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diff --git a/include/haproxy/intops.h b/include/haproxy/intops.h
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+/*
+ * include/haproxy/intops.h
+ * Functions for integer operations.
+ *
+ * Copyright (C) 2020 Willy Tarreau - w@1wt.eu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation, version 2.1
+ * exclusively.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+*/
+
+#ifndef _HAPROXY_INTOPS_H
+#define _HAPROXY_INTOPS_H
+
+#include <haproxy/api.h>
+
+/* exported functions, mostly integer parsing */
+/* rounds <i> down to the closest value having max 2 digits */
+unsigned int round_2dig(unsigned int i);
+unsigned int full_hash(unsigned int a);
+int varint_bytes(uint64_t v);
+unsigned int read_uint(const char **s, const char *end);
+long long read_int64(const char **s, const char *end);
+unsigned long long read_uint64(const char **s, const char *end);
+unsigned int str2ui(const char *s);
+unsigned int str2uic(const char *s);
+unsigned int strl2ui(const char *s, int len);
+unsigned int strl2uic(const char *s, int len);
+int strl2ic(const char *s, int len);
+int strl2irc(const char *s, int len, int *ret);
+int strl2llrc(const char *s, int len, long long *ret);
+int strl2llrc_dotted(const char *text, int len, long long *ret);
+unsigned int mask_find_rank_bit(unsigned int r, unsigned long m);
+unsigned int mask_find_rank_bit_fast(unsigned int r, unsigned long m,
+ unsigned long a, unsigned long b,
+ unsigned long c, unsigned long d);
+void mask_prep_rank_map(unsigned long m,
+ unsigned long *a, unsigned long *b,
+ unsigned long *c, unsigned long *d);
+int one_among_mask(unsigned long v, int bit);
+
+
+/* Multiply the two 32-bit operands and shift the 64-bit result right 32 bits.
+ * This is used to compute fixed ratios by setting one of the operands to
+ * (2^32*ratio).
+ */
+static inline unsigned int mul32hi(unsigned int a, unsigned int b)
+{
+ return ((unsigned long long)a * b + a) >> 32;
+}
+
+/* gcc does not know when it can safely divide 64 bits by 32 bits. Use this
+ * function when you know for sure that the result fits in 32 bits, because
+ * it is optimal on x86 and on 64bit processors.
+ */
+static inline unsigned int div64_32(unsigned long long o1, unsigned int o2)
+{
+ unsigned long long result;
+#ifdef __i386__
+ asm("divl %2"
+ : "=A" (result)
+ : "A"(o1), "rm"(o2));
+#else
+ result = o1 / o2;
+#endif
+ return result;
+}
+
+/* rotate left a 64-bit integer by <bits:[0-5]> bits */
+static inline uint64_t rotl64(uint64_t v, uint8_t bits)
+{
+#if !defined(__ARM_ARCH_8A) && !defined(__x86_64__)
+ bits &= 63;
+#endif
+ v = (v << bits) | (v >> (-bits & 63));
+ return v;
+}
+
+/* rotate right a 64-bit integer by <bits:[0-5]> bits */
+static inline uint64_t rotr64(uint64_t v, uint8_t bits)
+{
+#if !defined(__ARM_ARCH_8A) && !defined(__x86_64__)
+ bits &= 63;
+#endif
+ v = (v >> bits) | (v << (-bits & 63));
+ return v;
+}
+
+/* Simple popcountl implementation. It returns the number of ones in a word.
+ * Described here : https://graphics.stanford.edu/~seander/bithacks.html
+ */
+static inline unsigned int my_popcountl(unsigned long a)
+{
+ a = a - ((a >> 1) & ~0UL/3);
+ a = (a & ~0UL/15*3) + ((a >> 2) & ~0UL/15*3);
+ a = (a + (a >> 4)) & ~0UL/255*15;
+ return (unsigned long)(a * (~0UL/255)) >> (sizeof(unsigned long) - 1) * 8;
+}
+
+/* returns non-zero if <a> has at least 2 bits set */
+static inline unsigned long atleast2(unsigned long a)
+{
+ return a & (a - 1);
+}
+
+/* Simple ffs implementation. It returns the position of the lowest bit set to
+ * one, starting at 1. It is illegal to call it with a==0 (undefined result).
