Merging upstream version 1.39.0.

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

3 files changed, 1096 insertions, 298 deletions

diff --git a/libnetdata/buffer/README.md b/libnetdata/buffer/README.md
index 6a84fd8a3..2937ae141 100644
--- a/libnetdata/buffer/README.md
+++ b/libnetdata/buffer/README.md
@@ -4,7 +4,7 @@ custom_edit_url: https://github.com/netdata/netdata/edit/master/libnetdata/buffe
 sidebar_label: "BUFFER library"
 learn_status: "Published"
 learn_topic_type: "Tasks"
-learn_rel_path: "Developers/libnetdata libraries"
+learn_rel_path: "Developers/libnetdata"
 -->
 
 # BUFFER
diff --git a/libnetdata/buffer/buffer.c b/libnetdata/buffer/buffer.c
index eeb283209..142fbca14 100644
--- a/libnetdata/buffer/buffer.c
+++ b/libnetdata/buffer/buffer.c
@@ -2,39 +2,16 @@
 
 #include "../libnetdata.h"
 
-#define BUFFER_OVERFLOW_EOF "EOF"
-
 static inline void buffer_overflow_init(BUFFER *b)
 {
     b->buffer[b->size] = '\0';
     strcpy(&b->buffer[b->size + 1], BUFFER_OVERFLOW_EOF);
 }
 
-#ifdef NETDATA_INTERNAL_CHECKS
-#define buffer_overflow_check(b) _buffer_overflow_check(b, __FILE__, __FUNCTION__, __LINE__)
-#else
-#define buffer_overflow_check(b)
-#endif
-
-static inline void _buffer_overflow_check(BUFFER *b, const char *file, const char *function, const unsigned long line)
-{
-    if(b->len > b->size) {
-        error("BUFFER: length %zu is above size %zu, at line %lu, at function %s() of file '%s'.", b->len, b->size, line, function, file);
-        b->len = b->size;
-    }
-
-    if(b->buffer[b->size] != '\0' || strcmp(&b->buffer[b->size + 1], BUFFER_OVERFLOW_EOF) != 0) {
-        error("BUFFER: detected overflow at line %lu, at function %s() of file '%s'.", line, function, file);
-        buffer_overflow_init(b);
-    }
-}
-
-
-void buffer_reset(BUFFER *wb)
-{
+void buffer_reset(BUFFER *wb) {
     buffer_flush(wb);
 
-    wb->contenttype = CT_TEXT_PLAIN;
+    wb->content_type = CT_TEXT_PLAIN;
     wb->options = 0;
     wb->date = 0;
     wb->expires = 0;
@@ -52,8 +29,7 @@ const char *buffer_tostring(BUFFER *wb)
     return(wb->buffer);
 }
 
-void buffer_char_replace(BUFFER *wb, char from, char to)
-{
+void buffer_char_replace(BUFFER *wb, char from, char to) {
     char *s = wb->buffer, *end = &wb->buffer[wb->len];
 
     while(s != end) {
@@ -64,212 +40,25 @@ void buffer_char_replace(BUFFER *wb, char from, char to)
     buffer_overflow_check(wb);
 }
 
-// This trick seems to give an 80% speed increase in 32bit systems
-// print_number_llu_r() will just print the digits up to the
-// point the remaining value fits in 32 bits, and then calls
-// print_number_lu_r() to print the rest with 32 bit arithmetic.
-
-inline char *print_number_lu_r(char *str, unsigned long uvalue) {
-    char *wstr = str;
-
-    // print each digit
-    do *wstr++ = (char)('0' + (uvalue % 10)); while(uvalue /= 10);
-    return wstr;
-}
-
-inline char *print_number_llu_r(char *str, unsigned long long uvalue) {
-    char *wstr = str;
-
-    // print each digit
-    do *wstr++ = (char)('0' + (uvalue % 10)); while((uvalue /= 10) && uvalue > (unsigned long long)0xffffffff);
-    if(uvalue) return print_number_lu_r(wstr, uvalue);
-    return wstr;
-}
-
-inline char *print_number_llu_r_smart(char *str, unsigned long long uvalue) {
-    switch (sizeof(void *)) {
-    case 4:
-        str = (uvalue > (unsigned long long) 0xffffffff) ? print_number_llu_r(str, uvalue) :
-                                                           print_number_lu_r(str, uvalue);
-        break;
-    case 8:
-        do {
-            *str++ = (char) ('0' + (uvalue % 10));
-        } while (uvalue /= 10);
-        break;
-    default:
-        fatal("Netdata supports only 32-bit & 64-bit systems.");
-    }
-
-    return str;
-}
-
-void buffer_print_llu(BUFFER *wb, unsigned long long uvalue)
-{
-    buffer_need_bytes(wb, 50);
-
-    char *str = &wb->buffer[wb->len];
-    char *wstr = str;
-
-    switch (sizeof(void *)) {
-    case 4:
-        wstr = (uvalue > (unsigned long long) 0xffffffff) ? print_number_llu_r(wstr, uvalue) :
-                                                            print_number_lu_r(wstr, uvalue);
-        break;
-    case 8:
-        do {
-            *wstr++ = (char) ('0' + (uvalue % 10));
-        } while (uvalue /= 10);
-        break;
-    default:
-        fatal("Netdata supports only 32-bit & 64-bit systems.");
+void buffer_print_sn_flags(BUFFER *wb, SN_FLAGS flags, bool send_anomaly_bit) {
+    if(unlikely(flags == SN_EMPTY_SLOT)) {
+        buffer_fast_strcat(wb, "E", 1);
+        return;
     }
 
-    // terminate it
-    *wstr = '\0';
-
-    // reverse it
-    char *begin = str, *end = wstr - 1, aux;
-    while (end > begin) aux = *end, *end-- = *begin, *begin++ = aux;
-
-    // return the buffer length
-    wb->len += wstr - str;
-}
-
-void buffer_print_ll(BUFFER *wb, long long value)
-{
-    buffer_need_bytes(wb, 50);
-
-    if(value < 0) {
-        buffer_fast_strcat(wb, "-", 1);
-        value = -value;
+    size_t printed = 0;
+    if(likely(send_anomaly_bit && (flags & SN_FLAG_NOT_ANOMALOUS))) {
+        buffer_fast_strcat(wb, "A", 1);
+        printed++;
     }
 
