1 files changed, 55 insertions, 0 deletions
diff --git a/common/m4/gst-parser.m4 b/common/m4/gst-parser.m4
new file mode 100644
index 0000000..b002047
--- /dev/null
+++ b/common/m4/gst-parser.m4
@@ -0,0 +1,55 @@
+AC_DEFUN([AG_GST_BISON_CHECK],
+[
+  dnl FIXME: check if AC_PROG_YACC is suitable here
+  dnl FIXME: make precious
+  AC_PATH_PROG(BISON_PATH, bison, no)
+  if test x$BISON_PATH = xno; then
+    AC_MSG_ERROR(Could not find bison)
+  fi
+
+  dnl check bison version
+  dnl we need version >= 2.4 for the '<>' support
+  dnl in the parser.
+  dnl First lines observed: 'bison (GNU Bison) 2.3' or 'GNU Bison version 1.28'
+  bison_min_version=2.4
+  bison_version=`$BISON_PATH --version | head -n 1 |  sed 's/^[[^0-9]]*//' | sed 's/[[^0-9]]*$//' | cut -d' ' -f1`
+  AC_MSG_CHECKING([bison version $bison_version >= $bison_min_version])
+
+  if perl -we "exit ((v$bison_version ge v$bison_min_version) ? 0 : 1)"; then
+    AC_MSG_RESULT([yes])
+  else
+    AC_MSG_ERROR([no])
+  fi
+])
+
+AC_DEFUN([AG_GST_FLEX_CHECK],
+[
+  dnl we require flex for building the parser
+  AC_PATH_PROG(FLEX_PATH, flex, no)
+  if test x$FLEX_PATH = xno; then
+    AC_MSG_ERROR(Could not find flex)
+  fi
+
+  dnl check flex version
+  dnl we need version >= 2.5.31 for the reentrancy support
+  dnl in the parser.
+  flex_min_version=2.5.31
+  flex_version=`$FLEX_PATH --version | head -n 1 | awk '{print $2}'`
+  AC_MSG_CHECKING([flex version $flex_version >= $flex_min_version])
+  if perl -w <<EOF
+    (\$min_version_major, \$min_version_minor, \$min_version_micro ) = "$flex_min_version" =~ /(\d+)\.(\d+)\.(\d+)/;
+    (\$flex_version_major, \$flex_version_minor, \$flex_version_micro ) = "$flex_version" =~ /(\d+)\.(\d+)\.(\d+)/;
+    exit (((\$flex_version_major > \$min_version_major) ||
+     ((\$flex_version_major == \$min_version_major) &&
+      (\$flex_version_minor > \$min_version_minor)) ||
+     ((\$flex_version_major == \$min_version_major) &&
+      (\$flex_version_minor == \$min_version_minor) &&
+      (\$flex_version_micro >= \$min_version_micro)))
+     ? 0 : 1);
+EOF
+  then
+    AC_MSG_RESULT(yes)
+  else
+    AC_MSG_ERROR([no])
+  fi
+])