//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Chris Lattner 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.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/System/MappedFile.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/System/Errno.h"
+#include "llvm/System/Path.h"
#include "llvm/System/Process.h"
+#include "llvm/System/Program.h"
#include <cassert>
#include <cstdio>
#include <cstring>
#include <cerrno>
+#include <sys/types.h>
+#include <sys/stat.h>
+#if !defined(_MSC_VER) && !defined(__MINGW32__)
+#include <unistd.h>
+#include <sys/uio.h>
+#else
+#include <io.h>
+#endif
+#include <fcntl.h>
using namespace llvm;
//===----------------------------------------------------------------------===//
// MemoryBuffer implementation itself.
//===----------------------------------------------------------------------===//
-MemoryBuffer::~MemoryBuffer() {
- if (MustDeleteBuffer)
- delete [] BufferStart;
-}
-
-/// initCopyOf - Initialize this source buffer with a copy of the specified
-/// memory range. We make the copy so that we can null terminate it
-/// successfully.
-void MemoryBuffer::initCopyOf(const char *BufStart, const char *BufEnd) {
- size_t Size = BufEnd-BufStart;
- BufferStart = new char[Size+1];
- BufferEnd = BufferStart+Size;
- memcpy(const_cast<char*>(BufferStart), BufStart, Size);
- *const_cast<char*>(BufferEnd) = 0; // Null terminate buffer.
- MustDeleteBuffer = false;
-}
+MemoryBuffer::~MemoryBuffer() { }
/// init - Initialize this MemoryBuffer as a reference to externally allocated
/// memory, memory that we know is already null terminated.
assert(BufEnd[0] == 0 && "Buffer is not null terminated!");
BufferStart = BufStart;
BufferEnd = BufEnd;
- MustDeleteBuffer = false;
}
//===----------------------------------------------------------------------===//
// MemoryBufferMem implementation.
//===----------------------------------------------------------------------===//
+/// CopyStringRef - Copies contents of a StringRef into a block of memory and
+/// null-terminates it.
+static void CopyStringRef(char *Memory, StringRef Data) {
+ memcpy(Memory, Data.data(), Data.size());
+ Memory[Data.size()] = 0; // Null terminate string.
+}
+
+/// GetNamedBuffer - Allocates a new MemoryBuffer with Name copied after it.
+template <typename T>
+static T* GetNamedBuffer(StringRef Buffer, StringRef Name) {
+ char *Mem = static_cast<char*>(operator new(sizeof(T) + Name.size() + 1));
+ CopyStringRef(Mem + sizeof(T), Name);
+ return new (Mem) T(Buffer);
+}
+
namespace {
+/// MemoryBufferMem - Named MemoryBuffer pointing to a block of memory.
class MemoryBufferMem : public MemoryBuffer {
- std::string FileID;
public:
- MemoryBufferMem(const char *Start, const char *End, const char *FID)
- : FileID(FID) {
- init(Start, End);
+ MemoryBufferMem(StringRef InputData) {
+ init(InputData.begin(), InputData.end());
}
-
+
virtual const char *getBufferIdentifier() const {
- return FileID.c_str();
+ // The name is stored after the class itself.
+ return reinterpret_cast<const char*>(this + 1);
}
};
}
/// getMemBuffer - Open the specified memory range as a MemoryBuffer. Note
/// that EndPtr[0] must be a null byte and be accessible!
-MemoryBuffer *MemoryBuffer::getMemBuffer(const char *StartPtr,
- const char *EndPtr,
- const char *BufferName) {
- return new MemoryBufferMem(StartPtr, EndPtr, BufferName);
+MemoryBuffer *MemoryBuffer::getMemBuffer(StringRef InputData,
+ StringRef BufferName) {
+ return GetNamedBuffer<MemoryBufferMem>(InputData, BufferName);
+}
+
+/// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
+/// copying the contents and taking ownership of it. This has no requirements
+/// on EndPtr[0].
+MemoryBuffer *MemoryBuffer::getMemBufferCopy(StringRef InputData,
+ StringRef BufferName) {
+ MemoryBuffer *Buf = getNewUninitMemBuffer(InputData.size(), BufferName);
+ if (!Buf) return 0;
+ memcpy(const_cast<char*>(Buf->getBufferStart()), InputData.data(),
+ InputData.size());
+ return Buf;
}
/// getNewUninitMemBuffer - 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.
