1 files changed, 60 insertions, 0 deletions
diff --git a/lib/cbit/cqueue.h b/lib/cbit/cqueue.h
new file mode 100644
index 0000000..0ab5488
--- /dev/null
+++ b/lib/cbit/cqueue.h
@@ -0,0 +1,60 @@
+#pragma once
+#include "misc.h"
+
+struct cqueue_internal {
+    char *start, *end, *read_ptr, *write_ptr;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void cqueue_realloc_internal(struct cqueue_internal *ci,
+                             size_t new_capacity_bytes);
+#ifdef __cplusplus
+}
+#endif
+
+#define DECL_CQUEUE(ty, name) \
+    typedef ty __CQUEUE_TY_##name; \
+    struct cqueue_##name { \
+        union { \
+            struct cqueue_internal ci; \
+            struct { \
+                __CQUEUE_TY_##name *start, *end, *read_ptr, *write_ptr; \
+            }; \
+        }; \
+    }; \
+    UNUSED_STATIC_INLINE \
+    void cqueue_free_storage_##name(struct cqueue_##name *c) { \
+        free(c->start); \
+    } \
+    UNUSED_STATIC_INLINE \
+    void cqueue_realloc_##name(struct cqueue_##name *c, size_t new_capacity) { \
+        cqueue_realloc_internal(&c->ci, safe_mul(new_capacity, \
+                                                 sizeof(__CQUEUE_TY_##name))); \
+    } \
+    UNUSED_STATIC_INLINE \
+    __CQUEUE_TY_##name *cqueue_appendp_##name(struct cqueue_##name *c) { \
+        if (c->write_ptr + 1 == c->read_ptr) \
+            cqueue_realloc_##name(c, (c->end - c->start) * 2 + 3); \
+        __CQUEUE_TY_##name *ret = c->write_ptr++; \
+        if (c->write_ptr == c->end) \
+            c->write_ptr = c->start; \
+        return ret; \
+    } \
+    UNUSED_STATIC_INLINE \
+    __CQUEUE_TY_##name *cqueue_shiftp_##name(struct cqueue_##name *c) { \
+        if (c->read_ptr == c->write_ptr) \
+            return NULL; \
+        __CQUEUE_TY_##name *ret = c->read_ptr++; \
+        if (c->read_ptr == c->end) \
+            c->read_ptr = c->start; \
+        return ret; \
+    } \
+    UNUSED_STATIC_INLINE \
+    size_t cqueue_length_##name(const struct cqueue_name *c) { \
+        return ((c->write_ptr - c->start) - (c->read_ptr - c->start)) \
+            % (c->end - c->start); \
+    } \
+    typedef char __plz_end_decl_cqueue_with_semicolon_##name