+ */
+static inline unsigned int my_ffsl(unsigned long a)
+{
+ unsigned long cnt;
+
+#if defined(__x86_64__)
+ __asm__("bsf %1,%0\n" : "=r" (cnt) : "rm" (a));
+ cnt++;
+#else
+
+ cnt = 1;
+#if LONG_MAX > 0x7FFFFFFFL /* 64bits */
+ if (!(a & 0xFFFFFFFFUL)) {
+ a >>= 32;
+ cnt += 32;
+ }
+#endif
+ if (!(a & 0XFFFFU)) {
+ a >>= 16;
+ cnt += 16;
+ }
+ if (!(a & 0XFF)) {
+ a >>= 8;
+ cnt += 8;
+ }
+ if (!(a & 0xf)) {
+ a >>= 4;
+ cnt += 4;
+ }
+ if (!(a & 0x3)) {
+ a >>= 2;
+ cnt += 2;
+ }
+ if (!(a & 0x1)) {
+ cnt += 1;
+ }
+#endif /* x86_64 */
+
+ return cnt;
+}
+
+/* Simple fls implementation. It returns the position of the highest bit set to
+ * one, starting at 1. It is illegal to call it with a==0 (undefined result).
+ */
+static inline unsigned int my_flsl(unsigned long a)
+{
+ unsigned long cnt;
+
+#if defined(__x86_64__)
+ __asm__("bsr %1,%0\n" : "=r" (cnt) : "rm" (a));
+ cnt++;
+#else
+
+ cnt = 1;
+#if LONG_MAX > 0x7FFFFFFFUL /* 64bits */
+ if (a & 0xFFFFFFFF00000000UL) {
+ a >>= 32;
+ cnt += 32;
+ }
+#endif
+ if (a & 0XFFFF0000U) {
+ a >>= 16;
+ cnt += 16;
+ }
+ if (a & 0XFF00) {
+ a >>= 8;
+ cnt += 8;
+ }
+ if (a & 0xf0) {
+ a >>= 4;
+ cnt += 4;
+ }
+ if (a & 0xc) {
+ a >>= 2;
+ cnt += 2;
+ }
+ if (a & 0x2) {
+ cnt += 1;
+ }
+#endif /* x86_64 */
+
+ return cnt;
+}
+
+/* Build a word with the <bits> lower bits set (reverse of my_popcountl) */
+static inline unsigned long nbits(int bits)
+{
+ if (--bits < 0)
+ return 0;
+ else
+ return (2UL << bits) - 1;
+}
+
+/* Turns 64-bit value <a> from host byte order to network byte order.
+ * The principle consists in letting the compiler detect we're playing
+ * with a union and simplify most or all operations. The asm-optimized
+ * htonl() version involving bswap (x86) / rev (arm) / other is a single
+ * operation on little endian, or a NOP on big-endian. In both cases,
+ * this lets the compiler "see" that we're rebuilding a 64-bit word from
+ * two 32-bit quantities that fit into a 32-bit register. In big endian,
+ * the whole code is optimized out. In little endian, with a decent compiler,
+ * a few bswap and 2 shifts are left, which is the minimum acceptable.
+ */
+static inline unsigned long long my_htonll(unsigned long long a)
+{
+#if defined(__x86_64__)
+ __asm__ volatile("bswapq %0" : "=r"(a) : "0"(a));
+ return a;
+#else
+ union {
+ struct {
+ unsigned int w1;
+ unsigned int w2;
+ } by32;
+ unsigned long long by64;
+ } w = { .by64 = a };
+ return ((unsigned long long)htonl(w.by32.w1) << 32) | htonl(w.by32.w2);
+#endif
+}
+
+/* Turns 64-bit value <a> from network byte order to host byte order. */
+static inline unsigned long long my_ntohll(unsigned long long a)
+{
+ return my_htonll(a);
+}
+
+/* sets bit <bit> into map <map>, which must be long-aligned */
+static inline void ha_bit_set(unsigned long bit, long *map)
+{
+ map[bit / (8 * sizeof(*map))] |= 1UL << (bit & (8 * sizeof(*map) - 1));
+}
+
+/* clears bit <bit> from map <map>, which must be long-aligned */
+static inline void ha_bit_clr(unsigned long bit, long *map)
+{
+ map[bit / (8 * sizeof(*map))] &= ~(1UL << (bit & (8 * sizeof(*map) - 1)));
+}
+
+/* flips bit <bit> from map <map>, which must be long-aligned */
+static inline void ha_bit_flip(unsigned long bit, long *map)
+{
+ map[bit / (8 * sizeof(*map))] ^= 1UL << (bit & (8 * sizeof(*map) - 1));
+}
+
+/* returns non-zero if bit <bit> from map <map> is set, otherwise 0 */
+static inline int ha_bit_test(unsigned long bit, const long *map)
+{
+ return !!(map[bit / (8 * sizeof(*map))] & 1UL << (bit & (8 * sizeof(*map) - 1)));
+}
+
+/* hash a 32-bit integer to another 32-bit integer. This code may be large when
+ * inlined, use full_hash() instead.
