/rust/registry/src/index.crates.io-6f17d22bba15001f/leb128-0.2.5/src/lib.rs
Line | Count | Source (jump to first uncovered line) |
1 | | //! Read and write DWARF's "Little Endian Base 128" (LEB128) variable length |
2 | | //! integer encoding. |
3 | | //! |
4 | | //! The implementation is a direct translation of the psuedocode in the DWARF 4 |
5 | | //! standard's appendix C. |
6 | | //! |
7 | | //! Read and write signed integers: |
8 | | //! |
9 | | //! ``` |
10 | | //! use leb128; |
11 | | //! |
12 | | //! let mut buf = [0; 1024]; |
13 | | //! |
14 | | //! // Write to anything that implements `std::io::Write`. |
15 | | //! { |
16 | | //! let mut writable = &mut buf[..]; |
17 | | //! leb128::write::signed(&mut writable, -12345).expect("Should write number"); |
18 | | //! } |
19 | | //! |
20 | | //! // Read from anything that implements `std::io::Read`. |
21 | | //! let mut readable = &buf[..]; |
22 | | //! let val = leb128::read::signed(&mut readable).expect("Should read number"); |
23 | | //! assert_eq!(val, -12345); |
24 | | //! ``` |
25 | | //! |
26 | | //! Or read and write unsigned integers: |
27 | | //! |
28 | | //! ``` |
29 | | //! use leb128; |
30 | | //! |
31 | | //! let mut buf = [0; 1024]; |
32 | | //! |
33 | | //! { |
34 | | //! let mut writable = &mut buf[..]; |
35 | | //! leb128::write::unsigned(&mut writable, 98765).expect("Should write number"); |
36 | | //! } |
37 | | //! |
38 | | //! let mut readable = &buf[..]; |
39 | | //! let val = leb128::read::unsigned(&mut readable).expect("Should read number"); |
40 | | //! assert_eq!(val, 98765); |
41 | | //! ``` |
42 | | |
43 | | #![deny(missing_docs)] |
44 | | |
45 | | #[doc(hidden)] |
46 | | pub const CONTINUATION_BIT: u8 = 1 << 7; |
47 | | #[doc(hidden)] |
48 | | pub const SIGN_BIT: u8 = 1 << 6; |
49 | | |
50 | | #[doc(hidden)] |
51 | | #[inline] |
52 | 7.68M | pub fn low_bits_of_byte(byte: u8) -> u8 { |
53 | 7.68M | byte & !CONTINUATION_BIT |
54 | 7.68M | } Unexecuted instantiation: leb128::low_bits_of_byte Unexecuted instantiation: leb128::low_bits_of_byte Line | Count | Source | 52 | 7.68M | pub fn low_bits_of_byte(byte: u8) -> u8 { | 53 | 7.68M | byte & !CONTINUATION_BIT | 54 | 7.68M | } |
|
55 | | |
56 | | #[doc(hidden)] |
57 | | #[inline] |
58 | 7.68M | pub fn low_bits_of_u64(val: u64) -> u8 { |
59 | 7.68M | let byte = val & (std::u8::MAX as u64); |
60 | 7.68M | low_bits_of_byte(byte as u8) |
61 | 7.68M | } Unexecuted instantiation: leb128::low_bits_of_u64 Unexecuted instantiation: leb128::low_bits_of_u64 Line | Count | Source | 58 | 7.68M | pub fn low_bits_of_u64(val: u64) -> u8 { | 59 | 7.68M | let byte = val & (std::u8::MAX as u64); | 60 | 7.68M | low_bits_of_byte(byte as u8) | 61 | 7.68M | } |
|
62 | | |
63 | | /// A module for reading LEB128-encoded signed and unsigned integers. |
64 | | pub mod read { |
65 | | use super::{low_bits_of_byte, CONTINUATION_BIT, SIGN_BIT}; |
