1 //===-- Path.cpp - Implement OS Path Concept --------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This header file implements the operating system Path concept.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/Support/Path.h"
15 #include "llvm/Config/config.h"
16 #include "llvm/Support/Endian.h"
17 #include "llvm/Support/FileSystem.h"
18 #include <cassert>
19 #include <cstring>
20 #include <ostream>
21 using namespace llvm;
22 using namespace sys;
23 namespace {
24 using support::ulittle32_t;
25 }
26
27 //===----------------------------------------------------------------------===//
28 //=== WARNING: Implementation here must contain only TRULY operating system
29 //=== independent code.
30 //===----------------------------------------------------------------------===//
31
operator ==(const Path & that) const32 bool Path::operator==(const Path &that) const {
33 return path == that.path;
34 }
35
operator <(const Path & that) const36 bool Path::operator<(const Path& that) const {
37 return path < that.path;
38 }
39
40 LLVMFileType
IdentifyFileType(const char * magic,unsigned length)41 sys::IdentifyFileType(const char *magic, unsigned length) {
42 assert(magic && "Invalid magic number string");
43 assert(length >=4 && "Invalid magic number length");
44 switch ((unsigned char)magic[0]) {
45 case 0xDE: // 0x0B17C0DE = BC wraper
46 if (magic[1] == (char)0xC0 && magic[2] == (char)0x17 &&
47 magic[3] == (char)0x0B)
48 return Bitcode_FileType;
49 break;
50 case 'B':
51 if (magic[1] == 'C' && magic[2] == (char)0xC0 && magic[3] == (char)0xDE)
52 return Bitcode_FileType;
53 break;
54 case '!':
55 if (length >= 8)
56 if (memcmp(magic,"!<arch>\n",8) == 0)
57 return Archive_FileType;
58 break;
59
60 case '\177':
61 if (magic[1] == 'E' && magic[2] == 'L' && magic[3] == 'F') {
62 bool Data2MSB = magic[5] == 2;
63 unsigned high = Data2MSB ? 16 : 17;
64 unsigned low = Data2MSB ? 17 : 16;
65 if (length >= 18 && magic[high] == 0)
66 switch (magic[low]) {
67 default: break;
68 case 1: return ELF_Relocatable_FileType;
69 case 2: return ELF_Executable_FileType;
70 case 3: return ELF_SharedObject_FileType;
71 case 4: return ELF_Core_FileType;
72 }
73 }
74 break;
75
76 case 0xCA:
77 if (magic[1] == char(0xFE) && magic[2] == char(0xBA) &&
78 magic[3] == char(0xBE)) {
79 // This is complicated by an overlap with Java class files.
80 // See the Mach-O section in /usr/share/file/magic for details.
81 if (length >= 8 && magic[7] < 43)
82 // FIXME: Universal Binary of any type.
83 return Mach_O_DynamicallyLinkedSharedLib_FileType;
84 }
85 break;
86
87 // The two magic numbers for mach-o are:
88 // 0xfeedface - 32-bit mach-o
89 // 0xfeedfacf - 64-bit mach-o
90 case 0xFE:
91 case 0xCE:
92 case 0xCF: {
93 uint16_t type = 0;
94 if (magic[0] == char(0xFE) && magic[1] == char(0xED) &&
95 magic[2] == char(0xFA) &&
96 (magic[3] == char(0xCE) || magic[3] == char(0xCF))) {
97 /* Native endian */
98 if (length >= 16) type = magic[14] << 8 | magic[15];
99 } else if ((magic[0] == char(0xCE) || magic[0] == char(0xCF)) &&
100 magic[1] == char(0xFA) && magic[2] == char(0xED) &&
101 magic[3] == char(0xFE)) {
102 /* Reverse endian */
103 if (length >= 14) type = magic[13] << 8 | magic[12];
104 }
105 switch (type) {
106 default: break;
107 case 1: return Mach_O_Object_FileType;
108 case 2: return Mach_O_Executable_FileType;
109 case 3: return Mach_O_FixedVirtualMemorySharedLib_FileType;
110 case 4: return Mach_O_Core_FileType;
111 case 5: return Mach_O_PreloadExecutable_FileType;
112 case 6: return Mach_O_DynamicallyLinkedSharedLib_FileType;
113 case 7: return Mach_O_DynamicLinker_FileType;
114 case 8: return Mach_O_Bundle_FileType;
115 case 9: return Mach_O_DynamicallyLinkedSharedLibStub_FileType;
116 case 10: return Mach_O_DSYMCompanion_FileType;
117 }
118 break;
119 }
120 case 0xF0: // PowerPC Windows
121 case 0x83: // Alpha 32-bit
122 case 0x84: // Alpha 64-bit
123 case 0x66: // MPS R4000 Windows
124 case 0x50: // mc68K
125 case 0x4c: // 80386 Windows
126 if (magic[1] == 0x01)
127 return COFF_FileType;
128
129 case 0x90: // PA-RISC Windows
130 case 0x68: // mc68K Windows
131 if (magic[1] == 0x02)
132 return COFF_FileType;
133 break;
134
135 case 0x4d: // Possible MS-DOS stub on Windows PE file
136 if (magic[1] == 0x5a) {
137 uint32_t off = *reinterpret_cast<const ulittle32_t *>(magic + 0x3c);
138 // PE/COFF file, either EXE or DLL.
139 if (off < length && memcmp(magic + off, "PE\0\0",4) == 0)
140 return COFF_FileType;
141 }
142 break;
143
144 case 0x64: // x86-64 Windows.
145 if (magic[1] == char(0x86))
146 return COFF_FileType;
147 break;
148
149 default:
150 break;
151 }
152 return Unknown_FileType;
153 }
154
155 bool
isArchive() const156 Path::isArchive() const {
157 fs::file_magic type;
158 if (fs::identify_magic(str(), type))
159 return false;
160 return type == fs::file_magic::archive;
161 }
162
163 bool
isDynamicLibrary() const164 Path::isDynamicLibrary() const {
165 fs::file_magic type;
166 if (fs::identify_magic(str(), type))
167 return false;
168 switch (type) {
169 default: return false;
170 case fs::file_magic::macho_fixed_virtual_memory_shared_lib:
171 case fs::file_magic::macho_dynamically_linked_shared_lib:
172 case fs::file_magic::macho_dynamically_linked_shared_lib_stub:
173 case fs::file_magic::elf_shared_object:
174 case fs::file_magic::pecoff_executable: return true;
175 }
176 }
177
178 bool
isObjectFile() const179 Path::isObjectFile() const {
180 fs::file_magic type;
181 if (fs::identify_magic(str(), type) || type == fs::file_magic::unknown)
182 return false;
183 return true;
184 }
185
186 Path
FindLibrary(std::string & name)187 Path::FindLibrary(std::string& name) {
188 std::vector<sys::Path> LibPaths;
189 GetSystemLibraryPaths(LibPaths);
190 for (unsigned i = 0; i < LibPaths.size(); ++i) {
191 sys::Path FullPath(LibPaths[i]);
192 FullPath.appendComponent("lib" + name + LTDL_SHLIB_EXT);
193 if (FullPath.isDynamicLibrary())
194 return FullPath;
195 FullPath.eraseSuffix();
196 FullPath.appendSuffix("a");
197 if (FullPath.isArchive())
198 return FullPath;
199 }
200 return sys::Path();
201 }
202
GetDLLSuffix()203 StringRef Path::GetDLLSuffix() {
204 return &(LTDL_SHLIB_EXT[1]);
205 }
206
207 void
appendSuffix(StringRef suffix)208 Path::appendSuffix(StringRef suffix) {
209 if (!suffix.empty()) {
210 path.append(".");
211 path.append(suffix);
212 }
213 }
214
215 bool
isBitcodeFile() const216 Path::isBitcodeFile() const {
217 fs::file_magic type;
218 if (fs::identify_magic(str(), type))
219 return false;
220 return type == fs::file_magic::bitcode;
221 }
222
hasMagicNumber(StringRef Magic) const223 bool Path::hasMagicNumber(StringRef Magic) const {
224 std::string actualMagic;
225 if (getMagicNumber(actualMagic, static_cast<unsigned>(Magic.size())))
226 return Magic == actualMagic;
227 return false;
228 }
229
getPathList(const char * path,std::vector<Path> & Paths)230 static void getPathList(const char*path, std::vector<Path>& Paths) {
231 const char* at = path;
232 const char* delim = strchr(at, PathSeparator);
233 Path tmpPath;
234 while (delim != 0) {
235 std::string tmp(at, size_t(delim-at));
236 if (tmpPath.set(tmp))
237 if (tmpPath.canRead())
238 Paths.push_back(tmpPath);
239 at = delim + 1;
240 delim = strchr(at, PathSeparator);
241 }
242
243 if (*at != 0)
244 if (tmpPath.set(std::string(at)))
245 if (tmpPath.canRead())
246 Paths.push_back(tmpPath);
247 }
248
getDirnameCharSep(StringRef path,const char * Sep)249 static StringRef getDirnameCharSep(StringRef path, const char *Sep) {
250 assert(Sep[0] != '\0' && Sep[1] == '\0' &&
251 "Sep must be a 1-character string literal.");
252 if (path.empty())
253 return ".";
254
255 // If the path is all slashes, return a single slash.
256 // Otherwise, remove all trailing slashes.
257
258 signed pos = static_cast<signed>(path.size()) - 1;
259
260 while (pos >= 0 && path[pos] == Sep[0])
261 --pos;
262
263 if (pos < 0)
264 return path[0] == Sep[0] ? Sep : ".";
265
266 // Any slashes left?
267 signed i = 0;
268
269 while (i < pos && path[i] != Sep[0])
270 ++i;
271
272 if (i == pos) // No slashes? Return "."
273 return ".";
274
275 // There is at least one slash left. Remove all trailing non-slashes.
276 while (pos >= 0 && path[pos] != Sep[0])
277 --pos;
278
279 // Remove any trailing slashes.
280 while (pos >= 0 && path[pos] == Sep[0])
281 --pos;
282
283 if (pos < 0)
284 return path[0] == Sep[0] ? Sep : ".";
285
286 return path.substr(0, pos+1);
287 }
288
289 // Include the truly platform-specific parts of this class.
290 #if defined(LLVM_ON_UNIX)
291 #include "Unix/Path.inc"
292 #endif
293 #if defined(LLVM_ON_WIN32)
294 #include "Windows/Path.inc"
295 #endif
296