From 2c36754bf748647442c4f44068c267c2192b5d69 Mon Sep 17 00:00:00 2001
From: Paul Rouget <me@paulrouget.com>
Date: Fri, 17 Jul 2020 08:31:26 +0200
Subject: [PATCH] Configure devtools server via preferences

---
 Cargo.lock                     |  1 +
 components/config/opts.rs      | 34 +++++++++++++++++++++++++---------
 components/config/prefs.rs     |  6 ++++++
 components/devtools/Cargo.toml |  1 +
 components/servo/lib.rs        | 12 +++++++++---
 5 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 5b55ecc39d7..67733e2ad10 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1242,6 +1242,7 @@ dependencies = [
  "msg",
  "serde",
  "serde_json",
+ "servo_config",
  "servo_rand",
  "servo_url",
  "time",
diff --git a/components/config/opts.rs b/components/config/opts.rs
index 47d92f986d5..c5ca6907bee 100644
--- a/components/config/opts.rs
+++ b/components/config/opts.rs
@@ -112,9 +112,12 @@ pub struct Opts {
     /// remote Firefox debugger connections.
     pub debugger_port: Option<u16>,
 
-    /// `None` to disable devtools or `Some` with a port number to start a server to listen to
-    /// remote Firefox devtools connections.
-    pub devtools_port: Option<u16>,
+    /// Port number to start a server to listen to remote Firefox devtools connections.
+    /// 0 for random port.
+    pub devtools_port: u16,
+
+    /// Start the devtools server at startup
+    pub devtools_server_enabled: bool,
 
     /// `None` to disable WebDriver or `Some` with a port number to start a server to listen to
     /// remote WebDriver commands.
@@ -482,7 +485,8 @@ pub fn default_opts() -> Opts {
         enable_canvas_antialiasing: true,
         trace_layout: false,
         debugger_port: None,
-        devtools_port: None,
+        devtools_port: 0,
+        devtools_server_enabled: false,
         webdriver_port: None,
         initial_window_size: Size2D::new(1024, 740),
         multiprocess: false,
@@ -802,11 +806,22 @@ pub fn from_cmdline_args(mut opts: Options, args: &[String]) -> ArgumentParsingR
             })
         });
 
-    // Set default port 0 for a random port to be selected.
-    let devtools_port = opt_match.opt_default("devtools", "0").map(|port| {
-        port.parse()
-            .unwrap_or_else(|err| args_fail(&format!("Error parsing option: --devtools ({})", err)))
-    });
+    let (devtools_enabled, devtools_port) = if opt_match.opt_present("devtools") {
+        let port = opt_match
+            .opt_str("devtools")
+            .map(|port| {
+                port.parse().unwrap_or_else(|err| {
+                    args_fail(&format!("Error parsing option: --devtools ({})", err))
+                })
+            })
+            .unwrap_or(pref!(devtools.server.port));
+        (true, port as u16)
+    } else {
+        (
+            pref!(devtools.server.enabled),
+            pref!(devtools.server.port) as u16,
+        )
+    };
 
     let webdriver_port = opt_match.opt_default("webdriver", "7000").map(|port| {
         port.parse().unwrap_or_else(|err| {
@@ -874,6 +889,7 @@ pub fn from_cmdline_args(mut opts: Options, args: &[String]) -> ArgumentParsingR
         trace_layout: debug_options.trace_layout,
         debugger_port: debugger_port,
         devtools_port: devtools_port,
+        devtools_server_enabled: devtools_enabled,
         webdriver_port: webdriver_port,
         initial_window_size: initial_window_size,
         multiprocess: opt_match.opt_present("M"),
diff --git a/components/config/prefs.rs b/components/config/prefs.rs
index 5ac6b19d940..1ecc245ff9f 100644
--- a/components/config/prefs.rs
+++ b/components/config/prefs.rs
@@ -123,6 +123,12 @@ mod gen {
                     },
                 },
             },
+            devtools: {
+                server: {
+                    enabled: bool,
+                    port: i64,
+                },
+            },
             dom: {
                 webgpu: {
                     enabled: bool,
diff --git a/components/devtools/Cargo.toml b/components/devtools/Cargo.toml
index 6a6532df54a..68da8489cb7 100644
--- a/components/devtools/Cargo.toml
+++ b/components/devtools/Cargo.toml
@@ -22,6 +22,7 @@ log = "0.4"
 msg = { path = "../msg" }
 serde = "1.0"
 serde_json = "1.0"
+servo_config = { path = "../config" }
 servo_rand = { path = "../rand" }
 servo_url = { path = "../url" }
 time = "0.1"
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index aa71c8f3309..581619e431a 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -393,9 +393,15 @@ where
         let mem_profiler_chan = profile_mem::Profiler::create(opts.mem_profiler_period);
 
         let debugger_chan = opts.debugger_port.map(|port| debugger::start_server(port));
-        let devtools_chan = opts
-            .devtools_port
-            .map(|port| devtools::start_server(port, embedder_proxy.clone()));
+
+        let devtools_chan = if opts.devtools_server_enabled {
+            Some(devtools::start_server(
+                opts.devtools_port,
+                embedder_proxy.clone(),
+            ))
+        } else {
+            None
+        };
 
         let coordinates = window.get_coordinates();
         let device_pixel_ratio = coordinates.hidpi_factor.get();