-    buffer_print_llu(wb, value);
-}
-
-static unsigned char bits03_to_hex[16] = {
-    [0] = '0',
-    [1] = '1',
-    [2] = '2',
-    [3] = '3',
-    [4] = '4',
-    [5] = '5',
-    [6] = '6',
-    [7] = '7',
-    [8] = '8',
-    [9] = '9',
-    [10] = 'A',
-    [11] = 'B',
-    [12] = 'C',
-    [13] = 'D',
-    [14] = 'E',
-    [15] = 'F'
-};
-
-void buffer_print_llu_hex(BUFFER *wb, unsigned long long value)
-{
-    unsigned char buffer[sizeof(unsigned long long) * 2 + 2 + 1];   // 8 bytes * 2 + '0x' + '\0'
-    unsigned char *e = &buffer[sizeof(unsigned long long) * 2 + 2];
-    unsigned char *p = e;
-
-    *p-- = '\0';
-    *p-- = bits03_to_hex[value & 0xF];
-    value >>= 4;
-    if(value) {
-        *p-- = bits03_to_hex[value & 0xF];
-        value >>= 4;
-
-        while(value) {
-            *p-- = bits03_to_hex[value & 0xF];
-            value >>= 4;
-
-            if(value) {
-                *p-- = bits03_to_hex[value & 0xF];
-                value >>= 4;
-            }
-        }
+    if(unlikely(flags & SN_FLAG_RESET)) {
+        buffer_fast_strcat(wb, "R", 1);
+        printed++;
     }
-    *p-- = 'x';
-    *p   = '0';
 
-    buffer_fast_strcat(wb, (char *)p, e - p);
-}
-
-void buffer_fast_strcat(BUFFER *wb, const char *txt, size_t len) {
-    if(unlikely(!txt || !*txt)) return;
-
-    buffer_need_bytes(wb, len + 1);
-
-    char *s = &wb->buffer[wb->len];
-    const char *end = &txt[len + 1];
-
-    while(txt != end)
-        *s++ = *txt++;
-
-    wb->len += len;
-
-    // keep it NULL terminating
-    // not counting it at wb->len
-    wb->buffer[wb->len] = '\0';
-}
-
-void buffer_strcat(BUFFER *wb, const char *txt)
-{
-    // buffer_sprintf(wb, "%s", txt);
-
-    if(unlikely(!txt || !*txt)) return;
-
-    buffer_need_bytes(wb, 1);
-
-    char *s = &wb->buffer[wb->len], *start, *end = &wb->buffer[wb->size];
-    size_t len = wb->len;
-
-    start = s;
-    while(*txt && s != end)
-        *s++ = *txt++;
-
-    len += s - start;
-
-    wb->len = len;
-    buffer_overflow_check(wb);
-
-    if(*txt) {
-        debug(D_WEB_BUFFER, "strcat(): increasing web_buffer at position %zu, size = %zu\n", wb->len, wb->size);
-        len = strlen(txt);
-        buffer_fast_strcat(wb, txt, len);
-    }
-    else {
-        // terminate the string
-        // without increasing the length
-        buffer_need_bytes(wb, (size_t)1);
-        wb->buffer[wb->len] = '\0';
-    }
-}
-
-void buffer_strcat_jsonescape(BUFFER *wb, const char *txt)
-{
-    while(*txt) {
-        switch(*txt) {
-            case '\\':
-                buffer_need_bytes(wb, 2);
-                wb->buffer[wb->len++] = '\\';
-                wb->buffer[wb->len++] = '\\';
-                break;
-            case '"':
-                buffer_need_bytes(wb, 2);
-                wb->buffer[wb->len++] = '\\';
-                wb->buffer[wb->len++] = '"';
-                break;
-            default: {
-                buffer_need_bytes(wb, 1);
-                wb->buffer[wb->len++] = *txt;
-            }
-        }
-        txt++;
-    }
-
-    buffer_overflow_check(wb);
+    if(!printed)
+        buffer_fast_strcat(wb, "''", 2);
 }
 
 void buffer_strcat_htmlescape(BUFFER *wb, const char *txt)
@@ -358,25 +147,6 @@ void buffer_sprintf(BUFFER *wb, const char *fmt, ...)
     // the buffer is \0 terminated by vsnprintf
 }
 
