Files
external_libcamera/src/cam/buffer_writer.cpp
T
Laurent Pinchart c671cbe622 cam: Limit file write to payload size
The payload size in a captured framebuffer is usually equal to the
buffer size. However, for compressed formats, the payload may be
smaller Only write the payload when capturing to a file.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-08-25 21:57:53 +03:00

97 lines
2.2 KiB
C++

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2019, Google Inc.
*
* buffer_writer.cpp - Buffer writer
*/
#include <fcntl.h>
#include <iomanip>
#include <iostream>
#include <sstream>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
#include "buffer_writer.h"
using namespace libcamera;
BufferWriter::BufferWriter(const std::string &pattern)
: pattern_(pattern)
{
}
BufferWriter::~BufferWriter()
{
for (auto &iter : mappedBuffers_) {
void *memory = iter.second.first;
unsigned int length = iter.second.second;
munmap(memory, length);
}
mappedBuffers_.clear();
}
void BufferWriter::mapBuffer(FrameBuffer *buffer)
{
for (const FrameBuffer::Plane &plane : buffer->planes()) {
void *memory = mmap(NULL, plane.length, PROT_READ, MAP_SHARED,
plane.fd.fd(), 0);
mappedBuffers_[plane.fd.fd()] =
std::make_pair(memory, plane.length);
}
}
int BufferWriter::write(FrameBuffer *buffer, const std::string &streamName)
{
std::string filename;
size_t pos;
int fd, ret = 0;
filename = pattern_;
pos = filename.find_first_of('#');
if (pos != std::string::npos) {
std::stringstream ss;
ss << streamName << "-" << std::setw(6)
<< std::setfill('0') << buffer->metadata().sequence;
filename.replace(pos, 1, ss.str());
}
fd = open(filename.c_str(), O_CREAT | O_WRONLY |
(pos == std::string::npos ? O_APPEND : O_TRUNC),
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
if (fd == -1)
return -errno;
for (unsigned int i = 0; i < buffer->planes().size(); ++i) {
const FrameBuffer::Plane &plane = buffer->planes()[i];
const FrameMetadata::Plane &meta = buffer->metadata().planes[i];
void *data = mappedBuffers_[plane.fd.fd()].first;
unsigned int length = std::min(meta.bytesused, plane.length);
if (meta.bytesused > plane.length)
std::cerr << "payload size " << meta.bytesused
<< " larger than plane size " << plane.length
<< std::endl;
ret = ::write(fd, data, length);
if (ret < 0) {
ret = -errno;
std::cerr << "write error: " << strerror(-ret)
<< std::endl;
break;
} else if (ret != (int)length) {
std::cerr << "write error: only " << ret
<< " bytes written instead of "
<< length << std::endl;
break;
}
}
close(fd);
return ret;
}