1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * KUnit test for struct string_stream. 4 * 5 * Copyright (C) 2019, Google LLC. 6 * Author: Brendan Higgins <brendanhiggins@google.com> 7 */ 8 9 #include <kunit/static_stub.h> 10 #include <kunit/test.h> 11 #include <linux/ktime.h> 12 #include <linux/slab.h> 13 #include <linux/timekeeping.h> 14 15 #include "string-stream.h" 16 17 struct string_stream_test_priv { 18 /* For testing resource-managed free. */ 19 struct string_stream *expected_free_stream; 20 bool stream_was_freed; 21 bool stream_free_again; 22 }; 23 24 /* Avoids a cast warning if kfree() is passed direct to kunit_add_action(). */ 25 KUNIT_DEFINE_ACTION_WRAPPER(kfree_wrapper, kfree, const void *); 26 27 /* Avoids a cast warning if string_stream_destroy() is passed direct to kunit_add_action(). */ 28 KUNIT_DEFINE_ACTION_WRAPPER(cleanup_raw_stream, string_stream_destroy, struct string_stream *); 29 30 static char *get_concatenated_string(struct kunit *test, struct string_stream *stream) 31 { 32 char *str = string_stream_get_string(stream); 33 34 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, str); 35 kunit_add_action(test, kfree_wrapper, (void *)str); 36 37 return str; 38 } 39 40 /* Managed string_stream object is initialized correctly. */ 41 static void string_stream_managed_init_test(struct kunit *test) 42 { 43 struct string_stream *stream; 44 45 /* Resource-managed initialization. */ 46 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 47 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 48 49 KUNIT_EXPECT_EQ(test, stream->length, 0); 50 KUNIT_EXPECT_TRUE(test, list_empty(&stream->fragments)); 51 KUNIT_EXPECT_TRUE(test, (stream->gfp == GFP_KERNEL)); 52 KUNIT_EXPECT_FALSE(test, stream->append_newlines); 53 KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream)); 54 } 55 56 /* Unmanaged string_stream object is initialized correctly. */ 57 static void string_stream_unmanaged_init_test(struct kunit *test) 58 { 59 struct string_stream *stream; 60 61 stream = alloc_string_stream(GFP_KERNEL); 62 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 63 kunit_add_action(test, cleanup_raw_stream, stream); 64 65 KUNIT_EXPECT_EQ(test, stream->length, 0); 66 KUNIT_EXPECT_TRUE(test, list_empty(&stream->fragments)); 67 KUNIT_EXPECT_TRUE(test, (stream->gfp == GFP_KERNEL)); 68 KUNIT_EXPECT_FALSE(test, stream->append_newlines); 69 70 KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream)); 71 } 72 73 static void string_stream_destroy_stub(struct string_stream *stream) 74 { 75 struct kunit *fake_test = kunit_get_current_test(); 76 struct string_stream_test_priv *priv = fake_test->priv; 77 78 /* The kunit could own string_streams other than the one we are testing. */ 79 if (stream == priv->expected_free_stream) { 80 if (priv->stream_was_freed) 81 priv->stream_free_again = true; 82 else 83 priv->stream_was_freed = true; 84 } 85 86 /* 87 * Calling string_stream_destroy() will only call this function again 88 * because the redirection stub is still active. 89 * Avoid calling deactivate_static_stub() or changing current->kunit_test 90 * during cleanup. 91 */ 92 string_stream_clear(stream); 93 kfree(stream); 94 } 95 96 /* kunit_free_string_stream() calls string_stream_desrtoy() */ 97 static void string_stream_managed_free_test(struct kunit *test) 98 { 99 struct string_stream_test_priv *priv = test->priv; 100 101 priv->expected_free_stream = NULL; 102 priv->stream_was_freed = false; 103 priv->stream_free_again = false; 104 105 kunit_activate_static_stub(test, 106 string_stream_destroy, 107 string_stream_destroy_stub); 108 109 priv->expected_free_stream = kunit_alloc_string_stream(test, GFP_KERNEL); 110 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->expected_free_stream); 111 112 /* This should call the stub function. */ 113 kunit_free_string_stream(test, priv->expected_free_stream); 