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