diff options
Diffstat (limited to 'vendor/github.com/zclconf/go-cty-yaml/readerc.go')
-rw-r--r-- | vendor/github.com/zclconf/go-cty-yaml/readerc.go | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/vendor/github.com/zclconf/go-cty-yaml/readerc.go b/vendor/github.com/zclconf/go-cty-yaml/readerc.go new file mode 100644 index 0000000..7c1f5fa --- /dev/null +++ b/vendor/github.com/zclconf/go-cty-yaml/readerc.go | |||
@@ -0,0 +1,412 @@ | |||
1 | package yaml | ||
2 | |||
3 | import ( | ||
4 | "io" | ||
5 | ) | ||
6 | |||
7 | // Set the reader error and return 0. | ||
8 | func yaml_parser_set_reader_error(parser *yaml_parser_t, problem string, offset int, value int) bool { | ||
9 | parser.error = yaml_READER_ERROR | ||
10 | parser.problem = problem | ||
11 | parser.problem_offset = offset | ||
12 | parser.problem_value = value | ||
13 | return false | ||
14 | } | ||
15 | |||
16 | // Byte order marks. | ||
17 | const ( | ||
18 | bom_UTF8 = "\xef\xbb\xbf" | ||
19 | bom_UTF16LE = "\xff\xfe" | ||
20 | bom_UTF16BE = "\xfe\xff" | ||
21 | ) | ||
22 | |||
23 | // Determine the input stream encoding by checking the BOM symbol. If no BOM is | ||
24 | // found, the UTF-8 encoding is assumed. Return 1 on success, 0 on failure. | ||
25 | func yaml_parser_determine_encoding(parser *yaml_parser_t) bool { | ||
26 | // Ensure that we had enough bytes in the raw buffer. | ||
27 | for !parser.eof && len(parser.raw_buffer)-parser.raw_buffer_pos < 3 { | ||
28 | if !yaml_parser_update_raw_buffer(parser) { | ||
29 | return false | ||
30 | } | ||
31 | } | ||
32 | |||
33 | // Determine the encoding. | ||
34 | buf := parser.raw_buffer | ||
35 | pos := parser.raw_buffer_pos | ||
36 | avail := len(buf) - pos | ||
37 | if avail >= 2 && buf[pos] == bom_UTF16LE[0] && buf[pos+1] == bom_UTF16LE[1] { | ||
38 | parser.encoding = yaml_UTF16LE_ENCODING | ||
39 | parser.raw_buffer_pos += 2 | ||
40 | parser.offset += 2 | ||
41 | } else if avail >= 2 && buf[pos] == bom_UTF16BE[0] && buf[pos+1] == bom_UTF16BE[1] { | ||
42 | parser.encoding = yaml_UTF16BE_ENCODING | ||
43 | parser.raw_buffer_pos += 2 | ||
44 | parser.offset += 2 | ||
45 | } else if avail >= 3 && buf[pos] == bom_UTF8[0] && buf[pos+1] == bom_UTF8[1] && buf[pos+2] == bom_UTF8[2] { | ||
46 | parser.encoding = yaml_UTF8_ENCODING | ||
47 | parser.raw_buffer_pos += 3 | ||
48 | parser.offset += 3 | ||
49 | } else { | ||
50 | parser.encoding = yaml_UTF8_ENCODING | ||
51 | } | ||
52 | return true | ||
53 | } | ||
54 | |||
55 | // Update the raw buffer. | ||
56 | func yaml_parser_update_raw_buffer(parser *yaml_parser_t) bool { | ||
57 | size_read := 0 | ||
58 | |||
59 | // Return if the raw buffer is full. | ||
60 | if parser.raw_buffer_pos == 0 && len(parser.raw_buffer) == cap(parser.raw_buffer) { | ||
61 | return true | ||
62 | } | ||
63 | |||
64 | // Return on EOF. | ||
65 | if parser.eof { | ||
66 | return true | ||
67 | } | ||
68 | |||
69 | // Move the remaining bytes in the raw buffer to the beginning. | ||
70 | if parser.raw_buffer_pos > 0 && parser.raw_buffer_pos < len(parser.raw_buffer) { | ||
71 | copy(parser.raw_buffer, parser.raw_buffer[parser.raw_buffer_pos:]) | ||
72 | } | ||
73 | parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)-parser.raw_buffer_pos] | ||
74 | parser.raw_buffer_pos = 0 | ||
75 | |||
