Basic data structure

: This article mainly introduces the basic data structure. if you are interested in the PHP Tutorial, you can refer to it. First, it is an integer:
Src/core/ngx_config.h

typedef intptr_t        ngx_int_t;typedef uintptr_t       ngx_uint_t;typedef intptr_t        ngx_flag_t;

It is an integer, an unsigned integer, and a bool. Intptr_t and other three types are defined as follows:
/Usr/local/include/stdint. h

/* Types for `void *' pointers.  */#if __WORDSIZE == 64# ifndef __intptr_t_definedtypedef longint        intptr_t;#  define __intptr_t_defined# endiftypedef unsigned longint   uintptr_t;#else# ifndef __intptr_t_definedtypedef int         intptr_t;#  define __intptr_t_defined# endiftypedef unsigned int        uintptr_t;#endif

That is, the 64 system uses a long integer (8 bytes); otherwise, an integer (4 bytes) is used ).

Then the string type:
/Src/core/ngx_string.h

typedef struct {    size_t      len;    u_char     *data;} ngx_str_t;

Next, we define a bunch of string-related functions, similar to the member functions corresponding to ngx_str_t.

Function	Description
Ngx_string (str)	Constructor. str points to the string ending with \ 0.
Ngx_null_string	Empty constructor
Ngx_str_set (str, text)	Text points to the string ending with \ 0 and sets it to the ngx_str_t object str
Ngx_strncmp	Encapsulate strncmp
Ngx_strcmp	Encapsulate strcmp
...	...

In addition, several other types are defined by the way:

Typedefstruct {ngx_str_t key; ngx_str_t value;} ngx_keyval_t; typedefstruct {// bit field used to indicate the type and other metadata unsigned len: 28; unsigned valid: 1; unsigned no_cacheable; unsigned not_found: 1; unsigned escape: 1; u_char * data;} ngx_variable_value_t; typedefstruct {ngx_rbtree_node_t node; ngx_str_t str;} ngx_str_node_t;

I defined my own error types: (the cause is that the strerror and strerror_r functions of the system are not signal secure. Therefore, the author copied the error msg corresponding to the error code and maintained it by himself, self-built functions are easy to write and signal-safe)
Src/OS/unix/ngx_errno.h

Typedefint ngx_err_t; // Copy the description information to errstr based on the error code err. you can copy the size byte u_char * ngx_strerror (ngx_err_t err, u_char * errstr, size_t size) at most ); ngx_int_t ngx_strerror_init (void );

The error number is defined in errno. h of the system. after multiple layers are included, the final error number is defined in/usr/include/asm-generic/errno. h.
The strerror and strerror_r functions are declared in string. h.

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The above introduces the basic data structure, including the content, and hope to be helpful to friends who are interested in PHP tutorials.