Adding upstream version 1.37.1.upstream/1.37.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1183 insertions, 0 deletions

diff --git a/database/rrdlabels.c b/database/rrdlabels.c
new file mode 100644
index 0000000..743499a
--- /dev/null
+++ b/database/rrdlabels.c
@@ -0,0 +1,1183 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#define NETDATA_RRD_INTERNALS
+#include "rrd.h"
+
+// ----------------------------------------------------------------------------
+// labels sanitization
+
+/*
+ * All labels follow these rules:
+ *
+ * Character           Symbol               Values     Names
+ * UTF-8 characters    UTF-8                yes        -> _
+ * Lower case letter   [a-z]                yes        yes
+ * Upper case letter   [A-Z]                yes        -> [a-z]
+ * Digit               [0-9]                yes        yes
+ * Underscore          _                    yes        yes
+ * Minus               -                    yes        yes
+ * Plus                +                    yes        -> _
+ * Colon               :                    yes        -> _
+ * Semicolon           ;                    -> :       -> _
+ * Equal               =                    -> :       -> _
+ * Period              .                    yes        yes
+ * Comma               ,                    -> .       -> .
+ * Slash               /                    yes        yes
+ * Backslash           \                    -> /       -> /
+ * At                  @                    yes        -> _
+ * Space                                    yes        -> _
+ * Opening parenthesis (                    yes        -> _
+ * Closing parenthesis )                    yes        -> _
+ * anything else                            -> _       -> _
+*
+ * The above rules should allow users to set in tags (indicative):
+ *
+ * 1. hostnames and domain names as-is
+ * 2. email addresses as-is
+ * 3. floating point numbers, converted to always use a dot as the decimal point
+ *
+ * Leading and trailing spaces and control characters are removed from both label
+ * names and values.
+ *
+ * Multiple spaces inside the label name or the value are removed (only 1 is retained).
+ * In names spaces are also converted to underscores.
+ *
+ * Names that are only underscores are rejected (they do not enter the dictionary).
+ *
+ * The above rules do not require any conversion to be included in JSON strings.
+ *
+ * Label names and values are truncated to LABELS_MAX_LENGTH (200) characters.
+ *
+ * When parsing, label key and value are separated by the first colon (:) found.
+ * So label:value1:value2 is parsed as key = "label", value = "value1:value2"
+ *
+ * This means a label key cannot contain a colon (:) - it is converted to
+ * underscore if it does.
+ *
+ */
+
+#define RRDLABELS_MAX_NAME_LENGTH 200
+#define RRDLABELS_MAX_VALUE_LENGTH 800 // 800 in bytes, up to 200 UTF-8 characters
+
+static unsigned char label_spaces_char_map[256];
+static unsigned char label_names_char_map[256];
+static unsigned char label_values_char_map[256] = {
+    [0] = '\0', //
+    [1] = '_', //
+    [2] = '_', //
+    [3] = '_', //
+    [4] = '_', //
+    [5] = '_', //
+    [6] = '_', //
+    [7] = '_', //
+    [8] = '_', //
+    [9] = '_', //
+    [10] = '_', //
+    [11] = '_', //
+    [12] = '_', //
+    [13] = '_', //
+    [14] = '_', //
+    [15] = '_', //
+    [16] = '_', //
+    [17] = '_', //
+    [18] = '_', //
+    [19] = '_', //
+    [20] = '_', //
+    [21] = '_', //
+    [22] = '_', //
+    [23] = '_', //
+    [24] = '_', //
+    [25] = '_', //
+    [26] = '_', //
+    [27] = '_', //
+    [28] = '_', //
+    [29] = '_', //
+    [30] = '_', //
+    [31] = '_', //
+    [32] = ' ', // SPACE keep
+    [33] = '_', // !
+    [34] = '_', // "
+    [35] = '_', // #
+    [36] = '_', // $
+    [37] = '_', // %
+    [38] = '_', // &
+    [39] = '_', // '
+    [40] = '(', // ( keep
+    [41] = ')', // ) keep
+    [42] = '_', // *
+    [43] = '+', // + keep
+    [44] = '.', // , convert , to .
+    [45] = '-', // - keep
+    [46] = '.', // . keep
+    [47] = '/', // / keep
+    [48] = '0', // 0 keep
+    [49] = '1', // 1 keep
+    [50] = '2', // 2 keep
+    [51] = '3', // 3 keep
+    [52] = '4', // 4 keep
+    [53] = '5', // 5 keep
+    [54] = '6', // 6 keep
+    [55] = '7', // 7 keep
+    [56] = '8', // 8 keep
+    [57] = '9', // 9 keep
+    [58] = ':', // : keep
+    [59] = ':', // ; convert ; to :
+    [60] = '_', // <
+    [61] = ':', // = convert = to :
+    [62] = '_', // >
+    [63] = '_', // ?
