diff options
author | Ben Pfaff <blp@nicira.com> | 2011-05-06 12:34:46 -0700 |
---|---|---|
committer | Ben Pfaff <blp@nicira.com> | 2011-05-16 13:40:48 -0700 |
commit | 6879df6b58388ef7dbd8f27c9c152a2df902773d (patch) | |
tree | 96a397283d91b3402d6233164baa42014f55dc10 /lib/csum.c | |
parent | 0b9275b2c7ed2f88491898345e03618dbfbf4b0f (diff) |
csum: Annotate byte order to match actual usage.
The IP checksum algorithm yields identical results regardless of whether
arithmetic little-endian or big-endian, but in practice OVS only passes in
big-endian data, so it seems reasonable to annotate these functions that
way.
Diffstat (limited to 'lib/csum.c')
-rw-r--r-- | lib/csum.c | 22 |
1 files changed, 11 insertions, 11 deletions
@@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -24,7 +24,7 @@ * consists of a packet in network byte order, then the return value is a value * in network byte order, and if 'data' consists of a data structure in host * byte order, then the return value is in host byte order. */ -uint16_t +ovs_be16 csum(const void *data, size_t n) { return csum_finish(csum_continue(0, data, n)); @@ -34,7 +34,7 @@ csum(const void *data, size_t n) * the updated checksum. (To start a new checksum, pass 0 for 'partial'. To * obtain the finished checksum, pass the return value to csum_finish().) */ uint32_t -csum_add16(uint32_t partial, uint16_t new) +csum_add16(uint32_t partial, ovs_be16 new) { return partial + new; } @@ -43,7 +43,7 @@ csum_add16(uint32_t partial, uint16_t new) * the updated checksum. (To start a new checksum, pass 0 for 'partial'. To * obtain the finished checksum, pass the return value to csum_finish().) */ uint32_t -csum_add32(uint32_t partial, uint32_t new) +csum_add32(uint32_t partial, ovs_be32 new) { return partial + (new >> 16) + (new & 0xffff); } @@ -56,10 +56,10 @@ csum_add32(uint32_t partial, uint32_t new) uint32_t csum_continue(uint32_t partial, const void *data_, size_t n) { - const uint16_t *data = data_; + const ovs_be16 *data = data_; for (; n > 1; n -= 2, data++) { - partial = csum_add16(partial, get_unaligned_u16(data)); + partial = csum_add16(partial, get_unaligned_be16(data)); } if (n) { partial += *(uint8_t *) data; @@ -74,7 +74,7 @@ csum_continue(uint32_t partial, const void *data_, size_t n) * if the data consist of a packet in network byte order, then the return value * is a value in network byte order, and if the data are a data structure in * host byte order, then the return value is in host byte order. */ -uint16_t +ovs_be16 csum_finish(uint32_t partial) { while (partial >> 16) { @@ -86,8 +86,8 @@ csum_finish(uint32_t partial) /* Returns the new checksum for a packet in which the checksum field previously * contained 'old_csum' and in which a field that contained 'old_u16' was * changed to contain 'new_u16'. */ -uint16_t -recalc_csum16(uint16_t old_csum, uint16_t old_u16, uint16_t new_u16) +ovs_be16 +recalc_csum16(ovs_be16 old_csum, ovs_be16 old_u16, ovs_be16 new_u16) { /* Ones-complement arithmetic is endian-independent, so this code does not * use htons() or ntohs(). @@ -103,8 +103,8 @@ recalc_csum16(uint16_t old_csum, uint16_t old_u16, uint16_t new_u16) /* Returns the new checksum for a packet in which the checksum field previously * contained 'old_csum' and in which a field that contained 'old_u32' was * changed to contain 'new_u32'. */ -uint16_t -recalc_csum32(uint16_t old_csum, uint32_t old_u32, uint32_t new_u32) +ovs_be16 +recalc_csum32(ovs_be16 old_csum, ovs_be32 old_u32, ovs_be32 new_u32) { return recalc_csum16(recalc_csum16(old_csum, old_u32, new_u32), old_u32 >> 16, new_u32 >> 16); |