diff options
| -rw-r--r-- | winsup/cygwin/fhandler_floppy.cc | 12 | ||||
| -rw-r--r-- | winsup/cygwin/release/2.10.0 | 3 |
2 files changed, 13 insertions, 2 deletions
diff --git a/winsup/cygwin/fhandler_floppy.cc b/winsup/cygwin/fhandler_floppy.cc index de9e163..cca00ba 100644 --- a/winsup/cygwin/fhandler_floppy.cc +++ b/winsup/cygwin/fhandler_floppy.cc @@ -566,11 +566,11 @@ fhandler_dev_floppy::raw_write (const void *ptr, size_t len) /* Align pointers, lengths, etc. */ cplen = MIN (cplen, written); devbufstart += cplen; + if (devbufstart >= devbufend) + devbufstart = devbufend = 0; p += cplen; len -= cplen; bytes_written += cplen; - if (len) - devbufstart = devbufend = 0; } /* As long as there's still something left in the input buffer ... */ while (len) @@ -607,6 +607,14 @@ fhandler_dev_floppy::raw_write (const void *ptr, size_t len) p += cplen; len -= cplen; bytes_written += cplen; + /* If we overwrote, revalidate devbuf. It still contains the + content from the above read/modify/write. Revalidating makes + sure lseek reports the correct position. */ + if (cplen < bytes_per_sector) + { + devbufstart = cplen; + devbufend = bytes_per_sector; + } } return bytes_written; } diff --git a/winsup/cygwin/release/2.10.0 b/winsup/cygwin/release/2.10.0 index 3afc4b7..0c6b406 100644 --- a/winsup/cygwin/release/2.10.0 +++ b/winsup/cygwin/release/2.10.0 @@ -31,3 +31,6 @@ Bug Fixes - Remove a call to fflush from ftell{o}, which may result in wrong offsets. Addresses: https://cygwin.com/ml/cygwin/2017-12/msg00151.html + +- Fix file pointer computation after short writes on block devices. + Addresses: https://cygwin.com/ml/cygwin/2017-12/msg00151.html |