]> rtime.felk.cvut.cz Git - sojka/can-utils.git/blobdiff - slcanpty.c
Added slcand daemon contributed by Robert Haddon <robert.haddon@verari.com>
[sojka/can-utils.git] / slcanpty.c
index 07a05562a0c087b228c96364f3cdac962d0d3b76..cd18cd28ca49241942bd6fd5f5d9fba5c9a3217e 100644 (file)
@@ -44,6 +44,8 @@
 /* maximum rx buffer len: extended CAN frame with timestamp */
 #define SLC_MTU (sizeof("T1111222281122334455667788EA5F\r")+1)
 
+#define DEBUG
+
 static int asc2nibble(char c)
 {
 
@@ -59,23 +61,320 @@ static int asc2nibble(char c)
        return 16; /* error */
 }
 
+/* read data from pty, send CAN frames to CAN socket and answer commands */
+int pty2can(int pty, int socket, struct can_filter *fi,
+              int *is_open, int *tstamp)
+{
+       int nbytes;
+       char cmd;
+       char buf[200];
+       char replybuf[10]; /* for answers to received commands */
+       int ptr;
+       struct can_frame frame;
+       int tmp, i;
+
+       nbytes = read(pty, &buf, sizeof(buf)-1);
+       if (nbytes < 0) {
+               perror("read pty");
+               return 1;
+       }
+
+rx_restart:
+       /* remove trailing '\r' characters to be robust against some apps */
+       while (buf[0] == '\r' && nbytes > 0) {
+               for (tmp = 0; tmp < nbytes; tmp++)
+                       buf[tmp] = buf[tmp+1];
+               nbytes--;
+       }
+
+       if (!nbytes)
+               return 0;
+
+       cmd = buf[0];
+       buf[nbytes] = 0;
+
+#ifdef DEBUG
+       for (tmp = 0; tmp < nbytes; tmp++)
+               if (buf[tmp] == '\r')
+                       putchar('@');
+               else
+                       putchar(buf[tmp]);
+       printf("\n");
+#endif
+
+       /* check for filter configuration commands */
+       if (cmd == 'm' || cmd == 'M') {
+               buf[9] = 0; /* terminate filter string */
+               ptr = 9;
+#if 0
+               /* the filter is no SocketCAN filter :-( */
+
+               /* TODO: behave like a SJA1000 controller specific filter */
+
+               if (cmd == 'm') {
+                       fi->can_id = strtoul(buf+1,NULL,16);
+                       fi->can_id &= CAN_EFF_MASK;
+               } else {
+                       fi->can_mask = strtoul(buf+1,NULL,16);
+                       fi->can_mask &= CAN_EFF_MASK;
+               }
+
+               if (*is_open)
+                       setsockopt(socket, SOL_CAN_RAW,
+                                  CAN_RAW_FILTER, fi,
+                                  sizeof(struct can_filter));
+#endif
+               goto rx_out_ack;
+       }
+
+
+       /* check for timestamp on/off command */
+       if (cmd == 'Z') {
+               *tstamp = buf[1] & 0x01;
+               ptr = 2;
+               goto rx_out_ack;
+       }
+
+       /* check for 'O'pen command */
+       if (cmd == 'O') {
+               setsockopt(socket, SOL_CAN_RAW,
+                          CAN_RAW_FILTER, fi,
+                          sizeof(struct can_filter));
+               ptr = 1;
+               *is_open = 1;
+               goto rx_out_ack;
+       }
+
+       /* check for 'C'lose command */
+       if (cmd == 'C') {
+               setsockopt(socket, SOL_CAN_RAW, CAN_RAW_FILTER,
+                          NULL, 0);
+               ptr = 1;
+               *is_open = 0;
+               goto rx_out_ack;
+       }
+
