initial raytracing experiment

[dosdemo] / src / darray.h

diff --git a/src/darray.h b/src/darray.h
new file mode 100644 (file)
index 0000000..b9a7051
--- /dev/null
+++ b/src/darray.h
@@ -0,0 +1,48 @@
+#ifndef DYNAMIC_ARRAY_H_
+#define DYNAMIC_ARRAY_H_
+
+void *darr_alloc(int elem, int szelem);
+void darr_free(void *da);
+void *darr_resize_impl(void *da, int elem);
+#define darr_resize(da, elem)  do { (da) = darr_resize_impl(da, elem); } while(0)
+
+int darr_empty(void *da);
+int darr_size(void *da);
+
+void *darr_clear_impl(void *da);
+#define darr_clear(da)                 do { (da) = darr_clear_impl(da); } while(0)
+
+/* stack semantics */
+void *darr_push_impl(void *da, void *item);
+#define darr_push(da, item)            do { (da) = darr_push_impl(da, item); } while(0)
+void *darr_pop_impl(void *da);
+#define darr_pop(da)                   do { (da) = darr_pop_impl(da); } while(0)
+
+/* Finalize the array. No more resizing is possible after this call.
+ * Use free() instead of dynarr_free() to deallocate a finalized array.
+ * Returns pointer to the finalized array.
+ * Complexity: O(n)
+ */
+void *darr_finalize(void *da);
+
+/* utility macros to push characters to a string. assumes and maintains
+ * the invariant that the last element is always a zero
+ */
+#define darr_strpush(da, c) \
+       do { \
+               char cnull = 0, ch = (char)(c); \
+               (da) = dynarr_pop_impl(da); \
+               (da) = dynarr_push_impl((da), &ch); \
+               (da) = dynarr_push_impl((da), &cnull); \
+       } while(0)
+
+#define darr_strpop(da) \
+       do { \
+               char cnull = 0; \
+               (da) = dynarr_pop_impl(da); \
+               (da) = dynarr_pop_impl(da); \
+               (da) = dynarr_push_impl((da), &cnull); \
+       } while(0)
+
+
+#endif /* DYNAMIC_ARRAY_H_ */