Peter M. Groen / libmodbus

Commit 6e6e2602a9c49b5cead4839adc4b91a03ca728a2

Authored by Stéphane Raimbault
1 parent 629dc1d7

Fix #375926 - modbus.c:164: error: `MSG_DONTWAIT' undeclared 

Reported and tested by Yishin Li.

Real fix #333455 - IPTOS_LOWDELAY not supported on cygwin
Thank to Yishin Li for the better problem description.
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Showing 3 changed files with 48 additions and 22 deletions
... ... @@ -7,8 +7,10 @@ libmodbus 2.2.0 (2009-05-01)
7 7 - modbus_param_t is smaller (2 int removed)
8 8 - Better error management
9 9 - Faster
10   -- Fix #333455 reported by Jeff Laughlin
  10 +- Fix #333455 reported by Jeff Laughlin and Yishin Li.
11 11 Cygwin IPTOS_LOWDELAY not supported on cygwin
  12 +- Fix #375926 - modbus.c:164: error: `MSG_DONTWAIT' undeclared
  13 + Reported and tested by Yishin Li.
12 14  
13 15 libmodbus 2.0.3 (2009-03-22)
14 16 ============================
... ...
configure.ac
  View file @6e6e260
... ... @@ -26,9 +26,10 @@ AC_HEADER_TIME
26 26 AC_TYPE_UINT16_T
27 27 AC_TYPE_UINT32_T
28 28 AC_TYPE_UINT8_T
29   -AC_CHECK_DECLS([IPTOS_LOWDELAY],
30   - [have_iptos_lowdelay=yes], [have_iptos_lowdelay=no],
31   - [#include <netinet/ip.h>])
  29 +
  30 +# Cygwin defines IPTOS_LOWDELAY but can't handle that flag so it's necessary to
  31 +# workaround that problem and Cygwin doesn't define MSG_DONTWAIT.
  32 +AC_CHECK_DECLS([__CYGWIN__])
32 33  
33 34 # Checks for library functions.
34 35 AC_FUNC_FORK
... ...
src/modbus.c
  View file @6e6e260
... ... @@ -152,23 +152,6 @@ static const int TAB_MAX_ADU_LENGTH[2] = {
152 152 MAX_ADU_LENGTH_TCP,
153 153 };
154 154  
155   -void modbus_flush(modbus_param_t *mb_param)
156   -{
157   - if (mb_param->type_com == RTU) {
158   - tcflush(mb_param->fd, TCIOFLUSH);
159   - } else {
160   - int ret;
161   - do {
162   - /* Extract the garbage from the socket */
163   - char devnull[MAX_ADU_LENGTH_TCP];
164   - ret = recv(mb_param->fd, devnull, MAX_ADU_LENGTH_TCP, MSG_DONTWAIT);
165   - if (mb_param->debug && ret > 0) {
166   - printf("%d bytes flushed\n", ret);
167   - }
168   - } while (ret > 0);
169   - }
170   -}
171   -
172 155 /* Treats errors and flush or close connection if necessary */
173 156 static void error_treat(modbus_param_t *mb_param, int code, const char *string)
174 157 {
... ... @@ -194,6 +177,42 @@ static void error_treat(modbus_param_t *mb_param, int code, const char *string)
194 177 }
195 178 }
196 179  
  180 +void modbus_flush(modbus_param_t *mb_param)
  181 +{
  182 + if (mb_param->type_com == RTU) {
  183 + tcflush(mb_param->fd, TCIOFLUSH);
  184 + } else {
  185 + int ret;
  186 + do {
  187 + /* Extract the garbage from the socket */
  188 + char devnull[MAX_ADU_LENGTH_TCP];
  189 +#if (!HAVE_DECL___CYGWIN__)
  190 + ret = recv(mb_param->fd, devnull, MAX_ADU_LENGTH_TCP, MSG_DONTWAIT);
  191 +#else
  192 + /* On Cygwin, it's a bit more complicated to not wait */
  193 + fd_set rfds;
  194 + struct timeval tv;
  195 +
  196 + tv.tv_sec = 0;
  197 + tv.tv_usec = 0;
  198 + FD_ZERO(&rfds);
  199 + FD_SET(mb_param->fd, &rfds);
  200 + ret = select(mb_param->fd+1, &rfds, NULL, NULL, &tv);
  201 + if (ret > 0) {
  202 + ret = recv(mb_param->fd, devnull, MAX_ADU_LENGTH_TCP, 0);
  203 + } else if (ret == -1) {
  204 + /* error_treat() doesn't call modbus_flush() in
  205 + this case (avoid infinite loop) */
  206 + error_treat(mb_param, SELECT_FAILURE, "Select failure");
  207 + }
  208 +#endif
  209 + if (mb_param->debug && ret > 0) {
  210 + printf("%d bytes flushed\n", ret);
  211 + }
  212 + } while (ret > 0);
  213 + }
  214 +}
  215 +
197 216 /* Computes the length of the expected response */
198 217 static unsigned int compute_response_length(modbus_param_t *mb_param,
199 218 uint8_t *query)
... ... @@ -1686,7 +1705,11 @@ static int modbus_connect_tcp(modbus_param_t *mb_param)
1686 1705 return ret;
1687 1706 }
1688 1707  
1689   -#ifdef HAVE_DECL_IPTOS_LOWDELAY
  1708 +#if (!HAVE_DECL___CYGWIN__)
  1709 + /**
  1710 + * Cygwin defines IPTOS_LOWDELAY but can't handle that flag so it's
  1711 + * necessary to workaround that problem.
  1712 + **/
1690 1713 /* Set the IP low delay option */
1691 1714 option = IPTOS_LOWDELAY;
1692 1715 ret = setsockopt(mb_param->fd, IPPROTO_TCP, IP_TOS,
... ...