diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:22:31 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:22:31 +0000 |
commit | 8d4f58e49b9dc7d3545651023a36729de773ad86 (patch) | |
tree | 7bc7be4a8e9e298daa1349348400aa2a653866f2 /libnetdata/buffer | |
parent | Initial commit. (diff) | |
download | netdata-upstream.tar.xz netdata-upstream.zip |
Adding upstream version 1.12.0.upstream/1.12.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | libnetdata/buffer/Makefile.am | 9 | ||||
-rw-r--r-- | libnetdata/buffer/README.md | 12 | ||||
-rw-r--r-- | libnetdata/buffer/buffer.c | 401 | ||||
-rw-r--r-- | libnetdata/buffer/buffer.h | 85 |
4 files changed, 507 insertions, 0 deletions
diff --git a/libnetdata/buffer/Makefile.am b/libnetdata/buffer/Makefile.am new file mode 100644 index 0000000..1cb69ed --- /dev/null +++ b/libnetdata/buffer/Makefile.am @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-3.0-or-later + +AUTOMAKE_OPTIONS = subdir-objects +MAINTAINERCLEANFILES = $(srcdir)/Makefile.in + + +dist_noinst_DATA = \ + README.md \ + $(NULL) diff --git a/libnetdata/buffer/README.md b/libnetdata/buffer/README.md new file mode 100644 index 0000000..48072e9 --- /dev/null +++ b/libnetdata/buffer/README.md @@ -0,0 +1,12 @@ +# BUFFER + +`BUFFER` is a convenience library for working with strings in `C`. +Mainly, `BUFFER`s eliminate the need for tracking the string length, thus providing +a safe alternative for string operations. + +Also, they are super fast in printing and appending data to the string and its `buffer_strlen()` +is just a lookup (it does not traverse the string). + +Netdata uses `BUFFER`s for preparing web responses and buffering data to be sent upstream or +to backend databases. +[![analytics](https://www.google-analytics.com/collect?v=1&aip=1&t=pageview&_s=1&ds=github&dr=https%3A%2F%2Fgithub.com%2Fnetdata%2Fnetdata&dl=https%3A%2F%2Fmy-netdata.io%2Fgithub%2Flibnetdata%2Fbuffer%2FREADME&_u=MAC~&cid=5792dfd7-8dc4-476b-af31-da2fdb9f93d2&tid=UA-64295674-3)]() diff --git a/libnetdata/buffer/buffer.c b/libnetdata/buffer/buffer.c new file mode 100644 index 0000000..5067232 --- /dev/null +++ b/libnetdata/buffer/buffer.c @@ -0,0 +1,401 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#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) +{ + buffer_flush(wb); + + wb->contenttype = CT_TEXT_PLAIN; + wb->options = 0; + wb->date = 0; + wb->expires = 0; + + buffer_overflow_check(wb); +} + +const char *buffer_tostring(BUFFER *wb) +{ + buffer_need_bytes(wb, 1); + wb->buffer[wb->len] = '\0'; + + buffer_overflow_check(wb); + + return(wb->buffer); +} + +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); +} + +// This trick seems to give an 80% speed increase in 32bit systems +// print_calculated_number_llu_r() will just print the digits up to the +// point the remaining value fits in 32 bits, and then calls +// print_calculated_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) { +#ifdef ENVIRONMENT32 + if(uvalue > (unsigned long long)0xffffffff) + str = print_number_llu_r(str, uvalue); + else + str = print_number_lu_r(str, uvalue); +#else + do *str++ = (char)('0' + (uvalue % 10)); while(uvalue /= 10); +#endif + + 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; + +#ifdef ENVIRONMENT32 + if(uvalue > (unsigned long long)0xffffffff) + wstr = print_number_llu_r(wstr, uvalue); + else + wstr = print_number_lu_r(wstr, uvalue); +#else + do *wstr++ = (char)('0' + (uvalue % 10)); while(uvalue /= 10); +#endif + + // 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_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_increase(wb, len); + buffer_strcat(wb, txt); + } + else { + // terminate the string + // without increasing the length + buffer_need_bytes(wb, (size_t)1); + wb->buffer[wb->len] = '\0'; + } +} + +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); + wb->len += vsnprintfz(&wb->buffer[wb->len], len, fmt, args); + va_end(args); + + buffer_overflow_check(wb); + + // the buffer is \0 terminated by vsnprintfz +} + +void buffer_vsprintf(BUFFER *wb, const char *fmt, va_list args) +{ + if(unlikely(!fmt || !