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/* -*- c++ -*- */
/*
* Copyright 2004,2005,2013 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio 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, or (at your option)
* any later version.
*
* GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "file_descriptor_source_impl.h"
#include <gr_io_signature.h>
#include <cstdio>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdexcept>
#include <stdio.h>
#include <string.h>
#ifdef HAVE_IO_H
#include <io.h>
#endif
namespace gr {
namespace blocks {
file_descriptor_source::sptr
file_descriptor_source::make(size_t itemsize, int fd, bool repeat)
{
return gnuradio::get_initial_sptr
(new file_descriptor_source_impl(itemsize, fd, repeat));
}
file_descriptor_source_impl::file_descriptor_source_impl(size_t itemsize,
int fd,
bool repeat)
: gr_sync_block("file_descriptor_source",
gr_make_io_signature(0, 0, 0),
gr_make_io_signature(1, 1, itemsize)),
d_itemsize(itemsize), d_fd(fd), d_repeat(repeat),
d_residue(new unsigned char[itemsize]), d_residue_len (0)
{
}
file_descriptor_source_impl::~file_descriptor_source_impl()
{
close(d_fd);
delete [] d_residue;
}
int
file_descriptor_source_impl::read_items(char *buf, int nitems)
{
assert(nitems > 0);
assert(d_residue_len < d_itemsize);
int nbytes_read = 0;
if(d_residue_len > 0) {
memcpy(buf, d_residue, d_residue_len);
nbytes_read = d_residue_len;
d_residue_len = 0;
}
int r = read(d_fd, buf + nbytes_read,
nitems * d_itemsize - nbytes_read);
if(r <= 0) {
handle_residue(buf, nbytes_read);
return r;
}
r = handle_residue(buf, r + nbytes_read);
if(r == 0) // block until we get something
return read_items(buf, nitems);
return r;
}
int
file_descriptor_source_impl::handle_residue(char *buf, int nbytes_read)
{
assert(nbytes_read >= 0);
int nitems_read = nbytes_read / d_itemsize;
d_residue_len = nbytes_read % d_itemsize;
if(d_residue_len > 0) {
// fprintf (stderr, "handle_residue: %d\n", d_residue_len);
memcpy(d_residue, buf + nbytes_read - d_residue_len, d_residue_len);
}
return nitems_read;
}
int
file_descriptor_source_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
assert(noutput_items > 0);
char *o = (char*)output_items[0];
int nread = 0;
while(1) {
int r = read_items(o, noutput_items - nread);
if(r == -1) {
if(errno == EINTR)
continue;
else {
perror("file_descriptor_source[read]");
return -1;
}
}
else if(r == 0) { // end of file
if(!d_repeat)
break;
else {
flush_residue();
if(lseek(d_fd, 0, SEEK_SET) == -1) {
perror("file_descriptor_source[lseek]");
return -1;
}
}
}
else {
o += r * d_itemsize;
nread += r;
break;
}
}
if(nread == 0) // EOF
return -1;
return nread;
}
} /* namespace blocks */
} /* namespace gr */
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