1 //===-- Args.cpp ----------------------------------------------------------===// 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 "lldb/Utility/Args.h" 10 #include "lldb/Utility/FileSpec.h" 11 #include "lldb/Utility/Stream.h" 12 #include "lldb/Utility/StringList.h" 13 #include "llvm/ADT/StringSwitch.h" 14 15 using namespace lldb; 16 using namespace lldb_private; 17 18 // A helper function for argument parsing. 19 // Parses the initial part of the first argument using normal double quote 20 // rules: backslash escapes the double quote and itself. The parsed string is 21 // appended to the second argument. The function returns the unparsed portion 22 // of the string, starting at the closing quote. 23 static llvm::StringRef ParseDoubleQuotes(llvm::StringRef quoted, 24 std::string &result) { 25 // Inside double quotes, '\' and '"' are special. 26 static const char *k_escapable_characters = "\"\\"; 27 while (true) { 28 // Skip over regular characters and append them. 29 size_t regular = quoted.find_first_of(k_escapable_characters); 30 result += quoted.substr(0, regular); 31 quoted = quoted.substr(regular); 32 33 // If we have reached the end of string or the closing quote, we're done. 34 if (quoted.empty() || quoted.front() == '"') 35 break; 36 37 // We have found a backslash. 38 quoted = quoted.drop_front(); 39 40 if (quoted.empty()) { 41 // A lone backslash at the end of string, let's just append it. 42 result += '\\'; 43 break; 44 } 45 46 // If the character after the backslash is not an allowed escapable 47 // character, we leave the character sequence untouched. 48 if (strchr(k_escapable_characters, quoted.front()) == nullptr) 49 result += '\\'; 50 51 result += quoted.front(); 52 quoted = quoted.drop_front(); 53 } 54 55 return quoted; 56 } 57 58 static size_t ArgvToArgc(const char **argv) { 59 if (!argv) 60 return 0; 61 size_t count = 0; 62 while (*argv++) 63 ++count; 64 return count; 65 } 66 67 // Trims all whitespace that can separate command line arguments from the left 68 // side of the string. 69 static llvm::StringRef ltrimForArgs(llvm::StringRef str) { 70 static const char *k_space_separators = " \t"; 71 return str.ltrim(k_space_separators); 72 } 73 74 // A helper function for SetCommandString. Parses a single argument from the 75 // command string, processing quotes and backslashes in a shell-like manner. 76 // The function returns a tuple consisting of the parsed argument, the quote 77 // char used, and the unparsed portion of the string starting at the first 78 // unqouted, unescaped whitespace character. 79 static std::tuple<std::string, char, llvm::StringRef> 80 ParseSingleArgument(llvm::StringRef command) { 81 // Argument can be split into multiple discontiguous pieces, for example: 82 // "Hello ""World" 83 // this would result in a single argument "Hello World" (without the quotes) 84 // since the quotes would be removed and there is not space between the 85 // strings. 86 std::string arg; 87 88 // Since we can have multiple quotes that form a single command in a command 89 // like: "Hello "world'!' (which will make a single argument "Hello world!") 90 // we remember the first quote character we encounter and use that for the 91 // quote character. 92 char first_quote_char = '\0'; 93 94 bool arg_complete = false; 95 do { 96 // Skip over regular characters and append them. 97 size_t regular = command.find_first_of(" \t\r\"'`\\"); 98 arg += command.substr(0, regular); 99 command = command.substr(regular); 100 101 if (command.empty()) 102 break; 103 104 char special = command.front(); 105 command = command.drop_front(); 106 switch (special) { 107 case '\\': 108 if (command.empty()) { 109 arg += '\\'; 110 break; 111 } 112 113 // If the character after the backslash is not an allowed escapable 114 // character, we leave the character sequence untouched. 