+    [64] = '@', // @
+    [65] = 'A', // A keep
+    [66] = 'B', // B keep
+    [67] = 'C', // C keep
+    [68] = 'D', // D keep
+    [69] = 'E', // E keep
+    [70] = 'F', // F keep
+    [71] = 'G', // G keep
+    [72] = 'H', // H keep
+    [73] = 'I', // I keep
+    [74] = 'J', // J keep
+    [75] = 'K', // K keep
+    [76] = 'L', // L keep
+    [77] = 'M', // M keep
+    [78] = 'N', // N keep
+    [79] = 'O', // O keep
+    [80] = 'P', // P keep
+    [81] = 'Q', // Q keep
+    [82] = 'R', // R keep
+    [83] = 'S', // S keep
+    [84] = 'T', // T keep
+    [85] = 'U', // U keep
+    [86] = 'V', // V keep
+    [87] = 'W', // W keep
+    [88] = 'X', // X keep
+    [89] = 'Y', // Y keep
+    [90] = 'Z', // Z keep
+    [91] = '_', // [
+    [92] = '/', // backslash convert \ to /
+    [93] = '_', // ]
+    [94] = '_', // ^
+    [95] = '_', // _ keep
+    [96] = '_', // `
+    [97] = 'a', // a keep
+    [98] = 'b', // b keep
+    [99] = 'c', // c keep
+    [100] = 'd', // d keep
+    [101] = 'e', // e keep
+    [102] = 'f', // f keep
+    [103] = 'g', // g keep
+    [104] = 'h', // h keep
+    [105] = 'i', // i keep
+    [106] = 'j', // j keep
+    [107] = 'k', // k keep
+    [108] = 'l', // l keep
+    [109] = 'm', // m keep
+    [110] = 'n', // n keep
+    [111] = 'o', // o keep
+    [112] = 'p', // p keep
+    [113] = 'q', // q keep
+    [114] = 'r', // r keep
+    [115] = 's', // s keep
+    [116] = 't', // t keep
+    [117] = 'u', // u keep
+    [118] = 'v', // v keep
+    [119] = 'w', // w keep
+    [120] = 'x', // x keep
+    [121] = 'y', // y keep
+    [122] = 'z', // z keep
+    [123] = '_', // {
+    [124] = '_', // |
+    [125] = '_', // }
+    [126] = '_', // ~
+    [127] = '_', //
+    [128] = '_', //
+    [129] = '_', //
+    [130] = '_', //
+    [131] = '_', //
+    [132] = '_', //
+    [133] = '_', //
+    [134] = '_', //
+    [135] = '_', //
+    [136] = '_', //
+    [137] = '_', //
+    [138] = '_', //
+    [139] = '_', //
+    [140] = '_', //
+    [141] = '_', //
+    [142] = '_', //
+    [143] = '_', //
+    [144] = '_', //
+    [145] = '_', //
+    [146] = '_', //
+    [147] = '_', //
+    [148] = '_', //
+    [149] = '_', //
+    [150] = '_', //
+    [151] = '_', //
+    [152] = '_', //
+    [153] = '_', //
+    [154] = '_', //
+    [155] = '_', //
+    [156] = '_', //
+    [157] = '_', //
+    [158] = '_', //
+    [159] = '_', //
+    [160] = '_', //
+    [161] = '_', //
+    [162] = '_', //
+    [163] = '_', //
+    [164] = '_', //
+    [165] = '_', //
+    [166] = '_', //
+    [167] = '_', //
+    [168] = '_', //
+    [169] = '_', //
+    [170] = '_', //
+    [171] = '_', //
+    [172] = '_', //
+    [173] = '_', //
+    [174] = '_', //
+    [175] = '_', //
+    [176] = '_', //
+    [177] = '_', //
+    [178] = '_', //
+    [179] = '_', //
+    [180] = '_', //
+    [181] = '_', //
+    [182] = '_', //
+    [183] = '_', //
+    [184] = '_', //
+    [185] = '_', //
+    [186] = '_', //
+    [187] = '_', //
+    [188] = '_', //
+    [189] = '_', //
+    [190] = '_', //
+    [191] = '_', //
+    [192] = '_', //
+    [193] = '_', //
+    [194] = '_', //
+    [195] = '_', //
+    [196] = '_', //
+    [197] = '_', //
+    [198] = '_', //
+    [199] = '_', //
+    [200] = '_', //
+    [201] = '_', //
+    [202] = '_', //
+    [203] = '_', //
+    [204] = '_', //
+    [205] = '_', //
+    [206] = '_', //
+    [207] = '_', //
+    [208] = '_', //
+    [209] = '_', //
+    [210] = '_', //
+    [211] = '_', //
+    [212] = '_', //
+    [213] = '_', //
+    [214] = '_', //
+    [215] = '_', //
+    [216] = '_', //
+    [217] = '_', //
+    [218] = '_', //
+    [219] = '_', //
+    [220] = '_', //
+    [221] = '_', //
+    [222] = '_', //
+    [223] = '_', //
+    [224] = '_', //
+    [225] = '_', //
+    [226] = '_', //
+    [227] = '_', //
+    [228] = '_', //
+    [229] = '_', //
+    [230] = '_', //
+    [231] = '_', //
+    [232] = '_', //
+    [233] = '_', //
+    [234] = '_', //
+    [235] = '_', //
+    [236] = '_', //
+    [237] = '_', //
+    [238] = '_', //
+    [239] = '_', //
+    [240] = '_', //
+    [241] = '_', //
+    [242] = '_', //
+    [243] = '_', //
+    [244] = '_', //
+    [245] = '_', //
+    [246] = '_', //
+    [247] = '_', //
+    [248] = '_', //
+    [249] = '_', //
+    [250] = '_', //
+    [251] = '_', //
+    [252] = '_', //
+    [253] = '_', //
+    [254] = '_', //
+    [255] = '_'  //
+};
+
+__attribute__((constructor)) void initialize_labels_keys_char_map(void) {
+    // copy the values char map to the names char map
+    size_t i;
+    for(i = 0; i < 256 ;i++)
+        label_names_char_map[i] = label_values_char_map[i];
+
+    // apply overrides to the label names map
+    label_names_char_map['A'] = 'a';
+    label_names_char_map['B'] = 'b';
+    label_names_char_map['C'] = 'c';
+    label_names_char_map['D'] = 'd';
+    label_names_char_map['E'] = 'e';
+    label_names_char_map['F'] = 'f';
