source: BAORadio/libindi/libindi/indiserver.c @ 629

/* INDI Server for protocol version 1.7.
 * Copyright (C) 2007 Elwood C. Downey ecdowney@clearskyinstitute.com

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 * argv lists names of Driver programs to run or sockets to connect for Devices.
 * Drivers are restarted if they exit or connection closes.
 * Each local Driver's stdin/out are assumed to provide INDI traffic and are
 *   connected here via pipes. Local Drivers' stderr are connected to our
 *   stderr with date stamp and driver name prepended.
 * We only support Drivers that advertise support for one Device. The problem
 *   with multiple Devices in one Driver is without a way to know what they
 *   _all_ are there is no way to avoid sending all messages to all Drivers.
 * Outbound messages are limited to Devices and Properties seen inbound.
 *   Messages to Devices on sockets always include Device so the chained
 *   indiserver will only pass back info from that Device.
 * All newXXX() received from one Client are echoed to all other Clients who
 *   have shown an interest in the same Device and property.
 *
 * Implementation notes:
 *
 * We fork each driver and open a server socket listening for INDI clients.
 * Then forever we listen for new clients and pass traffic between clients and
 * drivers, subject to optimizations based on sniffing messages for matching
 * Devices and Properties. Since one message might be destined to more than
 * one client or device, they are queued and only removed after the last
 * consumer is finished. XMLEle are converted to linear strings before being
 * sent to optimize write system calls and avoid blocking to slow clients.
 * Clients that get more than maxqsiz bytes behind are shut down.
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <signal.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <time.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>

#include "lilxml.h"
#include "indiapi.h"
#include "fq.h"

#define INDIPORT        7624            /* default TCP/IP port to listen */
#define REMOTEDVR       (-1234)         /* invalid PID to flag remote drivers */
#define MAXRBUF         4096            /* max read buffering here */
#define MAXWSIZ         4096            /* max bytes/write */
#define DEFMAXQSIZ      10              /* default max q behind, MB */

/* associate a usage count with queuded client or device message */
typedef struct {
    int count;                          /* number of consumers left */
    unsigned int cl;                    /* content length */
    char *cp;                           /* content: buf or malloced */
    char buf[MAXWSIZ];          /* local buf for most messages */
} Msg;

/* BLOB handling, NEVER is the default */
typedef enum {B_NEVER=0, B_ALSO, B_ONLY} BLOBHandling;

/* device + property name */
typedef struct {
    char dev[MAXINDIDEVICE];
    char name[MAXINDINAME];
    BLOBHandling blob;                  /* when to snoop BLOBs */
} Property;


/* record of each snooped property
typedef struct {
    Property prop;
    BLOBHandling blob;
} Property;
*/

struct
{
    const char *name;                      /* Path to FIFO for dynamic startups & shutdowns of drivers */
    int fd;
    FILE *fs;
} fifo;

/* info for each connected client */
typedef struct {
    int active;                         /* 1 when this record is in use */
    Property *props;                    /* malloced array of props we want */
    int nprops;                         /* n entries in props[] */
    int allprops;                       /* saw getProperties w/o device */
    BLOBHandling blob;                  /* when to send setBLOBs */
    int s;                              /* socket for this client */
    LilXML *lp;                         /* XML parsing context */
    FQ *msgq;                           /* Msg queue */
    unsigned int nsent;                         /* bytes of current Msg sent so far */
} ClInfo;
static ClInfo *clinfo;                  /*  malloced pool of clients */
static int nclinfo;                     /* n total (not active) */

/* info for each connected driver */
typedef struct {
    char name[MAXINDIDEVICE];           /* persistent name */
    char dev[MAXINDIDEVICE];            /* device served by this driver */
    int active;                         /* 1 when this record is in use */
    Property *sprops;                   /* malloced array of props we snoop */
    int nsprops;                        /* n entries in sprops[] */
    int pid;                            /* process id or REMOTEDVR if remote */
    int rfd;                            /* read pipe fd */
    int wfd;                            /* write pipe fd */
    int efd;                            /* stderr from driver, if local */
    int restarts;                       /* times process has been restarted */
    LilXML *lp;                         /* XML parsing context */
    FQ *msgq;                           /* Msg queue */
    unsigned int nsent;                 /* bytes of current Msg sent so far */
} DvrInfo;
static DvrInfo *dvrinfo;                /* malloced array of drivers */
static int ndvrinfo;                    /* n total */

static char *me;                        /* our name */
static int port = INDIPORT;             /* public INDI port */
static int verbose;                     /* chattiness */
static int lsocket;                     /* listen socket */
static char *ldir;                      /* where to log driver messages */
static int maxqsiz = (DEFMAXQSIZ*1024*1024); /* kill if these bytes behind */

static void logStartup(int ac, char *av[]);
static void usage (void);
static void noZombies (void);
static void noSIGPIPE (void);
static void indiFIFO(void);
static void indiRun (void);
static void indiListen (void);
static void newFIFO(void);
static void newClient (void);
static int newClSocket (void);
static void shutdownClient (ClInfo *cp);
static int readFromClient (ClInfo *cp);
static void startDvr (DvrInfo *dp);
static void startLocalDvr (DvrInfo *dp);
static void startRemoteDvr (DvrInfo *dp);
static int openINDIServer (char host[], int indi_port);
static void shutdownDvr (DvrInfo *dp, int restart);
static void q2RDrivers (const char *dev, Msg *mp, XMLEle *root);
static void q2SDrivers (int isblob, const char *dev, const char *name, Msg *mp,
    XMLEle *root);
static int q2Clients (ClInfo *notme, int isblob, const char *dev, const char *name,
    Msg *mp, XMLEle *root);
static void addSDevice (DvrInfo *dp, const char *dev, const char *name);
static Property *findSDevice (DvrInfo *dp, const char *dev, const char *name);
static void addClDevice (ClInfo *cp, const char *dev, const char *name, int isblob);
static int findClDevice (ClInfo *cp, const char *dev, const char *name);
static int readFromDriver (DvrInfo *dp);
static int stderrFromDriver (DvrInfo *dp);
static int msgQSize (FQ *q);
static void setMsgXMLEle (Msg *mp, XMLEle *root);
static void setMsgStr (Msg *mp, char *str);
static void freeMsg (Msg *mp);
static Msg *newMsg (void);
static int sendClientMsg (ClInfo *cp);
static int sendDriverMsg (DvrInfo *cp);
static void crackBLOB (const char *enableBLOB, BLOBHandling *bp);
static void crackBLOBHandling(const char *dev, const char *name, const char *enableBLOB, ClInfo *cp);
static void traceMsg (XMLEle *root);
static char *indi_tstamp (char *s);
static void logDMsg (XMLEle *root, const char *dev);
static void Bye(void);

int
main (int ac, char *av[])
{
        /* log startup */
        logStartup(ac, av);

        /* save our name */
        me = av[0];

