/*
 * virsh.c: a Xen shell used to exercise the libvir API
 *
 * Copyright (C) 2005 Red Hat, Inc.
 *
 * See COPYING.LIB for the License of this software
 *
 * Daniel Veillard <veillard@redhat.com>
 */

#define _GNU_SOURCE    /* isblank() */

#include "libvir.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <getopt.h>
#include <sys/types.h>
#include <ctype.h>

#include <readline/readline.h>
#include <readline/history.h>

#include "config.h"

static char *progname;

#ifndef TRUE
#define TRUE 1
#define FALSE 0
#endif

#define VSH_PROMPT_RW    "virsh # "
#define VSH_PROMPT_RO    "virsh > "

#define GETTIMEOFDAY(T) gettimeofday(T, NULL)
#define DIFF_MSEC(T, U) \
        ((((int) ((T)->tv_sec - (U)->tv_sec)) * 1000000.0 + \
          ((int) ((T)->tv_usec - (U)->tv_usec))) / 1000.0)

typedef enum {
    VSH_MESG,        /* standard output */
    VSH_HEADER,      /* header for standard output */
    VSH_FOOTER,      /* timing, last command state, or whatever */
    VSH_DEBUG1,      /* debugN where 'N' = level */
    VSH_DEBUG2,
    VSH_DEBUG3,
    VSH_DEBUG4,
    VSH_DEBUG5
} vshOutType;

/*
 * virsh command line grammar:
 *
 *    command_line    =     <command>\n | <command>; <command>; ...
 *
 *    command         =    <keyword> <option> <data>
 *
 *    option          =     <bool_option> | <int_option> | <string_option>
 *    data            =     <string>
 *
 *    bool_option     =     --optionname
 *    int_option      =     --optionname <number>
 *    string_option   =     --optionname <string>
 *        
 *     keyword        =     [a-zA-Z]
 *     number         =     [0-9]+
 *     string         =     [^[:blank:]] | "[[:alnum:]]"$
 *
 *  Note: only one <data> token per command is supported. It means:
 *        "command aaa bbb" is unsupported and you have to use any option, like:
 *        "command --aaa <data> bbb" or whatever.
 */

/*
 * vshCmdOptType - command option type 
 */   
typedef enum {
    VSH_OT_NONE = 0,   /* none */
    VSH_OT_BOOL,       /* boolean option */
    VSH_OT_STRING,     /* string option */
    VSH_OT_INT,        /* int option */
    VSH_OT_DATA        /* string data (as non-option) */
} vshCmdOptType;

/*
 * Command Option Flags
 */
#define VSH_OFLAG_NONE    0        /* without flags */
#define VSH_OFLAG_REQ    (1 << 1)    /* option required */

/* dummy */
typedef struct __vshControl vshControl;
typedef struct __vshCmd vshCmd;

/*
 * vshCmdInfo -- information about command
 */
typedef struct  {
    char    *name;     /* name of information */
    char    *data;     /* information */
} vshCmdInfo;

/*
 * vshCmdOptDef - command option definition
 */
typedef struct  {
    char             *name;     /* the name of option */
    vshCmdOptType    type;      /* option type */
    int              flag;      /* flags */
    char             *help;     /* help string */
} vshCmdOptDef;

/*
 * vshCmdOpt - command options
 */
typedef struct vshCmdOpt {
    vshCmdOptDef     *def;      /* pointer to relevant option */
    char             *data;     /* allocated data */
    struct vshCmdOpt *next;    
} vshCmdOpt;

/*
 * vshCmdDef - command definition
 */
typedef struct  {
    char             *name;
    int              (*handler)(vshControl *, vshCmd *);    /* command handler */
    vshCmdOptDef     *opts;     /* definition of command options */
    vshCmdInfo       *info;     /* details about command */
} vshCmdDef;

/*
 * vshCmd - parsed command
 */
typedef struct __vshCmd {
    vshCmdDef        *def;      /* command definition */
    vshCmdOpt        *opts;     /* list of command arguments */
    struct __vshCmd  *next;     /* next command */
} __vshCmd;

/*
 * vshControl
 */
typedef struct __vshControl {
    virConnectPtr   conn;       /* connection to hypervisor */
    vshCmd          *cmd;       /* the current command */
    char            *cmdstr;    /* string with command */
    uid_t           uid;        /* process owner */
    int             imode;      /* interactive mode? */
    int             quiet;      /* quiet mode */
    int             debug;      /* print debug messages? */
    int             timing;     /* print timing info? */
} __vshControl;


static vshCmdDef commands[];

static void vshError(vshControl *ctl, int doexit, char *format, ...);
static int vshInit(vshControl *ctl);
static int vshDeinit(vshControl *ctl);
static void vshUsage(vshControl *ctl, char *cmdname);

static int vshParseArgv(vshControl *ctl, int argc, char **argv);

static char *vshCmddefGetInfo(vshCmdDef *cmd, char *info);
static vshCmdDef *vshCmddefSearch(char *cmdname);
static int vshCmddefHelp(vshControl *ctl, char *name, int withprog);

static vshCmdOpt *vshCommandOpt(vshCmd *cmd, char *name);
static int vshCommandOptInt(vshCmd *cmd, char *name, int *found);
static char *vshCommandOptString(vshCmd *cmd, char *name, int *found);
static int vshCommandOptBool(vshCmd *cmd, char *name);

static void vshPrint(vshControl *ctl, vshOutType out, char *format, ...);

static char *vshDomainStateToString(int state);
static int vshConnectionUsability(vshControl *ctl, virConnectPtr conn, int showerror);