115 if (strchr(" \t\\'\"`", command.front()) == nullptr) 116 arg += '\\'; 117 118 arg += command.front(); 119 command = command.drop_front(); 120 121 break; 122 123 case ' ': 124 case '\t': 125 case '\r': 126 // We are not inside any quotes, we just found a space after an argument. 127 // We are done. 128 arg_complete = true; 129 break; 130 131 case '"': 132 case '\'': 133 case '`': 134 // We found the start of a quote scope. 135 if (first_quote_char == '\0') 136 first_quote_char = special; 137 138 if (special == '"') 139 command = ParseDoubleQuotes(command, arg); 140 else { 141 // For single quotes, we simply skip ahead to the matching quote 142 // character (or the end of the string). 143 size_t quoted = command.find(special); 144 arg += command.substr(0, quoted); 145 command = command.substr(quoted); 146 } 147 148 // If we found a closing quote, skip it. 149 if (!command.empty()) 150 command = command.drop_front(); 151 152 break; 153 } 154 } while (!arg_complete); 155 156 return std::make_tuple(arg, first_quote_char, command); 157 } 158 159 Args::ArgEntry::ArgEntry(llvm::StringRef str, char quote) : quote(quote) { 160 size_t size = str.size(); 161 ptr.reset(new char[size + 1]); 162 163 ::memcpy(data(), str.data() ? str.data() : "", size); 164 ptr[size] = 0; 165 } 166 167 // Args constructor 168 Args::Args(llvm::StringRef command) { SetCommandString(command); } 169 170 Args::Args(const Args &rhs) { *this = rhs; } 171 172 Args::Args(const StringList &list) : Args() { 173 for (const std::string &arg : list) 174 AppendArgument(arg); 175 } 176 177 Args::Args(llvm::ArrayRef<llvm::StringRef> args) : Args() { 178 for (llvm::StringRef arg : args) 179 AppendArgument(arg); 180 } 181 182 Args &Args::operator=(const Args &rhs) { 183 Clear(); 184 185 m_argv.clear(); 186 m_entries.clear(); 187 for (auto &entry : rhs.m_entries) { 188 m_entries.emplace_back(entry.ref(), entry.quote); 189 m_argv.push_back(m_entries.back().data()); 190 } 191 m_argv.push_back(nullptr); 192 return *this; 193 } 194 195 // Destructor 196 Args::~Args() = default; 197 198 void Args::Dump(Stream &s, const char *label_name) const { 199 if (!label_name) 200 return; 201 202 int i = 0; 203 for (auto &entry : m_entries) { 204 s.Indent(); 205 s.Format("{0}[{1}]=\"{2}\"\n", label_name, i++, entry.ref()); 206 } 207 s.Format("{0}[{1}]=NULL\n", label_name, i); 208 s.EOL(); 209 } 210 211 bool Args::GetCommandString(std::string &command) const { 212 command.clear(); 213 214 for (size_t i = 0; i < m_entries.size(); ++i) { 215 if (i > 0) 216 command += ' '; 217 char quote = m_entries[i].quote; 218 if (quote != '\0') 219 command += quote; 220 command += m_entries[i].ref(); 221 if (quote != '\0') 222 command += quote; 223 } 224 225 return !m_entries.empty(); 226 } 227 228 bool Args::GetQuotedCommandString(std::string &command) const { 229 command.clear(); 230 231 for (size_t i = 0; i < m_entries.size(); ++i) { 232 if (i > 0) 233 command += ' '; 234 235 if (m_entries[i].quote) { 236 command += m_entries[i].quote; 237 command += m_entries[i].ref(); 238 command += m_entries[i].quote; 239 } else { 240 command += m_entries[i].ref(); 241 } 242 } 243 244 return !m_entries.empty(); 245 } 246 247 void Args::SetCommandString(llvm::StringRef command) { 248 Clear(); 249 m_argv.clear(); 250 251 command = ltrimForArgs(command); 252 std::string arg; 253 char quote; 254 while (!command.empty()) { 255 std::tie(arg, quote, command) = ParseSingleArgument(command); 256 m_entries.emplace_back(arg, quote); 257 m_argv.push_back(m_entries.back().data()); 258 command = ltrimForArgs(command); 259 } 260 m_argv.push_back(nullptr); 261 } 262 263 const char *Args::GetArgumentAtIndex(size_t idx) const { 264 if (idx < m_argv.size()) 265 return m_argv[idx]; 266 return nullptr; 267 } 268 269 char **Args::GetArgumentVector() { 270 assert(!m_argv.empty()); 