diff options
Diffstat (limited to 'ghc/lib/std/cbits/writeFile.c')
| -rw-r--r-- | ghc/lib/std/cbits/writeFile.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/ghc/lib/std/cbits/writeFile.c b/ghc/lib/std/cbits/writeFile.c index 5255ea91eb..eed60e9baf 100644 --- a/ghc/lib/std/cbits/writeFile.c +++ b/ghc/lib/std/cbits/writeFile.c @@ -1,7 +1,7 @@ /* * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998 * - * $Id: writeFile.c,v 1.12 1999/12/08 15:47:08 simonmar Exp $ + * $Id: writeFile.c,v 1.13 2000/03/10 15:23:40 simonmar Exp $ * * hPutStr Runtime Support */ @@ -82,15 +82,21 @@ writeBuffer(StgForeignPtr ptr, StgInt bytes) } +/* ToDo: there's currently no way for writeBuf to return both a + * partial write and an indication that the write blocked. It needs + * two calls: one to get the partial result, and the next one to block. + * This matches Unix write/2, but is rather a waste. + */ + StgInt -writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt len) +writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt off, StgInt len) { IOFileObject* fo = (IOFileObject*)ptr; - int count; + int count, total_count; int rc = 0; - char *pBuf = (char *) buf; + char *pBuf = (char *) buf+off; - if (len == 0 ) + if (len == 0) return 0; /* First of all, check if we do need to flush the buffer .. */ @@ -100,10 +106,10 @@ writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt len) if ( fo->buf != NULL && /* buffered and */ (fo->bufWPtr + len < (fo->bufSize)) /* there's room */ ) { - /* Block copying is likely to be cheaper than, flush, followed by write */ - memcpy(((char*)fo->buf + fo->bufWPtr), buf, len); + /* Block copying is likely to be cheaper than flush, followed by write */ + memcpy(((char*)fo->buf + fo->bufWPtr), pBuf, len); fo->bufWPtr += len; - return 0; + return len; } /* If we do overflow, flush current contents of the buffer and directly output the chunk. @@ -120,6 +126,8 @@ writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt len) } } + total_count = 0; + while ((count = ( #ifdef USE_WINSOCK @@ -132,10 +140,14 @@ writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt len) if ( count >= 0 ) { len -= count; pBuf += count; + total_count += count; continue; } else if ( errno == EAGAIN ) { errno = 0; - return FILEOBJ_BLOCKED_WRITE; + if (total_count > 0) + return total_count; /* partial write */ + else + return FILEOBJ_BLOCKED_WRITE; } else if ( errno != EINTR ) { cvtErrno(); stdErrno(); @@ -143,11 +155,12 @@ writeBuf(StgForeignPtr ptr, StgAddr buf, StgInt len) } } - return 0; + total_count += count; + return total_count; } StgInt -writeBufBA(StgForeignPtr ptr, StgByteArray buf, StgInt len) +writeBufBA(StgForeignPtr ptr, StgByteArray buf, StgInt off, StgInt len) { - return (writeBuf(ptr,(StgAddr)buf, len)); + return (writeBuf(ptr,(StgAddr)buf, off, len)); } |