1 //===- DriverUtils.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 "Driver.h"
10 #include "InputFiles.h"
11 
12 #include "lld/Common/Args.h"
13 #include "lld/Common/ErrorHandler.h"
14 #include "lld/Common/Memory.h"
15 #include "lld/Common/Reproduce.h"
16 #include "llvm/Option/Arg.h"
17 #include "llvm/Option/ArgList.h"
18 #include "llvm/Option/Option.h"
19 #include "llvm/Support/CommandLine.h"
20 #include "llvm/Support/Path.h"
21 #include "llvm/TextAPI/MachO/TextAPIReader.h"
22 
23 using namespace llvm;
24 using namespace llvm::MachO;
25 using namespace llvm::opt;
26 using namespace llvm::sys;
27 using namespace lld;
28 using namespace lld::macho;
29 
30 // Create prefix string literals used in Options.td
31 #define PREFIX(NAME, VALUE) const char *NAME[] = VALUE;
32 #include "Options.inc"
33 #undef PREFIX
34 
35 // Create table mapping all options defined in Options.td
36 static const opt::OptTable::Info optInfo[] = {
37 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12)      \
38   {X1, X2, X10,         X11,         OPT_##ID, opt::Option::KIND##Class,       \
39    X9, X8, OPT_##GROUP, OPT_##ALIAS, X7,       X12},
40 #include "Options.inc"
41 #undef OPTION
42 };
43 
44 MachOOptTable::MachOOptTable() : OptTable(optInfo) {}
45 
46 // Set color diagnostics according to --color-diagnostics={auto,always,never}
47 // or --no-color-diagnostics flags.
48 static void handleColorDiagnostics(opt::InputArgList &args) {
49   auto *arg = args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
50                               OPT_no_color_diagnostics);
51   if (!arg)
52     return;
53   if (arg->getOption().getID() == OPT_color_diagnostics) {
54     lld::errs().enable_colors(true);
55   } else if (arg->getOption().getID() == OPT_no_color_diagnostics) {
56     lld::errs().enable_colors(false);
57   } else {
58     StringRef s = arg->getValue();
59     if (s == "always")
60       lld::errs().enable_colors(true);
61     else if (s == "never")
62       lld::errs().enable_colors(false);
63     else if (s != "auto")
64       error("unknown option: --color-diagnostics=" + s);
65   }
66 }
67 
68 opt::InputArgList MachOOptTable::parse(ArrayRef<const char *> argv) {
69   // Make InputArgList from string vectors.
70   unsigned missingIndex;
71   unsigned missingCount;
72   SmallVector<const char *, 256> vec(argv.data(), argv.data() + argv.size());
73 
74   // Expand response files (arguments in the form of @<filename>)
75   // and then parse the argument again.
76   cl::ExpandResponseFiles(saver, cl::TokenizeGNUCommandLine, vec);
77   opt::InputArgList args = ParseArgs(vec, missingIndex, missingCount);
78 
79   // Handle -fatal_warnings early since it converts missing argument warnings
80   // to errors.
81   errorHandler().fatalWarnings = args.hasArg(OPT_fatal_warnings);
82 
83   if (missingCount)
84     error(Twine(args.getArgString(missingIndex)) + ": missing argument");
85 
86   handleColorDiagnostics(args);
87 
88   for (opt::Arg *arg : args.filtered(OPT_UNKNOWN)) {
89     std::string nearest;
90     if (findNearest(arg->getAsString(args), nearest) > 1)
91       error("unknown argument '" + arg->getAsString(args) + "'");
92     else
93       error("unknown argument '" + arg->getAsString(args) +
94             "', did you mean '" + nearest + "'");
95   }
96   return args;
97 }
98 
99 void MachOOptTable::printHelp(const char *argv0, bool showHidden) const {
100   PrintHelp(lld::outs(), (std::string(argv0) + " [options] file...").c_str(),
101             "LLVM Linker", showHidden);
102   lld::outs() << "\n";
103 }
104 
105 static std::string rewritePath(StringRef s) {
106   if (fs::exists(s))
107     return relativeToRoot(s);
108   return std::string(s);
109 }
110 
111 // Reconstructs command line arguments so that so that you can re-run
112 // the same command with the same inputs. This is for --reproduce.
113 std::string macho::createResponseFile(const opt::InputArgList &args) {
114   SmallString<0> data;
115   raw_svector_ostream os(data);
116 
117   // Copy the command line to the output while rewriting paths.
118   for (auto *arg : args) {
119     switch (arg->getOption().getID()) {
120     case OPT_reproduce:
121       break;
122     case OPT_INPUT:
123       os << quote(rewritePath(arg->getValue())) << "\n";
124       break;
125     case OPT_o:
126       os << "-o " << quote(path::filename(arg->getValue())) << "\n";
127       break;
128     case OPT_filelist:
129       if (Optional<MemoryBufferRef> buffer = readFile(arg->getValue()))
130         for (StringRef path : args::getLines(*buffer))
131           os << quote(rewritePath(path)) << "\n";
132       break;
133     case OPT_force_load:
134     case OPT_rpath:
135     case OPT_syslibroot:
136     case OPT_F:
137     case OPT_L:
138     case OPT_order_file:
139       os << arg->getSpelling() << " " << quote(rewritePath(arg->getValue()))
140          << "\n";
141       break;
142     case OPT_sectcreate:
143       os << arg->getSpelling() << " " << quote(arg->getValue(0)) << " "
144          << quote(arg->getValue(1)) << " "
145          << quote(rewritePath(arg->getValue(2))) << "\n";
146       break;
147     default:
148       os << toString(*arg) << "\n";
149     }
150   }
151   return std::string(data.str());
152 }
153 
154 Optional<std::string> macho::resolveDylibPath(StringRef path) {
155   // TODO: if a tbd and dylib are both present, we should check to make sure
156   // they are consistent.
157   if (fs::exists(path))
158     return std::string(path);
159 
160   SmallString<261> location = path;
161   path::replace_extension(location, ".tbd");
162   if (fs::exists(location))
163     return std::string(location);
164 
165   return {};
166 }
167 
168 Optional<DylibFile *> macho::makeDylibFromTAPI(MemoryBufferRef mbref,
169                                                DylibFile *umbrella) {
170   Expected<std::unique_ptr<InterfaceFile>> result = TextAPIReader::get(mbref);
171   if (!result) {
172     error("could not load TAPI file at " + mbref.getBufferIdentifier() + ": " +
173           toString(result.takeError()));
174     return {};
175   }
176   return make<DylibFile>(**result, umbrella);
177 }
178