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
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 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.
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(Chars: k_escapable_characters);
30 result += quoted.substr(Start: 0, N: regular);
31 quoted = quoted.substr(Start: 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(s: k_escapable_characters, c: 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 left
68// side of the string.
69static llvm::StringRef ltrimForArgs(llvm::StringRef str) {
70 static const char *k_space_separators = " \t";
71 return str.ltrim(Chars: 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.
79static std::tuple<std::string, char, llvm::StringRef>
80ParseSingleArgument(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(Chars: " \t\r\"'`\\");
98 arg += command.substr(Start: 0, N: regular);
99 command = command.substr(Start: 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(s: " \t\\'\"`", c: 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(quoted: command, result&: 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(C: special);
144 arg += command.substr(Start: 0, N: quoted);
145 command = command.substr(Start: 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(args&: arg, args&: first_quote_char, args&: command);
157}
158
159Args::ArgEntry::ArgEntry(llvm::StringRef str, char quote) : quote(quote) {
160 size_t size = str.size();
161 ptr.reset(p: new char[size + 1]);
162
163 ::memcpy(dest: data(), src: str.data() ? str.data() : "", n: size);
164 ptr[size] = 0;
165}
166
167// Args constructor
168Args::Args(llvm::StringRef command) { SetCommandString(command); }
169
170Args::Args(const Args &rhs) { *this = rhs; }
171
172Args::Args(const StringList &list) : Args() {
173 for (const std::string &arg : list)
174 AppendArgument(arg_str: arg);
175}
176
177Args::Args(llvm::ArrayRef<llvm::StringRef> args) : Args() {
178 for (llvm::StringRef arg : args)
179 AppendArgument(arg_str: arg);
180}
181
182Args &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(args: entry.ref(), args: entry.quote);
189 m_argv.push_back(x: m_entries.back().data());
190 }
191 m_argv.push_back(x: nullptr);
192 return *this;
193}
194
195// Destructor
196Args::~Args() = default;
197
198void 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(format: "{0}[{1}]=\"{2}\"\n", args&: label_name, args: i++, args: entry.ref());
206 }
207 s.Format(format: "{0}[{1}]=NULL\n", args&: label_name, args&: i);
208 s.EOL();
209}
210
211bool 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
228bool 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
247void Args::SetCommandString(llvm::StringRef command) {
248 Clear();
249 m_argv.clear();
250
251 command = ltrimForArgs(str: command);
252 std::string arg;
253 char quote;
254 while (!command.empty()) {
255 std::tie(args&: arg, args&: quote, args&: command) = ParseSingleArgument(command);
256 m_entries.emplace_back(args&: arg, args&: quote);
257 m_argv.push_back(x: m_entries.back().data());
258 command = ltrimForArgs(str: command);
259 }
260 m_argv.push_back(x: nullptr);
261}
262
263const char *Args::GetArgumentAtIndex(size_t idx) const {
264 if (idx < m_argv.size())
265 return m_argv[idx];
266 return nullptr;
267}
268
269char **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
279const 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
285void 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(position: m_argv.begin());
290 m_entries.erase(position: m_entries.begin());
291}
292
293void Args::Unshift(llvm::StringRef arg_str, char quote_char) {
294 InsertArgumentAtIndex(idx: 0, arg_str, quote_char);
295}
296
297void 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(args: entry.ref(), args: entry.quote);
303 m_argv.push_back(x: m_entries.back().data());
304 }
305 m_argv.push_back(x: nullptr);
306}
307
308void 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(args&: arg, args: '\0');
316 m_argv.push_back(x: m_entries.back().data());
317 }
318
319 m_argv.push_back(x: nullptr);
320}
321
322void Args::AppendArgument(llvm::StringRef arg_str, char quote_char) {
323 InsertArgumentAtIndex(idx: GetArgumentCount(), arg_str, quote_char);
324}
325
326void 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(position: m_entries.begin() + idx, args&: arg_str, args&: quote_char);
334 m_argv.insert(position: m_argv.begin() + idx, x: m_entries[idx].data());
335}
336
337void 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
349void Args::DeleteArgumentAtIndex(size_t idx) {
350 if (idx >= m_entries.size())
351 return;
352
353 m_argv.erase(position: m_argv.begin() + idx);
354 m_entries.erase(position: m_entries.begin() + idx);
355}
356
357void Args::SetArguments(size_t argc, const char **argv) {
358 Clear();
359
360 auto args = llvm::ArrayRef(argv, argc);
361 m_entries.resize(new_size: argc);
362 m_argv.resize(new_size: 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
374void Args::SetArguments(const char **argv) {