114 115 KUNIT_EXPECT_TRUE(test, priv->stream_was_freed); 116 KUNIT_EXPECT_FALSE(test, priv->stream_free_again); 117 } 118 119 /* string_stream object is freed when test is cleaned up. */ 120 static void string_stream_resource_free_test(struct kunit *test) 121 { 122 struct string_stream_test_priv *priv = test->priv; 123 struct kunit *fake_test; 124 125 fake_test = kunit_kzalloc(test, sizeof(*fake_test), GFP_KERNEL); 126 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_test); 127 128 kunit_init_test(fake_test, "string_stream_fake_test", NULL); 129 fake_test->priv = priv; 130 131 /* 132 * Activate stub before creating string_stream so the 133 * string_stream will be cleaned up first. 134 */ 135 priv->expected_free_stream = NULL; 136 priv->stream_was_freed = false; 137 priv->stream_free_again = false; 138 139 kunit_activate_static_stub(fake_test, 140 string_stream_destroy, 141 string_stream_destroy_stub); 142 143 priv->expected_free_stream = kunit_alloc_string_stream(fake_test, GFP_KERNEL); 144 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->expected_free_stream); 145 146 /* Set current->kunit_test to fake_test so the static stub will be called. */ 147 current->kunit_test = fake_test; 148 149 /* Cleanup test - the stub function should be called */ 150 kunit_cleanup(fake_test); 151 152 /* Set current->kunit_test back to current test. */ 153 current->kunit_test = test; 154 155 KUNIT_EXPECT_TRUE(test, priv->stream_was_freed); 156 KUNIT_EXPECT_FALSE(test, priv->stream_free_again); 157 } 158 159 /* 160 * Add a series of lines to a string_stream. Check that all lines 161 * appear in the correct order and no characters are dropped. 162 */ 163 static void string_stream_line_add_test(struct kunit *test) 164 { 165 struct string_stream *stream; 166 char line[60]; 167 char *concat_string, *pos, *string_end; 168 size_t len, total_len; 169 int num_lines, i; 170 171 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 172 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 173 174 /* Add series of sequence numbered lines */ 175 total_len = 0; 176 for (i = 0; i < 100; ++i) { 177 len = snprintf(line, sizeof(line), 178 "The quick brown fox jumps over the lazy penguin %d\n", i); 179 180 /* Sanity-check that our test string isn't truncated */ 181 KUNIT_ASSERT_LT(test, len, sizeof(line)); 182 183 string_stream_add(stream, line); 184 total_len += len; 185 } 186 num_lines = i; 187 188 concat_string = get_concatenated_string(test, stream); 189 KUNIT_EXPECT_NOT_ERR_OR_NULL(test, concat_string); 190 KUNIT_EXPECT_EQ(test, strlen(concat_string), total_len); 191 192 /* 193 * Split the concatenated string at the newlines and check that 194 * all the original added strings are present. 195 */ 196 pos = concat_string; 197 for (i = 0; i < num_lines; ++i) { 198 string_end = strchr(pos, '\n'); 199 KUNIT_EXPECT_NOT_NULL(test, string_end); 200 201 /* Convert to NULL-terminated string */ 202 *string_end = '\0'; 203 204 snprintf(line, sizeof(line), 205 "The quick brown fox jumps over the lazy penguin %d", i); 206 KUNIT_EXPECT_STREQ(test, pos, line); 207 208 pos = string_end + 1; 209 } 210 211 /* There shouldn't be any more data after this */ 212 KUNIT_EXPECT_EQ(test, strlen(pos), 0); 213 } 214 215 /* Add a series of lines of variable length to a string_stream. */ 216 static void string_stream_variable_length_line_test(struct kunit *test) 217 { 218 static const char line[] = 219 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" 220 " 0123456789!$%^&*()_-+={}[]:;@'~#<>,.?/|"; 221 struct string_stream *stream; 222 struct rnd_state rnd; 223 char *concat_string, *pos, *string_end; 224 size_t offset, total_len; 225 int num_lines, i; 226 227 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 228 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 229 230 /* 231 * Log many lines of varying lengths until we have created 232 * many fragments. 