xref: /freebsd/contrib/llvm-project/llvm/lib/Option/Option.cpp (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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/ADT/StringRef.h"
10 #include "llvm/ADT/Twine.h"
11 #include "llvm/Config/llvm-config.h"
12 #include "llvm/Option/Arg.h"
13 #include "llvm/Option/ArgList.h"
14 #include "llvm/Option/Option.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 #include <cstring>
22 
23 using namespace llvm;
24 using namespace llvm::opt;
25 
26 Option::Option(const OptTable::Info *info, const OptTable *owner)
27   : Info(info), Owner(owner) {
28   // Multi-level aliases are not supported. This just simplifies option
29   // tracking, it is not an inherent limitation.
30   assert((!Info || !getAlias().isValid() || !getAlias().getAlias().isValid()) &&
31          "Multi-level aliases are not supported.");
32 
33   if (Info && getAliasArgs()) {
34     assert(getAlias().isValid() && "Only alias options can have alias args.");
35     assert(getKind() == FlagClass && "Only Flag aliases can have alias args.");
36     assert(getAlias().getKind() != FlagClass &&
37            "Cannot provide alias args to a flag option.");
38   }
39 }
40 
41 void Option::print(raw_ostream &O) const {
42   O << "<";
43   switch (getKind()) {
44 #define P(N) case N: O << #N; break
45     P(GroupClass);
46     P(InputClass);
47     P(UnknownClass);
48     P(FlagClass);
49     P(JoinedClass);
50     P(ValuesClass);
51     P(SeparateClass);
52     P(CommaJoinedClass);
53     P(MultiArgClass);
54     P(JoinedOrSeparateClass);
55     P(JoinedAndSeparateClass);
56     P(RemainingArgsClass);
57     P(RemainingArgsJoinedClass);
58 #undef P
59   }
60 
61   if (Info->Prefixes) {
62     O << " Prefixes:[";
63     for (const char *const *Pre = Info->Prefixes; *Pre != nullptr; ++Pre) {
64       O << '"' << *Pre << (*(Pre + 1) == nullptr ? "\"" : "\", ");
65     }
66     O << ']';
67   }
68 
69   O << " Name:\"" << getName() << '"';
70 
71   const Option Group = getGroup();
72   if (Group.isValid()) {
73     O << " Group:";
74     Group.print(O);
75   }
76 
77   const Option Alias = getAlias();
78   if (Alias.isValid()) {
79     O << " Alias:";
80     Alias.print(O);
81   }
82 
83   if (getKind() == MultiArgClass)
84     O << " NumArgs:" << getNumArgs();
85 
86   O << ">\n";
87 }
88 
89 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
90 LLVM_DUMP_METHOD void Option::dump() const { print(dbgs()); }
91 #endif
92 
93 bool Option::matches(OptSpecifier Opt) const {
94   // Aliases are never considered in matching, look through them.
95   const Option Alias = getAlias();
96   if (Alias.isValid())
97     return Alias.matches(Opt);
98 
99   // Check exact match.
100   if (getID() == Opt.getID())
101     return true;
102 
103   const Option Group = getGroup();
104   if (Group.isValid())
105     return Group.matches(Opt);
106   return false;
107 }
108 
109 Arg *Option::acceptInternal(const ArgList &Args, unsigned &Index,
110                             unsigned ArgSize) const {
111   StringRef Spelling = StringRef(Args.getArgString(Index), ArgSize);
112   switch (getKind()) {
113   case FlagClass: {
114     if (ArgSize != strlen(Args.getArgString(Index)))
115       return nullptr;
116     return new Arg(*this, Spelling, Index++);
117   }
118   case JoinedClass: {
119     const char *Value = Args.getArgString(Index) + ArgSize;
120     return new Arg(*this, Spelling, Index++, Value);
121   }
122   case CommaJoinedClass: {
123     // Always matches.
124     const char *Str = Args.getArgString(Index) + ArgSize;
125     Arg *A = new Arg(*this, Spelling, Index++);
126 
127     // Parse out the comma separated values.
128     const char *Prev = Str;
129     for (;; ++Str) {
130       char c = *Str;
131 
132       if (!c || c == ',') {
133         if (Prev != Str) {
134           char *Value = new char[Str - Prev + 1];
135           memcpy(Value, Prev, Str - Prev);
136           Value[Str - Prev] = '\0';
137           A->getValues().push_back(Value);
138         }
139 
140         if (!c)
141           break;
142 
143         Prev = Str + 1;
144       }
145     }
146     A->setOwnsValues(true);
147 
148     return A;
149   }
150   case SeparateClass:
151     // Matches iff this is an exact match.
152     // FIXME: Avoid strlen.
153     if (ArgSize != strlen(Args.getArgString(Index)))
154       return nullptr;
155 
156     Index += 2;
157     if (Index > Args.getNumInputArgStrings() ||
158         Args.getArgString(Index - 1) == nullptr)
159       return nullptr;
160 
161     return new Arg(*this, Spelling, Index - 2, Args.getArgString(Index - 1));
162   case MultiArgClass: {
163     // Matches iff this is an exact match.
164     // FIXME: Avoid strlen.