76 | // Call the read handler to fill the buffer. | ||
77 | size_read, err := parser.read_handler(parser, parser.raw_buffer[len(parser.raw_buffer):cap(parser.raw_buffer)]) | ||
78 | parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)+size_read] | ||
79 | if err == io.EOF { | ||
80 | parser.eof = true | ||
81 | } else if err != nil { | ||
82 | return yaml_parser_set_reader_error(parser, "input error: "+err.Error(), parser.offset, -1) | ||
83 | } | ||
84 | return true | ||
85 | } | ||
86 | |||
87 | // Ensure that the buffer contains at least `length` characters. | ||
88 | // Return true on success, false on failure. | ||
89 | // | ||
90 | // The length is supposed to be significantly less that the buffer size. | ||
91 | func yaml_parser_update_buffer(parser *yaml_parser_t, length int) bool { | ||
92 | if parser.read_handler == nil { | ||
93 | panic("read handler must be set") | ||
94 | } | ||
95 | |||
96 | // [Go] This function was changed to guarantee the requested length size at EOF. | ||
97 | // The fact we need to do this is pretty awful, but the description above implies | ||
98 | // for that to be the case, and there are tests | ||
99 | |||
100 | // If the EOF flag is set and the raw buffer is empty, do nothing. | ||
101 | if parser.eof && parser.raw_buffer_pos == len(parser.raw_buffer) { | ||
102 | // [Go] ACTUALLY! Read the documentation of this function above. | ||
103 | // This is just broken. To return true, we need to have the | ||
104 | // given length in the buffer. Not doing that means every single | ||
105 | // check that calls this function to make sure the buffer has a | ||
106 | // given length is Go) panicking; or C) accessing invalid memory. | ||
107 | //return true | ||
108 | } | ||
109 | |||
110 | // Return if the buffer contains enough characters. | ||
111 | if parser.unread >= length { | ||
112 | return true | ||
113 | } | ||
114 | |||
115 | // Determine the input encoding if it is not known yet. | ||
116 | if parser.encoding == yaml_ANY_ENCODING { | ||
117 | if !yaml_parser_determine_encoding(parser) { | ||
118 | return false | ||
119 | } | ||
120 | } | ||
121 | |||
122 | // Move the unread characters to the beginning of the buffer. | ||
123 | buffer_len := len(parser.buffer) | ||
124 | if parser.buffer_pos > 0 && parser.buffer_pos < buffer_len { | ||
125 | copy(parser.buffer, parser.buffer[parser.buffer_pos:]) | ||
126 | buffer_len -= parser.buffer_pos | ||
127 | parser.buffer_pos = 0 | ||
128 | } else if parser.buffer_pos == buffer_len { | ||
129 | buffer_len = 0 | ||
130 | parser.buffer_pos = 0 | ||
131 | } | ||
132 | |||
133 | // Open the whole buffer for writing, and cut it before returning. | ||
134 | parser.buffer = parser.buffer[:cap(parser.buffer)] | ||
135 | |||
136 | // Fill the buffer until it has enough characters. | ||
137 | first := true | ||
138 | for parser.unread < length { | ||
139 | |||
140 | // Fill the raw buffer if necessary. | ||
141 | if !first || parser.raw_buffer_pos == len(parser.raw_buffer) { | ||
142 | if !yaml_parser_update_raw_buffer(parser) { | ||
143 | parser.buffer = parser.buffer[:buffer_len] | ||
144 | return false | ||
145 | } | ||
146 | } | ||
147 | first = false | ||
148 | |||
149 | // Decode the raw buffer. | ||
150 | inner: | ||
151 | for parser.raw_buffer_pos != len(parser.raw_buffer) { | ||
