lib: add frr_version_cmp()

This just compares 2 version strings.

Signed-off-by: David Lamparter <equinox@diac24.net>

4 files changed, 101 insertions, 1 deletions

diff --git a/lib/defaults.c b/lib/defaults.c
new file mode 100644
index 000000000..cfc8fa27f
--- /dev/null
+++ b/lib/defaults.c
@@ -0,0 +1,75 @@
+/*
+ * FRR switchable defaults.
+ * Copyright (c) 2017-2019  David Lamparter, for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <zebra.h>
+
+#include "defaults.h"
+#include "libfrr.h"
+#include "version.h"
+
+static int version_value(int ch)
+{
+	/* non-ASCII shouldn't happen */
+	if (ch < 0 || ch >= 128)
+		return 2;
+
+	/* ~foo sorts older than nothing */
+	if (ch == '~')
+		return 0;
+	if (ch == '\0')
+		return 1;
+	if (isalpha(ch))
+		return 0x100 + tolower(ch);
+
+	/* punctuation and digits (and everything else) */
+	return 0x200 + ch;
+}
+
+int frr_version_cmp(const char *aa, const char *bb)
+{
+	const char *apos = aa, *bpos = bb;
+
+	/* || is correct, we won't scan past the end of a string since that
+	 * doesn't compare equal to anything else */
+	while (apos[0] || bpos[0]) {
+		if (isdigit((unsigned char)apos[0]) &&
+		    isdigit((unsigned char)bpos[0])) {
+			unsigned long av, bv;
+			char *aend = NULL, *bend = NULL;
+
+			av = strtoul(apos, &aend, 10);
+			bv = strtoul(bpos, &bend, 10);
+			if (av < bv)
+				return -1;
+			if (av > bv)
+				return 1;
+
+			apos = aend;
+			bpos = bend;
+			continue;
+		}
+
+		int a = version_value(*apos++);
+		int b = version_value(*bpos++);
+
+		if (a < b)
+			return -1;
+		if (a > b)
+			return 1;
+	}
+	return 0;
+}
diff --git a/lib/defaults.h b/lib/defaults.h
new file mode 100644
index 000000000..c21534150
--- /dev/null
+++ b/lib/defaults.h
@@ -0,0 +1,24 @@
+/*
+ * FRR switchable defaults.
+ * Copyright (C) 2017-2019  David Lamparter for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _FRR_DEFAULTS_H
+#define _FRR_DEFAULTS_H
+
+/* like strcmp(), but with version ordering */
+extern int frr_version_cmp(const char *aa, const char *bb);
+
+#endif /* _FRR_DEFAULTS_H */
diff --git a/lib/libfrr.c b/lib/libfrr.c
index 5f292c989..1dd7e932c 100644
--- a/lib/libfrr.c
+++ b/lib/libfrr.c
@@ -175,7 +175,6 @@ static const struct optspec os_user = {"u:g:",
 				       "  -g, --group        Group to run as\n",
 				       lo_user};
 
-
 bool frr_zclient_addr(struct sockaddr_storage *sa, socklen_t *sa_len,
 		      const char *path)
 {
diff --git a/lib/subdir.am b/lib/subdir.am
index be059c894..cb6fa7a3b 100644
--- a/lib/subdir.am
+++ b/lib/subdir.am
@@ -18,6 +18,7 @@ lib_libfrr_la_SOURCES = \
 	lib/command_parse.y \
 	lib/csv.c \
 	lib/debug.c \
+	lib/defaults.c \
 	lib/distribute.c \
 	lib/ferr.c \
 	lib/filter.c \
@@ -157,6 +158,7 @@ pkginclude_HEADERS += \
 	lib/csv.h \
 	lib/db.h \
 	lib/debug.h \
+	lib/defaults.h \
 	lib/distribute.h \
 	lib/ferr.h \
 	lib/filter.h \