detect native libotr during installation

build.sh

@@ -0,0 +1,23 @@
+#!/bin/bash
+export otr_version=`./check-otr-version.sh`
+
+if [ "${otr_version}" == '' ]
+then
+    echo "No libotr found on the system."
+    echo "On Debian/Ubuntu you can install it with the following command:"
+    echo "sudo apt-get install libotr2 libotr2-dev"
+    exit
+fi
+
+echo "Found local version of libotr: ${otr_version}"
+
+if [ "${otr_version}" == '3' ]
+then
+    make module
+fi
+
+if [ "${otr_version}" == '4' ]
+then
+    echo "module 'otr3' requires native libotr 3.2.1 on the system."
+fi
+

check-otr-version.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# use the C pre-processor to get the version of libotr on the system
+
+cat >tmp.h <<EOF
+ #include <libotr/version.h>
+ #ifdef OTRL_VERSION_MAJOR
+    otrl-version OTRL_VERSION_MAJOR OTRL_VERSION_MINOR OTRL_VERSION_SUB
+ #else
+    otrl-version 0 0 0
+ #endif
+EOF
+
+if [ -e tmp.h ]
+then
+ #prints the major version or 0 if libotr dev headers not found
+ cc -E tmp.h 2>/dev/null | grep "otrl-version" | awk '{print $2}'
+ rm tmp.h
+fi

package.json

@@ -13,6 +13,6 @@
         "url":"git@github.com:mnaamani/node-otr-v2.git"
     },
     "scripts":{
-        "preinstall":"make module"
+        "preinstall":"./build.sh"
     }
 }