        /* crack args */
        while ((--ac > 0) && ((*++av)[0] == '-')) {
            char *s;
            for (s = av[0]+1; *s != '\0'; s++)
                switch (*s) {
                case 'l':
                    if (ac < 2) {
                        fprintf (stderr, "-l requires log directory\n");
                        usage();
                    }
                    ldir = *++av;
                    ac--;
                    break;
                case 'm':
                    if (ac < 2) {
                        fprintf (stderr, "-m requires max MB behind\n");
                        usage();
                    }
                    maxqsiz = 1024*1024*atoi(*++av);
                    ac--;
                    break;
                case 'p':
                    if (ac < 2) {
                        fprintf (stderr, "-p requires port value\n");
                        usage();
                    }
                    port = atoi(*++av);
                    ac--;
                    break;
                case 'f':
                    if (ac < 2) {
                        fprintf (stderr, "-f requires fifo node\n");
                        usage();
                    }
                    fifo.name = *++av;
                    ac--;
                    break;
                case 'v':
                    verbose++;
                    break;
                default:
                    usage();
                }
        }

        /* at this point there are ac args in av[] to name our drivers */
        if (ac == 0 && !fifo.name)
            usage();

        /* take care of some unixisms */
        noZombies();
        noSIGPIPE();

        /* realloc seed for client pool */
        clinfo = (ClInfo *) malloc (1);
        nclinfo = 0;

        /* create driver info array all at once since size never changes */
        ndvrinfo = ac;
        dvrinfo = (DvrInfo *) calloc (ndvrinfo, sizeof(DvrInfo));

        /* start each driver */
        while (ac-- > 0) {
            strcpy(dvrinfo[ac].name, *av++);
            startDvr (&dvrinfo[ac]);
        }

        /* announce we are online */
        indiListen();

        /* Load up FIFO, if available */
        indiFIFO();

        /* handle new clients and all io */
        while (1)
            indiRun();

        /* whoa! */
        fprintf (stderr, "unexpected return from main\n");
        return (1);
}

/* record we have started and our args */
static void
logStartup(int ac, char *av[])
{
        int i;

        fprintf (stderr, "%s: startup: ", indi_tstamp(NULL));
        for (i = 0; i < ac; i++)
            fprintf (stderr, "%s ", av[i]);
        fprintf (stderr, "\n");
}

/* print usage message and exit (2) */
static void
usage(void)
{
        fprintf (stderr, "Usage: %s [options] driver [driver ...]\n", me);
        fprintf (stderr, "Purpose: server for local and remote INDI drivers\n");
        fprintf (stderr, "Code %s. Protocol %g.\n", "$Revision: 726523 $", INDIV);
        fprintf (stderr, "Options:\n");
        fprintf (stderr, " -l d     : log driver messages to <d>/YYYY-MM-DD.islog\n");
        fprintf (stderr, " -m m     : kill client if gets more than this many MB behind, default %d\n", DEFMAXQSIZ);
        fprintf (stderr, " -p p     : alternate IP port, default %d\n", INDIPORT);
        fprintf (stderr, " -f path  : Path to fifo for dynamic startup and shutdown of drivers.\n");
        fprintf (stderr, " -v       : show key events, no traffic\n");
        fprintf (stderr, " -vv      : -v + key message content\n");
        fprintf (stderr, " -vvv     : -vv + complete xml\n");
        fprintf (stderr, "driver    : executable or device@host[:port]\n");

        exit (2);
}

/* arrange for no zombies if drivers die */
static void
noZombies()
{
        struct sigaction sa;
        sa.sa_handler = SIG_IGN;
        sigemptyset(&sa.sa_mask);
#ifdef SA_NOCLDWAIT
        sa.sa_flags = SA_NOCLDWAIT;
#else
        sa.sa_flags = 0;
#endif
        (void)sigaction(SIGCHLD, &sa, NULL);
}

/* turn off SIGPIPE on bad write so we can handle it inline */
static void
noSIGPIPE()
{
        struct sigaction sa;
        sa.sa_handler = SIG_IGN;
        sigemptyset(&sa.sa_mask);
        (void)sigaction(SIGPIPE, &sa, NULL);
}

static DvrInfo * allocDvr ()
{
    DvrInfo *dp = NULL;
    int dvi;

/* try to reuse a drivber slot, else add one */
for (dvi = 0; dvi < ndvrinfo; dvi++)
    if (!(dp = &dvrinfo[dvi])->active)
        break;
if (dvi == ndvrinfo)
{
    /* grow dvrinfo */
    dvrinfo = (DvrInfo *) realloc (dvrinfo, (ndvrinfo+1)*sizeof(DvrInfo));
    if (!dvrinfo) {
        fprintf (stderr, "no memory for new drivers\n");
        Bye();
    }
    dp = &dvrinfo[ndvrinfo++];
}

/* rig up new dvrinfo entry */
memset (dp, 0, sizeof(*dp));
dp->active = 1;

return dp;

}

/* start the given INDI driver process or connection.
 * exit if trouble.
 */
static void
startDvr (DvrInfo *dp)
{
        if (strchr (dp->name, '@'))
            startRemoteDvr (dp);
        else
            startLocalDvr (dp);
}

/* start the given local INDI driver process.
 * exit if trouble.
 */
static void
startLocalDvr (DvrInfo *dp)
{
        Msg *mp;
        char buf[1024];
        int rp[2], wp[2], ep[2];
        int pid;

        /* build three pipes: r, w and error*/
        if (pipe (rp) < 0) {
            fprintf (stderr, "%s: read pipe: %s\n", indi_tstamp(NULL),
                                                            strerror(errno));
            Bye();
        }
        if (pipe (wp) < 0) {
            fprintf (stderr, "%s: write pipe: %s\n", indi_tstamp(NULL),
                                                            strerror(errno));
            Bye();
        }
        if (pipe (ep) < 0) {
            fprintf (stderr, "%s: stderr pipe: %s\n", indi_tstamp(NULL),
                                                            strerror(errno));
            Bye();
        }

        /* fork&exec new process */
        pid = fork();
        if (pid < 0) {
            fprintf (stderr, "%s: fork: %s\n", indi_tstamp(NULL), strerror(errno));
            Bye();
        }
        if (pid == 0) {
            /* child: exec name */
            int fd;

            /* rig up pipes */
            dup2 (wp[0], 0);    /* driver stdin reads from wp[0] */
            dup2 (rp[1], 1);    /* driver stdout writes to rp[1] */
            dup2 (ep[1], 2);    /* driver stderr writes to e[]1] */
            for (fd = 3; fd < 100; fd++)
                (void) close (fd);

            /* go -- should never return */
            execlp (dp->name, dp->name, NULL);
            fprintf (stderr, "%s: Driver %s: execlp: %s\n", indi_tstamp(NULL),
                                                dp->name, strerror(errno));
            _exit (1);  /* parent will notice EOF shortly */
        }

        /* don't need child's side of pipes */
        close (wp[0]);
        close (rp[1]);
        close (ep[1]);

        /* record pid, io channels, init lp and snoop list */
        dp->pid = pid;
        dp->rfd = rp[0];
        dp->wfd = wp[1];
        dp->efd = ep[0];
        dp->lp = newLilXML();
        dp->msgq = newFQ(1);
        dp->sprops = (Property*) malloc (1);    /* seed for realloc */
        dp->nsprops = 0;
        dp->nsent = 0;
        dp->active = 1;

