Initial import

libc/runtime/bfree.c

@@ -0,0 +1,40 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ This program is free software; you can redistribute it and/or modify         │
+│ it under the terms of the GNU General Public License as published by         │
+│ the Free Software Foundation; version 2 of the License.                      │
+│                                                                              │
+│ This program is distributed in the hope that it will be useful, but          │
+│ WITHOUT ANY WARRANTY; without even the implied warranty of                   │
+│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU             │
+│ General Public License for more details.                                     │
+│                                                                              │
+│ You should have received a copy of the GNU General Public License            │
+│ along with this program; if not, write to the Free Software                  │
+│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
+│ 02110-1301 USA                                                               │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
+#include "libc/calls/calls.h"
+#include "libc/runtime/buffer.h"
+#include "libc/runtime/mappings.h"
+
+void bfree(struct GuardedBuffer *b) {
+  int mr;
+  size_t mi;
+  struct AddrSize az;
+  struct MemoryCoord mc;
+  if (b->p) {
+    mc = ADDRSIZE_TO_COORD(b->p, 1);
+    mi = findmapping(mc.y);
+    assert(mi > 0);
+    assert(ISOVERLAPPING(mc, _mm.p[mi - 1]));
+    az = COORD_TO_ADDRSIZE(_mm.p[mi - 1]);
+    mr = munmap(az.addr, az.size);
+    assert(mr != -1);
+    b->p = NULL;
+  }
+}