15 files changed, 1244 insertions, 1116 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ae492c05d5..02e545d367 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -124,7 +124,7 @@ set(NETDATA_SOURCE_FILES
         src/web_client.h
         src/web_server.c
         src/web_server.h
-        src/rrdhost.c src/rrdfamily.c src/rrdset.c src/rrddim.c src/health_log.c src/health_config.c src/health_json.c)
+        src/rrdhost.c src/rrdfamily.c src/rrdset.c src/rrddim.c src/health_log.c src/health_config.c src/health_json.c src/rrdcalc.c src/rrdcalctemplate.c src/rrdvar.c src/rrddimvar.c src/rrdsetvar.c)
 
 set(APPS_PLUGIN_SOURCE_FILES
         src/appconfig.c
diff --git a/src/Makefile.am b/src/Makefile.am
index b5694fcaf4..9b006f4105 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -69,6 +69,11 @@ netdata_SOURCES = \
 	rrdfamily.c \
 	rrdhost.c \
 	rrdset.c \
+	rrdcalc.c \
+	rrdcalctemplate.c \
+	rrdvar.c \
+	rrddimvar.c \
+	rrdsetvar.c \
 	rrd2json.c rrd2json.h \
 	storage_number.c storage_number.h \
 	unit_test.c unit_test.h \
diff --git a/src/health.c b/src/health.c
index bd62fbcf8b..e3ded31954 100644
--- a/src/health.c
+++ b/src/health.c
@@ -1,1069 +1,9 @@
 #define NETDATA_HEALTH_INTERNALS
 #include "common.h"
 
-#define RRDVAR_MAX_LENGTH 1024
-
 int default_localhost_health_enabled = 1;
 
 // ----------------------------------------------------------------------------
-// RRDVAR management
-
-inline int rrdvar_fix_name(char *variable) {
-    int fixed = 0;
-    while(*variable) {
-        if (!isalnum(*variable) && *variable != '.' && *variable != '_') {
-            *variable++ = '_';
-            fixed++;
-        }
-        else
-            variable++;
-    }
-
-    return fixed;
-}
-
-int rrdvar_compare(void* a, void* b) {
-    if(((RRDVAR *)a)->hash < ((RRDVAR *)b)->hash) return -1;
-    else if(((RRDVAR *)a)->hash > ((RRDVAR *)b)->hash) return 1;
-    else return strcmp(((RRDVAR *)a)->name, ((RRDVAR *)b)->name);
-}
-
-static inline RRDVAR *rrdvar_index_add(avl_tree_lock *tree, RRDVAR *rv) {
-    RRDVAR *ret = (RRDVAR *)avl_insert_lock(tree, (avl *)(rv));
-    if(ret != rv)
-        debug(D_VARIABLES, "Request to insert RRDVAR '%s' into index failed. Already exists.", rv->name);
-
-    return ret;
-}
-
-static inline RRDVAR *rrdvar_index_del(avl_tree_lock *tree, RRDVAR *rv) {
-    RRDVAR *ret = (RRDVAR *)avl_remove_lock(tree, (avl *)(rv));
-    if(!ret)
-        error("Request to remove RRDVAR '%s' from index failed. Not Found.", rv->name);
-
-    return ret;
-}
-
-static inline RRDVAR *rrdvar_index_find(avl_tree_lock *tree, const char *name, uint32_t hash) {
-    RRDVAR tmp;
-    tmp.name = (char *)name;
-    tmp.hash = (hash)?hash:simple_hash(tmp.name);
-
-    return (RRDVAR *)avl_search_lock(tree, (avl *)&tmp);
-}
-
-static inline void rrdvar_free(RRDHOST *host, avl_tree_lock *tree, RRDVAR *rv) {
-    (void)host;
-
-    if(!rv) return;
-
-    if(tree) {
-        debug(D_VARIABLES, "Deleting variable '%s'", rv->name);
-        if(unlikely(!rrdvar_index_del(tree, rv)))
-            error("Attempted to delete variable '%s' from host '%s', but it is not found.", rv->name, host->hostname);
-    }
-
-    freez(rv->name);
-    freez(rv);
-}
-
-static inline RRDVAR *rrdvar_create_and_index(const char *scope, avl_tree_lock *tree, const char *name, int type, void *value) {
-    char *variable = strdupz(name);
-    rrdvar_fix_name(variable);
-    uint32_t hash = simple_hash(variable);
-
-    RRDVAR *rv = rrdvar_index_find(tree, variable, hash);
-    if(unlikely(!rv)) {
-        debug(D_VARIABLES, "Variable '%s' not found in scope '%s'. Creating a new one.", variable, scope);
-
-        rv = callocz(1, sizeof(RRDVAR));
-        rv->name = variable;
