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Extract simple integer math into its own module
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@ -173,6 +173,8 @@ uptime-*.json
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/src/lib/libtor-ctime-testing.a
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/src/lib/libtor-err.a
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/src/lib/libtor-err-testing.a
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/src/lib/libtor-intmath.a
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/src/lib/libtor-intmath-testing.a
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/src/lib/libtor-malloc.a
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/src/lib/libtor-malloc-testing.a
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/src/lib/libtor-string.a
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@ -45,6 +45,7 @@ TOR_UTIL_LIBS = \
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src/lib/libtor-malloc.a \
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src/lib/libtor-wallclock.a \
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src/lib/libtor-err.a \
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src/lib/libtor-intmath.a \
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src/lib/libtor-ctime.a
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# Variants of the above for linking the testing variant of tor (for coverage
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@ -56,6 +57,7 @@ TOR_UTIL_TESTING_LIBS = \
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src/lib/libtor-malloc-testing.a \
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src/lib/libtor-wallclock-testing.a \
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src/lib/libtor-err-testing.a \
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src/lib/libtor-intmath.a \
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src/lib/libtor-ctime-testing.a
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# Internal crypto libraries used in Tor
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@ -166,105 +166,6 @@ tor_llround(double d)
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#endif /* defined(HAVE_LLROUND) || ... */
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}
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/** Returns floor(log2(u64)). If u64 is 0, (incorrectly) returns 0. */
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int
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tor_log2(uint64_t u64)
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{
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int r = 0;
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if (u64 >= (U64_LITERAL(1)<<32)) {
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u64 >>= 32;
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r = 32;
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}
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if (u64 >= (U64_LITERAL(1)<<16)) {
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u64 >>= 16;
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r += 16;
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}
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if (u64 >= (U64_LITERAL(1)<<8)) {
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u64 >>= 8;
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r += 8;
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}
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if (u64 >= (U64_LITERAL(1)<<4)) {
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u64 >>= 4;
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r += 4;
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}
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if (u64 >= (U64_LITERAL(1)<<2)) {
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u64 >>= 2;
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r += 2;
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}
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if (u64 >= (U64_LITERAL(1)<<1)) {
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// u64 >>= 1; // not using this any more.
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r += 1;
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}
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return r;
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}
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/** Return the power of 2 in range [1,UINT64_MAX] closest to <b>u64</b>. If
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* there are two powers of 2 equally close, round down. */
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uint64_t
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round_to_power_of_2(uint64_t u64)
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{
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int lg2;
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uint64_t low;
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uint64_t high;
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if (u64 == 0)
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return 1;
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lg2 = tor_log2(u64);
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low = U64_LITERAL(1) << lg2;
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if (lg2 == 63)
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return low;
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high = U64_LITERAL(1) << (lg2+1);
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if (high - u64 < u64 - low)
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return high;
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else
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return low;
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}
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/** Return the lowest x such that x is at least <b>number</b>, and x modulo
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* <b>divisor</b> == 0. If no such x can be expressed as an unsigned, return
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* UINT_MAX. Asserts if divisor is zero. */
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unsigned
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round_to_next_multiple_of(unsigned number, unsigned divisor)
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{
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tor_assert(divisor > 0);
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if (UINT_MAX - divisor + 1 < number)
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return UINT_MAX;
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number += divisor - 1;
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number -= number % divisor;
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return number;
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}
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/** Return the lowest x such that x is at least <b>number</b>, and x modulo
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* <b>divisor</b> == 0. If no such x can be expressed as a uint32_t, return
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* UINT32_MAX. Asserts if divisor is zero. */
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uint32_t
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round_uint32_to_next_multiple_of(uint32_t number, uint32_t divisor)
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{
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tor_assert(divisor > 0);
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if (UINT32_MAX - divisor + 1 < number)
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return UINT32_MAX;
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number += divisor - 1;
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number -= number % divisor;
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return number;
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}
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/** Return the lowest x such that x is at least <b>number</b>, and x modulo
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* <b>divisor</b> == 0. If no such x can be expressed as a uint64_t, return
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* UINT64_MAX. Asserts if divisor is zero. */
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uint64_t
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round_uint64_to_next_multiple_of(uint64_t number, uint64_t divisor)
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{
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tor_assert(divisor > 0);
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if (UINT64_MAX - divisor + 1 < number)
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return UINT64_MAX;
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number += divisor - 1;
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number -= number % divisor;
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return number;
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}
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/** Transform a random value <b>p</b> from the uniform distribution in
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* [0.0, 1.0[ into a Laplace distributed value with location parameter
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* <b>mu</b> and scale parameter <b>b</b>. Truncate the final result
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@ -319,68 +220,6 @@ add_laplace_noise(int64_t signal_, double random_, double delta_f,
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return signal_ + noise;
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}
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/* Helper: safely add two uint32_t's, capping at UINT32_MAX rather
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* than overflow */
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uint32_t
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tor_add_u32_nowrap(uint32_t a, uint32_t b)
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{
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/* a+b > UINT32_MAX check, without overflow */
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if (PREDICT_UNLIKELY(a > UINT32_MAX - b)) {
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return UINT32_MAX;
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} else {
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return a+b;
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}
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}
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/* Helper: return greatest common divisor of a,b */
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static uint64_t
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gcd64(uint64_t a, uint64_t b)
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{
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while (b) {
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uint64_t t = b;
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b = a % b;
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a = t;
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}
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return a;
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}
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/* Given a fraction *<b>numer</b> / *<b>denom</b>, simplify it.
