Args.cpp revision 336823
1//===-- Args.cpp ------------------------------------------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10#include "lldb/Utility/Args.h" 11#include "lldb/Utility/ConstString.h" 12#include "lldb/Utility/FileSpec.h" 13#include "lldb/Utility/Stream.h" 14#include "lldb/Utility/StringList.h" 15#include "llvm/ADT/StringSwitch.h" 16 17using namespace lldb; 18using namespace lldb_private; 19 20// A helper function for argument parsing. 21// Parses the initial part of the first argument using normal double quote 22// rules: backslash escapes the double quote and itself. The parsed string is 23// appended to the second argument. The function returns the unparsed portion 24// of the string, starting at the closing quote. 25static llvm::StringRef ParseDoubleQuotes(llvm::StringRef quoted, 26 std::string &result) { 27 // Inside double quotes, '\' and '"' are special. 28 static const char *k_escapable_characters = "\"\\"; 29 while (true) { 30 // Skip over over regular characters and append them. 31 size_t regular = quoted.find_first_of(k_escapable_characters); 32 result += quoted.substr(0, regular); 33 quoted = quoted.substr(regular); 34 35 // If we have reached the end of string or the closing quote, we're done. 36 if (quoted.empty() || quoted.front() == '"') 37 break; 38 39 // We have found a backslash. 40 quoted = quoted.drop_front(); 41 42 if (quoted.empty()) { 43 // A lone backslash at the end of string, let's just append it. 44 result += '\\'; 45 break; 46 } 47 48 // If the character after the backslash is not a whitelisted escapable 49 // character, we leave the character sequence untouched. 50 if (strchr(k_escapable_characters, quoted.front()) == nullptr) 51 result += '\\'; 52 53 result += quoted.front(); 54 quoted = quoted.drop_front(); 55 } 56 57 return quoted; 58} 59 60static size_t ArgvToArgc(const char **argv) { 61 if (!argv) 62 return 0; 63 size_t count = 0; 64 while (*argv++) 65 ++count; 66 return count; 67} 68 69// Trims all whitespace that can separate command line arguments from the left 70// side of the string. 71static llvm::StringRef ltrimForArgs(llvm::StringRef str) { 72 static const char *k_space_separators = " \t"; 73 return str.ltrim(k_space_separators); 74} 75 76// A helper function for SetCommandString. Parses a single argument from the 77// command string, processing quotes and backslashes in a shell-like manner. 78// The function returns a tuple consisting of the parsed argument, the quote 79// char used, and the unparsed portion of the string starting at the first 80// unqouted, unescaped whitespace character. 81static std::tuple<std::string, char, llvm::StringRef> 82ParseSingleArgument(llvm::StringRef command) { 83 // Argument can be split into multiple discontiguous pieces, for example: 84 // "Hello ""World" 85 // this would result in a single argument "Hello World" (without the quotes) 86 // since the quotes would be removed and there is not space between the 87 // strings. 88 std::string arg; 89 90 // Since we can have multiple quotes that form a single command in a command 91 // like: "Hello "world'!' (which will make a single argument "Hello world!") 92 // we remember the first quote character we encounter and use that for the 93 // quote character. 