From 540488bf55746a36363c56462e939a56550e3717 Mon Sep 17 00:00:00 2001
From: Dmitry Stogov <dmitry@zend.com>
Date: Mon, 10 Jun 2013 11:22:19 +0400
Subject: [PATCH] Compact HashTables before storing them in shared memory

---
 ext/opcache/ZendAccelerator.c             |  4 ++
 ext/opcache/zend_accelerator_util_funcs.c | 47 +++++++++++++++++++++++
 ext/opcache/zend_accelerator_util_funcs.h |  1 +
 3 files changed, 52 insertions(+)

diff --git a/ext/opcache/ZendAccelerator.c b/ext/opcache/ZendAccelerator.c
index b62f245f4c..212e1e68d0 100644
--- a/ext/opcache/ZendAccelerator.c
+++ b/ext/opcache/ZendAccelerator.c
@@ -1126,6 +1126,10 @@ static zend_persistent_script *cache_script_in_shared_memory(zend_persistent_scr
 		return new_persistent_script;
 	}
 
+	if (!compact_persistent_script(new_persistent_script)) {
+		return new_persistent_script;
+	}
+
 	/* exclusive lock */
 	zend_shared_alloc_lock(TSRMLS_C);
 
diff --git a/ext/opcache/zend_accelerator_util_funcs.c b/ext/opcache/zend_accelerator_util_funcs.c
index 33ecf7f183..c24d9f1304 100644
--- a/ext/opcache/zend_accelerator_util_funcs.c
+++ b/ext/opcache/zend_accelerator_util_funcs.c
@@ -86,6 +86,53 @@ zend_persistent_script* create_persistent_script(void)
 	return persistent_script;
 }
 
+static int compact_hash_table(HashTable *ht)
+{
+	uint i = 3;
+	uint nSize;
+	Bucket **t;
+
+	if (!ht->nNumOfElements) {
+		/* Empty tables don't allocate space for Buckets */
+		return 1;
+	}
+
+	if (ht->nNumOfElements >= 0x80000000) {
+		/* prevent overflow */
+		nSize = 0x80000000;
+	} else {
+		while ((1U << i) < ht->nNumOfElements) {
+			i++;
+		}
+		nSize = 1 << i;
+	}
+
+	if (nSize >= ht->nTableSize) {
+		/* Keep the size */
+		return 1;
+	}
+
+	t = (Bucket **)pemalloc(nSize * sizeof(Bucket *), ht->persistent);
+	if (!t) {
+		return 0;
+	}
+
+	pefree(ht->arBuckets, ht->persistent);
+
+	ht->arBuckets = t;
+	ht->nTableSize = nSize;
+	ht->nTableMask = ht->nTableSize - 1;
+	zend_hash_rehash(ht);
+	
+	return 1;
+}
+
+int compact_persistent_script(zend_persistent_script *persistent_script)
+{
+	return compact_hash_table(&persistent_script->function_table) &&
+	       compact_hash_table(&persistent_script->class_table);
+}
+
 void free_persistent_script(zend_persistent_script *persistent_script, int destroy_elements)
 {
 	if (destroy_elements) {
diff --git a/ext/opcache/zend_accelerator_util_funcs.h b/ext/opcache/zend_accelerator_util_funcs.h
index a926145c98..ddaae86b28 100644
--- a/ext/opcache/zend_accelerator_util_funcs.h
+++ b/ext/opcache/zend_accelerator_util_funcs.h
@@ -28,6 +28,7 @@
 void zend_accel_copy_internal_functions(TSRMLS_D);
 
 zend_persistent_script* create_persistent_script(void);
+int compact_persistent_script(zend_persistent_script *script);
 void free_persistent_script(zend_persistent_script *persistent_script, int destroy_elements);
 
 void zend_accel_free_user_functions(HashTable *ht TSRMLS_DC);
-- 
2.40.0