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[oota-llvm.git] / lib / System / Path.cpp

diff --git a/lib/System/Path.cpp b/lib/System/Path.cpp
index 34cbd6d69b7fef691d1ee20de0e176d7fcaf667c..11035cfee7aa55d6ba55973905eeebd730a44934 100644 (file)
--- a/lib/System/Path.cpp
+++ b/lib/System/Path.cpp
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Reid Spencer and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -14,8 +14,9 @@
 #include "llvm/System/Path.h"
 #include "llvm/Config/config.h"
 #include <cassert>
-
-namespace llvm {
+#include <cstring>
+#include <ostream>
+using namespace llvm;
 using namespace sys;
 
 //===----------------------------------------------------------------------===//
@@ -23,11 +24,16 @@ using namespace sys;
 //===          independent code.
 //===----------------------------------------------------------------------===//
 
+std::ostream& llvm::operator<<(std::ostream &strm, const sys::Path &aPath) {
+  strm << aPath.toString();
+  return strm;
+}
+
 Path
 Path::GetLLVMConfigDir() {
   Path result;
 #ifdef LLVM_ETCDIR
-  if (result.setDirectory(LLVM_ETCDIR))
+  if (result.set(LLVM_ETCDIR))
     return result;
 #endif
   return GetLLVMDefaultConfigDir();
@@ -38,39 +44,95 @@ sys::IdentifyFileType(const char*magic, unsigned length) {
   assert(magic && "Invalid magic number string");
   assert(length >=4 && "Invalid magic number length");
   switch (magic[0]) {
-    case 'l':
-      if (magic[1] == 'l' && magic[2] == 'v') {
-        if (magic[3] == 'c')
-          return CompressedBytecodeFileType;
-        else if (magic[3] == 'm')
-          return BytecodeFileType;
-      }
+    case 'B':
+      if (magic[1] == 'C' && magic[2] == (char)0xC0 && magic[3] == (char)0xDE)
+        return Bitcode_FileType;
       break;
-
     case '!':
-      if (length >= 8) {
+      if (length >= 8)
         if (memcmp(magic,"!<arch>\n",8) == 0)
-          return ArchiveFileType;
+          return Archive_FileType;
+      break;
+      
+    case '\177':
+      if (magic[1] == 'E' && magic[2] == 'L' && magic[3] == 'F') {
+        if (length >= 18 && magic[17] == 0)
+          switch (magic[16]) {
+            default: break;
+            case 1: return ELF_Relocatable_FileType;
+            case 2: return ELF_Executable_FileType;
+            case 3: return ELF_SharedObject_FileType;
+            case 4: return ELF_Core_FileType;
+          }
       }
       break;
 
+    case 0xCA:
+      // This is complicated by an overlap with Java class files. 
+      // See the Mach-O section in /usr/share/file/magic for details.
+      if (magic[1] == char(0xFE) && magic[2] == char(0xBA) && 
+          magic[3] == char(0xBE)) {
+        return Mach_O_DynamicallyLinkedSharedLib_FileType;
+        
+        // FIXME: How does this work?
+        if (length >= 14 && magic[13] == 0)
+          switch (magic[12]) {
+            default: break;
+            case 1: return Mach_O_Object_FileType;
+            case 2: return Mach_O_Executable_FileType;
+            case 3: return Mach_O_FixedVirtualMemorySharedLib_FileType;
+            case 4: return Mach_O_Core_FileType;
+            case 5: return Mach_O_PreloadExectuable_FileType;
+            case 6: return Mach_O_DynamicallyLinkedSharedLib_FileType;
+            case 7: return Mach_O_DynamicLinker_FileType;
+            case 8: return Mach_O_Bundle_FileType;
+            case 9: return Mach_O_DynamicallyLinkedSharedLibStub_FileType;
+          }
+      }
+      break;
+
+    case 0xF0: // PowerPC Windows
+    case 0x83: // Alpha 32-bit
+    case 0x84: // Alpha 64-bit
+    case 0x66: // MPS R4000 Windows
+    case 0x50: // mc68K
+    case 0x4c: // 80386 Windows
+      if (magic[1] == 0x01)
+        return COFF_FileType;
+
+    case 0x90: // PA-RISC Windows
+    case 0x68: // mc68K Windows
+      if (magic[1] == 0x02)
+        return COFF_FileType;
+      break;
+
     default:
       break;
   }
-  return UnknownFileType;
+  return Unknown_FileType;
 }
 
 bool
 Path::isArchive() const {
-  if (readable())
+  if (canRead())
     return hasMagicNumber("!<arch>\012");
   return false;
 }
 
 bool
 Path::isDynamicLibrary() const {
-  if (readable())
-    return hasMagicNumber("\177ELF");
+  if (canRead()) {
+    std::string Magic;
+    if (getMagicNumber(Magic, 64))
+      switch (IdentifyFileType(Magic.c_str(), Magic.length())) {
+        default: return false;
+        case Mach_O_FixedVirtualMemorySharedLib_FileType:
+        case Mach_O_DynamicallyLinkedSharedLib_FileType:
+        case Mach_O_DynamicallyLinkedSharedLibStub_FileType:
+        case ELF_SharedObject_FileType:
+        case COFF_FileType:  return true;
+      }
+  }
   return false;
 }
 
@@ -80,10 +142,10 @@ Path::FindLibrary(std::string& name) {
   GetSystemLibraryPaths(LibPaths);
   for (unsigned i = 0; i < LibPaths.size(); ++i) {
     sys::Path FullPath(LibPaths[i]);
-    FullPath.appendFile("lib" + name + LTDL_SHLIB_EXT);
+    FullPath.appendComponent("lib" + name + LTDL_SHLIB_EXT);
     if (FullPath.isDynamicLibrary())
       return FullPath;
-    FullPath.elideSuffix();
+    FullPath.eraseSuffix();
     FullPath.appendSuffix("a");
     if (FullPath.isArchive())
       return FullPath;
@@ -91,15 +153,31 @@ Path::FindLibrary(std::string& name) {
   return sys::Path();
 }
 
-std::string
-Path::GetDLLSuffix() {
+std::string Path::GetDLLSuffix() {
   return LTDL_SHLIB_EXT;
 }
 
+bool
+Path::isBitcodeFile() const {
+  std::string actualMagic;
+  if (!getMagicNumber(actualMagic, 4))
+    return false;
+  return actualMagic == "BC\xC0\xDE";
 }
 
-// Include the truly platform-specific parts of this class.
+bool Path::hasMagicNumber(const std::string &Magic) const {
+  std::string actualMagic;
+  if (getMagicNumber(actualMagic, Magic.size()))
+    return Magic == actualMagic;
+  return false;
+}
 
+std::string
+Path::getSuffix() const {
+  return path.substr(path.rfind('.') + 1);
+}
+
+// Include the truly platform-specific parts of this class.
 #if defined(LLVM_ON_UNIX)
 #include "Unix/Path.inc"
 #endif