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, size_t &shift) {
70 static const char *k_space_separators = " \t";
71 llvm::StringRef result = str.ltrim(Chars: 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 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 regular characters and append them.
99 size_t regular = command.find_first_of(Chars: " \t\r\"'`\\");
100 arg += command.substr(Start: 0, N: regular);
101 command = command.substr(Start: 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 escapable
116 // character, we leave the character sequence untouched.
117 if (strchr(s: " \t\\'\"`", c: 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(quoted: command, result&: arg);
142 else {
143 // For single quotes, we simply skip ahead to the matching quote
144 // character (or the end of the string).
145 size_t quoted = command.find(C: special);
146 arg += command.substr(Start: 0, N: quoted);
147 command = command.substr(Start: 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(args&: arg, args&: first_quote_char, args&: 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(p: new char[size + 1]);
166
167 ::memcpy(dest: data(), src: str.data() ? str.data() : "", n: size);
168 ptr[size] = 0;
169}
170
171// Args constructor
172Args::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_str: arg);
179}
180
181Args::Args(llvm::ArrayRef<llvm::StringRef> args) : Args() {
182 for (llvm::StringRef arg : args)
183 AppendArgument(arg_str: 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(args: entry.ref(), args: entry.quote, args: entry.column);
193 m_argv.push_back(x: m_entries.back().data());
194 }
195 m_argv.push_back(x: nullptr);
196 return *this;
197}
198
199// Destructor
200Args::~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(format: "{0}[{1}]=\"{2}\"\n", args&: label_name, args: i++, args: entry.ref());
210 }
211 s.Format(format: "{0}[{1}]=NULL\n", args&: label_name, args&: 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(str: 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(args&: arg, args&: quote, args&: command) = ParseSingleArgument(command);
264 m_entries.emplace_back(args&: arg, args&: quote, args&: column);
265 m_argv.push_back(x: m_entries.back().data());
266 command = ltrimForArgs(str: command, shift);
267 column += shift;
268 column += command.data() - prev;
269 }
270 m_argv.push_back(x: 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 behavior
282 // 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 acting
284 // this way for some time, so it makes sense to leave it this way until
285 // 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 array
297 if (m_entries.empty())
298 return;
299 m_argv.erase(position: m_argv.begin());
300 m_entries.erase(position: m_entries.begin());
301}
302
303void Args::Unshift(llvm::StringRef arg_str, char quote_char) {
304 InsertArgumentAtIndex(idx: 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(args: entry.ref(), args: entry.quote, args: entry.column);
313 m_argv.push_back(x: m_entries.back().data());
314 }
315 m_argv.push_back(x: 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(args&: arg, args: '\0', args: std::nullopt);
326 m_argv.push_back(x: m_entries.back().data());
327 }
328
329 m_argv.push_back(x: nullptr);
330}
331
332void Args::AppendArgument(llvm::StringRef arg_str, char quote_char) {
333 InsertArgumentAtIndex(idx: 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(position: m_entries.begin() + idx, args&: arg_str, args&: quote_char, args: std::nullopt);
344 m_argv.insert(position: m_argv.begin() + idx, x: 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(position: m_argv.begin() + idx);
364 m_entries.erase(position: 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(new_size: argc);
372 m_argv.resize(new_size: 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(argc: ArgvToArgc(argv), argv);
386}
387
388void Args::Clear() {
389 m_entries.clear();
390 m_argv.clear();
391 m_argv.push_back(x: 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[] = {{.m_basename: "bash", .m_escapables: " '\"<>()&;"},
402 {.m_basename: "fish", .m_escapables: " '\"<>()&\\|;"},
403 {.m_basename: "tcsh", .m_escapables: " '\"<>()&;"},
404 {.m_basename: "zsh", .m_escapables: " '\"<>()&;\\|"},
405 {.m_basename: "sh", .m_escapables: " '\"<>()&;"}};
406
407 // safe minimal set
408 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(res: 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: c))
425 safe_arg.push_back(c: '\\');
426 safe_arg.push_back(c: 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(S: "uint", Value: eEncodingUint)
435 .Case(S: "sint", Value: eEncodingSint)
436 .Case(S: "ieee754", Value: eEncodingIEEE754)