/* ---------------
 * Commands
 * ---------------
 */

/*
 * "help" command 
 */
static vshCmdInfo info_help[] = {
    { "syntax",   "help [<command>]" },
    { "help",     "print help" },
    { "desc",     "Prints global help or command specific help." },
    { "version",  "Prints versionning informations." },
    { NULL, NULL }
};

static vshCmdOptDef opts_help[] = {
    { "command", VSH_OT_DATA, 0, "name of command" },
        { NULL, 0, 0, NULL }
};

static int
cmdHelp(vshControl *ctl, vshCmd *cmd) {
    char *cmdname = vshCommandOptString(cmd, "command", NULL);

    if (!cmdname) {
        vshCmdDef *def;
        
        vshPrint(ctl, VSH_HEADER, "Commands:\n\n");
        for(def = commands; def->name; def++)
            vshPrint(ctl, VSH_MESG, "    %-15s %s\n", def->name, 
                    vshCmddefGetInfo(def, "help"));
        return TRUE;
    }
    return vshCmddefHelp(ctl, cmdname, FALSE);
}

/*
 * "connect" command 
 */
static vshCmdInfo info_connect[] = {
    { "syntax",   "connect [--readonly]" },
    { "help",     "(re)connect to hypervisor" },
    { "desc",     "Connect to local hypervisor. This is build-in command after shell start up." },
    { NULL, NULL }
};

static vshCmdOptDef opts_connect[] = {
    { "readonly", VSH_OT_BOOL, 0, "read-only connection" },
        { NULL, 0, 0, NULL }
};

static int
cmdConnect(vshControl *ctl, vshCmd *cmd) {
    int ro = vshCommandOptBool(cmd, "readonly");
    
    if (ctl->conn) {
        if (virConnectClose(ctl->conn)!=0) {
            vshError(ctl, FALSE, "failed to disconnect from the hypervisor");
            return FALSE;
        }
        ctl->conn = NULL;
    }
    if (!ro)
        ctl->conn = virConnectOpen(NULL);
    else
        ctl->conn = virConnectOpenReadOnly(NULL);

    if (!ctl->conn)
        vshError(ctl, FALSE, "failed to connect to the hypervisor");
    
    return ctl->conn ? TRUE : FALSE;
}

/*
 * "list" command
 */
static vshCmdInfo info_list[] = {
    { "syntax",   "list" },
    { "help",     "list domains" },
    { "desc",     "Returns list of domains." },
    { NULL, NULL }
};



static int
cmdList(vshControl *ctl, vshCmd *cmd) {
    int *ids, maxid, i;

    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;
    
    maxid = virConnectNumOfDomains(ctl->conn);
    if (maxid <= 0) {
        /* strange, there should be at least dom0... */
        vshError(ctl, FALSE, "failed to list active domains.");
        return FALSE;
    }
    ids = malloc(sizeof(int) * maxid);
    virConnectListDomains(ctl->conn, &ids[0], maxid);
    
    vshPrint(ctl, VSH_HEADER, "%3s %-20s %s\n", "Id", "Name", "State");
    vshPrint(ctl, VSH_HEADER, "----------------------------------\n");
    
    for(i=0; i < maxid; i++) {
        int ret;
        virDomainInfo info;
        virDomainPtr dom = virDomainLookupByID(ctl->conn, ids[i]);
        
         /* this kind of work with domains is not atomic operation */
        if (!dom)
            continue;
        ret = virDomainGetInfo(dom, &info);
        
        vshPrint(ctl, VSH_MESG, "%3d %-20s %s\n", 
                virDomainGetID(dom), 
                virDomainGetName(dom),
                ret < 0 ? "no state" : vshDomainStateToString(info.state));
        /*TODO: virDomainFree(dom); */
    }
    free(ids);
    return TRUE;
}

/*
 * "dstate" command
 */
static vshCmdInfo info_dstate[] = {
    { "syntax",  "dstate [--id <number> | --name <string> ]" },
    { "help",    "domain state" },
    { "desc",    "Returns state about the domain." },
    { NULL, NULL }
};

static vshCmdOptDef opts_dstate[] = {
    { "name",    VSH_OT_STRING, 0, "domain name" },
    { "id",      VSH_OT_INT,    0, "domain id" },
        { NULL, 0, 0, NULL }
};

static int
cmdDstate(vshControl *ctl, vshCmd *cmd) {
    virDomainInfo info;
    virDomainPtr dom;
    int found, ret = TRUE;
    char *name = vshCommandOptString(cmd, "name", NULL);
    int id = vshCommandOptInt(cmd, "id", &found);
    