66 | | use std::fmt; |
67 | | use std::io; |
68 | | |
69 | | /// An error type for reading LEB128-encoded values. |
70 | | #[derive(Debug)] |
71 | | pub enum Error { |
72 | | /// There was an underlying IO error. |
73 | | IoError(io::Error), |
74 | | /// The number being read is larger than can be represented. |
75 | | Overflow, |
76 | | } |
77 | | |
78 | | impl From<io::Error> for Error { |
79 | | fn from(e: io::Error) -> Self { |
80 | | Error::IoError(e) |
81 | | } |
82 | | } |
83 | | |
84 | | impl fmt::Display for Error { |
85 | | fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> { |
86 | | match *self { |
87 | | Error::IoError(ref e) => e.fmt(f), |
88 | | Error::Overflow => { |
89 | | write!(f, "The number being read is larger than can be represented") |
90 | | } |
91 | | } |
92 | | } |
93 | | } |
94 | | |
95 | | impl std::error::Error for Error { |
96 | | fn source(&self) -> Option<&(dyn std::error::Error + 'static)> { |
97 | | match *self { |
98 | | Error::IoError(ref e) => Some(e), |
99 | | Error::Overflow => None, |
100 | | } |
101 | | } |
102 | | } |
103 | | |
104 | | /// Read an unsigned LEB128-encoded number from the `std::io::Read` stream |
105 | | /// `r`. |
106 | | /// |
107 | | /// On success, return the number. |
108 | | pub fn unsigned<R>(r: &mut R) -> Result<u64, Error> |
109 | | where |
110 | | R: ?Sized + io::Read, |
111 | | { |
112 | | let mut result = 0; |
113 | | let mut shift = 0; |
114 | | |
115 | | loop { |
116 | | let mut buf = [0]; |
117 | | r.read_exact(&mut buf)?; |
118 | | |
119 | | if shift == 63 && buf[0] != 0x00 && buf[0] != 0x01 { |
120 | | while buf[0] & CONTINUATION_BIT != 0 { |
121 | | r.read_exact(&mut buf)?; |
122 | | } |
123 | | return Err(Error::Overflow); |
124 | | } |
125 | | |
126 | | let low_bits = low_bits_of_byte(buf[0]) as u64; |
127 | | result |= low_bits << shift; |
128 | | |
129 | | if buf[0] & CONTINUATION_BIT == 0 { |
130 | | return Ok(result); |
131 | | } |
132 | | |
133 | | shift += 7; |
134 | | } |
135 | | } |
136 | | |
137 | | /// Read a signed LEB128-encoded number from the `std::io::Read` stream `r`. |
138 | | /// |
139 | | /// On success, return the number. |
140 | | pub fn signed<R>(r: &mut R) -> Result<i64, Error> |
141 | | where |
142 | | R: ?Sized + io::Read, |
143 | | { |
144 | | let mut result = 0; |
145 | | let mut shift = 0; |
146 | | let size = 64; |
147 | | let mut byte; |
148 | | |
149 | | loop { |
150 | | let mut buf = [0]; |
151 | | r.read_exact(&mut buf)?; |
152 | | |
153 | | byte = buf[0]; |
154 | | if shift == 63 && byte != 0x00 && byte != 0x7f { |
155 | | while buf[0] & CONTINUATION_BIT != 0 { |
156 | | r.read_exact(&mut buf)?; |
157 | | } |
158 | | return Err(Error::Overflow); |
159 | | } |
160 | | |
161 | | let low_bits = low_bits_of_byte(byte) as i64; |
162 | | result |= low_bits << shift; |
163 | | shift += 7; |
164 | | |