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* Requires that the denominator is greater than 0. */
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void
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simplify_fraction64(uint64_t *numer, uint64_t *denom)
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{
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tor_assert(denom);
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uint64_t gcd = gcd64(*numer, *denom);
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*numer /= gcd;
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*denom /= gcd;
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}
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/** Return the number of bits set in <b>v</b>. */
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int
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n_bits_set_u8(uint8_t v)
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{
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static const int nybble_table[] = {
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0, /* 0000 */
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1, /* 0001 */
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1, /* 0010 */
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2, /* 0011 */
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1, /* 0100 */
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2, /* 0101 */
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2, /* 0110 */
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3, /* 0111 */
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1, /* 1000 */
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2, /* 1001 */
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2, /* 1010 */
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3, /* 1011 */
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2, /* 1100 */
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3, /* 1101 */
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3, /* 1110 */
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4, /* 1111 */
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};
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return nybble_table[v & 15] + nybble_table[v>>4];
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}
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/* =====
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* String manipulation
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* ===== */
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@ -27,6 +27,10 @@
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#include "lib/wallclock/approx_time.h"
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#include "lib/string/util_string.h"
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#include "lib/string/scanf.h"
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#include "lib/intmath/bits.h"
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#include "lib/intmath/addsub.h"
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#include "lib/intmath/muldiv.h"
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#include "lib/intmath/cmp.h"
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#include "common/util_bug.h"
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#ifndef O_BINARY
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@ -66,35 +70,10 @@ void tor_log_mallinfo(int severity);
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double tor_mathlog(double d) ATTR_CONST;
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long tor_lround(double d) ATTR_CONST;
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int64_t tor_llround(double d) ATTR_CONST;
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int tor_log2(uint64_t u64) ATTR_CONST;
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uint64_t round_to_power_of_2(uint64_t u64);
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unsigned round_to_next_multiple_of(unsigned number, unsigned divisor);
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uint32_t round_uint32_to_next_multiple_of(uint32_t number, uint32_t divisor);
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uint64_t round_uint64_to_next_multiple_of(uint64_t number, uint64_t divisor);
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int64_t sample_laplace_distribution(double mu, double b, double p);
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int64_t add_laplace_noise(int64_t signal, double random, double delta_f,
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double epsilon);
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int n_bits_set_u8(uint8_t v);
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int64_t clamp_double_to_int64(double number);
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void simplify_fraction64(uint64_t *numer, uint64_t *denom);
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uint32_t tor_add_u32_nowrap(uint32_t a, uint32_t b);
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/* Compute the CEIL of <b>a</b> divided by <b>b</b>, for nonnegative <b>a</b>
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* and positive <b>b</b>. Works on integer types only. Not defined if a+(b-1)
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* can overflow. */
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#define CEIL_DIV(a,b) (((a)+((b)-1))/(b))
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/* Return <b>v</b> if it's between <b>min</b> and <b>max</b>. Otherwise
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* return <b>min</b> if <b>v</b> is smaller than <b>min</b>, or <b>max</b> if
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* <b>b</b> is larger than <b>max</b>.
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*
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* Requires that <b>min</b> is no more than <b>max</b>. May evaluate any of
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* its arguments more than once! */
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#define CLAMP(min,v,max) \
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( ((v) < (min)) ? (min) : \
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((v) > (max)) ? (max) : \
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(v) )
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/* String manipulation */
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@ -7,6 +7,7 @@ include src/lib/container/include.am
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include src/lib/crypt_ops/include.am
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include src/lib/defs/include.am
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include src/lib/include.libdonna.am
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include src/lib/intmath/include.am
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include src/lib/malloc/include.am
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include src/lib/string/include.am
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include src/lib/testsupport/include.am
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@ -7,10 +7,10 @@ lib/malloc/*.h
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lib/err/*.h
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lib/string/*.h
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lib/testsupport/testsupport.h
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lib/intmath/*.h
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ht.h
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siphash.h
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# XXX I'd like to remove this.
