From f8638cdb6878a713e4bc56b542c7dbfdaed26e7c Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Tue, 26 Jul 2011 12:17:45 -0500
Subject: [PATCH] pkg: add pkg_verify_dependency()

---
 pkg.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 50 insertions(+), 1 deletion(-)

diff --git a/pkg.c b/pkg.c
index ed73b14..82ec209 100644
--- a/pkg.c
+++ b/pkg.c
@@ -142,6 +142,55 @@ pkg_compare_version(const char *a, const char *b)
 	return 1;
 }
 
+/*
+ * pkg_verify_dependency(pkgdep)
+ *
+ * verify a pkg_dependency_t node in the depgraph.  if the dependency is solvable,
+ * return the appropriate pkg_t object, else NULL.
+ */
+pkg_t *
+pkg_verify_dependency(pkg_dependency_t *pkgdep)
+{
+	pkg_t *pkg;
+
+	pkg = pkg_find(pkgdep->package);
+	if (pkg == NULL)
+		return NULL;
+
+	switch(pkgdep->compare)
+	{
+	case PKG_LESS_THAN:
+		if (pkg_compare_version(pkgdep->version, pkg->version) < 0)
+			return pkg;
+		break;
+	case PKG_GREATER_THAN:
+		if (pkg_compare_version(pkgdep->version, pkg->version) > 0)
+			return pkg;
+		break;
+	case PKG_LESS_THAN_EQUAL:
+		if (pkg_compare_version(pkgdep->version, pkg->version) <= 0)
+			return pkg;
+		break;
+	case PKG_GREATER_THAN_EQUAL:
+		if (pkg_compare_version(pkgdep->version, pkg->version) >= 0)
+			return pkg;
+		break;
+	case PKG_EQUAL:
+		if (pkg_compare_version(pkgdep->version, pkg->version) == 0)
+			return pkg;
+		break;
+	case PKG_NOT_EQUAL:
+		if (pkg_compare_version(pkgdep->version, pkg->version) != 0)
+			return pkg;
+		break;
+	case PKG_ANY:
+	default:
+		return pkg;
+	}
+
+	return NULL;
+}
+
 /*
  * pkg_verify_graph(root, depth)
  *
@@ -172,7 +221,7 @@ pkg_traverse(pkg_t *root,
 		if (*node->package == '\0')
 			continue;
 
-		pkgdep = pkg_find(node->package);
+		pkgdep = pkg_verify_dependency(node);
 		if (pkgdep == NULL)	
 		{
 			fprintf(stderr, "Package %s was not found in the pkg-config search path.\n", node->package);