        /* first message primes driver to report its properties -- dev known
         * if restarting
         */
        mp = newMsg();
        pushFQ (dp->msgq, mp);
        if (dp->dev[0])
            sprintf (buf, "<getProperties device='%s' version='%g'/>\n",
                                                            dp->dev, INDIV);
        else
            sprintf (buf, "<getProperties version='%g'/>\n", INDIV);
        setMsgStr (mp, buf);
        mp->count++;

        if (verbose > 0)
            fprintf (stderr, "%s: Driver %s: pid=%d rfd=%d wfd=%d efd=%d\n",
                    indi_tstamp(NULL), dp->name, dp->pid, dp->rfd, dp->wfd, dp->efd);
}

/* start the given remote INDI driver connection.
 * exit if trouble.
 */
static void
startRemoteDvr (DvrInfo *dp)
{
        Msg *mp;
        char dev[1024];
        char host[1024];
        char buf[1024];
        int indi_port, sockfd;

        /* extract host and port */
        indi_port = INDIPORT;
        if (sscanf (dp->name, "%[^@]@%[^:]:%d", dev, host, &indi_port) < 2) {
            fprintf (stderr, "Bad remote device syntax: %s\n", dp->name);
            Bye();
        }

        /* connect */
        sockfd = openINDIServer (host, indi_port);

        /* record flag pid, io channels, init lp and snoop list */
        dp->pid = REMOTEDVR;
        dp->rfd = sockfd;
        dp->wfd = sockfd;
        dp->lp = newLilXML();
        dp->msgq = newFQ(1);
        dp->sprops = (Property*) malloc (1);    /* seed for realloc */
        dp->nsprops = 0;
        dp->nsent = 0;
        dp->active = 1;

        /* N.B. storing name now is key to limiting outbound traffic to this
         * dev.
         */
        strncpy (dp->dev, dev, MAXINDIDEVICE-1);
        dp->dev[MAXINDIDEVICE-1] = '\0';

        /* Sending getProperties with device lets remote server limit its
         * outbound (and our inbound) traffic on this socket to this device.
         */
        mp = newMsg();
        pushFQ (dp->msgq, mp);
        sprintf (buf, "<getProperties device='%s' version='%g'/>\n",
                                                            dp->dev, INDIV);
        setMsgStr (mp, buf);
        mp->count++;

        if (verbose > 0)
            fprintf (stderr, "%s: Driver %s: socket=%d\n", indi_tstamp(NULL),
                                                            dp->name, sockfd);
}

/* open a connection to the given host and port or die.
 * return socket fd.
 */
static int
openINDIServer (char host[], int indi_port)
{
        struct sockaddr_in serv_addr;
        struct hostent *hp;
        int sockfd;

        /* lookup host address */
        hp = gethostbyname (host);
        if (!hp) {
            fprintf (stderr, "gethostbyname(%s): %s\n", host, strerror(errno));
            Bye();
        }

        /* create a socket to the INDI server */
        (void) memset ((char *)&serv_addr, 0, sizeof(serv_addr));
        serv_addr.sin_family = AF_INET;
        serv_addr.sin_addr.s_addr =
                            ((struct in_addr *)(hp->h_addr_list[0]))->s_addr;
        serv_addr.sin_port = htons(indi_port);
        if ((sockfd = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
            fprintf (stderr, "socket(%s,%d): %s\n", host, indi_port,strerror(errno));
            Bye();
        }

        /* connect */
        if (connect (sockfd,(struct sockaddr *)&serv_addr,sizeof(serv_addr))<0){
            fprintf (stderr, "connect(%s,%d): %s\n", host,indi_port,strerror(errno));
            Bye();
        }

        /* ok */
        return (sockfd);
}

/* create the public INDI Driver endpoint lsocket on port.
 * return server socket else exit.
 */
static void
indiListen ()
{
        struct sockaddr_in serv_socket;
        int sfd;
        int reuse = 1;

        /* make socket endpoint */
        if ((sfd = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
            fprintf (stderr, "%s: socket: %s\n", indi_tstamp(NULL), strerror(errno));
            Bye();
        }

        /* bind to given port for any IP address */
        memset (&serv_socket, 0, sizeof(serv_socket));
        serv_socket.sin_family = AF_INET;
        #ifdef SSH_TUNNEL
        serv_socket.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
        #else
        serv_socket.sin_addr.s_addr = htonl (INADDR_ANY);
        #endif
        serv_socket.sin_port = htons ((unsigned short)port);
        if (setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)) < 0){
            fprintf (stderr, "%s: setsockopt: %s\n", indi_tstamp(NULL),
                                                            strerror(errno));
            Bye();
        }
        if (bind(sfd,(struct sockaddr*)&serv_socket,sizeof(serv_socket)) < 0){
            fprintf (stderr, "%s: bind: %s\n", indi_tstamp(NULL), strerror(errno));
            Bye();
        }

        /* willing to accept connections with a backlog of 5 pending */
        if (listen (sfd, 5) < 0) {
            fprintf (stderr, "%s: listen: %s\n", indi_tstamp(NULL), strerror(errno));
            Bye();
        }

        /* ok */
        lsocket = sfd;
        if (verbose > 0)
            fprintf (stderr, "%s: listening to port %d on fd %d\n",
                                                indi_tstamp(NULL), port, sfd);
}

/* Attempt to open up FIFO */
static void indiFIFO(void)
{
    /* Open up FIFO, if available */
    if (fifo.name)
    {
        fifo.fd = open(fifo.name, O_RDONLY);
                  if (fifo.fd < 0)
                  {
                       fprintf(stderr, "%s: open(%s): %s.\n", indi_tstamp(NULL), fifo.name, strerror(errno));
                        Bye();
                   }

        fifo.fs = fdopen(fifo.fd, "r");
    }
}

/* service traffic from clients and drivers */
static void
indiRun(void)
{
        fd_set rs, ws;
        int maxfd=0;
        int i, s;

        /* init with no writers or readers */
        FD_ZERO(&ws);
        FD_ZERO(&rs);

        if (fifo.name && fifo.fd > 0)
        {
           FD_SET(fifo.fd, &rs);
           maxfd = fifo.fd;
        }

        /* always listen for new clients */
        FD_SET(lsocket, &rs);
        if (lsocket > maxfd)
                maxfd = lsocket;

        /* add all client readers and client writers with work to send */
        for (i = 0; i < nclinfo; i++) {
            ClInfo *cp = &clinfo[i];
            if (cp->active) {
                FD_SET(cp->s, &rs);
                if (nFQ(cp->msgq) > 0)
                    FD_SET(cp->s, &ws);
                if (cp->s > maxfd)
                    maxfd = cp->s;
            }
        }

        /* add all driver readers and driver writers with work to send */
        for (i = 0; i < ndvrinfo; i++)
        {
            DvrInfo *dp = &dvrinfo[i];
            if (dp->active)
            {
                FD_SET(dp->rfd, &rs);
                if (dp->rfd > maxfd)
                   maxfd = dp->rfd;
                if (dp->pid != REMOTEDVR)
                {
                   FD_SET(dp->efd, &rs);
                   if (dp->efd > maxfd)
                      maxfd = dp->efd;
                }
                if (nFQ(dp->msgq) > 0)
                {
                   FD_SET(dp->wfd, &ws);
                   if (dp->wfd > maxfd)
                       maxfd = dp->wfd;
                }
            }
        }

