1 files changed, 136 insertions, 0 deletions
diff --git a/um/service/src/device.cpp b/um/service/src/device.cpp
new file mode 100644
index 0000000..5643106
--- /dev/null
+++ b/um/service/src/device.cpp
@@ -0,0 +1,136 @@
+// Copyright (c) 2015 Egor Tensin <Egor.Tensin@gmail.com>
+// This file is part of the "Windows 7 drivers" project.
+// For details, see https://github.com/egor-tensin/windows7-drivers.
+// Distributed under the MIT License.
+
+#include "libservice/all.hpp"
+
+#include <Windows.h>
+
+#include <cstddef>
+
+#include <limits>
+#include <stdexcept>
+#include <string>
+#include <system_error>
+#include <utility>
+
+namespace libservice
+{
+    namespace
+    {
+        Handle open_device(const std::string& path)
+        {
+            const auto raw = CreateFileA(
+                path.c_str(),
+                GENERIC_READ | GENERIC_WRITE,
+                0,
+                NULL,
+                OPEN_EXISTING,
+                FILE_ATTRIBUTE_NORMAL,
+                NULL);
+
+            if (INVALID_HANDLE_VALUE == raw)
+            {
+                const auto ec = GetLastError();
+                throw std::system_error(
+                    ec, WindowsErrorCategory::get(), LIBSERVICE_ERROR_PREFIX);
+            }
+
+            return Handle(raw);
+        }
+    }
+
+    Device Device::open(const std::string& path)
+    {
+        return Device(open_device(path));
+    }
+
+    std::size_t Device::get_required_output_size(
+        Code code,
+        const void* in_buf,
+        std::size_t in_buf_size) const
+    {
+        DWORD nbreq;
+
+        if (in_buf_size > std::numeric_limits<DWORD>::max())
+            throw std::range_error("input buffer size is too large");
+
+        std::size_t nbwritten = DeviceIoControl(
+            handle,
+            code,
+            const_cast<void*>(in_buf),
+            static_cast<DWORD>(in_buf_size),
+            NULL,
+            0,
+            &nbreq,
+            NULL);
+
+        if (0 == nbwritten)
+        {
+            const auto ec = GetLastError();
+
+            switch (ec)
+            {
+                case ERROR_MORE_DATA:
+                    return nbreq;
+
+                default:
+                    throw std::system_error(
+                        ec, WindowsErrorCategory::get(), LIBSERVICE_ERROR_PREFIX);
+            }
+        }
+
+        return nbwritten;
+    }
+
+    std::size_t Device::send_control_code(
+        Code code,
+        const void* in_buf,
+        std::size_t in_buf_size,
+        void* out_buf,
+        std::size_t out_buf_size) const
+    {
+        DWORD nbreq;
+
+        if (in_buf_size > std::numeric_limits<DWORD>::max())
+            throw std::range_error("input buffer size is too large");
+        if (out_buf_size > std::numeric_limits<DWORD>::max())
+            throw std::range_error("output buffer size is too large");
+
+        std::size_t nbwritten = DeviceIoControl(
+            handle,
+            code,
+            const_cast<void*>(in_buf),
+            static_cast<DWORD>(in_buf_size),
+            out_buf,
+            static_cast<DWORD>(out_buf_size),
+            &nbreq,
+            NULL);
+
+        if (0 == nbwritten)
+        {
+            const auto ec = GetLastError();
+            throw std::system_error(
+                ec, WindowsErrorCategory::get(), LIBSERVICE_ERROR_PREFIX);
+        }
+
+        return nbwritten;
+    }
+
+    void swap(Device& a, Device& b) LIBSERVICE_NOEXCEPT
+    {
+        a.swap(b);
+    }
+}
+
+namespace std
+{
+    template <>
+    void swap<libservice::Device>(
+        libservice::Device& a,
+        libservice::Device& b)
+    {
+        a.swap(b);
+    }
+}