src/libnetdata/buffer/buffer.c
// SPDX-License-Identifier: GPL-3.0-or-later
#include "../libnetdata.h"
static inline void buffer_overflow_init(BUFFER *b)
{
b->buffer[b->size] = '\0';
strcpy(&b->buffer[b->size + 1], BUFFER_OVERFLOW_EOF);
}
void buffer_reset(BUFFER *wb) {
buffer_flush(wb);
wb->content_type = CT_TEXT_PLAIN;
wb->options = 0;
wb->date = 0;
wb->expires = 0;
buffer_no_cacheable(wb);
buffer_overflow_check(wb);
}
void buffer_char_replace(BUFFER *wb, char from, char to) {
char *s = wb->buffer, *end = &wb->buffer[wb->len];
while(s != end) {
if(*s == from) *s = to;
s++;
}
buffer_overflow_check(wb);
}
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;
}
size_t printed = 0;
if(likely(send_anomaly_bit && (flags & SN_FLAG_NOT_ANOMALOUS))) {
buffer_fast_strcat(wb, "A", 1);
printed++;
}
if(unlikely(flags & SN_FLAG_RESET)) {
buffer_fast_strcat(wb, "R", 1);
printed++;
}
if(!printed)
buffer_fast_strcat(wb, "''", 2);
}
void buffer_strcat_htmlescape(BUFFER *wb, const char *txt)
{
while(*txt) {
switch(*txt) {
case '&': buffer_strcat(wb, "&"); break;
case '<': buffer_strcat(wb, "<"); break;
case '>': buffer_strcat(wb, ">"); break;
case '"': buffer_strcat(wb, """); break;
case '/': buffer_strcat(wb, "/"); break;
case '\'': buffer_strcat(wb, "'"); break;
default: {
buffer_need_bytes(wb, 1);
wb->buffer[wb->len++] = *txt;
}
}
txt++;
}
buffer_overflow_check(wb);
}
void buffer_snprintf(BUFFER *wb, size_t len, const char *fmt, ...)
{
if(unlikely(!fmt || !*fmt)) return;
buffer_need_bytes(wb, len + 1);
va_list args;
va_start(args, fmt);
// vsnprintfz() returns the number of bytes actually written - after possible truncation
wb->len += vsnprintfz(&wb->buffer[wb->len], len, fmt, args);
va_end(args);
buffer_overflow_check(wb);
// the buffer is \0 terminated by vsnprintfz
}
inline void buffer_vsprintf(BUFFER *wb, const char *fmt, va_list args) {
if(unlikely(!fmt || !*fmt)) return;
size_t full_size_bytes = 0, need = 2, space_remaining = 0;
do {
need += full_size_bytes + 2;
buffer_need_bytes(wb, need);
space_remaining = wb->size - wb->len - 1;
// Use the copy of va_list for vsnprintf
va_list args_copy;
va_copy(args_copy, args);
// vsnprintf() returns the number of bytes required, even if bigger than the buffer provided
full_size_bytes = (size_t) vsnprintf(&wb->buffer[wb->len], space_remaining, fmt, args_copy);
va_end(args_copy);
} while(full_size_bytes >= space_remaining);
wb->len += full_size_bytes;
wb->buffer[wb->len] = '\0';
buffer_overflow_check(wb);
}
void buffer_sprintf(BUFFER *wb, const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
buffer_vsprintf(wb, fmt, args);
va_end(args);
}
// 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)
{
// 10 20 30 = 35
// 01234567890123456789012345678901234
// Date(2014,04,01,03,28,20)
buffer_need_bytes(wb, 30);
char *b = &wb->buffer[wb->len], *p;
unsigned int *q = (unsigned int *)b;
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
*q++ = 0x65746144; // "Date" backwards.
#else
*q++ = 0x44617465; // "Date"
#endif
p = (char *)q;
*p++ = '(';
*p++ = '0' + year / 1000; year %= 1000;
*p++ = '0' + year / 100; year %= 100;
*p++ = '0' + year / 10;
*p++ = '0' + year % 10;
*p++ = ',';
*p = '0' + month / 10; if (*p != '0') p++;
*p++ = '0' + month % 10;
*p++ = ',';
*p = '0' + day / 10; if (*p != '0') p++;
*p++ = '0' + day % 10;
*p++ = ',';
*p = '0' + hours / 10; if (*p != '0') p++;
*p++ = '0' + hours % 10;
*p++ = ',';
*p = '0' + minutes / 10; if (*p != '0') p++;
*p++ = '0' + minutes % 10;
*p++ = ',';
*p = '0' + seconds / 10; if (*p != '0') p++;
*p++ = '0' + seconds % 10;
unsigned short *r = (unsigned short *)p;
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
*r++ = 0x0029; // ")\0" backwards.