+       /* check for 'V'ersion command */
+       if (cmd == 'V') {
+               sprintf(replybuf, "V1013\r");
+               tmp = strlen(replybuf);
+               ptr = 1;
+               goto rx_out;
+       }
+
+       /* check for serial 'N'umber command */
+       if (cmd == 'N') {
+               sprintf(replybuf, "N4242\r");
+               tmp = strlen(replybuf);
+               ptr = 1;
+               goto rx_out;
+       }
+
+       /* check for read status 'F'lags */
+       if (cmd == 'F') {
+               sprintf(replybuf, "F00\r");
+               tmp = strlen(replybuf);
+               ptr = 1;
+               goto rx_out;
+       }
+
+       /* correctly answer unsupported commands */
+       if (cmd == 'U') {
+               ptr = 2;
+               goto rx_out_ack;
+       }
+       if (cmd == 'S') {
+               ptr = 2;
+               goto rx_out_ack;
+       }
+       if (cmd == 's') {
+               ptr = 5;
+               goto rx_out_ack;
+       }
+       if (cmd == 'P' || cmd == 'A') {
+               ptr = 1;
+               goto rx_out_nack;
+       }
+       if (cmd == 'X') {
+               ptr = 2;
+               if (buf[1] & 0x01)
+                       goto rx_out_ack;
+               else
+                       goto rx_out_nack;
+       }
+
+       /* catch unknown commands */
+       if ((cmd != 't') && (cmd != 'T') &&
+           (cmd != 'r') && (cmd != 'R')) {
+               ptr = nbytes-1;
+               goto rx_out_nack;
+       }
+
+       if (cmd & 0x20) /* tiny chars 'r' 't' => SFF */
+               ptr = 4; /* dlc position tiiid */
+       else
+               ptr = 9; /* dlc position Tiiiiiiiid */
+
+       *(unsigned long long *) (&frame.data) = 0ULL; /* clear data[] */
+
+       if ((cmd | 0x20) == 'r' && buf[ptr] != '0') {
+
+               /* 
+                * RTR frame without dlc information!
+                * This is against the SLCAN spec but sent
+                * by a commercial CAN tool ... so we are
+                * robust against this protocol violation.
+                */
+
+               frame.can_dlc = buf[ptr]; /* save following byte */
+
+               buf[ptr] = 0; /* terminate can_id string */
+
+               frame.can_id = strtoul(buf+1, NULL, 16);
+               frame.can_id |= CAN_RTR_FLAG;
+
+               if (!(cmd & 0x20)) /* NO tiny chars => EFF */
+                       frame.can_id |= CAN_EFF_FLAG;
+
+               buf[ptr]  = frame.can_dlc; /* restore following byte */
+               frame.can_dlc = 0;
+               ptr--; /* we have no dlc component in the violation case */
+
+       } else {
+
+               if (!(buf[ptr] >= '0' && buf[ptr] < '9'))
+                       goto rx_out_nack;
+
+               frame.can_dlc = buf[ptr] - '0'; /* get dlc from ASCII val */
+
+               buf[ptr] = 0; /* terminate can_id string */
+
+               frame.can_id = strtoul(buf+1, NULL, 16);
+
+               if (!(cmd & 0x20)) /* NO tiny chars => EFF */
+                       frame.can_id |= CAN_EFF_FLAG;
+
+               if ((cmd | 0x20) == 'r') /* RTR frame */
+                       frame.can_id |= CAN_RTR_FLAG;
+
+               for (i = 0, ptr++; i < frame.can_dlc; i++) {
+
+                       tmp = asc2nibble(buf[ptr++]);
+                       if (tmp > 0x0F)
+                               goto rx_out_nack;
