[6/7] remote: Consider byte size when reading/writing memory

Message ID 1428522979-28709-7-git-send-email-simon.marchi@ericsson.com
State New, archived
Headers

Commit Message

Simon Marchi April 8, 2015, 7:56 p.m. UTC
  Adapt code in remote.c to take into account memory byte size when
reading/writing memory.

A few variables are renamed and suffixed with _bytes or _octets. This
way, it's more obvious if there is any place where we add or compare
values in different units (which would be a mistake).

gdb/ChangeLog:

	* common/rsp-low.c (needs_escaping): New.
	(remote_escape_output): Add byte_size parameter and refactor to
	use it.  Rename parameters.
	* common/rsp-low.h (remote_escape_output): Add byte_size
	parameter and rename others. Update doc.
	* remote.c (align_for_efficient_write): New.
	(remote_write_bytes_aux): Add byte_size parameter and use it.
	Minor refactoring and variable renaming.
	(remote_xfer_partial): Get byte size and use it.
	(remote_read_bytes_1): Add byte_size parameter and use it.
	(remote_write_bytes): Same.
	(remote_xfer_live_readonly_partial): Same.
	(remote_read_bytes): Same.
	(remote_flash_write): Update call to remote_write_bytes_aux.
	(remote_write_qxfer): Update call to remote_escape_output.
	(remote_search_memory): Same.
	(remote_hostio_pwrite): Same.

gdb/gdbserver/ChangeLog:

	* server.c (write_qxfer_response): Update call to
	remote_escape_output.
---
 gdb/common/rsp-low.c   |  71 ++++++++++++++++-------
 gdb/common/rsp-low.h   |  16 +++---
 gdb/gdbserver/server.c |   4 +-
 gdb/remote.c           | 153 +++++++++++++++++++++++++++----------------------
 4 files changed, 145 insertions(+), 99 deletions(-)
  

Patch

diff --git a/gdb/common/rsp-low.c b/gdb/common/rsp-low.c
index d3d3d65..6e21208 100644
--- a/gdb/common/rsp-low.c
+++ b/gdb/common/rsp-low.c
@@ -146,38 +146,67 @@  bin2hex (const gdb_byte *bin, char *hex, int count)
   return i;
 }
 
+static int needs_escaping (gdb_byte b)
+{
+  return b == '$' || b == '#' || b == '}' || b == '*';
+}
+
 /* See rsp-low.h.  */
 
 int
-remote_escape_output (const gdb_byte *buffer, int len,
-		      gdb_byte *out_buf, int *out_len,
-		      int out_maxlen)
+remote_escape_output (const gdb_byte *buffer, int len_bytes, int byte_size,
+		      gdb_byte *out_buf, int *out_len_bytes,
+		      int out_maxlen_octets)
 {
-  int input_index, output_index;
-
-  output_index = 0;
-  for (input_index = 0; input_index < len; input_index++)
+  int input_byte_index, output_octet_index, octet_index_in_byte;
+
+  /* The number of octets we'll need to escape in that byte.  */
+  int number_escape_octets_needed;
+
+  /* Try to copy integral target memory bytes until
+     (1) we run out of space or
+     (2) we copied all of them.  */
+  output_octet_index = 0;
+  for (input_byte_index = 0;
+       input_byte_index < len_bytes;
+       input_byte_index++)
     {
-      gdb_byte b = buffer[input_index];
-
-      if (b == '$' || b == '#' || b == '}' || b == '*')
+      /* Find out how many escape octets we need for this byte.  */
+      number_escape_octets_needed = 0;
+      for (octet_index_in_byte = 0;
+	   octet_index_in_byte < byte_size;
+	   octet_index_in_byte++)
 	{
-	  /* These must be escaped.  */
-	  if (output_index + 2 > out_maxlen)
-	    break;
-	  out_buf[output_index++] = '}';
-	  out_buf[output_index++] = b ^ 0x20;
+	  int idx = input_byte_index * byte_size + octet_index_in_byte;
+	  gdb_byte b = buffer[idx];
+	  if (needs_escaping (b))
+	    number_escape_octets_needed++;
 	}
-      else
+
+      /* Check if we have room to fit this escaped byte.  */
+      if (output_octet_index + byte_size + number_escape_octets_needed >
+	    out_maxlen_octets)
+	  break;
+
+      /* Copy the byte octet per octet, adding escapes.  */
+      for (octet_index_in_byte = 0;
+	   octet_index_in_byte < byte_size;
+	   octet_index_in_byte++)
 	{
-	  if (output_index + 1 > out_maxlen)
-	    break;
-	  out_buf[output_index++] = b;
+	  int idx = input_byte_index * byte_size + octet_index_in_byte;
+	  gdb_byte b = buffer[idx];
+	  if (needs_escaping(b))
+	    {
+	      out_buf[output_octet_index++] = '}';
+	      out_buf[output_octet_index++] = b ^ 0x20;
+	    }
+	  else
+	    out_buf[output_octet_index++] = b;
 	}
     }
 
