iosbuild.sh: sync some aspects of xcframeworkbuild.sh

Change-Id: Ie29f986767132fe980d71e43f6b8d367a9e2e6a9
diff --git a/iosbuild.sh b/iosbuild.sh
index e4031de..044745f 100755
--- a/iosbuild.sh
+++ b/iosbuild.sh
@@ -1,8 +1,9 @@
 #!/bin/bash
 #
-# This script generates 'WebP.framework' and 'WebPDecoder.framework'. An iOS
-# app can decode WebP images by including 'WebPDecoder.framework' and both
-# encode and decode WebP images by including 'WebP.framework'.
+# This script generates 'WebP.framework' and 'WebPDecoder.framework',
+# 'WebPDemux.framework' and 'WebPMux.framework'.
+# An iOS app can decode WebP images by including 'WebPDecoder.framework' and
+# both encode and decode WebP images by including 'WebP.framework'.
 #
 # Run ./iosbuild.sh to generate the frameworks under the current directory
 # (the previous build will be erased if it exists).
@@ -50,13 +51,27 @@
   exit 1
 elif [[ ${SDK%%.*} -gt 8 ]]; then
   EXTRA_CFLAGS="-fembed-bitcode"
-elif [[ ${SDK} < 6.0 ]]; then
+elif [[ ${SDK%%.*} -le 6 ]]; then
   echo "You need iOS SDK version 6.0 or above"
   exit 1
-else
-  echo "iOS SDK Version ${SDK}"
 fi
 
+echo "Xcode Version: ${XCODE}"
+echo "iOS SDK Version: ${SDK}"
+
+if [[ -e "${BUILDDIR}" || -e "${TARGETDIR}" || -e "${DECTARGETDIR}" \
+      || -e "${MUXTARGETDIR}" || -e "${DEMUXTARGETDIR}" ]]; then
+  cat << EOF
+WARNING: The following directories will be deleted:
+WARNING:   ${BUILDDIR}
+WARNING:   ${TARGETDIR}
+WARNING:   ${DECTARGETDIR}
+WARNING:   ${MUXTARGETDIR}
+WARNING:   ${DEMUXTARGETDIR}
+WARNING: The build will continue in 5 seconds...
+EOF
+  sleep 5
+fi
 rm -rf ${BUILDDIR} ${TARGETDIR} ${DECTARGETDIR} \
     ${MUXTARGETDIR} ${DEMUXTARGETDIR}
 mkdir -p ${BUILDDIR} ${TARGETDIR}/Headers/ ${DECTARGETDIR}/Headers/ \
@@ -64,12 +79,12 @@
 
 if [[ ! -e ${SRCDIR}/configure ]]; then
   if ! (cd ${SRCDIR} && sh autogen.sh); then
-    cat <<EOT
+    cat << EOF
 Error creating configure script!
 This script requires the autoconf/automake and libtool to build. MacPorts can
 be used to obtain these:
 http://www.macports.org/install.php
-EOT
+EOF
     exit 1
   fi
 fi
@@ -148,3 +163,5 @@
 cp -a ${SRCDIR}/src/webp/{decode,types,mux_types,demux}.h \
     ${DEMUXTARGETDIR}/Headers/
 ${LIPO} -create ${DEMUXLIBLIST} -output ${DEMUXTARGETDIR}/WebPDemux
+
+echo  "SUCCESS"