    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;

    if (found) {
        if (!(dom = virDomainLookupByID(ctl->conn, id)))
            vshError(ctl, FALSE, "failed to get domain '%d'", id);
    } else {
        if (!(dom = virDomainLookupByName(ctl->conn, name)))
            vshError(ctl, FALSE, "failed to get domain '%s'", name);
    }

    if (!dom)
        return FALSE;
    
    if (virDomainGetInfo(dom, &info)==0)
        vshPrint(ctl, VSH_MESG, "%s\n", vshDomainStateToString(info.state));
    else
        ret = FALSE;
        
    /*TODO: virDomainFree(dom); */
    return ret;
}

/*
 * "dinfo" command
 */
static vshCmdInfo info_dinfo[] = {
    { "syntax",   "dinfo [--id <number> | --name <string> ]" },
    { "help",     "domain information" },
    { "desc",     "Returns basic information about the domain." },
    { NULL, NULL }
};

static vshCmdOptDef opts_dinfo[] = {
    { "name",      VSH_OT_STRING, 0, "domain name" },
    { "id",        VSH_OT_INT,    0, "domain id" },
        { NULL, 0, 0, NULL }
};

static int
cmdDinfo(vshControl *ctl, vshCmd *cmd) {
    virDomainInfo info;
    virDomainPtr dom;
    int found, ret = TRUE;
    char *name = vshCommandOptString(cmd, "name", NULL);
    int id = vshCommandOptInt(cmd, "id", &found);
    
    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;

    if (found) {
        if (!(dom = virDomainLookupByID(ctl->conn, id)))
            vshError(ctl, FALSE, "failed to get domain '%d'", id);
    } else {
        if (!(dom = virDomainLookupByName(ctl->conn, name)))
            vshError(ctl, FALSE, "failed to get domain '%s'", name);
    }
    
    if (!dom)
        return FALSE;
    
    if (virDomainGetInfo(dom, &info)==0) {
        vshPrint(ctl, VSH_MESG, "%-15s %d\n", "Id:", 
                virDomainGetID(dom));
        vshPrint(ctl, VSH_MESG, "%-15s %s\n", "Name:", 
                virDomainGetName(dom));
        vshPrint(ctl, VSH_MESG, "%-15s %s\n", "State:",    
                vshDomainStateToString(info.state));
        vshPrint(ctl, VSH_MESG, "%-15s %d\n", "CPU(s):",
                info.nrVirtCpu);
        
           if (info.cpuTime != 0) 
           {
               float cpuUsed = info.cpuTime;
               cpuUsed /= 1000000000;
            
                vshPrint(ctl, VSH_MESG, "%-15s %.1fs\n", "CPU time:", cpuUsed);
        }
           
        vshPrint(ctl, VSH_MESG, "%-15s %lu kB\n", "Max memory:",
                info.maxMem);
        vshPrint(ctl, VSH_MESG, "%-15s %lu kB\n", "Used memory:",
                info.memory);
        
    } else {
        ret = FALSE;
    }
        
    /*TODO: virDomainFree(dom); */
    return ret;
}

/*
 * "nameof" command
 */
static vshCmdInfo info_nameof[] = {
    { "syntax",   "nameof <id>" },
    { "help",     "convert domain Id to domain name" },
    { NULL, NULL }
};

static vshCmdOptDef opts_nameof[] = {
    { "id",        VSH_OT_DATA,  0, "domain Id" },
        { NULL, 0, 0, NULL }
};

static int
cmdNameof(vshControl *ctl, vshCmd *cmd) {
    int found;
    int id = vshCommandOptInt(cmd, "id", &found);
    virDomainPtr dom;

    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;
    if (!found)
        return FALSE;
    
    dom = virDomainLookupByID(ctl->conn, id);
    if (dom) {
        vshPrint(ctl, VSH_MESG, "%s\n", virDomainGetName(dom));
        /*TODO: virDomainFree(dom); */
    } else {
        vshError(ctl, FALSE, "failed to get domain '%d'", id);
        return FALSE;
    }
    return TRUE;
}

/*
 * "idof" command
 */
static vshCmdInfo info_idof[] = {
    { "syntax",   "idof <name>" },
    { "help",     "convert domain name to domain Id" },
    { NULL, NULL }
};

static vshCmdOptDef opts_idof[] = {
    { "name",     VSH_OT_DATA,   0, "domain name" },
        { NULL, 0, 0, NULL }
};

static int
cmdIdof(vshControl *ctl, vshCmd *cmd) {
    char *name = vshCommandOptString(cmd, "name", NULL);
    virDomainPtr dom;

    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;
    if (!name)
        return FALSE;
    
    dom = virDomainLookupByName(ctl->conn, name);
    if (dom) {
        vshPrint(ctl, VSH_MESG, "%s\n", virDomainGetID(dom));
        /*TODO: virDomainFree(dom); */
    } else {
        vshError(ctl, FALSE, "failed to get domain '%s'", name);
        return FALSE;
    }
    return TRUE;
}