+    label_names_char_map['G'] = 'g';
+    label_names_char_map['H'] = 'h';
+    label_names_char_map['I'] = 'i';
+    label_names_char_map['J'] = 'j';
+    label_names_char_map['K'] = 'k';
+    label_names_char_map['L'] = 'l';
+    label_names_char_map['M'] = 'm';
+    label_names_char_map['N'] = 'n';
+    label_names_char_map['O'] = 'o';
+    label_names_char_map['P'] = 'p';
+    label_names_char_map['Q'] = 'q';
+    label_names_char_map['R'] = 'r';
+    label_names_char_map['S'] = 's';
+    label_names_char_map['T'] = 't';
+    label_names_char_map['U'] = 'u';
+    label_names_char_map['V'] = 'v';
+    label_names_char_map['W'] = 'w';
+    label_names_char_map['X'] = 'x';
+    label_names_char_map['Y'] = 'y';
+    label_names_char_map['Z'] = 'z';
+    label_names_char_map['='] = '_';
+    label_names_char_map[':'] = '_';
+    label_names_char_map['+'] = '_';
+    label_names_char_map[';'] = '_';
+    label_names_char_map['@'] = '_';
+    label_names_char_map['('] = '_';
+    label_names_char_map[')'] = '_';
+    label_names_char_map[' '] = '_';
+    label_names_char_map['\\'] = '/';
+
+    // create the spaces map
+    for(i = 0; i < 256 ;i++)
+        label_spaces_char_map[i] = (isspace(i) || iscntrl(i) || !isprint(i))?1:0;
+
+}
+
+size_t text_sanitize(unsigned char *dst, const unsigned char *src, size_t dst_size, unsigned char *char_map, bool utf, const char *empty, size_t *multibyte_length) {
+    if(unlikely(!dst_size)) return 0;
+
+    if(unlikely(!src || !*src)) {
+        strncpyz((char *)dst, empty, dst_size);
+        dst[dst_size - 1] = '\0';
+        size_t len = strlen((char *)dst);
+        if(multibyte_length) *multibyte_length = len;
+        return len;
+    }
+
+    unsigned char *d = dst;
+
+    // make room for the final string termination
+    unsigned char *end = &d[dst_size - 1];
+
+    // copy while converting, but keep only one white space
+    // we start wil last_is_space = 1 to skip leading spaces
+    int last_is_space = 1;
+
+    size_t mblen = 0;
+
+    while(*src && d < end) {
+        unsigned char c = *src;
+
+        if(IS_UTF8_STARTBYTE(c) && IS_UTF8_BYTE(src[1]) && d + 2 < end) {
+            // UTF-8 multi-byte encoded character
+
+            // find how big this character is (2-4 bytes)
+            size_t utf_character_size = 2;
+            while(utf_character_size <= 4 && src[utf_character_size] && IS_UTF8_BYTE(src[utf_character_size]) && !IS_UTF8_STARTBYTE(src[utf_character_size]))
+                utf_character_size++;
+
+            if(utf) {
+                while(utf_character_size) {
+                    utf_character_size--;
+                    *d++ = *src++;
+                }
+            }
+            else {
+                // UTF-8 characters are not allowed.
+                // Assume it is an underscore
+                // and skip all except the first byte
+                *d++ = '_';
+                src += (utf_character_size - 1);
+            }
+
+            last_is_space = 0;
+            mblen++;
+            continue;
+        }
+
+        if(label_spaces_char_map[c]) {
+            // a space character
+
+            if(!last_is_space) {
+                // add one space
+                *d++ = char_map[c];
+                mblen++;
+            }
+
+            last_is_space++;
+        }
+        else {
+            *d++ = char_map[c];
+            last_is_space = 0;
+            mblen++;
+        }
+
+        src++;
+    }
+
+    // remove the last trailing space
+    if(last_is_space && d > dst) {
+        d--;
+        mblen--;
+    }
+
+    // put a termination at the end of what we copied
+    *d = '\0';
+
+    // check if dst is all underscores and empty it if it is
+    if(*dst == '_') {
+        unsigned char *t = dst;
+        while (*t == '_') t++;
+        if (unlikely(*t == '\0')) {
+            *dst = '\0';
+            mblen = 0;
+        }
+    }
+
+    if(unlikely(*dst == '\0')) {
+        strncpyz((char *)dst, empty, dst_size);
+        dst[dst_size - 1] = '\0';
+        mblen = strlen((char *)dst);
+        if(multibyte_length) *multibyte_length = mblen;
+        return mblen;
+    }
+
+    if(multibyte_length) *multibyte_length = mblen;
+
+    return d - dst;
+}
+
+static inline size_t rrdlabels_sanitize_name(char *dst, const char *src, size_t dst_size) {
+    return text_sanitize((unsigned char *)dst, (const unsigned char *)src, dst_size, label_names_char_map, 0, "", NULL);
+}
+
+static inline size_t rrdlabels_sanitize_value(char *dst, const char *src, size_t dst_size) {
+    return text_sanitize((unsigned char *)dst, (const unsigned char *)src, dst_size, label_values_char_map, 1, "[none]", NULL);
+}
+
+// ----------------------------------------------------------------------------
+// rrdlabels_create()
+
+typedef struct rrdlabel {
+    STRING *label_value;
+    RRDLABEL_SRC label_source;
+} RRDLABEL;
+