+ */
+static inline unsigned int __full_hash(unsigned int a)
+{
+ /* This function is one of Bob Jenkins' full avalanche hashing
+ * functions, which when provides quite a good distribution for little
+ * input variations. The result is quite suited to fit over a 32-bit
+ * space with enough variations so that a randomly picked number falls
+ * equally before any server position.
+ * Check http://burtleburtle.net/bob/hash/integer.html for more info.
+ */
+ a = (a+0x7ed55d16) + (a<<12);
+ a = (a^0xc761c23c) ^ (a>>19);
+ a = (a+0x165667b1) + (a<<5);
+ a = (a+0xd3a2646c) ^ (a<<9);
+ a = (a+0xfd7046c5) + (a<<3);
+ a = (a^0xb55a4f09) ^ (a>>16);
+
+ /* ensure values are better spread all around the tree by multiplying
+ * by a large prime close to 3/4 of the tree.
+ */
+ return a * 3221225473U;
+}
+
+/*
+ * Return integer equivalent of character <c> for a hex digit (0-9, a-f, A-F),
+ * otherwise -1. This compact form helps gcc produce efficient code.
+ */
+static inline int hex2i(int c)
+{
+ if ((unsigned char)(c -= '0') > 9) {
+ if ((unsigned char)(c -= 'A' - '0') > 5 &&
+ (unsigned char)(c -= 'a' - 'A') > 5)
+ c = -11;
+ c += 10;
+ }
+ return c;
+}
+
+/* This one is 6 times faster than strtoul() on athlon, but does
+ * no check at all.
+ */
+static inline unsigned int __str2ui(const char *s)
+{
+ unsigned int i = 0;
+ while (*s) {
+ i = i * 10 - '0';
+ i += (unsigned char)*s++;
+ }
+ return i;
+}
+
+/* This one is 5 times faster than strtoul() on athlon with checks.
+ * It returns the value of the number composed of all valid digits read.
+ */
+static inline unsigned int __str2uic(const char *s)
+{
+ unsigned int i = 0;
+ unsigned int j;
+
+ while (1) {
+ j = (*s++) - '0';
+ if (j > 9)
+ break;
+ i *= 10;
+ i += j;
+ }
+ return i;
+}
+
+/* This one is 28 times faster than strtoul() on athlon, but does
+ * no check at all!
+ */
+static inline unsigned int __strl2ui(const char *s, int len)
+{
+ unsigned int i = 0;
+
+ while (len-- > 0) {
+ i = i * 10 - '0';
+ i += (unsigned char)*s++;
+ }
+ return i;
+}
+
+/* This one is 7 times faster than strtoul() on athlon with checks.
+ * It returns the value of the number composed of all valid digits read.
+ */
+static inline unsigned int __strl2uic(const char *s, int len)
+{
+ unsigned int i = 0;
+ unsigned int j, k;
+
+ while (len-- > 0) {
+ j = (*s++) - '0';
+ k = i * 10;
+ if (j > 9)
+ break;
+ i = k + j;
+ }
+ return i;
+}
+
+/* This function reads an unsigned integer from the string pointed to by <s>
+ * and returns it. The <s> pointer is adjusted to point to the first unread
+ * char. The function automatically stops at <end>.
