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/Support/FileSystem.h"
16 #include "llvm/Config/config.h"
17 #include "llvm/Support/FileSystem.h"
18 #include "llvm/Support/Endian.h"
19 #include <cassert>
20 #include <cstring>
21 #include <ostream>
22 using namespace llvm;
23 using namespace sys;
24 namespace {
25 using support::ulittle32_t;
26 }
27
28 //===----------------------------------------------------------------------===//
29 //=== WARNING: Implementation here must contain only TRULY operating system
30 //=== independent code.
31 //===----------------------------------------------------------------------===//
32
operator ==(const Path & that) const33 bool Path::operator==(const Path &that) const {
34 return path == that.path;
35 }
36
operator <(const Path & that) const37 bool Path::operator<(const Path& that) const {
38 return path < that.path;
39 }
40
41 LLVMFileType
IdentifyFileType(const char * magic,unsigned length)42 sys::IdentifyFileType(const char *magic, unsigned length) {
43 assert(magic && "Invalid magic number string");
44 assert(length >=4 && "Invalid magic number length");
45 switch ((unsigned char)magic[0]) {
46 case 0xDE: // 0x0B17C0DE = BC wraper
47 if (magic[1] == (char)0xC0 && magic[2] == (char)0x17 &&
48 magic[3] == (char)0x0B)
49 return Bitcode_FileType;
50 break;
51 case 'B':
52 if (magic[1] == 'C' && magic[2] == (char)0xC0 && magic[3] == (char)0xDE)
53 return Bitcode_FileType;
54 break;
55 case '!':
56 if (length >= 8)
57 if (memcmp(magic,"!<arch>\n",8) == 0)
58 return Archive_FileType;
59 break;
60
61 case '\177':
62 if (magic[1] == 'E' && magic[2] == 'L' && magic[3] == 'F') {
63 if (length >= 18 && magic[17] == 0)
64 switch (magic[16]) {
65 default: break;
66 case 1: return ELF_Relocatable_FileType;
67 case 2: return ELF_Executable_FileType;
68 case 3: return ELF_SharedObject_FileType;
69 case 4: return ELF_Core_FileType;
70 }
71 }
72 break;
73
74 case 0xCA:
75 if (magic[1] == char(0xFE) && magic[2] == char(0xBA) &&
76 magic[3] == char(0xBE)) {
77 // This is complicated by an overlap with Java class files.
78 // See the Mach-O section in /usr/share/file/magic for details.
79 if (length >= 8 && magic[7] < 43)
80 // FIXME: Universal Binary of any type.
81 return Mach_O_DynamicallyLinkedSharedLib_FileType;
82 }
83 break;
84
85 // The two magic numbers for mach-o are:
86 // 0xfeedface - 32-bit mach-o
87 // 0xfeedfacf - 64-bit mach-o
88 case 0xFE:
89 case 0xCE:
90 case 0xCF: {
91 uint16_t type = 0;
92 if (magic[0] == char(0xFE) && magic[1] == char(0xED) &&
93 magic[2] == char(0xFA) &&
94 (magic[3] == char(0xCE) || magic[3] == char(0xCF))) {
95 /* Native endian */
96 if (length >= 16) type = magic[14] << 8 | magic[15];
97 } else if ((magic[0] == char(0xCE) || magic[0] == char(0xCF)) &&
98 magic[1] == char(0xFA) && magic[2] == char(0xED) &&
99 magic[3] == char(0xFE)) {
100 /* Reverse endian */
101 if (length >= 14) type = magic[13] << 8 | magic[12];
102 }
103 switch (type) {
104 default: break;
105 case 1: return Mach_O_Object_FileType;
106 case 2: return Mach_O_Executable_FileType;
107 case 3: return Mach_O_FixedVirtualMemorySharedLib_FileType;
108 case 4: return Mach_O_Core_FileType;
109 case 5: return Mach_O_PreloadExecutable_FileType;
110 case 6: return Mach_O_DynamicallyLinkedSharedLib_FileType;
111 case 7: return Mach_O_DynamicLinker_FileType;
112 case 8: return Mach_O_Bundle_FileType;
113 case 9: return Mach_O_DynamicallyLinkedSharedLibStub_FileType;
114 case 10: return Mach_O_DSYMCompanion_FileType;
115 }
116 break;
117 }
118 case 0xF0: // PowerPC Windows
119 case 0x83: // Alpha 32-bit
120 case 0x84: // Alpha 64-bit
121 case 0x66: // MPS R4000 Windows
122 case 0x50: // mc68K
123 case 0x4c: // 80386 Windows
124 if (magic[1] == 0x01)
125 return COFF_FileType;
126
127 case 0x90: // PA-RISC Windows
128 case 0x68: // mc68K Windows
129 if (magic[1] == 0x02)
130 return COFF_FileType;
131 break;
132
133 case 0x4d: // Possible MS-DOS stub on Windows PE file
134 if (magic[1] == 0x5a) {
135 uint32_t off = *reinterpret_cast<const ulittle32_t *>(magic + 0x3c);
136 // PE/COFF file, either EXE or DLL.
