Geek Answers Handbook

Understanding the zend_execute APIs

I looked around a lot and never got a good book or any online documentation on zend_extensions [found quite a lot on PHP extensions, but not much on zend_extensions]. I am writing an extension and would like to do the following:

1. Capture state (mainly function call arguments) of currently executing functions. [I found a structure that contains some data about the function and studies it to find the names of the parameters of the function, but I cannot find their values. if zend_execute_data *execdis a pointer to a structure.

execd->function_state.function->common.(arg_info+i)->name)gives the name of the variable name ith agrument for the current function]. How to get the valuefor the i-th parameter. I know what I need to read from the stack. How to get a link to parameters on the stack? Is there a hash table or something else?

2. Secondly, how to skip the current executable function and move on to the next function / instruction in php script or replace the current function code with code from a cleaner or safer version of this function? From the zend_execute function.

Larger image . I am trying to get the state of a function and make some kind of decision on the execution thread of the interpreter based on the state of the function. I am trying to do all this from zend_execute( )located in my zend_extension, so I only have an API zend_execute( )to perform the above two tasks. Below is a list of the structures I went through and checked to find the value of the arguments of the current function.

struct _zend_execute_data {
    struct _zend_op *opline;
    zend_function_state function_state;
    zend_function *fbc; /* Function Being Called */
    zend_class_entry *called_scope;
    zend_op_array *op_array;
    zval *object;
    union _temp_variable *Ts;
    zval ***CVs;
    HashTable *symbol_table;
    struct _zend_execute_data *prev_execute_data;
    zval *old_error_reporting;
    zend_bool nested;
    zval **original_return_value;
    zend_class_entry *current_scope;
    zend_class_entry *current_called_scope;
    zval *current_this;
    zval *current_object;
};

links

typedef struct _zend_function_state {
    zend_function *function;
    void **arguments;
} zend_function_state;

link

typedef union _zend_function {
    zend_uchar type;  /* MUST be the first element of this struct! */

    struct {
        zend_uchar type;  /* never used */
        const char *function_name;
        zend_class_entry *scope;
        zend_uint fn_flags;
        union _zend_function *prototype;
        zend_uint num_args;
        zend_uint required_num_args;
        zend_arg_info *arg_info;
    } common;

    zend_op_array op_array;
    zend_internal_function internal_function;
} zend_function;

, . , . PHP , " PHP" .., API .

, , . Stack Overflow, , - , . , .

+4
1

, Zend. , void **, (zval **) (zval *), zval, zval . , .

typedef struct _zend_function_state {
    zend_function *function;
    void **arguments;
} zend_function_state;

:

ptr = (zval**)execd_init->function_state.arguments;
ptr1 = *(ptr-2);
ptr3 = *(ptr-1);
ptr2.value.str.val // gives the string value if type is string
ptr4.value.str.val // gives the second argument of type string
+1

More articles:


All Articles