152 | var value rune | ||
153 | var width int | ||
154 | |||
155 | raw_unread := len(parser.raw_buffer) - parser.raw_buffer_pos | ||
156 | |||
157 | // Decode the next character. | ||
158 | switch parser.encoding { | ||
159 | case yaml_UTF8_ENCODING: | ||
160 | // Decode a UTF-8 character. Check RFC 3629 | ||
161 | // (http://www.ietf.org/rfc/rfc3629.txt) for more details. | ||
162 | // | ||
163 | // The following table (taken from the RFC) is used for | ||
164 | // decoding. | ||
165 | // | ||
166 | // Char. number range | UTF-8 octet sequence | ||
167 | // (hexadecimal) | (binary) | ||
168 | // --------------------+------------------------------------ | ||
169 | // 0000 0000-0000 007F | 0xxxxxxx | ||
170 | // 0000 0080-0000 07FF | 110xxxxx 10xxxxxx | ||
171 | // 0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx | ||
172 | // 0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx | ||
173 | // | ||
174 | // Additionally, the characters in the range 0xD800-0xDFFF | ||
175 | // are prohibited as they are reserved for use with UTF-16 | ||
176 | // surrogate pairs. | ||
177 | |||
178 | // Determine the length of the UTF-8 sequence. | ||
179 | octet := parser.raw_buffer[parser.raw_buffer_pos] | ||
180 | switch { | ||
181 | case octet&0x80 == 0x00: | ||
182 | width = 1 | ||
183 | case octet&0xE0 == 0xC0: | ||
184 | width = 2 | ||
185 | case octet&0xF0 == 0xE0: | ||
186 | width = 3 | ||
187 | case octet&0xF8 == 0xF0: | ||
188 | width = 4 | ||
189 | default: | ||
190 | // The leading octet is invalid. | ||
191 | return yaml_parser_set_reader_error(parser, | ||
192 | "invalid leading UTF-8 octet", | ||
193 | parser.offset, int(octet)) | ||
194 | } | ||
195 | |||
196 | // Check if the raw buffer contains an incomplete character. | ||
197 | if width > raw_unread { | ||
198 | if parser.eof { | ||
199 | return yaml_parser_set_reader_error(parser, | ||
200 | "incomplete UTF-8 octet sequence", | ||
201 | parser.offset, -1) | ||
202 | } | ||
203 | break inner | ||
204 | } | ||
205 | |||
206 | // Decode the leading octet. | ||
207 | switch { | ||
208 | case octet&0x80 == 0x00: | ||
209 | value = rune(octet & 0x7F) | ||
210 | case octet&0xE0 == 0xC0: | ||
211 | value = rune(octet & 0x1F) | ||
212 | case octet&0xF0 == 0xE0: | ||
213 | value = rune(octet & 0x0F) | ||
214 | case octet&0xF8 == 0xF0: | ||
215 | value = rune(octet & 0x07) | ||
216 | default: | ||
217 | value = 0 | ||
218 | } | ||
219 | |||
220 | // Check and decode the trailing octets. | ||
221 | for k := 1; k < width; k++ { | ||
222 | octet = parser.raw_buffer[parser.raw_buffer_pos+k] | ||
223 | |||
224 | // Check if the octet is valid. | ||
225 | if (octet & 0xC0) != 0x80 { | ||
226 | return yaml_parser_set_reader_error(parser, | ||
227 | "invalid trailing UTF-8 octet", | ||
228 | parser.offset+k, int(octet)) | ||
229 | } | ||
230 | |||
231 | // Decode the octet. | ||
232 | value = (value << 6) + rune(octet&0x3F) | ||
233 | } | ||
234 | |||
235 | // Check the length of the sequence against the value. | ||
236 | switch { | ||
237 | case width == 1: | ||
238 | case width == 2 && value >= 0x80: | ||
239 | case width == 3 && value >= 0x800: | ||
240 | case width == 4 && value >= 0x10000: | ||
241 | default: | ||
242 | return yaml_parser_set_reader_error(parser, | ||
