/* * Copyright (c) 2011, 2012, 2013, 2014, 2015 Jonas 'Sortie' Termansen. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * stdio/fread_unlocked.c * Reads data from a FILE. */ #include #include #include #include #include size_t fread_unlocked(void* ptr, size_t element_size, size_t num_elements, FILE* fp) { if ( !(fp->flags & _FILE_READABLE) ) return errno = EBADF, fp->flags |= _FILE_STATUS_ERROR, EOF; unsigned char* buf = (unsigned char*) ptr; size_t count = element_size * num_elements; if ( count == 0 ) return num_elements; if ( fp->buffer_mode == _IONBF ) { if ( !(fp->flags & _FILE_BUFFER_MODE_SET) ) setvbuf_unlocked(fp, NULL, fp->buffer_mode, 0); if ( !fp->read_func ) return errno = EBADF, fp->flags |= _FILE_STATUS_ERROR, 0; if ( fp->flags & _FILE_LAST_WRITE ) fflush_stop_writing_unlocked(fp); fp->flags |= _FILE_LAST_READ; fp->flags &= ~_FILE_STATUS_EOF; size_t sofar = 0; while ( sofar < count ) { size_t request = count - sofar; if ( (size_t) SSIZE_MAX < request ) request = SSIZE_MAX; ssize_t amount = fp->read_func(fp->user, buf + sofar, request); if ( amount < 0 ) return fp->flags |= _FILE_STATUS_ERROR, sofar / num_elements; if ( amount == 0 ) return fp->flags |= _FILE_STATUS_EOF, sofar / num_elements; sofar += amount; } return sofar / element_size; } for ( size_t n = 0; n < num_elements; n++ ) { size_t offset = n * element_size; for ( size_t i = 0; i < element_size; i++ ) { int c = fgetc_unlocked(fp); if ( c == EOF ) return n; buf[offset + i] = (unsigned char) c; } } return num_elements; }