lib/gvc/gvplugin.c

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/* $Id$ $Revision$ */
/* vim:set shiftwidth=4 ts=8: */

/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: See CVS logs. Details at http://www.graphviz.org/
 *************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include        <string.h>
#ifdef ENABLE_LTDL
#include        <ltdl.h>
#endif

#include        <agxbuf.h>
#include        "memory.h"
#include        "types.h"
#include        "gvplugin.h"
#include        "gvcjob.h"
#include        "gvcint.h"
#include        "gvcproc.h"
#include        "gvio.h"

#include        "const.h"

#ifndef HAVE_STRCASECMP
extern int strcasecmp(const char *s1, const char *s2);
#endif

#ifdef WIN32
#define strdup(x) _strdup(x)
#endif

/*
 * Define an apis array of name strings using an enumerated api_t as index.
 * The enumerated type is defined gvplugin.h.  The apis array is
 * inititialized here by redefining ELEM and reinvoking APIS.
 */
#define ELEM(x) #x,
static char *api_names[] = { APIS };    /* "render", "layout", ... */
#undef ELEM

/* translate a string api name to its type, or -1 on error */
api_t gvplugin_api(char *str)
{
    int api;

    for (api = 0; api < ARRAY_SIZE(api_names); api++) {
        if (strcmp(str, api_names[api]) == 0)
            return (api_t)api;
    }
    return -1;                  /* invalid api */
}

/* translate api_t into string name, or NULL */
char *gvplugin_api_name(api_t api)
{
    if (api < 0 || api >= ARRAY_SIZE(api_names))
        return NULL;
    return api_names[api];
}

/* install a plugin description into the list of available plugins
 * list is alpha sorted by type (not including :dependency), then
 * quality sorted within the type, then, if qualities are the same,
 * last install wins.
 */
boolean gvplugin_install(GVC_t * gvc, api_t api, const char *typestr,
        int quality, gvplugin_package_t *package,
        gvplugin_installed_t * typeptr)
{
    gvplugin_available_t *plugin, **pnext;
#define TYPSIZ 63
    char *p, pins[TYPSIZ+1], pnxt[TYPSIZ+1];

    if (api < 0)
        return FALSE;

    strncpy(pins, typestr, TYPSIZ);
    if ((p = strchr(pins, ':')))
        *p = '\0';
    
    /* point to the beginning of the linked list of plugins for this api */
    pnext = &(gvc->apis[api]);

    /* keep alpha-sorted and insert new duplicates ahead of old */
    while (*pnext) {
        strncpy(pnxt, (*pnext)->typestr, TYPSIZ);
        if ((p = strchr(pnxt, ':')))
            *p = '\0';
        if (strcmp(pins, pnxt) <= 0)
            break;
        pnext = &((*pnext)->next);
    }

    /* keep quality sorted within type and insert new duplicates ahead of old */
    while (*pnext) {
        strncpy(pnxt, (*pnext)->typestr, TYPSIZ);
        if ((p = strchr(pnxt, ':')))
            *p = '\0';
        if (strcmp(pins, pnxt) != 0)
            break;
        if (quality >= (*pnext)->quality)
            break;
        pnext = &((*pnext)->next);
    }

    plugin = GNEW(gvplugin_available_t);
    plugin->next = *pnext;
    *pnext = plugin;
    plugin->typestr = typestr;
    plugin->quality = quality;
    plugin->package = package;
    plugin->typeptr = typeptr;  /* null if not loaded */

    return TRUE;
}

/* Activate a plugin description in the list of available plugins.
 * This is used when a plugin-library loaded because of demand for
 * one of its plugins. It updates the available plugin data with
 * pointers into the loaded library.
 * NB the quality value is not replaced as it might have been
 * manually changed in the config file.
 */
static boolean gvplugin_activate(GVC_t * gvc, api_t api,
                 const char *typestr, char *name, char *path,
                 gvplugin_installed_t * typeptr)
{
    gvplugin_available_t **pnext;


    if (api < 0)
        return FALSE;

