Zend/zend_types.h

Zend/zend_variables.h
Zend/zend_variables.c

struct

# 变量
struct _zval_struct {
  // 变量值
    zend_value        value;            /* value */

    union {
        struct {
            ZEND_ENDIAN_LOHI_4(
        // 变量类型
        // true，false，null 直接在type中区分 不存值
                zend_uchar    type,         /* active type */
        // GC时用到
                zend_uchar    type_flags,
                zend_uchar    const_flags,
                zend_uchar    reserved)     /* call info for EX(This) */
        } v;
    // 上面4个值的组合值
        uint32_t type_info;
    } u1;
  // 一些辅助值
    union {
        uint32_t     var_flags;
        uint32_t     next;                 /* hash collision chain */
        uint32_t     cache_slot;           /* literal cache slot */
        uint32_t     lineno;               /* line number (for ast nodes) */
        uint32_t     num_args;             /* arguments number for EX(This) */
        uint32_t     fe_pos;               /* foreach position */
        uint32_t     fe_iter_idx;          /* foreach iterator index */
    } u2;
};

# 变量值
typedef union _zend_value {
  // php整数 直接存储值
    zend_long         lval;             /* long value */
  // php中的浮点数 直接存储值
    double            dval;             /* double value */

    zend_refcounted  *counted;
  // 字符串
    zend_string      *str;
  // 数组
    zend_array       *arr;
  // 对象
    zend_object      *obj;
  // 资源型
    zend_resource    *res;
  // 引用类型
    zend_reference   *ref;

    zend_ast_ref     *ast;
    zval             *zv;
    void             *ptr;
    zend_class_entry *ce;
    zend_function    *func;
    struct {
        uint32_t w1;
        uint32_t w2;
    } ww;
} zend_value;

字符串 zend_string

# 字符串
struct _zend_string {
    zend_refcounted_h gc;
    zend_ulong        h;                /* hash value */
  // 二进制安全
    size_t            len;
    char              val[1];
};

zend_object

struct _zend_object {
    zend_refcounted_h gc;
    uint32_t          handle;
    zend_class_entry *ce;
    const zend_object_handlers *handlers;
    HashTable        *properties;
    zval              properties_table[1];
};

zend_resource

struct _zend_resource {
    zend_refcounted_h gc;
    int               handle;
    int               type;
    void             *ptr;
};

zend_reference

struct _zend_reference {
    zend_refcounted_h gc;
    zval              val;
};

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