int _modbus_rtu_select(modbus_t *ctx, fd_set *rfds, struct timeval *tv, int length_to_read)
{
int s_rc;
#if defined(_WIN32)
s_rc = win32_ser_select(&(((modbus_rtu_t*)ctx->backend_data)->w_ser), length_to_read, tv);
if (s_rc == 0) {
errno = ETIMEDOUT;
return -1;
}
if (s_rc < 0) {
_error_print(ctx, "select");
if (ctx->error_recovery && (errno == EBADF)) {
modbus_close(ctx);
modbus_connect(ctx);
errno = EBADF;
return -1;
} else {
return -1;
}
}
#else
while ((s_rc = select(ctx->s+1, rfds, NULL, NULL, tv)) == -1) {
if (errno == EINTR) {
if (ctx->debug) {
fprintf(stderr, "A non blocked signal was caught\n");
}
/* Necessary after an error */
FD_ZERO(rfds);
FD_SET(ctx->s, rfds);
} else {
_error_print(ctx, "select");
if (ctx->error_recovery && (errno == EBADF)) {
modbus_close(ctx);
modbus_connect(ctx);
errno = EBADF;
return -1;
} else {
return -1;
}
}
}
if (s_rc == 0) {
/* Timeout */
errno = ETIMEDOUT;
_error_print(ctx, "select");
return -1;
}
#endif
return s_rc;
}
int8_t _dynamixel_rtu_select(dynamixel_t *ctx, fd_set *rfds,
struct timeval *tv, uint8_t length_to_read) {
int s_rc;
#if defined(_WIN32)
s_rc = win32_ser_select(
&(((dynamixel_rtu_t*)ctx->backend_data)->w_ser),
length_to_read,
tv
);
if (s_rc == 0) {
errno = ETIMEDOUT;
return -1;
}
if (s_rc < 0) {
return -1;
}
#else
while ((s_rc = select(ctx->s+1, rfds, NULL, NULL, tv)) == -1) {
if (errno == EINTR) {
if (ctx->debug) {
fprintf(stderr, "A non blocked signal was caught\n");
}
/* Necessary after an error */
FD_ZERO(rfds);
FD_SET(ctx->s, rfds);
} else {
return -1;
}
}
if (s_rc == 0) {
/* Timeout */
errno = ETIMEDOUT;
return -1;
}
#endif
return s_rc;
}
int _modbus_rtu_select(modbus_t *ctx, fd_set *rfds, struct timeval *tv, int msg_length_computed, int msg_length)
{
int s_rc;
#if defined(_WIN32)
s_rc = win32_ser_select(&(((modbus_rtu_t*)ctx->backend_data)->w_ser), msg_length_computed, tv);
if (s_rc == 0) {
errno = ETIMEDOUT;
return -1;
}
if (s_rc < 0) {
_error_print(ctx, "select");
if (ctx->error_recovery && (errno == EBADF)) {
modbus_close(ctx);
modbus_connect(ctx);
errno = EBADF;
return -1;
} else {
return -1;
}
}
#else
while ((s_rc = select(ctx->s+1, rfds, NULL, NULL, tv)) == -1) {
if (errno == EINTR) {
if (ctx->debug) {
fprintf(stderr, "A non blocked signal was caught\n");
}
/* Necessary after an error */
FD_ZERO(rfds);
FD_SET(ctx->s, rfds);
} else {
_error_print(ctx, "select");
if (ctx->error_recovery && (errno == EBADF)) {
modbus_close(ctx);
modbus_connect(ctx);
errno = EBADF;
return -1;
} else {
return -1;
}
}
}
if (s_rc == 0) {
/* Timeout */
if (msg_length == (ctx->backend->header_length + 2 +
ctx->backend->checksum_length)) {
/* Optimization allowed because exception response is
the smallest trame in modbus protocol (3) so always
raise a timeout error.
Temporary error before exception analyze. */
errno = EMBUNKEXC;
} else {
errno = ETIMEDOUT;
_error_print(ctx, "select");
}
return -1;
}
#endif
return s_rc;
}
