X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FSupport%2FMemoryBuffer.h;h=06816de9716ae6a34e0e70a8d1b9304aee7ca8a4;hb=cbeb8d9869aafec3c2c1ee0922f0a4d5bb4a916a;hp=95d0d3d6e8234c89fe79d77d6fac714a75addd70;hpb=d65267ee625bb9cf8dc655a0c0409760e2b76c71;p=oota-llvm.git diff --git a/include/llvm/Support/MemoryBuffer.h b/include/llvm/Support/MemoryBuffer.h index 95d0d3d6e82..06816de9716 100644 --- a/include/llvm/Support/MemoryBuffer.h +++ b/include/llvm/Support/MemoryBuffer.h @@ -15,27 +15,33 @@ #define LLVM_SUPPORT_MEMORYBUFFER_H #include "llvm/ADT/StringRef.h" -#include "llvm/System/DataTypes.h" -#include +#include "llvm/Support/DataTypes.h" namespace llvm { +class error_code; +template class OwningPtr; + /// MemoryBuffer - This interface provides simple read-only access to a block /// of memory, and provides simple methods for reading files and standard input /// into a memory buffer. In addition to basic access to the characters in the /// file, this interface guarantees you can read one character past the end of -/// @verbatim the file, and that this character will read as '\0'. @endverbatim +/// the file, and that this character will read as '\0'. +/// +/// The '\0' guarantee is needed to support an optimization -- it's intended to +/// be more efficient for clients which are reading all the data to stop +/// reading when they encounter a '\0' than to continually check the file +/// position to see if it has reached the end of the file. class MemoryBuffer { const char *BufferStart; // Start of the buffer. const char *BufferEnd; // End of the buffer. - /// MustDeleteBuffer - True if we allocated this buffer. If so, the - /// destructor must know the delete[] it. - bool MustDeleteBuffer; + MemoryBuffer(const MemoryBuffer &); // DO NOT IMPLEMENT + MemoryBuffer &operator=(const MemoryBuffer &); // DO NOT IMPLEMENT protected: - MemoryBuffer() : MustDeleteBuffer(false) {} - void init(const char *BufStart, const char *BufEnd); - void initCopyOf(const char *BufStart, const char *BufEnd); + MemoryBuffer() {} + void init(const char *BufStart, const char *BufEnd, + bool RequiresNullTerminator); public: virtual ~MemoryBuffer(); @@ -43,8 +49,8 @@ public: const char *getBufferEnd() const { return BufferEnd; } size_t getBufferSize() const { return BufferEnd-BufferStart; } - StringRef getBuffer() const { - return StringRef(BufferStart, getBufferSize()); + StringRef getBuffer() const { + return StringRef(BufferStart, getBufferSize()); } /// getBufferIdentifier - Return an identifier for this buffer, typically the @@ -57,27 +63,40 @@ public: /// MemoryBuffer if successful, otherwise returning null. If FileSize is /// specified, this means that the client knows that the file exists and that /// it has the specified size. - static MemoryBuffer *getFile(StringRef Filename, - std::string *ErrStr = 0, - int64_t FileSize = -1); + static error_code getFile(StringRef Filename, OwningPtr &result, + int64_t FileSize = -1, + bool RequiresNullTerminator = true); + static error_code getFile(const char *Filename, + OwningPtr &result, + int64_t FileSize = -1, + bool RequiresNullTerminator = true); + + /// getOpenFile - Given an already-open file descriptor, read the file and + /// return a MemoryBuffer. + static error_code getOpenFile(int FD, const char *Filename, + OwningPtr &result, + uint64_t FileSize = -1, + uint64_t MapSize = -1, + int64_t Offset = 0, + bool RequiresNullTerminator = true); /// getMemBuffer - Open the specified memory range as a MemoryBuffer. Note - /// that EndPtr[0] must be a null byte and be accessible! - static MemoryBuffer *getMemBuffer(const char *StartPtr, const char *EndPtr, - const char *BufferName = ""); + /// that InputData must be null terminated if RequiresNullTerminator is true. + static MemoryBuffer *getMemBuffer(StringRef InputData, + StringRef BufferName = "", + bool RequiresNullTerminator = true); /// getMemBufferCopy - Open the specified memory range as a MemoryBuffer, - /// copying the contents and taking ownership of it. This has no requirements - /// on EndPtr[0]. - static MemoryBuffer *getMemBufferCopy(const char *StartPtr,const char *EndPtr, - const char *BufferName = ""); + /// copying the contents and taking ownership of it. InputData does not + /// have to be null terminated. + static MemoryBuffer *getMemBufferCopy(StringRef InputData, + StringRef BufferName = ""); /// getNewMemBuffer - Allocate a new MemoryBuffer of the specified size that /// is completely initialized to zeros. Note that the caller should /// initialize the memory allocated by this method. The memory is owned by /// the MemoryBuffer object. - static MemoryBuffer *getNewMemBuffer(size_t Size, - const char *BufferName = ""); + static MemoryBuffer *getNewMemBuffer(size_t Size, StringRef BufferName = ""); /// getNewUninitMemBuffer - Allocate a new MemoryBuffer of the specified size /// that is not initialized. Note that the caller should initialize the @@ -87,15 +106,34 @@ public: StringRef BufferName = ""); /// getSTDIN - Read all of stdin into a file buffer, and return it. - static MemoryBuffer *getSTDIN(); + /// If an error occurs, this returns null and sets ec. + static error_code getSTDIN(OwningPtr &result); /// getFileOrSTDIN - Open the specified file as a MemoryBuffer, or open stdin - /// if the Filename is "-". If an error occurs, this returns null and fills - /// in *ErrStr with a reason. - static MemoryBuffer *getFileOrSTDIN(StringRef Filename, - std::string *ErrStr = 0, - int64_t FileSize = -1); + /// if the Filename is "-". If an error occurs, this returns null and sets + /// ec. + static error_code getFileOrSTDIN(StringRef Filename, + OwningPtr &result, + int64_t FileSize = -1); + static error_code getFileOrSTDIN(const char *Filename, + OwningPtr &result, + int64_t FileSize = -1); + + + //===--------------------------------------------------------------------===// + // Provided for performance analysis. + //===--------------------------------------------------------------------===// + + /// The kind of memory backing used to support the MemoryBuffer. + enum BufferKind { + MemoryBuffer_Malloc, + MemoryBuffer_MMap + }; + + /// Return information on the memory mechanism used to support the + /// MemoryBuffer. + virtual BufferKind getBufferKind() const = 0; }; } // end namespace llvm