/*
 * "version" command
 */
static vshCmdInfo info_version[] = {
    { "syntax",   "version" },
    { "help",     "show versions" },
    { "desc",     "Display the version informations available" },
    { NULL, NULL }
};


static int
cmdVersion(vshControl *ctl, vshCmd *cmd) {
    unsigned long hvVersion;
    const char *hvType;

    if (!vshConnectionUsability(ctl, ctl->conn, TRUE))
        return FALSE;
    
    hvType = virConnectGetType(ctl->conn);
    if (hvType == NULL) {
        vshError(ctl, FALSE, "Failed to get hypervisor type\n");
        return FALSE;
    }

    hvVersion =  virConnectGetVersion(ctl->conn);
    if (hvVersion < 0) {
        vshError(ctl, FALSE, "failed get hypervisor version");
        return FALSE;
    }
    if (hvVersion == 0) {
        vshPrint(ctl, VSH_MESG,
                 "Cannot extract running %s hypervisor version\n",
                 hvType);
    } else {
        unsigned int major = hvVersion / 1000000;
        unsigned int minor;
        unsigned int rel;

        hvVersion %= 1000000;
        minor = hvVersion / 1000000;
        rel = hvVersion % 1000000;

        vshPrint(ctl, VSH_MESG, "Running hypervisor: %s %d.%d.%d\n", hvType,
                 major, minor, rel);
    }
    return TRUE;
}

/*
 * "quit" command
 */
static vshCmdInfo info_quit[] = {
    { "syntax",   "quit" },
    { "help",     "quit this interactive terminal" },
    { NULL, NULL }
};

static int
cmdQuit(vshControl *ctl, vshCmd *cmd) {
    ctl->imode = FALSE;
    return TRUE;
}

/*
 * Commands
 */
static vshCmdDef commands[] = {
    { "connect",    cmdConnect,    opts_connect,   info_connect },
    { "dinfo",      cmdDinfo,      opts_dinfo,     info_dinfo },
    { "dstate",     cmdDstate,     opts_dstate,    info_dstate },
    { "help",       cmdHelp,       opts_help,      info_help },
    { "idof",       cmdIdof,       opts_idof,      info_idof },
    { "list",       cmdList,       NULL,           info_list },
    { "nameof",     cmdNameof,     opts_nameof,    info_nameof },
    { "version",    cmdVersion,    NULL,           info_version },
    { "quit",       cmdQuit,       NULL,           info_quit },
    { NULL, NULL, NULL, NULL }
};

/* ---------------
 * Utils for work with command definition
 * ---------------
 */
static char *
vshCmddefGetInfo(vshCmdDef *cmd, char *name) {
    vshCmdInfo *info;
    
    for (info = cmd->info; info && info->name; info++) {
        if (strcmp(info->name, name)==0)
            return info->data;
    }
    return NULL;
}

static vshCmdOptDef *
vshCmddefGetOption(vshCmdDef *cmd, char *name) {
    vshCmdOptDef *opt;
    
    for (opt = cmd->opts; opt && opt->name; opt++)
        if (strcmp(opt->name, name)==0)
            return opt;
    return NULL;
}

static vshCmdOptDef *
vshCmddefGetData(vshCmdDef *cmd) {
    vshCmdOptDef *opt;

    for (opt = cmd->opts; opt && opt->name; opt++)
        if (opt->type==VSH_OT_DATA)
            return opt;
    return NULL;
}

static vshCmdDef *
vshCmddefSearch(char *cmdname) {
    vshCmdDef *c;
    
    for (c = commands; c->name; c++)
        if (strcmp(c->name, cmdname)==0)
            return c;
    return NULL;
}

static int
vshCmddefHelp(vshControl *ctl, char *cmdname, int withprog) {
    vshCmdDef *def = vshCmddefSearch(cmdname);
    
    if (!def) {
         vshError(ctl, FALSE, "command '%s' doesn't exist", cmdname);
         return FALSE;
    } else {    
        vshCmdOptDef *opt;
        char *desc = vshCmddefGetInfo(def, "desc");
        char *help = vshCmddefGetInfo(def, "help");
        char *syntax = vshCmddefGetInfo(def, "syntax");

        fputs("  NAME\n", stdout);
        fprintf(stdout, "    %s - %s\n", def->name,  help);
        
        if (syntax) {
            fputs("\n  SYNOPSIS\n", stdout);
            if (!withprog)
                fprintf(stdout, "    %s\n", syntax);
            else
                fprintf(stdout, "    %s %s\n", progname, syntax);
        }
        if (desc) {
            fputs("\n  DESCRIPTION\n", stdout);
            fprintf(stdout, "    %s\n", desc);
        }
        if (def->opts) {
            fputs("\n  OPTIONS\n", stdout);
            for (opt=def->opts; opt->name; opt++) {
                char buf[256];
                
                if (opt->type==VSH_OT_BOOL)
                    snprintf(buf, sizeof(buf), "--%s", opt->name);
                else if (opt->type==VSH_OT_INT)
                    snprintf(buf, sizeof(buf), "--%s <number>", opt->name);
                else if (opt->type==VSH_OT_STRING)
                    snprintf(buf, sizeof(buf), "--%s <string>", opt->name);
                else if (opt->type==VSH_OT_DATA)
                    snprintf(buf, sizeof(buf), "<%s>", opt->name);
                
                fprintf(stdout, "    %-15s  %s\n", buf, opt->help);
            }    
        }
        fputc('\n', stdout);
    }
    return TRUE;
}

