Added batch GRPC_TRACE option to trace calls to grpc_call_start_batch
diff --git a/Makefile b/Makefile
index 8c6fc32..242ce79 100644
--- a/Makefile
+++ b/Makefile
@@ -2436,6 +2436,7 @@
     src/core/surface/byte_buffer_reader.c \
     src/core/surface/call.c \
     src/core/surface/call_details.c \
+    src/core/surface/call_log_batch.c \
     src/core/surface/channel.c \
     src/core/surface/channel_create.c \
     src/core/surface/client.c \
@@ -2581,6 +2582,7 @@
 src/core/surface/byte_buffer_reader.c: $(OPENSSL_DEP)
 src/core/surface/call.c: $(OPENSSL_DEP)
 src/core/surface/call_details.c: $(OPENSSL_DEP)
+src/core/surface/call_log_batch.c: $(OPENSSL_DEP)
 src/core/surface/channel.c: $(OPENSSL_DEP)
 src/core/surface/channel_create.c: $(OPENSSL_DEP)
 src/core/surface/client.c: $(OPENSSL_DEP)
@@ -2743,6 +2745,7 @@
 $(OBJDIR)/$(CONFIG)/src/core/surface/byte_buffer_reader.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/call.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/call_details.o: 
+$(OBJDIR)/$(CONFIG)/src/core/surface/call_log_batch.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/channel.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/channel_create.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/client.o: 
@@ -2918,6 +2921,7 @@
     src/core/surface/byte_buffer_reader.c \
     src/core/surface/call.c \
     src/core/surface/call_details.c \
+    src/core/surface/call_log_batch.c \
     src/core/surface/channel.c \
     src/core/surface/channel_create.c \
     src/core/surface/client.c \
@@ -3056,6 +3060,7 @@
 $(OBJDIR)/$(CONFIG)/src/core/surface/byte_buffer_reader.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/call.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/call_details.o: 
+$(OBJDIR)/$(CONFIG)/src/core/surface/call_log_batch.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/channel.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/channel_create.o: 
 $(OBJDIR)/$(CONFIG)/src/core/surface/client.o: 
diff --git a/build.json b/build.json
index c9500eb..6650801 100644
--- a/build.json
+++ b/build.json
@@ -224,6 +224,7 @@
         "src/core/surface/byte_buffer_reader.c",
         "src/core/surface/call.c",
         "src/core/surface/call_details.c",
+        "src/core/surface/call_log_batch.c",
         "src/core/surface/channel.c",
         "src/core/surface/channel_create.c",
         "src/core/surface/client.c",
diff --git a/src/core/surface/call.c b/src/core/surface/call.c
index cfce943..dba6305 100644
--- a/src/core/surface/call.c
+++ b/src/core/surface/call.c
@@ -1006,6 +1006,8 @@
   const grpc_op *op;
   grpc_ioreq *req;
 
+  GRPC_CALL_LOG_BATCH(GPR_INFO, call, ops, nops, tag);
+
   if (nops == 0) {
     grpc_cq_begin_op(call->cq, call, GRPC_OP_COMPLETE);
     grpc_cq_end_op_complete(call->cq, tag, call, do_nothing, NULL, GRPC_OP_OK);
diff --git a/src/core/surface/call.h b/src/core/surface/call.h
index cb81cb5..06434f8 100644
--- a/src/core/surface/call.h
+++ b/src/core/surface/call.h
@@ -119,4 +119,13 @@
 /* Given the top call_element, get the call object. */
 grpc_call *grpc_call_from_top_element(grpc_call_element *surface_element);
 
+extern int grpc_trace_batch;
+
+void grpc_call_log_batch(char *file, int line, gpr_log_severity severity,
+                         grpc_call *call, const grpc_op *ops, size_t nops,
+                         void *tag);
+
+#define GRPC_CALL_LOG_BATCH(sev, call, ops, nops, tag) \
+  if (grpc_trace_batch) grpc_call_log_batch(sev, call, ops, nops, tag)
