/******************************************************************************* Copyright(C) Jonas 'Sortie' Termansen 2013. This program 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. This program 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 this program. If not, see . ioleast.cpp Sortix functions for reliable reads and writes. *******************************************************************************/ #include #include #include #include "ioleast.h" #if !defined(__sortix__) size_t preadleast(int fd, void* buf, size_t least, size_t max, off_t off) { ssize_t amount = pread(fd, buf, max, off); if ( amount < 0 ) { return 0; } if ( least && !amount ) { return 0; } if ( (size_t) amount < least ) { void* nextbuf = (uint8_t*) buf + amount; size_t nextleast = least - amount; size_t nextmax = max - amount; off_t nextoff = off + amount; amount += preadleast(fd, nextbuf, nextleast, nextmax, nextoff); } return amount; } size_t preadall(int fd, void* buf, size_t count, off_t off) { return preadleast(fd, buf, count, count, off); } size_t pwriteleast(int fd, const void* buf, size_t least, size_t max, off_t off) { ssize_t amount = pwrite(fd, buf, max, off); if ( amount < 0 ) { return 0; } if ( least && !amount ) { return 0; } if ( (size_t) amount < least ) { const void* nextbuf = (const uint8_t*) buf + amount; size_t nextleast = least - amount; size_t nextmax = max - amount; off_t nextoff = off + amount; amount += pwriteleast(fd, nextbuf, nextleast, nextmax, nextoff); } return amount; } size_t pwriteall(int fd, const void* buf, size_t count, off_t off) { return pwriteleast(fd, buf, count, count, off); } #endif