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The following commit(s) were added to refs/heads/master by this push:
new 59da455fea libs/libc/crc16: Separate implementation of crc16xmodem
from crc16
59da455fea is described below
commit 59da455fea95ec1de2a8ad7695fb75db8e0e78fd
Author: chao an <anchao.arc...@bytedance.com>
AuthorDate: Mon Apr 7 12:26:49 2025 +0800
libs/libc/crc16: Separate implementation of crc16xmodem from crc16
keep default crc16 catalogue for CRC-16/XMODEM
Mapping crc16 implement to crc16xmodem
crc16 -> crc16xmodem
crc16part -> crc16xmodempart
- CRC-16/ACORN, CRC-16/LTE, CRC-16/V-41-MSB, XMODEM, ZMODEM
poly: 0x1021 initial seed: 0x0000, xor output: 0x0000
: width=16
: poly=0x1021
: init=0x0000
: refin=false
: refout=false
: xorout=0x0000
: check=0x31c3
: residue=0x0000
: name="CRC-16/XMODEM"
https://reveng.sourceforge.io/crc-catalogue/16.htm#crc.cat.crc-16-xmodem
Signed-off-by: chao an <anchao.arc...@bytedance.com>
---
include/nuttx/crc16.h | 47 ++++++++++++
libs/libc/misc/CMakeLists.txt | 2 +
libs/libc/misc/Make.defs | 2 +-
libs/libc/misc/lib_crc16.c | 94 +++++------------------
libs/libc/misc/{lib_crc16.c => lib_crc16xmodem.c} | 44 ++++++++---
5 files changed, 101 insertions(+), 88 deletions(-)
diff --git a/include/nuttx/crc16.h b/include/nuttx/crc16.h
index 5db5986ba4..26578c82b8 100644
--- a/include/nuttx/crc16.h
+++ b/include/nuttx/crc16.h
@@ -56,6 +56,9 @@ extern "C"
* Description:
* Continue CRC calculation on a part of the buffer.
*
+ * The default polynomial is 0x1021 (x^16 + x^12 + x^5 + 1)
+ * See crc16xmodempart()
+ *
****************************************************************************/
uint16_t crc16part(FAR const uint8_t *src, size_t len, uint16_t crc16val);
@@ -66,6 +69,9 @@ uint16_t crc16part(FAR const uint8_t *src, size_t len,
uint16_t crc16val);
* Description:
* Return a 16-bit CRC of the contents of the 'src' buffer, length 'len'
*
+ * The default polynomial is 0x1021 (x^16 + x^12 + x^5 + 1)
+ * See crc16xmodem()
+ *
****************************************************************************/
uint16_t crc16(FAR const uint8_t *src, size_t len);
@@ -158,6 +164,47 @@ uint16_t crc16ibmpart(FAR const uint8_t *src, size_t len,
uint16_t crc16ibm(FAR const uint8_t *src, size_t len);
+/****************************************************************************
+ * Name: crc16xmodempart
+ *
+ * Description:
+ * Continue CRC calculation on a part of the buffer.
+ *
+ * Return a 16-bit CRC-XMODEM of the contents of the 'src' buffer, length
+ * 'len', using the polynomial 0x1021 (x^16 + x^12 + x^5 + 1).
+ *
+ * The following checksums can, among others, be calculated by this
+ * function, depending on the value provided for the initial seed and
+ * the value the final calculated CRC is XORed with:
+ *
+ * - Alias: CRC-16/ACORN, CRC-16/LTE, CRC-16/V-41-MSB, XMODEM, ZMODEM
+ * https://reveng.sourceforge.io/crc-catalogue/16.htm#crc.cat.crc-16-xmodem
+ * poly: 0x1021 initial seed: 0x0000, xor output: 0x0000
+ *
+ ****************************************************************************/
+
+uint16_t crc16xmodempart(FAR const uint8_t *src, size_t len,
+ uint16_t crc16val);
+
+/****************************************************************************
+ * Name: crc16xmodem
+ *
+ * Description:
+ * Return a 16-bit CRC-XMODEM of the contents of the 'src' buffer, length
+ * 'len', using the polynomial 0x1021 (x^16 + x^12 + x^5 + 1).
