//===----------------------------------------------------------------------===//
#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Config/config.h"
#include "llvm/Support/Errno.h"
#include <cstdio>
#include <cstring>
#include <new>
-#include <sys/stat.h>
#include <sys/types.h>
#if !defined(_MSC_VER) && !defined(__MINGW32__)
#include <unistd.h>
#else
#include <io.h>
-#ifndef S_ISFIFO
-#define S_ISFIFO(x) (0)
#endif
-#endif
-#include <fcntl.h>
using namespace llvm;
//===----------------------------------------------------------------------===//
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,
- bool RequiresNullTerminator) {
- char *Mem = static_cast<char*>(operator new(sizeof(T) + Name.size() + 1));
- CopyStringRef(Mem + sizeof(T), Name);
- return new (Mem) T(Buffer, RequiresNullTerminator);
+namespace {
+struct NamedBufferAlloc {
+ StringRef Name;
+ NamedBufferAlloc(StringRef Name) : Name(Name) {}
+};
+}
+
+void *operator new(size_t N, const NamedBufferAlloc &Alloc) {
+ char *Mem = static_cast<char *>(operator new(N + Alloc.Name.size() + 1));
+ CopyStringRef(Mem + N, Alloc.Name);
+ return Mem;
}
namespace {
init(InputData.begin(), InputData.end(), RequiresNullTerminator);
}
- virtual const char *getBufferIdentifier() const LLVM_OVERRIDE {
+ const char *getBufferIdentifier() const override {
// The name is stored after the class itself.
return reinterpret_cast<const char*>(this + 1);
}
- virtual BufferKind getBufferKind() const LLVM_OVERRIDE {
+ BufferKind getBufferKind() const override {
return MemoryBuffer_Malloc;
}
};
MemoryBuffer *MemoryBuffer::getMemBuffer(StringRef InputData,
StringRef BufferName,
bool RequiresNullTerminator) {
- return GetNamedBuffer<MemoryBufferMem>(InputData, BufferName,
- RequiresNullTerminator);
+ return new (NamedBufferAlloc(BufferName))
+ MemoryBufferMem(InputData, RequiresNullTerminator);
}
/// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
MemoryBuffer *MemoryBuffer::getMemBufferCopy(StringRef InputData,
StringRef BufferName) {
MemoryBuffer *Buf = getNewUninitMemBuffer(InputData.size(), BufferName);
- if (!Buf) return 0;
+ if (!Buf) return nullptr;
memcpy(const_cast<char*>(Buf->getBufferStart()), InputData.data(),
InputData.size());
return Buf;
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.
+ // TODO: Is 16-byte alignment enough? We copy small object files with large
+ // alignment expectations into this buffer.
size_t AlignedStringLen =
- RoundUpToAlignment(sizeof(MemoryBufferMem) + BufferName.size() + 1,
- sizeof(void*)); // TODO: Is sizeof(void*) enough?
+ RoundUpToAlignment(sizeof(MemoryBufferMem) + BufferName.size() + 1, 16);
size_t RealLen = AlignedStringLen + Size + 1;
char *Mem = static_cast<char*>(operator new(RealLen, std::nothrow));
- if (!Mem) return 0;
+ if (!Mem) return nullptr;
// The name is stored after the class itself.
CopyStringRef(Mem + sizeof(MemoryBufferMem), BufferName);
/// the MemoryBuffer object.
MemoryBuffer *MemoryBuffer::getNewMemBuffer(size_t Size, StringRef BufferName) {
MemoryBuffer *SB = getNewUninitMemBuffer(Size, BufferName);
- if (!SB) return 0;
+ if (!SB) return nullptr;
memset(const_cast<char*>(SB->getBufferStart()), 0, Size);
return SB;
}
/// in *ErrStr with a reason. If stdin is empty, this API (unlike getSTDIN)
/// returns an empty buffer.
