correct logic in alloc_reserve function

diff --git a/src/lib/io/message.c b/src/lib/io/message.c
index ca4e2a9fe122c410d341994e987436ed602367d2..64c56c21e8588cd6fcd87774974934c4e64a123f 100644 (file)
--- a/src/lib/io/message.c
+++ b/src/lib/io/message.c
@@ -1076,9 +1076,10 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
                                       size_t reserve_size)
 {
        bool cleaned_up;
-       size_t room;
+       size_t data_size;
        uint8_t *p;
        fr_message_t *m2;
+       size_t m_rb_size;
 
        (void) talloc_get_type_abort(ms, fr_message_set_t);
 
@@ -1087,7 +1088,6 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
        rad_assert(m->status == FR_MESSAGE_USED);
        rad_assert(m->rb != NULL);
        rad_assert(m->data != NULL);
-       rad_assert(m->data_size == 0);
        rad_assert(m->rb_size >= actual_packet_size);
 
        p = fr_ring_buffer_alloc(m->rb, actual_packet_size);
@@ -1099,7 +1099,8 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
 
        rad_assert(p == m->data);
 
-       room = m->rb_size - actual_packet_size;
+       m_rb_size = m->rb_size; /* for ring buffer cleanups */
+       data_size = m->rb_size - actual_packet_size;
 
        /*
         *      The caller can change m->data size to something a bit
@@ -1112,7 +1113,7 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
         *      If we've allocated all of the reserved ring buffer
         *      data, then just reserve a brand new reservation.
         */
-       if (!room) return fr_message_reserve(ms, reserve_size);
+       if (!data_size) return fr_message_reserve(ms, reserve_size);
 
        /*
         *      Allocate a new message.
@@ -1121,34 +1122,26 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
        if (!m2) return NULL;
 
        /*
-        *      Mark how much room there is in this message.
+        *      Track how much data there is in the packet.
         */
        m2->rb = m->rb;
-       m2->data_size = 0;
-       m2->rb_size = room;
+       m2->data_size = data_size;
+       m2->rb_size = reserve_size;
 
        /*
-        *      There is more room than the asked reservation.  The
-        *      reservation MUST succeed.
+        *      Try to extend the reservation.  If we can do it,
+        *      return.
         */
-       if (room >= reserve_size) {
-               m2->data = fr_ring_buffer_reserve(m2->rb, m2->rb_size);
-               rad_assert(m2->data != NULL);
-               if (!m2->data) {
-                       fr_strerror_printf("Failed reserving from ring buffer: %s", fr_strerror());
-                       m->rb = NULL;
-                       m->status = FR_MESSAGE_DONE;
-                       return NULL;
-               }
-       }
+       m2->data = fr_ring_buffer_reserve(m2->rb, m2->rb_size);
+       if (m2->data) return m2;
 
        /*
-        *      The caller is asking for more reserve than we have
-        *      room for.  Find a new ring buffer, and call
-        *      fr_ring_buffer_reserve_split() on it, and on the old
-        *      one.
+        *      Reserve data from a new ring buffer.  If it doesn't
+        *      succeed, ensure that the old message will properly
+        *      clean up the old ring buffer.
         */
        if (!fr_message_get_ring_buffer(ms, m2, false)) {
+               m->rb_size = m_rb_size;
                return NULL;
        }
 
@@ -1162,9 +1155,12 @@ fr_message_t *fr_message_alloc_reserve(fr_message_set_t *ms, fr_message_t *m, si
        }
 
        /*
-        *      Copy the remaining data from the old buffer to the new one.
+        *      Copy the remaining data from the old buffer to the new
+        *      one.  And ensure that the old message will properly
+        *      clean up the ring buffer.
         */
-       memcpy(m2->data, m->data + actual_packet_size, room);
+       memcpy(m2->data, m->data + actual_packet_size, data_size);
+       m->rb_size = m_rb_size;
        return m2;
 }