+static void rrdlabel_insert_callback(const DICTIONARY_ITEM *item __maybe_unused, void *value, void *dict_ptr __maybe_unused) {
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    // label_value is already allocated by the STRING
+    lb->label_source |=  RRDLABEL_FLAG_NEW;
+    lb->label_source &= ~RRDLABEL_FLAG_OLD;
+}
+
+static void rrdlabel_delete_callback(const DICTIONARY_ITEM *item __maybe_unused, void *value, void *dict_ptr __maybe_unused) {
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    string_freez(lb->label_value);
+    lb->label_value = NULL;
+}
+
+static bool rrdlabel_conflict_callback(const DICTIONARY_ITEM *item __maybe_unused, void *oldvalue, void *newvalue, void *dict_ptr __maybe_unused) {
+    RRDLABEL *lbold = (RRDLABEL *)oldvalue;
+    RRDLABEL *lbnew = (RRDLABEL *)newvalue;
+
+    if(lbold->label_value == lbnew->label_value) {
+        // they are the same
+
+        lbold->label_source |=  lbnew->label_source;
+        lbold->label_source |=  RRDLABEL_FLAG_OLD;
+        lbold->label_source &= ~RRDLABEL_FLAG_NEW;
+
+        // free the new one
+        string_freez(lbnew->label_value);
+
+        return false;
+    }
+
+    // they are different
+
+    string_freez(lbold->label_value);
+    lbold->label_value  =   lbnew->label_value;
+    lbold->label_source =   lbnew->label_source;
+    lbold->label_source |=  RRDLABEL_FLAG_NEW;
+    lbold->label_source &= ~RRDLABEL_FLAG_OLD;
+
+    return true;
+}
+
+DICTIONARY *rrdlabels_create(void) {
+    DICTIONARY *dict = dictionary_create(DICT_OPTION_DONT_OVERWRITE_VALUE);
+    dictionary_register_insert_callback(dict, rrdlabel_insert_callback, dict);
+    dictionary_register_delete_callback(dict, rrdlabel_delete_callback, dict);
+    dictionary_register_conflict_callback(dict, rrdlabel_conflict_callback, dict);
+    return dict;
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_destroy()
+
+void rrdlabels_destroy(DICTIONARY *labels_dict) {
+    dictionary_destroy(labels_dict);
+}
+
+void rrdlabels_flush(DICTIONARY *labels_dict) {
+    dictionary_flush(labels_dict);
+}
+
+// ----------------------------------------------------------------------------
+// rrdlabels_add()
+
+static void labels_add_already_sanitized(DICTIONARY *dict, const char *key, const char *value, RRDLABEL_SRC ls) {
+    if(ls & RRDLABEL_FLAG_NEW) ls &= ~RRDLABEL_FLAG_NEW;
+    if(ls & RRDLABEL_FLAG_OLD) ls &= ~RRDLABEL_FLAG_OLD;
+
+    RRDLABEL tmp = {
+        .label_source = ls,
+        .label_value = string_strdupz(value)
+    };
+    dictionary_set(dict, key, &tmp, sizeof(RRDLABEL));
+}
+
+
+void rrdlabels_add(DICTIONARY *dict, const char *name, const char *value, RRDLABEL_SRC ls) {
+    if(!dict) {
+        error("%s(): called with NULL dictionary.", __FUNCTION__ );
+        return;
+    }
+
+    char n[RRDLABELS_MAX_NAME_LENGTH + 1], v[RRDLABELS_MAX_VALUE_LENGTH + 1];
+    rrdlabels_sanitize_name(n, name, RRDLABELS_MAX_NAME_LENGTH);
+    rrdlabels_sanitize_value(v, value, RRDLABELS_MAX_VALUE_LENGTH);
+
+    if(!*n) {
+        error("%s: cannot add name '%s' (value '%s') which is sanitized as empty string", __FUNCTION__, name, value);
+        return;
+    }
+
+    labels_add_already_sanitized(dict, n, v, ls);
+}
+
+static const char *get_quoted_string_up_to(char *dst, size_t dst_size, const char *string, char upto1, char upto2) {
+    size_t len = 0;
+    char *d = dst, quote = 0;
+    while(*string && len++ < dst_size) {
+        if(unlikely(!quote && (*string == '\'' || *string == '"'))) {
+            quote = *string++;
+            continue;
+        }
+
+        if(unlikely(quote && *string == quote)) {
+            quote = 0;
+            string++;
+            continue;
+        }
+
+        if(unlikely(quote && *string == '\\' && string[1])) {
+            string++;
+            *d++ = *string++;
+            continue;
+        }
+
+        if(unlikely(!quote && (*string == upto1 || *string == upto2))) break;
+
+        *d++ = *string++;
+    }
+    *d = '\0';
+
+    if(*string) string++;
+
+    return string;
+}
+
+void rrdlabels_add_pair(DICTIONARY *dict, const char *string, RRDLABEL_SRC ls) {
+    if(!dict) {
+        error("%s(): called with NULL dictionary.", __FUNCTION__ );
+        return;
+    }
+
+    char name[RRDLABELS_MAX_NAME_LENGTH + 1];
+    string = get_quoted_string_up_to(name, RRDLABELS_MAX_NAME_LENGTH, string, '=', ':');
+
+    char value[RRDLABELS_MAX_VALUE_LENGTH + 1];
+    get_quoted_string_up_to(value, RRDLABELS_MAX_VALUE_LENGTH, string, '\0', '\0');
+
+    rrdlabels_add(dict, name, value, ls);
+}
+
+// ----------------------------------------------------------------------------
+// rrdlabels_get_value_to_buffer_or_null()
+
+void rrdlabels_get_value_to_buffer_or_null(DICTIONARY *labels, BUFFER *wb, const char *key, const char *quote, const char *null) {
+    if(!labels) return;
+
+    const DICTIONARY_ITEM *acquired_item = dictionary_get_and_acquire_item(labels, key);
