Ladybird+LibWebView: Move WebContent process launcher to LibWebView

This is to allow headless-browser to reuse this code. We have a similar
helper for launching SQLServer from Ladybird.

Ladybird/WebContentView.cpp

@@ -568,53 +568,8 @@ void WebContentView::create_client()
 {
     m_client_state = {};
 
-    int socket_fds[2] {};
+    auto candidate_web_content_paths = get_paths_for_helper_process("WebContent"sv).release_value_but_fixme_should_propagate_errors();
-    MUST(Core::System::socketpair(AF_LOCAL, SOCK_STREAM, 0, socket_fds));
+    auto new_client = launch_web_content_process(candidate_web_content_paths, m_webdriver_content_ipc_path).release_value_but_fixme_should_propagate_errors();
-
-    int ui_fd = socket_fds[0];
-    int wc_fd = socket_fds[1];
-
-    int fd_passing_socket_fds[2] {};
-    MUST(Core::System::socketpair(AF_LOCAL, SOCK_STREAM, 0, fd_passing_socket_fds));
-
-    int ui_fd_passing_fd = fd_passing_socket_fds[0];
-    int wc_fd_passing_fd = fd_passing_socket_fds[1];
-
-    auto child_pid = fork();
-    if (!child_pid) {
-        MUST(Core::System::close(ui_fd_passing_fd));
-        MUST(Core::System::close(ui_fd));
-
-        auto takeover_string = DeprecatedString::formatted("WebContent:{}", wc_fd);
-        MUST(Core::System::setenv("SOCKET_TAKEOVER"sv, takeover_string, true));
-
-        auto webcontent_fd_passing_socket_string = DeprecatedString::number(wc_fd_passing_fd);
-
-        Vector<StringView, 5> arguments {
-            "WebContent"sv,
-            "--webcontent-fd-passing-socket"sv,
-            webcontent_fd_passing_socket_string
-        };
-
-        if (!m_webdriver_content_ipc_path.is_empty()) {
-            arguments.append("--webdriver-content-path"sv);
-            arguments.append(m_webdriver_content_ipc_path);
-        }
-
-        auto result = spawn_helper_process("WebContent"sv, arguments, Core::System::SearchInPath::Yes);
-        if (result.is_error())
-            warnln("Could not launch WebContent: {}", result.error());
-        VERIFY_NOT_REACHED();
-    }
-
-    MUST(Core::System::close(wc_fd_passing_fd));
-    MUST(Core::System::close(wc_fd));
-
-    auto socket = MUST(Core::LocalSocket::adopt_fd(ui_fd));
-    MUST(socket->set_blocking(true));
-
-    auto new_client = MUST(adopt_nonnull_ref_or_enomem(new (nothrow) WebView::WebContentClient(std::move(socket), *this)));
-    new_client->set_fd_passing_socket(MUST(Core::LocalSocket::adopt_fd(ui_fd_passing_fd)));
 
     m_web_content_notifier.setSocket(new_client->socket().fd().value());
     m_web_content_notifier.setEnabled(true);

Userland/Libraries/LibWebView/ViewImplementation.cpp

@@ -124,4 +124,66 @@ void ViewImplementation::run_javascript(StringView js_source)
     client().async_run_javascript(js_source);
 }
 
+#if !defined(AK_OS_SERENITY)
+
+ErrorOr<NonnullRefPtr<WebView::WebContentClient>> ViewImplementation::launch_web_content_process(ReadonlySpan<String> candidate_web_content_paths, StringView webdriver_content_ipc_path)
+{
+    int socket_fds[2] {};
+    TRY(Core::System::socketpair(AF_LOCAL, SOCK_STREAM, 0, socket_fds));
+
+    int ui_fd = socket_fds[0];
+    int wc_fd = socket_fds[1];
+
+    int fd_passing_socket_fds[2] {};
+    TRY(Core::System::socketpair(AF_LOCAL, SOCK_STREAM, 0, fd_passing_socket_fds));
+
+    int ui_fd_passing_fd = fd_passing_socket_fds[0];
+    int wc_fd_passing_fd = fd_passing_socket_fds[1];
+
+    if (auto child_pid = TRY(Core::System::fork()); child_pid == 0) {
+        TRY(Core::System::close(ui_fd_passing_fd));
+        TRY(Core::System::close(ui_fd));
+
+        auto takeover_string = TRY(String::formatted("WebContent:{}", wc_fd));
+        TRY(Core::System::setenv("SOCKET_TAKEOVER"sv, takeover_string, true));
+
+        auto webcontent_fd_passing_socket_string = TRY(String::number(wc_fd_passing_fd));
+
+        Vector<StringView> arguments {
+            "WebContent"sv,
+            "--webcontent-fd-passing-socket"sv,
+            webcontent_fd_passing_socket_string
+        };
+
+        if (!webdriver_content_ipc_path.is_empty()) {
+            TRY(arguments.try_append("--webdriver-content-path"sv));
+            TRY(arguments.try_append(webdriver_content_ipc_path));
+        }
+
+        ErrorOr<void> result;
+        for (auto const& path : candidate_web_content_paths) {
+            result = Core::System::exec(path, arguments, Core::System::SearchInPath::Yes);
+            if (!result.is_error())
+                break;
+        }
+
+        if (result.is_error())
+            warnln("Could not launch any of {}: {}", candidate_web_content_paths, result.error());
+        VERIFY_NOT_REACHED();
+    }
+
+    TRY(Core::System::close(wc_fd_passing_fd));
+    TRY(Core::System::close(wc_fd));
+
+    auto socket = TRY(Core::LocalSocket::adopt_fd(ui_fd));
+    TRY(socket->set_blocking(true));
+
+    auto new_client = TRY(adopt_nonnull_ref_or_enomem(new (nothrow) WebView::WebContentClient(move(socket), *this)));
+    new_client->set_fd_passing_socket(TRY(Core::LocalSocket::adopt_fd(ui_fd_passing_fd)));
+
+    return new_client;
+}
+
+#endif
+
 }

Userland/Libraries/LibWebView/ViewImplementation.h

@@ -117,6 +117,10 @@ protected:
     virtual void create_client() = 0;
     virtual void update_zoom() = 0;
 
+#if !defined(AK_OS_SERENITY)
+    ErrorOr<NonnullRefPtr<WebView::WebContentClient>> launch_web_content_process(ReadonlySpan<String> candidate_web_content_paths, StringView webdriver_content_ipc_path);
+#endif
+
     struct SharedBitmap {
         i32 id { -1 };
         i32 pending_paints { 0 };