Fix crash on two-word expressions

cli/main.c

@@ -333,7 +333,12 @@ apply_modversion(pkgconf_client_t *client, pkgconf_pkg_t *world, void *data, int
 			pkgconf_dependency_t *dep = world_iter->data;
 			pkgconf_pkg_t *pkg = dep->match;
 
-			if (strcmp(pkg->why, queue_node->package))
+			const size_t name_len = strlen(pkg->why);
+			if (name_len > strlen(queue_node->package) ||
+			    strncmp(pkg->why, queue_node->package, name_len) ||
+			    (queue_node->package[name_len] != 0 &&
+			     !isspace(queue_node->package[name_len]) &&
+			     !PKGCONF_IS_OPERATOR_CHAR(queue_node->package[name_len])))
 				continue;
 
 			if (pkg->version != NULL) {
@@ -1400,6 +1405,15 @@ cleanup3:
 			pkgconf_queue_push(&pkgq, package);
 			pkg_optind++;
 		}
+		else if (argv[pkg_optind + 2] == NULL)
+		{
+			char packagebuf[PKGCONF_BUFSIZE];
+
+			snprintf(packagebuf, sizeof packagebuf, "%s %s", package, argv[pkg_optind + 1]);
+			pkg_optind += 2;
+
+			pkgconf_queue_push(&pkgq, packagebuf);
+		}
 		else
 		{
 			char packagebuf[PKGCONF_BUFSIZE];

tests/regress.sh

@@ -27,6 +27,9 @@ tests_init \
 	modversion_fullpath \
 	modversion_provides \
 	modversion_uninstalled \
+	modversion_one_word_expression \
+	modversion_two_word_expression \
+	modversion_three_word_expression \
 	pcpath \
 	virtual_variable \
 	fragment_collision \
@@ -301,3 +304,21 @@ modversion_uninstalled_body()
 	atf_check -o inline:"1.2.3\n" \
 		pkgconf --with-path="${selfdir}/lib1" --modversion omg
 }
+
+modversion_one_word_expression_body()
+{
+	atf_check -o inline:"1.2.3\n" \
+		pkgconf --with-path="${selfdir}/lib1" --modversion "foo > 1.0"
+}
+
+modversion_two_word_expression_body()
+{
+	atf_check -o inline:"1.2.3\n" \
+		pkgconf --with-path="${selfdir}/lib1" --modversion foo "> 1.0"
+}
+
+modversion_three_word_expression_body()
+{
+	atf_check -o inline:"1.2.3\n" \
+		pkgconf --with-path="${selfdir}/lib1" --modversion foo ">" 1.0
+}