/* ---------------
 * Utils for work with runtime commands data
 * ---------------
 */
static void     
vshCommandOptFree(vshCmdOpt *arg) {
    vshCmdOpt *a = arg;

    while(a) {
        vshCmdOpt *tmp = a;
        a = a->next;

        if (tmp->data)
            free(tmp->data);
        free(tmp);
    }
}

static void
vshCommandFree(vshCmd *cmd) {
    vshCmd *c = cmd;

    while(c) {
        vshCmd *tmp = c;
        c = c->next;

        if (tmp->opts)
            vshCommandOptFree(tmp->opts);
        free(tmp);
    }
}

/*
 * Returns option by name
 */
static vshCmdOpt *
vshCommandOpt(vshCmd *cmd, char *name) {
    vshCmdOpt *opt = cmd->opts;
    
    while(opt) {
        if (opt->def && strcmp(opt->def->name, name)==0)
            return opt;
        opt = opt->next;
    }
    return NULL;
}

/*
 * Returns option as INT
 */
static int
vshCommandOptInt(vshCmd *cmd, char *name, int *found) {
    vshCmdOpt *arg = vshCommandOpt(cmd, name);
    int res = 0;
    
    if (arg)
        res = atoi(arg->data);
    if (found)
        *found = arg ? TRUE : FALSE;
    return res;
}

/*
 * Returns option as STRING
 */
static char *
vshCommandOptString(vshCmd *cmd, char *name, int *found) {
    vshCmdOpt *arg = vshCommandOpt(cmd, name);
    if (found)
        *found = arg ? TRUE : FALSE;
    return arg ? arg->data : NULL;
}

/*
 * Returns TRUE/FALSE if the option exists
 */
static int
vshCommandOptBool(vshCmd *cmd, char *name) {
    return vshCommandOpt(cmd, name) ? TRUE : FALSE;
}

/*
 * Executes command(s) and returns return code from last command
 */
static int
vshCommandRun(vshControl *ctl, vshCmd *cmd) {
    int ret = TRUE;
    
    while(cmd) {
        struct timeval before, after;
        
        if (ctl->timing)
            GETTIMEOFDAY(&before);
        
        ret = cmd->def->handler(ctl, cmd);

        if (ctl->timing)
            GETTIMEOFDAY(&after);
        
        if (strcmp(cmd->def->name, "quit")==0) /* hack ... */
            return ret;

        if (ctl->timing)
            vshPrint(ctl, VSH_MESG, "\n(Time: %.3f ms)\n\n", DIFF_MSEC(&after, &before));
        else     
            vshPrint(ctl, VSH_FOOTER, "\n");
        cmd = cmd->next;
    }
    return ret;
}

/* ---------------
 * Command string parsing
 * ---------------
 */
#define VSH_TK_ERROR    -1
#define VSH_TK_NONE    0
#define VSH_TK_OPTION    1
#define VSH_TK_DATA    2
#define VSH_TK_END    3

static int 
vshCommandGetToken(vshControl *ctl, char *str, char **end, char **res) {
    int tk = VSH_TK_NONE;
    int quote = FALSE;
    int sz = 0;
    char *p = str;
    char *tkstr = NULL;
    
    *end = NULL;
    
    while(p && *p && isblank((unsigned char) *p)) 
        p++;
    
    if (p==NULL || *p=='\0')
        return VSH_TK_END;
     if (*p==';') {
        *end = ++p;        /* = \0 or begi of next command */
        return VSH_TK_END;
    }
    while(*p) {
        /* end of token is blank space or ';' */
        if ((quote==FALSE && isblank((unsigned char) *p)) || *p==';')
            break;

        if (tk==VSH_TK_NONE) {
            if (*p=='-' && *(p+1)=='-' && *(p+2) && isalnum((unsigned char) *(p+2))) {
                tk = VSH_TK_OPTION;
                p+=2;
            } else {
                tk = VSH_TK_DATA;
                if (*p=='"') {
                           quote = TRUE;
                    p++;
                } else {
                    quote = FALSE;
                }
            }
            tkstr = p;    /* begin of token */
        } else if (quote && *p=='"') {
            quote = FALSE;
            p++;
            break;        /* end of "..." token */
        }
        p++;
        sz++;
    }
    if (quote) {
        vshError(ctl, FALSE, "missing \"");
        return VSH_TK_ERROR;
    }
    if (tkstr==NULL || *tkstr=='\0' || p==NULL)
        return VSH_TK_END;
    if (sz==0)
        return VSH_TK_END;
    
    *res = malloc(sz+1);
    memcpy(*res, tkstr, sz);
    *(*res+sz) = '\0';

