gecko-dev/servo/README.md

# The Servo Parallel Browser Engine Project

[![Linux Build Status](https://img.shields.io/travis/servo/servo/master.svg?label=Linux%20build)](https://travis-ci.org/servo/servo)  [![Windows Build Status](https://img.shields.io/appveyor/ci/servo/servo/master.svg?label=Windows%20build)](https://ci.appveyor.com/project/servo/servo/branch/master)  [![Changelog #228](https://img.shields.io/badge/changelog-%23228-9E978E.svg)](https://changelog.com/podcast/228)

Servo is a prototype web browser engine written in the
[Rust](https://github.com/rust-lang/rust) language. It is currently developed on
64bit OS X, 64bit Linux, and Android.

Servo welcomes contribution from everyone.  See
[`CONTRIBUTING.md`](CONTRIBUTING.md) and [`HACKING_QUICKSTART.md`](docs/HACKING_QUICKSTART.md)
for help getting started.

Visit the [Servo Project page](https://servo.org/) for news and guides.

## Setting up your environment

Please select your operating system:
* [OS X](#os-x)
* [Debian-based Linuxes](#on-debian-based-linuxes)
* [Fedora](#on-fedora)
* [Arch Linux](#on-arch-linux)
* [openSUSE](#on-opensuse-linux)
* [Gentoo Linux](#on-gentoo-linux)
* [Microsoft Windows](#on-windows-msvc--mingw)
* [Android](#cross-compilation-for-android)

#### OS X
#### On OS X (homebrew)

``` sh
brew install automake pkg-config python cmake yasm
pip install virtualenv
```
#### On OS X (MacPorts)

``` sh
sudo port install python27 py27-virtualenv cmake yasm
```
#### On OS X >= 10.11 (El Capitan), you also have to install OpenSSL

``` sh
brew install openssl

export OPENSSL_INCLUDE_DIR="$(brew --prefix openssl)/include"
export OPENSSL_LIB_DIR="$(brew --prefix openssl)/lib"

./mach build ...
```

If you've already partially compiled servo but forgot to do this step, run `./mach clean`, set the shell variables, and recompile.

#### On Debian-based Linuxes

``` sh
sudo apt install git curl freeglut3-dev autoconf \
    libfreetype6-dev libgl1-mesa-dri libglib2.0-dev xorg-dev \
    gperf g++ build-essential cmake virtualenv python-pip \
    libssl1.0-dev libbz2-dev libosmesa6-dev libxmu6 libxmu-dev \
    libglu1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libdbus-1-dev
```

If you are on **Ubuntu 14.04** and encountered errors on installing these dependencies involving `libcheese`, see [#6158](https://github.com/servo/servo/issues/6158) for a workaround.

If `virtualenv` does not exist, try `python-virtualenv`.

#### On Fedora

``` sh
sudo dnf install curl freeglut-devel libtool gcc-c++ libXi-devel \
    freetype-devel mesa-libGL-devel mesa-libEGL-devel glib2-devel libX11-devel libXrandr-devel gperf \
    fontconfig-devel cabextract ttmkfdir python python-virtualenv python-pip expat-devel \
    rpm-build openssl-devel cmake bzip2-devel libXcursor-devel libXmu-devel mesa-libOSMesa-devel \
    dbus-devel
```
#### On openSUSE Linux
``` sh
sudo zypper install libX11-devel libexpat-devel libbz2-devel Mesa-libEGL-devel Mesa-libGL-devel cabextract cmake \
    dbus-1-devel fontconfig-devel freetype-devel gcc-c++ git glib2-devel gperf \
    harfbuzz-devel libOSMesa-devel libXcursor-devel libXi-devel libXmu-devel libXrandr-devel libopenssl-devel \
    python-pip python-virtualenv rpm-build glu-devel
```
#### On Arch Linux

``` sh
sudo pacman -S --needed base-devel git python2 python2-virtualenv python2-pip mesa cmake bzip2 libxmu glu pkg-config
```
#### On Gentoo Linux

```sh
sudo emerge net-misc/curl media-libs/freeglut \
    media-libs/freetype media-libs/mesa dev-util/gperf \
    dev-python/virtualenv dev-python/pip dev-libs/openssl \
    x11-libs/libXmu media-libs/glu x11-base/xorg-server
```
#### On Windows (MSVC & MinGW)

1. Install Python for Windows (https://www.python.org/downloads/release/python-2711/). The windows x86-64 MSI installer is fine.
You should change the installation to install the "Add python.exe to Path" feature.

2. Install virtualenv.

 In a normal Windows Shell (cmd.exe or "Command Prompt" from the start menu), do:
 ```
pip install virtualenv
```
 If this does not work, you may need to reboot for the changed PATH settings (by the python installer) to take effect.