-
-void buffer_rrd_value(BUFFER *wb, NETDATA_DOUBLE value)
-{
-    buffer_need_bytes(wb, 50);
-
-    if(isnan(value) || isinf(value)) {
-        buffer_strcat(wb, "null");
-        return;
-    }
-    else
-        wb->len += print_netdata_double(&wb->buffer[wb->len], value);
-
-    // terminate it
-    buffer_need_bytes(wb, 1);
-    wb->buffer[wb->len] = '\0';
-
-    buffer_overflow_check(wb);
-}
-
 // generate a javascript date, the fastest possible way...
 void buffer_jsdate(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds)
 {
@@ -482,7 +252,7 @@ BUFFER *buffer_create(size_t size, size_t *statistics)
     b->buffer = mallocz(size + sizeof(BUFFER_OVERFLOW_EOF) + 2);
     b->buffer[0] = '\0';
     b->size = size;
-    b->contenttype = CT_TEXT_PLAIN;
+    b->content_type = CT_TEXT_PLAIN;
     b->statistics = statistics;
     buffer_overflow_init(b);
     buffer_overflow_check(b);
@@ -531,3 +301,205 @@ void buffer_increase(BUFFER *b, size_t free_size_required) {
     buffer_overflow_init(b);
     buffer_overflow_check(b);
 }
+
+// ----------------------------------------------------------------------------
+
+void buffer_json_initialize(BUFFER *wb, const char *key_quote, const char *value_quote, int depth,
+                       bool add_anonymous_object, bool minify) {
+    strncpyz(wb->json.key_quote, key_quote, BUFFER_QUOTE_MAX_SIZE);
+    strncpyz(wb->json.value_quote,  value_quote, BUFFER_QUOTE_MAX_SIZE);
+
+    wb->json.minify = minify;
+    wb->json.depth = (int8_t)(depth - 1);
+    _buffer_json_depth_push(wb, BUFFER_JSON_OBJECT);
+
+    if(add_anonymous_object)
+        buffer_fast_strcat(wb, "{", 1);
+}
+
+void buffer_json_finalize(BUFFER *wb) {
+    while(wb->json.depth >= 0) {
+        switch(wb->json.stack[wb->json.depth].type) {
+            case BUFFER_JSON_OBJECT:
+                buffer_json_object_close(wb);
+                break;
+
+            case BUFFER_JSON_ARRAY:
+                buffer_json_array_close(wb);
+                break;
+
+            default:
+                internal_fatal(true, "BUFFER: unknown json member type in stack");
+                break;
+        }
+    }
+
+    if(!wb->json.minify)
+        buffer_fast_strcat(wb, "\n", 1);
+}
+
+// ----------------------------------------------------------------------------
+
+const char hex_digits[16] = "0123456789ABCDEF";
+const char base64_digits[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+unsigned char hex_value_from_ascii[256];
+unsigned char base64_value_from_ascii[256];
+
+__attribute__((constructor)) void initialize_ascii_maps(void) {
+    for(size_t i = 0 ; i < 256 ; i++) {
+        hex_value_from_ascii[i] = 255;
+        base64_value_from_ascii[i] = 255;
+    }
+
+    for(size_t i = 0; i < 16 ; i++)
+        hex_value_from_ascii[(int)hex_digits[i]] = i;
+
+    for(size_t i = 0; i < 64 ; i++)
+        base64_value_from_ascii[(int)base64_digits[i]] = i;
+}
+
+// ----------------------------------------------------------------------------
+// unit test
+
+static int buffer_expect(BUFFER *wb, const char *expected) {
+    const char *generated = buffer_tostring(wb);
+
+    if(strcmp(generated, expected) != 0) {
+        error("BUFFER: mismatch.\nGenerated:\n%s\nExpected:\n%s\n",
+              generated, expected);
+        return 1;
+    }
+
+    return 0;
+}
+
+static int buffer_uint64_roundtrip(BUFFER *wb, NUMBER_ENCODING encoding, uint64_t value, const char *expected) {
+    int errors = 0;
+    buffer_flush(wb);
+    buffer_print_uint64_encoded(wb, encoding, value);
+
+    if(expected)
+        errors += buffer_expect(wb, expected);
+
+    uint64_t v = str2ull_encoded(buffer_tostring(wb));
+    if(v != value) {
+        error("BUFFER: string '%s' does resolves to %llu, expected %llu",
+              buffer_tostring(wb), (unsigned long long)v, (unsigned long long)value);
+        errors++;
+    }
+    buffer_flush(wb);
+    return errors;
+}
+
+static int buffer_int64_roundtrip(BUFFER *wb, NUMBER_ENCODING encoding, int64_t value, const char *expected) {
+    int errors = 0;
+    buffer_flush(wb);
+    buffer_print_int64_encoded(wb, encoding, value);
+
+    if(expected)
+        errors += buffer_expect(wb, expected);
+
+    int64_t v = str2ll_encoded(buffer_tostring(wb));
+    if(v != value) {
+        error("BUFFER: string '%s' does resolves to %lld, expected %lld",
+              buffer_tostring(wb), (long long)v, (long long)value);
+        errors++;
+    }
+    buffer_flush(wb);
+    return errors;
+}
+
+static int buffer_double_roundtrip(BUFFER *wb, NUMBER_ENCODING encoding, NETDATA_DOUBLE value, const char *expected) {
+    int errors = 0;
+    buffer_flush(wb);
+    buffer_print_netdata_double_encoded(wb, encoding, value);
+
+    if(expected)
+        errors += buffer_expect(wb, expected);
+
+    NETDATA_DOUBLE v = str2ndd_encoded(buffer_tostring(wb), NULL);
+    if(v != value) {
+        error("BUFFER: string '%s' does resolves to %.12f, expected %.12f",
+              buffer_tostring(wb), v, value);
+        errors++;
+    }
+    buffer_flush(wb);
+    return errors;
+}
+
+int buffer_unittest(void) {
+    int errors = 0;
+    BUFFER *wb = buffer_create(0, NULL);
+
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 0, "0");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_HEX, 0, "0x0");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_BASE64, 0, "#A");
+
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 1676071986, "1676071986");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_HEX, 1676071986, "0x63E6D432");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_BASE64, 1676071986, "#Bj5tQy");
+
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 18446744073709551615ULL, "18446744073709551615");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_HEX, 18446744073709551615ULL, "0xFFFFFFFFFFFFFFFF");
+    buffer_uint64_roundtrip(wb, NUMBER_ENCODING_BASE64, 18446744073709551615ULL, "#P//////////");
+
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 0, "0");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_HEX, 0, "0x0");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_BASE64, 0, "#A");
+
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, -1676071986, "-1676071986");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_HEX, -1676071986, "-0x63E6D432");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_BASE64, -1676071986, "-#Bj5tQy");
+
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_DECIMAL, (int64_t)-9223372036854775807ULL, "-9223372036854775807");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_HEX, (int64_t)-9223372036854775807ULL, "-0x7FFFFFFFFFFFFFFF");
+    buffer_int64_roundtrip(wb, NUMBER_ENCODING_BASE64, (int64_t)-9223372036854775807ULL, "-#H//////////");
+
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 0, "0");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_HEX, 0, "%0");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_BASE64, 0, "@A");
+
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 1.5, "1.5");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_HEX, 1.5, "%3FF8000000000000");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_BASE64, 1.5, "@D/4AAAAAAAA");
+
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 1.23e+14, "123000000000000");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_HEX, 1.23e+14, "%42DBF78AD3AC0000");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_BASE64, 1.23e+14, "@ELb94rTrAAA");
+
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_DECIMAL, 9.12345678901234567890123456789e+45, "9.123456789012346128e+45");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_HEX, 9.12345678901234567890123456789e+45, "%497991C25C9E4309");
+    buffer_double_roundtrip(wb, NUMBER_ENCODING_BASE64, 9.12345678901234567890123456789e+45, "@El5kcJcnkMJ");
+
+    buffer_flush(wb);
+
+    {
+        char buf[1024 + 1];
+        for(size_t i = 0; i < 1024 ;i++)
+            buf[i] = (char)(i % 26) + 'A';
+        buf[1024] = '\0';
+
+        buffer_strcat(wb, buf);
+        errors += buffer_expect(wb, buf);
+    }
+
+    buffer_flush(wb);
+
+    buffer_json_initialize(wb, "\"", "\"", 0, true, false);
+    buffer_json_finalize(wb);
+    errors += buffer_expect(wb, "{\n}\n");
+
+    buffer_flush(wb);
+
+    buffer_json_initialize(wb, "\"", "\"", 0, true, false);
+    buffer_json_member_add_string(wb, "hello", "world");
+    buffer_json_member_add_string(wb, "alpha", "this: \" is a double quote");
+    buffer_json_member_add_object(wb, "object1");
+    buffer_json_member_add_string(wb, "hello", "world");
+    buffer_json_finalize(wb);
+    errors += buffer_expect(wb, "{\n    \"hello\":\"world\",\n    \"alpha\":\"this: \\\" is a double quote\",\n    \"object1\":{\n        \"hello\":\"world\"\n    }\n}\n");
+
+    buffer_free(wb);
+    return errors;
+}
+
diff --git a/libnetdata/buffer/buffer.h b/libnetdata/buffer/buffer.h
index 0fa3495b4..f5f83bc2a 100644
--- a/libnetdata/buffer/buffer.h
+++ b/libnetdata/buffer/buffer.h
@@ -3,48 +3,80 @@
 #ifndef NETDATA_WEB_BUFFER_H
 #define NETDATA_WEB_BUFFER_H 1
 
