finish vma

source/server/vnode/inc/vnodeMemAllocator.h

@@ -16,12 +16,39 @@
 #ifndef _TD_VNODE_MEM_ALLOCATOR_H_
 #define _TD_VNODE_MEM_ALLOCATOR_H_
 
-#include "amalloc.h"
+#include "os.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+typedef struct SVMANode           SVMANode;
+typedef struct SVnodeMemAllocator SVnodeMemAllocator;
+
+SVnodeMemAllocator *VMACreate(size_t size /* base size */, size_t ssize /* step size */,
+                              size_t threshold /* threshold size when full*/);
+void                VMADestroy(SVnodeMemAllocator *pvma);
+void                VMAReset(SVnodeMemAllocator *pvma);
+void *              VMAMalloc(SVnodeMemAllocator *pvma, size_t size);
+void                VMAFree(SVnodeMemAllocator *pvma, void *ptr);
+bool                VMAIsFull(SVnodeMemAllocator *pvma);
+
+// ------------------ FOR TEST ONLY ------------------
+struct SVMANode {
+  struct SVMANode *prev;
+  size_t           tsize;
+  size_t           used;
+  char             data[];
+};
+
+struct SVnodeMemAllocator {
+  bool      full;       // if allocator is full
+  size_t    threshold;  // threshold;
+  size_t    ssize;      // step size to allocate
+  SVMANode *inuse;      // inuse node to allocate
+  SVMANode  node;       // basic node to use
+};
+
 #ifdef __cplusplus
 }
 #endif

source/server/vnode/src/vnodeMemAllocator.c

@@ -11,4 +11,114 @@
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
\ No newline at end of file
+ */
+
+#include "vnodeMemAllocator.h"
+
+#define VMA_IS_FULL(pvma) \
+  (((pvma)->inuse != &((pvma)->node)) || ((pvma)->inuse->tsize - (pvma)->inuse->used < (pvma)->threshold))
+
+static SVMANode *VMANodeNew(size_t size);
+static void      VMANodeFree(SVMANode *node);
+
+SVnodeMemAllocator *VMACreate(size_t size, size_t ssize, size_t threshold) {
+  SVnodeMemAllocator *pvma = NULL;
+
+  if (size < threshold) {
+    return NULL;
+  }
+
+  pvma = (SVnodeMemAllocator *)malloc(sizeof(*pvma) + size);
+  if (pvma) {
+    pvma->full = false;
+    pvma->threshold = threshold;
+    pvma->ssize = ssize;
+    pvma->inuse = &(pvma->node);
+
+    pvma->inuse->prev = NULL;
+    pvma->inuse->tsize = size;
+    pvma->inuse->used = 0;
+  }
+
+  return pvma;
+}
+
+void VMADestroy(SVnodeMemAllocator *pvma) {
+  if (pvma) {
+    VMAReset(pvma);
+    free(pvma);
+  }
+}
+
+void VMAReset(SVnodeMemAllocator *pvma) {
+  while (pvma->inuse != &(pvma->node)) {
+    SVMANode *node = pvma->inuse;
+    pvma->inuse = node->prev;
+    VMANodeFree(node);
+  }
+
+  pvma->inuse->used = 0;
+  pvma->full = false;
+}
+
+void *VMAMalloc(SVnodeMemAllocator *pvma, size_t size) {
+  void * ptr = NULL;
+  size_t tsize = size + sizeof(size_t);
+
+  if (pvma->inuse->tsize - pvma->inuse->used < tsize) {
+    SVMANode *pNode = VMANodeNew(MAX(pvma->ssize, tsize));
+    if (pNode == NULL) {
+      return NULL;
+    }
+
+    pNode->prev = pvma->inuse;
+    pvma->inuse = pNode;
+  }
+
+  ptr = pvma->inuse->data + pvma->inuse->used;
+  pvma->inuse->used += tsize;
+  *(size_t *)ptr = size;
+  ptr = POINTER_SHIFT(ptr, sizeof(size_t));
+
+  pvma->full = VMA_IS_FULL(pvma);
+
+  return ptr;
+}
+
+void VMAFree(SVnodeMemAllocator *pvma, void *ptr) {
+  if (ptr) {
+    size_t size = *(size_t *)POINTER_SHIFT(ptr, -sizeof(size_t));
+    if (POINTER_SHIFT(ptr, size) == pvma->inuse->data + pvma->inuse->used) {
+      pvma->inuse->used -= (size + sizeof(size_t));
+
+      if ((pvma->inuse->used == 0) && (pvma->inuse != &(pvma->node))) {
+        SVMANode *node = pvma->inuse;
+        pvma->inuse = node->prev;
+        VMANodeFree(node);
+      }
+
+      pvma->full = VMA_IS_FULL(pvma);
+    }
+  }
+}
+
+bool VMAIsFull(SVnodeMemAllocator *pvma) { return pvma->full; }
+
+static SVMANode *VMANodeNew(size_t size) {
+  SVMANode *node = NULL;
+
+  node = (SVMANode *)malloc(sizeof(*node) + size);
+  if (node) {
+    node->prev = NULL;
+    node->tsize = size;
+    node->used = 0;
+  }
+
+  return node;
+}
+
+static void VMANodeFree(SVMANode *node) {
+  if (node) {
+    free(node);
+  }
+}
\ No newline at end of file