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-rw-r--r--hurd/sysvshm.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/hurd/sysvshm.c b/hurd/sysvshm.c
new file mode 100644
index 0000000000..5d538a6373
--- /dev/null
+++ b/hurd/sysvshm.c
@@ -0,0 +1,97 @@
+/* SysV shared memory for Hurd.
+ Copyright (C) 2005-2015 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/>. */
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/shm.h>
+
+
+/* Description of an shm attachment. */
+struct sysvshm_attach
+{
+ /* Linked list. */
+ struct sysvshm_attach *next;
+
+ /* Map address. */
+ void *addr;
+
+ /* Map size. */
+ size_t size;
+};
+
+/* List of attachments. */
+static struct sysvshm_attach *sysvshm_list;
+
+/* A lock to protect the linked list of shared memory attachments. */
+static struct mutex sysvshm_lock = MUTEX_INITIALIZER;
+
+
+/* Adds a segment attachment. */
+error_t
+__sysvshm_add (void *addr, size_t size)
+{
+ struct sysvshm_attach *shm;
+
+ shm = malloc (sizeof (*shm));
+ if (shm == NULL)
+ return errno;
+
+ __mutex_lock (&sysvshm_lock);
+ shm->addr = addr;
+ shm->size = size;
+ shm->next = sysvshm_list;
+ sysvshm_list = shm;
+ __mutex_unlock (&sysvshm_lock);
+
+ return 0;
+}
+
+/* Removes a segment attachment. On success, returns 0 and sets *SIZE to its
+ size. Returns EINVAL if not found. */
+error_t
+__sysvshm_remove (void *addr, size_t *size)
+{
+ struct sysvshm_attach *shm;
+ struct sysvshm_attach **pshm = &sysvshm_list;
+
+ __mutex_lock (&sysvshm_lock);
+ shm = sysvshm_list;
+ while (shm != NULL)
+ {
+ shm = *pshm;
+ if (shm->addr == addr)
+ {
+ *pshm = shm->next;
+ *size = shm->size;
+ __mutex_unlock (&sysvshm_lock);
+ free (shm);
+ return 0;
+ }
+ pshm = &shm->next;
+ shm = shm->next;
+ }
+ __mutex_unlock (&sysvshm_lock);
+ return EINVAL;
+}