2 files changed, 112 insertions, 0 deletions
diff --git a/src/utility/io.h b/src/utility/io.h
new file mode 100644
index 0000000..ed1f542
--- /dev/null
+++ b/src/utility/io.h
@@ -0,0 +1,68 @@
+#ifndef CHANGE_SRC_UTILITY_IO_H_
+#define CHANGE_SRC_UTILITY_IO_H_
+
+#include <unistd.h>
+#include <dlfcn.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+#include <cstring>
+
+namespace utility {
+
+class FileDescriptorGuard {
+	public:
+		FileDescriptorGuard(const std::string& path) {
+			this->fd_ = open(path.c_str(), O_CREAT | O_WRONLY | O_APPEND);
+
+			if ( !this->fd_ ) {
+				this->fd_ = STDERR_FILENO;
+			}
+		}
+
+		~FileDescriptorGuard() {
+			close(this->fd_);
+		}
+
+		operator int() {
+			return this->fd_;
+		}
+
+	private:
+		int fd_;
+
+};
+
+std::string get_file_name(int fd) {
+	char proc_link[20];
+	char file_name[256];
+
+	snprintf(proc_link, sizeof(proc_link), "/proc/self/fd/%d", fd);
+	const ssize_t name_size = readlink(proc_link, file_name, sizeof(file_name));
+
+	if ( name_size > 0 ) {
+		file_name[name_size] = '\0';
+
+		return std::string(file_name);
+	} else {
+		return std::string();
+	}
+}
+
+bool is_regular_file(int fd) {
+	struct stat fd_stat;
+	fstat(fd, &fd_stat);
+
+	return S_ISREG(fd_stat.st_mode);
+}
+
+bool is_regular_file(const char* path) {
+	struct stat fd_stat;
+	lstat(path, &fd_stat);
+
+	return S_ISREG(fd_stat.st_mode);
+}
+
+}
+
+#endif  // CHANGE_SRC_UTILITY_IO_H_
diff --git a/src/utility/logger.h b/src/utility/logger.h
new file mode 100644
index 0000000..475f33d
--- /dev/null
+++ b/src/utility/logger.h
@@ -0,0 +1,44 @@
+#ifndef CHANGE_SRC_LOGGER_H_
+#define CHANGE_SRC_LOGGER_H_
+
+#include <ext/stdio_filebuf.h>
+
+#include <boost/process.hpp>
+
+#include <iostream>
+
+namespace utility {
+
+class Logger {
+	public:
+		Logger(const int target_fd):
+			buffer_(target_fd, std::ios::out),
+			stream_(&this->buffer_) { }
+
+		void append(const std::string& msg) {
+			this->stream_ << msg << std::endl;
+		}
+
+		// Forward the contents of a given standard output stream to the log target
+		//
+		// While `this->stream_ << stream.rdbuf()` would be more effective it sadly
+		// does not work with `boost::process::pistream` due to a broken pipe error
+		// in conjunction with the required `boost::process::capture_stream` context
+		// flag.
+		//
+		void forward(boost::process::pistream& stream) {
+			this->stream_ << std::string(
+				(std::istreambuf_iterator<char>(stream)),
+				(std::istreambuf_iterator<char>())
+			);
+		}
+
+	private:
+		__gnu_cxx::stdio_filebuf<char> buffer_;
+		std::ostream                   stream_;
+
+};
+
+}
+
+#endif  // CHANGE_SRC_LOGGER_H_