--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/leptonica/src/stack.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,70 @@
+/*====================================================================*
+ -  Copyright (C) 2001 Leptonica.  All rights reserved.
+ -
+ -  Redistribution and use in source and binary forms, with or without
+ -  modification, are permitted provided that the following conditions
+ -  are met:
+ -  1. Redistributions of source code must retain the above copyright
+ -     notice, this list of conditions and the following disclaimer.
+ -  2. Redistributions in binary form must reproduce the above
+ -     copyright notice, this list of conditions and the following
+ -     disclaimer in the documentation and/or other materials
+ -     provided with the distribution.
+ -
+ -  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ -  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ -  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ -  A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ANY
+ -  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ -  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ -  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ -  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ -  OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ -  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ -  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *====================================================================*/
+
+#ifndef  LEPTONICA_STACK_H
+#define  LEPTONICA_STACK_H
+
+/*!
+ * \file stack.h
+ *
+ * <pre>
+ *       Expandable pointer stack for arbitrary void* data.
+ *
+ *       The L_Stack is an array of void * ptrs, onto which arbitrary
+ *       objects can be stored.  At any time, the number of
+ *       stored objects is stack->n.  The object at the bottom
+ *       of the stack is at array[0]; the object at the top of
+ *       the stack is at array[n-1].  New objects are added
+ *       to the top of the stack, at the first available location,
+ *       which is array[n].  Objects are removed from the top of the
+ *       stack.  When an attempt is made to remove an object from an
+ *       empty stack, the result is null.   When the stack becomes
+ *       filled, so that n = nalloc, the size is doubled.
+ *
+ *       The auxiliary stack can be used to store and remove
+ *       objects for re-use.  It must be created by a separate
+ *       call to pstackCreate().  [Just imagine the chaos if
+ *       pstackCreate() created the auxiliary stack!]
+ *       pstackDestroy() checks for the auxiliary stack and removes it.
+ * </pre>
+ */
+
+
+    /*! Expandable pointer stack for arbitrary void* data.
+     * Note that array[n] is the first null ptr in the array
+     */
+struct L_Stack
+{
+    l_int32          nalloc;     /*!< size of ptr array              */
+    l_int32          n;          /*!< number of stored elements      */
+    void           **array;      /*!< ptr array                      */
+    struct L_Stack  *auxstack;   /*!< auxiliary stack                */
+};
+typedef struct L_Stack  L_STACK;
+
+
+#endif /*  LEPTONICA_STACK_H */
+