271 // TODO: functions like execve and posix_spawnp exhibit undefined behavior 272 // when argv or envp is null. So the code below is actually wrong. However, 273 // other code in LLDB depends on it being null. The code has been acting 274 // this way for some time, so it makes sense to leave it this way until 275 // someone has the time to come along and fix it. 276 return (m_argv.size() > 1) ? m_argv.data() : nullptr; 277 } 278 279 const char **Args::GetConstArgumentVector() const { 280 assert(!m_argv.empty()); 281 return (m_argv.size() > 1) ? const_cast<const char **>(m_argv.data()) 282 : nullptr; 283 } 284 285 void Args::Shift() { 286 // Don't pop the last NULL terminator from the argv array 287 if (m_entries.empty()) 288 return; 289 m_argv.erase(m_argv.begin()); 290 m_entries.erase(m_entries.begin()); 291 } 292 293 void Args::Unshift(llvm::StringRef arg_str, char quote_char) { 294 InsertArgumentAtIndex(0, arg_str, quote_char); 295 } 296 297 void Args::AppendArguments(const Args &rhs) { 298 assert(m_argv.size() == m_entries.size() + 1); 299 assert(m_argv.back() == nullptr); 300 m_argv.pop_back(); 301 for (auto &entry : rhs.m_entries) { 302 m_entries.emplace_back(entry.ref(), entry.quote); 303 m_argv.push_back(m_entries.back().data()); 304 } 305 m_argv.push_back(nullptr); 306 } 307 308 void Args::AppendArguments(const char **argv) { 309 size_t argc = ArgvToArgc(argv); 310 311 assert(m_argv.size() == m_entries.size() + 1); 312 assert(m_argv.back() == nullptr); 313 m_argv.pop_back(); 314 for (auto arg : llvm::ArrayRef(argv, argc)) { 315 m_entries.emplace_back(arg, '\0'); 316 m_argv.push_back(m_entries.back().data()); 317 } 318 319 m_argv.push_back(nullptr); 320 } 321 322 void Args::AppendArgument(llvm::StringRef arg_str, char quote_char) { 323 InsertArgumentAtIndex(GetArgumentCount(), arg_str, quote_char); 324 } 325 326 void Args::InsertArgumentAtIndex(size_t idx, llvm::StringRef arg_str, 327 char quote_char) { 328 assert(m_argv.size() == m_entries.size() + 1); 329 assert(m_argv.back() == nullptr); 330 331 if (idx > m_entries.size()) 332 return; 333 m_entries.emplace(m_entries.begin() + idx, arg_str, quote_char); 334 m_argv.insert(m_argv.begin() + idx, m_entries[idx].data()); 335 } 336 337 void Args::ReplaceArgumentAtIndex(size_t idx, llvm::StringRef arg_str, 338 char quote_char) { 339 assert(m_argv.size() == m_entries.size() + 1); 340 assert(m_argv.back() == nullptr); 341 342 if (idx >= m_entries.size()) 343 return; 344 345 m_entries[idx] = ArgEntry(arg_str, quote_char); 346 m_argv[idx] = m_entries[idx].data(); 347 } 348 349 void Args::DeleteArgumentAtIndex(size_t idx) { 350 if (idx >= m_entries.size()) 351 return; 352 353 m_argv.erase(m_argv.begin() + idx); 354 m_entries.erase(m_entries.begin() + idx); 355 } 356 357 void Args::SetArguments(size_t argc, const char **argv) { 358 Clear(); 359 360 auto args = llvm::ArrayRef(argv, argc); 361 m_entries.resize(argc); 362 m_argv.resize(argc + 1); 363 for (size_t i = 0; i < args.size(); ++i) { 364 char quote = 365 ((args[i][0] == '\'') || (args[i][0] == '"') || (args[i][0] == '`')) 366 ? args[i][0] 367 : '\0'; 368 369 m_entries[i] = ArgEntry(args[i], quote); 370 m_argv[i] = m_entries[i].data(); 371 } 372 } 373 374 void Args::SetArguments(const char **argv) { 375 SetArguments(ArgvToArgc(argv), argv); 376 } 377 378 void Args::Clear() { 379 m_entries.clear(); 380 m_argv.clear(); 381 m_argv.push_back(nullptr); 382 } 383 384 std::string Args::GetShellSafeArgument(const FileSpec &shell, 385 llvm::StringRef unsafe_arg) { 386 struct ShellDescriptor { 387 llvm::StringRef m_basename; 388 llvm::StringRef m_escapables; 389 }; 390 391 static ShellDescriptor g_Shells[] = {{"bash", " '\"<>()&;"}, 392 {"fish", " '\"<>()&\\|;"}, 393 {"tcsh", " '\"<>()&;"}, 394 {"zsh", " '\"<>()&;\\|"}, 395 {"sh", " '\"<>()&;"}}; 396 397 // safe minimal set 398 llvm::StringRef escapables = " '\""; 399 400 auto basename = shell.GetFilename().GetStringRef(); 401 if (!basename.empty()) { 402 for (const auto &Shell : g_Shells) { 403 if (Shell.m_basename == basename) { 404 escapables = Shell.m_escapables; 405 break; 406 } 407 } 408 } 409 410 std::string safe_arg; 411 safe_arg.reserve(unsafe_arg.size()); 412 // Add a \ before every character that needs to be escaped. 