233 * The "randomness" must be repeatable. 234 */ 235 prandom_seed_state(&rnd, 3141592653589793238ULL); 236 total_len = 0; 237 for (i = 0; i < 100; ++i) { 238 offset = prandom_u32_state(&rnd) % (sizeof(line) - 1); 239 string_stream_add(stream, "%s\n", &line[offset]); 240 total_len += sizeof(line) - offset; 241 } 242 num_lines = i; 243 244 concat_string = get_concatenated_string(test, stream); 245 KUNIT_EXPECT_NOT_ERR_OR_NULL(test, concat_string); 246 KUNIT_EXPECT_EQ(test, strlen(concat_string), total_len); 247 248 /* 249 * Split the concatenated string at the newlines and check that 250 * all the original added strings are present. 251 */ 252 prandom_seed_state(&rnd, 3141592653589793238ULL); 253 pos = concat_string; 254 for (i = 0; i < num_lines; ++i) { 255 string_end = strchr(pos, '\n'); 256 KUNIT_EXPECT_NOT_NULL(test, string_end); 257 258 /* Convert to NULL-terminated string */ 259 *string_end = '\0'; 260 261 offset = prandom_u32_state(&rnd) % (sizeof(line) - 1); 262 KUNIT_EXPECT_STREQ(test, pos, &line[offset]); 263 264 pos = string_end + 1; 265 } 266 267 /* There shouldn't be any more data after this */ 268 KUNIT_EXPECT_EQ(test, strlen(pos), 0); 269 } 270 271 /* Appending the content of one string stream to another. */ 272 static void string_stream_append_test(struct kunit *test) 273 { 274 static const char * const strings_1[] = { 275 "one", "two", "three", "four", "five", "six", 276 "seven", "eight", "nine", "ten", 277 }; 278 static const char * const strings_2[] = { 279 "Apple", "Pear", "Orange", "Banana", "Grape", "Apricot", 280 }; 281 struct string_stream *stream_1, *stream_2; 282 const char *stream1_content_before_append, *stream_2_content; 283 char *combined_content; 284 size_t combined_length; 285 int i; 286 287 stream_1 = kunit_alloc_string_stream(test, GFP_KERNEL); 288 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_1); 289 290 stream_2 = kunit_alloc_string_stream(test, GFP_KERNEL); 291 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_2); 292 293 /* Append content of empty stream to empty stream */ 294 string_stream_append(stream_1, stream_2); 295 KUNIT_EXPECT_EQ(test, strlen(get_concatenated_string(test, stream_1)), 0); 296 297 /* Add some data to stream_1 */ 298 for (i = 0; i < ARRAY_SIZE(strings_1); ++i) 299 string_stream_add(stream_1, "%s\n", strings_1[i]); 300 301 stream1_content_before_append = get_concatenated_string(test, stream_1); 302 303 /* Append content of empty stream to non-empty stream */ 304 string_stream_append(stream_1, stream_2); 305 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), 306 stream1_content_before_append); 307 308 /* Add some data to stream_2 */ 309 for (i = 0; i < ARRAY_SIZE(strings_2); ++i) 310 string_stream_add(stream_2, "%s\n", strings_2[i]); 311 312 /* Append content of non-empty stream to non-empty stream */ 313 string_stream_append(stream_1, stream_2); 314 315 /* 316 * End result should be the original content of stream_1 plus 317 * the content of stream_2. 318 */ 319 stream_2_content = get_concatenated_string(test, stream_2); 320 combined_length = strlen(stream1_content_before_append) + strlen(stream_2_content); 321 combined_length++; /* for terminating \0 */ 322 combined_content = kunit_kmalloc(test, combined_length, GFP_KERNEL); 323 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, combined_content); 324 snprintf(combined_content, combined_length, "%s%s", 325 stream1_content_before_append, stream_2_content); 326 327 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), combined_content); 328 329 /* Append content of non-empty stream to empty stream */ 330 kunit_free_string_stream(test, stream_1); 331 332 stream_1 = kunit_alloc_string_stream(test, GFP_KERNEL); 333 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_1); 334 335 string_stream_append(stream_1, stream_2); 336 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), stream_2_content); 337 } 338 339 /* Appending the content of one string stream to one with auto-newlining. */ 340 static void string_stream_append_auto_newline_test(struct kunit *test) 341 { 342 struct string_stream *stream_1, *stream_2; 343 344 /* Stream 1 has newline appending enabled */ 345 stream_1 = kunit_alloc_string_stream(test, GFP_KERNEL); 346 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_1); 347 string_stream_set_append_newlines(stream_1, true); 348 KUNIT_EXPECT_TRUE(test, stream_1->append_newlines); 349 350 /* Stream 2 does not append newlines */ 351 stream_2 = kunit_alloc_string_stream(test, GFP_KERNEL); 352 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_2); 353 354 /* Appending a stream with a newline should not add another newline */ 355 string_stream_add(stream_1, "Original string\n"); 356 string_stream_add(stream_2, "Appended content\n"); 357 string_stream_add(stream_2, "More stuff\n"); 358 string_stream_append(stream_1, stream_2); 359 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), 360 "Original string\nAppended content\nMore stuff\n"); 361 362 kunit_free_string_stream(test, stream_2); 363 stream_2 = kunit_alloc_string_stream(test, GFP_KERNEL); 364 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_2); 365 366 /* 367 * Appending a stream without newline should add a final newline. 368 * The appended string_stream is treated as a single string so newlines 369 * should not be inserted between fragments. 370 */ 371 string_stream_add(stream_2, "Another"); 372 string_stream_add(stream_2, "And again"); 373 string_stream_append(stream_1, stream_2); 374 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), 375 "Original string\nAppended content\nMore stuff\nAnotherAnd again\n"); 376 } 377 378 /* Adding an empty string should not create a fragment. */ 379 static void string_stream_append_empty_string_test(struct kunit *test) 380 { 381 struct string_stream *stream; 382 int original_frag_count; 383 384 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 385 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 386 387 /* Formatted empty string */ 388 string_stream_add(stream, "%s", ""); 389 KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream)); 390 KUNIT_EXPECT_TRUE(test, list_empty(&stream->fragments)); 391 392 /* Adding an empty string to a non-empty stream */ 393 string_stream_add(stream, "Add this line"); 394 original_frag_count = list_count_nodes(&stream->fragments); 395 396 string_stream_add(stream, "%s", ""); 397 KUNIT_EXPECT_EQ(test, list_count_nodes(&stream->fragments), original_frag_count); 398 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream), "Add this line"); 399 } 400 401 /* Adding strings without automatic newline appending */ 402 static void string_stream_no_auto_newline_test(struct kunit *test) 403 { 404 struct string_stream *stream; 405 406 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 407 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 408 409 /* 410 * Add some strings with and without newlines. All formatted newlines 411 * should be preserved. It should not add any extra newlines. 412 */ 413 string_stream_add(stream, "One"); 414 string_stream_add(stream, "Two\n"); 415 string_stream_add(stream, "%s\n", "Three"); 416 string_stream_add(stream, "%s", "Four\n"); 417 string_stream_add(stream, "Five\n%s", "Six"); 418 string_stream_add(stream, "Seven\n\n"); 419 string_stream_add(stream, "Eight"); 420 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream), 421 "OneTwo\nThree\nFour\nFive\nSixSeven\n\nEight"); 422 } 423 424 /* Adding strings with automatic newline appending */ 425 static void string_stream_auto_newline_test(struct kunit *test) 426 { 427 struct string_stream *stream; 428 429 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 430 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 431 432 string_stream_set_append_newlines(stream, true); 433 KUNIT_EXPECT_TRUE(test, stream->append_newlines); 434 435 /* 436 * Add some strings with and without newlines. Newlines should 437 * be appended to lines that do not end with \n, but newlines 438 * resulting from the formatting should not be changed. 