94 char first_quote_char = '\0'; 95 96 bool arg_complete = false; 97 do { 98 // Skip over over regular characters and append them. 99 size_t regular = command.find_first_of(" \t\"'`\\"); 100 arg += command.substr(0, regular); 101 command = command.substr(regular); 102 103 if (command.empty()) 104 break; 105 106 char special = command.front(); 107 command = command.drop_front(); 108 switch (special) { 109 case '\\': 110 if (command.empty()) { 111 arg += '\\'; 112 break; 113 } 114 115 // If the character after the backslash is not a whitelisted escapable 116 // character, we leave the character sequence untouched. 117 if (strchr(" \t\\'\"`", command.front()) == nullptr) 118 arg += '\\'; 119 120 arg += command.front(); 121 command = command.drop_front(); 122 123 break; 124 125 case ' ': 126 case '\t': 127 // We are not inside any quotes, we just found a space after an argument. 128 // We are done. 129 arg_complete = true; 130 break; 131 132 case '"': 133 case '\'': 134 case '`': 135 // We found the start of a quote scope. 136 if (first_quote_char == '\0') 137 first_quote_char = special; 138 139 if (special == '"') 140 command = ParseDoubleQuotes(command, arg); 141 else { 142 // For single quotes, we simply skip ahead to the matching quote 143 // character (or the end of the string). 144 size_t quoted = command.find(special); 145 arg += command.substr(0, quoted); 146 command = command.substr(quoted); 147 } 148 149 // If we found a closing quote, skip it. 150 if (!command.empty()) 151 command = command.drop_front(); 152 153 break; 154 } 155 } while (!arg_complete); 156 157 return std::make_tuple(arg, first_quote_char, command); 158} 159 160Args::ArgEntry::ArgEntry(llvm::StringRef str, char quote) : quote(quote) { 161 size_t size = str.size(); 162 ptr.reset(new char[size + 1]); 163 164 ::memcpy(data(), str.data() ? str.data() : "", size); 165 ptr[size] = 0; 166 ref = llvm::StringRef(c_str(), size); 167} 168 169//---------------------------------------------------------------------- 170// Args constructor 171//---------------------------------------------------------------------- 172Args::Args(llvm::StringRef command) { SetCommandString(command); } 173 174Args::Args(const Args &rhs) { *this = rhs; } 175 176Args::Args(const StringList &list) : Args() { 177 for (size_t i = 0; i < list.GetSize(); ++i) 178 AppendArgument(list[i]); 179} 180 181Args &Args::operator=(const Args &rhs) { 182 Clear(); 183 184 m_argv.clear(); 185 m_entries.clear(); 186 for (auto &entry : rhs.m_entries) { 187 m_entries.emplace_back(entry.ref, entry.quote); 188 m_argv.push_back(m_entries.back().data()); 189 } 190 m_argv.push_back(nullptr); 191 return *this; 192} 193 194//---------------------------------------------------------------------- 195// Destructor 196//---------------------------------------------------------------------- 197Args::~Args() {} 198 199void Args::Dump(Stream &s, const char *label_name) const { 200 if (!label_name) 201 return; 202 203 int i = 0; 204 for (auto &entry : m_entries) { 205 s.Indent(); 206 s.Format("{0}[{1}]=\"{2}\"\n", label_name, i++, entry.ref); 207 } 208 s.Format("{0}[{1}]=NULL\n", label_name, i); 209 s.EOL(); 210} 211 212bool Args::GetCommandString(std::string &command) const { 213 command.clear(); 214 215 for (size_t i = 0; i < m_entries.size(); ++i) { 216 if (i > 0) 217 command += ' '; 218 command += m_entries[i].ref; 219 } 220 221 return !m_entries.empty(); 222} 223 224bool Args::GetQuotedCommandString(std::string &command) const { 225 command.clear(); 