Cleanup: Move all source files to src/

[deliverable/lttng-modules.git] / src / wrapper / random.c

diff --git a/src/wrapper/random.c b/src/wrapper/random.c
new file mode 100644 (file)
index 0000000..7b91fc7
--- /dev/null
+++ b/src/wrapper/random.c
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
+ *
+ * wrapper/random.c
+ *
+ * wrapper around bootid read. Read the boot id through the /proc filesystem.
+ *
+ * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#include <linux/errno.h>
+
+/* boot_id depends on sysctl */
+#if defined(CONFIG_SYSCTL)
+
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <wrapper/random.h>
+
+/*
+ * Returns string boot id.
+ */
+int wrapper_get_bootid(char *bootid)
+{
+       struct file *file;
+       int ret;
+       ssize_t len;
+       mm_segment_t old_fs;
+
+       file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
+       if (IS_ERR(file))
+               return PTR_ERR(file);
+
+       old_fs = get_fs();
+       set_fs(KERNEL_DS);
+
+       if (!file->f_op || !file->f_op->read) {
+               ret = -EINVAL;
+               goto end;
+       }
+
+       len = file->f_op->read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
+       if (len != BOOT_ID_LEN - 1) {
+               ret = -EINVAL;
+               goto end;
+       }
+
+       bootid[BOOT_ID_LEN - 1] = '\0';
+       ret = 0;
+end:
+       set_fs(old_fs);
+       filp_close(file, current->files);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(wrapper_get_bootid);
+
+#else
+
+int wrapper_get_bootid(char *bootid)
+{
+       return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(wrapper_get_bootid);
+
+#endif