/* Copyright 1996,1997,1999,2001,2002,2009,2021 Alain Knaff. * This file is part of mtools. * * Mtools is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Mtools is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Mtools. If not, see . * * Force I/O to be done to complete transfer length * * written by: * * Alain L. Knaff * alain@knaff.lu * */ #include "sysincludes.h" #include "msdos.h" #include "stream.h" static ssize_t force_pio(Stream_t *Stream, char *buf, mt_off_t start, size_t len, ssize_t (*io)(Stream_t *, char *, mt_off_t, size_t)) { ssize_t ret; int done=0; while(len){ ret = io(Stream, buf, start, len); if ( ret <= 0 ){ if (done) return done; else return ret; } assert((size_t)ret <= len); start += (size_t) ret; done += ret; len -= (size_t) ret; buf += ret; } return done; } static ssize_t write_wrapper(Stream_t *Stream, char *buf, mt_off_t start UNUSEDP, size_t len) { return Stream->Class->write(Stream, buf, len); } ssize_t force_write(Stream_t *Stream, char *buf, size_t len) { return force_pio(Stream, buf, 0, len, write_wrapper); } ssize_t force_pwrite(Stream_t *Stream, char *buf, mt_off_t start, size_t len) { return force_pio(Stream, buf, start, len, Stream->Class->pwrite); } ssize_t force_pread(Stream_t *Stream, char *buf, mt_off_t start, size_t len) { return force_pio(Stream, buf, start, len, Stream->Class->pread); }