+    RRDLABEL *lb = dictionary_acquired_item_value(acquired_item);
+
+    if(lb && lb->label_value)
+        buffer_sprintf(wb, "%s%s%s", quote, string2str(lb->label_value), quote);
+    else
+        buffer_strcat(wb, null);
+
+    dictionary_acquired_item_release(labels, acquired_item);
+}
+
+// ----------------------------------------------------------------------------
+// rrdlabels_get_value_to_char_or_null()
+
+void rrdlabels_get_value_to_char_or_null(DICTIONARY *labels, char **value, const char *key) {
+    const DICTIONARY_ITEM *acquired_item = dictionary_get_and_acquire_item(labels, key);
+    RRDLABEL *lb = dictionary_acquired_item_value(acquired_item);
+
+    *value = (lb && lb->label_value) ? strdupz(string2str(lb->label_value)) : NULL;
+
+    dictionary_acquired_item_release(labels, acquired_item);
+}
+
+// ----------------------------------------------------------------------------
+// rrdlabels_unmark_all()
+// remove labels RRDLABEL_FLAG_OLD and RRDLABEL_FLAG_NEW from all dictionary items
+
+static int remove_flags_old_new(const DICTIONARY_ITEM *item __maybe_unused, void *value, void *data __maybe_unused) {
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    if(lb->label_source & RRDLABEL_FLAG_OLD) lb->label_source &= ~RRDLABEL_FLAG_OLD;
+    if(lb->label_source & RRDLABEL_FLAG_NEW) lb->label_source &= ~RRDLABEL_FLAG_NEW;
+
+    return 1;
+}
+
+void rrdlabels_unmark_all(DICTIONARY *labels) {
+    dictionary_walkthrough_read(labels, remove_flags_old_new, NULL);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_remove_all_unmarked()
+// remove dictionary items that are neither old, nor new
+
+static int remove_not_old_not_new_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    DICTIONARY *dict = (DICTIONARY *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    if(!(lb->label_source & (RRDLABEL_FLAG_OLD | RRDLABEL_FLAG_NEW | RRDLABEL_FLAG_PERMANENT))) {
+        dictionary_del(dict, name);
+        return 1;
+    }
+
+    return 0;
+}
+
+void rrdlabels_remove_all_unmarked(DICTIONARY *labels) {
+    dictionary_walkthrough_write(labels, remove_not_old_not_new_callback, labels);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_walkthrough_read()
+
+struct labels_walkthrough {
+    int (*callback)(const char *name, const char *value, RRDLABEL_SRC ls, void *data);
+    void *data;
+};
+
+static int labels_walkthrough_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    struct labels_walkthrough *d = (struct labels_walkthrough *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    RRDLABEL_SRC ls = lb->label_source;
+    if(ls & RRDLABEL_FLAG_NEW) ls &= ~RRDLABEL_FLAG_NEW;
+    if(ls & RRDLABEL_FLAG_OLD) ls &= ~RRDLABEL_FLAG_OLD;
+
+    return d->callback(name, string2str(lb->label_value), ls, d->data);
+}
+
+int rrdlabels_walkthrough_read(DICTIONARY *labels, int (*callback)(const char *name, const char *value, RRDLABEL_SRC ls, void *data), void *data) {
+    struct labels_walkthrough d = {
+        .callback = callback,
+        .data = data
+    };
+    return dictionary_walkthrough_read(labels, labels_walkthrough_callback, &d);
+}
+
+int rrdlabels_sorted_walkthrough_read(DICTIONARY *labels, int (*callback)(const char *name, const char *value, RRDLABEL_SRC ls, void *data), void *data) {
+    struct labels_walkthrough d = {
+        .callback = callback,
+        .data = data
+    };
+    return dictionary_sorted_walkthrough_read(labels, labels_walkthrough_callback, &d);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_migrate_to_these()
+// migrate an existing label list to a new list, INPLACE
+
+static int copy_label_to_dictionary_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    DICTIONARY *dst = (DICTIONARY *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+    labels_add_already_sanitized(dst, name, string2str(lb->label_value), lb->label_source);
+    return 1;
+}
+
+void rrdlabels_migrate_to_these(DICTIONARY *dst, DICTIONARY *src) {
+    if(!dst || !src) return;
+
+    // remove the RRDLABEL_FLAG_OLD and RRDLABEL_FLAG_NEW from all items
+    rrdlabels_unmark_all(dst);
+
+    // Mark the existing ones as RRDLABEL_FLAG_OLD,
+    // or the newly added ones as RRDLABEL_FLAG_NEW
+    dictionary_walkthrough_read(src, copy_label_to_dictionary_callback, dst);
+
+    // remove the unmarked dst
+    rrdlabels_remove_all_unmarked(dst);
+}
+
+void rrdlabels_copy(DICTIONARY *dst, DICTIONARY *src) {
+    if(!dst || !src) return;
+
+    dictionary_walkthrough_read(src, copy_label_to_dictionary_callback, dst);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_match_simple_pattern()
+// returns true when there are keys in the dictionary matching a simple pattern
+
+struct simple_pattern_match_name_value {
+    SIMPLE_PATTERN *pattern;
+    char equal;
+};
+
+static int simple_pattern_match_name_only_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    struct simple_pattern_match_name_value *t = (struct simple_pattern_match_name_value *)data;
