xref: /llvm-project/llvm/lib/Option/Option.cpp (revision dd647e3e608ed0b2bac7c588d5859b80ef4a5976)
1 //===- Option.cpp - Abstract Driver Options -------------------------------===//
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 "llvm/Option/Option.h"
10 #include "llvm/ADT/StringRef.h"
11 #include "llvm/ADT/Twine.h"
12 #include "llvm/Config/llvm-config.h"
13 #include "llvm/Option/Arg.h"
14 #include "llvm/Option/ArgList.h"
15 #include "llvm/Option/OptTable.h"
16 #include "llvm/Support/Compiler.h"
17 #include "llvm/Support/Debug.h"
18 #include "llvm/Support/ErrorHandling.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <cassert>
21 
22 using namespace llvm;
23 using namespace llvm::opt;
24 
25 Option::Option(const OptTable::Info *info, const OptTable *owner)
26   : Info(info), Owner(owner) {
27   // Multi-level aliases are not supported. This just simplifies option
28   // tracking, it is not an inherent limitation.
29   assert((!Info || !getAlias().isValid() || !getAlias().getAlias().isValid()) &&
30          "Multi-level aliases are not supported.");
31 
32   if (Info && getAliasArgs()) {
33     assert(getAlias().isValid() && "Only alias options can have alias args.");
34     assert(getKind() == FlagClass && "Only Flag aliases can have alias args.");
35     assert(getAlias().getKind() != FlagClass &&
36            "Cannot provide alias args to a flag option.");
37   }
38 }
39 
40 void Option::print(raw_ostream &O, bool AddNewLine) const {
41   O << "<";
42   switch (getKind()) {
43 #define P(N) case N: O << #N; break
44     P(GroupClass);
45     P(InputClass);
46     P(UnknownClass);
47     P(FlagClass);
48     P(JoinedClass);
49     P(ValuesClass);
50     P(SeparateClass);
51     P(CommaJoinedClass);
52     P(MultiArgClass);
53     P(JoinedOrSeparateClass);
54     P(JoinedAndSeparateClass);
55     P(RemainingArgsClass);
56     P(RemainingArgsJoinedClass);
57 #undef P
58   }
59 
60   if (!Info->hasNoPrefix()) {
61     O << " Prefixes:[";
62     for (size_t I = 0, N = Info->getNumPrefixes(Owner->getPrefixesTable());
63          I != N; ++I)
64       O << '"'
65         << Info->getPrefix(Owner->getStrTable(), Owner->getPrefixesTable(), I)
66         << (I == N - 1 ? "\"" : "\", ");
67     O << ']';
68   }
69 
70   O << " Name:\"" << getName() << '"';
71 
72   const Option Group = getGroup();
73   if (Group.isValid()) {
74     O << " Group:";
75     Group.print(O, /*AddNewLine=*/false);
76   }
77 
78   const Option Alias = getAlias();
79   if (Alias.isValid()) {
80     O << " Alias:";
81     Alias.print(O, /*AddNewLine=*/false);
82   }
83 
84   if (getKind() == MultiArgClass)
85     O << " NumArgs:" << getNumArgs();
86 
87   O << ">";
88   if (AddNewLine)
89     O << "\n";
90 }
91 
92 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
93 LLVM_DUMP_METHOD void Option::dump() const { print(dbgs()); }
94 #endif
95 
96 bool Option::matches(OptSpecifier Opt) const {
97   // Aliases are never considered in matching, look through them.
98   const Option Alias = getAlias();
99   if (Alias.isValid())
100     return Alias.matches(Opt);
101 
102   // Check exact match.
103   if (getID() == Opt.getID())
104     return true;
105 
106   const Option Group = getGroup();
107   if (Group.isValid())
108     return Group.matches(Opt);
109   return false;
110 }
111 
112 std::unique_ptr<Arg> Option::acceptInternal(const ArgList &Args,
113                                             StringRef Spelling,
114                                             unsigned &Index) const {
115   const size_t SpellingSize = Spelling.size();
116   const size_t ArgStringSize = StringRef(Args.getArgString(Index)).size();
117   switch (getKind()) {
118   case FlagClass: {
119     if (SpellingSize != ArgStringSize)
120       return nullptr;
121     return std::make_unique<Arg>(*this, Spelling, Index++);
122   }
123   case JoinedClass: {
124     const char *Value = Args.getArgString(Index) + SpellingSize;
125     return std::make_unique<Arg>(*this, Spelling, Index++, Value);
126   }
127   case CommaJoinedClass: {
128     // Always matches.
129     const char *Str = Args.getArgString(Index) + SpellingSize;
130     auto A = std::make_unique<Arg>(*this, Spelling, Index++);
131 
132     // Parse out the comma separated values.
133     const char *Prev = Str;
134     for (;; ++Str) {
135       char c = *Str;
136 
137       if (!c || c == ',') {
138         if (Prev != Str) {
139           char *Value = new char[Str - Prev + 1];
140           memcpy(Value, Prev, Str - Prev);
141           Value[Str - Prev] = '\0';
142           A->getValues().push_back(Value);
143         }
144 
145         if (!c)
146           break;
147 
148         Prev = Str + 1;
149       }
150     }
151     A->setOwnsValues(true);
152 
153     return A;
154   }
155   case SeparateClass:
156     // Matches iff this is an exact match.
157     if (SpellingSize != ArgStringSize)
158       return nullptr;
159 
160     Index += 2;
161     if (Index > Args.getNumInputArgStrings() ||
162         Args.getArgString(Index - 1) == nullptr)
163       return nullptr;
164 
165     return std::make_unique<Arg>(*this, Spelling, Index - 2,
166                                  Args.getArgString(Index - 1));
167   case MultiArgClass: {
168     // Matches iff this is an exact match.
