Add support for dpkg-style sorting of tilde in version/release

- This allows much nicer handling some common scenarios such as
  upstream pre-releases where the pre-release version would normally
  appear newer than final release, eg 1.0-rc1 vs 1.0. Previously this
  required mapping the pre-release tag into the release tag to achieve
  desired sorting, with tild this becomes simply 1.0~rc1 < 1.0.
- Add a rpmlib() tracking dependency to prevent older rpm versions
  from getting confused with packages relying on the new behavior.

Signed-off-by: Panu Matilainen <pmatilai@redhat.com>

1 files changed, 12 insertions, 3 deletions

diff --git a/lib/rpmvercmp.c b/lib/rpmvercmp.c
index f5ae09290..a6b707583 100644
--- a/lib/rpmvercmp.c
+++ b/lib/rpmvercmp.c
@@ -32,9 +32,18 @@ int rpmvercmp(const char * a, const char * b)
     two = str2;
 
     /* loop through each version segment of str1 and str2 and compare them */
-    while (*one && *two) {
-	while (*one && !risalnum(*one)) one++;
-	while (*two && !risalnum(*two)) two++;
+    while (*one || *two) {
+	while (*one && !risalnum(*one) && *one != '~') one++;
+	while (*two && !risalnum(*two) && *two != '~') two++;
+
+	/* handle the tilde separator, it sorts before everthing else */
+	if (*one == '~' || *two == '~') {
+	    if (*one != '~') return 1;
+	    if (*two != '~') return -1;
+	    one++;
+	    two++;
+	    continue;
+	}
 
 	/* If we ran to the end of either, we are finished with the loop */
 	if (!(*one && *two)) break;