Reset handle table on destroy

[lttng-ust.git] / libust / lttng-ust-abi.c

diff --git a/libust/lttng-ust-abi.c b/libust/lttng-ust-abi.c
index 31eaa2a7cfc701b11a2f8ce6d2223cd43e707adb..ccaa17fa9ba56bbf3a9cf8a81b0d134ca27fe1bb 100644 (file)
--- a/libust/lttng-ust-abi.c
+++ b/libust/lttng-ust-abi.c
@@ -28,7 +28,7 @@
 #include <urcu/compiler.h>
 #include <urcu/list.h>
 #include <ust/lttng-events.h>
-#include "usterr_signal_safe.h"
+#include <ust/usterr-signal-safe.h>
 #include "ust/core.h"
 #include "ltt-tracer.h"
 
@@ -37,13 +37,6 @@
  * by the caller.
  */
 
-struct obj;
-
-struct objd_ops {
-       long (*cmd)(int objd, unsigned int cmd, unsigned long arg);
-       int (*release)(int objd);
-};
-
 struct obj {
        union {
                struct {
@@ -100,7 +93,8 @@ int objd_alloc(void *private_data, const struct objd_ops *ops)
 end:
        obj->u.s.private_data = private_data;
        obj->u.s.ops = ops;
-       obj->u.s.f_count = 1;
+       obj->u.s.f_count = 2;   /* count == 1 : object is allocated */
+                               /* count == 2 : allocated + hold ref */
        return obj - objd_table.array;
 }
 
@@ -109,6 +103,8 @@ struct obj *_objd_get(int id)
 {
        if (id >= objd_table.len)
                return NULL;
+       if (!objd_table.array[id].u.s.f_count)
+               return NULL;
        return &objd_table.array[id];
 }
 
@@ -128,11 +124,12 @@ void objd_set_private(int id, void *private_data)
        obj->u.s.private_data = private_data;
 }
 
-static
 const struct objd_ops *objd_ops(int id)
 {
        struct obj *obj = _objd_get(id);
-       assert(obj);
+
+       if (!obj)
+               return NULL;
        return obj->u.s.ops;
 }
 
@@ -144,6 +141,8 @@ void objd_free(int id)
        assert(obj);
        obj->u.freelist_next = objd_table.freelist_head;
        objd_table.freelist_head = obj - objd_table.array;
+       assert(obj->u.s.f_count == 1);
+       obj->u.s.f_count = 0;   /* deallocated */
 }
 
 static
@@ -153,24 +152,46 @@ void objd_ref(int id)
        obj->u.s.f_count++;
 }
 
-static
-void objd_unref(int id)
+int objd_unref(int id)
 {
        struct obj *obj = _objd_get(id);
 
-       if (!(--obj->u.s.f_count)) {
+       if (!obj)
+               return -EINVAL;
+       if (obj->u.s.f_count == 1) {
+               ERR("Reference counting error\n");
+               return -EINVAL;
+       }
+       if ((--obj->u.s.f_count) == 1) {
                const struct objd_ops *ops = objd_ops(id);
-
+               
                if (ops->release)
                        ops->release(id);
                objd_free(id);
        }
+       return 0;
 }
 
 static
 void objd_table_destroy(void)
 {
+       int i;
+
+       for (i = 0; i < objd_table.allocated_len; i++) {
+               struct obj *obj = _objd_get(i);
+               const struct objd_ops *ops;
+
+               if (!obj)
+                       continue;
+               ops = obj->u.s.ops;
+               if (ops->release)
+                       ops->release(i);
+       }
        free(objd_table.array);
+       objd_table.array = NULL;
+       objd_table.len = 0;
+       objd_table.allocated_len = 0;
+       objd_table.freelist_head = -1;
 }
 
 /*
@@ -189,6 +210,15 @@ enum channel_type {
        METADATA_CHANNEL,
 };
 
+int lttng_abi_create_root_handle(void)
+{
+       int root_handle;
+
+       root_handle = objd_alloc(NULL, &lttng_ops);
+       assert(root_handle == 0);
+       return root_handle;
+}
+
 static
 int lttng_abi_create_session(void)
 {
@@ -251,7 +281,7 @@ long lttng_abi_add_context(int objd,
 
        switch (context_param->ctx) {
        case LTTNG_UST_CONTEXT_VTID:
-               return lttng_add_vtid_to_ctx(ctx);
+               //TODO return lttng_add_vtid_to_ctx(ctx);
        default:
                return -EINVAL;
        }
@@ -332,7 +362,6 @@ create_error:
        return;         /* not allowed to return error */
 }
 
-static
 int lttng_abi_create_channel(int session_objd,
                             struct lttng_ust_channel *chan_param,
                             enum channel_type channel_type)
@@ -396,7 +425,12 @@ int lttng_abi_create_channel(int session_objd,
        return chan_objd;
 
 chan_error:
-       objd_unref(chan_objd);
+       {
+               int err;
+
+               err = objd_unref(chan_objd);
+               assert(!err);
+       }
 objd_error:
        return ret;
 }
@@ -454,17 +488,20 @@ long lttng_session_cmd(int objd, unsigned int cmd, unsigned long arg)
  * individual file is released).
  */
 static
-int lttng_session_release(int objd)
+int lttng_release_session(int objd)
 {
        struct ltt_session *session = objd_private(objd);
 
-       if (session)
+       if (session) {
                ltt_session_destroy(session);
-       return 0;
+               return 0;
+       } else {
+               return -EINVAL;
+       }
 }
 
 static const struct objd_ops lttng_session_ops = {
-       .release = lttng_session_release,
+       .release = lttng_release_session,
        .cmd = lttng_session_cmd,
 };
 
@@ -527,7 +564,12 @@ int lttng_abi_create_event(int channel_objd,
        return event_objd;
 
 event_error:
-       objd_unref(event_objd);
+       {
+               int err;
+
+               err = objd_unref(event_objd);
+               assert(!err);
+       }
 objd_error:
        return ret;
 }
@@ -639,7 +681,7 @@ int lttng_channel_release(int objd)
        struct ltt_channel *channel = objd_private(objd);
 
        if (channel)
-               objd_unref(channel->session->objd);
+               return objd_unref(channel->session->objd);
        return 0;
 }
 
@@ -694,7 +736,7 @@ int lttng_event_release(int objd)
        struct ltt_event *event = objd_private(objd);
 
        if (event)
-               objd_unref(event->chan->objd);
+               return objd_unref(event->chan->objd);
        return 0;
 }
 
@@ -704,14 +746,7 @@ static const struct objd_ops lttng_event_ops = {
        .cmd = lttng_event_cmd,
 };
 
-void __attribute__((constructor)) lttng_ust_abi_init(void)
-{
-       /* TODO: initialize socket */
-}
-
-static
-void __attribute__((destructor)) lttng_ust_abi_exit(void)
+void lttng_ust_abi_exit(void)
 {
-       /* TODO: teardown socket */
        objd_table_destroy();
 }