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path: root/src/plugin_tc.c
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#include "common.h"

#define RRD_TYPE_TC                 "tc"
#define RRD_TYPE_TC_LEN             strlen(RRD_TYPE_TC)

// ----------------------------------------------------------------------------
// /sbin/tc processor
// this requires the script plugins.d/tc-qos-helper.sh

#define TC_LINE_MAX 1024

struct tc_class {
    avl avl;

    char *id;
    uint32_t hash;

    char *name;

    char *leafid;
    uint32_t leaf_hash;

    char *parentid;
    uint32_t parent_hash;

    char hasparent;
    char isleaf;
    unsigned long long bytes;
    unsigned long long packets;
    unsigned long long dropped;
    unsigned long long overlimits;
    unsigned long long requeues;
    unsigned long long lended;
    unsigned long long borrowed;
    unsigned long long giants;
    unsigned long long tokens;
    unsigned long long ctokens;

    RRDDIM *rd_bytes;
    RRDDIM *rd_packets;
    RRDDIM *rd_dropped;

    char name_updated;
    char updated;   // updated bytes
    int seen;       // seen in the tc list (even without bytes)

    struct tc_class *next;
    struct tc_class *prev;
};

struct tc_device {
    avl avl;

    char *id;
    uint32_t hash;

    char *name;
    char *family;

    char name_updated;
    char family_updated;

    char enabled;
    char enabled_bytes;
    char enabled_packets;
    char enabled_dropped;

    RRDSET *st_bytes;
    RRDSET *st_packets;
    RRDSET *st_dropped;

    avl_tree classes_index;

    struct tc_class *classes;

    struct tc_device *next;
    struct tc_device *prev;
};


struct tc_device *tc_device_root = NULL;

// ----------------------------------------------------------------------------
// tc_device index

static int tc_device_compare(void* a, void* b) {
    if(((struct tc_device *)a)->hash < ((struct tc_device *)b)->hash) return -1;
    else if(((struct tc_device *)a)->hash > ((struct tc_device *)b)->hash) return 1;
    else return strcmp(((struct tc_device *)a)->id, ((struct tc_device *)b)->id);
}

avl_tree tc_device_root_index = {
        NULL,
        tc_device_compare
};

#define tc_device_index_add(st) avl_insert(&tc_device_root_index, (avl *)(st))
#define tc_device_index_del(st) avl_remove(&tc_device_root_index, (avl *)(st))

static inline struct tc_device *tc_device_index_find(const char *id, uint32_t hash) {
    struct tc_device tmp;
    tmp.id = (char *)id;
    tmp.hash = (hash)?hash:simple_hash(tmp.id);

    return (struct tc_device *)avl_search(&(tc_device_root_index), (avl *)&tmp);
}


// ----------------------------------------------------------------------------
// tc_class index

static int tc_class_compare(void* a, void* b) {
    if(((struct tc_class *)a)->hash < ((struct tc_class *)b)->hash) return -1;
    else if(((struct tc_class *)a)->hash > ((struct tc_class *)b)->hash) return 1;
    else return strcmp(((struct tc_class *)a)->id, ((struct tc_class *)b)->id);
}

#define tc_class_index_add(st, rd) avl_insert(&((st)->classes_index), (avl *)(rd))
#define tc_class_index_del(st, rd) avl_remove(&((st)->classes_index), (avl *)(rd))

static inline struct tc_class *tc_class_index_find(struct tc_device *st, const char *id, uint32_t hash) {
    struct tc_class tmp;
    tmp.id = (char *)id;
    tmp.hash = (hash)?hash:simple_hash(tmp.id);

    return (struct tc_class *)avl_search(&(st->classes_index), (avl *) &tmp);
}

// ----------------------------------------------------------------------------

static inline void tc_class_free(struct tc_device *n, struct tc_class *c) {
    if(c == n->classes) {
        if(c->next)
            n->classes = c->next;
        else
            n->classes = c->prev;
    }
    if(c->next) c->next->prev = c->prev;
    if(c->prev) c->prev->next = c->next;

    debug(D_TC_LOOP, "Removing from device '%s' class '%s', parentid '%s', leafid '%s', seen=%d", n->id, c->id, c->parentid?c->parentid:"", c->leafid?c->leafid:"", c->seen);