+                       frame.data[i] = (tmp << 4);
+                       tmp = asc2nibble(buf[ptr++]);
+                       if (tmp > 0x0F)
+                               goto rx_out_nack;
+                       frame.data[i] |= tmp;
+               }
+               /* point to last real data */
+               if (frame.can_dlc)
+                       ptr--;
+       }
+
+       nbytes = write(socket, &frame, sizeof(frame));
+       if (nbytes != sizeof(frame)) {
+               perror("write socket");
+               return 1;
+       }
+
+rx_out_ack:
+       replybuf[0] = '\r';
+       tmp = 1;
+       goto rx_out;
+rx_out_nack:
+       replybuf[0] = '\a';
+       tmp = 1;
+rx_out:
+       tmp = write(pty, replybuf, tmp);
+       if (tmp < 0) {
+               perror("write pty replybuf");
+               return 1;
+       }
+
+       /* check if there is another command in this buffer */
+       if (nbytes > ptr+1) {
+               for (tmp = 0, ptr++; ptr+tmp < nbytes; tmp++)
+                       buf[tmp] = buf[ptr+tmp];
+               nbytes = tmp;
+               goto rx_restart;
+       }
+
+       return 0;
+}
+
+/* read CAN frames from CAN interface and write it to the pty */
+int can2pty(int pty, int socket, int *tstamp)
+{
+       int nbytes;
+       char cmd;
+       char buf[SLC_MTU];
+       int ptr;
+       struct can_frame frame;
+       int i;
+
+       nbytes = read(socket, &frame, sizeof(frame));
+       if (nbytes != sizeof(frame)) {
+               perror("read socket");
+               return 1;
+       }
+
+       /* convert to slcan ASCII frame */
+       if (frame.can_id & CAN_RTR_FLAG)
+               cmd = 'R'; /* becomes 'r' in SFF format */
+       else
+               cmd = 'T'; /* becomes 't' in SFF format */
+
+       if (frame.can_id & CAN_EFF_FLAG)
+               sprintf(buf, "%c%08X%d", cmd,
+                       frame.can_id & CAN_EFF_MASK,
+                       frame.can_dlc);
+       else
+               sprintf(buf, "%c%03X%d", cmd | 0x20,
+                       frame.can_id & CAN_SFF_MASK,
+                       frame.can_dlc);
+
+       ptr = strlen(buf);
+
+       for (i = 0; i < frame.can_dlc; i++)
+               sprintf(&buf[ptr + 2*i], "%02X",
+                       frame.data[i]);
+
+       if (*tstamp) {
+               struct timeval tv;
+
+               if (ioctl(socket, SIOCGSTAMP, &tv) < 0)
+                       perror("SIOCGSTAMP");
+
+               sprintf(&buf[ptr + 2*frame.can_dlc], "%04lX",
+                       (tv.tv_sec%60)*1000 + tv.tv_usec/1000);
+       }
+
+       strcat(buf, "\r"); /* add terminating character */
+       nbytes = write(pty, buf, strlen(buf));
+       if (nbytes < 0) {
+               perror("write pty");
+               return 1;
+       }
+       fflush(NULL);
+
+       return 0;
+}
+
+
 int main(int argc, char **argv)
 {
        fd_set rdfs;
        int p; /* pty master file */ 
        int s; /* can raw socket */ 
-       int nbytes;
        struct sockaddr_can addr;
        struct termios topts;
        struct ifreq ifr;
        int running = 1;
-       char txcmd, rxcmd;
-       char txbuf[SLC_MTU];
-       char rxbuf[SLC_MTU];
-       int txp, rxp;
-       struct can_frame txf, rxf;
+       int tstamp = 0;
+       int is_open = 0;
        struct can_filter fi;
-       int tmp, i;
 
