1 //===- llvm/unittest/Support/DataExtractorTest.cpp - DataExtractor tests --===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/Support/DataExtractor.h"
10 #include "llvm/Testing/Support/Error.h"
11 #include "gtest/gtest.h"
12 using namespace llvm;
13 
14 namespace {
15 
16 const char numberData[] = "\x80\x90\xFF\xFF\x80\x00\x00\x00";
17 const char leb128data[] = "\xA6\x49";
18 const char bigleb128data[] = "\xAA\xA9\xFF\xAA\xFF\xAA\xFF\x4A";
19 
20 TEST(DataExtractorTest, OffsetOverflow) {
21   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
22   EXPECT_FALSE(DE.isValidOffsetForDataOfSize(-2U, 5));
23 }
24 
25 TEST(DataExtractorTest, UnsignedNumbers) {
26   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
27   uint64_t offset = 0;
28 
29   EXPECT_EQ(0x80U, DE.getU8(&offset));
30   EXPECT_EQ(1U, offset);
31   offset = 0;
32   EXPECT_EQ(0x8090U, DE.getU16(&offset));
33   EXPECT_EQ(2U, offset);
34   offset = 0;
35   EXPECT_EQ(0x8090FFFFU, DE.getU32(&offset));
36   EXPECT_EQ(4U, offset);
37   offset = 0;
38   EXPECT_EQ(0x8090FFFF80000000ULL, DE.getU64(&offset));
39   EXPECT_EQ(8U, offset);
40   offset = 0;
41   EXPECT_EQ(0x8090FFFF80000000ULL, DE.getAddress(&offset));
42   EXPECT_EQ(8U, offset);
43   offset = 0;
44 
45   uint32_t data[2];
46   EXPECT_EQ(data, DE.getU32(&offset, data, 2));
47   EXPECT_EQ(0x8090FFFFU, data[0]);
48   EXPECT_EQ(0x80000000U, data[1]);
49   EXPECT_EQ(8U, offset);
50   offset = 0;
51 
52   // Now for little endian.
53   DE = DataExtractor(StringRef(numberData, sizeof(numberData)-1), true, 4);
54   EXPECT_EQ(0x9080U, DE.getU16(&offset));
55   EXPECT_EQ(2U, offset);
56   offset = 0;
57   EXPECT_EQ(0xFFFF9080U, DE.getU32(&offset));
58   EXPECT_EQ(4U, offset);
59   offset = 0;
60   EXPECT_EQ(0x80FFFF9080ULL, DE.getU64(&offset));
61   EXPECT_EQ(8U, offset);
62   offset = 0;
63   EXPECT_EQ(0xFFFF9080U, DE.getAddress(&offset));
64   EXPECT_EQ(4U, offset);
65   offset = 0;
66 
67   EXPECT_EQ(data, DE.getU32(&offset, data, 2));
68   EXPECT_EQ(0xFFFF9080U, data[0]);
69   EXPECT_EQ(0x80U, data[1]);
70   EXPECT_EQ(8U, offset);
71 }
72 
73 TEST(DataExtractorTest, SignedNumbers) {
74   DataExtractor DE(StringRef(numberData, sizeof(numberData)-1), false, 8);
75   uint64_t offset = 0;
76 
77   EXPECT_EQ(-128, DE.getSigned(&offset, 1));
78   EXPECT_EQ(1U, offset);
79   offset = 0;
80   EXPECT_EQ(-32624, DE.getSigned(&offset, 2));
81   EXPECT_EQ(2U, offset);
82   offset = 0;
83   EXPECT_EQ(-2137980929, DE.getSigned(&offset, 4));
84   EXPECT_EQ(4U, offset);
85   offset = 0;
86   EXPECT_EQ(-9182558167379214336LL, DE.getSigned(&offset, 8));
87   EXPECT_EQ(8U, offset);
88 }
89 
90 TEST(DataExtractorTest, Strings) {
91   const char stringData[] = "hellohello\0hello";
92   DataExtractor DE(StringRef(stringData, sizeof(stringData)-1), false, 8);
93   uint64_t offset = 0;
94 
95   EXPECT_EQ(stringData, DE.getCStr(&offset));
96   EXPECT_EQ(11U, offset);