-MemoryBuffer *MemoryBuffer::getNewUninitMemBuffer(unsigned Size,
- const char *BufferName) {
- char *Buf = new char[Size+1];
- Buf[Size] = 0;
- MemoryBufferMem *SB = new MemoryBufferMem(Buf, Buf+Size, BufferName);
- // The memory for this buffer is owned by the MemoryBuffer.
- SB->MustDeleteBuffer = true;
- return SB;
+/// that is not initialized. Note that the caller should initialize the
+/// memory allocated by this method. The memory is owned by the MemoryBuffer
+/// object.
+MemoryBuffer *MemoryBuffer::getNewUninitMemBuffer(size_t Size,
+ StringRef BufferName) {
+ // Allocate space for the MemoryBuffer, the data and the name. It is important
+ // that MemoryBuffer and data are aligned so PointerIntPair works with them.
+ size_t AlignedStringLen =
+ RoundUpToAlignment(sizeof(MemoryBufferMem) + BufferName.size() + 1,
+ sizeof(void*)); // TODO: Is sizeof(void*) enough?
+ size_t RealLen = AlignedStringLen + Size + 1;
+ char *Mem = static_cast<char*>(operator new(RealLen, std::nothrow));
+ if (!Mem) return 0;
+
+ // The name is stored after the class itself.
+ CopyStringRef(Mem + sizeof(MemoryBufferMem), BufferName);
+
+ // The buffer begins after the name and must be aligned.
+ char *Buf = Mem + AlignedStringLen;
+ Buf[Size] = 0; // Null terminate buffer.
+
+ return new (Mem) MemoryBufferMem(StringRef(Buf, Size));
}
/// 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.
-MemoryBuffer *MemoryBuffer::getNewMemBuffer(unsigned Size,
- const char *BufferName) {
+MemoryBuffer *MemoryBuffer::getNewMemBuffer(size_t Size, StringRef BufferName) {
MemoryBuffer *SB = getNewUninitMemBuffer(Size, BufferName);
- memset(const_cast<char*>(SB->getBufferStart()), 0, Size+1);
+ if (!SB) return 0;
+ memset(const_cast<char*>(SB->getBufferStart()), 0, Size);
return SB;
}
+/// 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. If stdin is empty, this API (unlike getSTDIN)
+/// returns an empty buffer.
+MemoryBuffer *MemoryBuffer::getFileOrSTDIN(StringRef Filename,
+ std::string *ErrStr,
+ int64_t FileSize,
+ struct stat *FileInfo) {
+ if (Filename == "-")
+ return getSTDIN(ErrStr);
+ return getFile(Filename, ErrStr, FileSize, FileInfo);
+}
+
+MemoryBuffer *MemoryBuffer::getFileOrSTDIN(const char *Filename,
+ std::string *ErrStr,
+ int64_t FileSize,
+ struct stat *FileInfo) {
+ if (strcmp(Filename, "-") == 0)
+ return getSTDIN(ErrStr);
+ return getFile(Filename, ErrStr, FileSize, FileInfo);
+}
+
//===----------------------------------------------------------------------===//
-// MemoryBufferMMapFile implementation.
+// MemoryBuffer::getFile implementation.
//===----------------------------------------------------------------------===//
namespace {
-class MemoryBufferMMapFile : public MemoryBuffer {
- sys::MappedFile File;
+/// MemoryBufferMMapFile - This represents a file that was mapped in with the
+/// sys::Path::MapInFilePages method. When destroyed, it calls the
+/// sys::Path::UnMapFilePages method.
+class MemoryBufferMMapFile : public MemoryBufferMem {
public:
- MemoryBufferMMapFile(const sys::Path &Filename);
-
- virtual const char *getBufferIdentifier() const {
- return File.path().c_str();
+ MemoryBufferMMapFile(StringRef Buffer)
+ : MemoryBufferMem(Buffer) { }
+
+ ~MemoryBufferMMapFile() {
+ sys::Path::UnMapFilePages(getBufferStart(), getBufferSize());
}
-
- ~MemoryBufferMMapFile();
};
-}
-MemoryBufferMMapFile::MemoryBufferMMapFile(const sys::Path &Filename) {
- // FIXME: This does an extra stat syscall to figure out the size, but we
- // already know the size!