165 | | if byte & CONTINUATION_BIT == 0 { |
166 | | break; |
167 | | } |
168 | | } |
169 | | |
170 | | if shift < size && (SIGN_BIT & byte) == SIGN_BIT { |
171 | | // Sign extend the result. |
172 | | result |= !0 << shift; |
173 | | } |
174 | | |
175 | | Ok(result) |
176 | | } |
177 | | } |
178 | | |
179 | | /// A module for writing LEB128-encoded signed and unsigned integers. |
180 | | pub mod write { |
181 | | use super::{low_bits_of_u64, CONTINUATION_BIT}; |
182 | | use std::io; |
183 | | |
184 | | /// Write `val` to the `std::io::Write` stream `w` as an unsigned LEB128 value. |
185 | | /// |
186 | | /// On success, return the number of bytes written to `w`. |
187 | 6.38M | pub fn unsigned<W>(w: &mut W, mut val: u64) -> Result<usize, io::Error> |
188 | 6.38M | where |
189 | 6.38M | W: ?Sized + io::Write, |
190 | 6.38M | { |
191 | 6.38M | let mut bytes_written = 0; |
192 | 7.68M | loop { |
193 | 7.68M | let mut byte = low_bits_of_u64(val); |
194 | 7.68M | val >>= 7; |
195 | 7.68M | if val != 0 { |
196 | 1.30M | // More bytes to come, so set the continuation bit. |
197 | 1.30M | byte |= CONTINUATION_BIT; |
198 | 6.38M | } |
199 | | |
200 | 7.68M | let buf = [byte]; |
201 | 7.68M | w.write_all(&buf)?; |
202 | 7.68M | bytes_written += 1; |
203 | 7.68M | |
204 | 7.68M | if val == 0 { |
205 | 6.38M | return Ok(bytes_written); |
206 | 1.30M | } |
207 | | } |
208 | 6.38M | } Unexecuted instantiation: leb128::write::unsigned::<alloc::vec::Vec<u8>> Unexecuted instantiation: leb128::write::unsigned::<&mut [u8]> Unexecuted instantiation: leb128::write::unsigned::<alloc::vec::Vec<u8>> Unexecuted instantiation: leb128::write::unsigned::<&mut [u8]> leb128::write::unsigned::<&mut [u8]> Line | Count | Source | 187 | 6.38M | pub fn unsigned<W>(w: &mut W, mut val: u64) -> Result<usize, io::Error> | 188 | 6.38M | where | 189 | 6.38M | W: ?Sized + io::Write, | 190 | 6.38M | { | 191 | 6.38M | let mut bytes_written = 0; | 192 | 7.68M | loop { | 193 | 7.68M | let mut byte = low_bits_of_u64(val); | 194 | 7.68M | val >>= 7; | 195 | 7.68M | if val != 0 { | 196 | 1.30M | // More bytes to come, so set the continuation bit. | 197 | 1.30M | byte |= CONTINUATION_BIT; | 198 | 6.38M | } | 199 | | | 200 | 7.68M | let buf = [byte]; | 201 | 7.68M | w.write_all(&buf)?; | 202 | 7.68M | bytes_written += 1; | 203 | 7.68M | | 204 | 7.68M | if val == 0 { | 205 | 6.38M | return Ok(bytes_written); | 206 | 1.30M | } | 207 | | } | 208 | 6.38M | } |
|
209 | | |
210 | | /// Write `val` to the `std::io::Write` stream `w` as a signed LEB128 value. |
211 | | /// |
212 | | /// On success, return the number of bytes written to `w`. |
213 | 674k | pub fn signed<W>(w: &mut W, mut val: i64) -> Result<usize, io::Error> |
214 | 674k | where |
215 | 674k | W: ?Sized + io::Write, |
216 | 674k | { |
217 | 674k | let mut bytes_written = 0; |
218 | 4.22M | loop { |
219 | 4.22M | let mut byte = val as u8; |
