Optimize bash scripts

build-with-docker.sh

-#!/bin/bash -x
+#!/bin/bash
 
-set -eo pipefail
+set -euo pipefail
 
 EM_VERSION=1.39.18-upstream
 
@@ -10,4 +10,4 @@ docker run \
   -v $PWD:/src \
   -v $PWD/wasm/cache:/emsdk_portable/.data/cache/wasm \
   trzeci/emscripten:$EM_VERSION \
-  sh -c 'bash -x ./build.sh'
+  sh -c 'bash ./build.sh'

build.sh

-#!/bin/bash -x
+#!/bin/bash
 
 set -eo pipefail
 
-ROOT=$PWD
-BUILD_DIR=$ROOT/build
+SCRIPT_ROOT=$(dirname $0)/wasm/build-scripts
 
 # verify Emscripten version
 emcc -v
 # build x264
-$ROOT/wasm/build-scripts/build-x264.sh $ROOT/third_party/x264 $BUILD_DIR
+$SCRIPT_ROOT/build-x264.sh
 # configure FFmpeg with Emscripten
-$ROOT/wasm/build-scripts/configure.sh $BUILD_DIR
-# # build dependencies
-$ROOT/wasm/build-scripts/make.sh
-# # build ffmpeg.wasm
-$ROOT/wasm/build-scripts/build-ffmpeg.sh $BUILD_DIR
+$SCRIPT_ROOT/configure-ffmpeg.sh
+# build ffmpeg.wasm
+$SCRIPT_ROOT/build-ffmpeg.sh

wasm/build-scripts/build-ffmpeg.sh

-#!/bin/bash -x
+#!/bin/bash
 
 set -eo pipefail
-
-BUILD_DIR=$1
+source $(dirname $0)/var.sh
 
 mkdir -p wasm/dist
-ARGS=(
+emmake make -j
+FLAGS=(
   -I. -I./fftools -I$BUILD_DIR/include
   -Llibavcodec -Llibavdevice -Llibavfilter -Llibavformat -Llibavresample -Llibavutil -Llibpostproc -Llibswscale -Llibswresample -L$BUILD_DIR/lib
-  -Qunused-arguments
-  -o wasm/dist/ffmpeg-core.js fftools/ffmpeg_opt.c fftools/ffmpeg_filter.c fftools/ffmpeg_hw.c fftools/cmdutils.c fftools/ffmpeg.c
+  -Wno-deprecated-declarations -Wno-pointer-sign -Wno-implicit-int-float-conversion -Wno-switch -Wno-parentheses -Qunused-arguments
   -lavdevice -lavfilter -lavformat -lavcodec -lswresample -lswscale -lavutil -lpostproc -lm -lx264 -pthread
-  -O3                                           # optimize code with performance first
-  --closure 1                                   # code size optimization
+  fftools/ffmpeg_opt.c fftools/ffmpeg_filter.c fftools/ffmpeg_hw.c fftools/cmdutils.c fftools/ffmpeg.c
+  -o wasm/dist/ffmpeg-core.js
   -s USE_SDL=2                                  # use SDL2
   -s USE_PTHREADS=1                             # enable pthreads support
   -s PROXY_TO_PTHREAD=1                         # detach main() from browser/UI main thread
@@ -22,5 +21,7 @@ ARGS=(
   -s EXPORTED_FUNCTIONS="[_main, _proxy_main]"  # export main and proxy_main funcs
   -s EXTRA_EXPORTED_RUNTIME_METHODS="[FS, cwrap, ccall, setValue, writeAsciiToMemory]"   # export preamble funcs
   -s INITIAL_MEMORY=1073741824                  # 1073741824 bytes = 1 GB
+  $OPTIM_FLAGS
 )
-emcc "${ARGS[@]}"
+echo "FFMPEG_EM_FLAGS=${FLAGS[@]}"
+emcc "${FLAGS[@]}"