+ */
+static inline unsigned int __read_uint(const char **s, const char *end)
+{
+ const char *ptr = *s;
+ unsigned int i = 0;
+ unsigned int j, k;
+
+ while (ptr < end) {
+ j = *ptr - '0';
+ k = i * 10;
+ if (j > 9)
+ break;
+ i = k + j;
+ ptr++;
+ }
+ *s = ptr;
+ return i;
+}
+
+/* returns the number of bytes needed to encode <v> as a varint. Be careful, use
+ * it only with constants as it generates a large code (typ. 180 bytes). Use the
+ * varint_bytes() version instead in case of doubt.
+ */
+static inline int __varint_bytes(uint64_t v)
+{
+ switch (v) {
+ case 0x0000000000000000ULL ... 0x00000000000000efULL: return 1;
+ case 0x00000000000000f0ULL ... 0x00000000000008efULL: return 2;
+ case 0x00000000000008f0ULL ... 0x00000000000408efULL: return 3;
+ case 0x00000000000408f0ULL ... 0x00000000020408efULL: return 4;
+ case 0x00000000020408f0ULL ... 0x00000001020408efULL: return 5;
+ case 0x00000001020408f0ULL ... 0x00000081020408efULL: return 6;
+ case 0x00000081020408f0ULL ... 0x00004081020408efULL: return 7;
+ case 0x00004081020408f0ULL ... 0x00204081020408efULL: return 8;
+ case 0x00204081020408f0ULL ... 0x10204081020408efULL: return 9;
+ default: return 10;
+ }
+}
+
+/* Encode the integer <i> into a varint (variable-length integer). The encoded
+ * value is copied in <*buf>. Here is the encoding format:
+ *
+ * 0 <= X < 240 : 1 byte (7.875 bits) [ XXXX XXXX ]
+ * 240 <= X < 2288 : 2 bytes (11 bits) [ 1111 XXXX ] [ 0XXX XXXX ]
+ * 2288 <= X < 264432 : 3 bytes (18 bits) [ 1111 XXXX ] [ 1XXX XXXX ] [ 0XXX XXXX ]
+ * 264432 <= X < 33818864 : 4 bytes (25 bits) [ 1111 XXXX ] [ 1XXX XXXX ]*2 [ 0XXX XXXX ]
+ * 33818864 <= X < 4328786160 : 5 bytes (32 bits) [ 1111 XXXX ] [ 1XXX XXXX ]*3 [ 0XXX XXXX ]
+ * ...
+ *
+ * On success, it returns the number of written bytes and <*buf> is moved after
+ * the encoded value. Otherwise, it returns -1. */
+static inline int encode_varint(uint64_t i, char **buf, char *end)
+{
+ unsigned char *p = (unsigned char *)*buf;
+ int r;
+
+ if (p >= (unsigned char *)end)
+ return -1;
+
+ if (i < 240) {
+ *p++ = i;
+ *buf = (char *)p;
+ return 1;
+ }
+
+ *p++ = (unsigned char)i | 240;
+ i = (i - 240) >> 4;
+ while (i >= 128) {
+ if (p >= (unsigned char *)end)
+ return -1;
+ *p++ = (unsigned char)i | 128;
+ i = (i - 128) >> 7;
+ }
+
+ if (p >= (unsigned char *)end)
+ return -1;
+ *p++ = (unsigned char)i;
+
+ r = ((char *)p - *buf);
+ *buf = (char *)p;
+ return r;
+}
+
+/* Decode a varint from <*buf> and save the decoded value in <*i>. See
+ * 'spoe_encode_varint' for details about varint.
+ * On success, it returns the number of read bytes and <*buf> is moved after the
+ * varint. Otherwise, it returns -1. */
+static inline int decode_varint(char **buf, char *end, uint64_t *i)
+{
+ unsigned char *p = (unsigned char *)*buf;
+ int r;
+
+ if (p >= (unsigned char *)end)
+ return -1;
+
+ *i = *p++;
+ if (*i < 240) {
+ *buf = (char *)p;
+ return 1;
+ }
+
+ r = 4;
+ do {
+ if (p >= (unsigned char *)end)
+ return -1;
+ *i += (uint64_t)*p << r;
+ r += 7;
+ } while (*p++ >= 128);
+
+ r = ((char *)p - *buf);
+ *buf = (char *)p;
+ return r;
+}
+
+#endif /* _HAPROXY_INTOPS_H */
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ */
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