    tc_class_index_del(n, c);

    freez(c->id);
    freez(c->name);
    freez(c->leafid);
    freez(c->parentid);
    freez(c);
}

static inline void tc_device_classes_cleanup(struct tc_device *d) {
    static int cleanup_every = 999;

    if(unlikely(cleanup_every > 0)) {
        cleanup_every = (int) config_get_number("plugin:tc", "cleanup unused classes every", 60);
        if(cleanup_every < 0) cleanup_every = -cleanup_every;
    }

    d->name_updated = 0;
    d->family_updated = 0;

    struct tc_class *c = d->classes;
    while(c) {
        if(unlikely(cleanup_every > 0 && c->seen >= cleanup_every)) {
            struct tc_class *nc = c->next;
            tc_class_free(d, c);
            c = nc;
        }
        else {
            c->updated = 0;
            c->name_updated = 0;

            c = c->next;
        }
    }
}

static inline void tc_device_commit(struct tc_device *d) {
    static int enable_new_interfaces = -1, enable_bytes = -1, enable_packets = -1, enable_dropped = -1;

    if(unlikely(enable_new_interfaces == -1)) {
        enable_new_interfaces = config_get_boolean_ondemand("plugin:tc", "enable new interfaces detected at runtime", CONFIG_ONDEMAND_YES);
        enable_bytes          = config_get_boolean_ondemand("plugin:tc", "enable traffic charts for all interfaces", CONFIG_ONDEMAND_ONDEMAND);
        enable_packets        = config_get_boolean_ondemand("plugin:tc", "enable packets charts for all interfaces", CONFIG_ONDEMAND_ONDEMAND);
        enable_dropped        = config_get_boolean_ondemand("plugin:tc", "enable dropped charts for all interfaces", CONFIG_ONDEMAND_ONDEMAND);
    }

    // we only need to add leaf classes
    struct tc_class *c, *x;
    unsigned long long bytes_sum = 0, packets_sum = 0, dropped_sum = 0;
    int active_classes = 0;

    // set all classes
    for(c = d->classes ; c ; c = c->next) {
        c->isleaf = 1;
        c->hasparent = 0;
    }

    // mark the classes as leafs and parents
    for(c = d->classes ; c ; c = c->next) {
        if(unlikely(!c->updated)) continue;

        for(x = d->classes ; x ; x = x->next) {
            if(unlikely(!x->updated)) continue;

            if(unlikely(c == x)) continue;

            if(x->parentid && (
                (               c->hash      == x->parent_hash && strcmp(c->id,     x->parentid) == 0) ||
                (c->leafid   && c->leaf_hash == x->parent_hash && strcmp(c->leafid, x->parentid) == 0))) {
                // debug(D_TC_LOOP, "TC: In device '%s', class '%s' (leafid: '%s') has as leaf class '%s' (parentid: '%s').", d->name?d->name:d->id, c->name?c->name:c->id, c->leafid?c->leafid:c->id, x->name?x->name:x->id, x->parentid?x->parentid:x->id);
                c->isleaf = 0;
                x->hasparent = 1;
            }
        }
    }

    // debugging:
    /*
    for ( c = d->classes ; c ; c = c->next) {
        if(c->isleaf && c->hasparent) debug(D_TC_LOOP, "TC: Device %s, class %s, OK", d->name, c->id);
        else debug(D_TC_LOOP, "TC: Device %s, class %s, IGNORE (isleaf: %d, hasparent: %d, parent: %s)", d->name, c->id, c->isleaf, c->hasparent, c->parentid);
    }
    */

    // we need at least a class
    for(c = d->classes ; c ; c = c->next) {
        // debug(D_TC_LOOP, "TC: Device '%s', class '%s', isLeaf=%d, HasParent=%d, Seen=%d", d->name?d->name:d->id, c->name?c->name:c->id, c->isleaf, c->hasparent, c->seen);
        if(!c->updated) continue;
        if(c->isleaf && c->hasparent) {
            active_classes++;
            bytes_sum += c->bytes;
            packets_sum += c->packets;
            dropped_sum += c->dropped;
        }
    }

    if(unlikely(!active_classes)) {
        debug(D_TC_LOOP, "TC: Ignoring TC device '%s'. No leaf classes.", d->name?d->name:d->id);
        tc_device_classes_cleanup(d);
        return;
    }