439 */ 440 string_stream_add(stream, "One"); 441 string_stream_add(stream, "Two\n"); 442 string_stream_add(stream, "%s\n", "Three"); 443 string_stream_add(stream, "%s", "Four\n"); 444 string_stream_add(stream, "Five\n%s", "Six"); 445 string_stream_add(stream, "Seven\n\n"); 446 string_stream_add(stream, "Eight"); 447 KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream), 448 "One\nTwo\nThree\nFour\nFive\nSix\nSeven\n\nEight\n"); 449 } 450 451 /* 452 * This doesn't actually "test" anything. It reports time taken 453 * and memory used for logging a large number of lines. 454 */ 455 static void string_stream_performance_test(struct kunit *test) 456 { 457 struct string_stream_fragment *frag_container; 458 struct string_stream *stream; 459 char test_line[101]; 460 ktime_t start_time, end_time; 461 size_t len, bytes_requested, actual_bytes_used, total_string_length; 462 int offset, i; 463 464 stream = kunit_alloc_string_stream(test, GFP_KERNEL); 465 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream); 466 467 memset(test_line, 'x', sizeof(test_line) - 1); 468 test_line[sizeof(test_line) - 1] = '\0'; 469 470 start_time = ktime_get(); 471 for (i = 0; i < 10000; i++) { 472 offset = i % (sizeof(test_line) - 1); 473 string_stream_add(stream, "%s: %d\n", &test_line[offset], i); 474 } 475 end_time = ktime_get(); 476 477 /* 478 * Calculate memory used. This doesn't include invisible 479 * overhead due to kernel allocator fragment size rounding. 480 */ 481 bytes_requested = sizeof(*stream); 482 actual_bytes_used = ksize(stream); 483 total_string_length = 0; 484 485 list_for_each_entry(frag_container, &stream->fragments, node) { 486 bytes_requested += sizeof(*frag_container); 487 actual_bytes_used += ksize(frag_container); 488 489 len = strlen(frag_container->fragment); 490 total_string_length += len; 491 bytes_requested += len + 1; /* +1 for '\0' */ 492 actual_bytes_used += ksize(frag_container->fragment); 493 } 494 495 kunit_info(test, "Time elapsed: %lld us\n", 496 ktime_us_delta(end_time, start_time)); 497 kunit_info(test, "Total string length: %zu\n", total_string_length); 498 kunit_info(test, "Bytes requested: %zu\n", bytes_requested); 499 kunit_info(test, "Actual bytes allocated: %zu\n", actual_bytes_used); 500 } 501 502 static int string_stream_test_init(struct kunit *test) 503 { 504 struct string_stream_test_priv *priv; 505 506 priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL); 507 if (!priv) 508 return -ENOMEM; 509 510 test->priv = priv; 511 512 return 0; 513 } 514 515 static struct kunit_case string_stream_test_cases[] = { 516 KUNIT_CASE(string_stream_managed_init_test), 517 KUNIT_CASE(string_stream_unmanaged_init_test), 518 KUNIT_CASE(string_stream_managed_free_test), 519 KUNIT_CASE(string_stream_resource_free_test), 520 KUNIT_CASE(string_stream_line_add_test), 521 KUNIT_CASE(string_stream_variable_length_line_test), 522 KUNIT_CASE(string_stream_append_test), 523 KUNIT_CASE(string_stream_append_auto_newline_test), 524 KUNIT_CASE(string_stream_append_empty_string_test), 525 KUNIT_CASE(string_stream_no_auto_newline_test), 526 KUNIT_CASE(string_stream_auto_newline_test), 527 KUNIT_CASE(string_stream_performance_test), 528 {} 529 }; 530 531 static struct kunit_suite string_stream_test_suite = { 532 .name = "string-stream-test", 533 .test_cases = string_stream_test_cases, 534 .init = string_stream_test_init, 535 }; 536 kunit_test_suites(&string_stream_test_suite); 537