413 for (char c : unsafe_arg) { 414 if (escapables.contains(c)) 415 safe_arg.push_back('\\'); 416 safe_arg.push_back(c); 417 } 418 return safe_arg; 419 } 420 421 lldb::Encoding Args::StringToEncoding(llvm::StringRef s, 422 lldb::Encoding fail_value) { 423 return llvm::StringSwitch<lldb::Encoding>(s) 424 .Case("uint", eEncodingUint) 425 .Case("sint", eEncodingSint) 426 .Case("ieee754", eEncodingIEEE754) 427 .Case("vector", eEncodingVector) 428 .Default(fail_value); 429 } 430 431 uint32_t Args::StringToGenericRegister(llvm::StringRef s) { 432 if (s.empty()) 433 return LLDB_INVALID_REGNUM; 434 uint32_t result = llvm::StringSwitch<uint32_t>(s) 435 .Case("pc", LLDB_REGNUM_GENERIC_PC) 436 .Case("sp", LLDB_REGNUM_GENERIC_SP) 437 .Case("fp", LLDB_REGNUM_GENERIC_FP) 438 .Cases("ra", "lr", LLDB_REGNUM_GENERIC_RA) 439 .Case("flags", LLDB_REGNUM_GENERIC_FLAGS) 440 .Case("arg1", LLDB_REGNUM_GENERIC_ARG1) 441 .Case("arg2", LLDB_REGNUM_GENERIC_ARG2) 442 .Case("arg3", LLDB_REGNUM_GENERIC_ARG3) 443 .Case("arg4", LLDB_REGNUM_GENERIC_ARG4) 444 .Case("arg5", LLDB_REGNUM_GENERIC_ARG5) 445 .Case("arg6", LLDB_REGNUM_GENERIC_ARG6) 446 .Case("arg7", LLDB_REGNUM_GENERIC_ARG7) 447 .Case("arg8", LLDB_REGNUM_GENERIC_ARG8) 448 .Case("tp", LLDB_REGNUM_GENERIC_TP) 449 .Default(LLDB_INVALID_REGNUM); 450 return result; 451 } 452 453 void Args::EncodeEscapeSequences(const char *src, std::string &dst) { 454 dst.clear(); 455 if (src) { 456 for (const char *p = src; *p != '\0'; ++p) { 457 size_t non_special_chars = ::strcspn(p, "\\"); 458 if (non_special_chars > 0) { 459 dst.append(p, non_special_chars); 460 p += non_special_chars; 461 if (*p == '\0') 462 break; 463 } 464 465 if (*p == '\\') { 466 ++p; // skip the slash 467 switch (*p) { 468 case 'a': 469 dst.append(1, '\a'); 470 break; 471 case 'b': 472 dst.append(1, '\b'); 473 break; 474 case 'f': 475 dst.append(1, '\f'); 476 break; 477 case 'n': 478 dst.append(1, '\n'); 479 break; 480 case 'r': 481 dst.append(1, '\r'); 482 break; 483 case 't': 484 dst.append(1, '\t'); 485 break; 486 case 'v': 487 dst.append(1, '\v'); 488 break; 489 case '\\': 490 dst.append(1, '\\'); 491 break; 492 case '\'': 493 dst.append(1, '\''); 494 break; 495 case '"': 496 dst.append(1, '"'); 497 break; 498 case '0': 499 // 1 to 3 octal chars 500 { 501 // Make a string that can hold onto the initial zero char, up to 3 502 // octal digits, and a terminating NULL. 503 char oct_str[5] = {'\0', '\0', '\0', '\0', '\0'}; 504 505 int i; 506 for (i = 0; (p[i] >= '0' && p[i] <= '7') && i < 4; ++i) 507 oct_str[i] = p[i]; 508 509 // We don't want to consume the last octal character since the main 510 // for loop will do this for us, so we advance p by one less than i 511 // (even if i is zero) 512 p += i - 1; 513 unsigned long octal_value = ::strtoul(oct_str, nullptr, 8); 514 if (octal_value <= UINT8_MAX) { 515 dst.append(1, static_cast<char>(octal_value)); 516 } 517 } 518 break; 519 520 case 'x': 521 // hex number in the format 522 if (isxdigit(p[1])) { 523 ++p; // Skip the 'x' 524 525 // Make a string that can hold onto two hex chars plus a 526 // NULL terminator 527 char hex_str[3] = {*p, '\0', '\0'}; 528 if (isxdigit(p[1])) { 529 ++p; // Skip the first of the two hex chars 530 hex_str[1] = *p; 531 } 532 533 unsigned long hex_value = strtoul(hex_str, nullptr, 16); 534 if (hex_value <= UINT8_MAX) 535 dst.append(1, static_cast<char>(hex_value)); 536 } else { 537 dst.append(1, 'x'); 538 } 539 break; 540 541 default: 542 // Just desensitize any other character by just printing what came 543 // after the '\' 544 dst.append(1, *p); 545 break; 546 } 547 } 548 } 549 } 550 } 551 552 void Args::ExpandEscapedCharacters(const char *src, std::string &dst) { 553 dst.clear(); 554 if (src) { 555 for (const char *p = src; *p != '\0'; ++p) { 556 if (llvm::isPrint(*p)) 557 dst.append(1, *p); 558 else { 559 switch (*p) { 560 case '\a': 561 dst.append("\\a"); 562 break; 563 case '\b': 564 dst.append("\\b"); 565 break; 566 case '\f': 567 dst.append("\\f"); 568 break; 569 case '\n': 570 dst.append("\\n"); 571 break; 572 case '\r': 573 dst.append("\\r"); 574 break; 575 case '\t': 576 dst.append("\\t"); 577 break; 578 case '\v': 579 dst.append("\\v"); 580 break; 581 case '\'': 582 dst.append("\\'"); 583 break; 584 case '"': 585 dst.append("\\\""); 586 break; 587 case '\\': 588 dst.append("\\\\"); 589 break; 590 default: { 591 // Just encode as octal 592 dst.append("\\0"); 593 char octal_str[32]; 594 snprintf(octal_str, sizeof(octal_str), "%o", *p); 595 dst.append(octal_str); 596 } break; 597 } 598 } 599 } 600 } 601 } 602 603 std::string Args::EscapeLLDBCommandArgument(const std::string &arg, 604 char quote_char) { 605 const char *chars_to_escape = nullptr; 606 switch (quote_char) { 607 case '\0': 608 chars_to_escape = " \t\\'\"`"; 609 break; 610 case '"': 611 chars_to_escape = "$\"`\\"; 612 break; 613 case '`': 614 case '\'': 615 return arg; 616 default: 617 assert(false && "Unhandled quote character"); 618 return arg; 619 } 620 621 std::string res; 622 res.reserve(arg.size()); 623 for (char c : arg) { 624 if (::strchr(chars_to_escape, c)) 625 res.push_back('\\'); 626 res.push_back(c); 627 } 628 return res; 629 } 630 631 OptionsWithRaw::OptionsWithRaw(llvm::StringRef arg_string) { 632 SetFromString(arg_string); 633 } 634 635 void OptionsWithRaw::SetFromString(llvm::StringRef arg_string) { 636 const llvm::StringRef original_args = arg_string; 637 638 arg_string = ltrimForArgs(arg_string); 639 std::string arg; 640 char quote; 641 642 // If the string doesn't start with a dash, we just have no options and just 643 // a raw part. 644 if (!arg_string.starts_with("-")) { 645 m_suffix = std::string(original_args); 646 return; 647 } 648 649 bool found_suffix = false; 650 while (!arg_string.empty()) { 651 // The length of the prefix before parsing. 652 std::size_t prev_prefix_length = original_args.size() - arg_string.size(); 653 654 // Parse the next argument from the remaining string. 655 std::tie(arg, quote, arg_string) = ParseSingleArgument(arg_string); 656 657 // If we get an unquoted '--' argument, then we reached the suffix part 658 // of the command. 659 Args::ArgEntry entry(arg, quote); 660 if (!entry.IsQuoted() && arg == "--") { 661 // The remaining line is the raw suffix, and the line we parsed so far 662 // needs to be interpreted as arguments. 663 m_has_args = true; 664 m_suffix = std::string(arg_string); 665 found_suffix = true; 666 667 // The length of the prefix after parsing. 668 std::size_t prefix_length = original_args.size() - arg_string.size(); 669 670 // Take the string we know contains all the arguments and actually parse 671 // it as proper arguments. 672 llvm::StringRef prefix = original_args.take_front(prev_prefix_length); 673 m_args = Args(prefix); 674 m_arg_string = prefix; 675 676 // We also record the part of the string that contains the arguments plus 677 // the delimiter. 678 m_arg_string_with_delimiter = original_args.take_front(prefix_length); 679 680 // As the rest of the string became the raw suffix, we are done here. 681 break; 682 } 683 684 arg_string = ltrimForArgs(arg_string); 685 } 686 687 // If we didn't find a suffix delimiter, the whole string is the raw suffix. 688 if (!found_suffix) 689 m_suffix = std::string(original_args); 690 } 691