220 | 4.22M | // Keep the sign bit for testing |
221 | 4.22M | val >>= 6; |
222 | 4.22M | let done = val == 0 || val == -1; |
223 | 4.22M | if done { |
224 | 674k | byte &= !CONTINUATION_BIT; |
225 | 3.55M | } else { |
226 | 3.55M | // Remove the sign bit |
227 | 3.55M | val >>= 1; |
228 | 3.55M | // More bytes to come, so set the continuation bit. |
229 | 3.55M | byte |= CONTINUATION_BIT; |
230 | 3.55M | } |
231 | | |
232 | 4.22M | let buf = [byte]; |
233 | 4.22M | w.write_all(&buf)?; |
234 | 4.22M | bytes_written += 1; |
235 | 4.22M | |
236 | 4.22M | if done { |
237 | 674k | return Ok(bytes_written); |
238 | 3.55M | } |
239 | | } |
240 | 674k | } Unexecuted instantiation: leb128::write::signed::<alloc::vec::Vec<u8>> Unexecuted instantiation: leb128::write::signed::<alloc::vec::Vec<u8>> leb128::write::signed::<&mut [u8]> Line | Count | Source | 213 | 674k | pub fn signed<W>(w: &mut W, mut val: i64) -> Result<usize, io::Error> | 214 | 674k | where | 215 | 674k | W: ?Sized + io::Write, | 216 | 674k | { | 217 | 674k | let mut bytes_written = 0; | 218 | 4.22M | loop { | 219 | 4.22M | let mut byte = val as u8; | 220 | 4.22M | // Keep the sign bit for testing | 221 | 4.22M | val >>= 6; | 222 | 4.22M | let done = val == 0 || val == -1; | 223 | 4.22M | if done { | 224 | 674k | byte &= !CONTINUATION_BIT; | 225 | 3.55M | } else { | 226 | 3.55M | // Remove the sign bit | 227 | 3.55M | val >>= 1; | 228 | 3.55M | // More bytes to come, so set the continuation bit. | 229 | 3.55M | byte |= CONTINUATION_BIT; | 230 | 3.55M | } | 231 | | | 232 | 4.22M | let buf = [byte]; | 233 | 4.22M | w.write_all(&buf)?; | 234 | 4.22M | bytes_written += 1; | 235 | 4.22M | | 236 | 4.22M | if done { | 237 | 674k | return Ok(bytes_written); | 238 | 3.55M | } | 239 | | } | 240 | 674k | } |
|
241 | | } |
242 | | |
243 | | #[cfg(test)] |
244 | | mod tests { |
245 | | use super::*; |
246 | | use std; |
247 | | use std::io; |
248 | | |
249 | | #[test] |
250 | | fn test_low_bits_of_byte() { |
251 | | for i in 0..127 { |
252 | | assert_eq!(i, low_bits_of_byte(i)); |
253 | | assert_eq!(i, low_bits_of_byte(i | CONTINUATION_BIT)); |
254 | | } |
255 | | } |
256 | | |
257 | | #[test] |
258 | | fn test_low_bits_of_u64() { |
259 | | for i in 0u64..127 { |
260 | | assert_eq!(i as u8, low_bits_of_u64(1 << 16 | i)); |
261 | | assert_eq!( |
262 | | i as u8, |
263 | | low_bits_of_u64(i << 16 | i | (CONTINUATION_BIT as u64)) |
264 | | ); |
265 | | } |
266 | | } |
267 | | |
268 | | // Examples from the DWARF 4 standard, section 7.6, figure 22. |
269 | | #[test] |
270 | | fn test_read_unsigned() { |
271 | | let buf = [2u8]; |
272 | | let mut readable = &buf[..]; |
273 | | assert_eq!( |
274 | | 2, |
275 | | read::unsigned(&mut readable).expect("Should read number") |
276 | | ); |
277 | | |
278 | | let buf = [127u8]; |
279 | | let mut readable = &buf[..]; |
280 | | assert_eq!( |
