Make ios-install-third-party.sh more robust

Summary:
See https://github.com/facebook/react-native/issues/14423

This adds checks after download that each file is present, and has the
correct sha1 hash.  If not, it will retry several times, and fail if
it can't successfully download the file.  If a file is downloaded, the
unpack and command will run, even if the third-party dir already
exists.  The diagnostics printed in the event of failure are improved.

This should be self-healing for anybody who has a bad ~/.rncache
directory.  The checksum will fail, and the files will be
redownloaded.

Reviewed By: hramos

Differential Revision: D5930707

fbshipit-source-id: cb15af949294243448ccc3995ec3f0396b1922b6

scripts/ios-install-third-party.sh

@@ -1,28 +1,56 @@
 #!/bin/bash
 
-set -e
-
 cachedir="$HOME/.rncache"
 mkdir -p "$cachedir"
 
+function file_fail () {
+    cachefile=$1
+    msg=$2
+
+    echo "$msg.  Debug info:" 2>&1
+    ls -l "$cachefile" 2>&1
+    shasum "$cachefile" 2>&1
+    exit 1
+}
+
 function fetch_and_unpack () {
     file=$1
     url=$2
-    cmd=$3
+    hash=$3
+    cmd=$4
 
-    if [ ! -f "$cachedir/$file" ]; then
+    retries=4
+    fetched=no
+
+    while true; do
+        if [ -f "$cachedir/$file" ]; then
+           if shasum -p "$cachedir/$file" |
+              awk -v hash="$hash" '{exit $1 != hash}'; then
+               break
+           else
+               echo "Incorrect hash:" 2>&1
+               shasum -p "$cachedir/$file" 2>&1
+               echo "Retrying..." 2>&1
+           fi
+        fi
+
+        (( retries = retries - 1 ))
+        if (( retries < 0 )); then
+            file_fail "$cachedir/$file" "Failed to successfully download '$file'"
+        fi
+
+        rm -f "$cachedir/$file"
         (cd "$cachedir"; curl -J -L -O "$url")
-    fi
+        fetched=yes
+    done
 
     dir=$(basename "$file" .tar.gz)
-    if [ ! -d "third-party/$dir" ]; then
+    if [ "$fetched" = "yes" ] || [ ! -d "third-party/$dir" ]; then
         (cd third-party;
+         rm -rf "$dir"
          echo Unpacking "$cachedir/$file"...
          if ! tar zxf "$cachedir/$file"; then
-             echo "Unpacking '$cachedir/$file' failed.  Debug info:" 2>&1
-             ls -l "$cachedir/$file" 2>&1
-             shasum ~/.rncache/boost_1_63_0.tar.gz 2>&1
-             exit 1
+             file_fail "$cachedir/$file" "Unpacking '$cachedir/$file' failed"
          fi
          cd "$dir"
          eval "${cmd:-true}")
@@ -33,7 +61,7 @@ mkdir -p third-party
 
 SCRIPTDIR=$(dirname "$0")
 
-fetch_and_unpack glog-0.3.4.tar.gz https://github.com/google/glog/archive/v0.3.4.tar.gz "\"$SCRIPTDIR/ios-configure-glog.sh\""
-fetch_and_unpack double-conversion-1.1.5.tar.gz https://github.com/google/double-conversion/archive/v1.1.5.tar.gz
-fetch_and_unpack boost_1_63_0.tar.gz https://github.com/react-native-community/boost-for-react-native/releases/download/v1.63.0-0/boost_1_63_0.tar.gz
-fetch_and_unpack folly-2016.09.26.00.tar.gz https://github.com/facebook/folly/archive/v2016.09.26.00.tar.gz
+fetch_and_unpack glog-0.3.4.tar.gz https://github.com/google/glog/archive/v0.3.4.tar.gz 69f91cd5a1de35ead0bc4103ea87294b0206a456 "\"$SCRIPTDIR/ios-configure-glog.sh\""
+fetch_and_unpack double-conversion-1.1.5.tar.gz https://github.com/google/double-conversion/archive/v1.1.5.tar.gz 96a8aba1b4ce7d4a7a3c123be26c379c2fed1def
+fetch_and_unpack boost_1_63_0.tar.gz https://github.com/react-native-community/boost-for-react-native/releases/download/v1.63.0-0/boost_1_63_0.tar.gz c3f57e1d22a995e608983effbb752b54b6eab741
+fetch_and_unpack folly-2016.09.26.00.tar.gz https://github.com/facebook/folly/archive/v2016.09.26.00.tar.gz f3b928b5039235bad6cece638c597c6684d1e4e6