97   EXPECT_EQ(nullptr, DE.getCStr(&offset));
98   EXPECT_EQ(11U, offset);
99 
100   DataExtractor::Cursor C(0);
101   EXPECT_EQ(stringData, DE.getCStr(C));
102   EXPECT_EQ(11U, C.tell());
103   EXPECT_EQ(nullptr, DE.getCStr(C));
104   EXPECT_EQ(11U, C.tell());
105   EXPECT_THAT_ERROR(C.takeError(),
106                     FailedWithMessage("unexpected end of data at offset 0xb"));
107 }
108 
109 TEST(DataExtractorTest, LEB128) {
110   DataExtractor DE(StringRef(leb128data, sizeof(leb128data)-1), false, 8);
111   uint64_t offset = 0;
112 
113   EXPECT_EQ(9382ULL, DE.getULEB128(&offset));
114   EXPECT_EQ(2U, offset);
115   offset = 0;
116   EXPECT_EQ(-7002LL, DE.getSLEB128(&offset));
117   EXPECT_EQ(2U, offset);
118 
119   DataExtractor BDE(StringRef(bigleb128data, sizeof(bigleb128data)-1), false,8);
120   offset = 0;
121   EXPECT_EQ(42218325750568106ULL, BDE.getULEB128(&offset));
122   EXPECT_EQ(8U, offset);
123   offset = 0;
124   EXPECT_EQ(-29839268287359830LL, BDE.getSLEB128(&offset));
125   EXPECT_EQ(8U, offset);
126 }
127 
128 TEST(DataExtractorTest, LEB128_error) {
129   DataExtractor DE(StringRef("\x81"), false, 8);
130   uint64_t Offset = 0;
131   EXPECT_EQ(0U, DE.getULEB128(&Offset));
132   EXPECT_EQ(0U, Offset);
133 
134   Offset = 0;
135   EXPECT_EQ(0U, DE.getSLEB128(&Offset));
136   EXPECT_EQ(0U, Offset);
137 
138   DataExtractor::Cursor C(0);
139   EXPECT_EQ(0U, DE.getULEB128(C));
140   EXPECT_THAT_ERROR(C.takeError(), Failed());
141 
142   C = DataExtractor::Cursor(0);
143   EXPECT_EQ(0U, DE.getSLEB128(C));
144   EXPECT_THAT_ERROR(C.takeError(), Failed());
145 }
146 
147 TEST(DataExtractorTest, Cursor_tell) {
148   DataExtractor DE(StringRef("AB"), false, 8);
149   DataExtractor::Cursor C(0);
150   // A successful read operation advances the cursor
151   EXPECT_EQ('A', DE.getU8(C));
152   EXPECT_EQ(1u, C.tell());
153 
154   // An unsuccessful one doesn't.
155   EXPECT_EQ(0u, DE.getU16(C));
156   EXPECT_EQ(1u, C.tell());
157 
158   // And neither do any subsequent operations.
159   EXPECT_EQ(0, DE.getU8(C));
160   EXPECT_EQ(1u, C.tell());
161 
162   consumeError(C.takeError());
163 }
164 
165 TEST(DataExtractorTest, Cursor_takeError) {
166   DataExtractor DE(StringRef("AB"), false, 8);
167   DataExtractor::Cursor C(0);
168   // Initially, the cursor is in the "success" state.
169   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
170 
171   // It remains "success" after a successful read.
172   EXPECT_EQ('A', DE.getU8(C));
173   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
174 
175   // An unsuccessful read sets the error state.
176   EXPECT_EQ(0u, DE.getU32(C));
177   EXPECT_THAT_ERROR(C.takeError(), Failed());
178 
179   // Once set the error sticks until explicitly cleared.
180   EXPECT_EQ(0u, DE.getU32(C));
181   EXPECT_EQ(0, DE.getU8(C));
182   EXPECT_THAT_ERROR(C.takeError(), Failed());
183 
184   // At which point reads can be succeed again.
