was just about to press the send button when I saw
this message of yours.  This version corrects a few troubles
with the previous commit (see ChangeLog) (one of them I still
see in your new patch) and I've tested it on x86_64-linux.
Aleksandar, please, please, do run the testsuite (and state
that you have) when posting patches.  E.g., we could have caught
the vKill issue that Pierre fixed when we made only linux
report multi-process (the testsuite runs in "target remote"
mode, hence with multi-process off most of the way).

-- 
Pedro Alves

2009-06-24  Pedro Alves  <pedro@codesourcery.com>

	* server.c (process_serial_event): Re-return unsupported, not
	error, if the type isn't recognized.  Re-allow supporting only
	insert or remove packets.  Also call require_running for
	breakpoints.  Add missing break statement to default case.  Tidy.
	* target.h (struct target_ops): Rename insert_watchpoint to
	insert_point, and remove_watchpoint to remove_point.

	* linux-low.h (struct linux_target_ops): Likewise.
	* linux-low.c (linux_insert_watchpoint): Rename to ...
	(linux_insert_point): ... this.  Adjust.
	(linux_remove_watchpoint): Rename to ...
	(linux_remove_point): ... this.  Adjust.
	(linux_target_ops): Adjust.
	* linux-crisv32-low.c (cris_insert_watchpoint): Rename to ...
	(cris_insert_point): ... this.
	(cris_remove_watchpoint): Rename to ...
	(cris_remove_point): ... this.
	(the_low_target): Adjust.

---
 gdb/gdbserver/linux-crisv32-low.c |    8 +++---
 gdb/gdbserver/linux-low.c         |   21 ++++++++-------
 gdb/gdbserver/linux-low.h         |    7 +++--
 gdb/gdbserver/server.c            |   50 ++++++++++++++------------------------
 gdb/gdbserver/target.h            |    6 ++--
 5 files changed, 41 insertions(+), 51 deletions(-)

Index: src/gdb/gdbserver/server.c
===================================================================
--- src.orig/gdb/gdbserver/server.c	2009-06-24 19:48:36.000000000 +0100
+++ src/gdb/gdbserver/server.c	2009-06-24 19:58:34.000000000 +0100
@@ -2383,38 +2383,26 @@ process_serial_event (void)
 	int len = strtol (lenptr + 1, &dataptr, 16);
 	char type = own_buf[1];
 	int res;
-	const int insert_ = ch == 'Z';
+	const int insert = ch == 'Z';
 
-	/* Type: '0' - software-breakpoint
-		 '1' - hardware-breakpoint
-		 '2' - write watchpoint
-		 '3' - read watchpoint
-		 '4' - access watchpoint  */
-
-	if (the_target->insert_watchpoint == NULL
-	    || the_target->remove_watchpoint == NULL)
-	  res = 1;  /* Not supported.  */
-	else
-	  switch (type)
-	    {
-	    case '2':
-	      /* Fallthrough.  */
-	    case '3':
-	      /* Fallthrough.  */
-	    case '4':
-	      require_running (own_buf);
-	      /* Fallthrough.  */
-	    case '0':
-	      /* Fallthrough.  */
-	    case '1':
-	      res = insert_ ? (*the_target->insert_watchpoint) (type, addr,
-								len)
-			    : (*the_target->remove_watchpoint) (type, addr,
-								len);
-	      break;
-	    default:
-	      res = -1; /* Unrecognized type.  */
-	    }
+	/* Default to unrecognized/unsupported.  */
+	res = 1;
+	switch (type)
+	  {
+	  case '0': /* software-breakpoint */
+	  case '1': /* hardware-breakpoint */
+	  case '2': /* write watchpoint */
+	  case '3': /* read watchpoint */
+	  case '4': /* access watchpoint */
+	    require_running (own_buf);
+	    if (insert && the_target->insert_point != NULL)
+	      res = (*the_target->insert_point) (type, addr, len);
+	    else if (!insert && the_target->remove_point != NULL)
+	      res = (*the_target->remove_point) (type, addr, len);
+	    break;
+	  default:
+	    break;
+	  }
 
 	if (res == 0)
 	  write_ok (own_buf);
Index: src/gdb/gdbserver/target.h
===================================================================
--- src.orig/gdb/gdbserver/target.h	2009-06-24 19:48:36.000000000 +0100
+++ src/gdb/gdbserver/target.h	2009-06-24 19:48:37.000000000 +0100
@@ -213,7 +213,7 @@ struct target_ops
   int (*read_auxv) (CORE_ADDR offset, unsigned char *myaddr,
 		    unsigned int len);
 
-  /* Insert and remove a hardware watchpoint.
+  /* Insert and remove a break or watchpoint.
      Returns 0 on success, -1 on failure and 1 on unsupported.
      The type is coded as follows:
        '0' - software-breakpoint
@@ -222,8 +222,8 @@ struct target_ops
        '3' - read watchpoint
        '4' - access watchpoint  */
 
