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authorRoland McGrath <roland@hack.frob.com>2015-04-17 09:02:19 -0700
committerRoland McGrath <roland@hack.frob.com>2015-04-17 09:02:19 -0700
commitd1e44df1fa5fefd8a083f6c1e909bbcdc97c6438 (patch)
treea76176eca62c0907dd7f135979312c8e55ad06a5 /sysdeps/nacl/dl-unmap-segments.h
parentf70925993ada98039250d46c62fb89c168b8f9d6 (diff)
downloadglibc-d1e44df1fa5fefd8a083f6c1e909bbcdc97c6438.tar.gz
Add arm-nacl port.
Diffstat (limited to 'sysdeps/nacl/dl-unmap-segments.h')
-rw-r--r--sysdeps/nacl/dl-unmap-segments.h65
1 files changed, 65 insertions, 0 deletions
diff --git a/sysdeps/nacl/dl-unmap-segments.h b/sysdeps/nacl/dl-unmap-segments.h
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+++ b/sysdeps/nacl/dl-unmap-segments.h
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+/* Unmap a shared object's segments. NaCl version.
+ Copyright (C) 2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _DL_UNMAP_SEGMENTS_H
+#define _DL_UNMAP_SEGMENTS_H 1
+
+#include <link.h>
+#include <sys/mman.h>
+
+/* There is always a big gap between the executable segment and the data
+ segments. Other code segments and data pages lie in there. So we must
+ unmap each segment individually (except for a codeless module). */
+
+static void __always_inline
+_dl_unmap_segments (struct link_map *l)
+{
+ if (l->l_contiguous)
+ /* Simple case. */
+ __munmap ((void *) l->l_map_start, l->l_map_end - l->l_map_start);
+ else
+ {
+ /* Normally l_phdr points into the RODATA segment, which we will
+ unmap in one iteration of the loop. So we cannot use it directly
+ throughout. */
+
+ struct { ElfW(Addr) start, end; } segments[l->l_phnum], *seg = segments;
+
+ for (const ElfW(Phdr) *ph = l->l_phdr; ph < &l->l_phdr[l->l_phnum]; ++ph)
+ if (ph->p_type == PT_LOAD)
+ {
+ seg->start = (l->l_addr + ph->p_vaddr) & -GLRO(dl_pagesize);
+ seg->end = (l->l_addr + ph->p_vaddr + ph->p_memsz
+ + GLRO(dl_pagesize) - 1) & -GLRO(dl_pagesize);
+ if (seg > segments && seg[-1].end == seg->start)
+ /* Coalesce two adjacent segments into one munmap call. */
+ seg[-1].end = seg->end;
+ else
+ ++seg;
+ }
+
+ do
+ {
+ --seg;
+ __munmap ((void *) seg->start, seg->end - seg->start);
+ }
+ while (seg > segments);
+ }
+}
+
+#endif /* dl-unmap-segments.h */