-        rv->hash = hash;
-        rv->type = type;
-        rv->value = value;
-
-        RRDVAR *ret = rrdvar_index_add(tree, rv);
-        if(unlikely(ret != rv)) {
-            debug(D_VARIABLES, "Variable '%s' in scope '%s' already exists", variable, scope);
-            rrdvar_free(NULL, NULL, rv);
-            rv = NULL;
-        }
-        else
-            debug(D_VARIABLES, "Variable '%s' created in scope '%s'", variable, scope);
-    }
-    else {
-        debug(D_VARIABLES, "Variable '%s' is already found in scope '%s'.", variable, scope);
-
-        // already exists
-        freez(variable);
-
-        // this is important
-        // it must return NULL - not the existing variable - or double-free will happen
-        rv = NULL;
-    }
-
-    return rv;
-}
-
-// ----------------------------------------------------------------------------
-// CUSTOM VARIABLES
-
-RRDVAR *rrdvar_custom_host_variable_create(RRDHOST *host, const char *name) {
-    calculated_number *v = callocz(1, sizeof(calculated_number));
-    *v = NAN;
-    RRDVAR *rv = rrdvar_create_and_index("host", &host->variables_root_index, name, RRDVAR_TYPE_CALCULATED_ALLOCATED, v);
-    if(unlikely(!rv)) {
-        free(v);
-        error("Requested variable '%s' already exists - possibly 2 plugins will be updating it at the same time", name);
-
-        char *variable = strdupz(name);
-        rrdvar_fix_name(variable);
-        uint32_t hash = simple_hash(variable);
-
-        rv = rrdvar_index_find(&host->variables_root_index, variable, hash);
-    }
-
-    return rv;
-}
-
-void rrdvar_custom_host_variable_destroy(RRDHOST *host, const char *name) {
-    char *variable = strdupz(name);
-    rrdvar_fix_name(variable);
-    uint32_t hash = simple_hash(variable);
-
-    RRDVAR *rv = rrdvar_index_find(&host->variables_root_index, variable, hash);
-    freez(variable);
-
-    if(!rv) {
-        error("Attempted to remove variable '%s' from host '%s', but it does not exist.", name, host->hostname);
-        return;
-    }
-
-    if(rv->type != RRDVAR_TYPE_CALCULATED_ALLOCATED) {
-        error("Attempted to remove variable '%s' from host '%s', but it does not a custom allocated variable.", name, host->hostname);
-        return;
-    }
-
-    if(!rrdvar_index_del(&host->variables_root_index, rv)) {
-        error("Attempted to remove variable '%s' from host '%s', but it cannot be found.", name, host->hostname);
-        return;
-    }
-
-    freez(rv->name);
-    freez(rv->value);
-    freez(rv);
-}
-
-void rrdvar_custom_host_variable_set(RRDVAR *rv, calculated_number value) {
-    if(rv->type != RRDVAR_TYPE_CALCULATED_ALLOCATED)
-        error("requested to set variable '%s' to value " CALCULATED_NUMBER_FORMAT " but the variable is not a custom one.", rv->name, value);
-    else {
-        calculated_number *v = rv->value;
-        *v = value;
-    }
-}
-
-// ----------------------------------------------------------------------------
-// RRDVAR lookup
-
-static calculated_number rrdvar2number(RRDVAR *rv) {
-    switch(rv->type) {
-        case RRDVAR_TYPE_CALCULATED_ALLOCATED:
-        case RRDVAR_TYPE_CALCULATED: {
-            calculated_number *n = (calculated_number *)rv->value;
-            return *n;
-        }
-
-        case RRDVAR_TYPE_TIME_T: {
-            time_t *n = (time_t *)rv->value;
-            return *n;
-        }
-
-        case RRDVAR_TYPE_COLLECTED: {
-            collected_number *n = (collected_number *)rv->value;
-            return *n;
-        }
-
-        case RRDVAR_TYPE_TOTAL: {
-            total_number *n = (total_number *)rv->value;
-            return *n;
-        }
-
-        case RRDVAR_TYPE_INT: {
-            int *n = (int *)rv->value;
