1 files changed, 56 insertions, 0 deletions
diff --git a/py/pystack.c b/py/pystack.c
new file mode 100644
index 0000000000..767c307e9a
--- /dev/null
+++ b/py/pystack.c
@@ -0,0 +1,56 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdio.h>
+
+#include "py/runtime.h"
+
+#if MICROPY_ENABLE_PYSTACK
+
+void mp_pystack_init(void *start, void *end) {
+    MP_STATE_THREAD(pystack_start) = start;
+    MP_STATE_THREAD(pystack_end) = end;
+    MP_STATE_THREAD(pystack_cur) = start;
+}
+
+void *mp_pystack_alloc(size_t n_bytes) {
+    n_bytes = (n_bytes + (MICROPY_PYSTACK_ALIGN - 1)) & ~(MICROPY_PYSTACK_ALIGN - 1);
+    #if MP_PYSTACK_DEBUG
+    n_bytes += MICROPY_PYSTACK_ALIGN;
+    #endif
+    if (MP_STATE_THREAD(pystack_cur) + n_bytes > MP_STATE_THREAD(pystack_end)) {
+        // out of memory in the pystack
+        mp_raise_recursion_depth();
+    }
+    void *ptr = MP_STATE_THREAD(pystack_cur);
+    MP_STATE_THREAD(pystack_cur) += n_bytes;
+    #if MP_PYSTACK_DEBUG
+    *(size_t*)(MP_STATE_THREAD(pystack_cur) - MICROPY_PYSTACK_ALIGN) = n_bytes;
+    #endif
+    return ptr;
+}
+
+#endif