Merge branch 'master' of git://git.ucc.asn.au/tpg/acess2

[tpg/acess2.git] / KernelLand / Kernel / vfs / io.c

diff --git a/KernelLand/Kernel/vfs/io.c b/KernelLand/Kernel/vfs/io.c
index 271e920..35c1ebf 100644 (file)
--- a/KernelLand/Kernel/vfs/io.c
+++ b/KernelLand/Kernel/vfs/io.c
@@ -100,16 +100,32 @@ size_t VFS_ReadAt(int FD, Uint64 Offset, size_t Length, void *Buffer)
  */
 size_t VFS_Write(int FD, size_t Length, const void *Buffer)
 {
-       tVFS_Handle     *h;
-       size_t  ret;
-       
-       h = VFS_GetHandle(FD);
+       tVFS_Handle     *h = VFS_GetHandle(FD);
        if(!h) {
                LOG("FD%i is not open", FD);
                errno = EBADF;
                return -1;
        }
        
+       size_t ret = VFS_WriteAt(FD, h->Position, Length, Buffer);
+       if(ret == (size_t)-1)   return -1;
+
+       if( !(h->Node->Type->Flags & VFS_NODETYPEFLAG_STREAM) )
+               h->Position += ret;
+       return ret;
+}
+
+/**
+ * \fn Uint64 VFS_WriteAt(int FD, Uint64 Offset, Uint64 Length, const void *Buffer)
+ * \brief Write data to a file at a given offset
+ */
+size_t VFS_WriteAt(int FD, Uint64 Offset, size_t Length, const void *Buffer)
+{
+       LOG("FD=%i,Offset=%lli,Length=%i,Buffer=%p",
+               FD, Offset, Length, Buffer);
+       tVFS_Handle     *h = VFS_GetHandle(FD);
+       if(!h)  return -1;
+       
        if( !(h->Mode & VFS_OPENFLAG_WRITE) ) {
                LOG("FD%i not opened for writing", FD);
                errno = EBADF;
@@ -121,57 +137,63 @@ size_t VFS_Write(int FD, size_t Length, const void *Buffer)
                return -1;
        }
 
-       if( !h->Node->Type || !h->Node->Type->Write ) {
+       const tVFS_NodeType*    nodetype = h->Node->Type;
+       if(!nodetype || !nodetype->Write) {
                LOG("FD%i has no write method", FD);
                errno = EINTERNAL;
                return 0;
        }
-
-       if( !MM_GetPhysAddr(h->Node->Type->Write) ) {
+       
+       if( !MM_GetPhysAddr(nodetype->Write) ) {
                Log_Error("VFS", "Node type %p(%s) write method is junk %p",
-                       h->Node->Type, h->Node->Type->TypeName,
-                       h->Node->Type->Write);
+                       nodetype, nodetype->TypeName, nodetype->Write);
                errno = EINTERNAL;
                return -1;
        }
        
