702 lines · cpp
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-exception6//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 15using namespace lldb;16using namespace lldb_private;17 18// A helper function for argument parsing.19// Parses the initial part of the first argument using normal double quote20// rules: backslash escapes the double quote and itself. The parsed string is21// appended to the second argument. The function returns the unparsed portion22// of the string, starting at the closing quote.23static 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 escapable47 // 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 58static 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 left68// side of the string.69static llvm::StringRef ltrimForArgs(llvm::StringRef str, size_t &shift) {70 static const char *k_space_separators = " \t";71 llvm::StringRef result = str.ltrim(k_space_separators);72 shift = result.data() - str.data();73 return result;74}75 76// A helper function for SetCommandString. Parses a single argument from the77// command string, processing quotes and backslashes in a shell-like manner.78// The function returns a tuple consisting of the parsed argument, the quote79// char used, and the unparsed portion of the string starting at the first80// 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 the87 // strings.88 std::string arg;89 90 // Since we can have multiple quotes that form a single command in a command91 // like: "Hello "world'!' (which will make a single argument "Hello world!")92 // we remember the first quote character we encounter and use that for the93 // quote character.94 char first_quote_char = '\0';95 96 bool arg_complete = false;97 do {98 // Skip over regular characters and append them.99 size_t regular = command.find_first_of(" \t\r\"'`\\");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 an allowed escapable116 // 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 case '\r':128 // We are not inside any quotes, we just found a space after an argument.129 // We are done.130 arg_complete = true;131 break;132 133 case '"':134 case '\'':135 case '`':136 // We found the start of a quote scope.137 if (first_quote_char == '\0')138 first_quote_char = special;139 140 if (special == '"')141 command = ParseDoubleQuotes(command, arg);142 else {143 // For single quotes, we simply skip ahead to the matching quote144 // character (or the end of the string).145 size_t quoted = command.find(special);146 arg += command.substr(0, quoted);147 command = command.substr(quoted);148 }149 150 // If we found a closing quote, skip it.151 if (!command.empty())152 command = command.drop_front();153 154 break;155 }156 } while (!arg_complete);157 158 return std::make_tuple(arg, first_quote_char, command);159}160 161Args::ArgEntry::ArgEntry(llvm::StringRef str, char quote,162 std::optional<uint16_t> column)163 : quote(quote), column(column) {164 size_t size = str.size();165 ptr.reset(new char[size + 1]);166 167 ::memcpy(data(), str.data() ? str.data() : "", size);168 ptr[size] = 0;169}170 171// Args constructor172Args::Args(llvm::StringRef command) { SetCommandString(command); }173 174Args::Args(const Args &rhs) { *this = rhs; }175 176Args::Args(const StringList &list) : Args() {177 for (const std::string &arg : list)178 AppendArgument(arg);179}180 181Args::Args(llvm::ArrayRef<llvm::StringRef> args) : Args() {182 for (llvm::StringRef arg : args)183 AppendArgument(arg);184}185 186Args &Args::operator=(const Args &rhs) {187 Clear();188 189 m_argv.clear();190 m_entries.clear();191 for (auto &entry : rhs.m_entries) {192 m_entries.emplace_back(entry.ref(), entry.quote, entry.column);193 m_argv.push_back(m_entries.back().data());194 }195 m_argv.push_back(nullptr);196 return *this;197}198 199// Destructor200Args::~Args() = default;201 202void Args::Dump(Stream &s, const char *label_name) const {203 if (!label_name)204 return;205 206 int i = 0;207 for (auto &entry : m_entries) {208 s.Indent();209 s.Format("{0}[{1}]=\"{2}\"\n", label_name, i++, entry.ref());210 }211 s.Format("{0}[{1}]=NULL\n", label_name, i);212 s.EOL();213}214 215bool Args::GetCommandString(std::string &command) const {216 command.clear();217 218 for (size_t i = 0; i < m_entries.size(); ++i) {219 if (i > 0)220 command += ' ';221 char quote = m_entries[i].quote;222 if (quote != '\0')223 command += quote;224 command += m_entries[i].ref();225 if (quote != '\0')226 command += quote;227 }228 229 return !m_entries.empty();230}231 232bool Args::GetQuotedCommandString(std::string &command) const {233 command.clear();234 235 for (size_t i = 0; i < m_entries.size(); ++i) {236 if (i > 0)237 command += ' ';238 239 if (m_entries[i].quote) {240 command += m_entries[i].quote;241 command += m_entries[i].ref();242 command += m_entries[i].quote;243 } else {244 command += m_entries[i].ref();245 }246 }247 248 return !m_entries.empty();249}250 251void Args::SetCommandString(llvm::StringRef command) {252 Clear();253 m_argv.clear();254 255 uint16_t column = 1;256 size_t shift = 0;257 command = ltrimForArgs(command, shift);258 column += shift;259 std::string arg;260 char quote;261 while (!command.empty()) {262 const char *prev = command.data();263 std::tie(arg, quote, command) = ParseSingleArgument(command);264 m_entries.emplace_back(arg, quote, column);265 m_argv.push_back(m_entries.back().data());266 command = ltrimForArgs(command, shift);267 column += shift;268 column += command.data() - prev;269 }270 m_argv.push_back(nullptr);271}272 273const char *Args::GetArgumentAtIndex(size_t idx) const {274 if (idx < m_argv.size())275 return m_argv[idx];276 return nullptr;277}278 279char **Args::GetArgumentVector() {280 assert(!m_argv.empty());281 // TODO: functions like execve and posix_spawnp exhibit undefined behavior282 // when argv or envp is null. So the code below is actually wrong. However,283 // other code in LLDB depends on it being null. The code has been acting284 // this way for some time, so it makes sense to leave it this way until285 // someone has the time to come along and fix it.286 return (m_argv.size() > 1) ? m_argv.data() : nullptr;287}288 289const char **Args::GetConstArgumentVector() const {290 assert(!m_argv.empty());291 return (m_argv.size() > 1) ? const_cast<const char **>(m_argv.data())292 : nullptr;293}294 295void Args::Shift() {296 // Don't pop the last NULL terminator from the argv array297 if (m_entries.empty())298 return;299 m_argv.erase(m_argv.begin());300 m_entries.erase(m_entries.begin());301}302 303void Args::Unshift(llvm::StringRef arg_str, char quote_char) {304 InsertArgumentAtIndex(0, arg_str, quote_char);305}306 307void Args::AppendArguments(const Args &rhs) {308 assert(m_argv.size() == m_entries.size() + 1);309 assert(m_argv.back() == nullptr);310 m_argv.pop_back();311 for (auto &entry : rhs.m_entries) {312 m_entries.emplace_back(entry.ref(), entry.quote, entry.column);313 m_argv.push_back(m_entries.back().data());314 }315 m_argv.push_back(nullptr);316}317 318void Args::AppendArguments(const char **argv) {319 size_t argc = ArgvToArgc(argv);320 321 assert(m_argv.size() == m_entries.size() + 1);322 assert(m_argv.back() == nullptr);323 m_argv.pop_back();324 for (auto arg : llvm::ArrayRef(argv, argc)) {325 m_entries.emplace_back(arg, '\0', std::nullopt);326 m_argv.push_back(m_entries.back().data());327 }328 329 m_argv.push_back(nullptr);330}331 332void Args::AppendArgument(llvm::StringRef arg_str, char quote_char) {333 InsertArgumentAtIndex(GetArgumentCount(), arg_str, quote_char);334}335 336void Args::InsertArgumentAtIndex(size_t idx, llvm::StringRef arg_str,337 char quote_char) {338 assert(m_argv.size() == m_entries.size() + 1);339 assert(m_argv.back() == nullptr);340 341 if (idx > m_entries.size())342 return;343 m_entries.emplace(m_entries.begin() + idx, arg_str, quote_char, std::nullopt);344 m_argv.insert(m_argv.begin() + idx, m_entries[idx].data());345}346 347void Args::ReplaceArgumentAtIndex(size_t idx, llvm::StringRef arg_str,348 char quote_char) {349 assert(m_argv.size() == m_entries.size() + 1);350 assert(m_argv.back() == nullptr);351 352 if (idx >= m_entries.size())353 return;354 355 m_entries[idx] = ArgEntry(arg_str, quote_char, std::nullopt);356 m_argv[idx] = m_entries[idx].data();357}358 359void Args::DeleteArgumentAtIndex(size_t idx) {360 if (idx >= m_entries.size())361 return;362 363 m_argv.erase(m_argv.begin() + idx);364 m_entries.erase(m_entries.begin() + idx);365}366 367void Args::SetArguments(size_t argc, const char **argv) {368 Clear();369 370 auto args = llvm::ArrayRef(argv, argc);371 m_entries.resize(argc);372 m_argv.resize(argc + 1);373 for (size_t i = 0; i < args.size(); ++i) {374 char quote =375 ((args[i][0] == '\'') || (args[i][0] == '"') || (args[i][0] == '`'))376 ? args[i][0]377 : '\0';378 379 m_entries[i] = ArgEntry(args[i], quote, std::nullopt);380 m_argv[i] = m_entries[i].data();381 }382}383 384void Args::SetArguments(const char **argv) {385 SetArguments(ArgvToArgc(argv), argv);386}387 388void Args::Clear() {389 m_entries.clear();390 m_argv.clear();391 m_argv.push_back(nullptr);392}393 394std::string Args::GetShellSafeArgument(const FileSpec &shell,395 llvm::StringRef unsafe_arg) {396 struct ShellDescriptor {397 llvm::StringRef m_basename;398 llvm::StringRef m_escapables;399 };400 401 static ShellDescriptor g_Shells[] = {{"bash", " '\"<>()&;"},402 {"fish", " '\"<>()&\\|;"},403 {"tcsh", " '\"<>()&;"},404 {"zsh", " '\"<>()&;\\|"},405 {"sh", " '\"<>()&;"}};406 407 // safe minimal set408 llvm::StringRef escapables = " '\"";409 410 auto basename = shell.GetFilename().GetStringRef();411 if (!basename.empty()) {412 for (const auto &Shell : g_Shells) {413 if (Shell.m_basename == basename) {414 escapables = Shell.m_escapables;415 break;416 }417 }418 }419 420 std::string safe_arg;421 safe_arg.reserve(unsafe_arg.size());422 // Add a \ before every character that needs to be escaped.423 for (char c : unsafe_arg) {424 if (escapables.contains(c))425 safe_arg.push_back('\\');426 safe_arg.push_back(c);427 }428 return safe_arg;429}430 431lldb::Encoding Args::StringToEncoding(llvm::StringRef s,432 lldb::Encoding fail_value) {433 return llvm::StringSwitch<lldb::Encoding>(s)434 .Case("uint", eEncodingUint)435 .Case("sint", eEncodingSint)436 .Case("ieee754", eEncodingIEEE754)437 .Case("vector", eEncodingVector)438 .Default(fail_value);439}440 441uint32_t Args::StringToGenericRegister(llvm::StringRef s) {442 if (s.empty())443 return LLDB_INVALID_REGNUM;444 uint32_t result = llvm::StringSwitch<uint32_t>(s)445 .Case("pc", LLDB_REGNUM_GENERIC_PC)446 .Case("sp", LLDB_REGNUM_GENERIC_SP)447 .Case("fp", LLDB_REGNUM_GENERIC_FP)448 .Cases({"ra", "lr"}, LLDB_REGNUM_GENERIC_RA)449 .Case("flags", LLDB_REGNUM_GENERIC_FLAGS)450 .Case("arg1", LLDB_REGNUM_GENERIC_ARG1)451 .Case("arg2", LLDB_REGNUM_GENERIC_ARG2)452 .Case("arg3", LLDB_REGNUM_GENERIC_ARG3)453 .Case("arg4", LLDB_REGNUM_GENERIC_ARG4)454 .Case("arg5", LLDB_REGNUM_GENERIC_ARG5)455 .Case("arg6", LLDB_REGNUM_GENERIC_ARG6)456 .Case("arg7", LLDB_REGNUM_GENERIC_ARG7)457 .Case("arg8", LLDB_REGNUM_GENERIC_ARG8)458 .Case("tp", LLDB_REGNUM_GENERIC_TP)459 .Default(LLDB_INVALID_REGNUM);460 return result;461}462 463void Args::EncodeEscapeSequences(const char *src, std::string &dst) {464 dst.clear();465 if (src) {466 for (const char *p = src; *p != '\0'; ++p) {467 size_t non_special_chars = ::strcspn(p, "\\");468 if (non_special_chars > 0) {469 dst.append(p, non_special_chars);470 p += non_special_chars;471 if (*p == '\0')472 break;473 }474 475 if (*p == '\\') {476 ++p; // skip the slash477 switch (*p) {478 case 'a':479 dst.append(1, '\a');480 break;481 case 'b':482 dst.append(1, '\b');483 break;484 case 'f':485 dst.append(1, '\f');486 break;487 case 'n':488 dst.append(1, '\n');489 break;490 case 'r':491 dst.append(1, '\r');492 break;493 case 't':494 dst.append(1, '\t');495 break;496 case 'v':497 dst.append(1, '\v');498 break;499 case '\\':500 dst.append(1, '\\');501 break;502 case '\'':503 dst.append(1, '\'');504 break;505 case '"':506 dst.append(1, '"');507 break;508 case '0':509 // 1 to 3 octal chars510 {511 // Make a string that can hold onto the initial zero char, up to 3512 // octal digits, and a terminating NULL.513 char oct_str[5] = {'\0', '\0', '\0', '\0', '\0'};514 515 int i;516 for (i = 0; (p[i] >= '0' && p[i] <= '7') && i < 4; ++i)517 oct_str[i] = p[i];518 519 // We don't want to consume the last octal character since the main520 // for loop will do this for us, so we advance p by one less than i521 // (even if i is zero)522 p += i - 1;523 unsigned long octal_value = ::strtoul(oct_str, nullptr, 8);524 if (octal_value <= UINT8_MAX) {525 dst.append(1, static_cast<char>(octal_value));526 }527 }528 break;529 