+
 #endif  /* GRPC_INTERNAL_CORE_SURFACE_CALL_H */
diff --git a/src/core/surface/call_log_batch.c b/src/core/surface/call_log_batch.c
new file mode 100644
index 0000000..482957d
--- /dev/null
+++ b/src/core/surface/call_log_batch.c
@@ -0,0 +1,121 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/surface/call.h"
+
+#include "src/core/support/string.h"
+#include <grpc/support/alloc.h>
+
+int grpc_trace_batch = 0;
+
+static void add_metadata(gpr_strvec *b, const grpc_metadata *md, size_t count) {
+  size_t i;
+  for(i = 0; i < count; i++) {
+    gpr_strvec_add(b, gpr_strdup("\nkey="));
+    gpr_strvec_add(b, gpr_strdup(md[i].key));
+
+    gpr_strvec_add(b, gpr_strdup(" value="));
+    gpr_strvec_add(b, gpr_hexdump(md[i].value, md[i].value_length,
+                                  GPR_HEXDUMP_PLAINTEXT));
+  }
+}
+
+char *grpc_op_string(const grpc_op *op) {
+  char *tmp;
+  char *out;
+
+  gpr_strvec b;
+  gpr_strvec_init(&b);
+
+  switch (op->op) {
+    case GRPC_OP_SEND_INITIAL_METADATA:
+      gpr_strvec_add(&b, gpr_strdup("SEND_INITIAL_METADATA"));
+      add_metadata(&b, op->data.send_initial_metadata.metadata,
+                   op->data.send_initial_metadata.count);
+      break;
+    case GRPC_OP_SEND_MESSAGE:
+      gpr_asprintf(&tmp, "SEND_MESSAGE ptr=%p", op->data.send_message);
+      gpr_strvec_add(&b, tmp);
+      break;
+    case GRPC_OP_SEND_CLOSE_FROM_CLIENT:
+      gpr_strvec_add(&b, gpr_strdup("SEND_CLOSE_FROM_CLIENT"));
+      break;
+    case GRPC_OP_SEND_STATUS_FROM_SERVER:
+      gpr_asprintf(&tmp, "SEND_STATUS_FROM_SERVER status=%d details=%s",
+                   op->data.send_status_from_server.status,
+                   op->data.send_status_from_server.status_details);
+      gpr_strvec_add(&b, tmp);
+      add_metadata(&b, op->data.send_status_from_server.trailing_metadata,
+                   op->data.send_status_from_server.trailing_metadata_count);
+      break;
+    case GRPC_OP_RECV_INITIAL_METADATA:
+      gpr_asprintf(&tmp, "RECV_INITIAL_METADATA ptr=%p",
+                   op->data.recv_initial_metadata);
+      gpr_strvec_add(&b, tmp);
+      break;
+    case GRPC_OP_RECV_MESSAGE:
+      gpr_asprintf(&tmp, "RECV_MESSAGE ptr=%p", op->data.recv_message);
+      gpr_strvec_add(&b, tmp);
+      break;
+    case GRPC_OP_RECV_STATUS_ON_CLIENT:
+      gpr_asprintf(&tmp,
+                   "RECV_STATUS_ON_CLIENT metadata=%p status=%p details=%p",
+                   op->data.recv_status_on_client.trailing_metadata,
+                   op->data.recv_status_on_client.status,
+                   op->data.recv_status_on_client.status_details);
+      gpr_strvec_add(&b, tmp);
+      break;
+    case GRPC_OP_RECV_CLOSE_ON_SERVER:
+      gpr_asprintf(&tmp, "RECV_CLOSE_ON_SERVER cancelled=%p",
+                   op->data.recv_close_on_server.cancelled);
+      gpr_strvec_add(&b, tmp);
+  }
+  out = gpr_strvec_flatten(&b, NULL);
+  gpr_strvec_destroy(&b);
+
+  return out;
+}
+
+void grpc_call_log_batch(char *file, int line, gpr_log_severity severity,
+                         grpc_call *call, const grpc_op *ops, size_t nops,
+                         void *tag) {
+  char *tmp;
+  size_t i;
+  gpr_log(file, line, severity,
+          "grpc_call_start_batch(%p, %p, %d, 0x%x)", call, ops, nops);
+  for(i = 0; i < nops; i++) {
+    tmp = grpc_op_string(&ops[i]);
+    gpr_log(file, line, severity, "ops[%d]: %s", i, tmp);
+    gpr_free(tmp);
+  }
+}