+#include "../string/utf8.h"
 #include "../libnetdata.h"
 
 #define WEB_DATA_LENGTH_INCREASE_STEP 1024
 
+#define BUFFER_JSON_MAX_DEPTH 32 // max is 255
+
+extern const char hex_digits[16];
+extern const char base64_digits[64];
+extern unsigned char hex_value_from_ascii[256];
+extern unsigned char base64_value_from_ascii[256];
+
+typedef enum __attribute__ ((__packed__)) {
+    BUFFER_JSON_EMPTY = 0,
+    BUFFER_JSON_OBJECT,
+    BUFFER_JSON_ARRAY,
+} BUFFER_JSON_NODE_TYPE;
+
+typedef struct web_buffer_json_node {
+    BUFFER_JSON_NODE_TYPE type;
+    uint32_t count:24;
+} BUFFER_JSON_NODE;
+
+#define BUFFER_QUOTE_MAX_SIZE 7
+
+typedef enum __attribute__ ((__packed__)) {
+    WB_CONTENT_CACHEABLE = (1 << 0),
+    WB_CONTENT_NO_CACHEABLE = (1 << 1),
+} BUFFER_OPTIONS;
+
+typedef enum __attribute__ ((__packed__)) {
+    CT_NONE = 0,
+    CT_APPLICATION_JSON,
+    CT_TEXT_PLAIN,
+    CT_TEXT_HTML,
+    CT_APPLICATION_X_JAVASCRIPT,
+    CT_TEXT_CSS,
+    CT_TEXT_XML,
+    CT_APPLICATION_XML,
+    CT_TEXT_XSL,
+    CT_APPLICATION_OCTET_STREAM,
+    CT_APPLICATION_X_FONT_TRUETYPE,
+    CT_APPLICATION_X_FONT_OPENTYPE,
+    CT_APPLICATION_FONT_WOFF,
+    CT_APPLICATION_FONT_WOFF2,
+    CT_APPLICATION_VND_MS_FONTOBJ,
+    CT_IMAGE_SVG_XML,
+    CT_IMAGE_PNG,
+    CT_IMAGE_JPG,
+    CT_IMAGE_GIF,
+    CT_IMAGE_XICON,
+    CT_IMAGE_ICNS,
+    CT_IMAGE_BMP,
+    CT_PROMETHEUS,
+} HTTP_CONTENT_TYPE;
+
 typedef struct web_buffer {
-    size_t size;        	// allocation size of buffer, in bytes
-    size_t len;     		// current data length in buffer, in bytes
-    char *buffer;   		// the buffer itself
-    uint8_t contenttype;	// the content type of the data in the buffer
-    uint8_t options;		// options related to the content
-    time_t date;    		// the timestamp this content has been generated
-    time_t expires;			// the timestamp this content expires
+    size_t size;            // allocation size of buffer, in bytes
+    size_t len;             // current data length in buffer, in bytes
+    char *buffer;           // the buffer itself
+    HTTP_CONTENT_TYPE content_type;    // the content type of the data in the buffer
+    BUFFER_OPTIONS options; // options related to the content
+    time_t date;            // the timestamp this content has been generated
+    time_t expires;         // the timestamp this content expires
     size_t *statistics;
-} BUFFER;
 
-// options
-#define WB_CONTENT_CACHEABLE            1
-#define WB_CONTENT_NO_CACHEABLE         2
-
-// content-types
-#define CT_APPLICATION_JSON             1
-#define CT_TEXT_PLAIN                   2
-#define CT_TEXT_HTML                    3
-#define CT_APPLICATION_X_JAVASCRIPT     4
-#define CT_TEXT_CSS                     5
-#define CT_TEXT_XML                     6
-#define CT_APPLICATION_XML              7
-#define CT_TEXT_XSL                     8
-#define CT_APPLICATION_OCTET_STREAM     9
-#define CT_APPLICATION_X_FONT_TRUETYPE  10
-#define CT_APPLICATION_X_FONT_OPENTYPE  11
-#define CT_APPLICATION_FONT_WOFF        12
-#define CT_APPLICATION_FONT_WOFF2       13
-#define CT_APPLICATION_VND_MS_FONTOBJ   14
-#define CT_IMAGE_SVG_XML                15
-#define CT_IMAGE_PNG                    16
-#define CT_IMAGE_JPG                    17
-#define CT_IMAGE_GIF                    18
-#define CT_IMAGE_XICON                  19
-#define CT_IMAGE_ICNS                   20
-#define CT_IMAGE_BMP                    21
-#define CT_PROMETHEUS                   22
+    struct {
+        char key_quote[BUFFER_QUOTE_MAX_SIZE + 1];
+        char value_quote[BUFFER_QUOTE_MAX_SIZE + 1];
+        int8_t depth;
+        bool minify;
+        BUFFER_JSON_NODE stack[BUFFER_JSON_MAX_DEPTH];
+    } json;
+} BUFFER;
 
 #define buffer_cacheable(wb)    do { (wb)->options |= WB_CONTENT_CACHEABLE;    if((wb)->options & WB_CONTENT_NO_CACHEABLE) (wb)->options &= ~WB_CONTENT_NO_CACHEABLE; } while(0)
 #define buffer_no_cacheable(wb) do { (wb)->options |= WB_CONTENT_NO_CACHEABLE; if((wb)->options & WB_CONTENT_CACHEABLE)    (wb)->options &= ~WB_CONTENT_CACHEABLE;  (wb)->expires = 0; } while(0)
@@ -52,12 +84,34 @@ typedef struct web_buffer {
 #define buffer_strlen(wb) ((wb)->len)
 const char *buffer_tostring(BUFFER *wb);
 
-#define buffer_flush(wb) wb->buffer[(wb)->len = 0] = '\0'
-void buffer_reset(BUFFER *wb);
+#define BUFFER_OVERFLOW_EOF "EOF"
+
+#ifdef NETDATA_INTERNAL_CHECKS
+#define buffer_overflow_check(b) _buffer_overflow_check(b)
+#else
+#define buffer_overflow_check(b)
+#endif
+
+static inline void _buffer_overflow_check(BUFFER *b) {
+    assert(b->len <= b->size &&
+                   "BUFFER: length is above buffer size.");
+
+    assert(!(b->buffer && (b->buffer[b->size] != '\0' || strcmp(&b->buffer[b->size + 1], BUFFER_OVERFLOW_EOF) != 0)) &&
+                   "BUFFER: detected overflow.");
+}
+
+static inline void buffer_flush(BUFFER *wb) {
+    wb->len = 0;
 
-void buffer_strcat(BUFFER *wb, const char *txt);
-void buffer_fast_strcat(BUFFER *wb, const char *txt, size_t len);
-void buffer_rrd_value(BUFFER *wb, NETDATA_DOUBLE value);
+    wb->json.depth = 0;
+    wb->json.stack[0].type = BUFFER_JSON_EMPTY;
+    wb->json.stack[0].count = 0;
+
+    if(wb->buffer)
+        wb->buffer[0] = '\0';
+}
+
+void buffer_reset(BUFFER *wb);
 
 void buffer_date(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds);
 void buffer_jsdate(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds);
@@ -69,22 +123,794 @@ void buffer_increase(BUFFER *b, size_t free_size_required);
 void buffer_snprintf(BUFFER *wb, size_t len, const char *fmt, ...) PRINTFLIKE(3, 4);
 void buffer_vsprintf(BUFFER *wb, const char *fmt, va_list args);
 void buffer_sprintf(BUFFER *wb, const char *fmt, ...) PRINTFLIKE(2,3);
-void buffer_strcat_jsonescape(BUFFER *wb, const char *txt);
 void buffer_strcat_htmlescape(BUFFER *wb, const char *txt);
 
 void buffer_char_replace(BUFFER *wb, char from, char to);
 
-char *print_number_lu_r(char *str, unsigned long uvalue);
-char *print_number_llu_r(char *str, unsigned long long uvalue);
-char *print_number_llu_r_smart(char *str, unsigned long long uvalue);
-
-void buffer_print_llu(BUFFER *wb, unsigned long long uvalue);
-void buffer_print_ll(BUFFER *wb, long long value);
-void buffer_print_llu_hex(BUFFER *wb, unsigned long long value);
+void buffer_print_sn_flags(BUFFER *wb, SN_FLAGS flags, bool send_anomaly_bit);
 
