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diff --git a/gdb/testsuite/gdb.base/find-unmapped.c b/gdb/testsuite/gdb.base/find-unmapped.c
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+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2012 Free Software Foundation, Inc.
+
+ 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; either version 3 of the License, or
+ (at your option) any later version.
+
+ 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, see <http://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <string.h>
+
+#define CHUNK_SIZE 16000 /* same as findcmd.c's */
+
+void *global_var_0;
+void *global_var_1;
+void *global_var_2;
+
+void
+breakpt ()
+{
+ /* Nothing. */
+}
+
+int
+main (void)
+{
+ void *p;
+ size_t pg_size;
+ int pg_count;
+ void *unmapped_page, *last_mapped_page, *first_mapped_page;
+
+ /*
+ Map enough pages to cover at least CHUNK_SIZE, and one extra page. We
+ then unmap the last page.
+
+ From gdb we can then perform find commands into unmapped region, gdb
+ should give an error.
+
+ .-- global_var_0 .-- global_var_1
+ | | .-- global_var_2
+ | | |
+ .----.----.----.----.----.
+ | | | | | |
+ '----'----'----'----'----'
+ |<- CHUNK_SIZE ->|
+
+ If CHUNK_SIZE equals page size then we'll get 3 pages, and if
+ CHUNK_SIZE is less than page size we'll get 2 pages. The test will
+ still work in these cases.
+
+ (1) We do a find from global_var_0 to global_var_2, this will fail when
+ loading the second chunk, as we know at least CHUNK_SIZE bytes are in
+ mapped space.
+
+ (2) We do a find from global_var_1 to global_var_2, this will fail when
+ loading the first chunk, assuming the CHUNK_SIZE is at least 16 bytes.
+
+ (3) We do a find from global_var_2 to (global_var_2 + 16), this too
+ will fail when loading the first chunk regardless of the chunk size.
+ */
+
+ pg_size = getpagesize ();
+ /* The +2 ensures the extra page. */
+ pg_count = CHUNK_SIZE / pg_size + 2;
+
+ p = mmap (0, pg_count * pg_size, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ if (p == MAP_FAILED)
+ {
+ perror ("mmap");
+ return EXIT_FAILURE;
+ }
+
+ memset (p, 0, pg_count * pg_size);
+
+ if (munmap (p + (pg_count - 1) * pg_size, pg_size) == -1)
+ {
+ perror ("munmap");
+ return EXIT_FAILURE;
+ }
+
+ first_mapped_page = p;
+ last_mapped_page = p + (pg_count - 2) * pg_size;
+ unmapped_page = last_mapped_page + pg_size;
+
+ /* Setup global variables we reference from gdb. */
+ global_var_0 = first_mapped_page;
+ global_var_1 = unmapped_page - 16;
+ global_var_2 = unmapped_page + 16;
+
+ breakpt ();
+
+ return EXIT_SUCCESS;
+}