    if(unlikely(d->enabled == -1)) {
        char var_name[CONFIG_MAX_NAME + 1];
        snprintfz(var_name, CONFIG_MAX_NAME, "qos for %s", d->id);
        d->enabled         = config_get_boolean_ondemand("plugin:tc", var_name, enable_new_interfaces);

        snprintfz(var_name, CONFIG_MAX_NAME, "traffic chart for %s", d->id);
        d->enabled_bytes   = config_get_boolean_ondemand("plugin:tc", var_name, enable_bytes);

        snprintfz(var_name, CONFIG_MAX_NAME, "packets chart for %s", d->id);
        d->enabled_packets = config_get_boolean_ondemand("plugin:tc", var_name, enable_packets);

        snprintfz(var_name, CONFIG_MAX_NAME, "dropped packets chart for %s", d->id);
        d->enabled_dropped = config_get_boolean_ondemand("plugin:tc", var_name, enable_dropped);
    }

    if(likely(d->enabled)) {
        // --------------------------------------------------------------------
        // bytes

        if(d->enabled_bytes == CONFIG_ONDEMAND_YES || (d->enabled_bytes == CONFIG_ONDEMAND_ONDEMAND && bytes_sum)) {
            d->enabled_bytes = CONFIG_ONDEMAND_YES;

            if(unlikely(!d->st_bytes)) {
                d->st_bytes = rrdset_find_bytype(RRD_TYPE_TC, d->id);
                if(unlikely(!d->st_bytes)) {
                    debug(D_TC_LOOP, "TC: Creating new chart for device '%s'", d->name?d->name:d->id);
                    d->st_bytes = rrdset_create(RRD_TYPE_TC, d->id, d->name?d->name:d->id, d->family?d->family:d->id, RRD_TYPE_TC ".qos", "Class Usage", "kilobits/s", 7000, rrd_update_every, RRDSET_TYPE_STACKED);
                }
            }
            else {
                debug(D_TC_LOOP, "TC: Updating chart for device '%s'", d->name?d->name:d->id);
                rrdset_next_plugins(d->st_bytes);

                if(unlikely(d->name_updated && d->name && strcmp(d->id, d->name) != 0)) {
                    rrdset_set_name(d->st_bytes, d->name);
                    d->name_updated = 0;
                }

                // FIXME
                // update the family
            }

            for(c = d->classes ; c ; c = c->next) {
                if(unlikely(!c->updated)) continue;

                if(c->isleaf && c->hasparent) {
                    c->seen++;

                    if(unlikely(!c->rd_bytes)) {
                        c->rd_bytes = rrddim_find(d->st_bytes, c->id);
                        if(unlikely(!c->rd_bytes)) {
                            debug(D_TC_LOOP, "TC: Adding to chart '%s', dimension '%s' (name: '%s')", d->st_bytes->id, c->id, c->name);

                            // new class, we have to add it
                            c->rd_bytes = rrddim_add(d->st_bytes, c->id, c->name?c->name:c->id, 8, 1024, RRDDIM_INCREMENTAL);
                        }
                        else debug(D_TC_LOOP, "TC: Updating chart '%s', dimension '%s'", d->st_bytes->id, c->id);
                    }

                    rrddim_set_by_pointer(d->st_bytes, c->rd_bytes, c->bytes);

                    // if it has a name, different to the id
                    if(unlikely(c->name_updated && c->name && strcmp(c->id, c->name) != 0)) {
                        // update the rrd dimension with the new name
                        debug(D_TC_LOOP, "TC: Setting chart '%s', dimension '%s' name to '%s'", d->st_bytes->id, c->rd_bytes->id, c->name);
                        rrddim_set_name(d->st_bytes, c->rd_bytes, c->name);
                    }
                }
            }
            rrdset_done(d->st_bytes);
        }