-  *out_len = input_index;
-  return output_index;
+  *out_len_bytes = input_byte_index;
+  return output_octet_index;
 }
 
 /* See rsp-low.h.  */
diff --git a/gdb/common/rsp-low.h b/gdb/common/rsp-low.h
index d62f67e..c20e88c 100644
--- a/gdb/common/rsp-low.h
+++ b/gdb/common/rsp-low.h
@@ -59,17 +59,17 @@  extern int hex2bin (const char *hex, gdb_byte *bin, int count);
 
 extern int bin2hex (const gdb_byte *bin, char *hex, int count);
 
-/* Convert BUFFER, binary data at least LEN bytes long, into escaped
-   binary data in OUT_BUF.  Set *OUT_LEN to the length of the data
-   encoded in OUT_BUF, and return the number of bytes in OUT_BUF
-   (which may be more than *OUT_LEN due to escape characters).  The
-   total number of bytes in the output buffer will be at most
+/* Convert BUFFER, binary data at least LEN_BYTES bytes long, into escaped
+   binary data in OUT_BUF.  Only copy target memory bytes that fit completely
+   in OUT_BUF.  Set *OUT_LEN_BYTES to the number of bytes from BUFFER
+   successfully encoded in OUT_BUF, and return the number of octets used in
+   OUT_BUF.  The total number of octets in the output buffer will be at most
    OUT_MAXLEN.  This function properly escapes '*', and so is suitable
    for the server side as well as the client.  */
 
-extern int remote_escape_output (const gdb_byte *buffer, int len,
-				 gdb_byte *out_buf, int *out_len,
-				 int out_maxlen);
+extern int remote_escape_output (const gdb_byte *buffer, int len_bytes,
+				 int byte_size, gdb_byte *out_buf,
+				 int *out_len_bytes, int out_maxlen_octets);
 
 /* Convert BUFFER, escaped data LEN bytes long, into binary data
    in OUT_BUF.  Return the number of bytes written to OUT_BUF.
diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c
index 3408ef7..367379e 100644
--- a/gdb/gdbserver/server.c
+++ b/gdb/gdbserver/server.c
@@ -383,8 +383,8 @@  write_qxfer_response (char *buf, const void *data, int len, int is_more)
   else
     buf[0] = 'l';
 
-  return remote_escape_output (data, len, (unsigned char *) buf + 1, &out_len,
-			       PBUFSIZ - 2) + 1;
+  return remote_escape_output (data, len, 1, (unsigned char *) buf + 1,
+			       &out_len, PBUFSIZ - 2) + 1;
 }
 
 /* Handle btrace enabling in BTS format.  */
diff --git a/gdb/remote.c b/gdb/remote.c
index dcd24c4..d9b4350 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -6639,6 +6639,16 @@  check_binary_download (CORE_ADDR addr)
     }
 }
 
+/* Helper function to resize the payload, in order to try to get a good
+   alignment.  We try to write an amount of data such that the next write will
+   start on an address aligned on REMOTE_ALIGN_WRITES.  */
+
+static int
+align_for_efficient_write (int todo_bytes, CORE_ADDR memaddr)
+{
+  return ((memaddr + todo_bytes) & ~(REMOTE_ALIGN_WRITES - 1)) - memaddr;
+}
+
 /* Write memory data directly to the remote machine.
    This does not inform the data cache; the data cache uses this.
    HEADER is the starting part of the packet.
@@ -6651,7 +6661,7 @@  check_binary_download (CORE_ADDR addr)
    The function creates packet of the form
        <HEADER><ADDRESS>,<LENGTH>:<DATA>
 
-   where encoding of <DATA> is termined by PACKET_FORMAT.
+   where encoding of <DATA> is terminated by PACKET_FORMAT.
 