 static inline void buffer_need_bytes(BUFFER *buffer, size_t needed_free_size) {
-    if(unlikely(buffer->size - buffer->len < needed_free_size))
-        buffer_increase(buffer, needed_free_size);
+    if(unlikely(buffer->len + needed_free_size >= buffer->size))
+        buffer_increase(buffer, needed_free_size + 1);
+}
+
+void buffer_json_initialize(BUFFER *wb, const char *key_quote, const char *value_quote, int depth,
+                            bool add_anonymous_object, bool minify);
+
+void buffer_json_finalize(BUFFER *wb);
+
+static inline void _buffer_json_depth_push(BUFFER *wb, BUFFER_JSON_NODE_TYPE type) {
+#ifdef NETDATA_INTERNAL_CHECKS
+    assert(wb->json.depth <= BUFFER_JSON_MAX_DEPTH && "BUFFER JSON: max nesting reached");
+#endif
+    wb->json.depth++;
+    wb->json.stack[wb->json.depth].count = 0;
+    wb->json.stack[wb->json.depth].type = type;
+}
+
+static inline void _buffer_json_depth_pop(BUFFER *wb) {
+    wb->json.depth--;
+}
+
+static inline void buffer_fast_charcat(BUFFER *wb, const char c) {
+
+    buffer_need_bytes(wb, 2);
+    *(&wb->buffer[wb->len]) = c;
+    wb->len += 1;
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_fast_rawcat(BUFFER *wb, const char *txt, size_t len) {
+    if(unlikely(!txt || !*txt || !len)) return;
+
+    buffer_need_bytes(wb, len + 1);
+
+    const char *t = txt;
+    const char *e = &txt[len];
+
+    char *d = &wb->buffer[wb->len];
+
+    while(t != e)
+        *d++ = *t++;
+
+    wb->len += len;
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_fast_strcat(BUFFER *wb, const char *txt, size_t len) {
+    if(unlikely(!txt || !*txt || !len)) return;
+
+    buffer_need_bytes(wb, len + 1);
+
+    const char *t = txt;
+    const char *e = &txt[len];
+
+    char *d = &wb->buffer[wb->len];
+
+    while(t != e
+#ifdef NETDATA_INTERNAL_CHECKS
+          && *t
+#endif
+            )
+        *d++ = *t++;
+
+#ifdef NETDATA_INTERNAL_CHECKS
+    assert(!(t != e && !*t) && "BUFFER: source string is shorter than the length given.");
+#endif
+
+    wb->len += len;
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_strcat(BUFFER *wb, const char *txt) {
+    if(unlikely(!txt || !*txt)) return;
+
+    const char *t = txt;
+    while(*t) {
+        buffer_need_bytes(wb, 100);
+        char *s = &wb->buffer[wb->len];
+        char *d = s;
+        const char *e = &wb->buffer[wb->size];
+
+        while(*t && d < e)
+            *d++ = *t++;
+
+        wb->len += d - s;
+    }
+
+    buffer_need_bytes(wb, 1);
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_strncat(BUFFER *wb, const char *txt, size_t len) {
+    if(unlikely(!txt || !*txt)) return;
+
+    const char *t = txt;
+    while(*t) {
+        buffer_need_bytes(wb, len);
+        char *s = &wb->buffer[wb->len];
+        char *d = s;
+        const char *e = &wb->buffer[wb->len + len];
+
+        while(*t && d < e)
+            *d++ = *t++;
+
+        wb->len += d - s;
+    }
+
+    buffer_need_bytes(wb, 1);
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_json_strcat(BUFFER *wb, const char *txt) {
+    if(unlikely(!txt || !*txt)) return;
+
+    const unsigned char *t = (const unsigned char *)txt;
+    while(*t) {
+        buffer_need_bytes(wb, 110);
+        unsigned char *s = (unsigned char *)&wb->buffer[wb->len];
+        unsigned char *d = s;
+        const unsigned char *e = (unsigned char *)&wb->buffer[wb->size - 10]; // make room for the max escape sequence
+
+        while(*t && d < e) {
+#ifdef BUFFER_JSON_ESCAPE_UTF
+            if(unlikely(IS_UTF8_STARTBYTE(*t) && IS_UTF8_BYTE(t[1]))) {
+                // 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 && t[utf_character_size] && IS_UTF8_BYTE(t[utf_character_size]) && !IS_UTF8_STARTBYTE(t[utf_character_size]))
+                    utf_character_size++;
+
+                uint32_t code_point = 0;
+                for (size_t i = 0; i < utf_character_size; i++) {
+                    code_point <<= 6;
+                    code_point |= (t[i] & 0x3F);
+                }
+
+                t += utf_character_size;
+
+                // encode as \u escape sequence
+                *d++ = '\\';
+                *d++ = 'u';
+                *d++ = hex_digits[(code_point >> 12) & 0xf];
+                *d++ = hex_digits[(code_point >> 8) & 0xf];
+                *d++ = hex_digits[(code_point >> 4) & 0xf];
+                *d++ = hex_digits[code_point & 0xf];
+            }
+            else
+#endif
+            if(unlikely(*t < ' ')) {
+                uint32_t v = *t++;
+                *d++ = '\\';
+                *d++ = 'u';
+                *d++ = hex_digits[(v >> 12) & 0xf];
+                *d++ = hex_digits[(v >> 8) & 0xf];
+                *d++ = hex_digits[(v >> 4) & 0xf];
+                *d++ = hex_digits[v & 0xf];
+            }
+            else {
+                if (unlikely(*t == '\\' || *t == '\"'))
+                    *d++ = '\\';
+
+                *d++ = *t++;
+            }
+        }
+
+        wb->len += d - s;
+    }
+
+    buffer_need_bytes(wb, 1);
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_json_quoted_strcat(BUFFER *wb, const char *txt) {
+    if(unlikely(!txt || !*txt)) return;
+
+    if(*txt == '"')
+        txt++;
+
+    const char *t = txt;
+    while(*t) {
+        buffer_need_bytes(wb, 100);
+        char *s = &wb->buffer[wb->len];
+        char *d = s;
+        const char *e = &wb->buffer[wb->size - 1]; // remove 1 to make room for the escape character
+
+        while(*t && d < e) {
+            if(unlikely(*t == '"' && !t[1])) {
+                t++;
+                continue;
+            }
+
+            if(unlikely(*t == '\\' || *t == '"'))
+                *d++ = '\\';
+
+            *d++ = *t++;
+        }
+
+        wb->len += d - s;
+    }
+
+    buffer_need_bytes(wb, 1);
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+// This trick seems to give an 80% speed increase in 32bit systems
+// print_number_llu_r() will just print the digits up to the
+// point the remaining value fits in 32 bits, and then calls
+// print_number_lu_r() to print the rest with 32 bit arithmetic.
+
+static inline char *print_uint32_reversed(char *dst, uint32_t value) {
+    char *d = dst;
+    do *d++ = (char)('0' + (value % 10)); while((value /= 10));
+    return d;
+}
+
+static inline char *print_uint64_reversed(char *dst, uint64_t value) {
+#ifdef ENV32BIT
+    if(value <= (uint64_t)0xffffffff)
+        return print_uint32_reversed(dst, value);
+
+    char *d = dst;
+    do *d++ = (char)('0' + (value % 10)); while((value /= 10) && value > (uint64_t)0xffffffff);
+    if(value) return print_uint32_reversed(d, value);
+    return d;
+#else
+    char *d = dst;
+    do *d++ = (char)('0' + (value % 10)); while((value /= 10));
+    return d;
+#endif
+}
+
+static inline char *print_uint32_hex_reversed(char *dst, uint32_t value) {
+    static const char *digits = "0123456789ABCDEF";
+    char *d = dst;
+    do *d++ = digits[value & 0xf]; while((value >>= 4));
+    return d;
+}
+
+static inline char *print_uint64_hex_reversed(char *dst, uint64_t value) {
+#ifdef ENV32BIT
+    if(value <= (uint64_t)0xffffffff)
+        return print_uint32_hex_reversed(dst, value);
+
+    char *d = dst;
