xref: /freebsd/contrib/llvm-project/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp (revision ec0ea6efa1ad229d75c394c1a9b9cac33af2b1d3)
1 //===- DlltoolDriver.cpp - dlltool.exe-compatible driver ------------------===//
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 // Defines an interface to a dlltool.exe-compatible driver.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ToolDrivers/llvm-dlltool/DlltoolDriver.h"
14 #include "llvm/ADT/Optional.h"
15 #include "llvm/Object/COFF.h"
16 #include "llvm/Object/COFFImportFile.h"
17 #include "llvm/Object/COFFModuleDefinition.h"
18 #include "llvm/Option/Arg.h"
19 #include "llvm/Option/ArgList.h"
20 #include "llvm/Option/Option.h"
21 #include "llvm/Support/Host.h"
22 #include "llvm/Support/Path.h"
23 
24 #include <vector>
25 
26 using namespace llvm;
27 using namespace llvm::object;
28 using namespace llvm::COFF;
29 
30 namespace {
31 
32 enum {
33   OPT_INVALID = 0,
34 #define OPTION(_1, _2, ID, _4, _5, _6, _7, _8, _9, _10, _11, _12) OPT_##ID,
35 #include "Options.inc"
36 #undef OPTION
37 };
38 
39 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
40 #include "Options.inc"
41 #undef PREFIX
42 
43 static const llvm::opt::OptTable::Info InfoTable[] = {
44 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12)      \
45   {X1, X2, X10,         X11,         OPT_##ID, llvm::opt::Option::KIND##Class, \
46    X9, X8, OPT_##GROUP, OPT_##ALIAS, X7,       X12},
47 #include "Options.inc"
48 #undef OPTION
49 };
50 
51 class DllOptTable : public llvm::opt::OptTable {
52 public:
53   DllOptTable() : OptTable(InfoTable, false) {}
54 };
55 
56 // Opens a file. Path has to be resolved already.
57 std::unique_ptr<MemoryBuffer> openFile(const Twine &Path) {
58   ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MB = MemoryBuffer::getFile(Path);
59 
60   if (std::error_code EC = MB.getError()) {
61     llvm::errs() << "cannot open file " << Path << ": " << EC.message() << "\n";
62     return nullptr;
63   }
64 
65   return std::move(*MB);
66 }
67 
68 MachineTypes getEmulation(StringRef S) {
69   return StringSwitch<MachineTypes>(S)
70       .Case("i386", IMAGE_FILE_MACHINE_I386)
71       .Case("i386:x86-64", IMAGE_FILE_MACHINE_AMD64)
72       .Case("arm", IMAGE_FILE_MACHINE_ARMNT)
73       .Case("arm64", IMAGE_FILE_MACHINE_ARM64)
74       .Default(IMAGE_FILE_MACHINE_UNKNOWN);
75 }
76 
77 MachineTypes getMachine(Triple T) {
78   switch (T.getArch()) {
79   case Triple::x86:
80     return COFF::IMAGE_FILE_MACHINE_I386;
81   case Triple::x86_64:
82     return COFF::IMAGE_FILE_MACHINE_AMD64;
83   case Triple::arm:
84     return COFF::IMAGE_FILE_MACHINE_ARMNT;
85   case Triple::aarch64:
86     return COFF::IMAGE_FILE_MACHINE_ARM64;
87   default:
88     return COFF::IMAGE_FILE_MACHINE_UNKNOWN;
89   }
90 }
91 
92 MachineTypes getDefaultMachine() {
93   return getMachine(Triple(sys::getDefaultTargetTriple()));
94 }
95 
96 Optional<std::string> getPrefix(StringRef Argv0) {
97   StringRef ProgName = llvm::sys::path::stem(Argv0);
98   // x86_64-w64-mingw32-dlltool -> x86_64-w64-mingw32
99   // llvm-dlltool -> None
100   // aarch64-w64-mingw32-llvm-dlltool-10.exe -> aarch64-w64-mingw32
101   ProgName = ProgName.rtrim("0123456789.-");
102   if (!ProgName.consume_back_insensitive("dlltool"))
103     return None;
104   ProgName.consume_back_insensitive("llvm-");
105   ProgName.consume_back_insensitive("-");
106   return ProgName.str();
107 }
108 
109 } // namespace
110 
111 int llvm::dlltoolDriverMain(llvm::ArrayRef<const char *> ArgsArr) {
112   DllOptTable Table;
113   unsigned MissingIndex;
114   unsigned MissingCount;
115   llvm::opt::InputArgList Args =
116       Table.ParseArgs(ArgsArr.slice(1), MissingIndex, MissingCount);
