cleanup the MappedFile API and comments. This removes and updates

tons of out of date comments (really nothing throws here!) and fixes
some other fairly glaring issues: "size" used to return the size of 
the file *and* change it, depending on how you called it.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49009 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 119 insertions, 118 deletions

diff --git a/lib/System/Unix/MappedFile.inc b/lib/System/Unix/MappedFile.inc
index 546a226..dcfd189 100644
--- a/lib/System/Unix/MappedFile.inc
+++ b/lib/System/Unix/MappedFile.inc
@@ -31,105 +31,109 @@
 #include <sys/stat.h>
 #endif
 
-namespace llvm {
+using namespace llvm;
 using namespace sys;
 
-struct sys::MappedFileInfo {
-  int   FD;
-  off_t Size;
-};
+namespace llvm {
+  namespace sys {
+    struct MappedFileInfo {
+      int   FD;
+      off_t Size;
+    };
+  }
+}
 
 bool MappedFile::initialize(std::string* ErrMsg) {
   int mode = 0;
-  if (options_ & READ_ACCESS) 
-    if (options_ & WRITE_ACCESS)
+  if (Options & READ_ACCESS) 
+    if (Options & WRITE_ACCESS)
       mode = O_RDWR;
     else
       mode = O_RDONLY;
-  else if (options_ & WRITE_ACCESS)
+  else if (Options & WRITE_ACCESS)
     mode = O_WRONLY;
 
-  int FD = ::open(path_.c_str(), mode);
+  int FD = ::open(Path.c_str(), mode);
   if (FD < 0) {
-    MakeErrMsg(ErrMsg, "can't open file '" + path_.toString() + "'");
+    MakeErrMsg(ErrMsg, "can't open file '" + Path.toString() + "'");
     return true;
   } 
-  const FileStatus *Status = path_.getFileStatus(false, ErrMsg);
+  const FileStatus *Status = Path.getFileStatus(false, ErrMsg);
   if (!Status) {
     ::close(FD);
     return true;
   }
-  info_ = new MappedFileInfo;
-  info_->FD = FD;
-  info_->Size = Status->getSize();
+  MapInfo = new MappedFileInfo();
+  MapInfo->FD = FD;
+  MapInfo->Size = Status->getSize();
   return false;
 }
 
 void MappedFile::terminate() {
-  assert(info_ && "MappedFile not initialized");
-  ::close(info_->FD);
-  delete info_;
-  info_ = 0;
+  assert(MapInfo && "MappedFile not initialized");
+  ::close(MapInfo->FD);
+  delete MapInfo;
+  MapInfo = 0;
 }
 
 void MappedFile::unmap() {
-  assert(info_ && "MappedFile not initialized");
-  if (isMapped()) {
-    if (options_ & WRITE_ACCESS)
-      ::msync(base_, info_->Size, MS_SYNC);
-    ::munmap(base_, info_->Size);
-    base_ = 0;  // Mark this as non-mapped.
-  }
+  assert(MapInfo && "MappedFile not initialized");
+  if (!isMapped()) return;
+  
+  if (Options & WRITE_ACCESS)
+    ::msync(BasePtr, MapInfo->Size, MS_SYNC);
+  ::munmap(BasePtr, MapInfo->Size);
+  BasePtr = 0;  // Mark this as non-mapped.
 }
 
 void* MappedFile::map(std::string* ErrMsg) {
-  assert(info_ && "MappedFile not initialized");
-  if (!isMapped()) {
-    int prot = PROT_NONE;
-    int flags = 0;
+  assert(MapInfo && "MappedFile not initialized");
+  if (isMapped()) return BasePtr;
+  
+  int prot = PROT_NONE;
+  int flags = 0;
 #ifdef MAP_FILE
-    flags |= MAP_FILE;
+  flags |= MAP_FILE;
 #endif
-    if (options_ == 0) {
-      prot = PROT_READ;
-      flags = MAP_PRIVATE;
-    } else {
-      if (options_ & READ_ACCESS)
-        prot |= PROT_READ;
-      if (options_ & WRITE_ACCESS)
-        prot |= PROT_WRITE;
-      if (options_ & EXEC_ACCESS)
-        prot |= PROT_EXEC;
-      if (options_ & SHARED_MAPPING)
-        flags |= MAP_SHARED;
-      else
-        flags |= MAP_PRIVATE;
-    }
-    size_t map_size = ((info_->Size / Process::GetPageSize())+1) *
-      Process::GetPageSize();
-
-    base_ = ::mmap(0, map_size, prot, flags, info_->FD, 0);
-    if (base_ == MAP_FAILED) {
-      MakeErrMsg(ErrMsg, "Can't map file:" + path_.toString());
-      return 0;
-    }
+  if (Options == 0) {
+    prot = PROT_READ;
+    flags = MAP_PRIVATE;
+  } else {
+    if (Options & READ_ACCESS)
+      prot |= PROT_READ;
+    if (Options & WRITE_ACCESS)
+      prot |= PROT_WRITE;
+    if (Options & EXEC_ACCESS)
+      prot |= PROT_EXEC;
+    if (Options & SHARED_MAPPING)
+      flags |= MAP_SHARED;
+    else
+      flags |= MAP_PRIVATE;
   }
-  return base_;
+  size_t map_size = ((MapInfo->Size / Process::GetPageSize())+1) *
+    Process::GetPageSize();
+
+  BasePtr = ::mmap(0, map_size, prot, flags, MapInfo->FD, 0);
+  if (BasePtr == MAP_FAILED) {
+    MakeErrMsg(ErrMsg, "Can't map file:" + Path.toString());
+    return 0;
+  }
+  return BasePtr;
 }
 
 size_t MappedFile::size() const {
-  assert(info_ && "MappedFile not initialized");
-  return info_->Size;
+  assert(MapInfo && "MappedFile not initialized");
+  return MapInfo->Size;
 }
 