-            return *n;
-        }
-
-        default:
-            error("I don't know how to convert RRDVAR type %d to calculated_number", rv->type);
-            return NAN;
-    }
-}
-
-int health_variable_lookup(const char *variable, uint32_t hash, RRDCALC *rc, calculated_number *result) {
-    RRDSET *st = rc->rrdset;
-    RRDVAR *rv;
-
-    if(!st) return 0;
-
-    rv = rrdvar_index_find(&st->variables_root_index, variable, hash);
-    if(rv) {
-        *result = rrdvar2number(rv);
-        return 1;
-    }
-
-    rv = rrdvar_index_find(&st->rrdfamily->variables_root_index, variable, hash);
-    if(rv) {
-        *result = rrdvar2number(rv);
-        return 1;
-    }
-
-    rv = rrdvar_index_find(&st->rrdhost->variables_root_index, variable, hash);
-    if(rv) {
-        *result = rrdvar2number(rv);
-        return 1;
-    }
-
-    return 0;
-}
-
-// ----------------------------------------------------------------------------
-// RRDVAR to JSON
-
-struct variable2json_helper {
-    BUFFER *buf;
-    size_t counter;
-};
-
-static int single_variable2json(void *entry, void *data) {
-    struct variable2json_helper *helper = (struct variable2json_helper *)data;
-    RRDVAR *rv = (RRDVAR *)entry;
-    calculated_number value = rrdvar2number(rv);
-
-    if(unlikely(isnan(value) || isinf(value)))
-        buffer_sprintf(helper->buf, "%s\n\t\t\"%s\": null", helper->counter?",":"", rv->name);
-    else
-        buffer_sprintf(helper->buf, "%s\n\t\t\"%s\": %0.5Lf", helper->counter?",":"", rv->name, (long double)value);
-
-    helper->counter++;
-
-    return 0;
-}
-
-void health_api_v1_chart_variables2json(RRDSET *st, BUFFER *buf) {
-    struct variable2json_helper helper = {
-            .buf = buf,
-            .counter = 0
-    };
-
-    buffer_sprintf(buf, "{\n\t\"chart\": \"%s\",\n\t\"chart_name\": \"%s\",\n\t\"chart_context\": \"%s\",\n\t\"chart_variables\": {", st->id, st->name, st->context);
-    avl_traverse_lock(&st->variables_root_index, single_variable2json, (void *)&helper);
-    buffer_sprintf(buf, "\n\t},\n\t\"family\": \"%s\",\n\t\"family_variables\": {", st->family);
-    helper.counter = 0;
-    avl_traverse_lock(&st->rrdfamily->variables_root_index, single_variable2json, (void *)&helper);
-    buffer_sprintf(buf, "\n\t},\n\t\"host\": \"%s\",\n\t\"host_variables\": {", st->rrdhost->hostname);
-    helper.counter = 0;
-    avl_traverse_lock(&st->rrdhost->variables_root_index, single_variable2json, (void *)&helper);
-    buffer_strcat(buf, "\n\t}\n}\n");
-}
-
-
-// ----------------------------------------------------------------------------
-// RRDDIMVAR management
-// DIMENSION VARIABLES
-
-#define RRDDIMVAR_ID_MAX 1024
-
-static inline void rrddimvar_free_variables(RRDDIMVAR *rs) {
-    RRDDIM *rd = rs->rrddim;
-    RRDSET *st = rd->rrdset;
-
-    // CHART VARIABLES FOR THIS DIMENSION
-
-    rrdvar_free(st->rrdhost, &st->variables_root_index, rs->var_local_id);
-    rs->var_local_id = NULL;
-
-    rrdvar_free(st->rrdhost, &st->variables_root_index, rs->var_local_name);
-    rs->var_local_name = NULL;
-
-    // FAMILY VARIABLES FOR THIS DIMENSION
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family_id);
-    rs->var_family_id = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family_name);
-    rs->var_family_name = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family_contextid);
-    rs->var_family_contextid = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family_contextname);
-    rs->var_family_contextname = NULL;
-
-    // HOST VARIABLES FOR THIS DIMENSION
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host_chartidid);
-    rs->var_host_chartidid = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host_chartidname);