diff --git a/src/core/surface/init.c b/src/core/surface/init.c
index e48c420..d4f0eb4 100644
--- a/src/core/surface/init.c
+++ b/src/core/surface/init.c
@@ -36,6 +36,7 @@
 #include "src/core/debug/trace.h"
 #include "src/core/statistics/census_interface.h"
 #include "src/core/channel/channel_stack.h"
+#include "src/core/surface/call.h"
 #include "src/core/surface/init.h"
 #include "src/core/surface/surface_trace.h"
 #include "src/core/transport/chttp2_transport.h"
@@ -57,6 +58,7 @@
     grpc_register_tracer("channel", &grpc_trace_channel);
     grpc_register_tracer("surface", &grpc_surface_trace);
     grpc_register_tracer("http", &grpc_http_trace);
+    grpc_register_tracer("batch", &grpc_trace_batch);
     grpc_security_pre_init();
     grpc_tracer_init("GRPC_TRACE");
     grpc_iomgr_init();
@@ -82,4 +84,3 @@
   gpr_mu_unlock(&g_init_mu);
   return r;
 }
-
diff --git a/vsprojects/vs2013/grpc.vcxproj b/vsprojects/vs2013/grpc.vcxproj
index 9d0bcb3..d5079d6 100644
--- a/vsprojects/vs2013/grpc.vcxproj
+++ b/vsprojects/vs2013/grpc.vcxproj
@@ -355,6 +355,8 @@
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\call_details.c">
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel_create.c">
diff --git a/vsprojects/vs2013/grpc.vcxproj.filters b/vsprojects/vs2013/grpc.vcxproj.filters
index af38d8d..bb91b71 100644
--- a/vsprojects/vs2013/grpc.vcxproj.filters
+++ b/vsprojects/vs2013/grpc.vcxproj.filters
@@ -253,6 +253,9 @@
     <ClCompile Include="..\..\src\core\surface\call_details.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+      <Filter>src\core\surface</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>
diff --git a/vsprojects/vs2013/grpc_shared.vcxproj b/vsprojects/vs2013/grpc_shared.vcxproj
index f5575dc..f81539e 100644
--- a/vsprojects/vs2013/grpc_shared.vcxproj
+++ b/vsprojects/vs2013/grpc_shared.vcxproj
@@ -359,6 +359,8 @@
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\call_details.c">
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel_create.c">
diff --git a/vsprojects/vs2013/grpc_shared.vcxproj.filters b/vsprojects/vs2013/grpc_shared.vcxproj.filters
index af38d8d..bb91b71 100644
--- a/vsprojects/vs2013/grpc_shared.vcxproj.filters
+++ b/vsprojects/vs2013/grpc_shared.vcxproj.filters
@@ -253,6 +253,9 @@
     <ClCompile Include="..\..\src\core\surface\call_details.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+      <Filter>src\core\surface</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>
diff --git a/vsprojects/vs2013/grpc_unsecure.vcxproj b/vsprojects/vs2013/grpc_unsecure.vcxproj
index ad7bf47..ddf6982 100644
--- a/vsprojects/vs2013/grpc_unsecure.vcxproj
+++ b/vsprojects/vs2013/grpc_unsecure.vcxproj
@@ -300,6 +300,8 @@
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\call_details.c">
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
     </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel_create.c">
diff --git a/vsprojects/vs2013/grpc_unsecure.vcxproj.filters b/vsprojects/vs2013/grpc_unsecure.vcxproj.filters
index 205942a..38c7109 100644
--- a/vsprojects/vs2013/grpc_unsecure.vcxproj.filters
+++ b/vsprojects/vs2013/grpc_unsecure.vcxproj.filters
@@ -193,6 +193,9 @@
     <ClCompile Include="..\..\src\core\surface\call_details.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\core\surface\call_log_batch.c">
+      <Filter>src\core\surface</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\core\surface\channel.c">
       <Filter>src\core\surface</Filter>
     </ClCompile>