Add checks for required packages

bootstrap

@@ -1,5 +1,50 @@
 #!/bin/sh
 
+DIE=0
+
+(autoconf --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: You must have \`autoconf' installed to."
+  echo "Download the appropriate package for your distribution,"
+  echo "or get the source tarball at ftp://ftp.gnu.org/pub/gnu/"
+  DIE=1
+}
+
+(libtool --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: You must have \`libtool' installed."
+  echo "Get ftp://ftp.gnu.org/pub/gnu/libtool-1.2d.tar.gz"
+  echo "(or a newer version if it is available)"
+  DIE=1
+}
+
+(automake --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: You must have \`automake' installed."
+  echo "Get ftp://ftp.gnu.org/pub/gnu/automake-1.3.tar.gz"
+  echo "(or a newer version if it is available)"
+  DIE=1
+}
+
+(aclocal --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: Missing \`aclocal'.  The version of \`automake'"
+  echo "installed doesn't appear recent enough."
+  echo "Get ftp://ftp.gnu.org/pub/gnu/automake-1.3.tar.gz"
+  echo "(or a newer version if it is available)"
+  DIE=1
+}
+
+(pkg-config --version) < /dev/null > /dev/null 2>&1 || {
+  echo
+  echo "**Error**: You must have \`pkg-config' installed."
+  DIE=1
+}
+
+if test "$DIE" -eq 1; then
+  exit 1
+fi
+
 set -x
 
 rm -rf autom4te*.cache