3. __(MSVC only)__ Install Git for Windows (https://git-scm.com/download/win). DO allow it to add git.exe to the PATH (default
settings for the installer are fine).

4. __(MSVC only)__ Install Visual Studio 2015 Community Edition (https://www.visualstudio.com/). You MUST add "Visual C++" to the
list of installed components. It is not on by default.

5. __(MinGW only)__ Install MSYS2 (https://msys2.github.io/). After you have done so, open an MSYS shell
window and update the core libraries and install new packages. The extra step at the end is to
downgrade GCC to 5.4, as the GCC6 versions in mingw currently fail to compile some of our
dependencies. We are upgrading to a gcc-free build on Windows as soon as possible:

 ```sh
pacman -Su
pacman -Sy git mingw-w64-x86_64-toolchain mingw-w64-x86_64-icu \
    mingw-w64-x86_64-nspr mingw-w64-x86_64-ca-certificates \
    mingw-w64-x86_64-expat mingw-w64-x86_64-cmake tar diffutils patch \
    patchutils make python2-setuptools
export GCC_URL=http://repo.msys2.org/mingw/x86_64/mingw-w64-x86_64-gcc
export GCC_EXT=5.4.0-1-any.pkg.tar.xz
pacman -U --noconfirm $GCC_URL-$GCC_EXT $GCC_URL-ada-$GCC_EXT \
    $GCC_URL-fortran-$GCC_EXT $GCC_URL-libgfortran-$GCC_EXT $GCC_URL-libs-$GCC_EXT \
    $GCC_URL-objc-$GCC_EXT
```

 Add the following line to the end of `.profile` in your home directory:

 ```
export PATH=/c/Python27:/c/Python27/Scripts:$PATH
```

 Now, open a MINGW64 (not MSYS!) shell window, and you should be able to build
servo as usual!

#### Cross-compilation for Android

Pre-installed Android tools are needed. See wiki for
[details](https://github.com/servo/servo/wiki/Building-for-Android)

## The Rust compiler

Servo's build system automatically downloads a Rust compiler to build itself.
This is normally a specific revision of Rust upstream, but sometimes has a
backported patch or two.
If you'd like to know which nightly build of Rust we use, see
[`rust-commit-hash`](https://github.com/servo/servo/blob/master/rust-commit-hash).

## Building

Servo is built with Cargo, the Rust package manager. We also use Mozilla's
Mach tools to orchestrate the build and other tasks.

### Normal build


To build Servo in development mode.  This is useful for development, but
the resulting binary is very slow.

``` sh
git clone https://github.com/servo/servo
cd servo
./mach build --dev
./mach run tests/html/about-mozilla.html
```

Or on Windows MSVC, in a normal Command Prompt (cmd.exe):
``` cmd
git clone https://github.com/servo/servo
cd servo
mach.bat build --dev
```

For benchmarking, performance testing, or
real-world use, add the `--release` flag to create an optimized build:

``` sh
./mach build --release
./mach run --release tests/html/about-mozilla.html
```

### Building for Android target

``` sh
git clone https://github.com/servo/servo
cd servo

export ANDROID_SDK="/path/to/sdk"
export ANDROID_NDK="/path/to/ndk"
export ANDROID_TOOLCHAIN="/path/to/toolchain"
export PATH="$PATH:/path/to/toolchain/bin"

./mach build --release --android
./mach package --release --android
```

Rather than setting the `ANDROID_*` environment variables every time, you can
also create a `.servobuild` file and then edit it to contain the correct paths
to the Android SDK/NDK tools:

```
cp servobuild.example .servobuild
# edit .servobuild
```

## Running

Use `./mach run [url]` to run Servo. Also, don't miss the info on the [browserhtml page](https://github.com/browserhtml/browserhtml) on how to run the Browser.html
full tech demo (it provides a more browser-like experience than just browsing a single
URL with servo).


### Commandline Arguments

- `-p INTERVAL` turns on the profiler and dumps info to the console every
  `INTERVAL` seconds
- `-s SIZE` sets the tile size for painting; defaults to 512
- `-z` disables all graphical output; useful for running JS / layout tests
- `-Z help` displays useful output to debug servo

### Keyboard Shortcuts

- `Ctrl`+`-` zooms out
- `Ctrl`+`=` zooms in
- `Alt`+`left arrow` goes backwards in the history
- `Alt`+`right arrow` goes forwards in the history
- `Esc` exits servo

## Developing

There are lots of mach commands you can use. You can list them with `./mach
--help`.


The generated documentation can be found on http://doc.servo.org/servo/index.html