From 29563523b210274f7fffa47b0c7b4e80292d5e41 Mon Sep 17 00:00:00 2001
From: Yehuda Sadeh <yehuda@hq.newdream.net>
Date: Thu, 14 May 2009 15:55:31 -0700
Subject: [PATCH] class: basic api for class, call class_init when class loads

---
 src/Makefile.am             |  3 ++-
 src/mon/ClassMonitor.cc     | 10 ++--------
 src/objclass/class_debug.cc | 25 +++++++++++++++++++++++++
 src/objclass/objclass.h     | 32 ++++++++++++++++++++++++++++++++
 src/osd/ClassHandler.cc     |  3 +++
 5 files changed, 64 insertions(+), 9 deletions(-)
 create mode 100644 src/objclass/class_debug.cc
 create mode 100644 src/objclass/objclass.h

diff --git a/src/Makefile.am b/src/Makefile.am
index a27a30011c16d..aa58d0e544c7a 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -221,7 +221,8 @@ libcommon_files = \
 	common/buffer.cc \
 	common/debug.cc \
 	config.cc \
-	common/lockdep.cc
+	common/lockdep.cc \
+        objclass/class_debug.cc
 
 libcrush_a_SOURCES = \
 	crush/builder.c \
diff --git a/src/mon/ClassMonitor.cc b/src/mon/ClassMonitor.cc
index 706b48aeed474..90ad59a0188cb 100644
--- a/src/mon/ClassMonitor.cc
+++ b/src/mon/ClassMonitor.cc
@@ -82,11 +82,8 @@ void ClassMonitor::create_initial(bufferlist& bl)
 
 bool ClassMonitor::store_impl(ClassInfo& info, ClassImpl& impl)
 {
-  char *store_name;
   int len = info.name.length() + 16;
-  store_name = (char *)malloc(len);
-  if (!store_name)
-    return false;
+  char store_name[len];
 
   snprintf(store_name, len, "%s.%d", info.name.c_str(), (int)info.version);
   dout(0) << "storing inc.impl length=" << impl.binary.length() << dendl;
@@ -95,7 +92,6 @@ bool ClassMonitor::store_impl(ClassInfo& info, ClassImpl& impl)
   ::encode(info, bl);
   mon->store->append_bl_ss(bl, "class_impl", store_name);
   dout(0) << "adding name=" << info.name << " version=" << info.version <<  " store_name=" << store_name << dendl;
-  free(store_name);
 
   return true;
 }
@@ -347,15 +343,13 @@ void ClassMonitor::handle_request(MClass *m)
     switch (m->action) {
     case CLASS_GET:
       if (list.get_ver((*p).name, &ver)) {
-        char *store_name;
         int len = (*p).name.length() + 16;
         int bin_len;
-        store_name = (char *)malloc(len);
+        char store_name[len];
         snprintf(store_name, len, "%s.%d", (*p).name.c_str(), ver);
         bin_len = mon->store->get_bl_ss(impl.binary, "class_impl", store_name);
         assert(bin_len > 0);
         dout(0) << "replying with name=" << (*p).name << " version=" << ver <<  " store_name=" << store_name << dendl;
-        free(store_name);
         list.add((*p).name, ver);
         reply->add.push_back(true);
         reply->impl.push_back(impl);
diff --git a/src/objclass/class_debug.cc b/src/objclass/class_debug.cc
new file mode 100644
index 0000000000000..35e470e8b8a86
--- /dev/null
+++ b/src/objclass/class_debug.cc
@@ -0,0 +1,25 @@
+#include "config.h"
+
+#include "objclass/objclass.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+
+extern "C" int cls_log(const char *format, ...)
+{
+   int size = 256, n;
+   va_list ap;
+   while (1) {
+     char buf[size];
+     va_start(ap, format);
+     n = vsnprintf(buf, size, format, ap);
+     va_end(ap);
+#define MAX_SIZE 8196
+     if ((n > -1 && n < size) || size > MAX_SIZE) {
+       dout(0) << buf << dendl;
+       return n;
+     }
+     size *= 2;
+   }
+}
diff --git a/src/objclass/objclass.h b/src/objclass/objclass.h
new file mode 100644
index 0000000000000..191ae88f129b6
--- /dev/null
+++ b/src/objclass/objclass.h
@@ -0,0 +1,32 @@
+#ifndef __OBJCLASS_H
+#define __OBJCLASS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void * ClsMethodHandle;
+
+
+#define OBJ_READ    0x1
+#define OBJ_WRITE   0x2
+
+typedef int ClsTrigger;
+
+/* class log */
+extern int cls_log(const char *format, ...);
+
+/* class registration api */
+extern int cls_register(const char *name, const char *method,
+                        int (*class_call)(struct ceph_osd_op *op, char **indata, int datalen, char **outdata, int *outdatalen),
+                        ClsMethodHandle *handle);
+extern int cls_unregister(ClsMethodHandle handle);
+
+extern int cls_link(ClsMethodHandle handle, int priority, ClsTrigger trigger);
+extern int cls_unlink(ClsMethodHandle handle);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/osd/ClassHandler.cc b/src/osd/ClassHandler.cc
index 79355add98427..6ba5d92db0cce 100644
--- a/src/osd/ClassHandler.cc
+++ b/src/osd/ClassHandler.cc
@@ -31,6 +31,9 @@ void ClassHandler::load_class(const nstring& cname)
   close(fd);
 
   data.handle = dlopen(fname, RTLD_LAZY);
+  void (*cls_init)() = (void (*)())dlsym(data.handle, "class_init");
+  if (cls_init)
+    cls_init();
 
   unlink(fname);
   free(fname);
-- 
2.39.5