    If USE_LENGTH is 0, then the <LENGTH> field and the preceding comma
    are omitted.
@@ -6662,28 +6672,27 @@  check_binary_download (CORE_ADDR addr)
 
 static enum target_xfer_status
 remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
-			const gdb_byte *myaddr, ULONGEST len,
-			ULONGEST *xfered_len, char packet_format,
+			const gdb_byte *myaddr, ULONGEST len_bytes,
+			int byte_size, ULONGEST *xfered_len_bytes, char packet_format,
 			int use_length)
 {
   struct remote_state *rs = get_remote_state ();
   char *p;
   char *plen = NULL;
   int plenlen = 0;
-  int todo;
-  int nr_bytes;
-  int payload_size;
-  int payload_length;
-  int header_length;
+  int todo_bytes;
+  int bytes_written;
+  int payload_capacity_octets;
+  int payload_length_octets;
 
   if (packet_format != 'X' && packet_format != 'M')
     internal_error (__FILE__, __LINE__,
 		    _("remote_write_bytes_aux: bad packet format"));
 
-  if (len == 0)
+  if (len_bytes == 0)
     return TARGET_XFER_EOF;
 
-  payload_size = get_memory_write_packet_size ();
+  payload_capacity_octets = get_memory_write_packet_size ();
 
   /* The packet buffer will be large enough for the payload;
      get_memory_packet_size ensures this.  */
@@ -6692,13 +6701,12 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
   /* Compute the size of the actual payload by subtracting out the
      packet header and footer overhead: "$M<memaddr>,<len>:...#nn".  */
 
-  payload_size -= strlen ("$,:#NN");
+  payload_capacity_octets -= strlen ("$,:#NN");
   if (!use_length)
     /* The comma won't be used.  */
-    payload_size += 1;
-  header_length = strlen (header);
-  payload_size -= header_length;
-  payload_size -= hexnumlen (memaddr);
+    payload_capacity_octets += 1;
+  payload_capacity_octets -= strlen (header);
+  payload_capacity_octets -= hexnumlen (memaddr);
 
   /* Construct the packet excluding the data: "<header><memaddr>,<len>:".  */
 
@@ -6709,28 +6717,29 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
   if (packet_format == 'X')
     {
       /* Best guess at number of bytes that will fit.  */
-      todo = min (len, payload_size);
+      todo_bytes = min (len_bytes, payload_capacity_octets / byte_size);
       if (use_length)
-	payload_size -= hexnumlen (todo);
-      todo = min (todo, payload_size);
+	/* The size in the packet is expressed in octets, not target bytes.  */
+	payload_capacity_octets -= hexnumlen (todo_bytes * byte_size);
+      todo_bytes = min (todo_bytes, payload_capacity_octets / byte_size);
     }
   else
     {
-      /* Num bytes that will fit.  */
-      todo = min (len, payload_size / 2);
+      /* Number of bytes that will fit.  */
+      todo_bytes = min (len_bytes, (payload_capacity_octets / byte_size) / 2);
       if (use_length)
-	payload_size -= hexnumlen (todo);
-      todo = min (todo, payload_size / 2);
+	payload_capacity_octets -= hexnumlen (todo_bytes * byte_size);
+      todo_bytes = min (todo_bytes, (payload_capacity_octets / byte_size) / 2);
     }
 
-  if (todo <= 0)
+  if (todo_bytes <= 0)
     internal_error (__FILE__, __LINE__,
 		    _("minimum packet size too small to write data"));
 
   /* If we already need another packet, then try to align the end
      of this packet to a useful boundary.  */
-  if (todo > 2 * REMOTE_ALIGN_WRITES && todo < len)
-    todo = ((memaddr + todo) & ~(REMOTE_ALIGN_WRITES - 1)) - memaddr;
+  if (todo_bytes > 2 * REMOTE_ALIGN_WRITES && todo_bytes < len_bytes)
+    todo_bytes = align_for_efficient_write (todo_bytes, memaddr);
 
