apk: sanitize return value

Most applets return whatever apk_solver_commit() returns. It is the
number of errors found (or negative for hard error). Sanitize the
error value to not give false success exit code in the unlikely case
of errors % 256 == 0.

Reported-by: Max Justicz <max@justi.cz>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/apk.c b/src/apk.c
index 04b41d4..246e037 100644
--- a/src/apk.c
+++ b/src/apk.c
@@ -689,5 +689,7 @@ err:
 	apk_string_array_free(&args);
 	free(apk_argv);
 
+	if (r < 0) r = 250;
+	if (r > 99) r = 99;
 	return r;
 }