185   EXPECT_EQ('B', DE.getU8(C));
186   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
187 }
188 
189 TEST(DataExtractorTest, Cursor_chaining) {
190   DataExtractor DE(StringRef("ABCD"), false, 8);
191   DataExtractor::Cursor C(0);
192 
193   // Multiple reads can be chained without trigerring any assertions.
194   EXPECT_EQ('A', DE.getU8(C));
195   EXPECT_EQ('B', DE.getU8(C));
196   EXPECT_EQ('C', DE.getU8(C));
197   EXPECT_EQ('D', DE.getU8(C));
198   // And the error checked at the end.
199   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
200 }
201 
202 #if defined(GTEST_HAS_DEATH_TEST) && defined(_DEBUG)
203 TEST(DataExtractorDeathTest, Cursor) {
204   DataExtractor DE(StringRef("AB"), false, 8);
205 
206   // Even an unused cursor must be checked for errors:
207   EXPECT_DEATH(DataExtractor::Cursor(0),
208                "Success values must still be checked prior to being destroyed");
209 
210   {
211     auto C = std::make_unique<DataExtractor::Cursor>(0);
212     EXPECT_EQ(0u, DE.getU32(*C));
213     // It must also be checked after an unsuccessful operation.
214     // destruction.
215     EXPECT_DEATH(C.reset(), "unexpected end of data");
216     EXPECT_THAT_ERROR(C->takeError(), Failed());
217   }
218   {
219     auto C = std::make_unique<DataExtractor::Cursor>(0);
220     EXPECT_EQ('A', DE.getU8(*C));
221     // Same goes for a successful one.
222     EXPECT_DEATH(
223         C.reset(),
224         "Success values must still be checked prior to being destroyed");
225     EXPECT_THAT_ERROR(C->takeError(), Succeeded());
226   }
227   {
228     auto C = std::make_unique<DataExtractor::Cursor>(0);
229     EXPECT_EQ('A', DE.getU8(*C));
230     EXPECT_EQ(0u, DE.getU32(*C));
231     // Even if a successful operation is followed by an unsuccessful one.
232     EXPECT_DEATH(C.reset(), "unexpected end of data");
233     EXPECT_THAT_ERROR(C->takeError(), Failed());
234   }
235   {
236     auto C = std::make_unique<DataExtractor::Cursor>(0);
237     EXPECT_EQ(0u, DE.getU32(*C));
238     EXPECT_EQ(0, DE.getU8(*C));
239     // Even if an unsuccessful operation is followed by one that would normally
240     // succeed.
241     EXPECT_DEATH(C.reset(), "unexpected end of data");
242     EXPECT_THAT_ERROR(C->takeError(), Failed());
243   }
244 }
245 #endif
246 
247 TEST(DataExtractorTest, getU8_vector) {
248   DataExtractor DE(StringRef("AB"), false, 8);
249   DataExtractor::Cursor C(0);
250   SmallVector<uint8_t, 2> S;
251 
252   DE.getU8(C, S, 4);
253   EXPECT_THAT_ERROR(C.takeError(), Failed());
254   EXPECT_EQ("", toStringRef(S));
255 
256   DE.getU8(C, S, 2);
257   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
258   EXPECT_EQ("AB", toStringRef(S));
259 }
260 
261 TEST(DataExtractorTest, getU24) {
262   DataExtractor DE(StringRef("ABCD"), false, 8);
263   DataExtractor::Cursor C(0);
264 
265   EXPECT_EQ(0x414243u, DE.getU24(C));
266   EXPECT_EQ(0u, DE.getU24(C));
267   EXPECT_EQ(3u, C.tell());
268   EXPECT_THAT_ERROR(C.takeError(), Failed());
269 }
270 
271 TEST(DataExtractorTest, skip) {
272   DataExtractor DE(StringRef("AB"), false, 8);
