1 files changed, 107 insertions, 0 deletions
diff --git a/ports/unix/alloc.c b/ports/unix/alloc.c
new file mode 100644
index 000000000..ca12d025b
--- /dev/null
+++ b/ports/unix/alloc.c
@@ -0,0 +1,107 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014 Fabian Vogt
+ *
+ * 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 <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include "py/mpstate.h"
+#include "py/gc.h"
+
+#if MICROPY_EMIT_NATIVE || (MICROPY_PY_FFI && MICROPY_FORCE_PLAT_ALLOC_EXEC)
+
+#if defined(__OpenBSD__) || defined(__MACH__)
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+// The memory allocated here is not on the GC heap (and it may contain pointers
+// that need to be GC'd) so we must somehow trace this memory.  We do it by
+// keeping a linked list of all mmap'd regions, and tracing them explicitly.
+
+typedef struct _mmap_region_t {
+    void *ptr;
+    size_t len;
+    struct _mmap_region_t *next;
+} mmap_region_t;
+
+void mp_unix_alloc_exec(size_t min_size, void **ptr, size_t *size) {
+    // size needs to be a multiple of the page size
+    *size = (min_size + 0xfff) & (~0xfff);
+    *ptr = mmap(NULL, *size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (*ptr == MAP_FAILED) {
+        *ptr = NULL;
+    }
+
+    // add new link to the list of mmap'd regions
+    mmap_region_t *rg = m_new_obj(mmap_region_t);
+    rg->ptr = *ptr;
+    rg->len = min_size;
+    rg->next = MP_STATE_VM(mmap_region_head);
+    MP_STATE_VM(mmap_region_head) = rg;
+}
+
+void mp_unix_free_exec(void *ptr, size_t size) {
+    munmap(ptr, size);
+
+    // unlink the mmap'd region from the list
+    for (mmap_region_t **rg = (mmap_region_t**)&MP_STATE_VM(mmap_region_head); *rg != NULL; *rg = (*rg)->next) {
+        if ((*rg)->ptr == ptr) {
+            mmap_region_t *next = (*rg)->next;
+            m_del_obj(mmap_region_t, *rg);
+            *rg = next;
+            return;
+        }
+    }
+}
+
+void mp_unix_mark_exec(void) {
+    for (mmap_region_t *rg = MP_STATE_VM(mmap_region_head); rg != NULL; rg = rg->next) {
+        gc_collect_root(rg->ptr, rg->len / sizeof(mp_uint_t));
+    }
+}
+
+#if MICROPY_FORCE_PLAT_ALLOC_EXEC
+// Provide implementation of libffi ffi_closure_* functions in terms
+// of the functions above. On a normal Linux system, this save a lot
+// of code size.
+void *ffi_closure_alloc(size_t size, void **code);
+void ffi_closure_free(void *ptr);
+
+void *ffi_closure_alloc(size_t size, void **code) {
+    size_t dummy;
+    mp_unix_alloc_exec(size, code, &dummy);
+    return *code;
+}
+
+void ffi_closure_free(void *ptr) {
+    (void)ptr;
+    // TODO
+}
+#endif
+
+#endif // MICROPY_EMIT_NATIVE || (MICROPY_PY_FFI && MICROPY_FORCE_PLAT_ALLOC_EXEC)