Undo changes inserted in previous commit (included 2 unrelated changes)

2020-06-01, Mario de Sousa

Allow "" and NULL on TCP host and service (=> IP=INADDR_ANY, and port=0)

2020-06-01, Mario de Sousa

merge

2019-12-10, Mario de Sousa

change hton() and ntoh() so we don't use (u8 *) to (u16 *) casts. Some compilers incorrectly change the pointer to force alignment with even addresses.

2019-12-10, Mario de Sousa

Mario's fix for the pointer alignment problem. See changeset 4: 99009b24d401.

2019-12-10, bmakuc

Variables start_addr and count were read from query_packet using function mb_ntoh_safe. It looks like some compilers change the pointer alignment if the first byte starts at an odd address. Because mb_ntoh_safe uses pointers slave address and count (number of registers) were not read correctly from the buffer when several modbus slaves were present in network. In this temporary solution pointer aritmetics is replaced by simple 256 multiplication.

2019-11-27, bmakuc

Setting socket option so that TCP Modbus slave can re-use same port immediately after freeing it

2019-02-11, Edouard Tisserant

Let Makefile use default CFLAGS and CC instead of overriding them

2018-11-16, Edouard Tisserant

Remove incorrect inlines

2017-03-18, Andrey Skvortsov

Initial commit.

2017-03-05, Mario de Sousa