Re: [gdbserver/patch] Z packet support

[Orjan Friberg <orjan.friberg@axis.com>]

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Daniel Jacobowitz wrote:
> 
> You missed the most important problem with the previous posting, I'm
> afraid - it's still whitespace mangled.  Please don't send patches
> using format=flowed; it's very good for text, but lousy for data.
> Either disable it or just attach them.  I've more or less figured out
> the algorithm by which it ate your patch, but it's pretty tedious to
> hand-merge; could you resend?

Sure.  (Until I figure it out, I'll be attaching patches instead of inlining 
them.  Sorry for the trouble.)

> CORE_ADDR is always a long long in gdbserver, so your sizeof (addr)
> probably doesn't work right for 32-bit targets.  I guess sizeof (void
> *) is always right for this, though... at least for the kinds of
> targets gdbserver supports now.

FWIW, recurse.exp and watchpoints.exp ran fine on CRISv32 (32-bit target) when a 
64-bit address was sent.  I changed it nonetheless, and tweaked the comment.

-- 
Orjan Friberg
Axis Communications


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Index: target.h
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/target.h,v
retrieving revision 1.11
diff -u -p -r1.11 target.h
--- target.h	5 Mar 2004 03:43:19 -0000	1.11
+++ target.h	1 Feb 2005 12:02:58 -0000
@@ -133,6 +133,27 @@ struct target_ops
      Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 
   int (*read_auxv) (CORE_ADDR offset, char *myaddr, unsigned int len);
+
+  /* Insert and remove a hardware watchpoint.
+     Returns 0 on success, -1 on failure and 1 on unsupported.  
+     The type is coded as follows:
+       2 = write watchpoint
+       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);
+
+  /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise.  */
+
+  int (*stopped_by_watchpoint) (void);
+
+  /* Returns the address associated with the watchpoint that hit, if any;  
+     returns 0 otherwise.  */
+
+  CORE_ADDR (*stopped_data_address) (void);
+
 };
 
 extern struct target_ops *the_target;
Index: linux-low.h
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/linux-low.h,v
retrieving revision 1.7
diff -u -p -r1.7 linux-low.h
--- linux-low.h	31 Jan 2004 22:19:32 -0000	1.7
+++ linux-low.h	1 Feb 2005 12:02:58 -0000
@@ -57,6 +57,13 @@ 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);
+  int (*stopped_by_watchpoint) (void);
+  CORE_ADDR (*stopped_data_address) (void);
+
 };
 
 extern struct linux_target_ops the_low_target;
Index: linux-low.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/linux-low.c,v
retrieving revision 1.33
diff -u -p -r1.33 linux-low.c
--- linux-low.c	16 Oct 2004 17:42:00 -0000	1.33
+++ linux-low.c	1 Feb 2005 12:02:58 -0000
@@ -1466,7 +1466,47 @@ linux_read_auxv (CORE_ADDR offset, char 
   return n;
 }
 
-\f
+/* These 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)
+{
+  if (the_low_target.insert_watchpoint != NULL)
+    return the_low_target.insert_watchpoint (type, addr, len);
+  else
+    /* Unsupported (see target.h).  */
+    return 1;
+}
+
+static int
+linux_remove_watchpoint (char type, CORE_ADDR addr, int len)
+{
+  if (the_low_target.remove_watchpoint != NULL)
+    return the_low_target.remove_watchpoint (type, addr, len);
+  else
+    /* Unsupported (see target.h).  */
+    return 1;
+}
+
+static int
+linux_stopped_by_watchpoint (void)
+{
+  if (the_low_target.stopped_by_watchpoint != NULL)
+    return the_low_target.stopped_by_watchpoint ();
+  else
+    return 0;
+}
+
+static CORE_ADDR
+linux_stopped_data_address (void)
+{
+  if (the_low_target.stopped_data_address != NULL)
+    return the_low_target.stopped_data_address ();
+  else
+    return 0;
+}
+
 static struct target_ops linux_target_ops = {
   linux_create_inferior,
   linux_attach,
@@ -1482,6 +1522,10 @@ static struct target_ops linux_target_op
   linux_look_up_symbols,
   linux_send_signal,
   linux_read_auxv,
+  linux_insert_watchpoint,
+  linux_remove_watchpoint,
+  linux_stopped_by_watchpoint,
+  linux_stopped_data_address,
 };
 