        /* wait for action */
        s = select (maxfd+1, &rs, &ws, NULL, NULL);
        if (s < 0) {
            fprintf (stderr, "%s: select(%d): %s\n", indi_tstamp(NULL), maxfd+1,
                                                            strerror(errno));
            Bye();
        }


        /* new command from FIFO? */
        if (s > 0 && FD_ISSET(fifo.fd, &rs)) {
            newFIFO();
            s--;
        }

        /* new client? */
        if (s > 0 && FD_ISSET(lsocket, &rs)) {
            newClient();
            s--;
        }

        /* message to/from client? */
        for (i = 0; s > 0 && i < nclinfo; i++) {
            ClInfo *cp = &clinfo[i];
            if (cp->active) {
                if (FD_ISSET(cp->s, &rs)) {
                    if (readFromClient(cp) < 0)
                        return; /* fds effected */
                    s--;
                }
                if (s > 0 && FD_ISSET(cp->s, &ws)) {
                    if (sendClientMsg(cp) < 0)
                        return; /* fds effected */
                    s--;
                }
            }
        }

        /* message to/from driver? */
        for (i = 0; s > 0 && i < ndvrinfo; i++) {
            DvrInfo *dp = &dvrinfo[i];
            if (dp->pid != REMOTEDVR && FD_ISSET(dp->efd, &rs)) {
                if (stderrFromDriver(dp) < 0)
                    return;     /* fds effected */
                s--;
            }
            if (s > 0 && FD_ISSET(dp->rfd, &rs)) {
                if (readFromDriver(dp) < 0)
                    return;     /* fds effected */
                s--;
            }
            if (s > 0 && FD_ISSET(dp->wfd, &ws) && nFQ(dp->msgq) > 0) {
                if (sendDriverMsg(dp) < 0)
                    return;     /* fds effected */
                s--;
            }
        }
}

/* Read commands from FIFO and process them. Start/stop drivers accordingly */
static void newFIFO(void)
{
    char line[MAXRBUF], tDriver[MAXRBUF], tConfig[MAXRBUF], tDev[MAXRBUF];
    static char *envDev=NULL, *envConfig=NULL;
    const char *delm = " ";
    char *token, *cp, *tp;
    DvrInfo *dp = NULL;
    int startCmd=0;

    if (envDev == NULL)
        envDev = (char *) malloc(MAXRBUF* sizeof(char));
    if (envConfig == NULL)
        envConfig = (char *) malloc(MAXRBUF * sizeof(char));

    while ( fgets (line, MAXRBUF, fifo.fs) != NULL)
    {
        fprintf(stderr, "FIFO: %s\n", line);

        tDev[0] = '\0', tDriver[0] = '\0', tConfig[0] = '\0', envDev[0] = '\0', envConfig[0] = '\0';
        cp = strdup(line);

        token = strsep(&cp, delm);

        if (!strcmp(token, "start") || !strcmp(token, "stop"))
        {
            //fprintf(stderr, "TOKEN: %s\n", token);

                if (!strcmp(token, "start"))
                    startCmd = 1;

                token = strsep(&cp, delm);

                if (!token)
                    continue;

               strncpy(tDriver, token, MAXRBUF);
               if (tp = strchr(tDriver, '\n'))
                   *tp = '\0';

               if (verbose)
                fprintf(stderr, "FIFO: Request for %s driver: %s\n", (startCmd == 1) ? "starting" : "stopping", tDriver);

               /* Find more name + config */
               token = strsep(&cp, delm);

               if (token)
               {
                 /* If config file detected, copy it */
                if (strstr(token, ".xml"))                 
                    strncpy(tConfig, token, MAXRBUF);
                /* Get rid of quotes */
                else if (strstr(token, "\"") || strstr(token, "'"))
                {
                    strncat(tDev, ++token, MAXRBUF);
                    while (token = strsep(&cp, delm) )
                   {
                     strcat(tDev, " ");
                     strncat(tDev, token, MAXRBUF);
                     if ( (tp=strchr(tDev, '\"')) || (tp=strchr(tDev, '\'')))
                     {
                         //tDev[strlen(tDev)-1] = '\0';
                         *tp='\0';
                         break;
                     }
                    }
                 }
                 else
                {
                     strncpy(tDev, token, MAXRBUF);
                     if (tp = strchr(tDev, '\n'))
                         *tp = '\0';
                 }

                  /* Find config, if there is any */
                  token = strsep(&cp, delm);
                  if (token)
                  {
                      /* Get rid of quotes */
                      if (strstr(token, "\"") || strstr(token, "'"))
                      {
                       strncat(tConfig, ++token, MAXRBUF);
                       while (token = strsep(&cp, delm) )
                       {
                          strcat(tConfig, " ");
                          strncat(tConfig, token, MAXRBUF);

                          if ( (tp=strchr(tConfig, '\"')) || (tp=strchr(tConfig, '\'')))
                          {
                                 //tConfig[strlen(tConfig)-1] = '\0';
                              *tp = '\0';
                              break;
                          }
                       }
                      }
                       else
                      {
                           strncpy(tConfig, token, MAXRBUF);
                           if (tp = strchr(tConfig, '\n'))
                               *tp = '\0';
                       }
                  }
              }

               /* Did we find device name? */
               if (tDev[0])
               {
                 snprintf(envDev, MAXRBUF, "INDIDEV=%s", tDev);

                 if (verbose)
                    fprintf(stderr, "With name: %s\n", envDev);

                 putenv(envDev);

                 //fprintf(stderr, "envionment check INDIDEV: %s\n", getenv("INDIDEV"));
               }

               /* Did we find config file */
               if (tConfig[0])
               {
                   snprintf(envConfig, MAXRBUF, "INDICONFIG=%s", tConfig);

                   if (verbose)
                    fprintf(stderr, "With config: %s\n", envConfig);

                   putenv(envConfig);
               }

               if (startCmd)
               {
                   if (verbose)
                        fprintf(stderr, "FIFO: Starting driver %s\n", tDriver);
                    dp = allocDvr();
                    strncpy(dp->name, tDriver, MAXINDIDEVICE);
                    strncpy(dp->dev, tDev, MAXINDIDEVICE);
                    startDvr (dp);
              }
               else
               {
                  for (dp = dvrinfo; dp < &dvrinfo[ndvrinfo]; dp++)
                   {
                       if (!strcmp(dp->name, tDriver))
                       {
                           /* If device name is given, check against it before shutting down */
                           if (tDev[0] && strcmp(dp->dev, tDev))
                               continue;

                           if (verbose)
                               fprintf(stderr, "FIFO: Shutting down driver: %s\n", tDriver);

                           shutdownDvr(dp, 0);

                               /* Inform clients that this driver is dead */
                               XMLEle *root = addXMLEle (NULL, "delProperty");
                               addXMLAtt(root, "device", dp->dev);
                               Msg * mp = newMsg();

                               q2Clients(NULL, 0, dp->dev, NULL, mp, root);
                               if (mp->count > 0)
                                   setMsgXMLEle (mp, root);
                               else
                                   freeMsg (mp);
                               delXMLEle (root);

                           break;

                       }
                   }
               }
         }
    }
}

/* prepare for new client arriving on lsocket.
 * exit if trouble.
 */
static void
newClient()
{
        ClInfo *cp = NULL;
        int s, cli;

        /* assign new socket */
        s = newClSocket ();

        /* try to reuse a clinfo slot, else add one */
        for (cli = 0; cli < nclinfo; cli++)
            if (!(cp = &clinfo[cli])->active)
                break;
        if (cli == nclinfo) {
            /* grow clinfo */
            clinfo = (ClInfo *) realloc (clinfo, (nclinfo+1)*sizeof(ClInfo));
            if (!clinfo) {
                fprintf (stderr, "no memory for new client\n");
                Bye();
            }
            cp = &clinfo[nclinfo++];
        }

        /* rig up new clinfo entry */
        memset (cp, 0, sizeof(*cp));
        cp->active = 1;
        cp->s = s;
        cp->lp = newLilXML();
        cp->msgq = newFQ(1);
        cp->props = malloc (1);
        cp->nsent = 0;

        if (verbose > 0) {
            struct sockaddr_in addr;
            socklen_t len = sizeof(addr);
            getpeername(s, (struct sockaddr*)&addr, &len);
            fprintf(stderr,"%s: Client %d: new arrival from %s:%d - welcome!\n",
                            indi_tstamp(NULL), cp->s, inet_ntoa(addr.sin_addr),
                                                        ntohs(addr.sin_port));
        }
}

/* read more from the given client, send to each appropriate driver when see
 * xml closure. also send all newXXX() to all other interested clients.
 * return -1 if had to shut down anything, else 0.
 */
static int
readFromClient (ClInfo *cp)
{
        char buf[MAXRBUF];
        int shutany = 0;
        int i, nr;

        /* read client */
        nr = read (cp->s, buf, sizeof(buf));
        if (nr <= 0) {
            if (nr < 0)
                fprintf (stderr, "%s: Client %d: read: %s\n", indi_tstamp(NULL),
                                                        cp->s, strerror(errno));
            else if (verbose > 0)
                fprintf (stderr, "%s: Client %d: read EOF\n", indi_tstamp(NULL),
                                                                        cp->s);
            shutdownClient (cp);
            return (-1);
        }

        /* process XML, sending when find closure */
        for (i = 0; i < nr; i++) {
            char err[1024];
            XMLEle *root = readXMLEle (cp->lp, buf[i], err);
            if (root) {
                char *roottag = tagXMLEle(root);
                const char *dev = findXMLAttValu (root, "device");
                const char *name = findXMLAttValu (root, "name");
                int isblob = !strcmp (tagXMLEle(root), "setBLOBVector");
                Msg *mp;

                if (verbose > 2) {
                    fprintf (stderr, "%s: Client %d: read ",indi_tstamp(NULL),cp->s);
                    traceMsg (root);
                } else if (verbose > 1) {
                    fprintf (stderr, "%s: Client %d: read <%s device='%s' name='%s'>\n",
                                    indi_tstamp(NULL), cp->s, tagXMLEle(root),
                                    findXMLAttValu (root, "device"),
                                    findXMLAttValu (root, "name"));
                }

                /* snag interested properties.
                 * N.B. don't open to alldevs if seen specific dev already, else
                 *   remote client connections start returning too much.
                 */
                if (dev[0])
                    addClDevice (cp, dev, name, isblob);
                else if (!strcmp (roottag, "getProperties") && !cp->nprops)
                    cp->allprops = 1;

                /* snag enableBLOB -- send to remote drivers too */
                if (!strcmp (roottag, "enableBLOB"))
                   // crackBLOB (pcdataXMLEle(root), &cp->blob);
                     crackBLOBHandling (dev, name, pcdataXMLEle(root), cp);

                /* build a new message -- set content iff anyone cares */
                mp = newMsg();

                /* send message to driver(s) responsible for dev */
                q2RDrivers (dev, mp, root);

                /* echo new* commands back to other clients */
                if (!strncmp (roottag, "new", 3)) {
                    if (q2Clients (cp, isblob, dev, name, mp, root) < 0)
                        shutany++;
                }

                /* set message content if anyone cares else forget it */
                if (mp->count > 0)
                    setMsgXMLEle (mp, root);
                else
                    freeMsg (mp);
                delXMLEle (root);

            } else if (err[0]) {
                char *ts = indi_tstamp(NULL);
                fprintf (stderr, "%s: Client %d: XML error: %s\n", ts,
                                                                cp->s, err);
                fprintf (stderr, "%s: Client %d: XML read: %.*s\n", ts,
                                                            cp->s, nr, buf);
                shutdownClient (cp);
                return (-1);
            }
        }

        return (shutany ? -1 : 0);
}

/* read more from the given driver, send to each interested client when see
 * xml closure. if driver dies, try restarting.
 * return 0 if ok else -1 if had to shut down anything.
 */
static int
readFromDriver (DvrInfo *dp)
{
        char buf[MAXRBUF];
        int shutany = 0;
        int i, nr;

        /* read driver */
        nr = read (dp->rfd, buf, sizeof(buf));
        if (nr <= 0) {
            if (nr < 0)
                fprintf (stderr, "%s: Driver %s: stdin %s\n", indi_tstamp(NULL),
                                                    dp->name, strerror(errno));
            else
                fprintf (stderr, "%s: Driver %s: stdin EOF\n",
                                                        indi_tstamp(NULL), dp->name);
            shutdownDvr (dp, 1);
            return (-1);
        }

        /* process XML, sending when find closure */
        for (i = 0; i < nr; i++) {
            char err[1024];
            XMLEle *root = readXMLEle (dp->lp, buf[i], err);
            if (root) {
                char *roottag = tagXMLEle(root);
                const char *dev = findXMLAttValu (root, "device");
                const char *name = findXMLAttValu (root, "name");
                int isblob = !strcmp (tagXMLEle(root), "setBLOBVector");
                Msg *mp;

                if (verbose > 2) {
                    fprintf(stderr, "%s: Driver %s: read ", indi_tstamp(0),dp->name);
                    traceMsg (root);
                } else if (verbose > 1) {
                    fprintf (stderr, "%s: Driver %s: read <%s device='%s' name='%s'>\n",
                                    indi_tstamp(NULL), dp->name, tagXMLEle(root),
                                    findXMLAttValu (root, "device"),
                                    findXMLAttValu (root, "name"));
                }

                /* that's all if driver is just registering a snoop */
                if (!strcmp (roottag, "getProperties")) {
                    addSDevice (dp, dev, name);
                    delXMLEle (root);
                    continue;
                }

                /* that's all if driver is just registering a BLOB mode */
                if (!strcmp (roottag, "enableBLOB")) {
                    Property *sp = findSDevice (dp, dev, name);
                    if (sp)
                        crackBLOB (pcdataXMLEle (root), &sp->blob);
                    delXMLEle (root);
                    continue;
                }

                /* snag device name if not known yet */
                if (!dp->dev[0] && dev[0]) {
                    strncpy (dp->dev, dev, MAXINDIDEVICE-1);
                    dp->dev[MAXINDIDEVICE-1] = '\0';
                }

                /* log messages if any and wanted */
                if (ldir)
                    logDMsg (root, dev);

                /* build a new message -- set content iff anyone cares */
                mp = newMsg();

                /* send to interested clients */
                if (q2Clients (NULL, isblob, dev, name, mp, root) < 0)
                    shutany++;

                /* send to snooping drivers */
                q2SDrivers (isblob, dev, name, mp, root);

