Add new zend_hash_* APIs to UPGRADING.INTERNALS

Author: nikic

UPGRADING.INTERNALS

@@ -10,6 +10,8 @@ UPGRADE NOTES - PHP X.Y
  e. tsrm_virtual_cwd.h moved to zend_virtual_cwd.h
  f. empty strings are interned
  g. Additional str_* APIs
+ h. Addition of zend_hash_reindex
+ i. Addition of zend_hash_splice
 
 2. Build system changes
  a. Unix build system changes
@@ -137,6 +139,48 @@ UPGRADE NOTES - PHP X.Y
  str_hash(str, len) - INTERNED_HASH(str) if interned,
  zend_hash_func(str, len+1) otherwise
 
+ h. Addition of zend_hash_reindex
+
+ A zend_hash_reindex() function with the following prototype has been added:
+
+ void zend_hash_reindex(HashTable *ht, zend_bool only_integer_keys);
+
+ If only_integer_keys==0, this function will change all keys to be continuous,
+ zero-based integers in hash order. If only_integer_keys==1 the same will be
+ done only for keys that were already integers previously, while leaving
+ string keys alone.
+
+ i. Addition of zend_hash_splice
+
+ A zend_hash_splice() macro with the following prototype has been added:
+
+ void zend_hash_splice(
+ HashTable *ht, uint nDataSize, copy_ctor_func_t pCopyConstructor,
+ uint offset, uint length,
+ void **list, uint list_count, HashTable *removed
+ );
+
+ This function performs an in-place splice operation on a hashtable:
+
+ The elements between offset and offset+length are removed and the elements in
+ list[list_count] are inserted in their place. The removed elements can be
+ optionally collected into a hashtable.
+
+ This operation reindexes the hashtable, i.e. integer keys will be zero-based
+ and sequential, while string keys stay intact. The same applies to the
+ elements inserted into the removed HT.
+
+ As a side-effect of this addition the signature of the php_splice() function
+ changed:
+
+ void php_splice(
+ HashTable *ht, zend_uint offset, zend_uint length,
+ zval ***list, zend_uint list_count, HashTable *removed TSRMLS_DC
+ )
+ 
+ This function now directly forwards to zend_hash_splice(), resets the
+ IAP of ht (for compatibility with the previous implementation) and resets
+ CVs if the passed hashtable is the global symbol table.
 
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 2. Build system changes