243 | "invalid length of a UTF-8 sequence", | ||
244 | parser.offset, -1) | ||
245 | } | ||
246 | |||
247 | // Check the range of the value. | ||
248 | if value >= 0xD800 && value <= 0xDFFF || value > 0x10FFFF { | ||
249 | return yaml_parser_set_reader_error(parser, | ||
250 | "invalid Unicode character", | ||
251 | parser.offset, int(value)) | ||
252 | } | ||
253 | |||
254 | case yaml_UTF16LE_ENCODING, yaml_UTF16BE_ENCODING: | ||
255 | var low, high int | ||
256 | if parser.encoding == yaml_UTF16LE_ENCODING { | ||
257 | low, high = 0, 1 | ||
258 | } else { | ||
259 | low, high = 1, 0 | ||
260 | } | ||
261 | |||
262 | // The UTF-16 encoding is not as simple as one might | ||
263 | // naively think. Check RFC 2781 | ||
264 | // (http://www.ietf.org/rfc/rfc2781.txt). | ||
265 | // | ||
266 | // Normally, two subsequent bytes describe a Unicode | ||
267 | // character. However a special technique (called a | ||
268 | // surrogate pair) is used for specifying character | ||
269 | // values larger than 0xFFFF. | ||
270 | // | ||
271 | // A surrogate pair consists of two pseudo-characters: | ||
272 | // high surrogate area (0xD800-0xDBFF) | ||
273 | // low surrogate area (0xDC00-0xDFFF) | ||
274 | // | ||
275 | // The following formulas are used for decoding | ||
276 | // and encoding characters using surrogate pairs: | ||
277 | // | ||
278 | // U = U' + 0x10000 (0x01 00 00 <= U <= 0x10 FF FF) | ||
279 | // U' = yyyyyyyyyyxxxxxxxxxx (0 <= U' <= 0x0F FF FF) | ||
280 | // W1 = 110110yyyyyyyyyy | ||
281 | // W2 = 110111xxxxxxxxxx | ||
282 | // | ||
283 | // where U is the character value, W1 is the high surrogate | ||
284 | // area, W2 is the low surrogate area. | ||
285 | |||
286 | // Check for incomplete UTF-16 character. | ||
287 | if raw_unread < 2 { | ||
288 | if parser.eof { | ||
289 | return yaml_parser_set_reader_error(parser, | ||
290 | "incomplete UTF-16 character", | ||
291 | parser.offset, -1) | ||
292 | } | ||
293 | break inner | ||
294 | } | ||
295 | |||
296 | // Get the character. | ||
297 | value = rune(parser.raw_buffer[parser.raw_buffer_pos+low]) + | ||
298 | (rune(parser.raw_buffer[parser.raw_buffer_pos+high]) << 8) | ||
299 | |||
300 | // Check for unexpected low surrogate area. | ||
301 | if value&0xFC00 == 0xDC00 { | ||
302 | return yaml_parser_set_reader_error(parser, | ||
303 | "unexpected low surrogate area", | ||
304 | parser.offset, int(value)) | ||
305 | } | ||
306 | |||
307 | // Check for a high surrogate area. | ||
308 | if value&0xFC00 == 0xD800 { | ||
309 | width = 4 | ||
310 | |||
311 | // Check for incomplete surrogate pair. | ||
312 | if raw_unread < 4 { | ||
313 | if parser.eof { | ||
314 | return yaml_parser_set_reader_error(parser, | ||
315 | "incomplete UTF-16 surrogate pair", | ||
316 | parser.offset, -1) | ||
317 | } | ||
318 | break inner | ||
319 | } | ||
320 | |||
321 | // Get the next character. | ||
322 | value2 := rune(parser.raw_buffer[parser.raw_buffer_pos+low+2]) + | ||
323 | (rune(parser.raw_buffer[parser.raw_buffer_pos+high+2]) << 8) | ||
324 | |||
325 | // Check for a low surrogate area. | ||
326 | if value2&0xFC00 != 0xDC00 { | ||
327 | return yaml_parser_set_reader_error(parser, | ||
328 | "expected low surrogate area", | ||
329 | parser.offset+2, int(value2)) | ||
330 | } | ||