+    (void)value;
+
+    // we return -1 to stop the walkthrough on first match
+    if(simple_pattern_matches(t->pattern, name)) return -1;
+
+    return 0;
+}
+
+static int simple_pattern_match_name_and_value_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    struct simple_pattern_match_name_value *t = (struct simple_pattern_match_name_value *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    // we return -1 to stop the walkthrough on first match
+    if(simple_pattern_matches(t->pattern, name)) return -1;
+
+    size_t len = RRDLABELS_MAX_NAME_LENGTH + RRDLABELS_MAX_VALUE_LENGTH + 2; // +1 for =, +1 for \0
+    char tmp[len], *dst = &tmp[0];
+    const char *v = string2str(lb->label_value);
+
+    // copy the name
+    while(*name) *dst++ = *name++;
+
+    // add the equal
+    *dst++ = t->equal;
+
+    // add the value
+    while(*v) *dst++ = *v++;
+
+    // terminate it
+    *dst = '\0';
+
+    if(simple_pattern_matches(t->pattern, tmp)) return -1;
+
+    return 0;
+}
+
+bool rrdlabels_match_simple_pattern_parsed(DICTIONARY *labels, SIMPLE_PATTERN *pattern, char equal) {
+    if (!labels) return false;
+
+    struct simple_pattern_match_name_value t = {
+        .pattern = pattern,
+        .equal = equal
+    };
+
+    int ret = dictionary_walkthrough_read(labels, equal?simple_pattern_match_name_and_value_callback:simple_pattern_match_name_only_callback, &t);
+
+    return (ret == -1)?true:false;
+}
+
+bool rrdlabels_match_simple_pattern(DICTIONARY *labels, const char *simple_pattern_txt) {
+    if (!labels) return false;
+
+    SIMPLE_PATTERN *pattern = simple_pattern_create(simple_pattern_txt, " ,|\t\r\n\f\v", SIMPLE_PATTERN_EXACT);
+    char equal = '\0';
+
+    const char *s;
+    for(s = simple_pattern_txt; *s ; s++) {
+        if (*s == '=' || *s == ':') {
+            equal = *s;
+            break;
+        }
+    }
+
+    bool ret = rrdlabels_match_simple_pattern_parsed(labels, pattern, equal);
+
+    simple_pattern_free(pattern);
+
+    return ret;
+}
+
+
+// ----------------------------------------------------------------------------
+// Log all labels
+
+static int rrdlabels_log_label_to_buffer_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+
+    BUFFER *wb = (BUFFER *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    buffer_sprintf(wb, "Label: %s: \"%s\" (", name, string2str(lb->label_value));
+
+    size_t sources = 0;
+    if(lb->label_source & RRDLABEL_SRC_AUTO) {
+        buffer_sprintf(wb, "auto");
+        sources++;
+    }
+
+    if(lb->label_source & RRDLABEL_SRC_CONFIG)
+        buffer_sprintf(wb, "%snetdata.conf", sources++?",":"");
+
+    if(lb->label_source & RRDLABEL_SRC_K8S)
+        buffer_sprintf(wb, "%sk8s", sources++?",":"");
+
+    if(lb->label_source & RRDLABEL_SRC_ACLK)
+        buffer_sprintf(wb, "%saclk", sources++?",":"");
+
+    if(!sources)
+        buffer_strcat(wb, "unknown");
+
+    buffer_strcat(wb, ")\n");
+
+    return 1;
+}
+
+void rrdlabels_log_to_buffer(DICTIONARY *labels, BUFFER *wb) {
+    dictionary_sorted_walkthrough_read(labels, rrdlabels_log_label_to_buffer_callback, wb);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels_to_buffer()
+
+struct labels_to_buffer {
+    BUFFER *wb;
+    bool (*filter_callback)(const char *name, const char *value, RRDLABEL_SRC ls, void *data);
+    void *filter_data;
+    void (*name_sanitizer)(char *dst, const char *src, size_t dst_size);
+    void (*value_sanitizer)(char *dst, const char *src, size_t dst_size);
+    const char *before_each;
+    const char *quote;
+    const char *equal;
+    const char *between_them;
+    size_t count;
+};
+
+static int label_to_buffer_callback(const DICTIONARY_ITEM *item, void *value, void *data) {
+    const char *name = dictionary_acquired_item_name(item);
+    struct labels_to_buffer *t = (struct labels_to_buffer *)data;
+    RRDLABEL *lb = (RRDLABEL *)value;
+
+    size_t n_size = (t->name_sanitizer ) ? ( RRDLABELS_MAX_NAME_LENGTH  * 2 ) : 1;
+    size_t v_size = (t->value_sanitizer) ? ( RRDLABELS_MAX_VALUE_LENGTH * 2 ) : 1;
+
+    char n[n_size];
+    char v[v_size];
+
+    const char *nn = name, *vv = string2str(lb->label_value);
+
+    if(t->name_sanitizer) {
+        t->name_sanitizer(n, name, n_size);
+        nn = n;
+    }
+
+    if(t->value_sanitizer) {
+        t->value_sanitizer(v, string2str(lb->label_value), v_size);
+        vv = v;
+    }
+
+    if(!t->filter_callback || t->filter_callback(name, string2str(lb->label_value), lb->label_source, t->filter_data)) {
+        buffer_sprintf(t->wb, "%s%s%s%s%s%s%s%s%s", t->count++?t->between_them:"", t->before_each, t->quote, nn, t->quote, t->equal, t->quote, vv, t->quote);
+        return 1;
+    }
+
+    return 0;
+}
+