165     if (ArgSize != strlen(Args.getArgString(Index)))
166       return nullptr;
167 
168     Index += 1 + getNumArgs();
169     if (Index > Args.getNumInputArgStrings())
170       return nullptr;
171 
172     Arg *A = new Arg(*this, Spelling, Index - 1 - getNumArgs(),
173                      Args.getArgString(Index - getNumArgs()));
174     for (unsigned i = 1; i != getNumArgs(); ++i)
175       A->getValues().push_back(Args.getArgString(Index - getNumArgs() + i));
176     return A;
177   }
178   case JoinedOrSeparateClass: {
179     // If this is not an exact match, it is a joined arg.
180     // FIXME: Avoid strlen.
181     if (ArgSize != strlen(Args.getArgString(Index))) {
182       const char *Value = Args.getArgString(Index) + ArgSize;
183       return new Arg(*this, Spelling, Index++, Value);
184     }
185 
186     // Otherwise it must be separate.
187     Index += 2;
188     if (Index > Args.getNumInputArgStrings() ||
189         Args.getArgString(Index - 1) == nullptr)
190       return nullptr;
191 
192     return new Arg(*this, Spelling, Index - 2, Args.getArgString(Index - 1));
193   }
194   case JoinedAndSeparateClass:
195     // Always matches.
196     Index += 2;
197     if (Index > Args.getNumInputArgStrings() ||
198         Args.getArgString(Index - 1) == nullptr)
199       return nullptr;
200 
201     return new Arg(*this, Spelling, Index - 2,
202                    Args.getArgString(Index - 2) + ArgSize,
203                    Args.getArgString(Index - 1));
204   case RemainingArgsClass: {
205     // Matches iff this is an exact match.
206     // FIXME: Avoid strlen.
207     if (ArgSize != strlen(Args.getArgString(Index)))
208       return nullptr;
209     Arg *A = new Arg(*this, Spelling, Index++);
210     while (Index < Args.getNumInputArgStrings() &&
211            Args.getArgString(Index) != nullptr)
212       A->getValues().push_back(Args.getArgString(Index++));
213     return A;
214   }
215   case RemainingArgsJoinedClass: {
216     Arg *A = new Arg(*this, Spelling, Index);
217     if (ArgSize != strlen(Args.getArgString(Index))) {
218       // An inexact match means there is a joined arg.
219       A->getValues().push_back(Args.getArgString(Index) + ArgSize);
220     }
221     Index++;
222     while (Index < Args.getNumInputArgStrings() &&
223            Args.getArgString(Index) != nullptr)
224       A->getValues().push_back(Args.getArgString(Index++));
225     return A;
226   }
227 
228   default:
229     llvm_unreachable("Invalid option kind!");
230   }
231 }
232 
233 Arg *Option::accept(const ArgList &Args,
234                     unsigned &Index,
235                     unsigned ArgSize) const {
236   std::unique_ptr<Arg> A(acceptInternal(Args, Index, ArgSize));
237   if (!A)
238     return nullptr;
239 
240   const Option &UnaliasedOption = getUnaliasedOption();
241   if (getID() == UnaliasedOption.getID())
242     return A.release();
243 
244   // "A" is an alias for a different flag. For most clients it's more convenient
245   // if this function returns unaliased Args, so create an unaliased arg for
246   // returning.
247 
248   // This creates a completely new Arg object for the unaliased Arg because
249   // the alias and the unaliased arg can have different Kinds and different
250   // Values (due to AliasArgs<>).
251 
252   // Get the spelling from the unaliased option.
253   StringRef UnaliasedSpelling = Args.MakeArgString(
254       Twine(UnaliasedOption.getPrefix()) + Twine(UnaliasedOption.getName()));
255 
256   // It's a bit weird that aliased and unaliased arg share one index, but
257   // the index is mostly use as a memory optimization in render().
258   // Due to this, ArgList::getArgString(A->getIndex()) will return the spelling
259   // of the aliased arg always, while A->getSpelling() returns either the
260   // unaliased or the aliased arg, depending on which Arg object it's called on.
261   Arg *UnaliasedA = new Arg(UnaliasedOption, UnaliasedSpelling, A->getIndex());
262   Arg *RawA = A.get();
263   UnaliasedA->setAlias(std::move(A));
264 
265   if (getKind() != FlagClass) {
266     // Values are usually owned by the ArgList. The exception are
267     // CommaJoined flags, where the Arg owns the values. For aliased flags,
268     // make the unaliased Arg the owner of the values.
269     // FIXME: There aren't many uses of CommaJoined -- try removing
270     // CommaJoined in favor of just calling StringRef::split(',') instead.
271     UnaliasedA->getValues() = RawA->getValues();
272     UnaliasedA->setOwnsValues(RawA->getOwnsValues());
273     RawA->setOwnsValues(false);
274     return UnaliasedA;
275   }
276 
277   // FlagClass aliases can have AliasArgs<>; add those to the unaliased arg.
278   if (const char *Val = getAliasArgs()) {
279     while (*Val != '\0') {
280       UnaliasedA->getValues().push_back(Val);
281 
282       // Move past the '\0' to the next argument.
283       Val += strlen(Val) + 1;
284     }
285   }
286   if (UnaliasedOption.getKind() == JoinedClass && !getAliasArgs())
287     // A Flag alias for a Joined option must provide an argument.
288     UnaliasedA->getValues().push_back("");
289   return UnaliasedA;
290 }
291