1 //===--- MemoryBuffer.h - Memory Buffer Interface ---------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the MemoryBuffer interface.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_SUPPORT_MEMORYBUFFER_H
15 #define LLVM_SUPPORT_MEMORYBUFFER_H
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/System/DataTypes.h"
23 /// MemoryBuffer - This interface provides simple read-only access to a block
24 /// of memory, and provides simple methods for reading files and standard input
25 /// into a memory buffer. In addition to basic access to the characters in the
26 /// file, this interface guarantees you can read one character past the end of
27 /// the file, and that this character will read as '\0'.
29 const char *BufferStart; // Start of the buffer.
30 const char *BufferEnd; // End of the buffer.
32 /// MustDeleteBuffer - True if we allocated this buffer. If so, the
33 /// destructor must know the delete[] it.
34 bool MustDeleteBuffer;
36 MemoryBuffer() : MustDeleteBuffer(false) {}
37 void init(const char *BufStart, const char *BufEnd);
38 void initCopyOf(const char *BufStart, const char *BufEnd);
40 virtual ~MemoryBuffer();
42 const char *getBufferStart() const { return BufferStart; }
43 const char *getBufferEnd() const { return BufferEnd; }
44 size_t getBufferSize() const { return BufferEnd-BufferStart; }
46 StringRef getBuffer() const {
47 return StringRef(BufferStart, getBufferSize());
50 /// getBufferIdentifier - Return an identifier for this buffer, typically the
51 /// filename it was read from.
52 virtual const char *getBufferIdentifier() const {
53 return "Unknown buffer";
56 /// getFile - Open the specified file as a MemoryBuffer, returning a new
57 /// MemoryBuffer if successful, otherwise returning null. If FileSize is
58 /// specified, this means that the client knows that the file exists and that
59 /// it has the specified size.
60 static MemoryBuffer *getFile(StringRef Filename,
61 std::string *ErrStr = 0,
62 int64_t FileSize = -1);
64 /// getMemBuffer - Open the specified memory range as a MemoryBuffer. Note
65 /// that EndPtr[0] must be a null byte and be accessible!
66 static MemoryBuffer *getMemBuffer(const char *StartPtr, const char *EndPtr,
67 const char *BufferName = "");
69 /// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
70 /// copying the contents and taking ownership of it. This has no requirements
72 static MemoryBuffer *getMemBufferCopy(const char *StartPtr,const char *EndPtr,
73 const char *BufferName = "");
75 /// getNewMemBuffer - Allocate a new MemoryBuffer of the specified size that
76 /// is completely initialized to zeros. Note that the caller should
77 /// initialize the memory allocated by this method. The memory is owned by
78 /// the MemoryBuffer object.
79 static MemoryBuffer *getNewMemBuffer(size_t Size,
80 const char *BufferName = "");
82 /// getNewUninitMemBuffer - Allocate a new MemoryBuffer of the specified size
83 /// that is not initialized. Note that the caller should initialize the
84 /// memory allocated by this method. The memory is owned by the MemoryBuffer
86 static MemoryBuffer *getNewUninitMemBuffer(size_t Size,
87 StringRef BufferName = "");
89 /// getSTDIN - Read all of stdin into a file buffer, and return it.
90 static MemoryBuffer *getSTDIN();
93 /// getFileOrSTDIN - Open the specified file as a MemoryBuffer, or open stdin
94 /// if the Filename is "-". If an error occurs, this returns null and fills
95 /// in *ErrStr with a reason.
96 static MemoryBuffer *getFileOrSTDIN(StringRef Filename,
97 std::string *ErrStr = 0,
98 int64_t FileSize = -1);
101 } // end namespace llvm