+int rrdlabels_to_buffer(DICTIONARY *labels, BUFFER *wb, const char *before_each, const char *equal, const char *quote, const char *between_them, bool (*filter_callback)(const char *name, const char *value, RRDLABEL_SRC ls, void *data), void *filter_data, void (*name_sanitizer)(char *dst, const char *src, size_t dst_size), void (*value_sanitizer)(char *dst, const char *src, size_t dst_size)) {
+    struct labels_to_buffer tmp = {
+        .wb = wb,
+        .filter_callback = filter_callback,
+        .filter_data = filter_data,
+        .name_sanitizer = name_sanitizer,
+        .value_sanitizer = value_sanitizer,
+        .before_each = before_each,
+        .equal = equal,
+        .quote = quote,
+        .between_them = between_them,
+        .count = 0
+    };
+    return dictionary_walkthrough_read(labels, label_to_buffer_callback, (void *)&tmp);
+}
+
+void rrdset_update_rrdlabels(RRDSET *st, DICTIONARY *new_rrdlabels) {
+    if(!st->rrdlabels)
+        st->rrdlabels = rrdlabels_create();
+
+    if (new_rrdlabels)
+        rrdlabels_migrate_to_these(st->rrdlabels, new_rrdlabels);
+
+    metaqueue_chart_labels(st);
+}
+
+
+// ----------------------------------------------------------------------------
+// rrdlabels unit test
+
+struct rrdlabels_unittest_add_a_pair {
+    const char *pair;
+    const char *expected_name;
+    const char *expected_value;
+    const char *name;
+    const char *value;
+    RRDLABEL_SRC ls;
+    int errors;
+};
+
+int rrdlabels_unittest_add_a_pair_callback(const char *name, const char *value, RRDLABEL_SRC ls, void *data) {
+    struct rrdlabels_unittest_add_a_pair *t = (struct rrdlabels_unittest_add_a_pair *)data;
+
+    t->name = name;
+    t->value = value;
+    t->ls = ls;
+
+    if(strcmp(name, t->expected_name) != 0) {
+        fprintf(stderr, "name is wrong, found \"%s\", expected \"%s\"", name, t->expected_name);
+        t->errors++;
+    }
+
+    if(value == NULL && t->expected_value == NULL) {
+        ;
+    }
+    else if(value == NULL || t->expected_value == NULL) {
+        fprintf(stderr, "value is wrong, found \"%s\", expected \"%s\"", value?value:"(null)", t->expected_value?t->expected_value:"(null)");
+        t->errors++;
+    }
+    else if(strcmp(value, t->expected_value) != 0) {
+        fprintf(stderr, "values don't match, found \"%s\", expected \"%s\"", value, t->expected_value);
+        t->errors++;
+    }
+
+    return 1;
+}
+
+int rrdlabels_unittest_add_a_pair(const char *pair, const char *name, const char *value) {
+    DICTIONARY *labels = rrdlabels_create();
+    int errors;
+
+    fprintf(stderr, "rrdlabels_add_pair(labels, %s) ... ", pair);
+
+    rrdlabels_add_pair(labels, pair, RRDLABEL_SRC_CONFIG);
+
+    struct rrdlabels_unittest_add_a_pair tmp = {
+        .pair = pair,
+        .expected_name = name,
+        .expected_value = value,
+        .errors = 0
+    };
+    int ret = rrdlabels_walkthrough_read(labels, rrdlabels_unittest_add_a_pair_callback, &tmp);
+    errors = tmp.errors;
+    if(ret != 1) {
+        fprintf(stderr, "failed to get \"%s\" label", name);
+        errors++;
+    }
+
+    if(!errors)
+        fprintf(stderr, " OK, name='%s' and value='%s'\n", tmp.name, tmp.value?tmp.value:"(null)");
+    else
+        fprintf(stderr, " FAILED\n");
+
+    rrdlabels_destroy(labels);
+    return errors;
+}
+
+int rrdlabels_unittest_add_pairs() {
+    fprintf(stderr, "\n%s() tests\n", __FUNCTION__);
+
+    int errors = 0;
+
+    // basic test
+    errors += rrdlabels_unittest_add_a_pair("tag=value", "tag", "value");
+    errors += rrdlabels_unittest_add_a_pair("tag:value", "tag", "value");
+
+    // test newlines
+    errors += rrdlabels_unittest_add_a_pair("   tag   = \t value \r\n", "tag", "value");
+
+    // test : in values
+    errors += rrdlabels_unittest_add_a_pair("tag=:value", "tag", ":value");
+    errors += rrdlabels_unittest_add_a_pair("tag::value", "tag", ":value");
+    errors += rrdlabels_unittest_add_a_pair("   tag   =   :value ", "tag", ":value");
+    errors += rrdlabels_unittest_add_a_pair("   tag   :   :value ", "tag", ":value");
+    errors += rrdlabels_unittest_add_a_pair("tag:5", "tag", "5");
+    errors += rrdlabels_unittest_add_a_pair("tag:55", "tag", "55");
+    errors += rrdlabels_unittest_add_a_pair("tag:aa", "tag", "aa");
+    errors += rrdlabels_unittest_add_a_pair("tag:a", "tag", "a");
+
+    // test empty values
+    errors += rrdlabels_unittest_add_a_pair("tag", "tag", "[none]");
+    errors += rrdlabels_unittest_add_a_pair("tag:", "tag", "[none]");
+    errors += rrdlabels_unittest_add_a_pair("tag:\"\"", "tag", "[none]");
+    errors += rrdlabels_unittest_add_a_pair("tag:''", "tag", "[none]");
+    errors += rrdlabels_unittest_add_a_pair("tag:\r\n", "tag", "[none]");
+    errors += rrdlabels_unittest_add_a_pair("tag\r\n", "tag", "[none]");
+
+    // test UTF-8 in values
+    errors += rrdlabels_unittest_add_a_pair("tag: country:Ελλάδα", "tag", "country:Ελλάδα");
+    errors += rrdlabels_unittest_add_a_pair("\"tag\": \"country:Ελλάδα\"", "tag", "country:Ελλάδα");