-    rs->var_host_chartidname = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host_chartnameid);
-    rs->var_host_chartnameid = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host_chartnamename);
-    rs->var_host_chartnamename = NULL;
-
-    // KEYS
-
-    freez(rs->key_id);
-    rs->key_id = NULL;
-
-    freez(rs->key_name);
-    rs->key_name = NULL;
-
-    freez(rs->key_fullidid);
-    rs->key_fullidid = NULL;
-
-    freez(rs->key_fullidname);
-    rs->key_fullidname = NULL;
-
-    freez(rs->key_contextid);
-    rs->key_contextid = NULL;
-
-    freez(rs->key_contextname);
-    rs->key_contextname = NULL;
-
-    freez(rs->key_fullnameid);
-    rs->key_fullnameid = NULL;
-
-    freez(rs->key_fullnamename);
-    rs->key_fullnamename = NULL;
-}
-
-static inline void rrddimvar_create_variables(RRDDIMVAR *rs) {
-    rrddimvar_free_variables(rs);
-
-    RRDDIM *rd = rs->rrddim;
-    RRDSET *st = rd->rrdset;
-
-    char buffer[RRDDIMVAR_ID_MAX + 1];
-
-    // KEYS
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s%s%s", rs->prefix, rd->id, rs->suffix);
-    rs->key_id = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s%s%s", rs->prefix, rd->name, rs->suffix);
-    rs->key_name = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->id, rs->key_id);
-    rs->key_fullidid = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->id, rs->key_name);
-    rs->key_fullidname = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->context, rs->key_id);
-    rs->key_contextid = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->context, rs->key_name);
-    rs->key_contextname = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->name, rs->key_id);
-    rs->key_fullnameid = strdupz(buffer);
-
-    snprintfz(buffer, RRDDIMVAR_ID_MAX, "%s.%s", st->name, rs->key_name);
-    rs->key_fullnamename = strdupz(buffer);
-
-    // CHART VARIABLES FOR THIS DIMENSION
-    // -----------------------------------
-    //
-    // dimensions are available as:
-    // - $id
-    // - $name
-
-    rs->var_local_id           = rrdvar_create_and_index("local", &st->variables_root_index, rs->key_id, rs->type, rs->value);
-    rs->var_local_name         = rrdvar_create_and_index("local", &st->variables_root_index, rs->key_name, rs->type, rs->value);
-
-    // FAMILY VARIABLES FOR THIS DIMENSION
-    // -----------------------------------
-    //
-    // dimensions are available as:
-    // - $id                 (only the first, when multiple overlap)
-    // - $name               (only the first, when multiple overlap)
-    // - $chart-context.id
-    // - $chart-context.name
-
-    rs->var_family_id          = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index, rs->key_id, rs->type, rs->value);
-    rs->var_family_name        = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index, rs->key_name, rs->type, rs->value);
-    rs->var_family_contextid   = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index, rs->key_contextid, rs->type, rs->value);
-    rs->var_family_contextname = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index, rs->key_contextname, rs->type, rs->value);
-
-    // HOST VARIABLES FOR THIS DIMENSION
-    // -----------------------------------
-    //
-    // dimensions are available as:
-    // - $chart-id.id
-    // - $chart-id.name
-    // - $chart-name.id
-    // - $chart-name.name
-
-    rs->var_host_chartidid      = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, rs->key_fullidid, rs->type, rs->value);
-    rs->var_host_chartidname    = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, rs->key_fullidname, rs->type, rs->value);
-    rs->var_host_chartnameid    = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, rs->key_fullnameid, rs->type, rs->value);
-    rs->var_host_chartnamename  = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, rs->key_fullnamename, rs->type, rs->value);
-}
-
-RRDDIMVAR *rrddimvar_create(RRDDIM *rd, int type, const char *prefix, const char *suffix, void *value, uint32_t options) {
-    RRDSET *st = rd->rrdset;
-
-    debug(D_VARIABLES, "RRDDIMSET create for chart id '%s' name '%s', dimension id '%s', name '%s%s%s'", st->id, st->name, rd->id, (prefix)?prefix:"", rd->name, (suffix)?suffix:"");
-
-    if(!prefix) prefix = "";
-    if(!suffix) suffix = "";
-
-    RRDDIMVAR *rs = (RRDDIMVAR *)callocz(1, sizeof(RRDDIMVAR));
-
-    rs->prefix = strdupz(prefix);
-    rs->suffix = strdupz(suffix);
-
-    rs->type = type;
-    rs->value = value;
-    rs->options = options;
-    rs->rrddim = rd;
-
-    rs->next = rd->variables;
-    rd->variables = rs;
-
-    rrddimvar_create_variables(rs);
-
-    return rs;
-}
-
-void rrddimvar_rename_all(RRDDIM *rd) {
-    RRDSET *st = rd->rrdset;
-    debug(D_VARIABLES, "RRDDIMSET rename for chart id '%s' name '%s', dimension id '%s', name '%s'", st->id, st->name, rd->id, rd->name);
-
-    RRDDIMVAR *rs, *next = rd->variables;
-    while((rs = next)) {
-        next = rs->next;
-        rrddimvar_create_variables(rs);
-    }
-}
-
-void rrddimvar_free(RRDDIMVAR *rs) {
-    RRDDIM *rd = rs->rrddim;
-    RRDSET *st = rd->rrdset;
-    debug(D_VARIABLES, "RRDDIMSET free for chart id '%s' name '%s', dimension id '%s', name '%s', prefix='%s', suffix='%s'", st->id, st->name, rd->id, rd->name, rs->prefix, rs->suffix);
-
-    rrddimvar_free_variables(rs);
-
-    if(rd->variables == rs) {
-        debug(D_VARIABLES, "RRDDIMSET removing first entry for chart id '%s' name '%s', dimension id '%s', name '%s'", st->id, st->name, rd->id, rd->name);
-        rd->variables = rs->next;
-    }
-    else {
-        debug(D_VARIABLES, "RRDDIMSET removing non-first entry for chart id '%s' name '%s', dimension id '%s', name '%s'", st->id, st->name, rd->id, rd->name);
-        RRDDIMVAR *t;
-        for (t = rd->variables; t && t->next != rs; t = t->next) ;
-        if(!t) error("RRDDIMVAR '%s' not found in dimension '%s/%s' variables linked list", rs->key_name, st->id, rd->id);
-        else t->next = rs->next;
-    }
-
-    freez(rs->prefix);
-    freez(rs->suffix);
-    freez(rs);
-}
-
-// ----------------------------------------------------------------------------
-// RRDSETVAR management
-// CHART VARIABLES
-
-static inline void rrdsetvar_free_variables(RRDSETVAR *rs) {
-    RRDSET *st = rs->rrdset;
-
-    // CHART
-
-    rrdvar_free(st->rrdhost, &st->variables_root_index, rs->var_local);
-    rs->var_local = NULL;
-
-    // FAMILY
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family);
-    rs->var_family = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host);
-    rs->var_host = NULL;
-
-    // HOST
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rs->var_family_name);
-    rs->var_family_name = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rs->var_host_name);
-    rs->var_host_name = NULL;
-
-    // KEYS
-
-    freez(rs->key_fullid);
-    rs->key_fullid = NULL;
-
-    freez(rs->key_fullname);
-    rs->key_fullname = NULL;
-}
-
-static inline void rrdsetvar_create_variables(RRDSETVAR *rs) {
-    rrdsetvar_free_variables(rs);
-
-    RRDSET *st = rs->rrdset;
-
-    // KEYS
-
-    char buffer[RRDVAR_MAX_LENGTH + 1];
-    snprintfz(buffer, RRDVAR_MAX_LENGTH, "%s.%s", st->id, rs->variable);
-    rs->key_fullid = strdupz(buffer);
-
-    snprintfz(buffer, RRDVAR_MAX_LENGTH, "%s.%s", st->name, rs->variable);
-    rs->key_fullname = strdupz(buffer);
-
-    // CHART
-
-    rs->var_local       = rrdvar_create_and_index("local",  &st->variables_root_index,               rs->variable, rs->type, rs->value);
-
-    // FAMILY
-
-    rs->var_family      = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index,    rs->key_fullid,   rs->type, rs->value);
-    rs->var_family_name = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index,    rs->key_fullname, rs->type, rs->value);
-
-    // HOST
-
-    rs->var_host        = rrdvar_create_and_index("host",   &st->rrdhost->variables_root_index,      rs->key_fullid,   rs->type, rs->value);
-    rs->var_host_name   = rrdvar_create_and_index("host",   &st->rrdhost->variables_root_index,      rs->key_fullname, rs->type, rs->value);
-
-}
-
-RRDSETVAR *rrdsetvar_create(RRDSET *st, const char *variable, int type, void *value, uint32_t options) {
-    debug(D_VARIABLES, "RRDVARSET create for chart id '%s' name '%s' with variable name '%s'", st->id, st->name, variable);
-    RRDSETVAR *rs = (RRDSETVAR *)callocz(1, sizeof(RRDSETVAR));
-
-    rs->variable = strdupz(variable);
-    rs->type = type;
-    rs->value = value;
-    rs->options = options;
-    rs->rrdset = st;
-
-    rs->next = st->variables;
-    st->variables = rs;
-
-    rrdsetvar_create_variables(rs);
-
-    return rs;
-}
-
-void rrdsetvar_rename_all(RRDSET *st) {
-    debug(D_VARIABLES, "RRDSETVAR rename for chart id '%s' name '%s'", st->id, st->name);
-
-    RRDSETVAR *rs, *next = st->variables;
-    while((rs = next)) {
-        next = rs->next;
-        rrdsetvar_create_variables(rs);
-    }
-
-    rrdsetcalc_link_matching(st);
-}
-
-void rrdsetvar_free(RRDSETVAR *rs) {
-    RRDSET *st = rs->rrdset;
-    debug(D_VARIABLES, "RRDSETVAR free for chart id '%s' name '%s', variable '%s'", st->id, st->name, rs->variable);
-
-    if(st->variables == rs) {
-        st->variables = rs->next;
-    }
-    else {
-        RRDSETVAR *t;
-        for (t = st->variables; t && t->next != rs; t = t->next);
-        if(!t) error("RRDSETVAR '%s' not found in chart '%s' variables linked list", rs->key_fullname, st->id);
-        else t->next = rs->next;
-    }
-
-    rrdsetvar_free_variables(rs);
-
-    freez(rs->variable);
-    freez(rs);
-}
-
-// ----------------------------------------------------------------------------
-// RRDCALC management
-
-inline const char *rrdcalc_status2string(int status) {
-    switch(status) {
-        case RRDCALC_STATUS_REMOVED:
-            return "REMOVED";
-
-        case RRDCALC_STATUS_UNDEFINED:
-            return "UNDEFINED";
-
-        case RRDCALC_STATUS_UNINITIALIZED:
-            return "UNINITIALIZED";
-
-        case RRDCALC_STATUS_CLEAR:
-            return "CLEAR";
-
-        case RRDCALC_STATUS_RAISED:
-            return "RAISED";
-
-        case RRDCALC_STATUS_WARNING:
-            return "WARNING";
-
-        case RRDCALC_STATUS_CRITICAL:
-            return "CRITICAL";
-
-        default:
-            error("Unknown alarm status %d", status);
-            return "UNKNOWN";
-    }
-}
-
-static void rrdsetcalc_link(RRDSET *st, RRDCALC *rc) {
-    debug(D_HEALTH, "Health linking alarm '%s.%s' to chart '%s' of host '%s'", rc->chart?rc->chart:"NOCHART", rc->name, st->id, st->rrdhost->hostname);
-
-    rc->last_status_change = now_realtime_sec();
-    rc->rrdset = st;
-
-    rc->rrdset_next = st->alarms;
-    rc->rrdset_prev = NULL;
-    
-    if(rc->rrdset_next)
-        rc->rrdset_next->rrdset_prev = rc;
-
-    st->alarms = rc;
-
-    if(rc->update_every < rc->rrdset->update_every) {
-        error("Health alarm '%s.%s' has update every %d, less than chart update every %d. Setting alarm update frequency to %d.", rc->rrdset->id, rc->name, rc->update_every, rc->rrdset->update_every, rc->rrdset->update_every);
