build: remove --enable-upnp-default from configure

Author: fanquake

configure.ac

@@ -163,12 +163,6 @@ AC_ARG_WITH([miniupnpc],
   [use_upnp=$withval],
   [use_upnp=auto])
 
-AC_ARG_ENABLE([upnp-default],
-  [AS_HELP_STRING([--enable-upnp-default],
-  [if UPNP is enabled, turn it on at startup (default is no)])],
-  [use_upnp_default=$enableval],
-  [use_upnp_default=no])
-
 AC_ARG_WITH([natpmp],
             [AS_HELP_STRING([--with-natpmp],
                             [enable NAT-PMP (default is yes if libnatpmp is found)])],
@@ -1759,15 +1753,8 @@ if test "$have_miniupnpc" = "no"; then
 else
   if test "$use_upnp" != "no"; then
     AC_MSG_RESULT([yes])
-    AC_MSG_CHECKING([whether to build with UPnP enabled by default])
     use_upnp=yes
-    upnp_setting=0
-    if test "$use_upnp_default" != "no"; then
-      use_upnp_default=yes
-      upnp_setting=1
-    fi
-    AC_MSG_RESULT([$use_upnp_default])
-    AC_DEFINE_UNQUOTED([USE_UPNP],[$upnp_setting],[UPnP support not compiled if undefined, otherwise value (0 or 1) determines default state])
+    AC_DEFINE([USE_UPNP], [1], [Define to 1 if UPnP support should be compiled in.])
     if test "$TARGET_OS" = "windows"; then
       MINIUPNPC_CPPFLAGS="$MINIUPNPC_CPPFLAGS -DSTATICLIB -DMINIUPNP_STATICLIB"
     fi

doc/build-unix.md

@@ -72,7 +72,7 @@ executables, which are based on BerkeleyDB 4.8. If you do not care about wallet
 
 To build Bitcoin Core without wallet, see [*Disable-wallet mode*](#disable-wallet-mode)
 
-Optional port mapping libraries (see: `--with-miniupnpc`, `--enable-upnp-default`, and `--with-natpmp`):
+Optional port mapping libraries (see: `--with-miniupnpc` and `--with-natpmp`):
 
     sudo apt install libminiupnpc-dev libnatpmp-dev
 
@@ -133,7 +133,7 @@ pass `--with-incompatible-bdb` to configure. Otherwise, you can build Berkeley D
 
 To build Bitcoin Core without wallet, see [*Disable-wallet mode*](#disable-wallet-mode)
 
-Optional port mapping libraries (see: `--with-miniupnpc`, `--enable-upnp-default`, and `--with-natpmp`):
+Optional port mapping libraries (see: `--with-miniupnpc` and `--with-natpmp`):
 
     sudo dnf install miniupnpc-devel libnatpmp-devel
 
@@ -176,11 +176,7 @@ miniupnpc
 
 [miniupnpc](https://miniupnp.tuxfamily.org) may be used for UPnP port mapping.  It can be downloaded from [here](
 https://miniupnp.tuxfamily.org/files/).  UPnP support is compiled in and
-turned off by default.  See the configure options for UPnP behavior desired:
-
-    --without-miniupnpc      No UPnP support, miniupnp not required
-    --disable-upnp-default   (the default) UPnP support turned off by default at runtime
-    --enable-upnp-default    UPnP support turned on by default at runtime
+turned off by default.
 
 libnatpmp
 ---------