+    errors += rrdlabels_unittest_add_a_pair("\"tag\": country:\"Ελλάδα\"", "tag", "country:Ελλάδα");
+    errors += rrdlabels_unittest_add_a_pair("\"tag=1\": country:\"Gre\\\"ece\"", "tag_1", "country:Gre_ece");
+    errors += rrdlabels_unittest_add_a_pair("\"tag=1\" = country:\"Gre\\\"ece\"", "tag_1", "country:Gre_ece");
+
+    errors += rrdlabels_unittest_add_a_pair("\t'LABE=L'\t=\t\"World\" peace", "labe_l", "World peace");
+    errors += rrdlabels_unittest_add_a_pair("\t'LA\\'B:EL'\t=\tcountry:\"World\":\"Europe\":\"Greece\"", "la_b_el", "country:World:Europe:Greece");
+    errors += rrdlabels_unittest_add_a_pair("\t'LA\\'B:EL'\t=\tcountry\\\"World\"\\\"Europe\"\\\"Greece\"", "la_b_el", "country/World/Europe/Greece");
+
+    errors += rrdlabels_unittest_add_a_pair("NAME=\"VALUE\"", "name", "VALUE");
+    errors += rrdlabels_unittest_add_a_pair("\"NAME\" : \"VALUE\"", "name", "VALUE");
+    errors += rrdlabels_unittest_add_a_pair("NAME: \"VALUE\"", "name", "VALUE");
+
+    return errors;
+}
+
+int rrdlabels_unittest_check_simple_pattern(DICTIONARY *labels, const char *pattern, bool expected) {
+    fprintf(stderr, "rrdlabels_match_simple_pattern(labels, \"%s\") ... ", pattern);
+
+    bool ret = rrdlabels_match_simple_pattern(labels, pattern);
+    fprintf(stderr, "%s, got %s expected %s\n", (ret == expected)?"OK":"FAILED", ret?"true":"false", expected?"true":"false");
+
+    return (ret == expected)?0:1;
+}
+
+int rrdlabels_unittest_simple_pattern() {
+    fprintf(stderr, "\n%s() tests\n", __FUNCTION__);
+
+    int errors = 0;
+
+    DICTIONARY *labels = rrdlabels_create();
+    rrdlabels_add(labels, "tag1", "value1", RRDLABEL_SRC_CONFIG);
+    rrdlabels_add(labels, "tag2", "value2", RRDLABEL_SRC_CONFIG);
+    rrdlabels_add(labels, "tag3", "value3", RRDLABEL_SRC_CONFIG);
+
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag*", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*1", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "value*", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*=value*", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*:value*", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*2", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "*2 *3", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "!tag3 *2", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag1 tag2", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag1tag2", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "invalid1 invalid2 tag3", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "!tag1 tag4", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag1=value1", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag1=value2", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "tag*=value*", true);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "!tag*=value*", false);
+    errors += rrdlabels_unittest_check_simple_pattern(labels, "!tag2=something2 tag2=*2", true);
+
+    rrdlabels_destroy(labels);
+
+    return errors;
+}
+
+int rrdlabels_unittest_sanitize_value(const char *src, const char *expected) {
+    char buf[RRDLABELS_MAX_VALUE_LENGTH + 1];
+    size_t len = rrdlabels_sanitize_value(buf, src, RRDLABELS_MAX_VALUE_LENGTH);
+    size_t expected_len = strlen(expected);
+
+    int err = 0;
+    if(strcmp(buf, expected) != 0) err = 1;
+    if(len != expected_len) err = 1;
+
+    fprintf(stderr, "%s(%s): %s, expected '%s', got '%s', expected bytes = %zu, got bytes = %zu\n", __FUNCTION__, src, (err==1)?"FAILED":"OK", expected, buf, expected_len, strlen(buf));
+    return err;
+}
+
+int rrdlabels_unittest_sanitization() {
+    int errors = 0;
+
+    errors += rrdlabels_unittest_sanitize_value("", "[none]");
+    errors += rrdlabels_unittest_sanitize_value("1", "1");
+    errors += rrdlabels_unittest_sanitize_value("  hello   world   ", "hello world");
+
+    // 2-byte UTF-8
+    errors += rrdlabels_unittest_sanitize_value(" Ελλάδα ", "Ελλάδα");
+    errors += rrdlabels_unittest_sanitize_value("aŰbŲcŴ", "aŰbŲcŴ");
+    errors += rrdlabels_unittest_sanitize_value("Ű b Ų c Ŵ", "Ű b Ų c Ŵ");
+
+    // 3-byte UTF-8
+    errors += rrdlabels_unittest_sanitize_value("‱", "‱");
+    errors += rrdlabels_unittest_sanitize_value("a‱b", "a‱b");
+    errors += rrdlabels_unittest_sanitize_value("a ‱ b", "a ‱ b");
+
+    // 4-byte UTF-8
+    errors += rrdlabels_unittest_sanitize_value("𩸽", "𩸽");
+    errors += rrdlabels_unittest_sanitize_value("a𩸽b", "a𩸽b");
+    errors += rrdlabels_unittest_sanitize_value("a 𩸽 b", "a 𩸽 b");
+
+    // mixed multi-byte
+    errors += rrdlabels_unittest_sanitize_value("Ű‱𩸽‱Ű", "Ű‱𩸽‱Ű");
+
+    return errors;
+}
+
+int rrdlabels_unittest(void) {
+    int errors = 0;
+
+    errors += rrdlabels_unittest_sanitization();
+    errors += rrdlabels_unittest_add_pairs();
+    errors += rrdlabels_unittest_simple_pattern();
+
+    fprintf(stderr, "%d errors found\n", errors);
+    return errors;
+}