    /* point to the beginning of the linked list of plugins for this api */
    pnext = &(gvc->apis[api]);

    while (*pnext) {
        if ( (strcasecmp(typestr, (*pnext)->typestr) == 0)
          && (strcasecmp(name, (*pnext)->package->name) == 0)
          && ((*pnext)->package->path != 0)
          && (strcasecmp(path, (*pnext)->package->path) == 0)) {
            (*pnext)->typeptr = typeptr;
            return TRUE;
        }
        pnext = &((*pnext)->next);
    }
    return FALSE;
}

gvplugin_library_t *gvplugin_library_load(GVC_t *gvc, char *path)
{
#ifdef ENABLE_LTDL
    lt_dlhandle hndl;
    lt_ptr ptr;
    char *s, *sym;
    int len;
    static char *p;
    static int lenp;
    char *libdir;
    char *suffix = "_LTX_library";

    if (! gvc->common.demand_loading)
        return NULL;

    libdir = gvconfig_libdir(gvc);
    len = strlen(libdir) + 1 + strlen(path) + 1;
    if (len > lenp) {
        lenp = len+20;
        if (p)
            p = grealloc(p, lenp);
        else
            p = gmalloc(lenp);
    }
        
#ifdef WIN32
    if (path[1] == ':') {
#else
    if (path[0] == '/') {
#endif
        strcpy(p, path);
    } else {
        strcpy(p, libdir);
        strcat(p, DIRSEP);
        strcat(p, path);
    }

    if (lt_dlinit()) {
        agerr(AGERR, "failed to init libltdl\n");
        return NULL;
    }
    hndl = lt_dlopen (p);
    if (!hndl) {
        agerr(AGWARN, "Could not load \"%s\" - %s\n", p, (char*)lt_dlerror());
        return NULL;
    }
    if (gvc->common.verbose >= 2)
        fprintf(stderr, "Loading %s\n", p);

        s = strrchr(p, DIRSEP[0]);
    len = strlen(s); 
#if defined(WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
    if (len < strlen("/gvplugin_x")) {
#else
    if (len < strlen("/libgvplugin_x")) {
#endif
        agerr (AGERR,"invalid plugin path \"%s\"\n", p);
        return NULL;
    }
    sym = gmalloc(len + strlen(suffix) + 1);
#if defined(WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
    strcpy(sym, s+1);         /* strip leading "/"  */
#else
    strcpy(sym, s+4);         /* strip leading "/lib" or "/cyg" */
#endif
#if defined(__CYGWIN__) || defined(__MINGW32__)
    s = strchr(sym, '-');     /* strip trailing "-1.dll" */
#else 
    s = strchr(sym, '.');     /* strip trailing ".so.0" or ".dll" or ".sl" */
#endif
    strcpy(s,suffix);         /* append "_LTX_library" */

    ptr = lt_dlsym (hndl, sym);
    if (!ptr) {
        agerr (AGERR,"failed to resolve %s in %s\n", sym, p);
        free(sym);
        return NULL;
    }
    free(sym);
    return (gvplugin_library_t *)(ptr);
#else
    agerr (AGERR,"dynamic loading not available\n");
    return NULL;
#endif
}


/* load a plugin of type=str
        the str can optionally contain one or more ":dependencies" 

        examples:
                png
                png:cairo
        fully qualified:
                png:cairo:cairo
                png:cairo:gd
                png:gd:gd
      
*/
gvplugin_available_t *gvplugin_load(GVC_t * gvc, api_t api, const char *str)
{
    gvplugin_available_t **pnext, *rv;
    gvplugin_library_t *library;
    gvplugin_api_t *apis;
    gvplugin_installed_t *types;
#define TYPBUFSIZ 64
    char reqtyp[TYPBUFSIZ], typ[TYPBUFSIZ];
    char *reqdep, *dep = NULL, *reqpkg;
    int i;
    api_t apidep;

    /* check for valid apis[] index */
    if (api < 0)
        return NULL;

    if (api == API_device
        || api == API_loadimage) /* api dependencies - FIXME - find better way to code these *s */

        apidep = API_render;    
    else
        apidep = api;

    strncpy(reqtyp, str, TYPBUFSIZ-1);
    reqdep = strchr(reqtyp, ':');
    if (reqdep) {
        *reqdep++ = '\0';
        reqpkg = strchr(reqdep, ':');
        if (reqpkg)
            *reqpkg++ = '\0';
    }
    else
        reqpkg = NULL;