331 | |||
332 | // Generate the value of the surrogate pair. | ||
333 | value = 0x10000 + ((value & 0x3FF) << 10) + (value2 & 0x3FF) | ||
334 | } else { | ||
335 | width = 2 | ||
336 | } | ||
337 | |||
338 | default: | ||
339 | panic("impossible") | ||
340 | } | ||
341 | |||
342 | // Check if the character is in the allowed range: | ||
343 | // #x9 | #xA | #xD | [#x20-#x7E] (8 bit) | ||
344 | // | #x85 | [#xA0-#xD7FF] | [#xE000-#xFFFD] (16 bit) | ||
345 | // | [#x10000-#x10FFFF] (32 bit) | ||
346 | switch { | ||
347 | case value == 0x09: | ||
348 | case value == 0x0A: | ||
349 | case value == 0x0D: | ||
350 | case value >= 0x20 && value <= 0x7E: | ||
351 | case value == 0x85: | ||
352 | case value >= 0xA0 && value <= 0xD7FF: | ||
353 | case value >= 0xE000 && value <= 0xFFFD: | ||
354 | case value >= 0x10000 && value <= 0x10FFFF: | ||
355 | default: | ||
356 | return yaml_parser_set_reader_error(parser, | ||
357 | "control characters are not allowed", | ||
358 | parser.offset, int(value)) | ||
359 | } | ||
360 | |||
361 | // Move the raw pointers. | ||
362 | parser.raw_buffer_pos += width | ||
363 | parser.offset += width | ||
364 | |||
365 | // Finally put the character into the buffer. | ||
366 | if value <= 0x7F { | ||
367 | // 0000 0000-0000 007F . 0xxxxxxx | ||
368 | parser.buffer[buffer_len+0] = byte(value) | ||
369 | buffer_len += 1 | ||
370 | } else if value <= 0x7FF { | ||
371 | // 0000 0080-0000 07FF . 110xxxxx 10xxxxxx | ||
372 | parser.buffer[buffer_len+0] = byte(0xC0 + (value >> 6)) | ||
373 | parser.buffer[buffer_len+1] = byte(0x80 + (value & 0x3F)) | ||
374 | buffer_len += 2 | ||
375 | } else if value <= 0xFFFF { | ||
376 | // 0000 0800-0000 FFFF . 1110xxxx 10xxxxxx 10xxxxxx | ||
377 | parser.buffer[buffer_len+0] = byte(0xE0 + (value >> 12)) | ||
378 | parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 6) & 0x3F)) | ||
379 | parser.buffer[buffer_len+2] = byte(0x80 + (value & 0x3F)) | ||
380 | buffer_len += 3 | ||
381 | } else { | ||
382 | // 0001 0000-0010 FFFF . 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx | ||
383 | parser.buffer[buffer_len+0] = byte(0xF0 + (value >> 18)) | ||
384 | parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 12) & 0x3F)) | ||
385 | parser.buffer[buffer_len+2] = byte(0x80 + ((value >> 6) & 0x3F)) | ||
386 | parser.buffer[buffer_len+3] = byte(0x80 + (value & 0x3F)) | ||
387 | buffer_len += 4 | ||
388 | } | ||
389 | |||
390 | parser.unread++ | ||
391 | } | ||
392 | |||
393 | // On EOF, put NUL into the buffer and return. | ||
394 | if parser.eof { | ||
395 | parser.buffer[buffer_len] = 0 | ||
396 | buffer_len++ | ||
397 | parser.unread++ | ||
398 | break | ||
399 | } | ||
400 | } | ||
401 | // [Go] Read the documentation of this function above. To return true, | ||
402 | // we need to have the given length in the buffer. Not doing that means | ||
403 | // every single check that calls this function to make sure the buffer | ||
404 | // has a given length is Go) panicking; or C) accessing invalid memory. | ||
405 | // This happens here due to the EOF above breaking early. | ||
406 | for buffer_len < length { | ||
407 | parser.buffer[buffer_len] = 0 | ||
408 | buffer_len++ | ||
409 | } | ||
410 | parser.buffer = parser.buffer[:buffer_len] | ||
411 | return true | ||
412 | } | ||