Peter M. Groen / libmodbus

- avoid export of _modbus_rtu_set_rts and change its name to avoid
  confusion
- namespace RTU functions and constants
- use_rts is renamed rts
- add missing '_' in function name
- remove useless debug message in usual write
- wrong message about 'not supported'
- add check for TIOCM_RTS support
- block RTS flow control when not available

Thank you Ivo De Decker.

All related scripts and config files have been updated too.

The two modes are complementary, MODBUS_ERROR_RECOVERY_LINK handles
errors at data link level (bad file descriptor, timeout, etc) and
MODBUS_ERROR_RECOVERY_PROTOCOL checks Modbus error (eg. invalid
function code or trame length).

This change introduces the use of the Sleep function for Windows.
Some duplicated code has been moved from backends to modbus core.
A new debug message is now available when a flush occurs.

The unit tests are now based on this error recovery code.

Each function is decribed in one txt file. The file libmodbus.txt
offers an overview of the library.

It's possible to generate HTML and man outputs from the txt file.
The documentation can be generated only if you have the required
tools (asciidoc and xmlto).

Better results are obtained with AsciiDoc v8.6+

- removed ENOTCONN errno not supported
- set WINVER to Windows XP (and above) and add ws2_32.dll. So older
  Windows versions aren't supported.

Extracted from octo/libmodbus ff/ipv6 a6ae017c82e

Patch provided by Barry Brumbine.

- removed comment not required anymore with -Wall -Werror

Reported by Ivan Giuliani <giuliani.v@gmail.com>
It was not possible to use libmodbus outside of projects without
config.h file.

The inclusion has been removed from the public header.

Signed-off-by: Stéphane Raimbault <stephane.raimbault@gmail.com>

First, it's $host_os which should be checked, not $target (remember,
'build' is where we build, host is where the program will be run, and
target is only for compiler - for which system the compiler will
generate code.

Second, correct OS pattern - e.g. on debian with i586-mingw32msvc-gcc,
host_os is mingw32msvc, so we better for *mingw32*.

Also, it's better to call AC_CANONICAL_* for normalizing variables.

Build tested with `configure --host=i586-mingw32msvc` on Debian
GNU/Linux 5.0 (Lenny).

Cc: Александр Сёмуха <sav@mns.spb.ru>
Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Signed-off-by: Stéphane Raimbault <stephane.raimbault@gmail.com>

- check strlcpy in configure.ac
- test for empty device string
- test truncated device string

- move termios header in RTU backend
- move TCP headers in TCP backend
- use native serial on Win32 for Cygwin
- avoid too many defines

I prefer to remove the check rather than to add the solution used
by Wine as we don't care about the associated define:

AC_CHECK_HEADERS([ \
    ...
    netinet/ip.h \
    netinet/tcp.h \
    ...
],,,[
    #ifdef HAVE_NETINET_IP_H
    # include <netinet/ip.h>
    #endif
])

This change is asked by Barry Grumbine to fix build on OpenBSD

Some small modifications were neccessary to make libmodbus build using
a MinGW (cross-)compiler. Libtool is now configured to build DLL files
on Win32. The wsock32 library has been added to the list of libraries
to link against.

Signed-off-by: Stéphane Raimbault <stephane.raimbault@gmail.com>

The cycle will end on a 3.0 release instead of 2.2 as intended.
There are too many changes in the API to keep the same major number.

- partial revert of 93ce13656103cbb459ebd630d055a008dbb059f3
- it was a bit confusing to always edit modbus.h.in
- the header inclusion still unchanged (<modbus.h>)

The ID used at init time will be the device ID of the caller and
the server ID in request functions is the target to reach.

The library is now simpler to include (only one <modbus.h>)
To avoid confusion MB_VERSION defines have been renamed to
LIBMODBUS_VERSION.

This reverts commit df0cf7927249954f15e0aa85b02d21b990fa9af9.
Use <modbus.h> in tests.