        // --------------------------------------------------------------------
        // packets
        
        if(d->enabled_packets == CONFIG_ONDEMAND_YES || (d->enabled_packets == CONFIG_ONDEMAND_ONDEMAND && packets_sum)) {
            d->enabled_packets = CONFIG_ONDEMAND_YES;

            if(unlikely(!d->st_packets)) {
                char id[RRD_ID_LENGTH_MAX + 1];
                char name[RRD_ID_LENGTH_MAX + 1];
                snprintfz(id, RRD_ID_LENGTH_MAX, "%s_packets", d->id);
                snprintfz(name, RRD_ID_LENGTH_MAX, "%s_packets", d->name?d->name:d->id);

                d->st_packets = rrdset_find_bytype(RRD_TYPE_TC, id);
                if(unlikely(!d->st_packets)) {
                    debug(D_TC_LOOP, "TC: Creating new _packets chart for device '%s'", d->name?d->name:d->id);
                    d->st_packets = rrdset_create(RRD_TYPE_TC, id, name, d->family?d->family:d->id, RRD_TYPE_TC ".qos_packets", "Class Packets", "packets/s", 7010, rrd_update_every, RRDSET_TYPE_STACKED);
                }
            }
            else {
                debug(D_TC_LOOP, "TC: Updating _packets chart for device '%s'", d->name?d->name:d->id);
                rrdset_next_plugins(d->st_packets);

                // FIXME
                // update the family
            }

            for(c = d->classes ; c ; c = c->next) {
                if(unlikely(!c->updated)) continue;

                if(c->isleaf && c->hasparent) {
                    if(unlikely(!c->rd_packets)) {
                        c->rd_packets = rrddim_find(d->st_packets, c->id);
                        if(unlikely(!c->rd_packets)) {
                            debug(D_TC_LOOP, "TC: Adding to chart '%s', dimension '%s' (name: '%s')", d->st_packets->id, c->id, c->name);

                            // new class, we have to add it
                            c->rd_packets = rrddim_add(d->st_packets, c->id, c->name?c->name:c->id, 1, 1, RRDDIM_INCREMENTAL);
                        }
                        else debug(D_TC_LOOP, "TC: Updating chart '%s', dimension '%s'", d->st_packets->id, c->id);
                    }

                    rrddim_set_by_pointer(d->st_packets, c->rd_packets, c->packets);

                    // if it has a name, different to the id
                    if(unlikely(c->name_updated && c->name && strcmp(c->id, c->name) != 0)) {
                        // update the rrd dimension with the new name
                        debug(D_TC_LOOP, "TC: Setting chart '%s', dimension '%s' name to '%s'", d->st_packets->id, c->rd_packets->id, c->name);
                        rrddim_set_name(d->st_packets, c->rd_packets, c->name);
                    }
                }
            }
            rrdset_done(d->st_packets);
        }

        // --------------------------------------------------------------------
        // dropped
        
        if(d->enabled_dropped == CONFIG_ONDEMAND_YES || (d->enabled_dropped == CONFIG_ONDEMAND_ONDEMAND && dropped_sum)) {
            d->enabled_dropped = CONFIG_ONDEMAND_YES;
            
            if(unlikely(!d->st_dropped)) {
                char id[RRD_ID_LENGTH_MAX + 1];
                char name[RRD_ID_LENGTH_MAX + 1];
                snprintfz(id, RRD_ID_LENGTH_MAX, "%s_dropped", d->id);
                snprintfz(name, RRD_ID_LENGTH_MAX, "%s_dropped", d->name?d->name:d->id);

                d->st_dropped = rrdset_find_bytype(RRD_TYPE_TC, id);
                if(unlikely(!d->st_dropped)) {
                    debug(D_TC_LOOP, "TC: Creating new _dropped chart for device '%s'", d->name?d->name:d->id);
                    d->st_dropped = rrdset_create(RRD_TYPE_TC, id, name, d->family?d->family:d->id, RRD_TYPE_TC ".qos_dropped", "Class Dropped Packets", "packets/s", 7020, rrd_update_every, RRDSET_TYPE_STACKED);
                }
            }
            else {
                debug(D_TC_LOOP, "TC: Updating _dropped chart for device '%s'", d->name?d->name:d->id);
                rrdset_next_plugins(d->st_dropped);

                // FIXME
                // update the family
            }

            for(c = d->classes ; c ; c = c->next) {
                if(unlikely(!c->updated)) continue;

                if(c->isleaf && c->hasparent) {
                    if(unlikely(!c->rd_dropped)) {
                        c->rd_dropped = rrddim_find(d->st_dropped, c->id);
                        if(unlikely(!c->rd_dropped)) {
                            debug(D_TC_LOOP, "TC: Adding to chart '%s', dimension '%s' (name: '%s')", d->st_dropped->id, c->id, c->name);

