defining a global object table

Forgive me for my n00bishness and this lengthy email, but I'm very new to the PHP code base and my C is quite rusty. I'm working on AMFEXT, trying to implement the serialization of objects and arrays by reference.  The basic idea is that arrays and objects, once encountered during the serialization of a data object, are listed in a global array.  If they are encountered again, then they are serialized as a reference rather than being stored all over again redundantly.  This allows for serialization of recursively defined data objects and reduces the size of the output string. In my source code (amf.c and php_amf.h) I am trying to define the global array of array/object references such that it satisfies these conditions: condition 1) the array is initialized as empty with each new call in a PHP script to the function amf_encode condition 2) the array is available within the scope of all my functions in amf.c condition 3) given an array or object to be serialized (e.g. zval *val parameter supplied to a function), I can search the array to check of val has been encountered previously condition 4) the array is destroyed and any memory it used is freed up once serialization is complete. condition 5) there is no danger of race conditions or data cross-talk between concurrent threads or processes or subsequent calls to amf_encode I believe this should be accomplished by: step 1) declaring something like this in php_amf.h: /* Declare any global variables you may need between the BEGIN and END macros here: */ ZEND_BEGIN_MODULE_GLOBALS(amf) zval **objects_and_arrays; // array containing memory addresses of arrays and objects encountered int objects_and_arrays_count; // number of serialized arrays/objects stored in the array int objects_and_arrays_allocated; // number of slots allocated for the array ZEND_END_MODULE_GLOBALS(amf) step 2) initialize the array at the entry point of the amf_encode function: /* The entry point for all calls to amf_encode */ static PHP_FUNCTION(amf_encode) { AMF_G(objects_and_arrays) = NULL; AMF_G(objects_and_arrays_count) = 0; AMF_G(objects_and_arrays_allocated) = 0; ... } step 3) when arrays/objects/zvals are encountered during serialization, store their memory address in the array Code TBD step 4) when serialization is complete, free the memory allocated to the array. Code TBD I have some questions question 1) Should I initialize my objects_and_arrays variables in the PHP_GINIT_FUNCTION instead? question 2) have I properly declared my objects_and_arrays variables? I.e., can I be sure there will be no crosstalk between threads or processes? question 3) when I allocate memory for my dynamic objects_and_arrays array, can I use realloc or should I use some other allocation function? I've seen lots of macros defining new function names in zend_alloc.h i expect to write an AddToArray function like the one described here: http://fydo.net/gamedev/dynamic-arrays question 4) when I allocate memory for my dynamic objects_and_arrays array, how much should I allocate per array element? Given that these are pointers, I expect they can be either 4 bytes or 8 depending on the OS. Are there any best practices for php development that might guide me in allocating memory for 32-bit vs. 64-bit systems? Can someone refer me to good source code examples? question 5) Does the overall approach I've outlined look sound? I'd be truly grateful for any advice, tips, heuristic guidelines, etc.