[llvm-commits] CVS: llvm/lib/Support/MemoryBuffer.cpp

[Reid Spencer]

On Sun, 2007-05-06 at 02:25 -0500, Chris Lattner wrote:
> 
> Changes in directory llvm/lib/Support:
> 
> MemoryBuffer.cpp updated: 1.3 -> 1.4
> ---
> Log message:
> 
> Fix MemoryBuffer::getFile to return null if it has an error opening the
> file instead of aborting.
> 
> 
> ---
> Diffs of the changes:  (+20 -8)
> 
>  MemoryBuffer.cpp |   28 ++++++++++++++++++++--------
>  1 files changed, 20 insertions(+), 8 deletions(-)
> 
> 
> Index: llvm/lib/Support/MemoryBuffer.cpp
> diff -u llvm/lib/Support/MemoryBuffer.cpp:1.3 llvm/lib/Support/MemoryBuffer.cpp:1.4
> --- llvm/lib/Support/MemoryBuffer.cpp:1.3	Sun Apr 29 09:43:31 2007
> +++ llvm/lib/Support/MemoryBuffer.cpp	Sun May  6 02:24:46 2007
> @@ -111,7 +111,9 @@
>  class MemoryBufferMMapFile : public MemoryBuffer {
>    sys::MappedFile File;
>  public:
> -  MemoryBufferMMapFile(const sys::Path &Filename);
> +  MemoryBufferMMapFile() {}
> +  
> +  bool open(const sys::Path &Filename);

Shouldn't this have a parameter to receive the error message ?

>    
>    virtual const char *getBufferIdentifier() const {
>      return File.path().c_str();
> @@ -121,12 +123,11 @@
>  };
>  }
>  
> -MemoryBufferMMapFile::MemoryBufferMMapFile(const sys::Path &Filename) {
> +bool MemoryBufferMMapFile::open(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);

This needs to have an error message parameter to receive the error
message.

> -  Failure = Failure;  // Silence warning in no-asserts mode.
> -  assert(!Failure && "Can't open file??");
> +  if (Failure) return true;

This is insufficient. The caller doesn't know why the
MemoryBufferMMapFile couldn't be opened.
>    
>    File.map();
>    
> @@ -147,10 +148,12 @@
>      // No need to keep the file mapped any longer.
>      File.unmap();
>    }
> +  return false;
>  }
>  
>  MemoryBufferMMapFile::~MemoryBufferMMapFile() {
> -  File.unmap();
> +  if (File.isMapped())
> +    File.unmap();
>  }
>  
>  //===----------------------------------------------------------------------===//
> @@ -161,7 +164,11 @@
>                                      int64_t FileSize) {
>    sys::PathWithStatus P(FilenameStart, FnSize);
>  #if 1
> -  return new MemoryBufferMMapFile(P);
> +  MemoryBufferMMapFile *M = new MemoryBufferMMapFile();
> +  if (!M->open(P))
> +    return M;
> +  delete M;
> +  return 0;
>  #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
> @@ -177,8 +184,13 @@
>    }
>    
>    // If the file is larger than some threshold, use mmap, otherwise use 'read'.
> -  if (FileSize >= 4096*4)
> -    return new MemoryBufferMMapFile(P);
> +  if (FileSize >= 4096*4) {
> +    MemoryBufferMMapFile *M = new MemoryBufferMMapFile();
> +    if (!M->open(P))
> +      return M;
> +    delete M;
> +    return 0;
> +  }
>    
>    MemoryBuffer *SB = getNewUninitMemBuffer(FileSize, FilenameStart);
>    char *BufPtr = const_cast<char*>(SB->getBufferStart());
> 
> 
> 
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits