[RFC PATCH mtd-utils 025/110] ubifs-utils: Add spinlock implementations

[Zhihao Cheng]

Add spinlock implementations, because there are some spinlocks
(eg. c->cnt_lock, c->buds_lock) used in UBIFS linux kernel libs.
The spinlock is implementated based on pthread mutex.

This is a preparation for replacing implementation of UBIFS utils with
linux kernel libs.

Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
---
 ubifs-utils/Makemodule.am     |  3 ++-
 ubifs-utils/common/spinlock.h | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 ubifs-utils/common/spinlock.h

diff --git a/ubifs-utils/Makemodule.am b/ubifs-utils/Makemodule.am
index 9e075071..7849114e 100644
--- a/ubifs-utils/Makemodule.am
+++ b/ubifs-utils/Makemodule.am
@@ -5,6 +5,7 @@ common_SOURCES = \
 	ubifs-utils/common/atomic.h \
 	ubifs-utils/common/bitops.h \
 	ubifs-utils/common/bitops.c \
+	ubifs-utils/common/spinlock.h \
 	ubifs-utils/common/kmem.h \
 	ubifs-utils/common/kmem.c \
 	ubifs-utils/common/defs.h \
@@ -39,7 +40,7 @@ mkfs_ubifs_SOURCES = \
 	$(common_SOURCES) \
 	ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
 
-mkfs_ubifs_LDADD = libmtd.a libubi.a $(ZLIB_LIBS) $(LZO_LIBS) $(ZSTD_LIBS) $(UUID_LIBS) $(LIBSELINUX_LIBS) $(OPENSSL_LIBS) -lm
+mkfs_ubifs_LDADD = libmtd.a libubi.a $(ZLIB_LIBS) $(LZO_LIBS) $(ZSTD_LIBS) $(UUID_LIBS) $(LIBSELINUX_LIBS) $(OPENSSL_LIBS) -lm -lpthread
 mkfs_ubifs_CPPFLAGS = $(AM_CPPFLAGS) $(ZLIB_CFLAGS) $(LZO_CFLAGS) $(ZSTD_CFLAGS) $(UUID_CFLAGS) $(LIBSELINUX_CFLAGS) \
 	-I$(top_srcdir)/ubi-utils/include -I$(top_srcdir)/ubifs-utils/common
 
diff --git a/ubifs-utils/common/spinlock.h b/ubifs-utils/common/spinlock.h
new file mode 100644
index 00000000..b9ed3938
--- /dev/null
+++ b/ubifs-utils/common/spinlock.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_SPINLOCK_H_
+#define __LINUX_SPINLOCK_H_
+
+#include <pthread.h>
+
+#define spinlock_t		pthread_mutex_t
+#define DEFINE_SPINLOCK(x)	pthread_mutex_t x = PTHREAD_MUTEX_INITIALIZER
+#define spin_lock_init(x)	pthread_mutex_init(x, NULL)
+
+#define spin_lock(x)		pthread_mutex_lock(x)
+#define spin_unlock(x)		pthread_mutex_unlock(x)
+
+#endif
-- 
2.13.6