   /* Append "<memaddr>".  */
   memaddr = remote_address_masked (memaddr);
@@ -6741,10 +6750,10 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
       /* Append ",".  */
       *p++ = ',';
 
-      /* Append <len>.  Retain the location/size of <len>.  It may need to
-	 be adjusted once the packet body has been created.  */
+      /* Append <len_bytes>.  Retain the location/size of the length.  It may
+         need to be adjusted once the packet body has been created.  */
       plen = p;
-      plenlen = hexnumstr (p, (ULONGEST) todo);
+      plenlen = hexnumstr (p, (ULONGEST) todo_bytes * byte_size);
       p += plenlen;
     }
 
@@ -6758,42 +6767,45 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
       /* Binary mode.  Send target system values byte by byte, in
 	 increasing byte addresses.  Only escape certain critical
 	 characters.  */
-      payload_length = remote_escape_output (myaddr, todo, (gdb_byte *) p,
-					     &nr_bytes, payload_size);
+      payload_length_octets =
+	  remote_escape_output (myaddr, todo_bytes, byte_size, (gdb_byte *) p,
+				&bytes_written, payload_capacity_octets);
 
       /* If not all TODO bytes fit, then we'll need another packet.  Make
 	 a second try to keep the end of the packet aligned.  Don't do
 	 this if the packet is tiny.  */
-      if (nr_bytes < todo && nr_bytes > 2 * REMOTE_ALIGN_WRITES)
+      if (bytes_written < todo_bytes && bytes_written > 2 * REMOTE_ALIGN_WRITES)
 	{
-	  int new_nr_bytes;
-
-	  new_nr_bytes = (((memaddr + nr_bytes) & ~(REMOTE_ALIGN_WRITES - 1))
-			  - memaddr);
-	  if (new_nr_bytes != nr_bytes)
-	    payload_length = remote_escape_output (myaddr, new_nr_bytes,
-						   (gdb_byte *) p, &nr_bytes,
-						   payload_size);
+	  int new_todo_bytes;
+
+	  new_todo_bytes = align_for_efficient_write (bytes_written, memaddr);
+
+	  if (new_todo_bytes != bytes_written)
+	    payload_length_octets =
+		remote_escape_output (myaddr, new_todo_bytes, byte_size,
+				      (gdb_byte *) p, &bytes_written,
+				      payload_capacity_octets);
 	}
 
-      p += payload_length;
-      if (use_length && nr_bytes < todo)
+      p += payload_length_octets;
+      if (use_length && bytes_written < todo_bytes)
 	{
 	  /* Escape chars have filled up the buffer prematurely,
 	     and we have actually sent fewer bytes than planned.
 	     Fix-up the length field of the packet.  Use the same
 	     number of characters as before.  */
-	  plen += hexnumnstr (plen, (ULONGEST) nr_bytes, plenlen);
+	  plen += hexnumnstr (plen, (ULONGEST) bytes_written * byte_size,
+			      plenlen);
 	  *plen = ':';  /* overwrite \0 from hexnumnstr() */
 	}
     }
   else
     {
       /* Normal mode: Send target system values byte by byte, in
-	 increasing byte addresses.  Each byte is encoded as a two hex
+	 increasing byte addresses.  Each octet is encoded as a two hex
 	 value.  */
-      nr_bytes = bin2hex (myaddr, p, todo);
-      p += 2 * nr_bytes;
+      p += 2 * bin2hex (myaddr, p, todo_bytes * byte_size);
+      bytes_written = todo_bytes;
     }
 
   putpkt_binary (rs->buf, (int) (p - rs->buf));
@@ -6804,7 +6816,7 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
 
   /* Return NR_BYTES, not TODO, in case escape chars caused us to send
      fewer bytes than we'd planned.  */
-  *xfered_len = (ULONGEST) nr_bytes;
+  *xfered_len_bytes = (ULONGEST) bytes_written;
   return TARGET_XFER_OK;
 }
 