#else
*r++ = 0x2900; // ")\0"
#endif
wb->len += (size_t)((char *)r - b - 1);
// terminate it
wb->buffer[wb->len] = '\0';
buffer_overflow_check(wb);
}
// generate a date, the fastest possible way...
void buffer_date(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds)
{
// 10 20 30 = 35
// 01234567890123456789012345678901234
// 2014-04-01 03:28:20
buffer_need_bytes(wb, 36);
char *b = &wb->buffer[wb->len];
char *p = b;
*p++ = '0' + year / 1000; year %= 1000;
*p++ = '0' + year / 100; year %= 100;
*p++ = '0' + year / 10;
*p++ = '0' + year % 10;
*p++ = '-';
*p++ = '0' + month / 10;
*p++ = '0' + month % 10;
*p++ = '-';
*p++ = '0' + day / 10;
*p++ = '0' + day % 10;
*p++ = ' ';
*p++ = '0' + hours / 10;
*p++ = '0' + hours % 10;
*p++ = ':';
*p++ = '0' + minutes / 10;
*p++ = '0' + minutes % 10;
*p++ = ':';
*p++ = '0' + seconds / 10;
*p++ = '0' + seconds % 10;
*p = '\0';
wb->len += (size_t)(p - b);
// terminate it
wb->buffer[wb->len] = '\0';
buffer_overflow_check(wb);
}
BUFFER *buffer_create(size_t size, size_t *statistics)
{
BUFFER *b;
netdata_log_debug(D_WEB_BUFFER, "Creating new web buffer of size %zu.", size);
b = callocz(1, sizeof(BUFFER));
b->buffer = mallocz(size + sizeof(BUFFER_OVERFLOW_EOF) + 2);
b->buffer[0] = '\0';
b->size = size;
b->content_type = CT_TEXT_PLAIN;
b->statistics = statistics;
buffer_no_cacheable(b);
buffer_overflow_init(b);
buffer_overflow_check(b);
if(b->statistics)
__atomic_add_fetch(b->statistics, b->size + sizeof(BUFFER) + sizeof(BUFFER_OVERFLOW_EOF) + 2, __ATOMIC_RELAXED);
return(b);
}
void buffer_free(BUFFER *b) {
if(unlikely(!b)) return;
buffer_overflow_check(b);
netdata_log_debug(D_WEB_BUFFER, "Freeing web buffer of size %zu.", b->size);
if(b->statistics)
__atomic_sub_fetch(b->statistics, b->size + sizeof(BUFFER) + sizeof(BUFFER_OVERFLOW_EOF) + 2, __ATOMIC_RELAXED);
freez(b->buffer);
freez(b);
}
void buffer_increase(BUFFER *b, size_t free_size_required) {
buffer_overflow_check(b);
size_t remaining = b->size - b->len;
if(remaining >= free_size_required) return;
size_t increase = free_size_required - remaining;
size_t minimum = 128;
if(minimum > increase) increase = minimum;
size_t optimal = (b->size > 5*1024*1024) ? b->size / 2 : b->size;
if(optimal > increase) increase = optimal;
netdata_log_debug(D_WEB_BUFFER, "Increasing data buffer from size %zu to %zu.", b->size, b->size + increase);
b->buffer = reallocz(b->buffer, b->size + increase + sizeof(BUFFER_OVERFLOW_EOF) + 2);
b->size += increase;
if(b->statistics)
__atomic_add_fetch(b->statistics, increase, __ATOMIC_RELAXED);
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, BUFFER_JSON_OPTIONS options) {
strncpyz(wb->json.key_quote, key_quote, BUFFER_QUOTE_MAX_SIZE);
strncpyz(wb->json.value_quote, value_quote, BUFFER_QUOTE_MAX_SIZE);
wb->json.depth = (int8_t)(depth - 1);
_buffer_json_depth_push(wb, BUFFER_JSON_OBJECT);
if(add_anonymous_object)
buffer_fast_strcat(wb, "{", 1);
else
options |= BUFFER_JSON_OPTIONS_NON_ANONYMOUS;
wb->json.options = options;
wb->content_type = CT_APPLICATION_JSON;
buffer_no_cacheable(wb);
}
void buffer_json_finalize(BUFFER *wb) {
while(wb->json.depth >= 0) {
switch(wb->json.stack[wb->json.depth].type) {
case BUFFER_JSON_OBJECT:
if (wb->json.depth == 0)
if (!(wb->json.options & BUFFER_JSON_OPTIONS_NON_ANONYMOUS))
buffer_json_object_close(wb);
else
_buffer_json_depth_pop(wb);
else
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.options & BUFFER_JSON_OPTIONS_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)toupper(hex_digits[i])] = i;
hex_value_from_ascii[(int)tolower(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) {
netdata_log_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) {
netdata_log_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) {
netdata_log_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) {
netdata_log_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, BUFFER_JSON_OPTIONS_DEFAULT);
buffer_json_finalize(wb);
errors += buffer_expect(wb, "{\n}\n");
buffer_flush(wb);
buffer_json_initialize(wb, "\"", "\"", 0, true, BUFFER_JSON_OPTIONS_DEFAULT);
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;
}