From 553688a983877c20615a4255c1f4c60938b6f744 Mon Sep 17 00:00:00 2001
From: folkert van heusden <mail@vanheusden.com>
Date: Tue, 21 Mar 2023 22:15:27 +0100
Subject: [PATCH] wip

---
 CMakeLists.txt       |  1 +
 disk_backend_nbd.cpp | 44 ++++++++++++++++++++++++++++++++++++++++++++
 disk_backend_nbd.h   | 18 ++++++++++++++++++
 3 files changed, 63 insertions(+)
 create mode 100644 disk_backend_nbd.cpp
 create mode 100644 disk_backend_nbd.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e3bdc7c..55e709f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,6 +16,7 @@ add_executable(
   debugger.cpp
   disk_backend.cpp
   disk_backend_file.cpp
+  disk_backend_nbd.cpp
   error.cpp
   kw11-l.cpp
   loaders.cpp
diff --git a/disk_backend_nbd.cpp b/disk_backend_nbd.cpp
new file mode 100644
index 0000000..3d5d3e9
--- /dev/null
+++ b/disk_backend_nbd.cpp
@@ -0,0 +1,44 @@
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "disk_backend_nbd.h"
+#include "log.h"
+
+#ifdef ESP32
+#include <lwip/sockets.h>
+#else
+#include <sys/socket.h>
+#endif
+
+
+disk_backend_nbd::disk_backend_nbd(const std::string & host, const int port) :
+	fd(socket(AF_INET, SOCK_STREAM, 0))
+{
+	struct addrinfo hints, *res;
+	int status;
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
+	char *host = "esp-942daf.local";
+	char *port = "5556";
+	status = getaddrinfo(host, port, &hints, &res)
+}
+
+disk_backend_nbd::~disk_backend_nbd()
+{
+	close(fd);
+}
+
+bool disk_backend_nbd::read(const off_t offset, const size_t n, uint8_t *const target)
+{
+	DOLOG(debug, false, "disk_backend_nbd::read: read %zu bytes from offset %zu", n, offset);
+
+	return pread(fd, target, n, offset) == ssize_t(n);
+}
+
+bool disk_backend_nbd::write(const off_t offset, const size_t n, const uint8_t *const from)
+{
+	DOLOG(debug, false, "disk_backend_nbd::write: write %zu bytes to offset %zu", n, offset);
+
+	return pwrite(fd, from, n, offset) == ssize_t(n);
+}
diff --git a/disk_backend_nbd.h b/disk_backend_nbd.h
new file mode 100644
index 0000000..0fe8678
--- /dev/null
+++ b/disk_backend_nbd.h
@@ -0,0 +1,18 @@
+#include <string>
+
+#include "disk_backend.h"
+
+
+class disk_backend_nbd : public disk_backend
+{
+private:
+	const int fd { -1 };
+
+public:
+	disk_backend_nbd(const std::string & host, const int port);
+	virtual ~disk_backend_nbd();
+
+	bool read(const off_t offset, const size_t n, uint8_t *const target);
+
+	bool write(const off_t offset, const size_t n, const uint8_t *const from);
+};