- bool Failure = File.open(Filename);
- Failure = Failure; // Silence warning in no-asserts mode.
- assert(!Failure && "Can't open file??");
-
- File.map();
-
- size_t Size = File.size();
-
- static unsigned PageSize = sys::Process::GetPageSize();
- assert(((PageSize & (PageSize-1)) == 0) && PageSize &&
- "Page size is not a power of 2!");
-
- // If this file is not an exact multiple of the system page size (common
- // case), then the OS has zero terminated the buffer for us.
- if ((Size & (PageSize-1))) {
- init(File.charBase(), File.charBase()+Size);
- } else {
- // Otherwise, we allocate a new memory buffer and copy the data over
- initCopyOf(File.charBase(), File.charBase()+Size);
-
- // No need to keep the file mapped any longer.
- File.unmap();
- }
+/// FileCloser - RAII object to make sure an FD gets closed properly.
+class FileCloser {
+ int FD;
+public:
+ explicit FileCloser(int FD) : FD(FD) {}
+ ~FileCloser() { ::close(FD); }
+};
}
-MemoryBufferMMapFile::~MemoryBufferMMapFile() {
- File.unmap();
+MemoryBuffer *MemoryBuffer::getFile(StringRef Filename, std::string *ErrStr,
+ int64_t FileSize, struct stat *FileInfo) {
+ SmallString<256> PathBuf(Filename.begin(), Filename.end());
+ return MemoryBuffer::getFile(PathBuf.c_str(), ErrStr, FileSize, FileInfo);
}
-//===----------------------------------------------------------------------===//
-// MemoryBuffer::getFile implementation.
-//===----------------------------------------------------------------------===//
-
-MemoryBuffer *MemoryBuffer::getFile(const char *FilenameStart, unsigned FnSize,
- int64_t FileSize) {
- sys::PathWithStatus P(FilenameStart, FnSize);
-#if 1
- return new MemoryBufferMMapFile(P);
-#else
- // FIXME: We need an efficient and portable method to open a file and then use
- // 'read' to copy the bits out. The unix implementation is below. This is
- // an important optimization for clients that want to open large numbers of
- // small files (using mmap on everything can easily exhaust address space!).
-
- // If the user didn't specify a filesize, do a stat to find it.
- if (FileSize == -1) {
- const sys::FileStatus *FS = P.getFileStatus();
- if (FS == 0) return 0; // Error stat'ing file.
-
- FileSize = FS->fileSize;
+MemoryBuffer *MemoryBuffer::getFile(const char *Filename, std::string *ErrStr,
+ int64_t FileSize, struct stat *FileInfo) {
+ int OpenFlags = O_RDONLY;
+#ifdef O_BINARY
+ OpenFlags |= O_BINARY; // Open input file in binary mode on win32.
+#endif
+ int FD = ::open(Filename, OpenFlags);
+ if (FD == -1) {
+ if (ErrStr) *ErrStr = sys::StrError();
+ return 0;
}
+ FileCloser FC(FD); // Close FD on return.
- // If the file is larger than some threshold, use mmap, otherwise use 'read'.
- if (FileSize >= 4096*4)
- return new MemoryBufferMMapFile(P);
+ // If we don't know the file size, use fstat to find out. fstat on an open
+ // file descriptor is cheaper than stat on a random path.
+ if (FileSize == -1 || FileInfo) {
+ struct stat MyFileInfo;
+ struct stat *FileInfoPtr = FileInfo? FileInfo : &MyFileInfo;
+
+ // TODO: This should use fstat64 when available.