        /* check command line options */
        if (argc != 3) {
@@ -124,14 +423,17 @@ int main(int argc, char **argv)
        }
        addr.can_ifindex = ifr.ifr_ifindex;
 
+       /* disable reception of CAN frames until we are opened by 'O' */
+       setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);
+
        if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
                perror("bind");
                return 1;
        }
 
-       /* no filter content by default */
-       fi.can_id   = CAN_ERR_FLAG;
-       fi.can_mask = CAN_ERR_FLAG;
+       /* open filter by default */
+       fi.can_id   = 0;
+       fi.can_mask = 0;
 
        while (running) {
 
@@ -150,118 +452,16 @@ int main(int argc, char **argv)
                        continue;
                }
 
-               if (FD_ISSET(p, &rdfs)) {
-                       /* read rxdata from pty */
-                       nbytes = read(p, &rxbuf, sizeof(rxbuf)-1);
-                       if (nbytes < 0) {
-                               perror("read pty");
-                               return 1;
-                       }
-
-                       /* convert to struct can_frame rxf */
-                       rxcmd = rxbuf[0];
-
-                       /* check for filter configuration commands */
-                       if (rxcmd == 'm' || rxcmd == 'M') {
-                               rxbuf[9] = 0; /* terminate filter string */
-
-                               if (rxcmd == 'm') {
-                                       fi.can_id = strtoul(rxbuf+1,NULL,16);
-                                       fi.can_id &= CAN_EFF_MASK;
-                               } else {
-                                       fi.can_mask = strtoul(rxbuf+1,NULL,16);
-                                       fi.can_mask &= CAN_EFF_MASK;
-                               }
-
-                               /* set only when both values are defined */
-                               if (fi.can_id   != CAN_ERR_FLAG &&
-                                   fi.can_mask != CAN_ERR_FLAG)
-                                       setsockopt(s, SOL_CAN_RAW,
-                                                  CAN_RAW_FILTER, &fi,
-                                                  sizeof(struct can_filter));
-                       }
-
-                       if ((rxcmd != 't') && (rxcmd != 'T') &&
-                           (rxcmd != 'r') && (rxcmd != 'R'))
-                               continue;
-
-                       if (rxcmd & 0x20) /* tiny chars 'r' 't' => SFF */
-                               rxp = 4; /* dlc position tiiid */
-                       else
-                               rxp = 9; /* dlc position Tiiiiiiiid */
-
-                       if (!((rxbuf[rxp] >= '0') && (rxbuf[rxp] < '9')))
-                               continue;
-
-                       rxf.can_dlc = rxbuf[rxp] & 0x0F; /* get can_dlc */
-
-                       rxbuf[rxp] = 0; /* terminate can_id string */
-
-                       rxf.can_id = strtoul(rxbuf+1, NULL, 16);
-
-                       if (!(rxcmd & 0x20)) /* NO tiny chars => EFF */
-                               rxf.can_id |= CAN_EFF_FLAG;
-
-                       if ((rxcmd | 0x20) == 'r') /* RTR frame */
-                               rxf.can_id |= CAN_RTR_FLAG;
-
-                       *(unsigned long long *) (&rxf.data) = 0ULL; /* clear */
-
-                       for (i = 0, rxp++; i < rxf.can_dlc; i++) {
-
-                               tmp = asc2nibble(rxbuf[rxp++]);
-                               if (tmp > 0x0F)
-                                       continue;
-                               rxf.data[i] = (tmp << 4);
-                               tmp = asc2nibble(rxbuf[rxp++]);
-                               if (tmp > 0x0F)
-                                       continue;
-                               rxf.data[i] |= tmp;
-                       }
-
-                       nbytes = write(s, &rxf, sizeof(rxf));
-                       if (nbytes != sizeof(rxf)) {
-                               perror("write socket");
-                               return 1;
-                       }
+               if (FD_ISSET(p, &rdfs))
+                       if (pty2can(p, s, &fi, &is_open, &tstamp)) {
+                       running = 0;
+                       continue;
                }
 
-               if (FD_ISSET(s, &rdfs)) {
-                       /* read txframe from CAN interface */
-                       nbytes = read(s, &txf, sizeof(txf));
-                       if (nbytes != sizeof(txf)) {
-                               perror("read socket");
-                               return 1;
-                       }
-
-                       /* convert to slcan ASCII txf */
-                       if (txf.can_id & CAN_RTR_FLAG)
-                               txcmd = 'R'; /* becomes 'r' in SFF format */
-                       else
-                               txcmd = 'T'; /* becomes 't' in SFF format */
-
-                       if (txf.can_id & CAN_EFF_FLAG)
-                               sprintf(txbuf, "%c%08X%d", txcmd,
-                                       txf.can_id & CAN_EFF_MASK,
-                                       txf.can_dlc);
-                       else
-                               sprintf(txbuf, "%c%03X%d", txcmd | 0x20,
-                                       txf.can_id & CAN_SFF_MASK,
-                                       txf.can_dlc);
-
-                       txp = strlen(txbuf);
-
-                       for (i = 0; i < txf.can_dlc; i++)
-                               sprintf(&txbuf[txp + 2*i], "%02X",
-                                       txf.data[i]);
-
-                       strcat(txbuf, "\r"); /* add terminating character */
-                       nbytes = write(p, txbuf, strlen(txbuf));
-                       if (nbytes < 0) {
-                               perror("write pty");
-                               return 1;
-                       }
-                       fflush(NULL);
+               if (FD_ISSET(s, &rdfs))
+                       if (can2pty(p, s, &tstamp)) {
+                       running = 0;
+                       continue;
                }
        }