                /* set message content if anyone cares else forget it */
                if (mp->count > 0)
                    setMsgXMLEle (mp, root);
                else
                    freeMsg (mp);
                delXMLEle (root);

            } else if (err[0]) {
                char *ts = indi_tstamp(NULL);
                fprintf (stderr, "%s: Driver %s: XML error: %s\n", ts,
                                                                dp->name, err);
                fprintf (stderr, "%s: Driver %s: XML read: %.*s\n", ts,
                                                            dp->name, nr, buf);
                shutdownDvr (dp, 1);
                return (-1);
            }
        }

        return (shutany ? -1 : 0);
}

/* read more from the given driver stderr, add prefix and send to our stderr.
 * return 0 if ok else -1 if had to restart.
 */
static int
stderrFromDriver (DvrInfo *dp)
{
        static char exbuf[MAXRBUF];
        static int nexbuf;
        int i, nr;

        /* read more */
        nr = read (dp->efd, exbuf+nexbuf, sizeof(exbuf)-nexbuf);
        if (nr <= 0) {
            if (nr < 0)
                fprintf (stderr, "%s: Driver %s: stderr %s\n", indi_tstamp(NULL),
                                                    dp->name, strerror(errno));
            else
                fprintf (stderr, "%s: Driver %s: stderr EOF\n",
                                                        indi_tstamp(NULL), dp->name);
            shutdownDvr (dp, 1);
            return (-1);
        }
        nexbuf += nr;

        /* prefix each whole line to our stderr, save extra for next time */
        for (i = 0; i < nexbuf; i++) {
            if (exbuf[i] == '\n') {
                fprintf (stderr, "%s: Driver %s: %.*s\n", indi_tstamp(NULL),
                                                            dp->name, i, exbuf);
                i++;                              /* count including nl */
                nexbuf -= i;                      /* remove from nexbuf */
                memmove (exbuf, exbuf+i, nexbuf); /* slide remaining to front */
                i = -1;                           /* restart for loop scan */
            }
        }

        return (0);
}

/* close down the given client */
static void
shutdownClient (ClInfo *cp)
{
        Msg *mp;

        /* close connection */
        shutdown (cp->s, SHUT_RDWR);
        close (cp->s);

        /* free memory */
        delLilXML (cp->lp);
        free (cp->props);

        /* decrement and possibly free any unsent messages for this client */
        while ((mp = (Msg*) popFQ(cp->msgq)) != NULL)
            if (--mp->count == 0)
                freeMsg (mp);
        delFQ (cp->msgq);

        /* ok now to recycle */
        cp->active = 0;

        if (verbose > 0)
            fprintf (stderr, "%s: Client %d: shut down complete - bye!\n",
                                                        indi_tstamp(NULL), cp->s);
}

/* close down the given driver and restart */
static void
shutdownDvr (DvrInfo *dp, int restart)
{
        Msg *mp;

        /* make sure it's dead, reclaim resources */
        if (dp->pid == REMOTEDVR) {
            /* socket connection */
            shutdown (dp->wfd, SHUT_RDWR);
            close (dp->wfd);    /* same as rfd */
        } else {
            /* local pipe connection */
            kill (dp->pid, SIGKILL);    /* we've insured there are no zombies */
            close (dp->wfd);
            close (dp->rfd);
            close (dp->efd);
        }

        /* free memory */
        free (dp->sprops);
        delLilXML (dp->lp);

        /* ok now to recycle */
        dp->active = 0;

        /* decrement and possibly free any unsent messages for this client */
        while ((mp = (Msg*) popFQ(dp->msgq)) != NULL)
            if (--mp->count == 0)
                freeMsg (mp);
        delFQ (dp->msgq);

        if (restart)
        {
            fprintf (stderr, "%s: Driver %s: restart #%d\n", indi_tstamp(NULL),
                                                    dp->name, ++dp->restarts);
            startDvr (dp);
        }

}

/* put Msg mp on queue of each driver responsible for dev, or all drivers
 * if dev not specified.
 */
static void
q2RDrivers (const char *dev, Msg *mp, XMLEle *root)
{
        int sawremote = 0;
        DvrInfo *dp;

        /* queue message to each interested driver.
         * N.B. don't send generic getProps to more than one remote driver,
         *   otherwise they all fan out and we get multiple responses back.
         */
        for (dp = dvrinfo; dp < &dvrinfo[ndvrinfo]; dp++) {
            int isremote = (dp->pid == REMOTEDVR);
            if (dp->active == 0)
                continue;
            if (dev[0] && dp->dev[0] && strcmp (dev, dp->dev))
                continue;       /* driver known to not support this dev */
            if (!dev[0] && isremote && sawremote)
                continue;       /* already sent generic to another remote */
            if (isremote)
                sawremote = 1;

            /* ok: queue message to this driver */
            mp->count++;
            pushFQ (dp->msgq, mp);
            if (verbose > 1)
                fprintf (stderr, "%s: Driver %s: queuing responsible for <%s device='%s' name='%s'>\n",
                                    indi_tstamp(NULL), dp->name, tagXMLEle(root),
                                    findXMLAttValu (root, "device"),
                                    findXMLAttValu (root, "name"));
        }
}

/* put Msg mp on queue of each driver snooping dev/name.
 * if BLOB always honor current mode.
 */
static void
q2SDrivers (int isblob, const char *dev, const char *name, Msg *mp, XMLEle *root)
{
        DvrInfo *dp;

        for (dp = dvrinfo; dp < &dvrinfo[ndvrinfo]; dp++) {
            Property *sp = findSDevice (dp, dev, name);

            /* nothing for dp if not snooping for dev/name or wrong BLOB mode */
            if (!sp)
                continue;
            if ((isblob && sp->blob==B_NEVER) || (!isblob && sp->blob==B_ONLY))
                continue;

            /* ok: queue message to this device */
            mp->count++;
            pushFQ (dp->msgq, mp);
            if (verbose > 1) {
                fprintf (stderr, "%s: Driver %s: queuing snooped <%s device='%s' name='%s'>\n",
                                    indi_tstamp(NULL), dp->name, tagXMLEle(root),
                                    findXMLAttValu (root, "device"),
                                    findXMLAttValu (root, "name"));
            }
        }
}

/* add dev/name to dp's snooping list.
 * init with blob mode set to B_NEVER.
 */
static void
addSDevice (DvrInfo *dp, const char *dev, const char *name)
{
        Property *sp;
        char *ip;

        /* no dups */
        sp = findSDevice (dp, dev, name);
        if (sp)
            return;

        /* add dev to sdevs list */
        dp->sprops = (Property*) realloc (dp->sprops,
                                            (dp->nsprops+1)*sizeof(Property));
        sp = &dp->sprops[dp->nsprops++];

        ip = sp->dev;
        strncpy (ip, dev, MAXINDIDEVICE-1);
        ip[MAXINDIDEVICE-1] = '\0';

        ip = sp->name;
        strncpy (ip, name, MAXINDINAME-1);
        ip[MAXINDINAME-1] = '\0';

        sp->blob = B_NEVER;

        if (verbose)
            fprintf (stderr, "%s: Driver %s: snooping on %s.%s\n", indi_tstamp(NULL),
                                                        dp->name, dev, name);
}