@@ -6820,7 +6832,7 @@  remote_write_bytes_aux (const char *header, CORE_ADDR memaddr,
 
 static enum target_xfer_status
 remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, ULONGEST len,
-		    ULONGEST *xfered_len)
+		    int byte_size, ULONGEST *xfered_len)
 {
   char *packet_format = 0;
 
@@ -6843,7 +6855,7 @@  remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, ULONGEST len,
     }
 
   return remote_write_bytes_aux (packet_format,
-				 memaddr, myaddr, len, xfered_len,
+				 memaddr, myaddr, len, byte_size, xfered_len,
 				 packet_format[0], 1);
 }
 
@@ -6859,20 +6871,21 @@  remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, ULONGEST len,
 
 static enum target_xfer_status
 remote_read_bytes_1 (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
-		     ULONGEST *xfered_len)
+		     int byte_size, ULONGEST *xfered_len)
 {
   struct remote_state *rs = get_remote_state ();
   int max_buf_size;		/* Max size of packet output buffer.  */
   char *p;
-  int todo;
-  int i;
+  int todo_bytes;
+  int decoded_octets;
+  int len_octets = len * byte_size;
 
   max_buf_size = get_memory_read_packet_size ();
   /* The packet buffer will be large enough for the payload;
      get_memory_packet_size ensures this.  */
 
-  /* Number if bytes that will fit.  */
-  todo = min (len, max_buf_size / 2);
+  /* Number of bytes that will fit.  */
+  todo_bytes = min (len, (max_buf_size / byte_size) / 2);
 
   /* Construct "m"<memaddr>","<len>".  */
   memaddr = remote_address_masked (memaddr);
@@ -6880,7 +6893,7 @@  remote_read_bytes_1 (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
   *p++ = 'm';
   p += hexnumstr (p, (ULONGEST) memaddr);
   *p++ = ',';
-  p += hexnumstr (p, (ULONGEST) todo);
+  p += hexnumstr (p, (ULONGEST) todo_bytes * byte_size);
   *p = '\0';
   putpkt (rs->buf);
   getpkt (&rs->buf, &rs->buf_size, 0);
@@ -6891,9 +6904,9 @@  remote_read_bytes_1 (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
   /* Reply describes memory byte by byte, each byte encoded as two hex
      characters.  */
   p = rs->buf;
-  i = hex2bin (p, myaddr, todo);
+  decoded_octets = hex2bin (p, myaddr, todo_bytes * byte_size);
   /* Return what we have.  Let higher layers handle partial reads.  */
-  *xfered_len = (ULONGEST) i;
+  *xfered_len = (ULONGEST) (decoded_octets / byte_size);
   return TARGET_XFER_OK;
 }
 
@@ -6906,7 +6919,7 @@  remote_read_bytes_1 (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
 static enum target_xfer_status
 remote_xfer_live_readonly_partial (struct target_ops *ops, gdb_byte *readbuf,
 				   ULONGEST memaddr, ULONGEST len,
-				   ULONGEST *xfered_len)
+				   int byte_size, ULONGEST *xfered_len)
 {
   struct target_section *secp;
   struct target_section_table *table;
@@ -6929,7 +6942,7 @@  remote_xfer_live_readonly_partial (struct target_ops *ops, gdb_byte *readbuf,
 	      if (memend <= p->endaddr)
 		{
 		  /* Entire transfer is within this section.  */
-		  return remote_read_bytes_1 (memaddr, readbuf, len,
+		  return remote_read_bytes_1 (memaddr, readbuf, len, byte_size,
 					      xfered_len);
 		}
 	      else if (memaddr >= p->endaddr)
@@ -6941,7 +6954,7 @@  remote_xfer_live_readonly_partial (struct target_ops *ops, gdb_byte *readbuf,
 		{
 		  /* This section overlaps the transfer.  Just do half.  */
 		  len = p->endaddr - memaddr;
-		  return remote_read_bytes_1 (memaddr, readbuf, len,
+		  return remote_read_bytes_1 (memaddr, readbuf, len, byte_size,
 					      xfered_len);
 		}
 	    }
@@ -6957,7 +6970,8 @@  remote_xfer_live_readonly_partial (struct target_ops *ops, gdb_byte *readbuf,
 
 static enum target_xfer_status
 remote_read_bytes (struct target_ops *ops, CORE_ADDR memaddr,
-		   gdb_byte *myaddr, ULONGEST len, ULONGEST *xfered_len)
+		   gdb_byte *myaddr, ULONGEST len, int byte_size,
+		   ULONGEST *xfered_len)
 {
   if (len == 0)
     return TARGET_XFER_EOF;
@@ -6995,7 +7009,7 @@  remote_read_bytes (struct target_ops *ops, CORE_ADDR memaddr,
 
