Add ImageBinaryWriter implementation

jf-live-writer/include/ImageBinaryWriter.hpp

@@ -0,0 +1,33 @@
+#ifndef BINARYWRITER_HPP
+#define BINARYWRITER_HPP
+
+#include <string>
+
+#include "formats.hpp"
+
+class ImageBinaryWriter {
+
+    const size_t MAX_FILE_BYTES =
+            buffer_config::FILE_MOD * sizeof(BufferBinaryFormat);
+
+    const std::string detector_folder_;
+    std::string latest_filename_;
+
+    std::string current_output_filename_;
+    int output_file_fd_;
+
+    void open_file(const std::string& filename);
+    void close_current_file();
+
+
+public:
+    ImageBinaryWriter(const std::string& detector_folder);
+
+    virtual ~ImageBinaryWriter();
+
+    void write(const uint64_t pulse_id, const BufferBinaryFormat* buffer);
+
+};
+
+
+#endif //BINARYWRITER_HPP

jf-live-writer/src/ImageBinaryWriter.cpp

@@ -0,0 +1,165 @@
+#include "ImageBinaryWriter.hpp"
+
+#include <unistd.h>
+#include <iostream>
+#include "date.h"
+#include <cerrno>
+#include <chrono>
+#include <cstring>
+#include <fcntl.h>
+
+#include "BufferUtils.hpp"
+
+using namespace std;
+
+ImageBinaryWriter::ImageBinaryWriter(
+        const string& detector_folder):
+        detector_folder_(detector_folder),
+        latest_filename_(detector_folder + "/LATEST"),
+        current_output_filename_(""),
+        output_file_fd_(-1)
+{
+}
+
+ImageBinaryWriter::~ImageBinaryWriter()
+{
+    close_current_file();
+}
+
+void ImageBinaryWriter::write(
+        const uint64_t pulse_id,
+        const BufferBinaryFormat* buffer)
+{
+    auto current_frame_file =
+            BufferUtils::get_filename(detector_folder_, module_name_, pulse_id);
+
+    if (current_frame_file != current_output_filename_) {
+        open_file(current_frame_file);
+    }
+
+    size_t n_bytes_offset =
+            BufferUtils::get_file_frame_index(pulse_id) *
+            sizeof(BufferBinaryFormat);
+
+    auto lseek_result = lseek(output_file_fd_, n_bytes_offset, SEEK_SET);
+    if (lseek_result < 0) {
+        stringstream err_msg;
+
+        using namespace date;
+        using namespace chrono;
+        err_msg << "[" << system_clock::now() << "]";
+        err_msg << "[BufferBinaryWriter::write]";
+        err_msg << " Error while lseek on file ";
+        err_msg << current_output_filename_;
+        err_msg << " for n_bytes_offset ";
+        err_msg << n_bytes_offset << ": ";
+        err_msg << strerror(errno) << endl;
+
+        throw runtime_error(err_msg.str());
+    }
+
+    auto n_bytes = ::write(output_file_fd_, buffer, sizeof(BufferBinaryFormat));
+    if (n_bytes < sizeof(BufferBinaryFormat)) {
+        stringstream err_msg;
+
+        using namespace date;
+        using namespace chrono;
+        err_msg << "[" << system_clock::now() << "]";
+        err_msg << "[BufferBinaryWriter::write]";
+        err_msg << " Error while writing to file ";
+        err_msg << current_output_filename_ << ": ";
+        err_msg << strerror(errno) << endl;
+
+        throw runtime_error(err_msg.str());
+    }
+}
+
+void ImageBinaryWriter::open_file(const std::string& filename)
+{
+    close_current_file();
+
+    BufferUtils::create_destination_folder(filename);
+
+    output_file_fd_ = ::open(filename.c_str(), O_WRONLY | O_CREAT,
+                             S_IRWXU | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH);
+    if (output_file_fd_ < 0) {
+        stringstream err_msg;
+
+        using namespace date;
+        using namespace chrono;
+        err_msg << "[" << system_clock::now() << "]";
+        err_msg << "[BinaryWriter::open_file]";
+        err_msg << " Cannot create file ";
+        err_msg << filename << ": ";
+        err_msg << strerror(errno) << endl;
+
+        throw runtime_error(err_msg.str());
+    }
+
+    // TODO: Remove context if test successful.
+
+    /** Setting the buffer file size in advance to try to lower the number of
+        metadata updates on GPFS. */
+    {
+        // TODO: Try instead to use fallocate.
+        if (lseek(output_file_fd_, MAX_FILE_BYTES, SEEK_SET) < 0) {
+            stringstream err_msg;
+
+            using namespace date;
+            using namespace chrono;
+            err_msg << "[" << system_clock::now() << "]";
+            err_msg << "[BufferBinaryWriter::open_file]";
+            err_msg << " Error while lseek on end of file ";
+            err_msg << current_output_filename_;
+            err_msg << " for MAX_FILE_BYTES ";
+            err_msg << MAX_FILE_BYTES << ": ";
+            err_msg << strerror(errno) << endl;
+
+            throw runtime_error(err_msg.str());
+        }
+
+        const uint8_t mark = 255;
+        if(::write(output_file_fd_, &mark, sizeof(mark)) != sizeof(mark)) {
+            stringstream err_msg;
+
+            using namespace date;
+            using namespace chrono;
+            err_msg << "[" << system_clock::now() << "]";
+            err_msg << "[BufferBinaryWriter::open_file]";
+            err_msg << " Error while writing to file ";
+            err_msg << current_output_filename_ << ": ";
+            err_msg << strerror(errno) << endl;
+
+            throw runtime_error(err_msg.str());
+        }
+    }
+
+
+    current_output_filename_ = filename;
+}
+
+void ImageBinaryWriter::close_current_file()
+{
+    if (output_file_fd_ != -1) {
+        if (close(output_file_fd_) < 0) {
+            stringstream err_msg;
+
+            using namespace date;
+            using namespace chrono;
+            err_msg << "[" << system_clock::now() << "]";
+            err_msg << "[BufferBinaryWriter::close_current_file]";
+            err_msg << " Error while closing file ";
+            err_msg << current_output_filename_ << ": ";
+            err_msg << strerror(errno) << endl;
+
+            throw runtime_error(err_msg.str());
+        }
+
+        output_file_fd_ = -1;
+
+        BufferUtils::update_latest_file(
+                latest_filename_, current_output_filename_);
+
+        current_output_filename_ = "";
+    }
+}