-bool MappedFile::size(size_t new_size, std::string* ErrMsg) {
-  assert(info_ && "MappedFile not initialized");
+bool MappedFile::resize(size_t new_size, std::string* ErrMsg) {
+  assert(MapInfo && "MappedFile not initialized");
 
   // Take the mapping out of memory
-  this->unmap();
+  unmap();
 
   // Adjust the current size to a page boundary
-  size_t cur_size = ((info_->Size / Process::GetPageSize())+1) *
+  size_t cur_size = ((MapInfo->Size / Process::GetPageSize())+1) *
     Process::GetPageSize();
 
   // Adjust the new_size to a page boundary
@@ -140,15 +144,12 @@ bool MappedFile::size(size_t new_size, std::string* ErrMsg) {
   if (new_size > cur_size) {
     // Ensure we can allocate at least the idodes necessary to handle the
     // file size requested. 
-    if ((off_t)-1 == ::lseek(info_->FD, new_size, SEEK_SET))
+    if ((off_t)-1 == ::lseek(MapInfo->FD, new_size, SEEK_SET))
       return MakeErrMsg(ErrMsg, "Can't lseek: ");
-    if (-1 == ::write(info_->FD, "\0", 1))
+    if (-1 == ::write(MapInfo->FD, "\0", 1))
       return MakeErrMsg(ErrMsg, "Can't write: ");
   }
 
   // Put the mapping back into memory.
-  return this->map(ErrMsg);
+  return map(ErrMsg);
 }
-
-}
-
diff --git a/lib/System/Win32/MappedFile.inc b/lib/System/Win32/MappedFile.inc
index 28dbb98..de8eec3 100644
--- a/lib/System/Win32/MappedFile.inc
+++ b/lib/System/Win32/MappedFile.inc
@@ -28,32 +28,32 @@ struct sys::MappedFileInfo {
 };
 
 bool MappedFile::initialize(std::string* ErrMsg) {
-  assert(!info_);
-  info_ = new MappedFileInfo;
-  info_->hFile = INVALID_HANDLE_VALUE;
-  info_->hMapping = NULL;
-
-  DWORD mode = options_ & WRITE_ACCESS ? GENERIC_WRITE : GENERIC_READ;
-  DWORD disposition = options_ & WRITE_ACCESS ? OPEN_ALWAYS : OPEN_EXISTING;
-  DWORD share = options_ & WRITE_ACCESS ? FILE_SHARE_WRITE : FILE_SHARE_READ;
-  share = options_ & SHARED_MAPPING ? share : 0;
-  info_->hFile = CreateFile(path_.c_str(), mode, share, NULL, disposition,
+  assert(!MapInfo);
+  MapInfo = new MappedFileInfo;
+  MapInfo->hFile = INVALID_HANDLE_VALUE;
+  MapInfo->hMapping = NULL;
+
+  DWORD mode = Options & WRITE_ACCESS ? GENERIC_WRITE : GENERIC_READ;
+  DWORD disposition = Options & WRITE_ACCESS ? OPEN_ALWAYS : OPEN_EXISTING;
+  DWORD share = Options & WRITE_ACCESS ? FILE_SHARE_WRITE : FILE_SHARE_READ;
+  share = Options & SHARED_MAPPING ? share : 0;
+  MapInfo->hFile = CreateFile(Path.c_str(), mode, share, NULL, disposition,
                             FILE_ATTRIBUTE_NORMAL, NULL);
-  if (info_->hFile == INVALID_HANDLE_VALUE) {
-    delete info_;
-    info_ = NULL;
+  if (MapInfo->hFile == INVALID_HANDLE_VALUE) {
+    delete MapInfo;
+    MapInfo = NULL;
     return MakeErrMsg(ErrMsg,
-      std::string("Can't open file: ") + path_.toString());
+      std::string("Can't open file: ") + Path.toString());
   }
 