                            // new class, we have to add it
                            c->rd_dropped = rrddim_add(d->st_dropped, c->id, c->name?c->name:c->id, 1, 1, RRDDIM_INCREMENTAL);
                        }
                        else debug(D_TC_LOOP, "TC: Updating chart '%s', dimension '%s'", d->st_dropped->id, c->id);
                    }

                    rrddim_set_by_pointer(d->st_dropped, c->rd_dropped, c->dropped);

                    // if it has a name, different to the id
                    if(unlikely(c->name_updated && c->name && strcmp(c->id, c->name) != 0)) {
                        // update the rrd dimension with the new name
                        debug(D_TC_LOOP, "TC: Setting chart '%s', dimension '%s' name to '%s'", d->st_dropped->id, c->rd_dropped->id, c->name);
                        rrddim_set_name(d->st_dropped, c->rd_dropped, c->name);
                    }
                }
            }
            rrdset_done(d->st_dropped);
        }
    }

    tc_device_classes_cleanup(d);
}

static inline void tc_device_set_class_name(struct tc_device *d, char *id, char *name)
{
    struct tc_class *c = tc_class_index_find(d, id, 0);
    if(likely(c)) {
        freez(c->name);
        c->name = NULL;

        if(likely(name && *name && strcmp(c->id, name) != 0)) {
            debug(D_TC_LOOP, "TC: Setting device '%s', class '%s' name to '%s'", d->id, id, name);
            c->name = strdupz(name);
            c->name_updated = 1;
        }
    }
}

static inline void tc_device_set_device_name(struct tc_device *d, char *name) {
    freez(d->name);
    d->name = NULL;

    if(likely(name && *name && strcmp(d->id, name) != 0)) {
        debug(D_TC_LOOP, "TC: Setting device '%s' name to '%s'", d->id, name);
        d->name = strdupz(name);
        d->name_updated = 1;
    }
}

static inline void tc_device_set_device_family(struct tc_device *d, char *family) {
    freez(d->family);
    d->family = NULL;

    if(likely(family && *family && strcmp(d->id, family) != 0)) {
        debug(D_TC_LOOP, "TC: Setting device '%s' family to '%s'", d->id, family);
        d->family = strdupz(family);
        d->family_updated = 1;
    }
    // no need for null termination - it is already null
}

static inline struct tc_device *tc_device_create(char *id)
{
    struct tc_device *d = tc_device_index_find(id, 0);

    if(!d) {
        debug(D_TC_LOOP, "TC: Creating device '%s'", id);

        d = callocz(1, sizeof(struct tc_device));

        d->id = strdupz(id);
        d->hash = simple_hash(d->id);
        d->enabled = -1;

        avl_init(&d->classes_index, tc_class_compare);
        tc_device_index_add(d);

        if(!tc_device_root) {
            tc_device_root = d;
        }
        else {
            d->next = tc_device_root;
            tc_device_root->prev = d;
            tc_device_root = d;
        }
    }

    return(d);
}

static inline struct tc_class *tc_class_add(struct tc_device *n, char *id, char *parentid, char *leafid)
{
    struct tc_class *c = tc_class_index_find(n, id, 0);

    if(!c) {
        debug(D_TC_LOOP, "TC: Creating in device '%s', class id '%s', parentid '%s', leafid '%s'", n->id, id, parentid?parentid:"", leafid?leafid:"");

        c = callocz(1, sizeof(struct tc_class));

        if(n->classes) n->classes->prev = c;
        c->next = n->classes;
        n->classes = c;

        c->id = strdupz(id);
        c->hash = simple_hash(c->id);

        if(parentid && *parentid) {
            c->parentid = strdupz(parentid);
            c->parent_hash = simple_hash(c->parentid);
        }

        if(leafid && *leafid) {
            c->leafid = strdupz(leafid);
            c->leaf_hash = simple_hash(c->leafid);
        }

        tc_class_index_add(n, c);
    }

    c->seen = 1;

    return(c);
}

static inline void tc_device_free(struct tc_device *n)
{
    if(n->next) n->next->prev = n->prev;
    if(n->prev) n->prev->next = n->next;
    if(tc_device_root == n) {
        if(n->next) tc_device_root = n->next;
        else tc_device_root = n->prev;
    }

    tc_device_index_del(n);

    while(n->classes) tc_class_free(n, n->classes);

    freez(n->id);
    freez(n->name);
    freez(n->family);
    freez(n);
}

static inline void tc_device_free_all()
{
    while(tc_device_root)
        tc_device_free(tc_device_root);
}