wasm/build-scripts/build-x264.sh

-#!/bin/bash -x
+#!/bin/bash
 
-set -eo pipefail
+set -euo pipefail
+source $(dirname $0)/var.sh
 
-ROOT=$1
-BUILD_DIR=$2
-
-OPT_FLAGS="-O3 --closure 1"
-
-if [[ "$OSTYPE" == "darwin"* ]]; then
-  # As closure compiler requires java 6 and
-  # I don't find a way to install it in github actions
-  OPT_FLAGS="-O3"
-fi
-
-cd $ROOT
-ARGS=(
+X264_PATH=third_party/x264
+FLAGS=(
   --prefix=$BUILD_DIR                                 # install library in a build directory for FFmpeg to include
   --host=i686-gnu                                     # use i686 linux
   --enable-static                                     # enable building static library
   --disable-cli                                       # disable cli tools
   --disable-asm                                       # disable asm optimization
-  --extra-cflags="-s USE_PTHREADS=1 $OPT_FLAGS"  # flags to use pthread and code optimization
+  --extra-cflags="-c -s USE_PTHREADS=1 $OPTIM_FLAGS"  # flags to use pthread and code optimization
 )
-emconfigure ./configure "${ARGS[@]}"
-emmake make install-lib-static -j4
-cd -
+echo "FLAGS=${FLAGS[@]}"
+(cd $X264_PATH && emconfigure ./configure "${FLAGS[@]}")
+emmake make -C $X264_PATH install-lib-static -j

wasm/build-scripts/configure.sh → wasm/build-scripts/configure-ffmpeg.sh

-#!/bin/bash -x
+#!/bin/bash
 
-set -eo pipefail
+set -euo pipefail
+source $(dirname $0)/var.sh
 
-BUILD_DIR=$1
-CFLAGS="-s USE_PTHREADS -I$BUILD_DIR/include -O3 --closure 1"
+CFLAGS="-s USE_PTHREADS=1 -I$BUILD_DIR/include $OPTIM_FLAGS"
 LDFLAGS="$CFLAGS -L$BUILD_DIR/lib"
-ARGS=(
+FLAGS=(
   --target-os=none        # use none to prevent any os specific configurations
   --arch=x86_32           # use x86_32 to achieve minimal architectural optimization
   --enable-cross-compile  # enable cross compile
@@ -17,6 +17,8 @@ ARGS=(
   --enable-gpl            # required by x264
   --enable-libx264        # enable x264
   --disable-debug         # disable debug info, required by closure
+  --disable-runtime-cpudetect   # disable runtime cpu detect
+  --disable-autodetect    # disable external libraries auto detect
   --extra-cflags="$CFLAGS"
   --extra-cxxflags="$CFLAGS"
   --extra-ldflags="$LDFLAGS"
@@ -29,4 +31,5 @@ ARGS=(
   --objcc=emcc
   --dep-cc=emcc
 )
-emconfigure ./configure "${ARGS[@]}"
+echo "FFMPEG_CONFIG_FLAGS=${FLAGS[@]}"
+emconfigure ./configure "${FLAGS[@]}"

wasm/build-scripts/make.sh

-#!/bin/bash -x
-
-set -eo pipefail
-
-emmake make -j4

wasm/build-scripts/var.sh

+#!/bin/bash
+#
+# Common variables for all scripts
+
+set -euo pipefail
+
+# Flags for code optimization, focus on speed instead
+# of size
+OPTIM_FLAGS=(
+  -O3
+)
+
+# Directory to install headers and libraries
+BUILD_DIR=build
+
+if [[ "$OSTYPE" == "linux-gnu"* ]]; then
+  # Use closure complier only in linux environment
+  OPTIM_FLAGS=(
+    "${OPTIM_FLAGS[@]}"
+    --closure 1
+  )
+fi
+
+# Convert array to string
+OPTIM_FLAGS="${OPTIM_FLAGS[@]}"
+
+echo "OPTIM_FLAGS=$OPTIM_FLAGS"
+echo "BUILD_DIR=$BUILD_DIR"