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/* -*- c++ -*- */
/*
* Copyright 2004,2005,2013 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* SPDX-License-Identifier: GPL-3.0-or-later
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "file_descriptor_source_impl.h"
#include <gnuradio/io_signature.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <boost/format.hpp>
#include <cerrno>
#include <cstdio>
#include <cstring>
#include <stdexcept>
#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::make_block_sptr<file_descriptor_source_impl>(itemsize, fd, repeat);
}
file_descriptor_source_impl::file_descriptor_source_impl(size_t itemsize,
int fd,
bool repeat)
: sync_block("file_descriptor_source",
io_signature::make(0, 0, 0),
io_signature::make(1, 1, itemsize)),
d_itemsize(itemsize),
d_fd(fd),
d_repeat(repeat),
d_residue(itemsize),
d_residue_len(0)
{
}
file_descriptor_source_impl::~file_descriptor_source_impl() { close(d_fd); }
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.data(), 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);
const unsigned 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.data(), 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 {
GR_LOG_ERROR(d_logger,
boost::format("file_descriptor_source[read]: %s") %
strerror(errno));
return -1;
}
} else if (r == 0) { // end of file
if (!d_repeat)
break;
else {
flush_residue();
if (lseek(d_fd, 0, SEEK_SET) == -1) {
GR_LOG_ERROR(d_logger,
boost::format("file_descriptor_source[lseek]: %s") %
strerror(errno));
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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