LibWebView: Load content blocker lists from settings

Add a content_blocking.list_paths advanced setting backed by a JSON
array. This lets content blocker list paths avoid splitting one string.
The about:settings editor presents array values as one path per line.
It persists them as arrays.

Load configured paths before command-line paths so temporary lists can
still be appended for a single browser session.

Base/res/ladybird/about-pages/settings.html

@@ -117,7 +117,8 @@
             input[type="search"],
             input[type="text"],
             input[type="url"],
-            select {
+            select,
+            textarea {
                 background-color: var(--input-background-color);
 
                 width: 100%;
@@ -319,10 +320,16 @@
             }
 
             .config-control input[type="text"],
-            .config-control input[type="number"] {
+            .config-control input[type="number"],
+            .config-control textarea {
                 width: 100%;
             }
 
+            .config-control textarea {
+                min-width: 280px;
+                resize: vertical;
+            }
+
             @media (max-width: 600px) {
                 .config-row {
                     grid-template-columns: minmax(0, 1fr);

Base/res/ladybird/about-pages/settings/advanced.js

@@ -24,6 +24,22 @@ function createControl(variable) {
         return control;
     }
 
+    if (variable.type === "array" && variable.elementType === "string") {
+        const input = document.createElement("textarea");
+        input.rows = 3;
+        input.value = Array.isArray(variable.value) ? variable.value.join("\n") : "";
+        input.addEventListener("change", () => {
+            const value = input.value
+                .split(/\r?\n/)
+                .map(entry => entry.trim())
+                .filter(entry => entry.length !== 0);
+
+            sendConfigVariableValue(variable, value);
+        });
+        control.append(input);
+        return control;
+    }
+
     const input = document.createElement("input");
     input.value = variable.value ?? "";
 

Libraries/LibWebView/Application.cpp

@@ -333,8 +333,16 @@ ErrorOr<void> Application::initialize(Main::Arguments const& arguments)
     if (profile_process.has_value())
         profile_process_type = process_type_from_name(*profile_process);
 
+    auto configured_content_blocker_list_paths = m_settings.config_variable_as_string_array(ConfigVariableID::ContentBlockerListPaths);
+
     Vector<ByteString> content_blocker_list_paths_as_byte_strings;
-    TRY(content_blocker_list_paths_as_byte_strings.try_ensure_capacity(content_blocker_list_paths.size()));
+    TRY(content_blocker_list_paths_as_byte_strings.try_ensure_capacity(configured_content_blocker_list_paths.size() + content_blocker_list_paths.size()));
+    for (auto const& path : configured_content_blocker_list_paths) {
+        if (path.is_empty())
+            continue;
+
+        content_blocker_list_paths_as_byte_strings.unchecked_append(path.to_byte_string());
+    }
     for (auto path : content_blocker_list_paths)
         content_blocker_list_paths_as_byte_strings.unchecked_append(path);
 

Libraries/LibWebView/Settings.cpp

@@ -67,6 +67,15 @@ static Array<ConfigVariableDefinition, static_cast<size_t>(ConfigVariableID::Cou
         .title = "Show WebContent process ID in tab titles"sv,
         .description = "Append the active WebContent process ID to each tab title and tooltip."sv,
         .default_value = false,
+        .array_element_type = {},
+    },
+    {
+        .id = ConfigVariableID::ContentBlockerListPaths,
+        .name = "content_blocking.list_paths"sv,
+        .title = "Content blocker list paths"sv,
+        .description = "Load content blocker lists from these filesystem paths on startup, in order."sv,
+        .default_value = JsonArray {},
+        .array_element_type = JsonValue::Type::String,
     },
 } };
 
@@ -90,24 +99,49 @@ static ConfigVariableDefinition const& config_variable_definition(ConfigVariable
     return config_variable_definitions()[static_cast<size_t>(id)];
 }
 
-static bool config_variable_value_matches_type(JsonValue const& default_value, JsonValue const& value)
+static bool json_value_matches_type(JsonValue const& value, JsonValue::Type type)
 {
-    switch (default_value.type()) {
+    switch (type) {
+    case JsonValue::Type::Null:
+        return value.is_null();
     case JsonValue::Type::Bool:
         return value.is_bool();
     case JsonValue::Type::Number:
         return value.is_number();
     case JsonValue::Type::String:
         return value.is_string();
-    case JsonValue::Type::Null:
     case JsonValue::Type::Array:
+        return value.is_array();
     case JsonValue::Type::Object:
-        return value.type() == default_value.type();
+        return value.is_object();
     }
 