530 case 'x':531 // hex number in the format532 if (isxdigit(p[1])) {533 ++p; // Skip the 'x'534 535 // Make a string that can hold onto two hex chars plus a536 // NULL terminator537 char hex_str[3] = {*p, '\0', '\0'};538 if (isxdigit(p[1])) {539 ++p; // Skip the first of the two hex chars540 hex_str[1] = *p;541 }542 543 unsigned long hex_value = strtoul(hex_str, nullptr, 16);544 if (hex_value <= UINT8_MAX)545 dst.append(1, static_cast<char>(hex_value));546 } else {547 dst.append(1, 'x');548 }549 break;550 551 default:552 // Just desensitize any other character by just printing what came553 // after the '\'554 dst.append(1, *p);555 break;556 }557 }558 }559 }560}561 562void Args::ExpandEscapedCharacters(const char *src, std::string &dst) {563 dst.clear();564 if (src) {565 for (const char *p = src; *p != '\0'; ++p) {566 if (llvm::isPrint(*p))567 dst.append(1, *p);568 else {569 switch (*p) {570 case '\a':571 dst.append("\\a");572 break;573 case '\b':574 dst.append("\\b");575 break;576 case '\f':577 dst.append("\\f");578 break;579 case '\n':580 dst.append("\\n");581 break;582 case '\r':583 dst.append("\\r");584 break;585 case '\t':586 dst.append("\\t");587 break;588 case '\v':589 dst.append("\\v");590 break;591 case '\'':592 dst.append("\\'");593 break;594 case '"':595 dst.append("\\\"");596 break;597 case '\\':598 dst.append("\\\\");599 break;600 default: {601 // Just encode as octal602 dst.append("\\0");603 char octal_str[32];604 snprintf(octal_str, sizeof(octal_str), "%o", *p);605 dst.append(octal_str);606 } break;607 }608 }609 }610 }611}612 613std::string Args::EscapeLLDBCommandArgument(const std::string &arg,614 char quote_char) {615 const char *chars_to_escape = nullptr;616 switch (quote_char) {617 case '\0':618 chars_to_escape = " \t\\'\"`";619 break;620 case '"':621 chars_to_escape = "$\"`\\";622 break;623 case '`':624 case '\'':625 return arg;626 default:627 assert(false && "Unhandled quote character");628 return arg;629 }630 631 std::string res;632 res.reserve(arg.size());633 for (char c : arg) {634 if (::strchr(chars_to_escape, c))635 res.push_back('\\');636 res.push_back(c);637 }638 return res;639}640 641OptionsWithRaw::OptionsWithRaw(llvm::StringRef arg_string) {642 SetFromString(arg_string);643}644 645void OptionsWithRaw::SetFromString(llvm::StringRef arg_string) {646 const llvm::StringRef original_args = arg_string;647 648 size_t shift;649 arg_string = ltrimForArgs(arg_string, shift);650 std::string arg;651 char quote;652 653 // If the string doesn't start with a dash, we just have no options and just654 // a raw part.655 if (!arg_string.starts_with("-")) {656 m_suffix = std::string(original_args);657 return;658 }659 660 bool found_suffix = false;661 while (!arg_string.empty()) {662 // The length of the prefix before parsing.663 std::size_t prev_prefix_length = original_args.size() - arg_string.size();664 665 // Parse the next argument from the remaining string.666 std::tie(arg, quote, arg_string) = ParseSingleArgument(arg_string);667 668 // If we get an unquoted '--' argument, then we reached the suffix part669 // of the command.670 Args::ArgEntry entry(arg, quote, std::nullopt);671 if (!entry.IsQuoted() && arg == "--") {672 // The remaining line is the raw suffix, and the line we parsed so far673 // needs to be interpreted as arguments.674 m_has_args = true;675 m_suffix = std::string(arg_string);676 found_suffix = true;677 678 // The length of the prefix after parsing.679 std::size_t prefix_length = original_args.size() - arg_string.size();680 681 // Take the string we know contains all the arguments and actually parse682 // it as proper arguments.683 llvm::StringRef prefix = original_args.take_front(prev_prefix_length);684 m_args = Args(prefix);685 m_arg_string = prefix;686 687 // We also record the part of the string that contains the arguments plus688 // the delimiter.689 m_arg_string_with_delimiter = original_args.take_front(prefix_length);690 691 // As the rest of the string became the raw suffix, we are done here.692 break;693 }694 695 arg_string = ltrimForArgs(arg_string, shift);696 }697 698 // If we didn't find a suffix delimiter, the whole string is the raw suffix.699 if (!found_suffix)700 m_suffix = std::string(original_args);701}702