+    do *d++ = hex_digits[value & 0xf]; while((value >>= 4) && value > (uint64_t)0xffffffff);
+    if(value) return print_uint32_hex_reversed(d, value);
+    return d;
+#else
+    char *d = dst;
+    do *d++ = hex_digits[value & 0xf]; while((value >>= 4));
+    return d;
+#endif
+}
+
+static inline char *print_uint64_base64_reversed(char *dst, uint64_t value) {
+    char *d = dst;
+    do *d++ = base64_digits[value & 63]; while ((value >>= 6));
+    return d;
+}
+
+static inline void char_array_reverse(char *from, char *to) {
+    // from and to are inclusive
+    char *begin = from, *end = to, aux;
+    while (end > begin) aux = *end, *end-- = *begin, *begin++ = aux;
+}
+
+static inline int print_netdata_double(char *dst, NETDATA_DOUBLE value) {
+    char *s = dst;
+
+    if(unlikely(value < 0)) {
+        *s++ = '-';
+        value = fabsndd(value);
+    }
+
+    uint64_t fractional_precision = 10000000ULL; // fractional part 7 digits
+    int fractional_wanted_digits = 7;
+    int exponent = 0;
+    if(unlikely(value >= (NETDATA_DOUBLE)(UINT64_MAX / 10))) {
+        // the number is too big to print using 64bit numbers
+        // so, let's convert it to exponential notation
+        exponent = (int)(floorndd(log10ndd(value)));
+        value /= powndd(10, exponent);
+
+        // the max precision we can support is 18 digits
+        // (UINT64_MAX is 20, but the first is 1)
+        fractional_precision = 1000000000000000000ULL; // fractional part 18 digits
+        fractional_wanted_digits = 18;
+    }
+
+    char *d = s;
+    NETDATA_DOUBLE integral_d, fractional_d;
+    fractional_d = modfndd(value, &integral_d);
+
+    // get the integral and the fractional parts as 64-bit integers
+    uint64_t integral = (uint64_t)integral_d;
+    uint64_t fractional = (uint64_t)llrintndd(fractional_d * (NETDATA_DOUBLE)fractional_precision);
+    if(unlikely(fractional >= fractional_precision)) {
+        integral++;
+        fractional -= fractional_precision;
+    }
+
+    // convert the integral part to string (reversed)
+    d = print_uint64_reversed(d, integral);
+    char_array_reverse(s, d - 1);      // copy reversed the integral string
+
+    if(likely(fractional != 0)) {
+        *d++ = '.'; // add the dot
+
+        // convert the fractional part to string (reversed)
+        d = print_uint64_reversed(s = d, fractional);
+
+        while(d - s < fractional_wanted_digits) *d++ = '0'; // prepend zeros to reach precision
+        char_array_reverse(s, d - 1);   // copy reversed the fractional string
+
+        // remove trailing zeros from the fractional part
+        while(*(d - 1) == '0') d--;
+    }
+
+    if(unlikely(exponent != 0)) {
+        *d++ = 'e';
+        *d++ = '+';
+        d = print_uint32_reversed(s = d, exponent);
+        char_array_reverse(s, d - 1);
+    }
+
+    *d = '\0';
+    return (int)(d - dst);
+}
+
+static inline void buffer_print_uint64(BUFFER *wb, uint64_t value) {
+    buffer_need_bytes(wb, 50);
+
+    char *s = &wb->buffer[wb->len];
+    char *d = print_uint64_reversed(s, value);
+    char_array_reverse(s, d - 1);
+    *d = '\0';
+    wb->len += d - s;
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_int64(BUFFER *wb, int64_t value) {
+    buffer_need_bytes(wb, 50);
+
+    if(value < 0) {
+        buffer_fast_strcat(wb, "-", 1);
+        value = -value;
+    }
+
+    buffer_print_uint64(wb, (uint64_t)value);
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_uint64_hex(BUFFER *wb, uint64_t value) {
+    buffer_need_bytes(wb, sizeof(uint64_t) * 2 + 2 + 1);
+
+    buffer_fast_strcat(wb, HEX_PREFIX, sizeof(HEX_PREFIX) - 1);
+
+    char *s = &wb->buffer[wb->len];
+    char *d = print_uint64_hex_reversed(s, value);
+    char_array_reverse(s, d - 1);
+    *d = '\0';
+    wb->len += d - s;
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_uint64_base64(BUFFER *wb, uint64_t value) {
+    buffer_need_bytes(wb, sizeof(uint64_t) * 2 + 2 + 1);
+
+    buffer_fast_strcat(wb, IEEE754_UINT64_B64_PREFIX, sizeof(IEEE754_UINT64_B64_PREFIX) - 1);
+
+    char *s = &wb->buffer[wb->len];
+    char *d = print_uint64_base64_reversed(s, value);
+    char_array_reverse(s, d - 1);
+    *d = '\0';
+    wb->len += d - s;
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_int64_hex(BUFFER *wb, int64_t value) {
+    buffer_need_bytes(wb, 2);
+
+    if(value < 0) {
+        buffer_fast_strcat(wb, "-", 1);
+        value = -value;
+    }
+
+    buffer_print_uint64_hex(wb, (uint64_t)value);
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_int64_base64(BUFFER *wb, int64_t value) {
+    buffer_need_bytes(wb, 2);
+
+    if(value < 0) {
+        buffer_fast_strcat(wb, "-", 1);
+        value = -value;
+    }
+
+    buffer_print_uint64_base64(wb, (uint64_t)value);
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_netdata_double(BUFFER *wb, NETDATA_DOUBLE value) {
+    buffer_need_bytes(wb, 512 + 2);
+
+    if(isnan(value) || isinf(value)) {
+        buffer_fast_strcat(wb, "null", 4);
+        return;
+    }
+    else
+        wb->len += print_netdata_double(&wb->buffer[wb->len], value);
+
+    // terminate it
+    buffer_need_bytes(wb, 1);
+    wb->buffer[wb->len] = '\0';
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_netdata_double_hex(BUFFER *wb, NETDATA_DOUBLE value) {
+    buffer_need_bytes(wb, sizeof(uint64_t) * 2 + 2 + 1 + 1);
+
+    uint64_t *ptr = (uint64_t *) (&value);
+    buffer_fast_strcat(wb, IEEE754_DOUBLE_HEX_PREFIX, sizeof(IEEE754_DOUBLE_HEX_PREFIX) - 1);
+
+    char *s = &wb->buffer[wb->len];
+    char *d = print_uint64_hex_reversed(s, *ptr);
+    char_array_reverse(s, d - 1);
+    *d = '\0';
+    wb->len += d - s;
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_netdata_double_base64(BUFFER *wb, NETDATA_DOUBLE value) {
+    buffer_need_bytes(wb, sizeof(uint64_t) * 2 + 2 + 1 + 1);
+
+    uint64_t *ptr = (uint64_t *) (&value);
+    buffer_fast_strcat(wb, IEEE754_DOUBLE_B64_PREFIX, sizeof(IEEE754_DOUBLE_B64_PREFIX) - 1);
+
+    char *s = &wb->buffer[wb->len];
+    char *d = print_uint64_base64_reversed(s, *ptr);
+    char_array_reverse(s, d - 1);
+    *d = '\0';
+    wb->len += d - s;
+
+    buffer_overflow_check(wb);
+}
+
+typedef enum {
+    NUMBER_ENCODING_DECIMAL,
+    NUMBER_ENCODING_HEX,
+    NUMBER_ENCODING_BASE64,
+} NUMBER_ENCODING;
+
+static inline void buffer_print_int64_encoded(BUFFER *wb, NUMBER_ENCODING encoding, int64_t value) {
+    if(encoding == NUMBER_ENCODING_BASE64)
+        return buffer_print_int64_base64(wb, value);
+
+    if(encoding == NUMBER_ENCODING_HEX)
+        return buffer_print_int64_hex(wb, value);
+
+    return buffer_print_int64(wb, value);
+}
+
+static inline void buffer_print_uint64_encoded(BUFFER *wb, NUMBER_ENCODING encoding, uint64_t value) {
+    if(encoding == NUMBER_ENCODING_BASE64)
+        return buffer_print_uint64_base64(wb, value);
+
+    if(encoding == NUMBER_ENCODING_HEX)
+        return buffer_print_uint64_hex(wb, value);
+
+    return buffer_print_uint64(wb, value);
+}
+
+static inline void buffer_print_netdata_double_encoded(BUFFER *wb, NUMBER_ENCODING encoding, NETDATA_DOUBLE value) {
+    if(encoding == NUMBER_ENCODING_BASE64)
+        return buffer_print_netdata_double_base64(wb, value);
+
+    if(encoding == NUMBER_ENCODING_HEX)