-  int (*insert_watchpoint) (char type, CORE_ADDR addr, int len);
-  int (*remove_watchpoint) (char type, CORE_ADDR addr, int len);
+  int (*insert_point) (char type, CORE_ADDR addr, int len);
+  int (*remove_point) (char type, CORE_ADDR addr, int len);
 
   /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise.  */
 
Index: src/gdb/gdbserver/linux-low.h
===================================================================
--- src.orig/gdb/gdbserver/linux-low.h	2009-06-24 19:48:36.000000000 +0100
+++ src/gdb/gdbserver/linux-low.h	2009-06-24 19:48:37.000000000 +0100
@@ -80,9 +80,10 @@ struct linux_target_ops
   int decr_pc_after_break;
   int (*breakpoint_at) (CORE_ADDR pc);
 
-  /* Watchpoint related functions.  See target.h for comments.  */
-  int (*insert_watchpoint) (char type, CORE_ADDR addr, int len);
-  int (*remove_watchpoint) (char type, CORE_ADDR addr, int len);
+  /* Breakpoint and watchpoint related functions.  See target.h for
+     comments.  */
+  int (*insert_point) (char type, CORE_ADDR addr, int len);
+  int (*remove_point) (char type, CORE_ADDR addr, int len);
   int (*stopped_by_watchpoint) (void);
   CORE_ADDR (*stopped_data_address) (void);
 
Index: src/gdb/gdbserver/linux-low.c
===================================================================
--- src.orig/gdb/gdbserver/linux-low.c	2009-06-24 19:48:36.000000000 +0100
+++ src/gdb/gdbserver/linux-low.c	2009-06-24 19:48:37.000000000 +0100
@@ -2671,24 +2671,25 @@ linux_read_auxv (CORE_ADDR offset, unsig
   return n;
 }
 
-/* These watchpoint related wrapper functions simply pass on the function call
-   if the target has registered a corresponding function.  */
+/* These breakpoint and watchpoint related wrapper functions simply
+   pass on the function call if the target has registered a
+   corresponding function.  */
 
 static int
-linux_insert_watchpoint (char type, CORE_ADDR addr, int len)
+linux_insert_point (char type, CORE_ADDR addr, int len)
 {
-  if (the_low_target.insert_watchpoint != NULL)
-    return the_low_target.insert_watchpoint (type, addr, len);
+  if (the_low_target.insert_point != NULL)
+    return the_low_target.insert_point (type, addr, len);
   else
     /* Unsupported (see target.h).  */
     return 1;
 }
 
 static int
-linux_remove_watchpoint (char type, CORE_ADDR addr, int len)
+linux_remove_point (char type, CORE_ADDR addr, int len)
 {
-  if (the_low_target.remove_watchpoint != NULL)
-    return the_low_target.remove_watchpoint (type, addr, len);
+  if (the_low_target.remove_point != NULL)
+    return the_low_target.remove_point (type, addr, len);
   else
     /* Unsupported (see target.h).  */
     return 1;
@@ -3030,8 +3031,8 @@ static struct target_ops linux_target_op
   linux_look_up_symbols,
   linux_request_interrupt,
   linux_read_auxv,
-  linux_insert_watchpoint,
-  linux_remove_watchpoint,
+  linux_insert_point,
+  linux_remove_point,
   linux_stopped_by_watchpoint,
   linux_stopped_data_address,
 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
Index: src/gdb/gdbserver/linux-crisv32-low.c
===================================================================
--- src.orig/gdb/gdbserver/linux-crisv32-low.c	2009-06-24 19:48:35.000000000 +0100
+++ src/gdb/gdbserver/linux-crisv32-low.c	2009-06-24 19:48:37.000000000 +0100
@@ -137,7 +137,7 @@ cris_write_data_breakpoint (int bp, unsi
 }
 
 static int
-cris_insert_watchpoint (char type, CORE_ADDR addr, int len)
+cris_insert_point (char type, CORE_ADDR addr, int len)
 {
   int bp;
   unsigned long bp_ctrl;
@@ -220,7 +220,7 @@ cris_insert_watchpoint (char type, CORE_
 }
 
 static int
-cris_remove_watchpoint (char type, CORE_ADDR addr, int len)
+cris_remove_point (char type, CORE_ADDR addr, int len)
 {
   int bp;
   unsigned long bp_ctrl;
@@ -375,8 +375,8 @@ struct linux_target_ops the_low_target =
   cris_reinsert_addr,
   0,
   cris_breakpoint_at,
-  cris_insert_watchpoint,
-  cris_remove_watchpoint,
+  cris_insert_point,
+  cris_remove_point,
   cris_stopped_by_watchpoint,
   cris_stopped_data_address,
 };