+ *
+ * The following checksums can, among others, be calculated by this
+ * function, depending on the value provided for the initial seed and
+ * the value the final calculated CRC is XORed with:
+ *
+ * - Alias: CRC-16/ACORN, CRC-16/LTE, CRC-16/V-41-MSB, XMODEM, ZMODEM
+ * https://reveng.sourceforge.io/crc-catalogue/16.htm#crc.cat.crc-16-xmodem
+ * poly: 0x1021 initial seed: 0x0000, xor output: 0x0000
+ *
+ ****************************************************************************/
+
+uint16_t crc16xmodem(FAR const uint8_t *src, size_t len);
+
#undef EXTERN
#ifdef __cplusplus
}
diff --git a/libs/libc/misc/CMakeLists.txt b/libs/libc/misc/CMakeLists.txt
index d4c46b2a2d..fc032f5de3 100644
--- a/libs/libc/misc/CMakeLists.txt
+++ b/libs/libc/misc/CMakeLists.txt
@@ -83,6 +83,8 @@ list(
lib_crc32.c
lib_crc16.c
lib_crc16ccitt.c
+ lib_crc16ibm.c
+ lib_crc16xmodem.c
lib_crc8.c
lib_crc8ccitt.c
lib_crc8rohc.c
diff --git a/libs/libc/misc/Make.defs b/libs/libc/misc/Make.defs
index f174e990f0..a901639e9a 100644
--- a/libs/libc/misc/Make.defs
+++ b/libs/libc/misc/Make.defs
@@ -48,7 +48,7 @@ CSRCS += lib_dumpbuffer.c lib_dumpvbuffer.c lib_fnmatch.c
lib_debug.c
CSRCS += lib_crc64.c lib_crc32.c lib_crc16.c lib_crc16ccitt.c lib_crc8.c
CSRCS += lib_crc8ccitt.c lib_crc8table.c lib_crc8rohc.c lib_glob.c
CSRCS += lib_backtrace.c lib_ftok.c lib_err.c lib_instrument.c
-CSRCS += lib_crc16ibm.c
+CSRCS += lib_crc16ibm.c lib_crc16xmodem.c
# Keyboard driver encoder/decoder
diff --git a/libs/libc/misc/lib_crc16.c b/libs/libc/misc/lib_crc16.c
index 562ea3e97e..947aee8b84 100644
--- a/libs/libc/misc/lib_crc16.c
+++ b/libs/libc/misc/lib_crc16.c
@@ -1,4 +1,4 @@
-/************************************************************************************************
+/****************************************************************************
* libs/libc/misc/lib_crc16.c
*
* SPDX-License-Identifier: Apache-2.0
@@ -18,107 +18,49 @@
* License for the specific language governing permissions and limitations
* under the License.
*
-
************************************************************************************************/
+ ****************************************************************************/
-/* "Programmers may incorporate any or all code into their programs,
- * giving proper credit within the source. Publication of the
- * source routines is permitted so long as proper credit is given
- * to Stephen Satchell, Satchell Evaluations and Chuck Forsberg,
- * Omen Technology."
- */
-
-/* References:
- *
- * crc16_tab calculated by Mark G. Mendel, Network Systems Corporation.
- * crc16part() logic derived from article Copyright (C) 1986 Stephen
- * Satchell.
- */
-
-/************************************************************************************************
+/****************************************************************************
* Included Files
-
************************************************************************************************/
+ ****************************************************************************/
#include <sys/types.h>
#include <stdint.h>
#include <nuttx/crc16.h>
-/************************************************************************************************
- * Private Data
-
************************************************************************************************/
-
-/* crc16_tab calculated by Mark G. Mendel, Network Systems Corporation */
-
-static const uint16_t crc16_tab[256] =
-{
- 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
- 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
- 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
- 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
- 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
- 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
- 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
- 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
- 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
- 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
- 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
- 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
- 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
- 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
- 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
- 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
- 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
- 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
- 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
- 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
- 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
- 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
- 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
- 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
- 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
- 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
- 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
- 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
- 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
- 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
- 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
- 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
-};
-
-/************************************************************************************************
+/****************************************************************************
* Public Functions
-
************************************************************************************************/
+ ****************************************************************************/
-/************************************************************************************************
+/****************************************************************************
* Name: crc16part
*
* Description:
* Continue CRC calculation on a part of the buffer.