*fmt)) return; + + buffer_need_bytes(wb, 2); + + size_t len = wb->size - wb->len - 1; + + wb->len += vsnprintfz(&wb->buffer[wb->len], len, fmt, args); + + buffer_overflow_check(wb); + + // the buffer is \0 terminated by vsnprintfz +} + +void buffer_sprintf(BUFFER *wb, const char *fmt, ...) +{ + if(unlikely(!fmt || !*fmt)) return; + + va_list args; + size_t wrote = 0, need = 2, multiplier = 0, len; + + do { + need += wrote + multiplier * WEB_DATA_LENGTH_INCREASE_STEP; + multiplier++; + + debug(D_WEB_BUFFER, "web_buffer_sprintf(): increasing web_buffer at position %zu, size = %zu, by %zu bytes (wrote = %zu)\n", wb->len, wb->size, need, wrote); + buffer_need_bytes(wb, need); + + len = wb->size - wb->len - 1; + + va_start(args, fmt); + wrote = (size_t) vsnprintfz(&wb->buffer[wb->len], len, fmt, args); + va_end(args); + + } while(wrote >= len); + + wb->len += wrote; + + // the buffer is \0 terminated by vsnprintf +} + + +void buffer_rrd_value(BUFFER *wb, calculated_number value) +{ + buffer_need_bytes(wb, 50); + + if(isnan(value) || isinf(value)) { + buffer_strcat(wb, "null"); + return; + } + else + wb->len += print_calculated_number(&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) +{ + // 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) +{ + BUFFER *b; + + 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->contenttype = CT_TEXT_PLAIN; + buffer_overflow_init(b); + buffer_overflow_check(b); + + return(b); +} + +void buffer_free(BUFFER *b) { + if(unlikely(!b)) return; + + buffer_overflow_check(b); + + debug(D_WEB_BUFFER, "Freeing web buffer of size %zu.", b->size); + + freez(b->buffer); + freez(b); +} + +void buffer_increase(BUFFER *b, size_t free_size_required) { + buffer_overflow_check(b); + + size_t left = b->size - b->len; + + if(left >= free_size_required) return; + + size_t increase = free_size_required - left; + if(increase < WEB_DATA_LENGTH_INCREASE_STEP) increase = WEB_DATA_LENGTH_INCREASE_STEP; + + 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; + + buffer_overflow_init(b); + buffer_overflow_check(b); +} diff --git a/libnetdata/buffer/buffer.h b/libnetdata/buffer/buffer.h new file mode 100644 index 0000000..8e431bf --- /dev/null +++ b/libnetdata/buffer/buffer.h @@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#ifndef NETDATA_WEB_BUFFER_H +#define NETDATA_WEB_BUFFER_H 1 + +#include "../libnetdata.h" + +#define WEB_DATA_LENGTH_INCREASE_STEP 1024 + +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 +} 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 + +#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) + +#define buffer_strlen(wb) ((wb)->len) +extern const char *buffer_tostring(BUFFER *wb); + +#define buffer_flush(wb) wb->buffer[(wb)->len = 0] = '\0' +extern void buffer_reset(BUFFER *wb); + +extern void buffer_strcat(BUFFER *wb, const char *txt); +extern void buffer_rrd_value(BUFFER *wb, calculated_number value); + +extern void buffer_date(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds); +extern void buffer_jsdate(BUFFER *wb, int year, int month, int day, int hours, int minutes, int seconds); + +extern BUFFER *buffer_create(size_t size); +extern void buffer_free(BUFFER *b); +extern void buffer_increase(BUFFER *b, size_t free_size_required); + +extern void buffer_snprintf(BUFFER *wb, size_t len, const char *fmt, ...) PRINTFLIKE(3, 4); +extern void buffer_vsprintf(BUFFER *wb, const char *fmt, va_list args); +extern void buffer_sprintf(BUFFER *wb, const char *fmt, ...) PRINTFLIKE(2,3); +extern void buffer_strcat_htmlescape(BUFFER *wb, const char *txt); + +extern void buffer_char_replace(BUFFER *wb, char from, char to); + +extern char *print_number_lu_r(char *str, unsigned long uvalue); +extern char *print_number_llu_r(char *str, unsigned long long uvalue); +extern char *print_number_llu_r_smart(char *str, unsigned long long uvalue); + +extern void buffer_print_llu(BUFFER *wb, unsigned long long uvalue); + +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); +} + +#endif /* NETDATA_WEB_BUFFER_H */ |