117   if (MissingCount) {
118     llvm::errs() << Args.getArgString(MissingIndex) << ": missing argument\n";
119     return 1;
120   }
121 
122   // Handle when no input or output is specified
123   if (Args.hasArgNoClaim(OPT_INPUT) ||
124       (!Args.hasArgNoClaim(OPT_d) && !Args.hasArgNoClaim(OPT_l))) {
125     Table.printHelp(outs(), "llvm-dlltool [options] file...", "llvm-dlltool",
126                     false);
127     llvm::outs() << "\nTARGETS: i386, i386:x86-64, arm, arm64\n";
128     return 1;
129   }
130 
131   for (auto *Arg : Args.filtered(OPT_UNKNOWN))
132     llvm::errs() << "ignoring unknown argument: " << Arg->getAsString(Args)
133                  << "\n";
134 
135   if (!Args.hasArg(OPT_d)) {
136     llvm::errs() << "no definition file specified\n";
137     return 1;
138   }
139 
140   std::unique_ptr<MemoryBuffer> MB =
141       openFile(Args.getLastArg(OPT_d)->getValue());
142   if (!MB)
143     return 1;
144 
145   if (!MB->getBufferSize()) {
146     llvm::errs() << "definition file empty\n";
147     return 1;
148   }
149 
150   COFF::MachineTypes Machine = getDefaultMachine();
151   if (Optional<std::string> Prefix = getPrefix(ArgsArr[0])) {
152     Triple T(*Prefix);
153     if (T.getArch() != Triple::UnknownArch)
154       Machine = getMachine(T);
155   }
156   if (auto *Arg = Args.getLastArg(OPT_m))
157     Machine = getEmulation(Arg->getValue());
158 
159   if (Machine == IMAGE_FILE_MACHINE_UNKNOWN) {
160     llvm::errs() << "unknown target\n";
161     return 1;
162   }
163 
164   Expected<COFFModuleDefinition> Def =
165       parseCOFFModuleDefinition(*MB, Machine, true);
166 
167   if (!Def) {
168     llvm::errs() << "error parsing definition\n"
169                  << errorToErrorCode(Def.takeError()).message();
170     return 1;
171   }
172 
173   // Do this after the parser because parseCOFFModuleDefinition sets OutputFile.
174   if (auto *Arg = Args.getLastArg(OPT_D))
175     Def->OutputFile = Arg->getValue();
176 
177   if (Def->OutputFile.empty()) {
178     llvm::errs() << "no DLL name specified\n";
179     return 1;
180   }
181 
182   std::string Path = std::string(Args.getLastArgValue(OPT_l));
183 
184   // If ExtName is set (if the "ExtName = Name" syntax was used), overwrite
185   // Name with ExtName and clear ExtName. When only creating an import
186   // library and not linking, the internal name is irrelevant. This avoids
187   // cases where writeImportLibrary tries to transplant decoration from
188   // symbol decoration onto ExtName.
189   for (COFFShortExport& E : Def->Exports) {
190     if (!E.ExtName.empty()) {
191       E.Name = E.ExtName;
192       E.ExtName.clear();
193     }
194   }
195 
196   if (Machine == IMAGE_FILE_MACHINE_I386 && Args.getLastArg(OPT_k)) {
197     for (COFFShortExport& E : Def->Exports) {
198       if (!E.AliasTarget.empty() || (!E.Name.empty() && E.Name[0] == '?'))
199         continue;
200       E.SymbolName = E.Name;
201       // Trim off the trailing decoration. Symbols will always have a
202       // starting prefix here (either _ for cdecl/stdcall, @ for fastcall
203       // or ? for C++ functions). Vectorcall functions won't have any
204       // fixed prefix, but the function base name will still be at least
205       // one char.
206       E.Name = E.Name.substr(0, E.Name.find('@', 1));
207       // By making sure E.SymbolName != E.Name for decorated symbols,
208       // writeImportLibrary writes these symbols with the type
209       // IMPORT_NAME_UNDECORATE.
210     }
211   }
212 
213   if (!Path.empty() &&
214       writeImportLibrary(Def->OutputFile, Path, Def->Exports, Machine, true))
215     return 1;
216   return 0;
217 }
218