281 | | 127, |
282 | | read::unsigned(&mut readable).expect("Should read number") |
283 | | ); |
284 | | |
285 | | let buf = [CONTINUATION_BIT, 1]; |
286 | | let mut readable = &buf[..]; |
287 | | assert_eq!( |
288 | | 128, |
289 | | read::unsigned(&mut readable).expect("Should read number") |
290 | | ); |
291 | | |
292 | | let buf = [1u8 | CONTINUATION_BIT, 1]; |
293 | | let mut readable = &buf[..]; |
294 | | assert_eq!( |
295 | | 129, |
296 | | read::unsigned(&mut readable).expect("Should read number") |
297 | | ); |
298 | | |
299 | | let buf = [2u8 | CONTINUATION_BIT, 1]; |
300 | | let mut readable = &buf[..]; |
301 | | assert_eq!( |
302 | | 130, |
303 | | read::unsigned(&mut readable).expect("Should read number") |
304 | | ); |
305 | | |
306 | | let buf = [57u8 | CONTINUATION_BIT, 100]; |
307 | | let mut readable = &buf[..]; |
308 | | assert_eq!( |
309 | | 12857, |
310 | | read::unsigned(&mut readable).expect("Should read number") |
311 | | ); |
312 | | } |
313 | | |
314 | | #[test] |
315 | | fn test_read_unsigned_thru_dyn_trait() { |
316 | | fn read(r: &mut dyn io::Read) -> u64 { |
317 | | read::unsigned(r).expect("Should read number") |
318 | | } |
319 | | |
320 | | let buf = [0u8]; |
321 | | |
322 | | let mut readable = &buf[..]; |
323 | | assert_eq!(0, read(&mut readable)); |
324 | | |
325 | | let mut readable = io::Cursor::new(buf); |
326 | | assert_eq!(0, read(&mut readable)); |
327 | | } |
328 | | |
329 | | // Examples from the DWARF 4 standard, section 7.6, figure 23. |
330 | | #[test] |
331 | | fn test_read_signed() { |
332 | | let buf = [2u8]; |
333 | | let mut readable = &buf[..]; |
334 | | assert_eq!(2, read::signed(&mut readable).expect("Should read number")); |
335 | | |
336 | | let buf = [0x7eu8]; |
337 | | let mut readable = &buf[..]; |
338 | | assert_eq!(-2, read::signed(&mut readable).expect("Should read number")); |
339 | | |
340 | | let buf = [127u8 | CONTINUATION_BIT, 0]; |
341 | | let mut readable = &buf[..]; |
342 | | assert_eq!( |
343 | | 127, |
344 | | read::signed(&mut readable).expect("Should read number") |
345 | | ); |
346 | | |
347 | | let buf = [1u8 | CONTINUATION_BIT, 0x7f]; |
348 | | let mut readable = &buf[..]; |
349 | | assert_eq!( |
350 | | -127, |
351 | | read::signed(&mut readable).expect("Should read number") |
352 | | ); |
353 | | |
354 | | let buf = [CONTINUATION_BIT, 1]; |
355 | | let mut readable = &buf[..]; |
356 | | assert_eq!( |
357 | | 128, |
358 | | read::signed(&mut readable).expect("Should read number") |
359 | | ); |
360 | | |
361 | | let buf = [CONTINUATION_BIT, 0x7f]; |
362 | | let mut readable = &buf[..]; |
363 | | assert_eq!( |
364 | | -128, |
365 | | read::signed(&mut readable).expect("Should read number") |
366 | | ); |
367 | | |
368 | | let buf = [1u8 | CONTINUATION_BIT, 1]; |
369 | | let mut readable = &buf[..]; |
370 | | assert_eq!( |
371 | | 129, |