    /* iterate the linked list of plugins for this api */
    for (pnext = &(gvc->apis[api]); *pnext; pnext = &((*pnext)->next)) {
        strncpy(typ, (*pnext)->typestr, TYPBUFSIZ-1);
        dep = strchr(typ, ':');
        if (dep) 
            *dep++ = '\0';
        if (strcmp(typ, reqtyp)) 
            continue;  /* types empty or mismatched */
        if (dep && reqdep && strcmp(dep, reqdep))
            continue;  /* dependencies not empty, but mismatched */
        if (! reqpkg || strcmp(reqpkg, (*pnext)->package->name) == 0)
        {
                /* found with no packagename constraints, or with required matching packagname */
    
                if (dep && (apidep != api)) /* load dependency if needed, continue if can't find */
                        if (! (gvplugin_load(gvc, apidep, dep)))
                                continue;
                break;
    }
    }
    rv = *pnext;

    if (rv && rv->typeptr == NULL) {
        library = gvplugin_library_load(gvc, rv->package->path);
        if (library) {

            /* Now activate the library with real type ptrs */
            for (apis = library->apis; (types = apis->types); apis++) {
                for (i = 0; types[i].type; i++) {
                    /* NB. quality is not checked or replaced
                     *   in case user has manually edited quality in config */
                    gvplugin_activate(gvc,
                                apis->api,
                                types[i].type,
                                library->packagename,
                                rv->package->path,
                                &types[i]);
                }
            }
            if (gvc->common.verbose >= 1)
                fprintf(stderr, "Activated plugin library: %s\n",
                        rv->package->path ? rv->package->path : "<builtin>");
        }
    }

    /* one last check for successfull load */
    if (rv && rv->typeptr == NULL)
        rv = NULL;

    if (rv && gvc->common.verbose >= 1)
        fprintf(stderr, "Using %s: %s:%s\n",
                api_names[api],
                rv->typestr,
                rv->package->name
                );

    gvc->api[api] = rv;
    return rv;
}

/* assemble a string list of available plugins 
 * non-re-entrant as character store is shared
 */
char *gvplugin_list(GVC_t * gvc, api_t api, const char *str)
{
    static int first = 1;
    gvplugin_available_t **pnext, **plugin;
    char *bp;
    char *s, *p, *q, *typestr_last;
    boolean new = TRUE;
    static agxbuf xb;

    /* check for valid apis[] index */
    if (api < 0)
        return NULL;

    /* check for valid str */
    if (! str)
        return NULL;

    if (first) {
        agxbinit(&xb, 0, 0);
        first = 0;
    }

    /* does str have a :path modifier? */
    s = strdup(str);
    p = strchr(s, ':');
    if (p)
        *p++ = '\0';

    /* point to the beginning of the linked list of plugins for this api */
    plugin = &(gvc->apis[api]);

    if (p) {    /* if str contains a ':', and if we find a match for the type,
                   then just list the alternative paths for the plugin */
        for (pnext = plugin; *pnext; pnext = &((*pnext)->next)) {
            q = strdup((*pnext)->typestr);
            if ((p = strchr(q, ':')))
                *p++ = '\0';
            /* list only the matching type, or all types if s is an empty string */
            if (!s[0] || strcasecmp(s, q) == 0) {
                /* list each member of the matching type as "type:path" */
                agxbputc(&xb,' '); agxbput(&xb, (*pnext)->typestr);
                agxbputc(&xb,':'); agxbput(&xb, (*pnext)->package->name);
                new = FALSE;
            }
            free(q);
        }
    }
    free(s);
    if (new) {                  /* if the type was not found, or if str without ':',
                                   then just list available types */
        typestr_last = NULL;
        for (pnext = plugin; *pnext; pnext = &((*pnext)->next)) {
            /* list only one instance of type */
            q = strdup((*pnext)->typestr);
            if ((p = strchr(q, ':')))
                *p++ = '\0';
            if (!typestr_last || strcasecmp(typestr_last, q) != 0) {
                /* list it as "type"  i.e. w/o ":path" */
                agxbputc(&xb,' '); agxbput(&xb, q);
                new = FALSE;
            }
            if(!typestr_last)
                free(typestr_last);
            typestr_last = q;
        }
        if(!typestr_last)
            free(typestr_last);
    }
    if (new)
        bp = "";
    else
        bp = agxbuse(&xb);
    return bp;
}

