Match ./configure --help parameter names with their defaults (#1120)

It is customary[^1] for "./configure --help" to use "--enable-foo"
spelling for default-disabled features and "--disable-foo" spelling for
default-enabled features. This custom allows admins to quickly discover
defaults without developers painstakingly documenting that default for
every parameter.

These changes are limited to "./configure --help" output. They do not
alter any defaults and do not alter non-help ./configure run outcomes.

[^1]: Example 1.1 at https://autotools.info/autoconf/arguments.html

diff --git a/configure.ac b/configure.ac
index bacb8ced3d286ccbe5c16cebe51019426d08d842..8e8815e89c9d9773cc784a9eb905c24b0fd1bffa 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -2388,8 +2388,8 @@ else
 fi
 
 AC_ARG_ENABLE(follow-x-forwarded-for,
-  AS_HELP_STRING([--enable-follow-x-forwarded-for],
-                 [Enable support for following the X-Forwarded-For
+  AS_HELP_STRING([--disable-follow-x-forwarded-for],
+                 [Do not follow the X-Forwarded-For
                  HTTP header to try to find the IP address of the
                  original or indirect client when a request has
                  been forwarded through other proxies.]), [
@@ -2428,8 +2428,8 @@ AC_SUBST(DEFAULT_HOSTS)
 
 # Select auth schemes modules to build
 AC_ARG_ENABLE(auth,
-  AS_HELP_STRING([--enable-auth],
-                 [Build global support for authentication. The list of schemes
+  AS_HELP_STRING([--disable-auth],
+                 [Do not support authentication. When supported, the list of schemes
                   and helpers to be enabled is defined elsewhere]), [
 SQUID_YESNO([$enableval],
             [unrecognized argument to --enable-auth: $enableval])
@@ -3428,7 +3428,7 @@ AC_MSG_NOTICE([Linux Netfilter Conntrack support enabled: ${with_netfilter_connt
 
 
 AC_ARG_ENABLE(zph-qos,
-  AS_HELP_STRING([--enable-zph-qos],[Enable ZPH QOS support]), [
+  AS_HELP_STRING([--disable-zph-qos],[Disable ZPH QOS support]), [
 SQUID_YESNO([$enableval],
             [unrecognized argument to --enable-zph-qos: $enableval])
 ])