372 | | read::signed(&mut readable).expect("Should read number") |
373 | | ); |
374 | | |
375 | | let buf = [0x7fu8 | CONTINUATION_BIT, 0x7e]; |
376 | | let mut readable = &buf[..]; |
377 | | assert_eq!( |
378 | | -129, |
379 | | read::signed(&mut readable).expect("Should read number") |
380 | | ); |
381 | | } |
382 | | |
383 | | #[test] |
384 | | fn test_read_signed_thru_dyn_trait() { |
385 | | fn read(r: &mut dyn io::Read) -> i64 { |
386 | | read::signed(r).expect("Should read number") |
387 | | } |
388 | | |
389 | | let buf = [0u8]; |
390 | | |
391 | | let mut readable = &buf[..]; |
392 | | assert_eq!(0, read(&mut readable)); |
393 | | |
394 | | let mut readable = io::Cursor::new(buf); |
395 | | assert_eq!(0, read(&mut readable)); |
396 | | } |
397 | | |
398 | | #[test] |
399 | | fn test_read_signed_63_bits() { |
400 | | let buf = [ |
401 | | CONTINUATION_BIT, |
402 | | CONTINUATION_BIT, |
403 | | CONTINUATION_BIT, |
404 | | CONTINUATION_BIT, |
405 | | CONTINUATION_BIT, |
406 | | CONTINUATION_BIT, |
407 | | CONTINUATION_BIT, |
408 | | CONTINUATION_BIT, |
409 | | 0x40, |
410 | | ]; |
411 | | let mut readable = &buf[..]; |
412 | | assert_eq!( |
413 | | -0x4000000000000000, |
414 | | read::signed(&mut readable).expect("Should read number") |
415 | | ); |
416 | | } |
417 | | |
418 | | #[test] |
419 | | fn test_read_unsigned_not_enough_data() { |
420 | | let buf = [CONTINUATION_BIT]; |
421 | | let mut readable = &buf[..]; |
422 | | match read::unsigned(&mut readable) { |
423 | | Err(read::Error::IoError(e)) => assert_eq!(e.kind(), io::ErrorKind::UnexpectedEof), |
424 | | otherwise => panic!("Unexpected: {:?}", otherwise), |
425 | | } |
426 | | } |
427 | | |
428 | | #[test] |
429 | | fn test_read_signed_not_enough_data() { |
430 | | let buf = [CONTINUATION_BIT]; |
431 | | let mut readable = &buf[..]; |
432 | | match read::signed(&mut readable) { |
433 | | Err(read::Error::IoError(e)) => assert_eq!(e.kind(), io::ErrorKind::UnexpectedEof), |
434 | | otherwise => panic!("Unexpected: {:?}", otherwise), |
435 | | } |
436 | | } |
437 | | |
438 | | #[test] |
439 | | fn test_write_unsigned_not_enough_space() { |
440 | | let mut buf = [0; 1]; |
441 | | let mut writable = &mut buf[..]; |
442 | | match write::unsigned(&mut writable, 128) { |
443 | | Err(e) => assert_eq!(e.kind(), io::ErrorKind::WriteZero), |
444 | | otherwise => panic!("Unexpected: {:?}", otherwise), |
445 | | } |
446 | | } |
447 | | |
448 | | #[test] |
449 | | fn test_write_signed_not_enough_space() { |
450 | | let mut buf = [0; 1]; |
451 | | let mut writable = &mut buf[..]; |
452 | | match write::signed(&mut writable, 128) { |
453 | | Err(e) => assert_eq!(e.kind(), io::ErrorKind::WriteZero), |
454 | | otherwise => panic!("Unexpected: {:?}", otherwise), |
455 | | } |
456 | | } |
457 | | |
458 | | #[test] |
459 | | fn test_write_unsigned_thru_dyn_trait() { |
