Userland/Libraries: Add LibUSBDB library

Simple clone of LibPCIDB to support USB IDs instead of PCI
ones. The format is basically identical, besides a few changes
of the double tab fields.

Userland/Libraries/LibUSBDB/Database.cpp

@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/OwnPtr.h>
+#include <AK/RefPtr.h>
+#include <AK/StringView.h>
+
+#include "Database.h"
+
+namespace USBDB {
+
+RefPtr<Database> Database::open(const String& filename)
+{
+    auto file_or_error = MappedFile::map(filename);
+    if (file_or_error.is_error())
+        return nullptr;
+    auto res = adopt_ref(*new Database(file_or_error.release_value()));
+    if (res->init() != 0)
+        return nullptr;
+    return res;
+}
+
+const StringView Database::get_vendor(u16 vendor_id) const
+{
+    const auto& vendor = m_vendors.get(vendor_id);
+    if (!vendor.has_value())
+        return "";
+    return vendor.value()->name;
+}
+
+const StringView Database::get_device(u16 vendor_id, u16 device_id) const
+{
+    const auto& vendor = m_vendors.get(vendor_id);
+    if (!vendor.has_value()) {
+        return "";
+    }
+    const auto& device = vendor.value()->devices.get(device_id);
+    if (!device.has_value())
+        return "";
+    return device.value()->name;
+}
+
+const StringView Database::get_interface(u16 vendor_id, u16 device_id, u16 interface_id) const
+{
+    const auto& vendor = m_vendors.get(vendor_id);
+    if (!vendor.has_value())
+        return "";
+    const auto& device = vendor.value()->devices.get(device_id);
+    if (!device.has_value())
+        return "";
+    const auto& interface = device.value()->interfaces.get(interface_id);
+    if (!interface.has_value())
+        return "";
+    return interface.value()->name;
+}
+
+const StringView Database::get_class(u8 class_id) const
+{
+    const auto& xclass = m_classes.get(class_id);
+    if (!xclass.has_value())
+        return "";
+    return xclass.value()->name;
+}
+
+const StringView Database::get_subclass(u8 class_id, u8 subclass_id) const
+{
+    const auto& xclass = m_classes.get(class_id);
+    if (!xclass.has_value())
+        return "";
+    const auto& subclass = xclass.value()->subclasses.get(subclass_id);
+    if (!subclass.has_value())
+        return "";
+    return subclass.value()->name;
+}
+
+const StringView Database::get_protocol(u8 class_id, u8 subclass_id, u8 protocol_id) const
+{
+    const auto& xclass = m_classes.get(class_id);
+    if (!xclass.has_value())
+        return "";
+    const auto& subclass = xclass.value()->subclasses.get(subclass_id);
+    if (!subclass.has_value())
+        return "";
+    const auto& protocol = subclass.value()->protocols.get(protocol_id);
+    if (!protocol.has_value())
+        return "";
+    return protocol.value()->name;
+}
+
+int Database::init()
+{
+    if (m_ready)
+        return 0;
+
+    m_view = StringView { m_file->bytes() };
+
+    ParseMode mode = ParseMode::UnknownMode;
+
+    OwnPtr<Vendor> current_vendor {};
+    OwnPtr<Device> current_device {};
+    OwnPtr<Class> current_class {};
+    OwnPtr<Subclass> current_subclass {};
+
+    auto commit_device = [&]() {
+        if (current_device && current_vendor) {
+            auto id = current_device->id;
+            current_vendor->devices.set(id, current_device.release_nonnull());
+        }
+    };
+
+    auto commit_vendor = [&]() {
+        commit_device();
+        if (current_vendor) {
+            auto id = current_vendor->id;
+            m_vendors.set(id, current_vendor.release_nonnull());
+        }
+    };
+
+    auto commit_subclass = [&]() {
+        if (current_subclass && current_class) {
+            auto id = current_subclass->id;
+            current_class->subclasses.set(id, current_subclass.release_nonnull());
+        }
+    };
+
+    auto commit_class = [&]() {
+        commit_subclass();
+        if (current_class) {
+            auto id = current_class->id;
+            m_classes.set(id, current_class.release_nonnull());
+        }
+    };
+
+    auto commit_all = [&]() {
+        commit_vendor();
+        commit_class();
+    };
+
+    auto lines = m_view.split_view('\n');
+
+    for (auto& line : lines) {
+        if (line.length() < 2 || line[0] == '#')
+            continue;
+
+        if (line[0] == 'C') {
+            mode = ParseMode::ClassMode;
+            commit_all();
+        } else if ((line[0] >= '0' && line[0] <= '9') || (line[0] >= 'a' && line[0] <= 'f')) {
+            mode = ParseMode::VendorMode;
+            commit_all();
+        } else if (line[0] != '\t') {
+            mode = ParseMode::UnknownMode;
+            continue;
+        }
+
+        switch (mode) {
+        case ParseMode::VendorMode:
+            if (line[0] != '\t') {
+                commit_vendor();
+                current_vendor = make<Vendor>();
+                current_vendor->id = AK::StringUtils::convert_to_uint_from_hex<u16>(line).value_or(0);
+                current_vendor->name = line.substring_view(6, line.length() - 6);
+            } else if (line[0] == '\t' && line[1] != '\t') {
+                commit_device();
+                current_device = make<Device>();
+                current_device->id = AK::StringUtils::convert_to_uint_from_hex<u16>((line.substring_view(1, line.length() - 1))).value_or(0);
+                current_device->name = line.substring_view(7, line.length() - 7);
+            } else if (line[0] == '\t' && line[1] == '\t') {
+                auto interface = make<Interface>();
+                interface->interface = AK::StringUtils::convert_to_uint_from_hex<u16>((line.substring_view(2, 4))).value_or(0);
+                interface->name = line.substring_view(7, line.length() - 7);
+                current_device->interfaces.set(interface->interface, move(interface));
+            }
+            break;
+        case ParseMode::ClassMode:
+            if (line[0] != '\t') {
+                commit_class();
+                current_class = make<Class>();
+                current_class->id = AK::StringUtils::convert_to_uint_from_hex<u16>((line.substring_view(2, 2))).value_or(0);
+                current_class->name = line.substring_view(6, line.length() - 6);
+            } else if (line[0] == '\t' && line[1] != '\t') {
+                commit_subclass();
+                current_subclass = make<Subclass>();
+                current_subclass->id = AK::StringUtils::convert_to_uint_from_hex<u16>((line.substring_view(1, 2))).value_or(0);
+                current_subclass->name = line.substring_view(5, line.length() - 5);
+            } else if (line[0] == '\t' && line[1] == '\t') {
+                auto protocol = make<Protocol>();
+                protocol->id = AK::StringUtils::convert_to_uint_from_hex<u16>((line.substring_view(2, 2))).value_or(0);
+                protocol->name = line.substring_view(6, line.length() - 6);
+                current_subclass->protocols.set(protocol->id, move(protocol));
+            }
+            break;
+        default:
+            break;
+        }
+    }
+
+    commit_all();
+
+    m_ready = true;
+
+    return 0;
+}
+
+}