226 227 for (size_t i = 0; i < m_entries.size(); ++i) { 228 if (i > 0) 229 command += ' '; 230 231 if (m_entries[i].quote) { 232 command += m_entries[i].quote; 233 command += m_entries[i].ref; 234 command += m_entries[i].quote; 235 } else { 236 command += m_entries[i].ref; 237 } 238 } 239 240 return !m_entries.empty(); 241} 242 243void Args::SetCommandString(llvm::StringRef command) { 244 Clear(); 245 m_argv.clear(); 246 247 command = ltrimForArgs(command); 248 std::string arg; 249 char quote; 250 while (!command.empty()) { 251 std::tie(arg, quote, command) = ParseSingleArgument(command); 252 m_entries.emplace_back(arg, quote); 253 m_argv.push_back(m_entries.back().data()); 254 command = ltrimForArgs(command); 255 } 256 m_argv.push_back(nullptr); 257} 258 259size_t Args::GetArgumentCount() const { return m_entries.size(); } 260 261const char *Args::GetArgumentAtIndex(size_t idx) const { 262 if (idx < m_argv.size()) 263 return m_argv[idx]; 264 return nullptr; 265} 266 267char Args::GetArgumentQuoteCharAtIndex(size_t idx) const { 268 if (idx < m_entries.size()) 269 return m_entries[idx].quote; 270 return '\0'; 271} 272 273char **Args::GetArgumentVector() { 274 assert(!m_argv.empty()); 275 // TODO: functions like execve and posix_spawnp exhibit undefined behavior 276 // when argv or envp is null. So the code below is actually wrong. However, 277 // other code in LLDB depends on it being null. The code has been acting 278 // this way for some time, so it makes sense to leave it this way until 279 // someone has the time to come along and fix it. 280 return (m_argv.size() > 1) ? m_argv.data() : nullptr; 281} 282 283const char **Args::GetConstArgumentVector() const { 284 assert(!m_argv.empty()); 285 return (m_argv.size() > 1) ? const_cast<const char **>(m_argv.data()) 286 : nullptr; 287} 288 289void Args::Shift() { 290 // Don't pop the last NULL terminator from the argv array 291 if (m_entries.empty()) 292 return; 293 m_argv.erase(m_argv.begin()); 294 m_entries.erase(m_entries.begin()); 295} 296 297void Args::Unshift(llvm::StringRef arg_str, char quote_char) { 298 InsertArgumentAtIndex(0, arg_str, quote_char); 299} 300 301void Args::AppendArguments(const Args &rhs) { 302 assert(m_argv.size() == m_entries.size() + 1); 303 assert(m_argv.back() == nullptr); 304 m_argv.pop_back(); 305 for (auto &entry : rhs.m_entries) { 306 m_entries.emplace_back(entry.ref, entry.quote); 307 m_argv.push_back(m_entries.back().data()); 308 } 309 m_argv.push_back(nullptr); 310} 311 312void Args::AppendArguments(const char **argv) { 313 size_t argc = ArgvToArgc(argv); 314 315 assert(m_argv.size() == m_entries.size() + 1); 316 assert(m_argv.back() == nullptr); 317 m_argv.pop_back(); 318 for (auto arg : llvm::makeArrayRef(argv, argc)) { 319 m_entries.emplace_back(arg, '\0'); 320 m_argv.push_back(m_entries.back().data()); 321 } 322 323 m_argv.push_back(nullptr); 324} 325 326void Args::AppendArgument(llvm::StringRef arg_str, char quote_char) { 327 InsertArgumentAtIndex(GetArgumentCount(), arg_str, quote_char); 328} 329 330void Args::InsertArgumentAtIndex(size_t idx, llvm::StringRef arg_str, 331 char quote_char) { 332 assert(m_argv.size() == m_entries.size() + 1); 333 assert(m_argv.back() == nullptr); 334 335 if (idx > m_entries.size()) 336 return; 337 m_entries.emplace(m_entries.begin() + idx, arg_str, quote_char); 338 m_argv.insert(m_argv.begin() + idx, m_entries[idx].data()); 