375 SetArguments(argc: ArgvToArgc(argv), argv);
376}
377
378void Args::Clear() {
379 m_entries.clear();
380 m_argv.clear();
381 m_argv.push_back(x: nullptr);
382}
383
384std::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[] = {{.m_basename: "bash", .m_escapables: " '\"<>()&;"},
392 {.m_basename: "fish", .m_escapables: " '\"<>()&\\|;"},
393 {.m_basename: "tcsh", .m_escapables: " '\"<>()&;"},
394 {.m_basename: "zsh", .m_escapables: " '\"<>()&;\\|"},
395 {.m_basename: "sh", .m_escapables: " '\"<>()&;"}};
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(res: 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: c))
415 safe_arg.push_back(c: '\\');
416 safe_arg.push_back(c: c);
417 }
418 return safe_arg;
419}
420
421lldb::Encoding Args::StringToEncoding(llvm::StringRef s,
422 lldb::Encoding fail_value) {
423 return llvm::StringSwitch<lldb::Encoding>(s)
424 .Case(S: "uint", Value: eEncodingUint)
425 .Case(S: "sint", Value: eEncodingSint)
426 .Case(S: "ieee754", Value: eEncodingIEEE754)
427 .Case(S: "vector", Value: eEncodingVector)
428 .Default(Value: fail_value);
429}
430
431uint32_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(S: "pc", LLDB_REGNUM_GENERIC_PC)
436 .Case(S: "sp", LLDB_REGNUM_GENERIC_SP)
437 .Case(S: "fp", LLDB_REGNUM_GENERIC_FP)
438 .Cases(S0: "ra", S1: "lr", LLDB_REGNUM_GENERIC_RA)
439 .Case(S: "flags", LLDB_REGNUM_GENERIC_FLAGS)
440 .Case(S: "arg1", LLDB_REGNUM_GENERIC_ARG1)
441 .Case(S: "arg2", LLDB_REGNUM_GENERIC_ARG2)
442 .Case(S: "arg3", LLDB_REGNUM_GENERIC_ARG3)
443 .Case(S: "arg4", LLDB_REGNUM_GENERIC_ARG4)
444 .Case(S: "arg5", LLDB_REGNUM_GENERIC_ARG5)
445 .Case(S: "arg6", LLDB_REGNUM_GENERIC_ARG6)
446 .Case(S: "arg7", LLDB_REGNUM_GENERIC_ARG7)
447 .Case(S: "arg8", LLDB_REGNUM_GENERIC_ARG8)
448 .Case(S: "tp", LLDB_REGNUM_GENERIC_TP)
449 .Default(LLDB_INVALID_REGNUM);
450 return result;
451}
452
453void 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(s: p, reject: "\\");
458 if (non_special_chars > 0) {
459 dst.append(s: p, n: 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(n: 1, c: '\a');
470 break;
471 case 'b':
472 dst.append(n: 1, c: '\b');
473 break;
474 case 'f':
475 dst.append(n: 1, c: '\f');
476 break;
477 case 'n':
478 dst.append(n: 1, c: '\n');
479 break;
480 case 'r':
481 dst.append(n: 1, c: '\r');
482 break;
483 case 't':
484 dst.append(n: 1, c: '\t');
485 break;
486 case 'v':
487 dst.append(n: 1, c: '\v');
488 break;
489 case '\\':
490 dst.append(n: 1, c: '\\');
491 break;
492 case '\'':
493 dst.append(n: 1, c: '\'');
494 break;
495 case '"':
496 dst.append(n: 1, c: '"');
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(nptr: oct_str, endptr: nullptr, base: 8);
514 if (octal_value <= UINT8_MAX) {
515 dst.append(n: 1, c: 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(nptr: hex_str, endptr: nullptr, base: 16);
534 if (hex_value <= UINT8_MAX)
535 dst.append(n: 1, c: static_cast<char>(hex_value));
536 } else {
537 dst.append(n: 1, c: 'x');
538 }
539 break;
540
541 default:
542 // Just desensitize any other character by just printing what came
543 // after the '\'
544 dst.append(n: 1, c: *p);
545 break;
546 }
547 }
548 }
549 }
550}
551
552void 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(C: *p))
557 dst.append(n: 1, c: *p);
558 else {
559 switch (*p) {
560 case '\a':
561 dst.append(s: "\\a");
562 break;
563 case '\b':
564 dst.append(s: "\\b");
565 break;
566 case '\f':
567 dst.append(s: "\\f");
568 break;
569 case '\n':
570 dst.append(s: "\\n");
571 break;
572 case '\r':
573 dst.append(s: "\\r");
574 break;
575 case '\t':
576 dst.append(s: "\\t");
577 break;
578 case '\v':
579 dst.append(s: "\\v");
580 break;
581 case '\'':
582 dst.append(s: "\\'");
583 break;
584 case '"':
585 dst.append(s: "\\\"");
586 break;
587 case '\\':
588 dst.append(s: "\\\\");
589 break;
590 default: {
591 // Just encode as octal
592 dst.append(s: "\\0");
593 char octal_str[32];
594 snprintf(s: octal_str, maxlen: sizeof(octal_str), format: "%o", *p);
595 dst.append(s: octal_str);
596 } break;
597 }
598 }
599 }
600 }
601}
602
603std::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(res: arg.size());
623 for (char c : arg) {
624 if (::strchr(s: chars_to_escape, c: c))
625 res.push_back(c: '\\');
626 res.push_back(c: c);
627 }
628 return res;
629}
630
631OptionsWithRaw::OptionsWithRaw(llvm::StringRef arg_string) {
632 SetFromString(arg_string);
633}
634
635void OptionsWithRaw::SetFromString(llvm::StringRef arg_string) {
636 const llvm::StringRef original_args = arg_string;
637
638 arg_string = ltrimForArgs(str: 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(Prefix: "-")) {
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(args&: arg, args&: quote, args&: arg_string) = ParseSingleArgument(command: 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(N: 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(N: 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(str: 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

source code of lldb/source/Utility/Args.cpp