Implement 'qXfer:exec-file:read' packet in Valgrind gdbserver.

Thanks to this packet, with recent GDB (>= 7.9.50.20150514-cvs), the
command 'target remote' will automatically load the executable file of
the process running under Valgrind. This means you do not need to
specify the executable file yourself, GDB will discover it itself.
See GDB documentation about 'qXfer:exec-file:read' packet for more
info.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15230

diff --git a/NEWS b/NEWS
index b702d0ade286e9430aa58e14dba0b59ae16bf646..40cf7ce75df4d53065b0b36cbb9a40cd53854062 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -48,6 +48,14 @@ Release 3.11.0 is under development, not yet released.
 * Valgrind can be built with Intel's ICC compiler. The required
   compiler version is 14.0 or later.
 
+* New and modified GDB server monitor features:
+
+  - With recent GDB (>= 7.9.50.20150514-cvs), the command 'target remote'
+    will automatically load the executable file of the process running
+    under Valgrind. This means you do not need to specify the executable
+    file yourself, GDB will discover it itself.
+    See GDB documentation about 'qXfer:exec-file:read' packet for more info.
+
 * ==================== FIXED BUGS ====================
 
 The following bugs have been fixed or resolved.  Note that "n-i-bz"

diff --git a/coregrind/m_gdbserver/server.c b/coregrind/m_gdbserver/server.c
index deedddf1180eec96fe64aeb82c748094e4ba16e5..6fb507ddc3e00ea27e686590ba2da1be51a20271 100644 (file)
--- a/coregrind/m_gdbserver/server.c
+++ b/coregrind/m_gdbserver/server.c
@@ -916,6 +916,63 @@ void handle_query (char *arg_own_buf, int *new_packet_len_p)
       return;
    }
 
+   if (strncmp ("qXfer:exec-file:read:", arg_own_buf, 21) == 0) {
+      unsigned char *data;
+      int n;
+      CORE_ADDR ofs;
+      unsigned int len;
+      const char *annex;
+      unsigned long pid;
+      const HChar *name;
+
+      /* Reject any annex; grab the offset and length.  */
+      if (decode_xfer_read (arg_own_buf + 21, &annex, &ofs, &len) < 0) {
+         strcpy (arg_own_buf, "E00");
+         return;
+      }
+      
+      if (strlen(annex) > 0)
+         pid = strtoul (annex, NULL, 16);
+      else
+         pid = 0;
+      if ((int)pid != VG_(getpid)() && pid != 0) {
+         VG_(sprintf) (arg_own_buf, 
+                       "E.Valgrind gdbserver pid is %d."
+                       " Cannot give info for pid %d",
+                       VG_(getpid)(), (int) pid);
+         return;
+      }
+
+      if (len > PBUFSIZ - 2)
+         len = PBUFSIZ - 2;
+      data = malloc (len);
+
+      if (!VG_(resolve_filename)(VG_(cl_exec_fd), &name)) {
+         VG_(sprintf) (arg_own_buf, 
+                       "E.Valgrind gdbserver could not"
+                       " resolve pid %d exec filename.",
+                       VG_(getpid)());
+         return;
+      }
+
+      if (ofs >= strlen(name))
+         n = -1;
+      else {
+         n = strlen(name) - ofs;
+         VG_(memcpy) (data, name, n);
+      }
+
+      if (n < 0)
+         write_enn (arg_own_buf);
+      else if (n > len)
+         *new_packet_len_p = write_qxfer_response (arg_own_buf, data, len, 1);
+      else
+         *new_packet_len_p = write_qxfer_response (arg_own_buf, data, n, 0);
+      
+      free (data);
+      
+      return;
+   }
 
    /* Protocol features query.  */
    if (strncmp ("qSupported", arg_own_buf, 10) == 0
@@ -923,7 +980,7 @@ void handle_query (char *arg_own_buf, int *new_packet_len_p)
       VG_(sprintf) (arg_own_buf, "PacketSize=%x", PBUFSIZ - 1);
       /* Note: max packet size including frame and checksum, but without
          trailing null byte, which is not sent/received. */
-      
+
       strcat (arg_own_buf, ";QStartNoAckMode+");
       strcat (arg_own_buf, ";QPassSignals+");
       if (VG_(client_auxv))
@@ -942,6 +999,7 @@ void handle_query (char *arg_own_buf, int *new_packet_len_p)
             not properly connect. */
          initialize_shadow_low(False);
       }
+      strcat (arg_own_buf, ";qXfer:exec-file:read+");
       return;
    }