 	      /* This goes through the topmost target again.  */
 	      res = remote_xfer_live_readonly_partial (ops, myaddr, memaddr,
-						       len, xfered_len);
+						       len, byte_size, xfered_len);
 	      if (res == TARGET_XFER_OK)
 		return TARGET_XFER_OK;
 	      else
@@ -7017,7 +7031,7 @@  remote_read_bytes (struct target_ops *ops, CORE_ADDR memaddr,
 	}
     }
 
-  return remote_read_bytes_1 (memaddr, myaddr, len, xfered_len);
+  return remote_read_bytes_1 (memaddr, myaddr, len, byte_size, xfered_len);
 }
 
 
@@ -7103,7 +7117,7 @@  remote_flash_write (struct target_ops *ops, ULONGEST address,
 					  &saved_remote_timeout);
 
   remote_timeout = remote_flash_timeout;
-  ret = remote_write_bytes_aux ("vFlashWrite:", address, data, length,
+  ret = remote_write_bytes_aux ("vFlashWrite:", address, data, length, 1,
 				xfered_len,'X', 0);
   do_cleanups (back_to);
 
@@ -8775,7 +8789,7 @@  remote_write_qxfer (struct target_ops *ops, const char *object_name,
 
   /* Escape as much data as fits into rs->buf.  */
   buf_len = remote_escape_output 
-    (writebuf, len, (gdb_byte *) rs->buf + i, &max_size, max_size);
+    (writebuf, len, 1, (gdb_byte *) rs->buf + i, &max_size, max_size);
 
   if (putpkt_binary (rs->buf, i + buf_len) < 0
       || getpkt_sane (&rs->buf, &rs->buf_size, 0) < 0
@@ -8886,6 +8900,7 @@  remote_xfer_partial (struct target_ops *ops, enum target_object object,
   int i;
   char *p2;
   char query_type;
+  int byte_size = gdbarch_memory_byte_size (target_gdbarch ());
 
   set_remote_traceframe ();
   set_general_thread (inferior_ptid);
@@ -8902,9 +8917,11 @@  remote_xfer_partial (struct target_ops *ops, enum target_object object,
 	return TARGET_XFER_EOF;
 
       if (writebuf != NULL)
-	return remote_write_bytes (offset, writebuf, len, xfered_len);
+	return remote_write_bytes (offset, writebuf, len, byte_size,
+				   xfered_len);
       else
-	return remote_read_bytes (ops, offset, readbuf, len, xfered_len);
+	return remote_read_bytes (ops, offset, readbuf, len, byte_size,
+				  xfered_len);
     }
 
   /* Handle SPU memory using qxfer packets.  */
@@ -9137,7 +9154,7 @@  remote_search_memory (struct target_ops* ops,
 
   /* Escape as much data as fits into rs->buf.  */
   escaped_pattern_len =
-    remote_escape_output (pattern, pattern_len, (gdb_byte *) rs->buf + i,
+    remote_escape_output (pattern, pattern_len, 1, (gdb_byte *) rs->buf + i,
 			  &used_pattern_len, max_size);
 
   /* Bail if the pattern is too large.  */
@@ -9922,7 +9939,7 @@  remote_hostio_pwrite (struct target_ops *self,
   remote_buffer_add_int (&p, &left, offset);
   remote_buffer_add_string (&p, &left, ",");
 
-  p += remote_escape_output (write_buf, len, (gdb_byte *) p, &out_len,
+  p += remote_escape_output (write_buf, len, 1, (gdb_byte *) p, &out_len,
 			     get_remote_packet_size () - (p - rs->buf));
 
   return remote_hostio_send_command (p - rs->buf, PACKET_vFile_pwrite,