137 if (off < length && memcmp(magic + off, "PE\0\0",4) == 0)
138 return COFF_FileType;
139 }
140 break;
141
142 case 0x64: // x86-64 Windows.
143 if (magic[1] == char(0x86))
144 return COFF_FileType;
145 break;
146
147 default:
148 break;
149 }
150 return Unknown_FileType;
151 }
152
153 bool
isArchive() const154 Path::isArchive() const {
155 fs::file_magic type;
156 if (fs::identify_magic(str(), type))
157 return false;
158 return type == fs::file_magic::archive;
159 }
160
161 bool
isDynamicLibrary() const162 Path::isDynamicLibrary() const {
163 fs::file_magic type;
164 if (fs::identify_magic(str(), type))
165 return false;
166 switch (type) {
167 default: return false;
168 case fs::file_magic::macho_fixed_virtual_memory_shared_lib:
169 case fs::file_magic::macho_dynamically_linked_shared_lib:
170 case fs::file_magic::macho_dynamically_linked_shared_lib_stub:
171 case fs::file_magic::elf_shared_object:
172 case fs::file_magic::pecoff_executable: return true;
173 }
174 }
175
176 bool
isObjectFile() const177 Path::isObjectFile() const {
178 fs::file_magic type;
179 if (fs::identify_magic(str(), type) || type == fs::file_magic::unknown)
180 return false;
181 return true;
182 }
183
184 Path
FindLibrary(std::string & name)185 Path::FindLibrary(std::string& name) {
186 std::vector<sys::Path> LibPaths;
187 GetSystemLibraryPaths(LibPaths);
188 for (unsigned i = 0; i < LibPaths.size(); ++i) {
189 sys::Path FullPath(LibPaths[i]);
190 FullPath.appendComponent("lib" + name + LTDL_SHLIB_EXT);
191 if (FullPath.isDynamicLibrary())
192 return FullPath;
193 FullPath.eraseSuffix();
194 FullPath.appendSuffix("a");
195 if (FullPath.isArchive())
196 return FullPath;
197 }
198 return sys::Path();
199 }
200
GetDLLSuffix()201 StringRef Path::GetDLLSuffix() {
202 return &(LTDL_SHLIB_EXT[1]);
203 }
204
205 void
appendSuffix(StringRef suffix)206 Path::appendSuffix(StringRef suffix) {
207 if (!suffix.empty()) {
208 path.append(".");
209 path.append(suffix);
210 }
211 }
212
213 bool
isBitcodeFile() const214 Path::isBitcodeFile() const {
215 fs::file_magic type;
216 if (fs::identify_magic(str(), type))
217 return false;
218 return type == fs::file_magic::bitcode;
219 }
220
hasMagicNumber(StringRef Magic) const221 bool Path::hasMagicNumber(StringRef Magic) const {
222 std::string actualMagic;
223 if (getMagicNumber(actualMagic, static_cast<unsigned>(Magic.size())))
224 return Magic == actualMagic;
225 return false;
226 }
227
getPathList(const char * path,std::vector<Path> & Paths)228 static void getPathList(const char*path, std::vector<Path>& Paths) {
229 const char* at = path;
230 const char* delim = strchr(at, PathSeparator);
231 Path tmpPath;
232 while (delim != 0) {
233 std::string tmp(at, size_t(delim-at));
234 if (tmpPath.set(tmp))
235 if (tmpPath.canRead())
236 Paths.push_back(tmpPath);
237 at = delim + 1;
238 delim = strchr(at, PathSeparator);
239 }
240
241 if (*at != 0)
242 if (tmpPath.set(std::string(at)))
243 if (tmpPath.canRead())
244 Paths.push_back(tmpPath);
245 }
246
getDirnameCharSep(StringRef path,const char * Sep)247 static StringRef getDirnameCharSep(StringRef path, const char *Sep) {
248 assert(Sep[0] != '\0' && Sep[1] == '\0' &&
249 "Sep must be a 1-character string literal.");
250 if (path.empty())
251 return ".";
252
253 // If the path is all slashes, return a single slash.
254 // Otherwise, remove all trailing slashes.
255
256 signed pos = static_cast<signed>(path.size()) - 1;
257
258 while (pos >= 0 && path[pos] == Sep[0])
259 --pos;
260
261 if (pos < 0)
262 return path[0] == Sep[0] ? Sep : ".";
263
264 // Any slashes left?
265 signed i = 0;
266
267 while (i < pos && path[i] != Sep[0])
268 ++i;
269
270 if (i == pos) // No slashes? Return "."
271 return ".";
272
273 // There is at least one slash left. Remove all trailing non-slashes.
274 while (pos >= 0 && path[pos] != Sep[0])
275 --pos;
276
277 // Remove any trailing slashes.
278 while (pos >= 0 && path[pos] == Sep[0])
279 --pos;
280
281 if (pos < 0)
282 return path[0] == Sep[0] ? Sep : ".";
283
284 return path.substr(0, pos+1);
285 }
286
287 // Include the truly platform-specific parts of this class.
288 #if defined(LLVM_ON_UNIX)
289 #include "Unix/Path.inc"
290 #endif
291 #if defined(LLVM_ON_WIN32)
292 #include "Windows/Path.inc"
293 #endif
294