2012-01-23  Yao Qi  <yao@codesourcery.com>

	* common/agent.c (struct ipa_sym_addresses) <addr_capability>: New.
	(agent_check_capability): New.
	(symbol_list): New array element.
	* common/agent.h (enum agent_capa): New.
---
 gdb/common/agent.c |   31 +++++++++++++++++++++++++++++++
 gdb/common/agent.h |   15 +++++++++++++++
 2 files changed, 46 insertions(+), 0 deletions(-)

diff --git a/gdb/common/agent.c b/gdb/common/agent.c
index 5c66071..f4ff08c 100644
--- a/gdb/common/agent.c
+++ b/gdb/common/agent.c
@@ -44,6 +44,7 @@ struct ipa_sym_addresses
 {
   CORE_ADDR addr_helper_thread_id;
   CORE_ADDR addr_cmd_buf;
+  CORE_ADDR addr_capability;
 };
 
 /* Cache of the helper thread id.  */
@@ -57,6 +58,7 @@ static struct
 } symbol_list[] = {
   IPA_SYM(helper_thread_id),
   IPA_SYM(cmd_buf),
+  IPA_SYM(capability),
 };
 
 static struct ipa_sym_addresses ipa_sym_addrs;
@@ -114,6 +116,9 @@ agent_get_helper_thread_id (void)
   return helper_thread_id;
 }
 
+/* Each bit of it stands for a capability of agent.  */
+static unsigned int agent_capability = 0;
+
 /* Connects to synchronization socket.  PID is the pid of inferior, which is
    used to set up connection socket.  */
 
@@ -260,3 +265,29 @@ agent_run_command (int pid, const char *cmd, int len)
 	}
     }
 }
+
+/* Return true if agent has capability AGENT_CAP, otherwise return false.  */
+
+int
+agent_check_capability (enum agent_capa agent_capa)
+{
+  if  (agent_capability == 0)
+    {
+#ifdef GDBSERVER
+      if (read_inferior_memory (ipa_sym_addrs.addr_capability,
+				(unsigned char *) &agent_capability,
+				sizeof agent_capability))
+#else
+      enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
+      gdb_byte buf[4];
+
+      if (target_read_memory (ipa_sym_addrs.addr_capability,
+			      buf, sizeof buf) == 0)
+	agent_capability = extract_unsigned_integer (buf, sizeof buf,
+						     byte_order);
+      else
+#endif
+	warning ("Error reading helper thread's id in lib");
+    }
+  return agent_capability & agent_capa;
+}
diff --git a/gdb/common/agent.h b/gdb/common/agent.h
index 079b65e..cf3fab1 100644
--- a/gdb/common/agent.h
+++ b/gdb/common/agent.h
@@ -36,3 +36,18 @@ void agent_look_up_symbols (void);
 extern int debug_agent ;
 
 extern int use_agent;
+
+/* Capability of agent.  Different agents may have different capabilities,
+   such as installing fast tracepoint or evaluating breakpoint conditions.
+   Capabilities are represented by bit-maps, and each capability occupy one
+   bit.  */
+
+enum agent_capa
+{
+  /* Capability to install fast tracepoint.  */
+  AGENT_CAPA_FAST_TRACE = 0x1,
+  /* Capability to install static tracepoint.  */
+  AGENT_CAPA_STATIC_TRACE = (0x1 << 1),
+};
+
+int agent_check_capability (enum agent_capa);
-- 
1.7.0.4