/* return Property if dp is snooping dev/name, else NULL.
 */
static Property *
findSDevice (DvrInfo *dp, const char *dev, const char *name)
{
        int i;

        for (i = 0; i < dp->nsprops; i++) {
            Property *sp = &dp->sprops[i];
            if (!strcmp (sp->dev, dev) &&
                    (!sp->name[0] || !strcmp(sp->name, name)))
                return (sp);
        }

        return (NULL);
}


/* put Msg mp on queue of each client interested in dev/name, except notme.
 * if BLOB always honor current mode.
 * return -1 if had to shut down any clients, else 0.
 */
static int
q2Clients (ClInfo *notme, int isblob, const char *dev, const char *name, Msg *mp, XMLEle *root)
{
        int shutany = 0;
        ClInfo *cp;
        int ql,i=0;

        /* queue message to each interested client */
        for (cp = clinfo; cp < &clinfo[nclinfo]; cp++) {
            /* cp in use? notme? want this dev/name? blob? */
            if (!cp->active || cp == notme)
                continue;
            if (findClDevice (cp, dev, name) < 0)
                continue;

            //if ((isblob && cp->blob==B_NEVER) || (!isblob && cp->blob==B_ONLY))
            if (!isblob && cp->blob==B_ONLY)
                continue;

            if (isblob)
            {
                if (cp->nprops > 0)
                {
                Property *pp = NULL;
                int blob_found=0;
                for (i = 0; i < cp->nprops; i++)
                {
                    pp = &cp->props[i];
                    if (!strcmp (pp->dev, dev) && (!strcmp(pp->name, name)))
                    {
                        blob_found = 1;
                        break;
                    }
                }

                if ( (blob_found && pp->blob == B_NEVER) || (blob_found==0 && cp->blob == B_NEVER) )
                    continue;
               }
               else if (cp->blob == B_NEVER)
                   continue;
           }

            /* shut down this client if its q is already too large */
            ql = msgQSize(cp->msgq);
            if (ql > maxqsiz) {
                if (verbose)
                    fprintf (stderr, "%s: Client %d: %d bytes behind, shutting down\n",
                                                    indi_tstamp(NULL), cp->s, ql);
                shutdownClient (cp);
                shutany++;
                continue;
            }

            /* ok: queue message to this client */
            mp->count++;
            pushFQ (cp->msgq, mp);
            if (verbose > 1)
                fprintf (stderr, "%s: Client %d: queuing <%s device='%s' name='%s'>\n",
                                    indi_tstamp(NULL), cp->s, tagXMLEle(root),
                                    findXMLAttValu (root, "device"),
                                    findXMLAttValu (root, "name"));
        }

        return (shutany ? -1 : 0);
}

/* return size of all Msqs on the given q */
static int
msgQSize (FQ *q)
{
        int i, l = 0;

        for (i = 0; i < nFQ(q); i++) {
            Msg *mp = (Msg *) peekiFQ(q,i);
            l += mp->cl;
        }

        return (l);
}

/* print root as content in Msg mp.
 */
static void
setMsgXMLEle (Msg *mp, XMLEle *root)
{
        /* want cl to only count content, but need room for final \0 */
        mp->cl = sprlXMLEle (root, 0);
        if (mp->cl < sizeof(mp->buf))
            mp->cp = mp->buf;
        else
            mp->cp = malloc (mp->cl+1);
        sprXMLEle (mp->cp, root, 0);
}

/* save str as content in Msg mp.
 */
static void
setMsgStr (Msg *mp, char *str)
{
        /* want cl to only count content, but need room for final \0 */
        mp->cl = strlen (str);
        if (mp->cl < sizeof(mp->buf))
            mp->cp = mp->buf;
        else
            mp->cp = malloc (mp->cl+1);
        strcpy (mp->cp, str);
}

/* return pointer to one new nulled Msg
 */
static Msg *
newMsg (void)
{
        return ((Msg *) calloc (1, sizeof(Msg)));
}

/* free Msg mp and everything it contains */
static void
freeMsg (Msg *mp)
{
        if (mp->cp && mp->cp != mp->buf)
            free (mp->cp);
        free (mp);
}

/* write the next chunk of the current message in the queue to the given
 * client. pop message from queue when complete and free the message if we are
 * the last one to use it. shut down this client if trouble.
 * N.B. we assume we will never be called with cp->msgq empty.
 * return 0 if ok else -1 if had to shut down.
 */
static int
sendClientMsg (ClInfo *cp)
{
        int nsend, nw;
        Msg *mp;

        /* get current message */
        mp = (Msg *) peekFQ (cp->msgq);

        /* send next chunk, never more than MAXWSIZ to reduce blocking */
        nsend = mp->cl - cp->nsent;
        if (nsend > MAXWSIZ)
            nsend = MAXWSIZ;
        nw = write (cp->s, &mp->cp[cp->nsent], nsend);

        /* shut down if trouble */
        if (nw <= 0) {
            if (nw == 0)
                fprintf (stderr, "%s: Client %d: write returned 0\n",
                                                    indi_tstamp(NULL), cp->s);
            else
                fprintf (stderr, "%s: Client %d: write: %s\n", indi_tstamp(NULL),
                                                    cp->s, strerror(errno));
            shutdownClient (cp);
            return (-1);
        }

        /* trace */
        if (verbose > 2) {
            fprintf(stderr, "%s: Client %d: sending msg copy %d nq %d:\n%.*s\n",
                                indi_tstamp(NULL), cp->s, mp->count, nFQ(cp->msgq),
                                nw, &mp->cp[cp->nsent]);
        } else if (verbose > 1) {
            fprintf(stderr, "%s: Client %d: sending %.50s\n", indi_tstamp(NULL),
                                                    cp->s, &mp->cp[cp->nsent]);
        }

        /* update amount sent. when complete: free message if we are the last
         * to use it and pop from our queue.
         */
        cp->nsent += nw;
        if (cp->nsent == mp->cl) {
            if (--mp->count == 0)
                freeMsg (mp);
            popFQ (cp->msgq);
            cp->nsent = 0;
        }

        return (0);
}

/* write the next chunk of the current message in the queue to the given
 * driver. pop message from queue when complete and free the message if we are
 * the last one to use it. restart this driver if touble.
 * N.B. we assume we will never be called with dp->msgq empty.
 * return 0 if ok else -1 if had to shut down.
 */
static int
sendDriverMsg (DvrInfo *dp)
{
        int nsend, nw;
        Msg *mp;

        /* get current message */
        mp = (Msg *) peekFQ (dp->msgq);

        /* send next chunk, never more than MAXWSIZ to reduce blocking */
        nsend = mp->cl - dp->nsent;
        if (nsend > MAXWSIZ)
            nsend = MAXWSIZ;
        nw = write (dp->wfd, &mp->cp[dp->nsent], nsend);

        /* restart if trouble */
        if (nw <= 0) {
            if (nw == 0)
                fprintf (stderr, "%s: Driver %s: write returned 0\n",
                                                    indi_tstamp(NULL), dp->name);
            else
                fprintf (stderr, "%s: Driver %s: write: %s\n", indi_tstamp(NULL),
                                                    dp->name, strerror(errno));
            shutdownDvr (dp, 1);
            return (-1);
        }