    *end = p;
    return tk;
}

static int
vshCommandParse(vshControl *ctl, char *cmdstr) {
    char *str;
    char *tkdata = NULL;
    vshCmd *clast = NULL;
    vshCmdOpt *first = NULL;
    
    if (ctl->cmd) {
        vshCommandFree(ctl->cmd);
        ctl->cmd = NULL;
    }
    
    if (cmdstr==NULL || *cmdstr=='\0')
        return FALSE;
    
    str = cmdstr;
    while(str && *str) 
    {
        vshCmdOpt *last = NULL;
        vshCmdDef *cmd = NULL;
        int tk = VSH_TK_NONE;
        
        first = NULL;
        
        while (tk!=VSH_TK_END) {
            char *end = NULL;
            vshCmdOptDef *opt = NULL;
    
            tkdata = NULL;
            
            /* get token */
            tk = vshCommandGetToken(ctl, str, &end, &tkdata);
            
            str = end;
            
            if (tk==VSH_TK_END)
                break;
            if (tk==VSH_TK_ERROR)
                goto syntaxError;
            
            if (cmd==NULL) {
                /* first token must be command name */
                if (tk!=VSH_TK_DATA) {
                    vshError(ctl, FALSE, 
                        "unexpected token (command name): '%s'", 
                        tkdata);
                    goto syntaxError;
                }
                if (!(cmd = vshCmddefSearch(tkdata))) {
                    vshError(ctl, FALSE,
                        "unknown command: '%s'", tkdata);
                    goto syntaxError;  /* ... or ignore this command only? */
                }
                free(tkdata);
            } else if (tk==VSH_TK_OPTION) {
                if (!(opt = vshCmddefGetOption(cmd, tkdata))) {
                    vshError(ctl, FALSE,
                        "command '%s' doesn't support option --%s",
                        cmd->name, tkdata);
                    goto syntaxError;
                }
                free(tkdata);        /* option name */
                tkdata = NULL;

                if (opt->type != VSH_OT_BOOL) {
                    /* option data */
                    tk = vshCommandGetToken(ctl, str, &end, &tkdata);
                    str = end;    
                    if (tk==VSH_TK_ERROR)
                        goto syntaxError;
                    if (tk!=VSH_TK_DATA) {
                        vshError(ctl, FALSE,
                            "expected syntax: --%s <%s>", 
                            opt->name, 
                            opt->type==VSH_OT_INT ? "number" : "string");
                        goto syntaxError;
                    }
                }
            } else if (tk==VSH_TK_DATA) {
                if (!(opt = vshCmddefGetData(cmd))) {
                    vshError(ctl, FALSE,
                        "unexpected data '%s'",
                               tkdata);
                    goto syntaxError;
                }
            }
            if (opt) {
                /* save option */
                vshCmdOpt *arg = malloc(sizeof(vshCmdOpt));
                
                arg->def = opt;
                arg->data = tkdata;
                arg->next = NULL;
                tkdata = NULL;
                
                if (!first)
                    first = arg;
                if (last)
                    last->next = arg;
                last = arg;
                
                vshPrint(ctl, VSH_DEBUG4, "%s: %s(%s): %s\n",
                    cmd->name,
                    opt->name,
                    tk==VSH_TK_OPTION ? "OPTION" : "DATA",
                    arg->data);
            }
            if (!str)
                break;
        }
        
        /* commad parsed -- allocate new struct for the command */
        if (cmd) {
            vshCmd *c = malloc(sizeof(vshCmd));    
            c->opts = first;
            c->def = cmd;
            c->next = NULL;

            if (!ctl->cmd)
                ctl->cmd = c;
            if (clast)
                clast->next = c;
            clast = c;
        }
    }
    
    return TRUE;

syntaxError:
    if (ctl->cmd)
        vshCommandFree(ctl->cmd);
    if (first)
        vshCommandOptFree(first);
    if (tkdata)
        free(tkdata);
    return FALSE;    
}


/* ---------------
 * Misc utils  
 * ---------------
 */
static char *
vshDomainStateToString(int state) {
    switch (state) {
        case VIR_DOMAIN_RUNNING:
                return "running ";
        case VIR_DOMAIN_BLOCKED:
            return "blocked ";
        case VIR_DOMAIN_PAUSED:
            return "paused ";
        case VIR_DOMAIN_SHUTDOWN:
            return "in shutdown";
        case VIR_DOMAIN_SHUTOFF:
            return "shut off";
        default:
            return "no state";    /* = dom0 state */
    }
    return NULL;
}

static int
vshConnectionUsability(vshControl *ctl, virConnectPtr conn, int showerror) {
    /* TODO: use something like virConnectionState() to 
     *       check usability of the connection 
     */
    if (!conn) {
        if (showerror)
            vshError(ctl, FALSE, "no valid connection.");
        return FALSE;
    }
    return TRUE;
}

static int
vshWantedDebug(vshOutType type, int mode) {
    switch(type) {
        case VSH_DEBUG5:
            if (mode < 5)
                return FALSE;
            return TRUE;
        case VSH_DEBUG4:
            if (mode < 4)
                return FALSE;
            return TRUE;
        case VSH_DEBUG3:
            if (mode < 3)
                return FALSE;
            return TRUE;
        case VSH_DEBUG2:
            if (mode < 2)
                return FALSE;
            return TRUE;
        case VSH_DEBUG1:
            if (mode < 1)
                return FALSE;
            return TRUE;
        default:
            /* it's right, all others types have to pass */
            return TRUE;
    }
    return FALSE;
}