460 | | fn write(w: &mut dyn io::Write, val: u64) -> usize { |
461 | | write::unsigned(w, val).expect("Should write number") |
462 | | } |
463 | | let mut buf = [0u8; 1]; |
464 | | |
465 | | let mut writable = &mut buf[..]; |
466 | | assert_eq!(write(&mut writable, 0), 1); |
467 | | assert_eq!(buf[0], 0); |
468 | | |
469 | | let mut writable = Vec::from(&buf[..]); |
470 | | assert_eq!(write(&mut writable, 0), 1); |
471 | | assert_eq!(buf[0], 0); |
472 | | } |
473 | | |
474 | | #[test] |
475 | | fn test_write_signed_thru_dyn_trait() { |
476 | | fn write(w: &mut dyn io::Write, val: i64) -> usize { |
477 | | write::signed(w, val).expect("Should write number") |
478 | | } |
479 | | let mut buf = [0u8; 1]; |
480 | | |
481 | | let mut writable = &mut buf[..]; |
482 | | assert_eq!(write(&mut writable, 0), 1); |
483 | | assert_eq!(buf[0], 0); |
484 | | |
485 | | let mut writable = Vec::from(&buf[..]); |
486 | | assert_eq!(write(&mut writable, 0), 1); |
487 | | assert_eq!(buf[0], 0); |
488 | | } |
489 | | |
490 | | #[test] |
491 | | fn dogfood_signed() { |
492 | | fn inner(i: i64) { |
493 | | let mut buf = [0u8; 1024]; |
494 | | |
495 | | { |
496 | | let mut writable = &mut buf[..]; |
497 | | write::signed(&mut writable, i).expect("Should write signed number"); |
498 | | } |
499 | | |
500 | | let mut readable = &buf[..]; |
501 | | let result = read::signed(&mut readable).expect("Should be able to read it back again"); |
502 | | assert_eq!(i, result); |
503 | | } |
504 | | for i in -513..513 { |
505 | | inner(i); |
506 | | } |
507 | | inner(std::i64::MIN); |
508 | | } |
509 | | |
510 | | #[test] |
511 | | fn dogfood_unsigned() { |
512 | | for i in 0..1025 { |
513 | | let mut buf = [0u8; 1024]; |
514 | | |
515 | | { |
516 | | let mut writable = &mut buf[..]; |
517 | | write::unsigned(&mut writable, i).expect("Should write signed number"); |
518 | | } |
519 | | |
520 | | let mut readable = &buf[..]; |
521 | | let result = |
522 | | read::unsigned(&mut readable).expect("Should be able to read it back again"); |
523 | | assert_eq!(i, result); |
524 | | } |
525 | | } |
526 | | |
527 | | #[test] |
528 | | fn test_read_unsigned_overflow() { |
529 | | let buf = [ |
530 | | 2u8 | CONTINUATION_BIT, |
531 | | 2 | CONTINUATION_BIT, |
532 | | 2 | CONTINUATION_BIT, |
533 | | 2 | CONTINUATION_BIT, |
534 | | 2 | CONTINUATION_BIT, |
535 | | 2 | CONTINUATION_BIT, |
536 | | 2 | CONTINUATION_BIT, |
537 | | 2 | CONTINUATION_BIT, |
538 | | 2 | CONTINUATION_BIT, |
539 | | 2 | CONTINUATION_BIT, |
540 | | 2 | CONTINUATION_BIT, |
541 | | 2 | CONTINUATION_BIT, |
542 | | 2 | CONTINUATION_BIT, |
543 | | 2 | CONTINUATION_BIT, |
544 | | 2 | CONTINUATION_BIT, |
545 | | 2 | CONTINUATION_BIT, |
546 | | 2 | CONTINUATION_BIT, |
547 | | 2 | CONTINUATION_BIT, |
548 | | 2 | CONTINUATION_BIT, |
549 | | 2 | CONTINUATION_BIT, |
550 | | 2 | CONTINUATION_BIT, |
551 | | 2 | CONTINUATION_BIT, |
