php內核解析(四)全局變量

這裏閱讀的php版本爲PHP-7.1.0 RC3，閱讀代碼的平臺爲linux

CG

CG是從全局的compiler_global中獲取屬性值，裏面存儲的就是編譯過程使用到的全局變量。

struct _zend_compiler_globals { zend_stack loop_var_stack; zend_class_entry *active_class_entry; zend_string *compiled_filename; int zend_lineno; zend_op_array *active_op_array; HashTable *function_table; /* function symbol table */ HashTable *class_table; /* class table */ HashTable filenames_table; HashTable *auto_globals; zend_bool parse_error; zend_bool in_compilation; zend_bool short_tags; zend_bool unclean_shutdown; zend_bool ini_parser_unbuffered_errors; zend_llist open_files; struct _zend_ini_parser_param *ini_parser_param; uint32_t start_lineno; // 執行文件開始執行的行號 zend_bool increment_lineno; zend_string *doc_comment; uint32_t extra_fn_flags; uint32_t compiler_options; /* set of ZEND_COMPILE_* constants */ HashTable const_filenames; zend_oparray_context context; zend_file_context file_context; zend_arena *arena; zend_string *empty_string; zend_string *one_char_string[256]; zend_string **known_strings; uint32_t known_strings_count; HashTable interned_strings; const zend_encoding **script_encoding_list; size_t script_encoding_list_size; zend_bool multibyte; zend_bool detect_unicode; zend_bool encoding_declared; zend_ast *ast; zend_arena *ast_arena; zend_stack delayed_oplines_stack; #ifdef ZTS zval **static_members_table; int last_static_member; #endif };

SG

SG是從全局的sapi_global中獲取屬性值

// TODO：更新 typedef struct _sapi_globals_struct { void *server_context; sapi_request_info request_info; // 請求信息 sapi_headers_struct sapi_headers; int64_t read_post_bytes; unsigned char post_read; unsigned char headers_sent; zend_stat_t global_stat; char *default_mimetype; char *default_charset; HashTable *rfc1867_uploaded_files; zend_long post_max_size; int options; zend_bool sapi_started; double global_request_time; HashTable known_post_content_types; zval callback_func; zend_fcall_info_cache fci_cache; } sapi_globals_struct;

EG

EG是從executor_globals中獲取變量

// TODO: 更新 struct _zend_executor_globals { zval uninitialized_zval; zval error_zval; /* symbol table cache */ zend_array *symtable_cache[SYMTABLE_CACHE_SIZE]; zend_array **symtable_cache_limit; zend_array **symtable_cache_ptr; zend_array symbol_table; /* main symbol table */ HashTable included_files; /* files already included */ JMP_BUF *bailout; int error_reporting; int exit_status; HashTable *function_table; /* function symbol table */ HashTable *class_table; /* class table */ HashTable *zend_constants; /* constants table */ zval *vm_stack_top; zval *vm_stack_end; zend_vm_stack vm_stack; struct _zend_execute_data *current_execute_data; zend_class_entry *fake_scope; /* used to avoid checks accessing properties */ zend_long precision; int ticks_count; HashTable *in_autoload; zend_function *autoload_func; zend_bool full_tables_cleanup; /* for extended information support */ zend_bool no_extensions; zend_bool vm_interrupt; zend_bool timed_out; zend_long hard_timeout; #ifdef ZEND_WIN32 OSVERSIONINFOEX windows_version_info; #endif HashTable regular_list; HashTable persistent_list; int user_error_handler_error_reporting; zval user_error_handler; zval user_exception_handler; zend_stack user_error_handlers_error_reporting; zend_stack user_error_handlers; zend_stack user_exception_handlers; zend_error_handling_t error_handling; zend_class_entry *exception_class; /* timeout support */ zend_long timeout_seconds; int lambda_count; HashTable *ini_directives; HashTable *modified_ini_directives; zend_ini_entry *error_reporting_ini_entry; zend_objects_store objects_store; zend_object *exception, *prev_exception; const zend_op *opline_before_exception; zend_op exception_op[3]; struct _zend_module_entry *current_module; zend_bool active; zend_bool valid_symbol_table; zend_long assertions; uint32_t ht_iterators_count; /* number of allocatd slots */ uint32_t ht_iterators_used; /* number of used slots */ HashTableIterator *ht_iterators; HashTableIterator ht_iterators_slots[16]; void *saved_fpu_cw_ptr; #if XPFPA_HAVE_CW XPFPA_CW_DATATYPE saved_fpu_cw; #endif zend_function trampoline; zend_op call_trampoline_op; void *reserved[ZEND_MAX_RESERVED_RESOURCES]; };