https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=46702f92ea499d15cb43c7c46ff9ad05f26aec6d
commit 46702f92ea499d15cb43c7c46ff9ad05f26aec6d Author: Xiaofeng Liu <[email protected]> Date: Wed Nov 8 13:21:30 2017 +0100 cygwin: pread() returns non-zero if read beyond EOF NtReadFile returns EOF status but doesn't set information to 0. Set return value explicitly on EOF. Diff: --- winsup/cygwin/fhandler_disk_file.cc | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/winsup/cygwin/fhandler_disk_file.cc b/winsup/cygwin/fhandler_disk_file.cc index bc8fead..2e4cf49 100644 --- a/winsup/cygwin/fhandler_disk_file.cc +++ b/winsup/cygwin/fhandler_disk_file.cc @@ -1529,7 +1529,9 @@ fhandler_disk_file::pread (void *buf, size_t count, off_t offset) goto non_atomic; status = NtReadFile (prw_handle, NULL, NULL, NULL, &io, buf, count, &off, NULL); - if (!NT_SUCCESS (status) && status != STATUS_END_OF_FILE) + if (status == STATUS_END_OF_FILE) + res = 0; + else if (!NT_SUCCESS (status)) { if (pc.isdir ()) { @@ -1557,7 +1559,8 @@ fhandler_disk_file::pread (void *buf, size_t count, off_t offset) __seterrno_from_nt_status (status); return -1; } - res = io.Information; /* Valid on EOF. */ + else + res = io.Information; /* Valid on EOF. */ } else {