273   DataExtractor::Cursor C(0);
274 
275   DE.skip(C, 4);
276   EXPECT_THAT_ERROR(C.takeError(), Failed());
277   EXPECT_EQ(0u, C.tell());
278 
279   DE.skip(C, 2);
280   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
281   EXPECT_EQ(2u, C.tell());
282 }
283 
284 TEST(DataExtractorTest, eof) {
285   DataExtractor DE(StringRef("A"), false, 8);
286   DataExtractor::Cursor C(0);
287 
288   EXPECT_FALSE(DE.eof(C));
289 
290   EXPECT_EQ(0, DE.getU16(C));
291   EXPECT_FALSE(DE.eof(C));
292   EXPECT_THAT_ERROR(C.takeError(), Failed());
293 
294   EXPECT_EQ('A', DE.getU8(C));
295   EXPECT_TRUE(DE.eof(C));
296   EXPECT_THAT_ERROR(C.takeError(), Succeeded());
297 }
298 
299 TEST(DataExtractorTest, size) {
300   uint8_t Data[] = {'A', 'B', 'C', 'D'};
301   DataExtractor DE1(StringRef(reinterpret_cast<char *>(Data), sizeof(Data)),
302                     false, 8);
303   EXPECT_EQ(DE1.size(), sizeof(Data));
304   DataExtractor DE2(ArrayRef<uint8_t>(Data), false, 8);
305   EXPECT_EQ(DE2.size(), sizeof(Data));
306 }
307 
308 TEST(DataExtractorTest, FixedLengthString) {
309   const char Data[] = "hello\x00\x00\x00world  \thola\x00";
310   DataExtractor DE(StringRef(Data, sizeof(Data)-1), false, 8);
311   uint64_t Offset = 0;
312   StringRef Str;
313   // Test extracting too many bytes doesn't modify Offset and returns None.
314   Str = DE.getFixedLengthString(&Offset, sizeof(Data));
315   EXPECT_TRUE(Str.empty());
316   EXPECT_EQ(Offset, 0u);
317 
318   // Test extracting a fixed width C string with trailing NULL characters.
319   Str = DE.getFixedLengthString(&Offset, 8);
320   EXPECT_EQ(Offset, 8u);
321   EXPECT_EQ(Str.size(), 5u);
322   EXPECT_EQ(Str, "hello");
323   // Test extracting a fixed width C string with trailing space and tab
324   // characters.
325   Str = DE.getFixedLengthString(&Offset, 8, " \t");
326   EXPECT_EQ(Offset, 16u);
327   EXPECT_EQ(Str.size(), 5u);
328   EXPECT_EQ(Str, "world");
329   // Now extract a normal C string.
330   Str = DE.getCStrRef(&Offset);
331   EXPECT_EQ(Str.size(), 4u);
332   EXPECT_EQ(Str, "hola");
333 }
334 
335 
336 TEST(DataExtractorTest, GetBytes) {
337   // Use data with an embedded NULL character for good measure.
338   const char Data[] = "\x01\x02\x00\x04";
339   StringRef Bytes(Data, sizeof(Data)-1);
340   DataExtractor DE(Bytes, false, 8);
341   uint64_t Offset = 0;
342   StringRef Str;
343   // Test extracting too many bytes doesn't modify Offset and returns None.
344   Str = DE.getBytes(&Offset, sizeof(Data));
345   EXPECT_TRUE(Str.empty());
346   EXPECT_EQ(Offset, 0u);
347   // Test extracting 4 bytes from the stream.
348   Str = DE.getBytes(&Offset, 4);
349   EXPECT_EQ(Offset, 4u);
350   EXPECT_EQ(Str.size(), 4u);
351   EXPECT_EQ(Str, Bytes);
352 
353   DataExtractor::Cursor C(0);
354   EXPECT_EQ(StringRef("\x01\x02"), DE.getBytes(C, 2));
355   EXPECT_EQ(StringRef("\x00\x04", 2), DE.getBytes(C, 2));
356   EXPECT_EQ(StringRef(), DE.getBytes(C, 2));
357   EXPECT_EQ(StringRef(), DE.getBytes(C, 2));
358   EXPECT_EQ(4u, C.tell());
359   EXPECT_THAT_ERROR(C.takeError(), Failed());
360 }
361 
362 }
363