static void
vshPrint(vshControl *ctl, vshOutType type, char *format, ...) {
    va_list ap;
    
    if (ctl->quiet==TRUE && (type==VSH_HEADER || type==VSH_FOOTER))
        return;

    if (!vshWantedDebug(type, ctl->debug))
        return;
    
    va_start(ap, format);
    vfprintf(stderr, format, ap);
    va_end(ap);
}

static void
vshError(vshControl *ctl, int doexit, char *format, ...) {
    va_list ap;
    
    if (doexit)
        fprintf(stderr, "%s: error: ", progname);
    else
        fputs("error: ", stderr);
    
    va_start(ap, format);
    vfprintf(stderr, format, ap);
    va_end(ap);

    fputc('\n', stderr);
    
    if (doexit) {
        vshDeinit(ctl);
        exit(EXIT_FAILURE);
    }
}

/*
 * Initialize vistsh
 */
static int
vshInit(vshControl *ctl) {
    if (ctl->conn)
        return FALSE;

    ctl->uid = getuid();
    
    /* basic connection to hypervisor */
    if (ctl->uid == 0)
        ctl->conn = virConnectOpen(NULL);
    else
        ctl->conn = virConnectOpenReadOnly(NULL);
    
    if (!ctl->conn)
        vshError(ctl, TRUE, "failed to connect to the hypervisor");

    return TRUE;
}

/* -----------------
 * Readline stuff
 * -----------------
 */

/* 
 * Generator function for command completion.  STATE lets us
 * know whether to start from scratch; without any state
 * (i.e. STATE == 0), then we start at the top of the list. 
 */
static char *
vshReadlineCommandGenerator(const char *text, int state) {
    static int list_index, len;
    char *name;

    /* If this is a new word to complete, initialize now.  This
     * includes saving the length of TEXT for efficiency, and
     * initializing the index variable to 0. 
     */
    if (!state) {
        list_index = 0;
        len = strlen (text);
    }

    /* Return the next name which partially matches from the
     * command list. 
     */
    while (name = commands[list_index].name) {
        list_index++;
        if (strncmp (name, text, len) == 0)
            return strdup(name);
    }

    /* If no names matched, then return NULL. */
    return NULL;
}

static char *
vshReadlineOptionsGenerator(const char *text, int state) {
    static int list_index, len;
    static vshCmdDef *cmd = NULL;
    char *name;

    if (!state) {
        /* determine command name */
        char *p;
        char *cmdname;

        if (!(p = strchr(rl_line_buffer, ' ')))
            return NULL;

        cmdname = calloc((p - rl_line_buffer)+ 1, 1);
        memcpy(cmdname, rl_line_buffer, p-rl_line_buffer);

        cmd = vshCmddefSearch(cmdname);
        list_index = 0;
        len = strlen (text);
        free(cmdname);
    }

    if (!cmd)
        return NULL;
    
    while (name = cmd->opts[list_index].name) {
        vshCmdOptDef *opt = &cmd->opts[list_index];
        char *res;
        list_index++;
       
        if (cmd->opts[list_index].type == VSH_OT_DATA)
            /* ignore non --option */
            continue;
        
        if (len > 2) {
            if (strncmp (name, text+2, len-2))
                continue;
        }
        res = malloc(strlen(name)+3);
        sprintf(res, "--%s", name);
        return res;
    }

    /* If no names matched, then return NULL. */
    return NULL;
}

static char **
vshReadlineCompletion(const char *text, int start, int end) {
    char **matches = (char **) NULL;

    if (start==0)
        /* command name generator */
        matches = rl_completion_matches (text, vshReadlineCommandGenerator);
    else
        /* commands options */
        matches = rl_completion_matches (text, vshReadlineOptionsGenerator);
    return matches;
}


static void
vshReadlineInit(vshControl *ctl) {
    /* Allow conditional parsing of the ~/.inputrc file. */
    rl_readline_name = "virsh";

    /* Tell the completer that we want a crack first. */
    rl_attempted_completion_function = vshReadlineCompletion;
}

/*
 * Deinitliaze virsh
 */
static int
vshDeinit(vshControl *ctl) {
    if (ctl->conn) {
        if (virConnectClose(ctl->conn)!=0) {
            ctl->conn = NULL; /* prevent recursive call from vshError() */
            vshError(ctl, TRUE, "failed to disconnect from the hypervisor");
        }
    }
    return TRUE;
}
    
/*
 * Print usage
 */
static void
vshUsage(vshControl *ctl, char *cmdname) {
    vshCmdDef *cmd;
    
    /* global help */
    if (!cmdname) {
        fprintf(stdout, "\n%s [options] [commands]\n\n"
                "  options:\n"
                "    -d | --debug <num>      debug level [0-5]\n"
                "    -h | --help             this help\n"
                "    -q | --quiet            quiet mode\n"
                "    -t | --timing           print timing information\n"
                "    -v | --version          program version\n\n"
                "  commands (non interactive mode):\n", progname);
    
        for(cmd = commands; cmd->name; cmd++)
            fprintf(stdout, 
                "    %-15s %s\n", cmd->name, vshCmddefGetInfo(cmd, "help"));
        
        fprintf(stdout, "\n  (specify --help <command> for details about the command)\n\n");
        return;
    }
    if (!vshCmddefHelp(ctl, cmdname, TRUE))
        exit(EXIT_FAILURE);
}