error_code MemoryBuffer::getFileOrSTDIN(StringRef Filename,
- OwningPtr<MemoryBuffer> &result,
+ std::unique_ptr<MemoryBuffer> &Result,
int64_t FileSize) {
if (Filename == "-")
- return getSTDIN(result);
- return getFile(Filename, result, FileSize);
+ return getSTDIN(Result);
+ return getFile(Filename, Result, FileSize);
}
-error_code MemoryBuffer::getFileOrSTDIN(const char *Filename,
- OwningPtr<MemoryBuffer> &result,
- int64_t FileSize) {
- if (strcmp(Filename, "-") == 0)
- return getSTDIN(result);
- return getFile(Filename, result, FileSize);
-}
//===----------------------------------------------------------------------===//
// MemoryBuffer::getFile implementation.
//===----------------------------------------------------------------------===//
namespace {
-/// 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(StringRef Buffer, bool RequiresNullTerminator)
- : MemoryBufferMem(Buffer, RequiresNullTerminator) { }
+/// \brief Memory maps a file descriptor using sys::fs::mapped_file_region.
+///
+/// This handles converting the offset into a legal offset on the platform.
+class MemoryBufferMMapFile : public MemoryBuffer {
+ sys::fs::mapped_file_region MFR;
+
+ static uint64_t getLegalMapOffset(uint64_t Offset) {
+ return Offset & ~(sys::fs::mapped_file_region::alignment() - 1);
+ }
+
+ static uint64_t getLegalMapSize(uint64_t Len, uint64_t Offset) {
+ return Len + (Offset - getLegalMapOffset(Offset));
+ }
- ~MemoryBufferMMapFile() {
- static int PageSize = sys::process::get_self()->page_size();
+ const char *getStart(uint64_t Len, uint64_t Offset) {
+ return MFR.const_data() + (Offset - getLegalMapOffset(Offset));
+ }
- uintptr_t Start = reinterpret_cast<uintptr_t>(getBufferStart());
- size_t Size = getBufferSize();
- uintptr_t RealStart = Start & ~(PageSize - 1);
- size_t RealSize = Size + (Start - RealStart);
+public:
+ MemoryBufferMMapFile(bool RequiresNullTerminator, int FD, uint64_t Len,
+ uint64_t Offset, error_code EC)
+ : MFR(FD, false, sys::fs::mapped_file_region::readonly,
+ getLegalMapSize(Len, Offset), getLegalMapOffset(Offset), EC) {
+ if (!EC) {
+ const char *Start = getStart(Len, Offset);
+ init(Start, Start + Len, RequiresNullTerminator);
+ }
+ }
- sys::Path::UnMapFilePages(reinterpret_cast<const char*>(RealStart),
- RealSize);
+ const char *getBufferIdentifier() const override {
+ // The name is stored after the class itself.
+ return reinterpret_cast<const char *>(this + 1);
}
- virtual BufferKind getBufferKind() const LLVM_OVERRIDE {
+ BufferKind getBufferKind() const override {
return MemoryBuffer_MMap;
}
};
}
-static error_code getMemoryBufferForStream(int FD,
+static error_code getMemoryBufferForStream(int FD,
StringRef BufferName,
- OwningPtr<MemoryBuffer> &result) {
+ std::unique_ptr<MemoryBuffer> &Result) {
const ssize_t ChunkSize = 4096*4;
SmallString<ChunkSize> Buffer;
ssize_t ReadBytes;
Buffer.set_size(Buffer.size() + ReadBytes);
} while (ReadBytes != 0);
- result.reset(MemoryBuffer::getMemBufferCopy(Buffer, BufferName));
+ Result.reset(MemoryBuffer::getMemBufferCopy(Buffer, BufferName));
return error_code::success();
}
-error_code MemoryBuffer::getFile(StringRef Filename,
- OwningPtr<MemoryBuffer> &result,
+static error_code getFileAux(const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
+ int64_t FileSize,
+ bool RequiresNullTerminator,
+ bool IsVolatileSize);
+
+error_code MemoryBuffer::getFile(Twine Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
int64_t FileSize,
- bool RequiresNullTerminator) {
+ bool RequiresNullTerminator,
+ bool IsVolatileSize) {
// Ensure the path is null terminated.
