Fix: lttng-test build failure for kernels < 3.0

Fixes an undefined reference to kstrtouint_from_user.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/probes/lttng-test.c b/probes/lttng-test.c
index 2a66f4554374abfebf1dee82fb1b930c576956f0..bd9f5f89f37cabd0eb1c25b38ab90dcf7fc39dca 100644 (file)
--- a/probes/lttng-test.c
+++ b/probes/lttng-test.c
@@ -28,6 +28,7 @@
 #include "../lttng-events.h"
 #include "../lttng-tracer.h"
 #include "../wrapper/tracepoint.h"
+#include "../wrapper/kstrtox.h"
 
 #define TP_MODULE_NOAUTOLOAD
 #define LTTNG_PACKAGE_BUILD
@@ -76,7 +77,7 @@ ssize_t lttng_test_filter_event_write(struct file *file, const char __user *user
        int ret;
 
        /* Get the number of iterations */
-       ret = kstrtouint_from_user(user_buf, count, 10, &nr_iter);
+       ret = lttng_kstrtouint_from_user(user_buf, count, 10, &nr_iter);
        if (ret) {
                written = ret;
                goto end;

diff --git a/wrapper/kstrtox.h b/wrapper/kstrtox.h
new file mode 100644 (file)
index 0000000..0f0666f
--- /dev/null
+++ b/wrapper/kstrtox.h
@@ -0,0 +1,58 @@
+#ifndef _LTTNG_WRAPPER_KSTRTOX_H
+#define _LTTNG_WRAPPER_KSTRTOX_H
+
+/*
+ * wrapper/kstrtox.h
+ *
+ * Copyright (C) 2015 Michael Jeanson <mjeanson@efficios.com>
+ *
+ * This 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; only
+ * version 2.1 of the License.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/version.h>
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,0,0))
+
+/* Excludes final \0. */
+#define LTTNG_MAX_UINT_CHAR 10
+
+static inline
+int __must_check lttng_kstrtouint_from_user(const char __user *ubuf,
+               size_t count, unsigned int base, unsigned int *res)
+{
+       unsigned int _res;
+       char kbuf[LTTNG_MAX_UINT_CHAR + 1], *endptr;
+
+       memset(kbuf, 0, sizeof(kbuf));
+       if (copy_from_user(kbuf, ubuf, min_t(size_t, LTTNG_MAX_UINT_CHAR, count)))
+               return -EFAULT;
+
+       _res = simple_strtoul(kbuf, &endptr, base);
+       if (!endptr)
+               return -EINVAL;
+
+       *res = _res;
+       return 0;
+}
+#else
+static inline
+int __must_check lttng_kstrtouint_from_user(const char __user *ubuf,
+               size_t count, unsigned int base, unsigned int *res)
+{
+       return kstrtouint_from_user(ubuf, count, base, res);
+}
+#endif
+
+#endif /* _LTTNG_WRAPPER_KSTRTOX_H */