        /* trace */
        if (verbose > 2) {
            fprintf(stderr, "%s: Driver %s: sending msg copy %d nq %d:\n%.*s\n",
                            indi_tstamp(NULL), dp->name, mp->count, nFQ(dp->msgq),
                            nw, &mp->cp[dp->nsent]);
        } else if (verbose > 1) {
            fprintf(stderr, "%s: Driver %s: sending %.50s\n", indi_tstamp(NULL),
                                                dp->name, &mp->cp[dp->nsent]);
        }

        /* update amount sent. when complete: free message if we are the last
         * to use it and pop from our queue.
         */
        dp->nsent += nw;
        if (dp->nsent == mp->cl) {
            if (--mp->count == 0)
                freeMsg (mp);
            popFQ (dp->msgq);
            dp->nsent = 0;
        }

        return (0);
}

/* return 0 if cp may be interested in dev/name else -1
 */
static int
findClDevice (ClInfo *cp, const char *dev, const char *name)
{
        int i;

        if (cp->allprops || !dev[0])
            return (0);
        for (i = 0; i < cp->nprops; i++)
        {
            Property *pp = &cp->props[i];
            if (!strcmp (pp->dev, dev) && (!pp->name[0] || !strcmp(pp->name, name)))
                return (0);
        }
        return (-1);
}

/* add the given device and property to the devs[] list of client if new.
 */
static void
addClDevice (ClInfo *cp, const char *dev, const char *name, int isblob)
{
        Property *pp;
        char *ip;
        int i=0;

        if (isblob)
        {
            for (i = 0; i < cp->nprops; i++)
            {
                Property *pp = &cp->props[i];
                if (!strcmp (pp->dev, dev) && (!pp->name[0] || !strcmp(pp->name, name)))
                    return;
            }
        }
        /* no dups */
        else if (!findClDevice (cp, dev, name))
            return;

        /* add */
        cp->props = (Property *) realloc (cp->props,
                                            (cp->nprops+1)*sizeof(Property));
        pp = &cp->props[cp->nprops++];

        /*ip = pp->dev;
        strncpy (ip, dev, MAXINDIDEVICE-1);
        ip[MAXINDIDEVICE-1] = '\0';

        ip = pp->name;
        strncpy (ip, name, MAXINDINAME-1);
        ip[MAXINDINAME-1] = '\0';*/

        strncpy (pp->dev, dev, MAXINDIDEVICE);
        strncpy (pp->name, name, MAXINDINAME);
        pp->blob = B_NEVER;
}


/* block to accept a new client arriving on lsocket.
 * return private nonblocking socket or exit.
 */
static int
newClSocket ()
{
        struct sockaddr_in cli_socket;
        socklen_t cli_len;
        int cli_fd;

        /* get a private connection to new client */
        cli_len = sizeof(cli_socket);
        cli_fd = accept (lsocket, (struct sockaddr *)&cli_socket, &cli_len);
        if(cli_fd < 0) {
            fprintf (stderr, "accept: %s\n", strerror(errno));
            Bye();
        }

        /* ok */
        return (cli_fd);
}

/* convert the string value of enableBLOB to our B_ state value.
 * no change if unrecognized
 */
static void
crackBLOB (const char *enableBLOB, BLOBHandling *bp)
{
        if (!strcmp (enableBLOB, "Also"))
            *bp = B_ALSO;
        else if (!strcmp (enableBLOB, "Only"))
            *bp = B_ONLY;
        else if (!strcmp (enableBLOB, "Never"))
            *bp = B_NEVER;
}

/* Update the client property BLOB handling policy */
static void crackBLOBHandling(const char *dev, const char *name, const char *enableBLOB, ClInfo *cp)
{
    int i=0;

    /* If we have EnableBLOB with property name, we add it to Client device list */
    if (name[0])
        addClDevice (cp, dev, name, 1);
    else
    /* Otherwise, we set the whole client blob handling to what's passed (enableBLOB) */
        crackBLOB(enableBLOB, &cp->blob);

    /* If whole client blob handling policy was updated, we need to pass that also to all children
       and if the request was for a specific property, then we apply the policy to it */
    for (i = 0; i < cp->nprops; i++)
    {
        Property *pp = &cp->props[i];
        if (!name[0])           
            crackBLOB(enableBLOB, &pp->blob);
        else if (!strcmp (pp->dev, dev) && (!strcmp(pp->name, name)))
        {
            crackBLOB(enableBLOB, &pp->blob);
            return;
        }
    }
}

/* print key attributes and values of the given xml to stderr.
 */
static void
traceMsg (XMLEle *root)
{
        static const char *prtags[] = {
            "defNumber", "oneNumber",
            "defText",   "oneText",
            "defSwitch", "oneSwitch",
            "defLight",  "oneLight",
        };
        XMLEle *e;
        const char *msg, *perm, *pcd;
        unsigned int i;

        /* print tag header */
        fprintf (stderr, "%s %s %s %s", tagXMLEle(root),
                                                findXMLAttValu(root,"device"),
                                                findXMLAttValu(root,"name"),
                                                findXMLAttValu(root,"state"));
        pcd = pcdataXMLEle (root);
        if (pcd[0])
            fprintf (stderr, " %s", pcd);
        perm = findXMLAttValu(root,"perm");
        if (perm[0])
            fprintf (stderr, " %s", perm);
        msg = findXMLAttValu(root,"message");
        if (msg[0])
            fprintf (stderr, " '%s'", msg);

        /* print each array value */
        for (e = nextXMLEle(root,1); e; e = nextXMLEle(root,0))
            for (i = 0; i < sizeof(prtags)/sizeof(prtags[0]); i++)
                if (strcmp (prtags[i], tagXMLEle(e)) == 0)
                    fprintf (stderr, "\n %10s='%s'", findXMLAttValu(e,"name"),
                                                            pcdataXMLEle (e));

        fprintf (stderr, "\n");
}

/* fill s with current UT string.
 * if no s, use a static buffer
 * return s or buffer.
 * N.B. if use our buffer, be sure to use before calling again
 */
static char *
indi_tstamp (char *s)
{
        static char sbuf[64];
        struct tm *tp;
        time_t t;

        time (&t);
        tp = gmtime (&t);
        if (!s)
            s = sbuf;
        strftime (s, sizeof(sbuf), "%Y-%m-%dT%H:%M:%S", tp);
        return (s);
}

/* log message in root known to be from device dev to ldir, if any.
 */
static void
logDMsg (XMLEle *root, const char *dev)
{
        char stamp[64];
        char logfn[1024];
        const char *ts, *ms;
        FILE *fp;

        /* get message, if any */
        ms = findXMLAttValu (root, "message");
        if (!ms[0])
            return;

        /* get timestamp now if not provided */
        ts = findXMLAttValu (root, "timestamp");
        if (!ts[0])
        {
            indi_tstamp (stamp);
            ts = stamp;
        }

        /* append to log file, name is date portion of time stamp */
        sprintf (logfn, "%s/%.10s.islog", ldir, ts);
        fp = fopen (logfn, "a");
        if (!fp)
            return;     /* oh well */
        fprintf (fp, "%s: %s: %s\n", ts, dev, ms);
        fclose (fp);
}

/* log when then exit */
static void
Bye()
{
        fprintf (stderr, "%s: good bye\n", indi_tstamp(NULL));
        exit(1);
}