allow for empty write buffers

diff --git a/src/lib/bio/mem.c b/src/lib/bio/mem.c
index 78d93ae9233a4cf3d63854eef8db8b8409d76421..f626ee553ad30ea3e7057842df55a861afb96bc2 100644 (file)
--- a/src/lib/bio/mem.c
+++ b/src/lib/bio/mem.c
@@ -672,13 +672,18 @@ fr_bio_t *fr_bio_mem_alloc(TALLOC_CTX *ctx, size_t read_size, size_t write_size,
        /*
         *      The caller has to state that the API is caching data both ways.
         */
-       if (!read_size || !write_size) return NULL;
+       if (!read_size) return NULL;
 
        if (!fr_bio_mem_buf_alloc(my, &my->read_buffer, read_size)) return NULL;
-       if (!fr_bio_mem_buf_alloc(my, &my->write_buffer, write_size)) return NULL;
-
        my->bio.read = fr_bio_mem_read;
-       my->bio.write = fr_bio_mem_write_next;
+
+       if (write_size) {
+               if (!fr_bio_mem_buf_alloc(my, &my->write_buffer, write_size)) return NULL;
+
+               my->bio.write = fr_bio_mem_write_next;
+       } else {
+               my->bio.write = fr_bio_next_write;
+       }
 
        fr_bio_chain(&my->bio, next);