#define MAX_WORDS 20

static inline int tc_space(char c) {
    switch(c) {
    case ' ':
    case '\t':
    case '\r':
    case '\n':
        return 1;

    default:
        return 0;
    }
}

static inline void tc_split_words(char *str, char **words, int max_words) {
    char *s = str;
    int i = 0;

    // skip all white space
    while(tc_space(*s)) s++;

    // store the first word
    words[i++] = s;

    // while we have something
    while(*s) {
        // if it is a space
        if(unlikely(tc_space(*s))) {

            // terminate the word
            *s++ = '\0';

            // skip all white space
            while(tc_space(*s)) s++;

            // if we reached the end, stop
            if(!*s) break;

            // store the next word
            if(i < max_words) words[i++] = s;
            else break;
        }
        else s++;
    }

    // terminate the words
    while(i < max_words) words[i++] = NULL;
}

pid_t tc_child_pid = 0;
void *tc_main(void *ptr) {
    (void)ptr;

    info("TC thread created with task id %d", gettid());

    if(pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, NULL) != 0)
        error("Cannot set pthread cancel type to DEFERRED.");

    if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
        error("Cannot set pthread cancel state to ENABLE.");

    struct rusage thread;
    RRDSET *stcpu = NULL, *sttime = NULL;

    char buffer[TC_LINE_MAX+1] = "";
    char *words[MAX_WORDS] = { NULL };

    uint32_t BEGIN_HASH = simple_hash("BEGIN");
    uint32_t END_HASH = simple_hash("END");
    uint32_t CLASS_HASH = simple_hash("class");
    uint32_t SENT_HASH = simple_hash("Sent");
    uint32_t LENDED_HASH = simple_hash("lended:");
    uint32_t TOKENS_HASH = simple_hash("tokens:");
    uint32_t SETDEVICENAME_HASH = simple_hash("SETDEVICENAME");
    uint32_t SETDEVICEGROUP_HASH = simple_hash("SETDEVICEGROUP");
    uint32_t SETCLASSNAME_HASH = simple_hash("SETCLASSNAME");
    uint32_t WORKTIME_HASH = simple_hash("WORKTIME");
#ifdef DETACH_PLUGINS_FROM_NETDATA
    uint32_t MYPID_HASH = simple_hash("MYPID");
#endif
    uint32_t first_hash;

    snprintfz(buffer, TC_LINE_MAX, "%s/tc-qos-helper.sh", config_get("plugins", "plugins directory", PLUGINS_DIR));
    char *tc_script = config_get("plugin:tc", "script to run to get tc values", buffer);
    
    for(;1;) {
        if(unlikely(netdata_exit)) break;

        FILE *fp;
        struct tc_device *device = NULL;
        struct tc_class *class = NULL;

        snprintfz(buffer, TC_LINE_MAX, "exec %s %d", tc_script, rrd_update_every);
        debug(D_TC_LOOP, "executing '%s'", buffer);

        fp = mypopen(buffer, &tc_child_pid);
        if(unlikely(!fp)) {
            error("TC: Cannot popen(\"%s\", \"r\").", buffer);
            pthread_exit(NULL);
            return NULL;
        }

        while(fgets(buffer, TC_LINE_MAX, fp) != NULL) {
            if(unlikely(netdata_exit)) break;

            buffer[TC_LINE_MAX] = '\0';
            // debug(D_TC_LOOP, "TC: read '%s'", buffer);

            tc_split_words(buffer, words, MAX_WORDS);

            if(unlikely(!words[0] || !*words[0])) {
                // debug(D_TC_LOOP, "empty line");
                continue;
            }
            // else debug(D_TC_LOOP, "First word is '%s'", words[0]);

            first_hash = simple_hash(words[0]);

            if(unlikely(device && first_hash == CLASS_HASH && strcmp(words[0], "class") == 0)) {
                // debug(D_TC_LOOP, "CLASS line on class id='%s', parent='%s', parentid='%s', leaf='%s', leafid='%s'", words[2], words[3], words[4], words[5], words[6]);

