configure: update zscanner configuration

README

@@ -11,17 +11,10 @@ Knot DNS has several dependencies:
 
 Optional packages:
 * libcap-ng >= 0.6.4 (for POSIX 1003.1e capabilites(7))
-* ragel (for fast zone parsing)
 
 Dependencies for building documentation:
 * texinfo
 
-By default Knot DNS is distributed with a slower zone file parser because of
-smaller source file and quick compile time. In most cases it is sufficient.
-If you plan to process large zone files, we recommend to build Knot DNS
-using ./configure --enable-fastparser. In this case Ragel compiler is required
-and it is normal if the C compiler takes much more time (minutes).
-
 Installation
 ============
 
@@ -45,7 +38,6 @@ $ sudo apt-get install git-core libtool autoconf flex bison libssl-dev liburcu-d
 
 Install optional packages:
 ($ sudo apt-get install libcap-ng-dev)
-($ sudo apt-get install ragel)
 
 If the liburcu-dev package is not present, install it from the source code
 (http://lttng.org/urcu)
@@ -63,7 +55,6 @@ $ yum install libtool autoconf flex bison openssl-devel userspace-rcu-devel
 
 Install optional packages:
 ($ yum install libcap-ng-devel)
-($ yum install ragel)
 
 OS X
 ----

configure.ac

@@ -70,7 +70,7 @@ AM_CONDITIONAL([HAVE_RAGEL], test "$RAGEL" != "true")
 
 # Set FSM type for Ragel
 AC_ARG_ENABLE([fastparser],
-    AS_HELP_STRING([--disable-fastparser], [Don't generate fast zone parser (requires Ragel!)]),
+    AS_HELP_STRING([--disable-fastparser], [Don't use faster zone parser]),
     [],
     [enable_fastparser=yes])
 

doc/installation.texi

@@ -27,8 +27,6 @@ autoconf >= 2.65
 flex >= 2.5.31
 @item
 bison >= 2.3
-@item
-ragel >= 6.7 (only required for fast zone parsing)
 @end itemize
 
 @node Required libraries
@@ -115,10 +113,6 @@ $ ./configure --help
 If you have trouble with unknown syscalls under valgrind, disable recvmmsg by
 adding a parameter @command{--enable-recvmmsg=no} to configure.
 
-If you want to load huge zone files quickly, enable fast zone parser by
-adding a parameter @command{--enable-fastparser} to configure. In this case
-Ragel compiler is required.
-
 Knot DNS has also support for link time optimizations.
 You can enable it by the configure parameter @command{./configure --enable-lto=yes}.
 It is however disabled by default as it is known to be broken in some compiler