/* gvPluginList:
 * Return list of plugins of type kind.
 * The size of the list is stored in sz.
 * The caller is responsible for freeing the storage. This involves
 * freeing each item, then the list.
 * Returns NULL on error, or if there are no plugins.
 * In the former case, sz is unchanged; in the latter, sz = 0.
 *
 * At present, the str argument is unused, but may be used to modify
 * the search as in gvplugin_list above.
 */
char **gvPluginList(GVC_t * gvc, char* kind, int* sz, const char *str)
{
    int api;
    gvplugin_available_t **pnext, **plugin;
    int cnt = 0;    
    char** list = NULL;
    char *p, *q, *typestr_last;

    if (!kind) return NULL;
    for (api = 0; api < ARRAY_SIZE(api_names); api++) {
        if (!strcasecmp(kind,api_names[api]))
            break;
    }
    if (api == ARRAY_SIZE(api_names)) {
        agerr(AGERR, "unrecognized api name \"%s\"\n", kind);
        return NULL;
    }

    /* point to the beginning of the linked list of plugins for this api */
    plugin = &(gvc->apis[api]);
    typestr_last = NULL;
    for (pnext = plugin; *pnext; pnext = &((*pnext)->next)) {
            /* list only one instance of type */
        q = strdup((*pnext)->typestr);
        if ((p = strchr(q, ':')))
            *p++ = '\0';
        if (!typestr_last || strcasecmp(typestr_last, q) != 0) {
            list = RALLOC(cnt+1,list,char*);
            list[cnt++] = q;
        }
        typestr_last = q;
    }

    *sz = cnt;
    return list;
}

void gvplugin_write_status(GVC_t * gvc)
{
    int api;

#ifdef ENABLE_LTDL
    if (gvc->common.demand_loading) {
        fprintf(stderr,"The plugin configuration file:\n\t%s\n", gvc->config_path);
        if (gvc->config_found)
            fprintf(stderr,"\t\twas successfully loaded.\n");
        else
            fprintf(stderr,"\t\twas not found or not usable. No on-demand plugins.\n");
    }
    else {
        fprintf(stderr,"Demand loading of plugins is disabled.\n");
    }
#endif

    for (api = 0; api < ARRAY_SIZE(api_names); api++) {
        if (gvc->common.verbose >= 2) 
            fprintf(stderr,"    %s\t: %s\n", api_names[api], gvplugin_list(gvc, api, ":"));
        else
            fprintf(stderr,"    %s\t: %s\n", api_names[api], gvplugin_list(gvc, api, "?"));
    }

}

Agraph_t * gvplugin_graph(GVC_t * gvc)
{
    Agraph_t *g, *sg, *ssg;
    Agnode_t *n, *m;
    Agedge_t *e;
    Agsym_t *a;
    gvplugin_package_t *package;
    gvplugin_available_t **pnext;
    char bufa[100], *buf1, *buf2, bufb[100], *p, *q, *t;
    int api, found;

#ifndef WITH_CGRAPH
    aginit();
    agsetiodisc(NULL, gvfwrite, gvferror);
    /* set persistent attributes here */
    agraphattr(NULL, "label", "");
    agraphattr(NULL, "rankdir", "");
    agraphattr(NULL, "rank", "");
    agraphattr(NULL, "ranksep", "");
    agnodeattr(NULL, "label", NODENAME_ESC);

    g = agopen("G", AGDIGRAPH);
#else
    g = agopen("G", Agdirected, NIL(Agdisc_t *));
    agattr(g, AGRAPH, "label", "");
    agattr(g, AGRAPH, "rankdir", "");
    agattr(g, AGRAPH, "rank", "");
    agattr(g, AGRAPH, "ranksep", "");
    agattr(g, AGNODE, "label", NODENAME_ESC);
#endif

    a = agfindgraphattr(g, "rankdir");
#ifndef WITH_CGRAPH
    agxset(g, a->index, "LR");
#else
    agxset(g, a, "LR");
#endif

    a = agfindgraphattr(g, "ranksep");
#ifndef WITH_CGRAPH
    agxset(g, a->index, "1.5");
#else
    agxset(g, a, "1.5");
#endif