339} 340 341void Args::ReplaceArgumentAtIndex(size_t idx, llvm::StringRef arg_str, 342 char quote_char) { 343 assert(m_argv.size() == m_entries.size() + 1); 344 assert(m_argv.back() == nullptr); 345 346 if (idx >= m_entries.size()) 347 return; 348 349 if (arg_str.size() > m_entries[idx].ref.size()) { 350 m_entries[idx] = ArgEntry(arg_str, quote_char); 351 m_argv[idx] = m_entries[idx].data(); 352 } else { 353 const char *src_data = arg_str.data() ? arg_str.data() : ""; 354 ::memcpy(m_entries[idx].data(), src_data, arg_str.size()); 355 m_entries[idx].ptr[arg_str.size()] = 0; 356 m_entries[idx].ref = m_entries[idx].ref.take_front(arg_str.size()); 357 } 358} 359 360void Args::DeleteArgumentAtIndex(size_t idx) { 361 if (idx >= m_entries.size()) 362 return; 363 364 m_argv.erase(m_argv.begin() + idx); 365 m_entries.erase(m_entries.begin() + idx); 366} 367 368void Args::SetArguments(size_t argc, const char **argv) { 369 Clear(); 370 371 auto args = llvm::makeArrayRef(argv, argc); 372 m_entries.resize(argc); 373 m_argv.resize(argc + 1); 374 for (size_t i = 0; i < args.size(); ++i) { 375 char quote = 376 ((args[i][0] == '\'') || (args[i][0] == '"') || (args[i][0] == '`')) 377 ? args[i][0] 378 : '\0'; 379 380 m_entries[i] = ArgEntry(args[i], quote); 381 m_argv[i] = m_entries[i].data(); 382 } 383} 384 385void Args::SetArguments(const char **argv) { 386 SetArguments(ArgvToArgc(argv), argv); 387} 388 389void Args::Clear() { 390 m_entries.clear(); 391 m_argv.clear(); 392 m_argv.push_back(nullptr); 393} 394 395const char *Args::StripSpaces(std::string &s, bool leading, bool trailing, 396 bool return_null_if_empty) { 397 static const char *k_white_space = " \t\v"; 398 if (!s.empty()) { 399 if (leading) { 400 size_t pos = s.find_first_not_of(k_white_space); 401 if (pos == std::string::npos) 402 s.clear(); 403 else if (pos > 0) 404 s.erase(0, pos); 405 } 406 407 if (trailing) { 408 size_t rpos = s.find_last_not_of(k_white_space); 409 if (rpos != std::string::npos && rpos + 1 < s.size()) 410 s.erase(rpos + 1); 411 } 412 } 413 if (return_null_if_empty && s.empty()) 414 return nullptr; 415 return s.c_str(); 416} 417 418const char *Args::GetShellSafeArgument(const FileSpec &shell, 419 const char *unsafe_arg, 420 std::string &safe_arg) { 421 struct ShellDescriptor { 422 ConstString m_basename; 423 const char *m_escapables; 424 }; 425 426 static ShellDescriptor g_Shells[] = {{ConstString("bash"), " '\"<>()&"}, 427 {ConstString("tcsh"), " '\"<>()&$"}, 428 {ConstString("sh"), " '\"<>()&"}}; 429 430 // safe minimal set 431 const char *escapables = " '\""; 432 433 if (auto basename = shell.GetFilename()) { 434 for (const auto &Shell : g_Shells) { 435 if (Shell.m_basename == basename) { 436 escapables = Shell.m_escapables; 437 break; 438 } 439 } 440 } 441 442 safe_arg.assign(unsafe_arg); 443 size_t prev_pos = 0; 444 while (prev_pos < safe_arg.size()) { 445 // Escape spaces and quotes 446 size_t pos = safe_arg.find_first_of(escapables, prev_pos); 447 if (pos != std::string::npos) { 448 safe_arg.insert(pos, 1, '\\'); 449 prev_pos = pos + 2; 450 } else 451 break; 452 } 453 return safe_arg.c_str(); 454} 455 456lldb::Encoding Args::StringToEncoding(llvm::StringRef s, 457 lldb::Encoding fail_value) { 458 return llvm::StringSwitch<lldb::Encoding>(s) 459 .Case("uint", eEncodingUint) 460 .Case("sint", eEncodingSint) 461 .Case("ieee754", eEncodingIEEE754) 