- SmallString<256> PathBuf(Filename.begin(), Filename.end());
- return MemoryBuffer::getFile(PathBuf.c_str(), result, FileSize,
- RequiresNullTerminator);
+ SmallString<256> PathBuf;
+ StringRef NullTerminatedName = Filename.toNullTerminatedStringRef(PathBuf);
+ return getFileAux(NullTerminatedName.data(), Result, FileSize,
+ RequiresNullTerminator, IsVolatileSize);
}
-error_code MemoryBuffer::getFile(const char *Filename,
- OwningPtr<MemoryBuffer> &result,
- int64_t FileSize,
- bool RequiresNullTerminator) {
- // First check that the "file" is not a directory
- bool is_dir = false;
- error_code err = sys::fs::is_directory(Filename, is_dir);
- if (err)
- return err;
- if (is_dir)
- return make_error_code(errc::is_a_directory);
-
- 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)
- return error_code(errno, posix_category());
-
- error_code ret = getOpenFile(FD, Filename, result, FileSize, FileSize,
- 0, RequiresNullTerminator);
+static error_code getOpenFileImpl(int FD, const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
+ uint64_t FileSize, uint64_t MapSize,
+ int64_t Offset, bool RequiresNullTerminator,
+ bool IsVolatileSize);
+
+static error_code getFileAux(const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result, int64_t FileSize,
+ bool RequiresNullTerminator,
+ bool IsVolatileSize) {
+ int FD;
+ error_code EC = sys::fs::openFileForRead(Filename, FD);
+ if (EC)
+ return EC;
+
+ error_code ret = getOpenFileImpl(FD, Filename, Result, FileSize, FileSize, 0,
+ RequiresNullTerminator, IsVolatileSize);
close(FD);
return ret;
}
size_t MapSize,
off_t Offset,
bool RequiresNullTerminator,
- int PageSize) {
+ int PageSize,
+ bool IsVolatileSize) {
+ // mmap may leave the buffer without null terminator if the file size changed
+ // by the time the last page is mapped in, so avoid it if the file size is
+ // likely to change.
+ if (IsVolatileSize)
+ return false;
+
// We don't use mmap for small files because this can severely fragment our
// address space.
- if (MapSize < 4096*4)
+ if (MapSize < 4 * 4096 || MapSize < (unsigned)PageSize)
return false;
if (!RequiresNullTerminator)
// FIXME: this chunk of code is duplicated, but it avoids a fstat when
// RequiresNullTerminator = false and MapSize != -1.
if (FileSize == size_t(-1)) {
- struct stat FileInfo;
- // TODO: This should use fstat64 when available.
- if (fstat(FD, &FileInfo) == -1) {
- return error_code(errno, posix_category());
- }
- FileSize = FileInfo.st_size;
+ sys::fs::file_status Status;
+ if (sys::fs::status(FD, Status))
+ return false;
+ FileSize = Status.getSize();
}
// If we need a null terminator and the end of the map is inside the file,
return true;
}
-error_code MemoryBuffer::getOpenFile(int FD, const char *Filename,
- OwningPtr<MemoryBuffer> &result,
- uint64_t FileSize, uint64_t MapSize,
- int64_t Offset,
- bool RequiresNullTerminator) {
+static error_code getOpenFileImpl(int FD, const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
+ uint64_t FileSize, uint64_t MapSize,
+ int64_t Offset, bool RequiresNullTerminator,
+ bool IsVolatileSize) {
static int PageSize = sys::process::get_self()->page_size();
// Default is to map the full file.
// 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 == uint64_t(-1)) {
- struct stat FileInfo;
- // TODO: This should use fstat64 when available.
- if (fstat(FD, &FileInfo) == -1) {
- return error_code(errno, posix_category());
- }
-
- // If this is a named pipe or character device, we can't trust the size.
- // Create the memory buffer by copying off the stream.