552 | | 2 | CONTINUATION_BIT, |
553 | | 2 | CONTINUATION_BIT, |
554 | | 2 | CONTINUATION_BIT, |
555 | | 2 | CONTINUATION_BIT, |
556 | | 2 | CONTINUATION_BIT, |
557 | | 2 | CONTINUATION_BIT, |
558 | | 2 | CONTINUATION_BIT, |
559 | | 2 | CONTINUATION_BIT, |
560 | | 1, |
561 | | ]; |
562 | | let mut readable = &buf[..]; |
563 | | assert!(read::unsigned(&mut readable).is_err()); |
564 | | } |
565 | | |
566 | | #[test] |
567 | | fn test_read_signed_overflow() { |
568 | | let buf = [ |
569 | | 2u8 | CONTINUATION_BIT, |
570 | | 2 | CONTINUATION_BIT, |
571 | | 2 | CONTINUATION_BIT, |
572 | | 2 | CONTINUATION_BIT, |
573 | | 2 | CONTINUATION_BIT, |
574 | | 2 | CONTINUATION_BIT, |
575 | | 2 | CONTINUATION_BIT, |
576 | | 2 | CONTINUATION_BIT, |
577 | | 2 | CONTINUATION_BIT, |
578 | | 2 | CONTINUATION_BIT, |
579 | | 2 | CONTINUATION_BIT, |
580 | | 2 | CONTINUATION_BIT, |
581 | | 2 | CONTINUATION_BIT, |
582 | | 2 | CONTINUATION_BIT, |
583 | | 2 | CONTINUATION_BIT, |
584 | | 2 | CONTINUATION_BIT, |
585 | | 2 | CONTINUATION_BIT, |
586 | | 2 | CONTINUATION_BIT, |
587 | | 2 | CONTINUATION_BIT, |
588 | | 2 | CONTINUATION_BIT, |
589 | | 2 | CONTINUATION_BIT, |
590 | | 2 | CONTINUATION_BIT, |
591 | | 2 | CONTINUATION_BIT, |
592 | | 2 | CONTINUATION_BIT, |
593 | | 2 | CONTINUATION_BIT, |
594 | | 2 | CONTINUATION_BIT, |
595 | | 2 | CONTINUATION_BIT, |
596 | | 2 | CONTINUATION_BIT, |
597 | | 2 | CONTINUATION_BIT, |
598 | | 2 | CONTINUATION_BIT, |
599 | | 1, |
600 | | ]; |
601 | | let mut readable = &buf[..]; |
602 | | assert!(read::signed(&mut readable).is_err()); |
603 | | } |
604 | | |
605 | | #[test] |
606 | | fn test_read_multiple() { |
607 | | let buf = [2u8 | CONTINUATION_BIT, 1u8, 1u8]; |
608 | | |
609 | | let mut readable = &buf[..]; |
610 | | assert_eq!( |
611 | | read::unsigned(&mut readable).expect("Should read first number"), |
612 | | 130u64 |
613 | | ); |
614 | | assert_eq!( |
615 | | read::unsigned(&mut readable).expect("Should read first number"), |
616 | | 1u64 |
617 | | ); |
618 | | } |
619 | | |
620 | | #[test] |
621 | | fn test_read_multiple_with_overflow() { |
622 | | let buf = [ |
623 | | 0b1111_1111, |
624 | | 0b1111_1111, |
625 | | 0b1111_1111, |
626 | | 0b1111_1111, |
627 | | 0b1111_1111, |
628 | | 0b1111_1111, |
629 | | 0b1111_1111, |
630 | | 0b1111_1111, |
631 | | 0b1111_1111, |
632 | | 0b1111_1111, |
633 | | 0b0111_1111, // Overflow! |
634 | | 0b1110_0100, |
635 | | 0b1110_0000, |
636 | | 0b0000_0010, // 45156 |
637 | | ]; |
638 | | let mut readable = &buf[..]; |
639 | | |
640 | | assert!(if let read::Error::Overflow = |
641 | | read::unsigned(&mut readable).expect_err("Should fail with Error::Overflow") |
642 | | { |
643 | | true |
644 | | } else { |
645 | | false |
646 | | }); |
647 | | assert_eq!( |
648 | | read::unsigned(&mut readable).expect("Should succeed with correct value"), |
649 | | 45156 |
650 | | ); |
651 | | } |
652 | | } |