-        rc->update_every = rc->rrdset->update_every;
-    }
-
-    if(!isnan(rc->green) && isnan(st->green)) {
-        debug(D_HEALTH, "Health alarm '%s.%s' green threshold set from %Lf to %Lf.", rc->rrdset->id, rc->name, rc->rrdset->green, rc->green);
-        st->green = rc->green;
-    }
-
-    if(!isnan(rc->red) && isnan(st->red)) {
-        debug(D_HEALTH, "Health alarm '%s.%s' red threshold set from %Lf to %Lf.", rc->rrdset->id, rc->name, rc->rrdset->red, rc->red);
-        st->red = rc->red;
-    }
-
-    rc->local  = rrdvar_create_and_index("local",  &st->variables_root_index, rc->name, RRDVAR_TYPE_CALCULATED, &rc->value);
-    rc->family = rrdvar_create_and_index("family", &st->rrdfamily->variables_root_index, rc->name, RRDVAR_TYPE_CALCULATED, &rc->value);
-
-    char fullname[RRDVAR_MAX_LENGTH + 1];
-    snprintfz(fullname, RRDVAR_MAX_LENGTH, "%s.%s", st->id, rc->name);
-    rc->hostid   = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, fullname, RRDVAR_TYPE_CALCULATED, &rc->value);
-
-    snprintfz(fullname, RRDVAR_MAX_LENGTH, "%s.%s", st->name, rc->name);
-    rc->hostname = rrdvar_create_and_index("host", &st->rrdhost->variables_root_index, fullname, RRDVAR_TYPE_CALCULATED, &rc->value);
-
-	if(!rc->units) rc->units = strdupz(st->units);
-
-    {
-        time_t now = now_realtime_sec();
-        health_alarm_log(
-                st->rrdhost,
-                rc->id,
-                rc->next_event_id++,
-                now,
-                rc->name,
-                rc->rrdset->id,
-                rc->rrdset->family,
-                rc->exec,
-                rc->recipient,
-                now - rc->last_status_change,
-                rc->old_value,
-                rc->value,
-                rc->status,
-                RRDCALC_STATUS_UNINITIALIZED,
-                rc->source,
-                rc->units,
-                rc->info,
-                0,
-                0
-        );
-    }
-}
-
-static inline int rrdcalc_is_matching_this_rrdset(RRDCALC *rc, RRDSET *st) {
-    if(     (rc->hash_chart == st->hash      && !strcmp(rc->chart, st->id)) ||
-            (rc->hash_chart == st->hash_name && !strcmp(rc->chart, st->name)))
-        return 1;
-
-    return 0;
-}
-
-// this has to be called while the RRDHOST is locked
-inline void rrdsetcalc_link_matching(RRDSET *st) {
-    // debug(D_HEALTH, "find matching alarms for chart '%s'", st->id);
-
-    RRDCALC *rc;
-    for(rc = st->rrdhost->alarms; rc ; rc = rc->next) {
-        if(unlikely(rc->rrdset))
-            continue;
-
-        if(unlikely(rrdcalc_is_matching_this_rrdset(rc, st)))
-            rrdsetcalc_link(st, rc);
-    }
-}
-
-// this has to be called while the RRDHOST is locked
-inline void rrdsetcalc_unlink(RRDCALC *rc) {
-    RRDSET *st = rc->rrdset;
-
-    if(!st) {
-        debug(D_HEALTH, "Requested to unlink RRDCALC '%s.%s' which is not linked to any RRDSET", rc->chart?rc->chart:"NOCHART", rc->name);
-        error("Requested to unlink RRDCALC '%s.%s' which is not linked to any RRDSET", rc->chart?rc->chart:"NOCHART", rc->name);
-        return;
-    }
-
-    {
-        time_t now = now_realtime_sec();
-        health_alarm_log(
-                st->rrdhost,
-                rc->id,
-                rc->next_event_id++,
-                now,
-                rc->name,
-                rc->rrdset->id,
-                rc->rrdset->family,
-                rc->exec,
-                rc->recipient,
-                now - rc->last_status_change,
-                rc->old_value,
-                rc->value,
-                rc->status,
-                RRDCALC_STATUS_REMOVED,
-                rc->source,
-                rc->units,
-                rc->info,
