[dpdk-dev] [PATCH v2 09/10] librte_mbuf: Add transform for rte_pktmbuf_mtod_offset()

[Cyril Chemparathy <cchemparathy@ezchip.com>]

This patch adds a coccinelle (see http://coccinelle.lip6.fr/)
transform to use the newly added rte_pktmbuf_mtod_offset() helper.  In
addition, we add a simple script to apply all available transforms to
a codebase.

Acked-by: Olivier Matz <olivier.matz@6wind.com>
Signed-off-by: Cyril Chemparathy <cchemparathy@ezchip.com>
---
 scripts/cocci.sh                | 64 ++++++++++++++++++++++++++++++++++
 scripts/cocci/mtod-offset.cocci | 76 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 140 insertions(+)
 create mode 100755 scripts/cocci.sh
 create mode 100644 scripts/cocci/mtod-offset.cocci

diff --git a/scripts/cocci.sh b/scripts/cocci.sh
new file mode 100755
index 0000000..3a70223
--- /dev/null
+++ b/scripts/cocci.sh
@@ -0,0 +1,64 @@
+#! /bin/sh
+
+# BSD LICENSE
+#
+# Copyright 2015 EZchip Semiconductor.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#   * Neither the name of EZchip Semiconductor nor the names of its
+#     contributors may be used to endorse or promote products derived
+#     from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# Apply coccinelle transforms.
+
+SRCTREE=$(readlink -f $(dirname $0)/..)
+COCCI=$SRCTREE/scripts/cocci
+[ -n "$SPATCH" ] || SPATCH=$(which spatch)
+
+PATCH_LIST="$@"
+[ -n "$PATCH_LIST" ] || PATCH_LIST=$(echo $COCCI/*.cocci)
+
+[ -x "$SPATCH" ] || (
+	echo "Coccinelle tools not installed."
+	exit 1
+)
+
+tmp=$(mktemp)
+
+for c in $PATCH_LIST; do
+	while true; do
+		echo -n "Applying $c..."
+		$SPATCH --sp-file $c -c --linux-spacing --very-quiet	\
+			--include-headers --preprocess			\
+			--in-place --dir $SRCTREE > $tmp
+		if [ -s $tmp ]; then
+			echo " changes applied, retrying."
+		else
+			echo " no change."
+			break;
+		fi
+	done
+done
+
+rm -f $tmp
diff --git a/scripts/cocci/mtod-offset.cocci b/scripts/cocci/mtod-offset.cocci
new file mode 100644
index 0000000..13134e9
--- /dev/null
+++ b/scripts/cocci/mtod-offset.cocci
@@ -0,0 +1,76 @@
+//
+// Replace explicit packet offset computations with rte_pktmbuf_mtod_offset().
+//
+@disable paren@
+typedef uint8_t;
+expression M, O;
+@@
+(
+- rte_pktmbuf_mtod(M, char *) + O
++ rte_pktmbuf_mtod_offset(M, char *, O)
+|
+- rte_pktmbuf_mtod(M, char *) - O
++ rte_pktmbuf_mtod_offset(M, char *, -O)
+|
+- rte_pktmbuf_mtod(M, unsigned char *) + O
++ rte_pktmbuf_mtod_offset(M, unsigned char *, O)
+|
+- rte_pktmbuf_mtod(M, unsigned char *) - O
++ rte_pktmbuf_mtod_offset(M, unsigned char *, -O)
+|
+- rte_pktmbuf_mtod(M, uint8_t *) + O
++ rte_pktmbuf_mtod_offset(M, uint8_t *, O)
+|
+- rte_pktmbuf_mtod(M, uint8_t *) - O
++ rte_pktmbuf_mtod_offset(M, uint8_t *, -O)
+)
+
+
+//
+// Fold subsequent offset terms into pre-existing offset used in
+// rte_pktmbuf_mtod_offset().
+//
+@disable paren@
+expression M, O1, O2;
+@@
+(
+- rte_pktmbuf_mtod_offset(M, char *, O1) + O2
++ rte_pktmbuf_mtod_offset(M, char *, O1 + O2)
+|
+- rte_pktmbuf_mtod_offset(M, char *, O1) - O2
++ rte_pktmbuf_mtod_offset(M, char *, O1 - O2)
+|
+- rte_pktmbuf_mtod_offset(M, unsigned char *, O1) + O2
++ rte_pktmbuf_mtod_offset(M, unsigned char *, O1 + O2)
+|
+- rte_pktmbuf_mtod_offset(M, unsigned char *, O1) - O2
++ rte_pktmbuf_mtod_offset(M, unsigned char *, O1 - O2)
+|
+- rte_pktmbuf_mtod_offset(M, uint8_t *, O1) + O2
++ rte_pktmbuf_mtod_offset(M, uint8_t *, O1 + O2)
+|
+- rte_pktmbuf_mtod_offset(M, uint8_t *, O1) - O2
++ rte_pktmbuf_mtod_offset(M, uint8_t *, O1 - O2)
+)
+
+
+//
+// Cleanup rules.  Fold in double casts, remove unnecessary paranthesis, etc.
+//
+@disable paren@
+expression M, O;
+type C, T;
+@@
+(
+- (C)rte_pktmbuf_mtod_offset(M, T, O)
++ rte_pktmbuf_mtod_offset(M, C, O)
+|
+- (rte_pktmbuf_mtod_offset(M, T, O))
++ rte_pktmbuf_mtod_offset(M, T, O)
+|
+- (C)rte_pktmbuf_mtod(M, T)
++ rte_pktmbuf_mtod(M, C)
+|
+- (rte_pktmbuf_mtod(M, T))
++ rte_pktmbuf_mtod(M, T)
+)
-- 
2.1.2