From c940f107b75694c3272ca98cb69b9d7df8cd2d0b Mon Sep 17 00:00:00 2001

Message-Id: <c940f107b75694c3272ca98cb69b9d7df8cd2d0b@dist-git>

From: Jiri Denemark <jdenemar@redhat.com>

Date: Thu, 2 Jul 2015 14:21:27 +0200

Subject: [PATCH] Introduce virHashAtomic

This is a self-locking wrapper around virHashTable. Only a limited set

of APIs are implemented now (the ones which are used in the following

patch) as more can be added on demand.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

(cherry picked from commit a7c22a1f2949e781aef4aa82afda407efd344f95)

https://bugzilla.redhat.com/show_bug.cgi?id=1090093

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/libvirt_private.syms |  3 ++

 src/util/virhash.c       | 81 ++++++++++++++++++++++++++++++++++++++++++++++++

 src/util/virhash.h       | 10 ++++++

 3 files changed, 94 insertions(+)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index 720afdf..65168b1 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -1476,6 +1476,9 @@ virFirewallStartTransaction;

 # util/virhash.h

 virHashAddEntry;

+virHashAtomicNew;

+virHashAtomicSteal;

+virHashAtomicUpdate;

 virHashCreate;

 virHashEqual;

 virHashForEach;

diff --git a/src/util/virhash.c b/src/util/virhash.c

index e3c1880..3cfcc69 100644

--- a/src/util/virhash.c

+++ b/src/util/virhash.c

@@ -31,6 +31,7 @@

 #include "virhashcode.h"

 #include "virrandom.h"

 #include "virstring.h"

+#include "virobject.h"

 #define VIR_FROM_THIS VIR_FROM_NONE

@@ -76,6 +77,28 @@ struct _virHashTable {

     virHashKeyFree keyFree;

 };

+struct _virHashAtomic {

+    virObjectLockable parent;

+    virHashTablePtr hash;

+};

+

+static virClassPtr virHashAtomicClass;

+static void virHashAtomicDispose(void *obj);

+

+static int virHashAtomicOnceInit(void)

+{

+    virHashAtomicClass = virClassNew(virClassForObjectLockable(),

+                                     "virHashAtomic",

+                                     sizeof(virHashAtomic),

+                                     virHashAtomicDispose);

+    if (!virHashAtomicClass)

+        return -1;

+    else

+        return 0;

+}

+VIR_ONCE_GLOBAL_INIT(virHashAtomic)

+

+

 static uint32_t virHashStrCode(const void *name, uint32_t seed)

 {

     return virHashCodeGen(name, strlen(name), seed);

@@ -178,6 +201,36 @@ virHashTablePtr virHashCreate(ssize_t size, virHashDataFree dataFree)

                              virHashStrFree);

 }

+

+virHashAtomicPtr

+virHashAtomicNew(ssize_t size,

+                 virHashDataFree dataFree)

+{

+    virHashAtomicPtr hash;

+

+    if (virHashAtomicInitialize() < 0)

+        return NULL;

+

+    if (!(hash = virObjectLockableNew(virHashAtomicClass)))

+        return NULL;

+

+    if (!(hash->hash = virHashCreate(size, dataFree))) {

+        virObjectUnref(hash);

+        return NULL;

+    }

+    return hash;

+}

+

+

+static void

+virHashAtomicDispose(void *obj)

+{

+    virHashAtomicPtr hash = obj;

+

+    virHashFree(hash->hash);

+}

+

+

 /**

  * virHashGrow:

  * @table: the hash table

@@ -360,6 +413,21 @@ virHashUpdateEntry(virHashTablePtr table, const void *name,

     return virHashAddOrUpdateEntry(table, name, userdata, true);

 }

+int

+virHashAtomicUpdate(virHashAtomicPtr table,

+                    const void *name,

+                    void *userdata)

+{

+    int ret;

+

+    virObjectLock(table);

+    ret = virHashAddOrUpdateEntry(table->hash, name, userdata, true);

+    virObjectUnlock(table);

+

+    return ret;

+}

+

+

 /**

  * virHashLookup:

  * @table: the hash table

@@ -409,6 +477,19 @@ void *virHashSteal(virHashTablePtr table, const void *name)

     return data;

 }

+void *

+virHashAtomicSteal(virHashAtomicPtr table,

+                   const void *name)

+{

+    void *data;

+

+    virObjectLock(table);

+    data = virHashSteal(table->hash, name);

+    virObjectUnlock(table);

+

+    return data;

+}

+

 /**

  * virHashSize:

diff --git a/src/util/virhash.h b/src/util/virhash.h

index a137137..50b9a04 100644

--- a/src/util/virhash.h

+++ b/src/util/virhash.h

@@ -21,6 +21,9 @@

 typedef struct _virHashTable virHashTable;

 typedef virHashTable *virHashTablePtr;

+typedef struct _virHashAtomic virHashAtomic;

+typedef virHashAtomic *virHashAtomicPtr;

+

 /*

  * function types:

  */

@@ -101,6 +104,8 @@ typedef void (*virHashKeyFree)(void *name);

  */

 virHashTablePtr virHashCreate(ssize_t size,

                               virHashDataFree dataFree);

+virHashAtomicPtr virHashAtomicNew(ssize_t size,

+                                  virHashDataFree dataFree);

 virHashTablePtr virHashCreateFull(ssize_t size,

                                   virHashDataFree dataFree,

                                   virHashKeyCode keyCode,

@@ -119,6 +124,9 @@ int virHashAddEntry(virHashTablePtr table,

 int virHashUpdateEntry(virHashTablePtr table,

                        const void *name,

                        void *userdata);

+int virHashAtomicUpdate(virHashAtomicPtr table,

+                        const void *name,

+                        void *userdata);

 /*

  * Remove an entry from the hash table.

@@ -140,6 +148,8 @@ void *virHashLookup(const virHashTable *table, const void *name);

  * Retrieve & remove the userdata.

  */

 void *virHashSteal(virHashTablePtr table, const void *name);

+void *virHashAtomicSteal(virHashAtomicPtr table,

+                         const void *name);

 /*

  * Get the hash table's key/value pairs and have them optionally sorted.

-- 

2.4.5