   LARGE_INTEGER size;
-  if (!GetFileSizeEx(info_->hFile, &size) ||
-      (info_->size = size_t(size.QuadPart), info_->size != size.QuadPart)) {
-    CloseHandle(info_->hFile);
-    delete info_;
-    info_ = NULL;
+  if (!GetFileSizeEx(MapInfo->hFile, &size) ||
+      (MapInfo->size = size_t(size.QuadPart), MapInfo->size != size.QuadPart)) {
+    CloseHandle(MapInfo->hFile);
+    delete MapInfo;
+    MapInfo = NULL;
     return MakeErrMsg(ErrMsg, 
-      std::string("Can't get size of file: ") + path_.toString());
+      std::string("Can't get size of file: ") + Path.toString());
   }
 
   return false;
@@ -61,56 +61,56 @@ bool MappedFile::initialize(std::string* ErrMsg) {
 
 void MappedFile::terminate() {
   unmap();
-  if (info_->hFile != INVALID_HANDLE_VALUE)
-    CloseHandle(info_->hFile);
-  delete info_;
-  info_ = NULL;
+  if (MapInfo->hFile != INVALID_HANDLE_VALUE)
+    CloseHandle(MapInfo->hFile);
+  delete MapInfo;
+  MapInfo = NULL;
 }
 
 void MappedFile::unmap() {
-  assert(info_ && "MappedFile not initialized");
+  assert(MapInfo && "MappedFile not initialized");
   if (isMapped()) {
-    UnmapViewOfFile(base_);
-    base_ = NULL;
+    UnmapViewOfFile(BasePtr);
+    BasePtr = NULL;
   }
-  if (info_->hMapping != INVALID_HANDLE_VALUE) {
-    CloseHandle(info_->hMapping);
-    info_->hMapping = NULL;
+  if (MapInfo->hMapping != INVALID_HANDLE_VALUE) {
+    CloseHandle(MapInfo->hMapping);
+    MapInfo->hMapping = NULL;
   }
 }
 
 void* MappedFile::map(std::string* ErrMsg) {
   if (!isMapped()) {
     DWORD prot = PAGE_READONLY;
-    if (options_ & EXEC_ACCESS)
+    if (Options & EXEC_ACCESS)
       prot = SEC_IMAGE;
-    else if (options_ & WRITE_ACCESS)
+    else if (Options & WRITE_ACCESS)
       prot = PAGE_READWRITE;
-    info_->hMapping = CreateFileMapping(info_->hFile, NULL, prot, 0, 0, NULL);
-    if (info_->hMapping == NULL) {
-      MakeErrMsg(ErrMsg, std::string("Can't map file: ") + path_.toString());
+    MapInfo->hMapping = CreateFileMapping(MapInfo->hFile, NULL, prot, 0, 0, NULL);
+    if (MapInfo->hMapping == NULL) {
+      MakeErrMsg(ErrMsg, std::string("Can't map file: ") + Path.toString());
       return 0;
     }
 
-    prot = (options_ & WRITE_ACCESS) ? FILE_MAP_WRITE : FILE_MAP_READ;
-    base_ = MapViewOfFileEx(info_->hMapping, prot, 0, 0, 0, NULL);
-    if (base_ == NULL) {
-      CloseHandle(info_->hMapping);
-      info_->hMapping = NULL;
-      MakeErrMsg(ErrMsg, std::string("Can't map file: ") + path_.toString());
+    prot = (Options & WRITE_ACCESS) ? FILE_MAP_WRITE : FILE_MAP_READ;
+    BasePtr = MapViewOfFileEx(MapInfo->hMapping, prot, 0, 0, 0, NULL);
+    if (BasePtr == NULL) {
+      CloseHandle(MapInfo->hMapping);
+      MapInfo->hMapping = NULL;
+      MakeErrMsg(ErrMsg, std::string("Can't map file: ") + Path.toString());
       return 0;
     }
   }
-  return base_;
+  return BasePtr;
 }
 
 size_t MappedFile::size() const {
-  assert(info_ && "MappedFile not initialized");
-  return info_->size;
+  assert(MapInfo && "MappedFile not initialized");
+  return MapInfo->size;
 }
 
-bool MappedFile::size(size_t new_size, std::string* ErrMsg) {
-  assert(info_ && "MappedFile not initialized");
+bool MappedFile::resize(size_t new_size, std::string* ErrMsg) {
+  assert(MapInfo && "MappedFile not initialized");
 
   // Take the mapping out of memory.
   unmap();
@@ -120,16 +120,16 @@ bool MappedFile::size(size_t new_size, std::string* ErrMsg) {
   new_size = (new_size + pagesizem1) & ~pagesizem1;
 
   // If the file needs to be extended, do so.
-  if (new_size > info_->size) {
+  if (new_size > MapInfo->size) {
     LARGE_INTEGER eof;
     eof.QuadPart = new_size;
-    if (!SetFilePointerEx(info_->hFile, eof, NULL, FILE_BEGIN))
+    if (!SetFilePointerEx(MapInfo->hFile, eof, NULL, FILE_BEGIN))
       return MakeErrMsg(ErrMsg, 
-        std::string("Can't set end of file: ") + path_.toString());
-    if (!SetEndOfFile(info_->hFile))
+        std::string("Can't set end of file: ") + Path.toString());
+    if (!SetEndOfFile(MapInfo->hFile))
       return MakeErrMsg(ErrMsg, 
-        std::string("Can't set end of file: ") + path_.toString());
-    info_->size = new_size;
+        std::string("Can't set end of file: ") + Path.toString());
+    MapInfo->size = new_size;
   }
 
   // Remap the file.