/*
 * argv[]:  virsh [options] [command]
 *
 */
static int
vshParseArgv(vshControl *ctl, int argc, char **argv) {
    char *last = NULL;
    int i, end = 0, help = 0;
    int arg, idx=0;
    struct option opt[] = {
        { "debug",    1, 0, 'd' },
        { "help",     0, 0, 'h' },
        { "quiet",    0, 0, 'q' },
        { "timing",   0, 0, 't' },
        { "version",  0, 0, 'v' },
        {0, 0, 0, 0}
    };         

    
    if (argc < 2)
        return;
    
    /* look for begin of command, for example:
     *   ./virsh --debug 5 -q command --cmdoption
     *                  <--- ^ --->
     *        getopt() stuff | command suff
     */
    for(i=1; i < argc; i++) {
        if (*argv[i] != '-') {
            int valid = FALSE;
            
            /* non "--option" argv, is it command? */
            if (last) {
                struct option *o;
                int sz = strlen(last);
                
                for(o=opt; o->name; o++) {
                    if (sz==2 && *(last+1)==o->val)
                        /* valid virsh short option */
                        valid = TRUE;
                    else if (sz > 2 && strcmp(o->name, last+2)==0)
                        /* valid virsh long option */
                        valid = TRUE;
                }
            }
            if (!valid) {
                end = i;
                break;
            }
        }
        last = argv[i];
    }
    end = end ? : argc;
    
    /* standard (non-command) options */
    while((arg = getopt_long(end, argv, "d:hqtv", opt, &idx)) != -1) {
        switch(arg) {
            case 'd':
                ctl->debug = atoi(optarg);
                break;
            case 'h':
                help = 1;
                break;
            case 'q':
                ctl->quiet = TRUE;
                break;
            case 't':
                ctl->timing = TRUE;
                break;
            case 'v':
                fprintf(stdout, "%s\n", VERSION);
                exit(EXIT_SUCCESS);
            default:
                vshError(ctl, TRUE, "unsupported option '-%c'. See --help.", arg);
                break;
        }
    }

    if (help) {
        /* global or command specific help */
        vshUsage(ctl, argc > end ? argv[end] : NULL);
        exit(EXIT_SUCCESS);
    }    
    
    if (argc > end) {
        /* parse command */
        char *cmdstr;
        int sz=0, i, ret;
        
        ctl->imode = FALSE;
        
        for (i=end; i < argc; i++)
            sz += strlen(argv[i]) + 1;     /* +1 is for blank space between items */

        cmdstr = calloc(sz+1, 1);
        
        for (i=end; i < argc; i++) {
            strncat(cmdstr, argv[i], sz);
            sz -= strlen(argv[i]);
            strncat(cmdstr, " ", sz--);
        }
        vshPrint(ctl, VSH_DEBUG2, "command: \"%s\"\n", cmdstr);
        ret = vshCommandParse(ctl, cmdstr);
        
        free(cmdstr);
        return ret;
    }
    return TRUE;
}

int 
main(int argc, char **argv) {
    vshControl _ctl, *ctl=&_ctl;
    int ret = TRUE;

    if (!(progname=strrchr(argv[0], '/')))
        progname = argv[0];
    else
        progname++;
    
    memset(ctl, 0, sizeof(vshControl));
    ctl->imode = TRUE;    /* default is interactive mode */

    if (!vshParseArgv(ctl, argc, argv))
        exit(EXIT_FAILURE);
        
    if (!vshInit(ctl))
        exit(EXIT_FAILURE);
    
    if (!ctl->imode) {
        ret = vshCommandRun(ctl, ctl->cmd);    
    } else {
        /* interactive mode */
        if (!ctl->quiet) {
            vshPrint(ctl, VSH_MESG, "Welcome to %s, the virtualization interactive terminal.\n\n", 
                        progname);
            vshPrint(ctl, VSH_MESG, "Type:  'help' for help with commands\n"
                                    "       'quit' to quit\n\n");
        }
        vshReadlineInit(ctl);
        do {
            ctl->cmdstr = readline(ctl->uid==0 ? VSH_PROMPT_RW : VSH_PROMPT_RO);
            if (ctl->cmdstr==NULL)
                break;                /* EOF */
            if (*ctl->cmdstr) {
                add_history(ctl->cmdstr);
                if (vshCommandParse(ctl, ctl->cmdstr))
                    vshCommandRun(ctl, ctl->cmd);
            }
            free(ctl->cmdstr);
            ctl->cmdstr = NULL;
        } while(ctl->imode);    

        if (ctl->cmdstr==NULL)
            fputc('\n', stdout);    /* line break after alone prompt */
    }
    
    vshDeinit(ctl);
    exit(ret ? EXIT_SUCCESS : EXIT_FAILURE);
}

/*
 * vim: set tabstop=4:
 * vim: set shiftwidth=4:
 * vim: set expandtab:
 */