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"
24
/// MemoryBuffer - This interface provides simple read-only access to a block
25
/// of memory, and provides simple methods for reading files and standard input
26
/// into a memory buffer. In addition to basic access to the characters in the
27
/// file, this interface guarantees you can read one character past the end of
28
/// the file, and that this character will read as '\0'.
30
/// The '\0' guarantee is needed to support an optimization -- it's intended to
31
/// be more efficient for clients which are reading all the data to stop
32
/// reading when they encounter a '\0' than to continually check the file
33
/// position to see if it has reached the end of the file.
35
const char *BufferStart; // Start of the buffer.
36
const char *BufferEnd; // End of the buffer.
38
MemoryBuffer(const MemoryBuffer &); // DO NOT IMPLEMENT
39
MemoryBuffer &operator=(const MemoryBuffer &); // DO NOT IMPLEMENT
42
void init(const char *BufStart, const char *BufEnd);
44
virtual ~MemoryBuffer();
46
const char *getBufferStart() const { return BufferStart; }
47
const char *getBufferEnd() const { return BufferEnd; }
48
size_t getBufferSize() const { return BufferEnd-BufferStart; }
50
StringRef getBuffer() const {
51
return StringRef(BufferStart, getBufferSize());
54
/// getBufferIdentifier - Return an identifier for this buffer, typically the
55
/// filename it was read from.
56
virtual const char *getBufferIdentifier() const {
57
return "Unknown buffer";
60
/// getFile - Open the specified file as a MemoryBuffer, returning a new
61
/// MemoryBuffer if successful, otherwise returning null. If FileSize is
62
/// specified, this means that the client knows that the file exists and that
63
/// it has the specified size.
64
static MemoryBuffer *getFile(StringRef Filename,
65
std::string *ErrStr = 0,
66
int64_t FileSize = -1,
67
struct stat *FileInfo = 0);
68
static MemoryBuffer *getFile(const char *Filename,
69
std::string *ErrStr = 0,
70
int64_t FileSize = -1,
71
struct stat *FileInfo = 0);
73
/// getMemBuffer - Open the specified memory range as a MemoryBuffer. Note
74
/// that EndPtr[0] must be a null byte and be accessible!
75
static MemoryBuffer *getMemBuffer(StringRef InputData,
76
StringRef BufferName = "");
78
/// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
79
/// copying the contents and taking ownership of it. This has no requirements
81
static MemoryBuffer *getMemBufferCopy(StringRef InputData,
82
StringRef BufferName = "");
84
/// getNewMemBuffer - Allocate a new MemoryBuffer of the specified size that
85
/// is completely initialized to zeros. Note that the caller should
86
/// initialize the memory allocated by this method. The memory is owned by
87
/// the MemoryBuffer object.
88
static MemoryBuffer *getNewMemBuffer(size_t Size, StringRef BufferName = "");
90
/// getNewUninitMemBuffer - Allocate a new MemoryBuffer of the specified size
91
/// that is not initialized. Note that the caller should initialize the
92
/// memory allocated by this method. The memory is owned by the MemoryBuffer
94
static MemoryBuffer *getNewUninitMemBuffer(size_t Size,
95
StringRef BufferName = "");
97
/// getSTDIN - Read all of stdin into a file buffer, and return it.
98
/// If an error occurs, this returns null and fills in *ErrStr with a reason.
99
static MemoryBuffer *getSTDIN(std::string *ErrStr = 0);
102
/// getFileOrSTDIN - Open the specified file as a MemoryBuffer, or open stdin
103
/// if the Filename is "-". If an error occurs, this returns null and fills
104
/// in *ErrStr with a reason.
105
static MemoryBuffer *getFileOrSTDIN(StringRef Filename,
106
std::string *ErrStr = 0,
107
int64_t FileSize = -1,
108
struct stat *FileInfo = 0);
109
static MemoryBuffer *getFileOrSTDIN(const char *Filename,
110
std::string *ErrStr = 0,
111
int64_t FileSize = -1,
112
struct stat *FileInfo = 0);
115
} // end namespace llvm