Merging upstream version 1.11.0+dfsg.

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

5 files changed, 970 insertions, 0 deletions

diff --git a/libnetdata/buffer/Makefile.am b/libnetdata/buffer/Makefile.am
new file mode 100644
index 00000000..1cb69ed9
--- /dev/null
+++ b/libnetdata/buffer/Makefile.am
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
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+MAINTAINERCLEANFILES = $(srcdir)/Makefile.in
+
+
+dist_noinst_DATA = \
+	README.md \
+	$(NULL)
diff --git a/libnetdata/buffer/Makefile.in b/libnetdata/buffer/Makefile.in
new file mode 100644
index 00000000..21bbd3cc
--- /dev/null
+++ b/libnetdata/buffer/Makefile.in
@@ -0,0 +1,464 @@
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diff --git a/libnetdata/buffer/README.md b/libnetdata/buffer/README.md
new file mode 100644
index 00000000..a7cfef89
--- /dev/null
+++ b/libnetdata/buffer/README.md
@@ -0,0 +1,11 @@
+# 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.
\ No newline at end of file
diff --git a/libnetdata/buffer/buffer.c b/libnetdata/buffer/buffer.c
new file mode 100644
index 00000000..50672324
--- /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, "&lt;"); break;
+            case '>': buffer_strcat(wb, "&gt;"); break;
+            case '"': buffer_strcat(wb, "&quot;"); break;
+            case '/': buffer_strcat(wb, "&#x2F;"); break;
+            case '\'': buffer_strcat(wb, "&#x27;"); 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 00000000..8e431bfd
--- /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 */