     VERIFY_NOT_REACHED();
 }
 
+static bool json_array_contains_only_type(JsonArray const& array, JsonValue::Type type)
+{
+    bool contains_only_type = true;
+
+    array.for_each([&](JsonValue const& value) {
+        if (!json_value_matches_type(value, type))
+            contains_only_type = false;
+    });
+
+    return contains_only_type;
+}
+
+static bool config_variable_value_is_valid(ConfigVariableDefinition const& variable, JsonValue const& value)
+{
+    if (!json_value_matches_type(value, variable.default_value.type()))
+        return false;
+
+    if (variable.default_value.is_array() && variable.array_element_type.has_value())
+        return json_array_contains_only_type(value.as_array(), *variable.array_element_type);
+
+    return true;
+}
+
 Settings Settings::create(Badge<Application>)
 {
     // FIXME: Move this to a generic "Ladybird config directory" helper.
@@ -200,7 +234,7 @@ Settings Settings::create(Badge<Application>)
     if (auto config_variables = settings_json.value().get_object(CONFIG_VARIABLES_KEY); config_variables.has_value()) {
         for (auto const& variable : config_variable_definitions()) {
             if (auto value = config_variables->get(variable.name); value.has_value()) {
-                if (config_variable_value_matches_type(variable.default_value, *value))
+                if (config_variable_value_is_valid(variable, *value))
                     settings.m_config_variables[static_cast<size_t>(variable.id)] = *value;
             }
         }
@@ -651,10 +685,29 @@ bool Settings::config_variable_as_bool(ConfigVariableID id) const
     return *value;
 }
 
+Vector<String> Settings::config_variable_as_string_array(ConfigVariableID id) const
+{
+    auto const& variable = config_variable_definition(id);
+    VERIFY(variable.default_value.is_array());
+
+    auto const& value = config_variable(id);
+    VERIFY(value.is_array());
+
+    Vector<String> values;
+    values.ensure_capacity(value.as_array().size());
+
+    value.as_array().for_each([&](JsonValue const& entry) {
+        if (entry.is_string())
+            values.append(entry.as_string());
+    });
+
+    return values;
+}
+
 void Settings::set_config_variable(ConfigVariableID id, JsonValue value)
 {
     auto const& variable = config_variable_definition(id);
-    if (!config_variable_value_matches_type(variable.default_value, value))
+    if (!config_variable_value_is_valid(variable, value))
         return;
 
     if (m_config_variables[static_cast<size_t>(id)].equals(value))

Libraries/LibWebView/Settings.h

@@ -45,6 +45,7 @@ enum class GlobalPrivacyControl {
 
 enum class ConfigVariableID : u8 {
     ShowWebContentProcessIDInTabTitle,
+    ContentBlockerListPaths,
     Count,
 };
 
@@ -54,6 +55,7 @@ struct ConfigVariableDefinition {
     StringView title;
     StringView description;
     JsonValue default_value;
+    Optional<JsonValue::Type> array_element_type;
 };
 
 WEBVIEW_API ReadonlySpan<ConfigVariableDefinition const> config_variable_definitions();
@@ -134,6 +136,7 @@ public:
 
     JsonValue const& config_variable(ConfigVariableID) const;
     bool config_variable_as_bool(ConfigVariableID) const;
+    Vector<String> config_variable_as_string_array(ConfigVariableID) const;
     void set_config_variable(ConfigVariableID, JsonValue);
     void set_config_variable(StringView name, JsonValue const&);
 

Libraries/LibWebView/WebUI/SettingsUI.cpp

@@ -12,9 +12,9 @@
 
 namespace WebView {
 
-static StringView config_variable_type_to_string(JsonValue const& value)
+static StringView config_variable_type_to_string(JsonValue::Type type)
 {
-    switch (value.type()) {
+    switch (type) {
     case JsonValue::Type::Null:
         return "null"sv;
     case JsonValue::Type::Bool:
@@ -114,7 +114,9 @@ void SettingsUI::load_current_settings()
         variable_object.set("name"sv, variable.name);
         variable_object.set("title"sv, variable.title);
         variable_object.set("description"sv, variable.description);
-        variable_object.set("type"sv, config_variable_type_to_string(variable.default_value));
+        variable_object.set("type"sv, config_variable_type_to_string(variable.default_value.type()));
+        if (variable.array_element_type.has_value())
+            variable_object.set("elementType"sv, config_variable_type_to_string(*variable.array_element_type));
         variable_object.set("defaultValue"sv, variable.default_value);
         variable_object.set("value"sv, WebView::Application::settings().config_variable(variable.id));