2 Copyright (C) 2013-2021 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
22 /** @file src/lib/file_group.cc
23 * @brief FileGroup class.
27 #include "compose.hpp"
29 #include "dcpomatic_assert.h"
30 #include "exceptions.h"
31 #include "file_group.h"
39 /** Construct a FileGroup with no files */
40 FileGroup::FileGroup ()
46 /** Construct a FileGroup with a single file */
47 FileGroup::FileGroup (boost::filesystem::path p)
55 /** Construct a FileGroup with multiple files */
56 FileGroup::FileGroup (vector<boost::filesystem::path> const & p)
65 FileGroup::set_paths (vector<boost::filesystem::path> const & p)
73 /** Ensure that the given path index in the content is the _current_file */
75 FileGroup::ensure_open_path (size_t p) const
77 if (_current_file && _current_path == p) {
83 _current_file->close();
87 _current_file = dcp::File(_paths[_current_path], "rb");
89 throw OpenFileError (_paths[_current_path], errno, OpenFileError::READ);
91 _current_size = boost::filesystem::file_size (_paths[_current_path]);
96 FileGroup::seek (int64_t pos, int whence) const
106 _position = length() - pos;
110 /* Find an offset within one of the files, if _position is within a file */
112 int64_t sub_pos = _position;
113 while (i < _paths.size()) {
114 boost::uintmax_t len = boost::filesystem::file_size (_paths[i]);
115 if (sub_pos < int64_t(len)) {
118 sub_pos -= int64_t(len);
122 if (i < _paths.size()) {
123 ensure_open_path (i);
124 _current_file->seek(sub_pos, SEEK_SET);
126 ensure_open_path (_paths.size() - 1);
127 _current_file->seek(_current_size, SEEK_SET);
134 /** Try to read some data from the current position into a buffer.
135 * @param buffer Buffer to write data into.
136 * @param amount Number of bytes to read.
137 * @return Number of bytes read.
140 FileGroup::read (uint8_t* buffer, int amount) const
142 DCPOMATIC_ASSERT (_current_file);
148 size_t to_read = amount - read;
150 DCPOMATIC_ASSERT (_current_file);
152 auto const current_position = _current_file->tell();
153 if (current_position == -1) {
156 } else if ((current_position + to_read) > _current_size) {
157 to_read = _current_size - current_position;
161 int const this_time = _current_file->read(buffer + read, 1, to_read);
163 _position += this_time;
164 if (read == amount) {
169 if (_current_file->error()) {
170 throw FileError (String::compose("fread error %1", errno), _paths[_current_path]);
174 /* See if there is another file to use */
175 if ((_current_path + 1) >= _paths.size()) {
178 ensure_open_path (_current_path + 1);
186 /** @return Combined length of all the files */
188 FileGroup::length () const
191 for (size_t i = 0; i < _paths.size(); ++i) {
192 len += boost::filesystem::file_size (_paths[i]);