configure: Properly fail if bison or flex is missing

If bison or flex is missing, and are needed, fail configure.
jonmoesli · Jun 29, 2020 · dd87051 · dd87051
1 parent 9a6e303
commit dd87051
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/configure.ac b/configure.ac
@@ -297,8 +297,14 @@ AC_ISC_POSIX
 AC_PROG_CC
 AC_PROG_CPP
 AC_PROG_CXX # lucene plugin needs this
-AC_CHECK_TOOL([FLEX],[flex],AC_ERROR(flex is required))
-AC_CHECK_TOOL([BISON],[bison],AC_ERROR(bison is required))
+AC_CHECK_TOOL([FLEX],[flex],[:])
+AC_CHECK_TOOL([BISON],[bison],[:])
+AS_IF([test "$BISON" = ":" && test ! -e src/lib/event-filter-parser.h],
+  AC_MSG_ERROR([Bison is required when building from git])
+])
+AS_IF([test "$FLEX" = ":" && test ! -e src/lib/event-filter-lexer.c],
+  AC_MSG_ERROR([flex is required when building from git])
+])
 AC_HEADER_STDC
 AC_C_INLINE
 AC_PROG_LIBTOOL