freetdm: use m4_ifdef() to check for pkg-config macros and print a warning if they...

...instead of failing at runtime

Signed-off-by: Stefan Knoblich <s.knoblich@axsentis.de>

diff --git a/libs/freetdm/configure.ac b/libs/freetdm/configure.ac
index 8b878edc09c57cc4413f481360df8850c795416c..6b9287d791c15a233fb42cdaacd5105f1d4411e0 100644 (file)
--- a/libs/freetdm/configure.ac
+++ b/libs/freetdm/configure.ac
@@ -24,7 +24,12 @@ AC_PROG_MAKE_SET
 AM_PROG_CC_C_O
 AC_PROG_LIBTOOL
 AC_PROG_INSTALL
-PKG_PROG_PKG_CONFIG
+
+# NOTE: pkg-config is used to detect libisdn
+m4_ifdef([PKG_PROG_PKG_CONFIG],
+       [PKG_PROG_PKG_CONFIG],
+       [AC_MSG_WARN([pkg-config missing (required for libisdn detection)])]
+)
 
 AX_COMPILER_VENDOR
 
@@ -305,41 +310,44 @@ AC_ARG_WITH([libisdn],
 if test "${with_libisdn}" != "no"
 then
        AC_MSG_RESULT([${as_nl}<<>> ftmod_isdn (libisdn stack)])
-       PKG_CHECK_MODULES([libisdn],
-               [libisdn >= 0.0.1],
-               [AC_MSG_CHECKING([libisdn version])
-                LIBISDN_VERSION="`${PKG_CONFIG} --modversion libisdn`"
-                if test -z "${LIBISDN_VERSION}"; then
-                       AC_MSG_ERROR([Failed to retrieve libisdn version])
-                fi
-                AC_MSG_RESULT([${LIBISDN_VERSION}])
-
-                # check features
-                AC_MSG_CHECKING([for new experimental API])
-                AC_COMPILE_IFELSE(
-                       [AC_LANG_PROGRAM(
-                               [#include <libisdn/version.h>
-                                #if !LIBISDN_FEATURE(API2)
-                                #error "libisdn API v2 not available"
-                                #endif
-                               ],
-                               [;]
-                       )],
-                       [AC_MSG_RESULT([yes])],
-                       [AC_MSG_RESULT([no])]
+       m4_ifdef([PKG_CHECK_MODULES],
+               [PKG_CHECK_MODULES([libisdn],
+                       [libisdn >= 0.0.1],
+                       [AC_MSG_CHECKING([libisdn version])
+                        LIBISDN_VERSION="`${PKG_CONFIG} --modversion libisdn`"
+                        if test -z "${LIBISDN_VERSION}"; then
+                               AC_MSG_ERROR([Failed to retrieve libisdn version])
+                        fi
+                        AC_MSG_RESULT([${LIBISDN_VERSION}])
+
+                        # check features
+                        AC_MSG_CHECKING([for new experimental API])
+                        AC_COMPILE_IFELSE(
+                               [AC_LANG_PROGRAM(
+                                       [#include <libisdn/version.h>
+                                        #if !LIBISDN_FEATURE(API2)
+                                        #error "libisdn API v2 not available"
+                                        #endif
+                                       ],
+                                       [;]
+                               )],
+                               [AC_MSG_RESULT([yes])],
+                               [AC_MSG_RESULT([no])]
+                        )
+
+                        HAVE_LIBISDN="yes"
+                        AC_DEFINE([HAVE_LIBISDN], [1], [libisdn support])
+                        AC_SUBST([LIBISDN_CFLAGS],  [${libisdn_CFLAGS}])
+                        AC_SUBST([LIBISDN_CPPFLAGS],[${libisdn_CPPFLAGS}])
+                        AC_SUBST([LIBISDN_LDFLAGS], [${libisdn_LDFLAGS}])
+                        AC_SUBST([LIBISDN_LIBS],    [${libisdn_LIBS}])
+                        AC_SUBST([LIBISDN_VERSION])
+                       ],
+                       [AC_MSG_ERROR([Need libisdn-0.0.1 or higher])]
                 )
-
-                HAVE_LIBISDN="yes"
-                AC_DEFINE([HAVE_LIBISDN], [1], [libisdn support])
-                AC_SUBST([LIBISDN_CFLAGS],  [${libisdn_CFLAGS}])
-                AC_SUBST([LIBISDN_CPPFLAGS],[${libisdn_CPPFLAGS}])
-                AC_SUBST([LIBISDN_LDFLAGS], [${libisdn_LDFLAGS}])
-                AC_SUBST([LIBISDN_LIBS],    [${libisdn_LIBS}])
-                AC_SUBST([LIBISDN_VERSION])
-               ],
-               [AC_MSG_ERROR([Need libisdn-0.0.1 or higher])]
+                AX_LIB_PCAP],
+               [AC_MSG_WARN([pkg-config missing (required for libisdn detection)])]
        )
-       AX_LIB_PCAP
 fi
 AM_CONDITIONAL([HAVE_LIBISDN], [test "${HAVE_LIBISDN}" = "yes"])