| //===--- MemoryBuffer.h - Memory Buffer Interface ---------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the MemoryBuffer interface. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_SUPPORT_MEMORYBUFFER_H |
| #define LLVM_SUPPORT_MEMORYBUFFER_H |
| |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/Support/DataTypes.h" |
| |
| namespace llvm { |
| |
| class error_code; |
| template<class T> 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 |
| /// 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. |
| |
| MemoryBuffer(const MemoryBuffer &); // DO NOT IMPLEMENT |
| MemoryBuffer &operator=(const MemoryBuffer &); // DO NOT IMPLEMENT |
| protected: |
| MemoryBuffer() {} |
| void init(const char *BufStart, const char *BufEnd, |
| bool RequiresNullTerminator); |
| public: |
| virtual ~MemoryBuffer(); |
| |
| const char *getBufferStart() const { return BufferStart; } |
| const char *getBufferEnd() const { return BufferEnd; } |
| size_t getBufferSize() const { return BufferEnd-BufferStart; } |
| |
| StringRef getBuffer() const { |
| return StringRef(BufferStart, getBufferSize()); |
| } |
| |
| /// getBufferIdentifier - Return an identifier for this buffer, typically the |
| /// filename it was read from. |
| virtual const char *getBufferIdentifier() const { |
| return "Unknown buffer"; |
| } |
| |
| /// getFile - Open the specified file as a MemoryBuffer, returning a new |
| /// 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 error_code getFile(StringRef Filename, OwningPtr<MemoryBuffer> &result, |
| int64_t FileSize = -1, |
| bool RequiresNullTerminator = true); |
| static error_code getFile(const char *Filename, |
| OwningPtr<MemoryBuffer> &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<MemoryBuffer> &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 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. 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, StringRef BufferName = ""); |
| |
| /// getNewUninitMemBuffer - Allocate a new MemoryBuffer of the specified size |
| /// that is not initialized. Note that the caller should initialize the |
| /// memory allocated by this method. The memory is owned by the MemoryBuffer |
| /// object. |
| static MemoryBuffer *getNewUninitMemBuffer(size_t Size, |
| StringRef BufferName = ""); |
| |
| /// getSTDIN - Read all of stdin into a file buffer, and return it. |
| /// If an error occurs, this returns null and sets ec. |
| static error_code getSTDIN(OwningPtr<MemoryBuffer> &result); |
| |
| |
| /// getFileOrSTDIN - Open the specified file as a MemoryBuffer, or open stdin |
| /// if the Filename is "-". If an error occurs, this returns null and sets |
| /// ec. |
| static error_code getFileOrSTDIN(StringRef Filename, |
| OwningPtr<MemoryBuffer> &result, |
| int64_t FileSize = -1); |
| static error_code getFileOrSTDIN(const char *Filename, |
| OwningPtr<MemoryBuffer> &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 |
| |
| #endif |