169     if (SpellingSize != ArgStringSize)
170       return nullptr;
171 
172     Index += 1 + getNumArgs();
173     if (Index > Args.getNumInputArgStrings())
174       return nullptr;
175 
176     auto A = std::make_unique<Arg>(*this, Spelling, Index - 1 - getNumArgs(),
177                                    Args.getArgString(Index - getNumArgs()));
178     for (unsigned i = 1; i != getNumArgs(); ++i)
179       A->getValues().push_back(Args.getArgString(Index - getNumArgs() + i));
180     return A;
181   }
182   case JoinedOrSeparateClass: {
183     // If this is not an exact match, it is a joined arg.
184     if (SpellingSize != ArgStringSize) {
185       const char *Value = Args.getArgString(Index) + SpellingSize;
186       return std::make_unique<Arg>(*this, Spelling, Index++, Value);
187     }
188 
189     // Otherwise it must be separate.
190     Index += 2;
191     if (Index > Args.getNumInputArgStrings() ||
192         Args.getArgString(Index - 1) == nullptr)
193       return nullptr;
194 
195     return std::make_unique<Arg>(*this, Spelling, Index - 2,
196                                  Args.getArgString(Index - 1));
197   }
198   case JoinedAndSeparateClass:
199     // Always matches.
200     Index += 2;
201     if (Index > Args.getNumInputArgStrings() ||
202         Args.getArgString(Index - 1) == nullptr)
203       return nullptr;
204 
205     return std::make_unique<Arg>(*this, Spelling, Index - 2,
206                                  Args.getArgString(Index - 2) + SpellingSize,
207                                  Args.getArgString(Index - 1));
208   case RemainingArgsClass: {
209     // Matches iff this is an exact match.
210     if (SpellingSize != ArgStringSize)
211       return nullptr;
212     auto A = std::make_unique<Arg>(*this, Spelling, Index++);
213     while (Index < Args.getNumInputArgStrings() &&
214            Args.getArgString(Index) != nullptr)
215       A->getValues().push_back(Args.getArgString(Index++));
216     return A;
217   }
218   case RemainingArgsJoinedClass: {
219     auto A = std::make_unique<Arg>(*this, Spelling, Index);
220     if (SpellingSize != ArgStringSize) {
221       // An inexact match means there is a joined arg.
222       A->getValues().push_back(Args.getArgString(Index) + SpellingSize);
223     }
224     Index++;
225     while (Index < Args.getNumInputArgStrings() &&
226            Args.getArgString(Index) != nullptr)
227       A->getValues().push_back(Args.getArgString(Index++));
228     return A;
229   }
230 
231   default:
232     llvm_unreachable("Invalid option kind!");
233   }
234 }
235 
236 std::unique_ptr<Arg> Option::accept(const ArgList &Args, StringRef CurArg,
237                                     bool GroupedShortOption,
238                                     unsigned &Index) const {
239   auto A(GroupedShortOption && getKind() == FlagClass
240                              ? std::make_unique<Arg>(*this, CurArg, Index)
241                              : acceptInternal(Args, CurArg, Index));
242   if (!A)
243     return nullptr;
244 
245   const Option &UnaliasedOption = getUnaliasedOption();
246   if (getID() == UnaliasedOption.getID())
247     return A;
248 
249   // "A" is an alias for a different flag. For most clients it's more convenient
250   // if this function returns unaliased Args, so create an unaliased arg for
251   // returning.
252 
253   // This creates a completely new Arg object for the unaliased Arg because
254   // the alias and the unaliased arg can have different Kinds and different
255   // Values (due to AliasArgs<>).
256 
257   // Get the spelling from the unaliased option.
258   StringRef UnaliasedSpelling = Args.MakeArgString(
259       Twine(UnaliasedOption.getPrefix()) + Twine(UnaliasedOption.getName()));
260 
261   // It's a bit weird that aliased and unaliased arg share one index, but
262   // the index is mostly use as a memory optimization in render().
263   // Due to this, ArgList::getArgString(A->getIndex()) will return the spelling
264   // of the aliased arg always, while A->getSpelling() returns either the
265   // unaliased or the aliased arg, depending on which Arg object it's called on.
266   auto UnaliasedA =
267       std::make_unique<Arg>(UnaliasedOption, UnaliasedSpelling, A->getIndex());
268   Arg *RawA = A.get();
269   UnaliasedA->setAlias(std::move(A));
270 
271   if (getKind() != FlagClass) {
272     // Values are usually owned by the ArgList. The exception are
273     // CommaJoined flags, where the Arg owns the values. For aliased flags,
274     // make the unaliased Arg the owner of the values.
275     // FIXME: There aren't many uses of CommaJoined -- try removing
276     // CommaJoined in favor of just calling StringRef::split(',') instead.
277     UnaliasedA->getValues() = RawA->getValues();
278     UnaliasedA->setOwnsValues(RawA->getOwnsValues());
279     RawA->setOwnsValues(false);
280     return UnaliasedA;
281   }
282 
283   // FlagClass aliases can have AliasArgs<>; add those to the unaliased arg.
284   if (const char *Val = getAliasArgs()) {
285     while (*Val != '\0') {
286       UnaliasedA->getValues().push_back(Val);
287 
288       // Move past the '\0' to the next argument.
289       Val += strlen(Val) + 1;
290     }
291   }
292   if (UnaliasedOption.getKind() == JoinedClass && !getAliasArgs())
293     // A Flag alias for a Joined option must provide an argument.
294     UnaliasedA->getValues().push_back("");
295   return UnaliasedA;
296 }
297