[commit] Remove an excess memcpy in remote.c

[Daniel Jacobowitz <drow at false dot org>]

This memcpy has been there for years, because remote_xfer_memory took a
non-const argument.  I added it, although I think I copied it from
elsewhere.  There's not really any disadvantage to casting the const
writebuf to non-const for this purpose, since we know it won't be modified,
but anyway we can do it right now; call remote_write_bytes directly.

In the process it fixes a theoretical buglet on platforms which use both
fileio and the dubious gdbarch_remote_translate_xfer_address hook.

Tested and committed.

-- 
Daniel Jacobowitz
CodeSourcery

2006-08-15  Daniel Jacobowitz  <dan@codesourcery.com>

	* remote.c (remote_write_bytes): Take a const buffer argument.
	Do the checks from remote_xfer_memory.
	(remote_read_bytes): Do the checks from remote_xfer_memory.
	(remote_xfer_memory): Remove checks pushed into lower level
	functions.
	(remote_xfer_partial): Call remote_write_bytes and remote_read_bytes
	directly.
	* remote.h (remote_write_bytes): Update prototype.

---
 gdb/remote.c |   46 ++++++++++++++++++++++++----------------------
 gdb/remote.h |    3 ++-
 2 files changed, 26 insertions(+), 23 deletions(-)

Index: src/gdb/remote.c
===================================================================
--- src.orig/gdb/remote.c	2006-08-10 23:21:52.000000000 -0400
+++ src/gdb/remote.c	2006-08-11 10:31:58.000000000 -0400
@@ -3853,7 +3853,7 @@ check_binary_download (CORE_ADDR addr)
    error.  Only transfer a single packet.  */
 
 int
-remote_write_bytes (CORE_ADDR memaddr, gdb_byte *myaddr, int len)
+remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, int len)
 {
   struct remote_state *rs = get_remote_state ();
   char *buf;
@@ -3865,6 +3865,15 @@ remote_write_bytes (CORE_ADDR memaddr, g
   int payload_size;
   int payload_length;
 
+  /* Should this be the selected frame?  */
+  gdbarch_remote_translate_xfer_address (current_gdbarch,
+					 current_regcache,
+					 memaddr, len,
+					 &memaddr, &len);
+
+  if (len <= 0)
+    return 0;
+
   /* Verify that the target can support a binary download.  */
   check_binary_download (memaddr);
 
@@ -4023,6 +4032,15 @@ remote_read_bytes (CORE_ADDR memaddr, gd
   int max_buf_size;		/* Max size of packet output buffer.  */
   int origlen;
 
+  /* Should this be the selected frame?  */
+  gdbarch_remote_translate_xfer_address (current_gdbarch,
+					 current_regcache,
+					 memaddr, len,
+					 &memaddr, &len);
+
+  if (len <= 0)
+    return 0;
+
   max_buf_size = get_memory_read_packet_size ();
   /* The packet buffer will be large enough for the payload;
      get_memory_packet_size ensures this.  */
@@ -4090,22 +4108,12 @@ remote_xfer_memory (CORE_ADDR mem_addr, 
 		    int should_write, struct mem_attrib *attrib,
 		    struct target_ops *target)
 {
-  CORE_ADDR targ_addr;
-  int targ_len;
   int res;
 
-  /* Should this be the selected frame?  */
-  gdbarch_remote_translate_xfer_address (current_gdbarch, 
-					 current_regcache,
-					 mem_addr, mem_len,
-					 &targ_addr, &targ_len);
-  if (targ_len <= 0)
-    return 0;
-
   if (should_write)
-    res = remote_write_bytes (targ_addr, buffer, targ_len);
+    res = remote_write_bytes (mem_addr, buffer, mem_len);
   else
-    res = remote_read_bytes (targ_addr, buffer, targ_len);
+    res = remote_read_bytes (mem_addr, buffer, mem_len);
 
   return res;
 }
@@ -5270,22 +5278,16 @@ remote_xfer_partial (struct target_ops *
   char *p2;
   char query_type;
 
-  /* Handle memory using remote_xfer_memory.  */
+  /* Handle memory using the standard memory routines.  */
   if (object == TARGET_OBJECT_MEMORY)
     {
       int xfered;
       errno = 0;
 
       if (writebuf != NULL)
-	{
-	  void *buffer = xmalloc (len);
-	  struct cleanup *cleanup = make_cleanup (xfree, buffer);
-	  memcpy (buffer, writebuf, len);
-	  xfered = remote_xfer_memory (offset, buffer, len, 1, NULL, ops);
-	  do_cleanups (cleanup);
-	}
+	xfered = remote_write_bytes (offset, writebuf, len);
       else
-	xfered = remote_xfer_memory (offset, readbuf, len, 0, NULL, ops);
+	xfered = remote_read_bytes (offset, readbuf, len);
 
       if (xfered > 0)
 	return xfered;
Index: src/gdb/remote.h
===================================================================
--- src.orig/gdb/remote.h	2006-08-10 23:23:47.000000000 -0400
+++ src/gdb/remote.h	2006-08-10 23:23:54.000000000 -0400
@@ -55,7 +55,8 @@ extern void remote_cisco_objfile_relocat
 
 extern void async_remote_interrupt_twice (void *arg);
 
-extern int remote_write_bytes (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
+extern int remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr,
+			       int len);
 
 extern int remote_read_bytes (CORE_ADDR memaddr, gdb_byte *myaddr, int len);