PART 4: String handling

结构体
struct	StrPoolPtr

宏定义
#define	POOLPOINTER_IS_POINTER   1
#define	POOL_TOP   (str_pool + POOL_SIZE)
#define	POOL_ELEM(x, y)   ((x)[(y)])
#define	S(x)   (x)
	标记字符串序号 更多...

类型定义
typedef ASCIICode *	PoolPtr
	[#38] for variables that point into str_pool. 更多...
typedef uint_fast32_t	StrNumber
typedef char *	Str
	real string. 更多...

函数
int	str_length (StrNumber x)
	[#40]: the number of characters in string number x. 更多...
int	cur_length ()
	[#41]: The length of the current string. 更多...
void	append_char (ASCIICode s)
	[#42]: put ASCII code s at the end of str_pool. 更多...
void	flush_char (void)
	[#42]: forget the last character in the pool. 更多...
void	str_room (StrNumber l)
	[#42]: make sure that the pool hasn’t overflowed. 更多...
StrNumber	makestring (void)
	[#43]: current string enters the pool. 更多...
void	flush_string (void)
	[#44]: destroy the most recently made string. 更多...
int	str_cmp (StrNumber s, StrNumber t)
	比较两个 str 的差别。返回 0 为相同，非 0 为有差异。 更多...
Boolean	str_eq_str (StrNumber s, StrNumber t)
	[p21#46]: test equality of strings。 更多...
Boolean	get_strings_started (void)
	[#47]: initializes the string pool, but returns false if something goes wrong. 更多...
static void	app_lc_hex (UChar l)
	[#48] int to hex 更多...
Boolean	str_pool_init (void)
	[p21#47] Make the first 256 strings, and copy all string in pool_strs[] to string pool. 更多...

变量
static ASCIICode	str_pool [POOL_SIZE+1]
	[#39] the characters. 更多...
static PoolPtr	str_start [MAX_STRINGS+1]
	[#39] the starting pointers. 更多...
static PoolPtr	pool_ptr
	[#39] first unused position in str_pool. 更多...
static StrNumber	str_ptr
	[#39] number of the current string being created. 更多...
static PoolPtr	init_pool_ptr
	[#39] the starting value of pool_ptr. 更多...
static StrNumber	init_str_ptr
	[#39] the starting value of str_ptr. 更多...

详细描述

宏定义说明

POOL_ELEM

#define POOL_ELEM	(		x,
			y
	)		((x)[(y)])

POOL_TOP

#define POOL_TOP   (str_pool + POOL_SIZE)

POOLPOINTER_IS_POINTER

#define POOLPOINTER_IS_POINTER   1

S

#define S

(

x

)

(x)

标记字符串序号

类型定义说明

PoolPtr

typedef ASCIICode* PoolPtr

[#38] for variables that point into str_pool.

[PoolPointer => PoolPtr], [0, POOL_SIZE=4MB-1B]

Str

typedef char* Str

real string.

StrNumber

typedef uint_fast32_t StrNumber

函数说明

app_lc_hex()

static void app_lc_hex ( UChar  l )

static

[#48] int to hex

append_char()

void append_char

(

ASCIICode

s

)

[#42]: put ASCII code s at the end of str_pool.

cur_length()

int cur_length

(

void

)

[#41]: The length of the current string.

flush_char()

void flush_char

(

void

)

[#42]: forget the last character in the pool.

flush_string()

void flush_string

(

void

)

[#44]: destroy the most recently made string.

get_strings_started()

Boolean get_strings_started

(

void

)

[#47]: initializes the string pool, but returns false if something goes wrong.

called by: main()

makestring()

StrNumber makestring

(

void

)

[#43]: current string enters the pool.

Once a sequence of characters has been appended to str pool, it officially becomes a string when the function make string is called.

This function returns the identification number of the new string as its value.

str_cmp()

int str_cmp	(	StrNumber	s,
		StrNumber	t
	)

比较两个 str 的差别。返回 0 为相同，非 0 为有差异。

str_eq_str()

Boolean str_eq_str	(	StrNumber	s,
		StrNumber	t
	)

[p21#46]: test equality of strings。

str_length()

int str_length

(

StrNumber

x

)

[#40]: the number of characters in string number x.

str_pool_init()

Boolean str_pool_init

(

void

)

[p21#47] Make the first 256 strings, and copy all string in pool_strs[] to string pool.

length of pool_strs[].

[#48] Make the first 256 strings. ASCII 输入表见 TeXBook: Appendix C: Character Codes.

[#52] Copy strings from 'pool_strs[]' to the pool

str_room()

void str_room

(

StrNumber

l

)

[#42]: make sure that the pool hasn’t overflowed.

变量说明

init_pool_ptr

PoolPtr init_pool_ptr

static

[#39] the starting value of pool_ptr.

init_str_ptr

StrNumber init_str_ptr

static

[#39] the starting value of str_ptr.

pool_ptr

PoolPtr pool_ptr

static

[#39] first unused position in str_pool.

str_pool

ASCIICode str_pool[POOL_SIZE+1]

static

[#39] the characters.

str_ptr

StrNumber str_ptr

static

[#39] number of the current string being created.

str_start

PoolPtr str_start[MAX_STRINGS+1]

static

[#39] the starting pointers.