    a = agfindgraphattr(g, "label");
#ifndef WITH_CGRAPH
    agxset(g, a->index, "Plugins");
#else
    agxset(g, a, "Plugins");
#endif

    for (package = gvc->packages; package; package = package->next) {
        strcpy(bufa, "cluster_");
        strcat(bufa, package->name); 
#ifndef WITH_CGRAPH
        sg = agsubg(g, bufa);
#else
        sg = agsubg(g, bufa, 1);
#endif
        a = agfindgraphattr(sg, "label");
#ifndef WITH_CGRAPH
        agxset(sg, a->index, package->name);
#else
        agxset(sg, a, package->name);
#endif
        strcpy(bufa, package->name); 
        strcat(bufa, "_");
        buf1 = bufa + strlen(bufa);
        for (api = 0; api < ARRAY_SIZE(api_names); api++) {
            found = 0;
            strcpy(buf1, api_names[api]);
#ifndef WITH_CGRAPH
            ssg = agsubg(sg, bufa);
#else
            ssg = agsubg(sg, bufa, 1);
#endif
            a = agfindgraphattr(ssg, "rank");
#ifndef WITH_CGRAPH
            agxset(ssg, a->index, "same");
#else
            agxset(ssg, a, "same");
#endif
            strcat(buf1, "_");
            buf2 = bufa + strlen(bufa);
            for (pnext = &(gvc->apis[api]); *pnext; pnext = &((*pnext)->next)) {
                if ((*pnext)->package == package) {
                    found++;
                    t = q = strdup((*pnext)->typestr);
                    if ((p = strchr(q, ':'))) *p++ = '\0';
                    /* Now p = renderer, e.g. "gd"
                     * and q = device, e.g. "png"
                     * or  q = imageloader, e.g. "png" */
                    switch (api) {
                    case API_device:
                    case API_loadimage:

                        /* hack for aliases */
                        if (!strncmp(q,"jp",2))
                            q = "jpeg/jpe/jpg";
                        else if (!strncmp(q,"tif",3))
                            q = "tiff/tif";
                        else if (!strcmp(q,"x11") || !strcmp(q,"xlib"))
                            q = "x11/xlib";
                        else if (!strcmp(q,"dot") || !strcmp(q,"gv"))
                            q = "gv/dot";

                        strcpy(buf2, q);
#ifndef WITH_CGRAPH
                        n = agnode(ssg, bufa);
#else
                        n = agnode(ssg, bufa, 1);
#endif
                        a = agfindnodeattr(g, "label");
#ifndef WITH_CGRAPH
                        agxset(n, a->index, q);
#else
                        agxset(n, a, q);
#endif
                        if (! (p && *p)) {
                            strcpy(bufb, "render_cg");
                            m = agfindnode(sg, bufb);
                            if (!m) {
#ifndef WITH_CGRAPH
                                m = agnode(sg, bufb);
#else
                                m = agnode(sg, bufb, 1);
#endif
                                a = agfindgraphattr(g, "label");
#ifndef WITH_CGRAPH
                                agxset(m, a->index, "cg");
#else
                                agxset(m, a, "cg");
#endif
                            }
#ifndef WITH_CGRAPH
                            agedge(sg, m, n);
#else
                            agedge(sg, m, n, NULL, 1);
#endif
                        }
                        break;
                    case API_render:
                        strcpy(bufb, api_names[api]);
                        strcat(bufb, "_");
                        strcat(bufb, q);
#ifndef WITH_CGRAPH
                        n = agnode(ssg, bufb);
#else
                        n = agnode(ssg, bufb, 1);
#endif
                        a = agfindnodeattr(g, "label");
#ifndef WITH_CGRAPH
                        agxset(n, a->index, q);
#else
                        agxset(n, a, q);
#endif
                        break;
                    default:
                        break;
                    }
                    free(t);
                }
            }
            if (!found)
#ifndef WITH_CGRAPH
                agdelete(ssg->meta_node->graph, ssg->meta_node);
#else
                agdelete(g, ssg);
#endif
        }
    }