                // words[1] : class type
                // words[2] : N:XX
                // words[3] : parent or root
                if(likely(words[1] && words[2] && words[3] && (strcmp(words[3], "parent") == 0 || strcmp(words[3], "root") == 0))) {
                    //char *type     = words[1];  // the class: htb, fq_codel, etc

                    // we are only interested for HTB classes
                    //if(strcmp(type, "htb") != 0) continue;

                    char *id       = words[2];  // the class major:minor
                    char *parent   = words[3];  // 'parent' or 'root'
                    char *parentid = words[4];  // the parent's id
                    char *leaf     = words[5];  // 'leaf'
                    char *leafid   = words[6];  // leafid

                    if(strcmp(parent, "root") == 0) {
                        parentid = NULL;
                        leafid = NULL;
                    }
                    else if(!leaf || strcmp(leaf, "leaf") != 0)
                        leafid = NULL;

                    char leafbuf[20 + 1] = "";
                    if(leafid && leafid[strlen(leafid) - 1] == ':') {
                        strncpyz(leafbuf, leafid, 20 - 1);
                        strcat(leafbuf, "1");
                        leafid = leafbuf;
                    }

                    class = tc_class_add(device, id, parentid, leafid);
                }
                else {
                    // clear the last class
                    class = NULL;
                }
            }
            else if(unlikely(first_hash == END_HASH && strcmp(words[0], "END") == 0)) {
                // debug(D_TC_LOOP, "END line");

                if(likely(device)) {
                    if(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL) != 0)
                        error("Cannot set pthread cancel state to DISABLE.");

                    tc_device_commit(device);
                    // tc_device_free(device);

                    if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
                        error("Cannot set pthread cancel state to ENABLE.");
                }

                device = NULL;
                class = NULL;
            }
            else if(unlikely(first_hash == BEGIN_HASH && strcmp(words[0], "BEGIN") == 0)) {
                // debug(D_TC_LOOP, "BEGIN line on device '%s'", words[1]);

                if(likely(words[1] && *words[1])) {
                    device = tc_device_create(words[1]);
                }
                else {
                    // tc_device_free(device);
                    device = NULL;
                }

                class = NULL;
            }
            else if(unlikely(device && class && first_hash == SENT_HASH && strcmp(words[0], "Sent") == 0)) {
                // debug(D_TC_LOOP, "SENT line '%s'", words[1]);
                if(likely(words[1] && *words[1])) {
                    class->bytes = strtoull(words[1], NULL, 10);
                    class->updated = 1;
                }
                else {
                    class->updated = 0;
                }

                if(likely(words[3] && *words[3]))
                    class->packets = strtoull(words[3], NULL, 10);

                if(likely(words[6] && *words[6]))
                    class->dropped = strtoull(words[6], NULL, 10);

                if(likely(words[8] && *words[8]))
                    class->overlimits = strtoull(words[8], NULL, 10);

                if(likely(words[10] && *words[10]))
                    class->requeues = strtoull(words[8], NULL, 10);
            }
            else if(unlikely(device && class && class->updated && first_hash == LENDED_HASH && strcmp(words[0], "lended:") == 0)) {
                // debug(D_TC_LOOP, "LENDED line '%s'", words[1]);
                if(likely(words[1] && *words[1]))
                    class->lended = strtoull(words[1], NULL, 10);

                if(likely(words[3] && *words[3]))
                    class->borrowed = strtoull(words[3], NULL, 10);

                if(likely(words[5] && *words[5]))
                    class->giants = strtoull(words[5], NULL, 10);
            }
            else if(unlikely(device && class && class->updated && first_hash == TOKENS_HASH && strcmp(words[0], "tokens:") == 0)) {
                // debug(D_TC_LOOP, "TOKENS line '%s'", words[1]);
                if(likely(words[1] && *words[1]))
                    class->tokens = strtoull(words[1], NULL, 10);

