Enable Emscripten optimizations

Author: saurvs

Diff for: .babelrc

@@ -0,0 +1,3 @@
+{
+  "presets": ["env"]
+}

Diff for: .gitignore

@@ -1 +1,4 @@
-tests/build
+node_modules/
+package-lock.json
+pre.js
+tests/build/

Diff for: .travis.yml

@@ -13,7 +13,7 @@ cache:
 
 before_script:
   - docker run -dit --name emscripten -v $(pwd):/src trzeci/emscripten-slim bash
-  - npm install puppeteer
+  - npm install
 
 script:
   - docker exec -it emscripten bash tests/run.sh --no-test

Diff for: emcc-cvmfs

@@ -1,20 +1,37 @@
 #!/bin/bash
 
+set -e
+
+OUTPUT_JS="a.out.js"
+
+i=1
+while [ "$i" -le "$#" ]; do
+  eval "arg=\${$i}"
+  if [[ $arg == "-o" ]]; then
+    i=$((i + 1))
+    eval "OUTPATH=\${$i}"
+    OUTFILE=$(basename $OUTPATH)
+    if [[ $OUTFILE == *.html || $OUTFILE == *.js ]]; then
+      OUTPUT_JS=$(dirname $OUTPATH)/${OUTFILE%*.*}.js
+    else
+      echo "Please specify either an HTML or JavaScript output." && exit -1
+    fi
+    break
+  fi
+  i=$((i + 1))
+done
+
 SRC_DIR="$( cd "$( dirname "$0" )" && pwd )"
-CVMFS_DIR=$SRC_DIR/cvmfs
 FS_DIR=$SRC_DIR/fs
-THIRD_PARTY_DIR=$SRC_DIR/third_party
+
+$SRC_DIR/generate-pre.sh
 
 emcc $* \
-    -s WASM=0 \
-    --pre-js $THIRD_PARTY_DIR/jsrsasign-all-min.js \
-    --pre-js $THIRD_PARTY_DIR/sha3.js \
-    --pre-js $THIRD_PARTY_DIR/pako_inflate.min.js \
-    --pre-js $THIRD_PARTY_DIR/sql.js \
-    --pre-js $CVMFS_DIR/cvmfs.js \
-    --pre-js $CVMFS_DIR/fetcher.js \
-    --pre-js $CVMFS_DIR/master_keys.js \
-    --pre-js $CVMFS_DIR/repo.js \
-    --pre-js $CVMFS_DIR/util.js \
     --js-library $FS_DIR/library_cvmfs.js \
-    --js-library $FS_DIR/library_fs.js
+    --js-library $FS_DIR/library_fs.js \
+    --pre-js $SRC_DIR/pre.js
+
+OUTPUT_JS_TMP=$OUTPUT_JS.tmp
+cat $SRC_DIR/third_party/sql.js > $OUTPUT_JS_TMP
+cat $OUTPUT_JS >> $OUTPUT_JS_TMP
+mv $OUTPUT_JS_TMP $OUTPUT_JS

Diff for: generate-pre.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+
+set -e
+
+SRC_DIR="$( cd "$( dirname "$0" )" && pwd )"
+CVMFS_DIR=$SRC_DIR/cvmfs
+THIRD_PARTY_DIR=$SRC_DIR/third_party
+PRE_JS=$SRC_DIR/pre.js
+
+FILES_CHANGED=0
+
+pre_files=($CVMFS_DIR/*.js $THIRD_PARTY_DIR/*.js)
+for file in ${pre_files[*]}; do
+  if [[ $file != *sql.js && $file -nt $PRE_JS ]]; then
+    FILES_CHANGED=1
+    break
+  fi
+done
+
+[[ FILES_CHANGED -eq 0 ]] && exit 0
+
+echo "Generating pre.js"
+
+> $PRE_JS
+
+for file in ${pre_files[*]}; do
+  if [[ $file != *sql.js && $file != *sha3.js ]]; then
+    cat $file >> $PRE_JS
+  fi
+done
+
+npx babel $PRE_JS -o $PRE_JS.babel
+mv $PRE_JS.babel $PRE_JS
+
+# somehow, babel messes up transpiling sha3.js correctly, but sha3.js
+# also dosn't crash Emscripten's optimizer, so we can just prepend it
+cat $THIRD_PARTY_DIR/sha3.js >> $PRE_JS

Diff for: package.json

@@ -0,0 +1,7 @@
+{
+  "devDependencies": {
+    "babel-cli": "^6.26.0",
+    "babel-preset-env": "^1.7.0",
+    "puppeteer": "^1.4.0"
+  }
+}

Diff for: tests/run.sh

@@ -29,12 +29,15 @@ if [ $COMPILE -eq 1 ]; then
     mkdir -p $JS_BUILD_DIR
     mkdir -p $C_BUILD_DIR
 
+    $SRC_DIR/generate-pre.sh
+
     echo -n "Compiling JavaScript tests... "
     for testfile in $JS_DIR/*.js; do
         testfile=$(basename $testfile)
         [ $testfile == "common.js" ] && continue
-        
+
         $SRC_DIR/emcc-cvmfs \
+            -s WASM=0 \
             --post-js $JS_DIR/common.js \
             --post-js $JS_DIR/$testfile \
             --shell-file $TEST_DIR/test_container.html \
@@ -49,6 +52,7 @@ if [ $COMPILE -eq 1 ]; then
         testfile=$(basename $testfile)
 
         $SRC_DIR/emcc-cvmfs \
+            -s WASM=0 \
             -s NO_EXIT_RUNTIME=0 \
             --shell-file $TEST_DIR/test_container.html \
             -o $C_BUILD_DIR/${testfile%*.*}.html \