+ if (fstat(FD, FileInfoPtr) == -1) {
+ if (ErrStr) *ErrStr = sys::StrError();
+ return 0;
+ }
+ FileSize = FileInfoPtr->st_size;
+ }
- MemoryBuffer *SB = getNewUninitMemBuffer(FileSize, FilenameStart);
- char *BufPtr = const_cast<char*>(SB->getBufferStart());
- int FD = ::open(FilenameStart, O_RDONLY);
- if (FD == -1) {
- delete SB;
+ // If the file is large, try to use mmap to read it in. We don't use mmap
+ // for small files, because this can severely fragment our address space. Also
+ // don't try to map files that are exactly a multiple of the system page size,
+ // as the file would not have the required null terminator.
+ //
+ // FIXME: Can we just mmap an extra page in the latter case?
+ if (FileSize >= 4096*4 &&
+ (FileSize & (sys::Process::GetPageSize()-1)) != 0) {
+ if (const char *Pages = sys::Path::MapInFilePages(FD, FileSize)) {
+ return GetNamedBuffer<MemoryBufferMMapFile>(StringRef(Pages, FileSize),
+ Filename);
+ }
+ }
+
+ MemoryBuffer *Buf = MemoryBuffer::getNewUninitMemBuffer(FileSize, Filename);
+ if (!Buf) {
+ // Failed to create a buffer.
+ if (ErrStr) *ErrStr = "could not allocate buffer";
return 0;
}
-
- unsigned BytesLeft = FileSize;
+
+ OwningPtr<MemoryBuffer> SB(Buf);
+ char *BufPtr = const_cast<char*>(SB->getBufferStart());
+
+ size_t BytesLeft = FileSize;
while (BytesLeft) {
ssize_t NumRead = ::read(FD, BufPtr, BytesLeft);
- if (NumRead != -1) {
- BytesLeft -= NumRead;
- BufPtr += NumRead;
- } else if (errno == EINTR) {
- // try again
- } else {
- // error reading.
- close(FD);
- delete SB;
+ if (NumRead == -1) {
+ if (errno == EINTR)
+ continue;
+ // Error while reading.
+ if (ErrStr) *ErrStr = sys::StrError();
return 0;
+ } else if (NumRead == 0) {
+ // We hit EOF early, truncate and terminate buffer.
+ Buf->BufferEnd = BufPtr;
+ *BufPtr = 0;
+ return SB.take();
}
+ BytesLeft -= NumRead;
+ BufPtr += NumRead;
}
- close(FD);
-
- return SB;
-#endif
-}
+ return SB.take();
+}
//===----------------------------------------------------------------------===//
// MemoryBuffer::getSTDIN implementation.
//===----------------------------------------------------------------------===//
-namespace {
-class STDINBufferFile : public MemoryBuffer {
-public:
- virtual const char *getBufferIdentifier() const {
- return "<stdin>";
- }
-};
-}
-
-MemoryBuffer *MemoryBuffer::getSTDIN() {
- char Buffer[4096*4];
-
- std::vector<char> FileData;
-
+MemoryBuffer *MemoryBuffer::getSTDIN(std::string *ErrStr) {
// Read in all of the data from stdin, we cannot mmap stdin.
- while (size_t ReadBytes = fread(Buffer, 1, 4096*4, stdin))
- FileData.insert(FileData.end(), Buffer, Buffer+ReadBytes);
-
- size_t Size = FileData.size();
- MemoryBuffer *B = new STDINBufferFile();
- B->initCopyOf(&FileData[0], &FileData[Size]);
- return B;
+ //
+ // FIXME: That isn't necessarily true, we should try to mmap stdin and
+ // fallback if it fails.
+ sys::Program::ChangeStdinToBinary();
+
+ const ssize_t ChunkSize = 4096*4;
+ SmallString<ChunkSize> Buffer;
+ ssize_t ReadBytes;
+ // Read into Buffer until we hit EOF.
+ do {
+ Buffer.reserve(Buffer.size() + ChunkSize);
+ ReadBytes = read(0, Buffer.end(), ChunkSize);
+ if (ReadBytes == -1) {
+ if (errno == EINTR) continue;
+ if (ErrStr) *ErrStr = sys::StrError();
+ return 0;
+ }
+ Buffer.set_size(Buffer.size() + ReadBytes);
+ } while (ReadBytes != 0);
+
+ return getMemBufferCopy(Buffer, "<stdin>");
}