+        return buffer_print_netdata_double_hex(wb, value);
+
+    return buffer_print_netdata_double(wb, value);
+}
+
+static inline void buffer_print_spaces(BUFFER *wb, size_t spaces) {
+    buffer_need_bytes(wb, spaces * 4 + 1);
+
+    char *d = &wb->buffer[wb->len];
+    for(size_t i = 0; i < spaces; i++) {
+        *d++ = ' ';
+        *d++ = ' ';
+        *d++ = ' ';
+        *d++ = ' ';
+    }
+
+    *d = '\0';
+    wb->len += spaces * 4;
+
+    buffer_overflow_check(wb);
+}
+
+static inline void buffer_print_json_comma_newline_spacing(BUFFER *wb) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    if(wb->json.minify)
+        return;
+
+    buffer_fast_strcat(wb, "\n", 1);
+    buffer_print_spaces(wb, wb->json.depth + 1);
+}
+
+static inline void buffer_print_json_key(BUFFER *wb, const char *key) {
+    buffer_strcat(wb, wb->json.key_quote);
+    buffer_json_strcat(wb, key);
+    buffer_strcat(wb, wb->json.key_quote);
+}
+
+static inline void buffer_json_add_string_value(BUFFER *wb, const char *value) {
+    if(value) {
+        buffer_strcat(wb, wb->json.value_quote);
+        buffer_json_strcat(wb, value);
+        buffer_strcat(wb, wb->json.value_quote);
+    }
+    else
+        buffer_fast_strcat(wb, "null", 4);
+}
+
+static inline void buffer_json_add_quoted_string_value(BUFFER *wb, const char *value) {
+    if(value) {
+        buffer_strcat(wb, wb->json.value_quote);
+        buffer_json_quoted_strcat(wb, value);
+        buffer_strcat(wb, wb->json.value_quote);
+    }
+    else
+        buffer_fast_strcat(wb, "null", 4);
+}
+
+static inline void buffer_json_member_add_object(BUFFER *wb, const char *key) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":{", 2);
+    wb->json.stack[wb->json.depth].count++;
+
+    _buffer_json_depth_push(wb, BUFFER_JSON_OBJECT);
+}
+
+static inline void buffer_json_object_close(BUFFER *wb) {
+#ifdef NETDATA_INTERNAL_CHECKS
+    assert(wb->json.depth >= 0 && "BUFFER JSON: nothing is open to close it");
+    assert(wb->json.stack[wb->json.depth].type == BUFFER_JSON_OBJECT && "BUFFER JSON: an object is not open to close it");
+#endif
+    if(!wb->json.minify) {
+        buffer_fast_strcat(wb, "\n", 1);
+        buffer_print_spaces(wb, wb->json.depth);
+    }
+    buffer_fast_strcat(wb, "}", 1);
+    _buffer_json_depth_pop(wb);
+}
+
+static inline void buffer_json_member_add_string(BUFFER *wb, const char *key, const char *value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_json_add_string_value(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_string_or_omit(BUFFER *wb, const char *key, const char *value) {
+    if(value && *value)
+        buffer_json_member_add_string(wb, key, value);
+}
+
+static inline void buffer_json_member_add_string_or_empty(BUFFER *wb, const char *key, const char *value) {
+    if(!value)
+        value = "";
+
+    buffer_json_member_add_string(wb, key, value);
+}
+
+static inline void buffer_json_member_add_quoted_string(BUFFER *wb, const char *key, const char *value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+
+    if(!value || strcmp(value, "null") == 0)
+        buffer_fast_strcat(wb, "null", 4);
+    else
+        buffer_json_add_quoted_string_value(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_uuid(BUFFER *wb, const char *key, uuid_t *value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+
+    if(value) {
+        char uuid[GUID_LEN + 1];
+        uuid_unparse_lower(*value, uuid);
+        buffer_json_add_string_value(wb, uuid);
+    }
+    else
+        buffer_json_add_string_value(wb, NULL);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_boolean(BUFFER *wb, const char *key, bool value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_strcat(wb, value?"true":"false");
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_array(BUFFER *wb, const char *key) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":[", 2);
+    wb->json.stack[wb->json.depth].count++;
+
+    _buffer_json_depth_push(wb, BUFFER_JSON_ARRAY);
+}
+
+static inline void buffer_json_add_array_item_array(BUFFER *wb) {
+    buffer_print_json_comma_newline_spacing(wb);
+
+    buffer_fast_strcat(wb, "[", 1);
+    wb->json.stack[wb->json.depth].count++;
+
+    _buffer_json_depth_push(wb, BUFFER_JSON_ARRAY);
+}
+
+static inline void buffer_json_add_array_item_string(BUFFER *wb, const char *value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_json_add_string_value(wb, value);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_double(BUFFER *wb, NETDATA_DOUBLE value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_netdata_double(wb, value);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_int64(BUFFER *wb, int64_t value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_int64(wb, value);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_uint64(BUFFER *wb, uint64_t value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_uint64(wb, value);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_time_t(BUFFER *wb, time_t value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_int64(wb, value);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_time_ms(BUFFER *wb, time_t value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_int64(wb, value);
+    buffer_fast_strcat(wb, "000", 3);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_time_t2ms(BUFFER *wb, time_t value) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_print_int64(wb, value);
+    buffer_fast_strcat(wb, "000", 3);
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_add_array_item_object(BUFFER *wb) {
+    if(wb->json.stack[wb->json.depth].count)
+        buffer_fast_strcat(wb, ",", 1);
+
+    buffer_fast_strcat(wb, "{", 1);
+    wb->json.stack[wb->json.depth].count++;
+
+    _buffer_json_depth_push(wb, BUFFER_JSON_OBJECT);
+}
+
+static inline void buffer_json_member_add_time_t(BUFFER *wb, const char *key, time_t value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_print_int64(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_time_t2ms(BUFFER *wb, const char *key, time_t value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_print_int64(wb, value);
+    buffer_fast_strcat(wb, "000", 3);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_uint64(BUFFER *wb, const char *key, uint64_t value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_print_uint64(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_int64(BUFFER *wb, const char *key, int64_t value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_print_int64(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_member_add_double(BUFFER *wb, const char *key, NETDATA_DOUBLE value) {
+    buffer_print_json_comma_newline_spacing(wb);
+    buffer_print_json_key(wb, key);
+    buffer_fast_strcat(wb, ":", 1);
+    buffer_print_netdata_double(wb, value);
+
+    wb->json.stack[wb->json.depth].count++;
+}
+
+static inline void buffer_json_array_close(BUFFER *wb) {
+#ifdef NETDATA_INTERNAL_CHECKS
+    assert(wb->json.depth >= 0 && "BUFFER JSON: nothing is open to close it");
+    assert(wb->json.stack[wb->json.depth].type == BUFFER_JSON_ARRAY && "BUFFER JSON: an array is not open to close it");
+#endif
+    buffer_fast_strcat(wb, "]", 1);
+    _buffer_json_depth_pop(wb);
 }
 
 #endif /* NETDATA_WEB_BUFFER_H */