1package yaml
2
3const (
4	// The size of the input raw buffer.
5	input_raw_buffer_size = 512
6
7	// The size of the input buffer.
8	// It should be possible to decode the whole raw buffer.
9	input_buffer_size = input_raw_buffer_size * 3
10
11	// The size of the output buffer.
12	output_buffer_size = 128
13
14	// The size of the output raw buffer.
15	// It should be possible to encode the whole output buffer.
16	output_raw_buffer_size = (output_buffer_size*2 + 2)
17
18	// The size of other stacks and queues.
19	initial_stack_size  = 16
20	initial_queue_size  = 16
21	initial_string_size = 16
22)
23
24// Check if the character at the specified position is an alphabetical
25// character, a digit, '_', or '-'.
26func is_alpha(b []byte, i int) bool {
27	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'Z' || b[i] >= 'a' && b[i] <= 'z' || b[i] == '_' || b[i] == '-'
28}
29
30// Check if the character at the specified position is a digit.
31func is_digit(b []byte, i int) bool {
32	return b[i] >= '0' && b[i] <= '9'
33}
34
35// Get the value of a digit.
36func as_digit(b []byte, i int) int {
37	return int(b[i]) - '0'
38}
39
40// Check if the character at the specified position is a hex-digit.
41func is_hex(b []byte, i int) bool {
42	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'F' || b[i] >= 'a' && b[i] <= 'f'
43}
44
45// Get the value of a hex-digit.
46func as_hex(b []byte, i int) int {
47	bi := b[i]
48	if bi >= 'A' && bi <= 'F' {
49		return int(bi) - 'A' + 10
50	}
51	if bi >= 'a' && bi <= 'f' {
52		return int(bi) - 'a' + 10
53	}
54	return int(bi) - '0'
55}
56
57// Check if the character is ASCII.
58func is_ascii(b []byte, i int) bool {
59	return b[i] <= 0x7F
60}
61
62// Check if the character at the start of the buffer can be printed unescaped.
63func is_printable(b []byte, i int) bool {
64	return ((b[i] == 0x0A) || // . == #x0A
65		(b[i] >= 0x20 && b[i] <= 0x7E) || // #x20 <= . <= #x7E
66		(b[i] == 0xC2 && b[i+1] >= 0xA0) || // #0xA0 <= . <= #xD7FF
67		(b[i] > 0xC2 && b[i] < 0xED) ||
68		(b[i] == 0xED && b[i+1] < 0xA0) ||
69		(b[i] == 0xEE) ||
70		(b[i] == 0xEF && // #xE000 <= . <= #xFFFD
71			!(b[i+1] == 0xBB && b[i+2] == 0xBF) && // && . != #xFEFF
72			!(b[i+1] == 0xBF && (b[i+2] == 0xBE || b[i+2] == 0xBF))))
73}
74
75// Check if the character at the specified position is NUL.
76func is_z(b []byte, i int) bool {
77	return b[i] == 0x00
78}
79
80// Check if the beginning of the buffer is a BOM.
81func is_bom(b []byte, i int) bool {
82	return b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF
83}
84
85// Check if the character at the specified position is space.
86func is_space(b []byte, i int) bool {
87	return b[i] == ' '
88}
89
90// Check if the character at the specified position is tab.
91func is_tab(b []byte, i int) bool {
92	return b[i] == '\t'
93}
94
95// Check if the character at the specified position is blank (space or tab).
96func is_blank(b []byte, i int) bool {
97	//return is_space(b, i) || is_tab(b, i)
98	return b[i] == ' ' || b[i] == '\t'
99}
100
101// Check if the character at the specified position is a line break.
102func is_break(b []byte, i int) bool {
103	return (b[i] == '\r' || // CR (#xD)
104		b[i] == '\n' || // LF (#xA)
105		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
106		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
107		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9) // PS (#x2029)
108}
109
110func is_crlf(b []byte, i int) bool {
111	return b[i] == '\r' && b[i+1] == '\n'
112}
113
114// Check if the character is a line break or NUL.
115func is_breakz(b []byte, i int) bool {
116	//return is_break(b, i) || is_z(b, i)
117	return (        // is_break:
118	b[i] == '\r' || // CR (#xD)
119		b[i] == '\n' || // LF (#xA)
120		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
121		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
122		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
123		// is_z:
124		b[i] == 0)
125}
126
127// Check if the character is a line break, space, or NUL.
128func is_spacez(b []byte, i int) bool {
129	//return is_space(b, i) || is_breakz(b, i)
130	return ( // is_space:
131	b[i] == ' ' ||
132		// is_breakz:
133		b[i] == '\r' || // CR (#xD)
134		b[i] == '\n' || // LF (#xA)
135		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
136		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
137		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
138		b[i] == 0)
139}
140
141// Check if the character is a line break, space, tab, or NUL.
142func is_blankz(b []byte, i int) bool {
143	//return is_blank(b, i) || is_breakz(b, i)
144	return ( // is_blank:
145	b[i] == ' ' || b[i] == '\t' ||
146		// is_breakz:
147		b[i] == '\r' || // CR (#xD)
148		b[i] == '\n' || // LF (#xA)
149		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
150		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
151		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
152		b[i] == 0)
153}
154
155// Determine the width of the character.
156func width(b byte) int {
157	// Don't replace these by a switch without first
158	// confirming that it is being inlined.
159	if b&0x80 == 0x00 {
160		return 1
161	}
162	if b&0xE0 == 0xC0 {
163		return 2
164	}
165	if b&0xF0 == 0xE0 {
166		return 3
167	}
168	if b&0xF8 == 0xF0 {
169		return 4
170	}
171	return 0
172
173}
174