-       Uint flags = 0;
-       flags |= (h->Mode & VFS_OPENFLAG_NONBLOCK) ? VFS_IOFLAG_NOBLOCK : 0;
-       ret = h->Node->Type->Write(h->Node, h->Position, Length, Buffer, flags);
-       if(ret != Length)       LOG("%i/%i written", ret, Length);
-       if(ret == (size_t)-1)   return -1;
-
-       h->Position += ret;
-       return ret;
-}
-
-/**
- * \fn Uint64 VFS_WriteAt(int FD, Uint64 Offset, Uint64 Length, const void *Buffer)
- * \brief Write data to a file at a given offset
- */
-size_t VFS_WriteAt(int FD, Uint64 Offset, size_t Length, const void *Buffer)
-{
-       tVFS_Handle     *h;
-       size_t  ret;
-       
-       h = VFS_GetHandle(FD);
-       if(!h)  return -1;
-       
-       if( !(h->Mode & VFS_OPENFLAG_WRITE) )   return -1;
-       if( h->Node->Flags & VFS_FFLAG_DIRECTORY )      return -1;
-
-       if(!h->Node->Type || !h->Node->Type->Write)     return 0;
-
-       if( !MM_GetPhysAddr(h->Node->Type->Write) ) {
-               Log_Error("VFS", "Node type %p(%s) write method is junk %p",
-                       h->Node->Type, h->Node->Type->TypeName,
-                       h->Node->Type->Write);
-               return -1;
+       // Bounds checks
+       if( h->Node->Size != (Uint64)-1 && Offset > h->Node->Size ) {
+               Log_Notice("VFS", "Write starting past EOF of FD%x (%lli > %lli)",
+                       FD, Offset, h->Node->Size);
+               //errno = ESPIPE;
+               return 0;
+       }
+       if( Offset + Length > h->Node->Size )
+       {
+               // Going OOB
+               if( !nodetype->Truncate )
+               {
+                       LOG("No .Truncate method, emiting write past EOF");
+               }
+               else if( nodetype->Flags & VFS_NODETYPEFLAG_NOAUTOEXPAND )
+               {
+                       LOG("NOAUTOEXPAND set, truncating length from %i to %i",
+                               Length, h->Node->Size - Offset);
+                       Length = h->Node->Size - Offset;
+               }
+               else if( nodetype->Truncate(h->Node, Offset + Length) != Offset + Length )
+               {
+                       // oh... fail? Truncate to current size
+                       LOG(".Truncate failed, truncating length from %i to %i",
+                               Length, h->Node->Size - Offset);
+                       Length = h->Node->Size - Offset;
+               }
+               else
+               {
+                       // Expansion, node size should now fit
+                       LOG("Expanded file");
+               }
        }
+       
+       // Create flag set
        Uint flags = 0;
        flags |= (h->Mode & VFS_OPENFLAG_NONBLOCK) ? VFS_IOFLAG_NOBLOCK : 0;
-       ret = h->Node->Type->Write(h->Node, Offset, Length, Buffer, flags);
+       
+       // Dispatch the read!
+       size_t ret = nodetype->Write(h->Node, Offset, Length, Buffer, flags);
        if(ret == (size_t)-1)   return -1;
+       if(ret != Length)       LOG("%i/%i written", ret, Length);
+
        return ret;
 }
 
@@ -198,11 +220,14 @@ Uint64 VFS_Tell(int FD)
  */
 int VFS_Seek(int FD, Sint64 Offset, int Whence)
 {
-       tVFS_Handle     *h;
-       
-       h = VFS_GetHandle(FD);
+       tVFS_Handle     *h = VFS_GetHandle(FD);
        if(!h)  return -1;
        
+       if( (h->Node->Type->Flags & VFS_NODETYPEFLAG_STREAM) ) {
+               LOG("Seeking in stream");
+               return -1;
+       }
+       
        // Set relative to current position
        if(Whence == 0) {
                LOG("(FD%x)->Position += %lli", FD, Offset);
@@ -225,15 +250,34 @@ int VFS_Seek(int FD, Sint64 Offset, int Whence)
        return 0;
 }
 
+/*
+ * Truncate/Expand a file's allocation
+ */
+off_t VFS_Truncate(int FD, off_t Size)
+{
+       tVFS_Handle     *h = VFS_GetHandle(FD);
+       if(!h) {
+               errno = EBADF;
+               return -1;
+       }
+       
+       if( !h->Node->Type->Truncate)
+       {
+               Log_Notice("VFS", "Nodetype '%s' doesn't have a Truncate method", h->Node->Type->TypeName);
+               errno = ENOTIMPL;
+               return -1;      
+       }
+       
+       return h->Node->Type->Truncate(h->Node, Size);
+}
+
 /**
  * \fn int VFS_IOCtl(int FD, int ID, void *Buffer)
  * \brief Call an IO Control on a file
  */
 int VFS_IOCtl(int FD, int ID, void *Buffer)
 {
-       tVFS_Handle     *h;
-       
-       h = VFS_GetHandle(FD);
+       tVFS_Handle     *h = VFS_GetHandle(FD);
        if(!h) {
                LOG("FD%i is invalid", FD);
                errno = EINVAL;