462 .Case("vector", eEncodingVector) 463 .Default(fail_value); 464} 465 466uint32_t Args::StringToGenericRegister(llvm::StringRef s) { 467 if (s.empty()) 468 return LLDB_INVALID_REGNUM; 469 uint32_t result = llvm::StringSwitch<uint32_t>(s) 470 .Case("pc", LLDB_REGNUM_GENERIC_PC) 471 .Case("sp", LLDB_REGNUM_GENERIC_SP) 472 .Case("fp", LLDB_REGNUM_GENERIC_FP) 473 .Cases("ra", "lr", LLDB_REGNUM_GENERIC_RA) 474 .Case("flags", LLDB_REGNUM_GENERIC_FLAGS) 475 .Case("arg1", LLDB_REGNUM_GENERIC_ARG1) 476 .Case("arg2", LLDB_REGNUM_GENERIC_ARG2) 477 .Case("arg3", LLDB_REGNUM_GENERIC_ARG3) 478 .Case("arg4", LLDB_REGNUM_GENERIC_ARG4) 479 .Case("arg5", LLDB_REGNUM_GENERIC_ARG5) 480 .Case("arg6", LLDB_REGNUM_GENERIC_ARG6) 481 .Case("arg7", LLDB_REGNUM_GENERIC_ARG7) 482 .Case("arg8", LLDB_REGNUM_GENERIC_ARG8) 483 .Default(LLDB_INVALID_REGNUM); 484 return result; 485} 486 487void Args::EncodeEscapeSequences(const char *src, std::string &dst) { 488 dst.clear(); 489 if (src) { 490 for (const char *p = src; *p != '\0'; ++p) { 491 size_t non_special_chars = ::strcspn(p, "\\"); 492 if (non_special_chars > 0) { 493 dst.append(p, non_special_chars); 494 p += non_special_chars; 495 if (*p == '\0') 496 break; 497 } 498 499 if (*p == '\\') { 500 ++p; // skip the slash 501 switch (*p) { 502 case 'a': 503 dst.append(1, '\a'); 504 break; 505 case 'b': 506 dst.append(1, '\b'); 507 break; 508 case 'f': 509 dst.append(1, '\f'); 510 break; 511 case 'n': 512 dst.append(1, '\n'); 513 break; 514 case 'r': 515 dst.append(1, '\r'); 516 break; 517 case 't': 518 dst.append(1, '\t'); 519 break; 520 case 'v': 521 dst.append(1, '\v'); 522 break; 523 case '\\': 524 dst.append(1, '\\'); 525 break; 526 case '\'': 527 dst.append(1, '\''); 528 break; 529 case '"': 530 dst.append(1, '"'); 531 break; 532 case '0': 533 // 1 to 3 octal chars 534 { 535 // Make a string that can hold onto the initial zero char, up to 3 536 // octal digits, and a terminating NULL. 537 char oct_str[5] = {'\0', '\0', '\0', '\0', '\0'}; 538 539 int i; 540 for (i = 0; (p[i] >= '0' && p[i] <= '7') && i < 4; ++i) 541 oct_str[i] = p[i]; 542 543 // We don't want to consume the last octal character since the main 544 // for loop will do this for us, so we advance p by one less than i 545 // (even if i is zero) 546 p += i - 1; 547 unsigned long octal_value = ::strtoul(oct_str, nullptr, 8); 548 if (octal_value <= UINT8_MAX) { 549 dst.append(1, (char)octal_value); 550 } 551 } 552 break; 553 554 case 'x': 555 // hex number in the format 556 if (isxdigit(p[1])) { 557 ++p; // Skip the 'x' 558 559 // Make a string that can hold onto two hex chars plus a 560 // NULL terminator 561 char hex_str[3] = {*p, '\0', '\0'}; 562 if (isxdigit(p[1])) { 563 ++p; // Skip the first of the two hex chars 564 hex_str[1] = *p; 565 } 566 567 unsigned long hex_value = strtoul(hex_str, nullptr, 16); 568 if (hex_value <= UINT8_MAX) 569 dst.append(1, (char)hex_value); 570 } else { 571 dst.append(1, 'x'); 572 } 573 break; 574 575 default: 576 // Just desensitize any other character by just printing what came 577 // after the '\' 578 dst.append(1, *p); 579 break; 580 } 581 } 582 } 583 } 584} 585 586void Args::ExpandEscapedCharacters(const char *src, std::string &dst) { 587 dst.clear(); 588 if (src) { 589 for (const char *p = src; *p != '\0'; ++p) { 590 if (isprint(*p)) 591 dst.append(1, *p); 592 else { 593 switch (*p) { 594 case '\a': 595 dst.append("\\a"); 596 break; 597 case '\b': 598 dst.append("\\b"); 599 break; 600 case '\f': 601 dst.append("\\f"); 602 break; 603 case '\n': 604 dst.append("\\n"); 605 break; 606 case '\r': 607 dst.append("\\r"); 608 break; 609 case '\t': 610 dst.append("\\t"); 611 break; 612 case '\v': 613 dst.append("\\v"); 614 break; 615 case '\'': 616 dst.append("\\'"); 617 break; 618 case '"': 619 dst.append("\\\""); 620 break; 621 case '\\': 622 dst.append("\\\\"); 623 break; 624 default: { 625 // Just encode as octal 626 dst.append("\\0"); 627 char octal_str[32]; 628 snprintf(octal_str, sizeof(octal_str), "%o", *p); 629 dst.append(octal_str); 630 } break; 631 } 632 } 633 } 634 } 635} 636 637std::string Args::EscapeLLDBCommandArgument(const std::string &arg, 638 char quote_char) { 639 const char *chars_to_escape = nullptr; 640 switch (quote_char) { 641 case '\0': 642 chars_to_escape = " \t\\'\"`"; 643 break; 644 case '\'': 645 chars_to_escape = ""; 646 break; 647 case '"': 648 chars_to_escape = "$\"`\\"; 649 break; 650 default: 651 assert(false && "Unhandled quote character"); 652 } 653 654 std::string res; 655 res.reserve(arg.size()); 656 for (char c : arg) { 657 if (::strchr(chars_to_escape, c)) 658 res.push_back('\\'); 659 res.push_back(c); 660 } 661 return res; 662} 663 664OptionsWithRaw::OptionsWithRaw(llvm::StringRef arg_string) { 665 SetFromString(arg_string); 666} 667 668void OptionsWithRaw::SetFromString(llvm::StringRef arg_string) { 669 const llvm::StringRef original_args = arg_string; 670 671 arg_string = ltrimForArgs(arg_string); 672 std::string arg; 673 char quote; 674 675 // If the string doesn't start with a dash, we just have no options and just 676 // a raw part. 677 if (!arg_string.startswith("-")) { 678 m_suffix = original_args; 679 return; 680 } 681 682 bool found_suffix = false; 683 684 while (!arg_string.empty()) { 685 // The length of the prefix before parsing. 686 std::size_t prev_prefix_length = original_args.size() - arg_string.size(); 687 688 // Parse the next argument from the remaining string. 689 std::tie(arg, quote, arg_string) = ParseSingleArgument(arg_string); 690 691 // If we get an unquoted '--' argument, then we reached the suffix part 692 // of the command. 693 Args::ArgEntry entry(arg, quote); 694 if (!entry.IsQuoted() && arg == "--") { 695 // The remaining line is the raw suffix, and the line we parsed so far 696 // needs to be interpreted as arguments. 697 m_has_args = true; 698 m_suffix = arg_string; 699 found_suffix = true; 700 701 // The length of the prefix after parsing. 702 std::size_t prefix_length = original_args.size() - arg_string.size(); 703 704 // Take the string we know contains all the arguments and actually parse 705 // it as proper arguments. 706 llvm::StringRef prefix = original_args.take_front(prev_prefix_length); 707 m_args = Args(prefix); 708 m_arg_string = prefix; 709 710 // We also record the part of the string that contains the arguments plus 711 // the delimiter. 712 m_arg_string_with_delimiter = original_args.take_front(prefix_length); 713 714 // As the rest of the string became the raw suffix, we are done here. 715 break; 716 } 717 718 arg_string = ltrimForArgs(arg_string); 719 } 720 721 // If we didn't find a suffix delimiter, the whole string is the raw suffix. 722 if (!found_suffix) { 723 found_suffix = true; 724 m_suffix = original_args; 725 } 726} 727