*
-
************************************************************************************************/
+ * The default polynomial is 0x1021 (x^16 + x^12 + x^5 + 1)
+ * See crc16xmodempart()
+ *
+ ****************************************************************************/
uint16_t crc16part(FAR const uint8_t *src, size_t len, uint16_t crc16val)
{
- size_t i;
-
- for (i = 0; i < len; i++)
- {
- crc16val = crc16_tab[((crc16val >> 8) & 0xff) ^
- src[i]] ^ (crc16val << 8);
- }
-
- return crc16val;
+ return crc16xmodempart(src, len, crc16val);
}
-/************************************************************************************************
+/****************************************************************************
* Name: crc16
*
* Description:
* Return a 16-bit CRC of the contents of the 'src' buffer, length 'len'
*
-
************************************************************************************************/
+ * The default polynomial is 0x1021 (x^16 + x^12 + x^5 + 1)
+ * See crc16xmodem()
+ *
+ ****************************************************************************/
uint16_t crc16(FAR const uint8_t *src, size_t len)
{
- return crc16part(src, len, 0);
+ return crc16xmodempart(src, len, 0);
}
diff --git a/libs/libc/misc/lib_crc16.c b/libs/libc/misc/lib_crc16xmodem.c
similarity index 75%
copy from libs/libc/misc/lib_crc16.c
copy to libs/libc/misc/lib_crc16xmodem.c
index 562ea3e97e..6b6c01de5f 100644
--- a/libs/libc/misc/lib_crc16.c
+++ b/libs/libc/misc/lib_crc16xmodem.c
@@ -1,5 +1,5 @@
/************************************************************************************************
- * libs/libc/misc/lib_crc16.c
+ * libs/libc/misc/lib_crc16xmodem.c
*
* SPDX-License-Identifier: Apache-2.0
*
@@ -29,7 +29,7 @@
/* References:
*
- * crc16_tab calculated by Mark G. Mendel, Network Systems Corporation.
+ * crc16xmodem_tab calculated by Mark G. Mendel, Network Systems Corporation.
* crc16part() logic derived from article Copyright (C) 1986 Stephen
* Satchell.
*/
@@ -47,9 +47,11 @@
* Private Data
************************************************************************************************/
-/* crc16_tab calculated by Mark G. Mendel, Network Systems Corporation */
+/* crc16xmodem_tab calculated by Mark G. Mendel, Network Systems Corporation
+ * The poly is 0x1021 (x^16 + x^12 + x^5 + 1)
+ */
-static const uint16_t crc16_tab[256] =
+static const uint16_t crc16xmodem_tab[256] =
{
0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
@@ -90,20 +92,31 @@ static const uint16_t crc16_tab[256] =
************************************************************************************************/
/************************************************************************************************
- * Name: crc16part
+ * Name: crc16xmodempart
*
* Description:
* Continue CRC calculation on a part of the buffer.
*
+ * Return a 16-bit CRC-XMODEM of the contents of the 'src' buffer, length
+ * 'len', using the polynomial 0x1021 (x^16 + x^12 + x^5 + 1).
+ *
+ * The following checksums can, among others, be calculated by this
+ * function, depending on the value provided for the initial seed and
+ * the value the final calculated CRC is XORed with:
+ *
+ * - Alias: CRC-16/ACORN, CRC-16/LTE, CRC-16/V-41-MSB, XMODEM, ZMODEM
+ * https://reveng.sourceforge.io/crc-catalogue/16.htm#crc.cat.crc-16-xmodem
+ * poly: 0x1021 initial seed: 0x0000, xor output: 0x0000
+ *
************************************************************************************************/
-uint16_t crc16part(FAR const uint8_t *src, size_t len, uint16_t crc16val)
+uint16_t crc16xmodempart(FAR const uint8_t *src, size_t len, uint16_t crc16val)
{
size_t i;
for (i = 0; i < len; i++)
{
- crc16val = crc16_tab[((crc16val >> 8) & 0xff) ^
+ crc16val = crc16xmodem_tab[((crc16val >> 8) & 0xff) ^
src[i]] ^ (crc16val << 8);
}
@@ -111,14 +124,23 @@ uint16_t crc16part(FAR const uint8_t *src, size_t len,
uint16_t crc16val)
}
/************************************************************************************************
- * Name: crc16
+ * Name: crc16xmodem
*
* Description:
- * Return a 16-bit CRC of the contents of the 'src' buffer, length 'len'
+ * Return a 16-bit CRC-XMODEM of the contents of the 'src' buffer, length
+ * 'len', using the polynomial 0x1021 (x^16 + x^12 + x^5 + 1).
+ *
+ * The following checksums can, among others, be calculated by this
+ * function, depending on the value provided for the initial seed and
+ * the value the final calculated CRC is XORed with:
+ *
+ * - Alias: CRC-16/ACORN, CRC-16/LTE, CRC-16/V-41-MSB, XMODEM, ZMODEM
+ * https://reveng.sourceforge.io/crc-catalogue/16.htm#crc.cat.crc-16-xmodem
+ * poly: 0x1021 initial seed: 0x0000, xor output: 0x0000
*
************************************************************************************************/
-uint16_t crc16(FAR const uint8_t *src, size_t len)
+uint16_t crc16xmodem(FAR const uint8_t *src, size_t len)
{
- return crc16part(src, len, 0);
+ return crc16xmodempart(src, len, 0);
}
