+ /*
+ * If the *broken block (Z) is already broken and we
+ * encounter its breaker (B), make the tok block (A)
+ * pending on that inner breaker (B).
+ * Graphically, [A breaker=[B! broken=[Z->B B] tok=A] Z]
+ * becomes breaker=[A broken=[B! [Z->B B] tok=A] Z]
+ * and finally [A! [B!->A [Z->B B] A] Z].
+ * In these graphics, "->" indicates the "pending"
+ * pointer and "!" indicates the MDOC_BREAK flag.
+ * Each of the cases gets one additional pointer (B->A)
+ * and one additional flag (A!).
+ */
+ if (breaker == broken->pending) {
+ broken = breaker;
+ continue;
+ }
+
+ if (REWIND_THIS != rew_dohalt(tok, MDOC_BLOCK, breaker))
+ continue;
+ if (MDOC_BODY == broken->type)
+ broken = broken->parent;
+
+ /*
+ * Found the breaker.
+ * If another, outer breaker (X) is already pending on
+ * the *broken block (B), we must not clobber the link
+ * to the outer breaker, but make it pending on the
+ * new, now inner breaker (A).
+ * Graphically, [X! breaker=[A broken=[B->X X] tok=A] B]
+ * becomes [X! breaker=[A->X broken=[B X] tok=A] B]
+ * and finally [X! [A!->X [B->A X] A] B].
+ */
+ if (broken->pending) {
+ struct mdoc_node *taker;
+
+ /*
+ * If the inner breaker (A) is already broken,
+ * too, it cannot take on the outer breaker (X)
+ * but must hand it on to its own breakers (Y):
+ * [X! [Y! breaker=[A->Y Y] broken=[B->X X] tok=A] B]
+ * [X! take=[Y!->X brea=[A->Y Y] brok=[B X] tok=A] B]
+ * and finally [X! [Y!->X [A!->Y Y] [B->A X] A] B].
+ */
+ taker = breaker;
+ while (taker->pending)
+ taker = taker->pending;
+ taker->pending = broken->pending;
+ }
git.ckatri.com / mandoc.git / blobdiff