                if(likely(words[3] && *words[3]))
                    class->ctokens = strtoull(words[3], NULL, 10);
            }
            else if(unlikely(device && first_hash == SETDEVICENAME_HASH && strcmp(words[0], "SETDEVICENAME") == 0)) {
                // debug(D_TC_LOOP, "SETDEVICENAME line '%s'", words[1]);
                if(likely(words[1] && *words[1]))
                    tc_device_set_device_name(device, words[1]);
            }
            else if(unlikely(device && first_hash == SETDEVICEGROUP_HASH && strcmp(words[0], "SETDEVICEGROUP") == 0)) {
                // debug(D_TC_LOOP, "SETDEVICEGROUP line '%s'", words[1]);
                if(likely(words[1] && *words[1]))
                    tc_device_set_device_family(device, words[1]);
            }
            else if(unlikely(device && first_hash == SETCLASSNAME_HASH && strcmp(words[0], "SETCLASSNAME") == 0)) {
                // debug(D_TC_LOOP, "SETCLASSNAME line '%s' '%s'", words[1], words[2]);
                char *id    = words[1];
                char *path  = words[2];
                if(likely(id && *id && path && *path))
                    tc_device_set_class_name(device, id, path);
            }
            else if(unlikely(first_hash == WORKTIME_HASH && strcmp(words[0], "WORKTIME") == 0)) {
                // debug(D_TC_LOOP, "WORKTIME line '%s' '%s'", words[1], words[2]);
                getrusage(RUSAGE_THREAD, &thread);

                if(unlikely(!stcpu)) stcpu = rrdset_find("netdata.plugin_tc_cpu");
                if(unlikely(!stcpu)) {
                    stcpu = rrdset_create("netdata", "plugin_tc_cpu", NULL, "tc.helper", NULL, "NetData TC CPU usage", "milliseconds/s", 135000, rrd_update_every, RRDSET_TYPE_STACKED);
                    rrddim_add(stcpu, "user",  NULL,  1, 1000, RRDDIM_INCREMENTAL);
                    rrddim_add(stcpu, "system", NULL, 1, 1000, RRDDIM_INCREMENTAL);
                }
                else rrdset_next(stcpu);

                rrddim_set(stcpu, "user"  , thread.ru_utime.tv_sec * 1000000ULL + thread.ru_utime.tv_usec);
                rrddim_set(stcpu, "system", thread.ru_stime.tv_sec * 1000000ULL + thread.ru_stime.tv_usec);
                rrdset_done(stcpu);

                if(unlikely(!sttime)) stcpu = rrdset_find("netdata.plugin_tc_time");
                if(unlikely(!sttime)) {
                    sttime = rrdset_create("netdata", "plugin_tc_time", NULL, "tc.helper", NULL, "NetData TC script execution", "milliseconds/run", 135001, rrd_update_every, RRDSET_TYPE_AREA);
                    rrddim_add(sttime, "run_time",  "run time",  1, 1, RRDDIM_ABSOLUTE);
                }
                else rrdset_next(sttime);

                rrddim_set(sttime, "run_time", atoll(words[1]));
                rrdset_done(sttime);

            }
#ifdef DETACH_PLUGINS_FROM_NETDATA
            else if(unlikely(first_hash == MYPID_HASH && (strcmp(words[0], "MYPID") == 0))) {
                // debug(D_TC_LOOP, "MYPID line '%s'", words[1]);
                char *id = words[1];
                pid_t pid = atol(id);

                if(likely(pid)) tc_child_pid = pid;

                debug(D_TC_LOOP, "TC: Child PID is %d.", tc_child_pid);
            }
#endif
            //else {
            //  debug(D_TC_LOOP, "IGNORED line");
            //}
        }

        // fgets() failed or loop broke
        int code = mypclose(fp, tc_child_pid);
        tc_child_pid = 0;

        if(unlikely(device)) {
            // tc_device_free(device);
            device = NULL;
            class = NULL;
        }

        if(unlikely(netdata_exit)) {
            tc_device_free_all();
            pthread_exit(NULL);
            return NULL;
        }

        if(code == 1 || code == 127) {
            // 1 = DISABLE
            // 127 = cannot even run it
            error("TC: tc-qos-helper.sh exited with code %d. Disabling it.", code);

            tc_device_free_all();
            pthread_exit(NULL);
            return NULL;
        }

        sleep((unsigned int) rrd_update_every);
    }

    pthread_exit(NULL);
    return NULL;
}