437 .Case(S: "vector", Value: eEncodingVector)
438 .Default(Value: 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(S: "pc", LLDB_REGNUM_GENERIC_PC)
446 .Case(S: "sp", LLDB_REGNUM_GENERIC_SP)
447 .Case(S: "fp", LLDB_REGNUM_GENERIC_FP)
448 .Cases(S0: "ra", S1: "lr", LLDB_REGNUM_GENERIC_RA)
449 .Case(S: "flags", LLDB_REGNUM_GENERIC_FLAGS)
450 .Case(S: "arg1", LLDB_REGNUM_GENERIC_ARG1)
451 .Case(S: "arg2", LLDB_REGNUM_GENERIC_ARG2)
452 .Case(S: "arg3", LLDB_REGNUM_GENERIC_ARG3)
453 .Case(S: "arg4", LLDB_REGNUM_GENERIC_ARG4)
454 .Case(S: "arg5", LLDB_REGNUM_GENERIC_ARG5)
455 .Case(S: "arg6", LLDB_REGNUM_GENERIC_ARG6)
456 .Case(S: "arg7", LLDB_REGNUM_GENERIC_ARG7)
457 .Case(S: "arg8", LLDB_REGNUM_GENERIC_ARG8)
458 .Case(S: "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(s: p, reject: "\\");
468 if (non_special_chars > 0) {
469 dst.append(s: p, n: non_special_chars);
470 p += non_special_chars;
471 if (*p == '\0')
472 break;
473 }
474
475 if (*p == '\\') {
476 ++p; // skip the slash
477 switch (*p) {
478 case 'a':
479 dst.append(n: 1, c: '\a');
480 break;
481 case 'b':
482 dst.append(n: 1, c: '\b');
483 break;
484 case 'f':
485 dst.append(n: 1, c: '\f');
486 break;
487 case 'n':
488 dst.append(n: 1, c: '\n');
489 break;
490 case 'r':
491 dst.append(n: 1, c: '\r');
492 break;
493 case 't':
494 dst.append(n: 1, c: '\t');
495 break;
496 case 'v':
497 dst.append(n: 1, c: '\v');
498 break;
499 case '\\':
500 dst.append(n: 1, c: '\\');
501 break;
502 case '\'':
503 dst.append(n: 1, c: '\'');
504 break;
505 case '"':
506 dst.append(n: 1, c: '"');
507 break;
508 case '0':
509 // 1 to 3 octal chars
510 {
511 // Make a string that can hold onto the initial zero char, up to 3
512 // 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 main
520 // for loop will do this for us, so we advance p by one less than i
521 // (even if i is zero)
522 p += i - 1;
523 unsigned long octal_value = ::strtoul(nptr: oct_str, endptr: nullptr, base: 8);
524 if (octal_value <= UINT8_MAX) {
525 dst.append(n: 1, c: static_cast<char>(octal_value));
526 }
527 }
528 break;
529
530 case 'x':
531 // hex number in the format
532 if (isxdigit(p[1])) {
533 ++p; // Skip the 'x'
534
535 // Make a string that can hold onto two hex chars plus a
536 // NULL terminator
537 char hex_str[3] = {*p, '\0', '\0'};
538 if (isxdigit(p[1])) {
539 ++p; // Skip the first of the two hex chars
540 hex_str[1] = *p;
541 }
542
543 unsigned long hex_value = strtoul(nptr: hex_str, endptr: nullptr, base: 16);
544 if (hex_value <= UINT8_MAX)
545 dst.append(n: 1, c: static_cast<char>(hex_value));
546 } else {
547 dst.append(n: 1, c: 'x');
548 }
549 break;
550
551 default:
552 // Just desensitize any other character by just printing what came
553 // after the '\'
554 dst.append(n: 1, c: *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(C: *p))
567 dst.append(n: 1, c: *p);
568 else {
569 switch (*p) {
570 case '\a':
571 dst.append(s: "\\a");
572 break;
573 case '\b':
574 dst.append(s: "\\b");
575 break;
576 case '\f':
577 dst.append(s: "\\f");
578 break;
579 case '\n':
580 dst.append(s: "\\n");
581 break;
582 case '\r':
583 dst.append(s: "\\r");
584 break;
585 case '\t':
586 dst.append(s: "\\t");
587 break;
588 case '\v':
589 dst.append(s: "\\v");
590 break;
591 case '\'':
592 dst.append(s: "\\'");
593 break;
594 case '"':
595 dst.append(s: "\\\"");
596 break;
597 case '\\':
598 dst.append(s: "\\\\");
599 break;
600 default: {
601 // Just encode as octal
602 dst.append(s: "\\0");
603 char octal_str[32];
604 snprintf(s: octal_str, maxlen: sizeof(octal_str), format: "%o", *p);
605 dst.append(s: 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(res: arg.size());
633 for (char c : arg) {
634 if (::strchr(s: chars_to_escape, c: c))
635 res.push_back(c: '\\');
636 res.push_back(c: 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(str: 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 just
654 // a raw part.
655 if (!arg_string.starts_with(Prefix: "-")) {
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(args&: arg, args&: quote, args&: arg_string) = ParseSingleArgument(command: arg_string);
667
668 // If we get an unquoted '--' argument, then we reached the suffix part
669 // 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 far
673 // 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 parse
682 // it as proper arguments.
683 llvm::StringRef prefix = original_args.take_front(N: 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 plus
688 // the delimiter.
689 m_arg_string_with_delimiter = original_args.take_front(N: 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(str: 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

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