-                0,
-                0
-        );
-    }
-
-    RRDHOST *host = st->rrdhost;
-
-    debug(D_HEALTH, "Health unlinking alarm '%s.%s' from chart '%s' of host '%s'", rc->chart?rc->chart:"NOCHART", rc->name, st->id, host->hostname);
-
-    // unlink it
-    if(rc->rrdset_prev)
-        rc->rrdset_prev->rrdset_next = rc->rrdset_next;
-
-    if(rc->rrdset_next)
-        rc->rrdset_next->rrdset_prev = rc->rrdset_prev;
-
-    if(st->alarms == rc)
-        st->alarms = rc->rrdset_next;
-
-    rc->rrdset_prev = rc->rrdset_next = NULL;
-
-    rrdvar_free(st->rrdhost, &st->variables_root_index, rc->local);
-    rc->local = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdfamily->variables_root_index, rc->family);
-    rc->family = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rc->hostid);
-    rc->hostid = NULL;
-
-    rrdvar_free(st->rrdhost, &st->rrdhost->variables_root_index, rc->hostname);
-    rc->hostname = NULL;
-
-    rc->rrdset = NULL;
-
-    // RRDCALC will remain in RRDHOST
-    // so that if the matching chart is found in the future
-    // it will be applied automatically
-}
-
-RRDCALC *rrdcalc_find(RRDSET *st, const char *name) {
-    RRDCALC *rc;
-    uint32_t hash = simple_hash(name);
-
-    for( rc = st->alarms; rc ; rc = rc->rrdset_next ) {
-        if(unlikely(rc->hash == hash && !strcmp(rc->name, name)))
-            return rc;
-    }
-
-    return NULL;
-}
-
-inline int rrdcalc_exists(RRDHOST *host, const char *chart, const char *name, uint32_t hash_chart, uint32_t hash_name) {
-    RRDCALC *rc;
-
-    if(unlikely(!chart)) {
-        error("attempt to find RRDCALC '%s' without giving a chart name", name);
-        return 1;
-    }
-
-    if(unlikely(!hash_chart)) hash_chart = simple_hash(chart);
-    if(unlikely(!hash_name))  hash_name  = simple_hash(name);
-
-    // make sure it does not already exist
-    for(rc = host->alarms; rc ; rc = rc->next) {
-        if (unlikely(rc->chart && rc->hash == hash_name && rc->hash_chart == hash_chart && !strcmp(name, rc->name) && !strcmp(chart, rc->chart))) {
-            debug(D_HEALTH, "Health alarm '%s.%s' already exists in host '%s'.", chart, name, host->hostname);
-            error("Health alarm '%s.%s' already exists in host '%s'.", chart, name, host->hostname);
-            return 1;
-        }
-    }
-
-    return 0;
-}
-
-inline uint32_t rrdcalc_get_unique_id(RRDHOST *host, const char *chart, const char *name, uint32_t *next_event_id) {
-    if(chart && name) {
-        uint32_t hash_chart = simple_hash(chart);
-        uint32_t hash_name = simple_hash(name);
-
-        // re-use old IDs, by looking them up in the alarm log
-        ALARM_ENTRY *ae;
-        for(ae = host->health_log.alarms; ae ;ae = ae->next) {
-            if(unlikely(ae->hash_name == hash_name && ae->hash_chart == hash_chart && !strcmp(name, ae->name) && !strcmp(chart, ae->chart))) {
-                if(next_event_id) *next_event_id = ae->alarm_event_id + 1;
-                return ae->alarm_id;
-            }
-        }
-    }
-
-    return host->health_log.next_alarm_id++;
-}
-
-inline void rrdcalc_create_part2(RRDHOST *host, RRDCALC *rc) {
-    rrdhost_check_rdlock(host);
-
-    if(rc->calculation) {
-        rc->calculation->status = &rc->status;
-        rc->calculation->this = &rc->value;
-        rc->calculation->after = &rc->db_after;
-        rc->calculation->before = &rc->db_before;
-        rc->calculation->rrdcalc = rc;
-    }
-
-    if(rc->warning) {
-        rc->warning->status = &rc->status;
-        rc->warning->this = &rc->value;
-        rc->warning->after = &rc->db_after;
-        rc->warning->before = &rc->db_before;
-        rc->warning->rrdcalc = rc;
-    }
-
-    if(rc->critical) {