 static void
Index: remote-utils.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/remote-utils.c,v
retrieving revision 1.22
diff -u -p -r1.22 remote-utils.c
--- remote-utils.c	16 Oct 2004 17:42:00 -0000	1.22
+++ remote-utils.c	1 Feb 2005 12:02:58 -0000
@@ -639,6 +639,28 @@ prepare_resume_reply (char *buf, char st
   if (status == 'T')
     {
       const char **regp = gdbserver_expedite_regs;
+
+      if (the_target->stopped_by_watchpoint != NULL
+	  && (*the_target->stopped_by_watchpoint) ())
+	{
+	  CORE_ADDR addr;
+	  int i;
+
+	  strncpy (buf, "watch:", 6);
+	  buf += 6;
+
+	  addr = (*the_target->stopped_data_address) ();
+
+	  /* Convert each byte of the address into two hexadecimal chars.
+	     Note that we take sizeof (void *) instead of sizeof (addr);
+	     this is to avoid sending a 64-bit address to a 32-bit GDB.  */
+	  for (i = sizeof (void *) * 2; i > 0; i--)
+	    {
+	      *buf++ = tohex ((addr >> (i - 1) * 4) & 0xf);
+	    }
+	  *buf++ = ';';
+	}
+
       while (*regp)
 	{
 	  buf = outreg (find_regno (*regp), buf);
Index: server.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/server.c,v
retrieving revision 1.22
diff -u -p -r1.22 server.c
--- server.c	5 Mar 2004 03:44:27 -0000	1.22
+++ server.c	1 Feb 2005 12:02:58 -0000
@@ -508,6 +508,66 @@ main (int argc, char *argv[])
 	      signal = mywait (&status, 1);
 	      prepare_resume_reply (own_buf, status, signal);
 	      break;
+	    case 'Z':
+	      {
+		char *lenptr;
+		char *dataptr;
+		CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16);
+		int len = strtol (lenptr + 1, &dataptr, 16);
+		char type = own_buf[1];
+
+		if (the_target->insert_watchpoint == NULL
+		    || (type < '2' || type > '4'))
+		  {
+		    /* No watchpoint support or not a watchpoint command;
+		       unrecognized either way.  */
+		    own_buf[0] = '\0';
+		  }
+		else
+		  {
+		    int res;
+
+		    res = (*the_target->insert_watchpoint) (type, addr, len);
+		    if (res == 0)
+		      write_ok (own_buf);
+		    else if (res == 1)
+		      /* Unsupported.  */
+		      own_buf[0] = '\0';
+		    else
+		      write_enn (own_buf);
+		  }
+		break;
+	      }
+	    case 'z':
+	      {
+		char *lenptr;
+		char *dataptr;
+		CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16);
+		int len = strtol (lenptr + 1, &dataptr, 16);
+		char type = own_buf[1];
+
+		if (the_target->remove_watchpoint == NULL
+		    || (type < '2' || type > '4'))
+		  {
+		    /* No watchpoint support or not a watchpoint command;
+		       unrecognized either way.  */
+		    own_buf[0] = '\0';
+		  }
+		else
+		  {
+		    int res;
+
+		    res = (*the_target->remove_watchpoint) (type, addr, len);
+		    if (res == 0)
+		      write_ok (own_buf);
+		    else if (res == 1)
+		      /* Unsupported.  */
+		      own_buf[0] = '\0';
+		    else
+		      write_enn (own_buf);
+		  }
+		break;
+	      }
 	    case 'k':
 	      fprintf (stderr, "Killing inferior\n");
 	      kill_inferior ();