floss: Update README with newer build instructions

* Bison 3.x.x (tested with 3.0.x, 3.2.x and 3.7.x)

You'll want to download some pre-requisite packages as well. If you're currently

configured for AOSP development, you should have all required packages.

Otherwise, you can use the following apt-get list:

configured for AOSP development, you should have most required packages.

Otherwise, you can use the following apt-get list or use the bootstrap script

(see below) to get a list of packages missing on your system:

```sh

sudo apt-get install repo git-core gnupg flex bison gperf build-essential \

  zip curl zlib1g-dev gcc-multilib g++-multilib \

  x11proto-core-dev libx11-dev lib32z-dev libncurses5 \

  x11proto-core-dev libx11-dev libncurses5 \

  libgl1-mesa-dev libxml2-utils xsltproc unzip liblz4-tool libssl-dev \

  libc++-dev libevent-dev \

  flatbuffers-compiler libflatbuffers1 \

  openssl openssl-dev

  flatbuffers-compiler libflatbuffers1 openssl \

  libflatbuffers-dev libtinyxml2-dev \

  libglib2.0-dev libevent-dev libnss3-dev libdbus-1-dev \

  libprotobuf-dev ninja-build generate-ninja protobuf-compiler \

  libre2-9

```

You will also need a recent-ish version of Rust and Cargo. Please follow the

git clone https://android.googlesource.com/platform/packages/modules/Bluetooth/system

```

Install dependencies (require sudo access). This adds some Ubuntu dependencies

and also installs GN (which is the build tool we're using).

### Use bootstrap.py

`bootstrap.py` is a helper script provided to set up your build environment. It

will set up your build staging directory and also make sure you have all

required system packages to build (should work on Debian and Ubuntu). You will

still need to build some unpackaged dependencies.

To use it:

```sh

cd ~/fluoride/bt

build/install_deps.sh

./bootstrap.py --base-dir=path/to/staging/dir --bt-dir=path/to/bt/dir

```

### Build dependencies

The following third-party dependencies are necessary but currently unavailable

via a package manager. You may have to build these from source and install them

to your local environment.

* libchrome

* modp_b64

We provide a script to produce debian packages for those components, please

follow the instructions in build/dpkg/README.txt.

We provide a script to produce debian packages for those components. Please

see the instructions in build/dpkg/README.txt for more details.

```sh

cd build/dpkg

mkdir -p outdir/{modp_b64,libchrome}

# Build and install modp_b64

pushd modp_b64

./gen-src-pkg.sh $(readlink -f ../outdir/modp_b64)

popd

sudo dpkg -i outdir/modp_b64/*.dpkg

# Build and install libchrome

pushd libchrome

./gen-src-pkg.sh $(readlink -f ../outdir/libchrome)

popd

sudo dpkg -i outdir/libchrome/*.dpkg

```

The googletest packages provided by Debian/Ubuntu (libgmock-dev and

libgtest-dev) do not provide pkg-config files, so you can build your own

googletest using the steps below:

```sh

git clone https://github.com/google/googletest.git -b release-1.10.0

cd googletest        # Main directory of the cloned repository.

mkdir build          # Create a directory to hold the build output.

cd build

cmake ..             # Generate native build scripts for GoogleTest.

sudo make install -DCMAKE_INSTALL_PREFIX=/usr

# Optional steps if pkgconfig isn't installed to desired location

# Modify the source (/usr/lib/x86_64-linux-gnu) and target (/usr/lib) based on

# your local installation.

for f in $(ls /usr/lib/x86_64-linux-gnu/pkgconfig/{gtest,gmock}*); do \

  ln -sf $f /usr/lib/pkgconfig/$(basename $f);

done

```

$ git clone https://github.com/google/googletest.git -b release-1.10.0

$ cd googletest        # Main directory of the cloned repository.

$ mkdir build          # Create a directory to hold the build output.

$ cd build

$ cmake ..             # Generate native build scripts for GoogleTest.

$ sudo make install -DCMAKE_INSTALL_PREFIX=/usr

### Rust dependencies

**Note**: Handled by bootstrap script.

Run the following to install Rust dependencies:

```

cargo install cxxbridge-cmd

```

### Stage your build environment

**Note**: Handled by bootstrap script.

For host build, we depend on a few other repositories:

* [Platform2](https://chromium.googlesource.com/chromiumos/platform2/)

* [Rust crates](https://chromium.googlesource.com/chromiumos/third_party/rust_crates/)

### Build

We provide a build script to automate building assuming you've staged your build

environment already as above.

environment already as above. At this point, make sure you have all the

pre-requisites installed (i.e. bootstrap script and other dependencies above) or

you will see failures. In addition, you may need to set a `--libdir=` if your

libraries are not stored in `/usr/lib64` by default.

```sh

### Run

By default on Linux, we statically link libbluetooth so you can just run the

binary directly:

binary directly. By default, it will try to run on hci0 but you can pass it

--hci=N, where N corresponds to /sys/class/bluetooth/hciN.

```sh

cd ~/fluoride/bt/out/Default

./bluetoothtbd -create-ipc-socket=fluoride

$OUTPUT_DIR/debug/btadapterd --hci=$HCI INIT_gd_hci=true

```

#!/bin/bash

CLANG_PACKAGE=clang

GNSHA1_URL="https://chromium.googlesource.com/chromium/buildtools/\

  +/central/linux64/gn.sha1?format=TEXT"

# Check if clang is already installed on current system

clang_path=`which clang`

if [ -f "$clang_path" ]; then

  # if clang binary is avalable, check its version

  clang_version=$($clang_path --version | grep clang | sed "s/.*version\s*\([0-9]*\.[0-9]*\).*/\1/")

  IFS="." read -ra clang_version_array <<< "$clang_version"

  clang_version_major=${clang_version_array[0]}

  clang_version_minor=${clang_version_array[1]}

  # if the version is greater than 3.5 then do not install clang here

  if [ $clang_version_major -ge 3 ] && [ $clang_version_minor -ge 5 ]; then

    echo "Detected clang $clang_version"

    CLANG_PACKAGE=""

  fi

fi

if [ ! -z "$CLANG_PACKAGE" ]; then

  # Try to find clang from a known list

  for clang_version in 12.0 11.0

  do

    clang_path=`which clang-$clang_version`

    if [ -f "$clang_path" ]; then

      echo "Detected clang-$clang_version"

      CLANG_PACKAGE=""

      break

    fi

  done

fi

if [ ! -z "$CLANG_PACKAGE" ]; then

  echo "clang not found on current system, installing"

  if [ -f /etc/lsb-release ]; then

    # Ubuntu

    ubuntu_version=$(lsb_release --release --short)

    IFS="." read -ra ubuntu_version_array <<< "$ubuntu_version"

    ubuntu_version_major=${ubuntu_version_array[0]}

    ubuntu_version_minor=${ubuntu_version_array[1]}

    if [ $ubuntu_version_major -lt 15 ]; then

      echo "Choose clang-3.8 for Ubuntu 14 and below"

      CLANG_PACKAGE=clang-3.8

    fi

  fi

fi

sudo apt-get -y install $CLANG_PACKAGE libevent-dev libc++-dev libc++abi-dev \

  ninja-build libflatbuffers-dev libtinyxml2-dev

gn_path=`which gn`

if [ -z $gn_path ]; then

  gnsha1=$(curl $GNSHA1_URL | base64 -d)

  wget -O gn http://storage.googleapis.com/chromium-gn/$gnsha1

  chmod a+x ./gn

  sudo mv ./gn /usr/bin/

fi