- if (S_ISFIFO(FileInfo.st_mode) || S_ISCHR(FileInfo.st_mode)) {
- return getMemoryBufferForStream(FD, Filename, result);
- }
-
- FileSize = FileInfo.st_size;
+ sys::fs::file_status Status;
+ error_code EC = sys::fs::status(FD, Status);
+ if (EC)
+ return EC;
+
+ // If this not a file or a block device (e.g. it's a named pipe
+ // or character device), we can't trust the size. Create the memory
+ // buffer by copying off the stream.
+ sys::fs::file_type Type = Status.type();
+ if (Type != sys::fs::file_type::regular_file &&
+ Type != sys::fs::file_type::block_file)
+ return getMemoryBufferForStream(FD, Filename, Result);
+
+ FileSize = Status.getSize();
}
MapSize = FileSize;
}
if (shouldUseMmap(FD, FileSize, MapSize, Offset, RequiresNullTerminator,
- PageSize)) {
- off_t RealMapOffset = Offset & ~(PageSize - 1);
- off_t Delta = Offset - RealMapOffset;
- size_t RealMapSize = MapSize + Delta;
-
- if (const char *Pages = sys::Path::MapInFilePages(FD,
- RealMapSize,
- RealMapOffset)) {
- result.reset(GetNamedBuffer<MemoryBufferMMapFile>(
- StringRef(Pages + Delta, MapSize), Filename, RequiresNullTerminator));
+ PageSize, IsVolatileSize)) {
+ error_code EC;
+ Result.reset(new (NamedBufferAlloc(Filename)) MemoryBufferMMapFile(
+ RequiresNullTerminator, FD, MapSize, Offset, EC));
+ if (!EC)
return error_code::success();
- }
}
MemoryBuffer *Buf = MemoryBuffer::getNewUninitMemBuffer(MapSize, Filename);
return make_error_code(errc::not_enough_memory);
}
- OwningPtr<MemoryBuffer> SB(Buf);
+ std::unique_ptr<MemoryBuffer> SB(Buf);
char *BufPtr = const_cast<char*>(SB->getBufferStart());
size_t BytesLeft = MapSize;
return error_code(errno, posix_category());
}
if (NumRead == 0) {
- assert(0 && "We got inaccurate FileSize value or fstat reported an "
- "invalid file size.");
- *BufPtr = '\0'; // null-terminate at the actual size.
+ memset(BufPtr, 0, BytesLeft); // zero-initialize rest of the buffer.
break;
}
BytesLeft -= NumRead;
BufPtr += NumRead;
}
- result.swap(SB);
+ Result.swap(SB);
return error_code::success();
}
+error_code MemoryBuffer::getOpenFile(int FD, const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
+ uint64_t FileSize,
+ bool RequiresNullTerminator,
+ bool IsVolatileSize) {
+ return getOpenFileImpl(FD, Filename, Result, FileSize, FileSize, 0,
+ RequiresNullTerminator, IsVolatileSize);
+}
+
+error_code MemoryBuffer::getOpenFileSlice(int FD, const char *Filename,
+ std::unique_ptr<MemoryBuffer> &Result,
+ uint64_t MapSize, int64_t Offset,
+ bool IsVolatileSize) {
+ return getOpenFileImpl(FD, Filename, Result, -1, MapSize, Offset, false,
+ IsVolatileSize);
+}
+
//===----------------------------------------------------------------------===//
// MemoryBuffer::getSTDIN implementation.
//===----------------------------------------------------------------------===//
-error_code MemoryBuffer::getSTDIN(OwningPtr<MemoryBuffer> &result) {
+error_code MemoryBuffer::getSTDIN(std::unique_ptr<MemoryBuffer> &Result) {
// Read in all of the data from stdin, we cannot mmap stdin.
//
// FIXME: That isn't necessarily true, we should try to mmap stdin and
// fallback if it fails.
- sys::Program::ChangeStdinToBinary();
+ sys::ChangeStdinToBinary();
- return getMemoryBufferForStream(0, "<stdin>", result);
+ return getMemoryBufferForStream(0, "<stdin>", Result);
}
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