#ifndef WITH_CGRAPH
    ssg = agsubg(g, "output_formats");
#else
    ssg = agsubg(g, "output_formats", 1);
#endif
    a = agfindgraphattr(ssg, "rank");
#ifndef WITH_CGRAPH
    agxset(ssg, a->index, "same");
#else
    agxset(ssg, a, "same");
#endif
    for (package = gvc->packages; package; package = package->next) {
        strcpy(bufa, package->name); 
        strcat(bufa, "_");
        buf1 = bufa + strlen(bufa);
        for (api = 0; api < ARRAY_SIZE(api_names); api++) {
            strcpy(buf1, api_names[api]);
            strcat(buf1, "_");
            buf2 = bufa + strlen(bufa);
            for (pnext = &(gvc->apis[api]); *pnext; pnext = &((*pnext)->next)) {
                if ((*pnext)->package == package) {
                    t = q = strdup((*pnext)->typestr);
                    if ((p = strchr(q, ':'))) *p++ = '\0';
                    /* Now p = renderer, e.g. "gd"
                     * and q = device, e.g. "png"
                     * or  q = imageloader, e.g. "png" */

                    /* hack for aliases */
                    if (!strncmp(q,"jp",2))
                        q = "jpeg/jpe/jpg";
                    else if (!strncmp(q,"tif",3))
                        q = "tiff/tif";
                    else if (!strcmp(q,"x11") || !strcmp(q,"xlib"))
                        q = "x11/xlib";
                    else if (!strcmp(q,"dot") || !strcmp(q,"gv"))
                        q = "gv/dot";

                    switch (api) {
                    case API_device:
                        strcpy(buf2, q);
#ifndef WITH_CGRAPH
                        n = agnode(g, bufa);
#else
                        n = agnode(g, bufa, 1);
#endif
                        strcpy(bufb, "output_");
                        strcat(bufb, q);
                        m = agfindnode(ssg, bufb);
                        if (!m) {
#ifndef WITH_CGRAPH
                            m = agnode(ssg, bufb);
#else
                            m = agnode(ssg, bufb, 1);
#endif
                            a = agfindnodeattr(g, "label");
#ifndef WITH_CGRAPH
                            agxset(m, a->index, q);
#else
                            agxset(m, a, q);
#endif
                        }
                        e = agfindedge(g, n, m);
                        if (!e)
#ifndef WITH_CGRAPH
                            e = agedge(g, n, m);
#else
                            e = agedge(g, n, m, NULL, 1);
#endif
                        if (p && *p) {
                            strcpy(bufb, "render_");
                            strcat(bufb, p);
                            m = agfindnode(ssg, bufb);
                            if (!m)
#ifndef WITH_CGRAPH
                                m = agnode(g, bufb);
#else
                                m = agnode(g, bufb, 1);
#endif
                            e = agfindedge(g, m, n);
                            if (!e)
#ifndef WITH_CGRAPH
                                e = agedge(g, m, n);
#else
                                e = agedge(g, m, n, NULL, 1);
#endif
                        }
                        break;
                    case API_loadimage:
                        strcpy(buf2, q);
#ifndef WITH_CGRAPH
                        n = agnode(g, bufa);
#else
                        n = agnode(g, bufa, 1);
#endif
                        strcpy(bufb, "input_");
                        strcat(bufb, q);
                        m = agfindnode(g, bufb);
                        if (!m) {
#ifndef WITH_CGRAPH
                            m = agnode(g, bufb);
#else
                            m = agnode(g, bufb, 1);
#endif
                            a = agfindnodeattr(g, "label");
#ifndef WITH_CGRAPH
                            agxset(m, a->index, q);
#else
                            agxset(m, a, q);
#endif
                        }
                        e = agfindedge(g, m, n);
                        if (!e)
#ifndef WITH_CGRAPH
                            e = agedge(g, m, n);
#else
                            e = agedge(g, m, n, NULL, 1);
#endif
                        strcpy(bufb, "render_");
                        strcat(bufb, p);
                        m = agfindnode(g, bufb);
                        if (!m)
#ifndef WITH_CGRAPH
                            m = agnode(g, bufb); 
#else
                            m = agnode(g, bufb, 1); 
#endif
                        e = agfindedge(g, n, m);
                        if (!e)
#ifndef WITH_CGRAPH
                            e = agedge(g, n, m);
#else
                            e = agedge(g, n, m, NULL, 1);
#endif
                        break;
                    default:
                        break;
                    }
                    free(t);
                }
            }
        }
    }

    return g;
}