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common/util.h
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common/util_bug.h
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@ -14,7 +14,7 @@
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#include <stdlib.h>
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#include "lib/malloc/util_malloc.h"
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#include "lib/container/bloomfilt.h"
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#include "common/util.h" // For tor_log2
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#include "lib/intmath/bits.h"
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/** Return a newly allocated digestset_t, optimized to hold a total of
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* <b>max_elements</b> digests with a reasonably low false positive weight. */
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@ -6,6 +6,7 @@ lib/ctime/*.h
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lib/defs/*.h
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lib/malloc/*.h
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lib/err/*.h
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lib/intmath/*.h
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lib/string/*.h
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lib/testsupport/testsupport.h
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@ -15,6 +15,7 @@
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#include "lib/crypt_ops/crypto_s2k.h"
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#include "lib/crypt_ops/crypto_util.h"
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#include "lib/ctime/di_ops.h"
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#include "lib/intmath/muldiv.h"
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#include "common/util.h"
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#include "trunnel/pwbox.h"
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@ -212,4 +213,3 @@ crypto_unpwbox(uint8_t **out, size_t *outlen_out,
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memwipe(keys, 0, sizeof(keys));
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return rv;
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}
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4
src/lib/intmath/.may_include
Normal file
4
src/lib/intmath/.may_include
Normal file
@ -0,0 +1,4 @@
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orconfig.h
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lib/cc/*.h
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lib/err/*.h
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lib/intmath/*.h
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20
src/lib/intmath/addsub.c
Normal file
20
src/lib/intmath/addsub.c
Normal file
@ -0,0 +1,20 @@
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/* Copyright (c) 2003-2004, Roger Dingledine
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* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
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* Copyright (c) 2007-2018, The Tor Project, Inc. */
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/* See LICENSE for licensing information */
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#include "lib/intmath/addsub.h"
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#include "lib/cc/compat_compiler.h"
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/* Helper: safely add two uint32_t's, capping at UINT32_MAX rather
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* than overflow */
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uint32_t
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tor_add_u32_nowrap(uint32_t a, uint32_t b)
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{
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/* a+b > UINT32_MAX check, without overflow */
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if (PREDICT_UNLIKELY(a > UINT32_MAX - b)) {
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return UINT32_MAX;
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} else {
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return a+b;
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}
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}
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13
src/lib/intmath/addsub.h
Normal file
13
src/lib/intmath/addsub.h
Normal file
@ -0,0 +1,13 @@
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/* Copyright (c) 2003-2004, Roger Dingledine
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* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
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* Copyright (c) 2007-2018, The Tor Project, Inc. */
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/* See LICENSE for licensing information */
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#ifndef TOR_INTMATH_ADDSUB_H
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#define TOR_INTMATH_ADDSUB_H
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#include "lib/cc/torint.h"
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uint32_t tor_add_u32_nowrap(uint32_t a, uint32_t b);
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#endif /* !defined(TOR_INTMATH_MULDIV_H) */
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88
src/lib/intmath/bits.c
Normal file
88
src/lib/intmath/bits.c
Normal file
@ -0,0 +1,88 @@
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/* Copyright (c) 2003-2004, Roger Dingledine
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* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
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* Copyright (c) 2007-2018, The Tor Project, Inc. */
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/* See LICENSE for licensing information */
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#include "lib/intmath/bits.h"
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/** Returns floor(log2(u64)). If u64 is 0, (incorrectly) returns 0. */
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int
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tor_log2(uint64_t u64)
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{
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int r = 0;
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if (u64 >= (U64_LITERAL(1)<<32)) {
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u64 >>= 32;
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r = 32;
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}
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if (u64 >= (U64_LITERAL(1)<<16)) {
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u64 >>= 16;
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r += 16;
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}
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if (u64 >= (U64_LITERAL(1)<<8)) {
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u64 >>= 8;
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r += 8;
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}
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if (u64 >= (U64_LITERAL(1)<<4)) {
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u64 >>= 4;
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r += 4;
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}
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if (u64 >= (U64_LITERAL(1)<<2)) {
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u64 >>= 2;
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r += 2;
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}
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if (u64 >= (U64_LITERAL(1)<<1)) {
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// u64 >>= 1; // not using this any more.
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r += 1;
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}
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return r;
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}
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/** Return the power of 2 in range [1,UINT64_MAX] closest to <b>u64</b>. If
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* there are two powers of 2 equally close, round down. */
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uint64_t
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round_to_power_of_2(uint64_t u64)
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{
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int lg2;
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uint64_t low;
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uint64_t high;
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if (u64 == 0)
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return 1;
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lg2 = tor_log2(u64);
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low = U64_LITERAL(1) << lg2;
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if (lg2 == 63)
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return low;
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high = U64_LITERAL(1) << (lg2+1);
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if (high - u64 < u64 - low)
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return high;
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else
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return low;
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}
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/** Return the number of bits set in <b>v</b>. */
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int
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n_bits_set_u8(uint8_t v)
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{
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static const int nybble_table[] = {
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0, /* 0000 */
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1, /* 0001 */
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1, /* 0010 */
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2, /* 0011 */
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1, /* 0100 */
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2, /* 0101 */
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2, /* 0110 */
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3, /* 0111 */
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1, /* 1000 */
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2, /* 1001 */
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2, /* 1010 */
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3, /* 1011 */
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2, /* 1100 */
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3, /* 1101 */
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3, /* 1110 */
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4, /* 1111 */
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};
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return nybble_table[v & 15] + nybble_table[v>>4];
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}
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16
src/lib/intmath/bits.h
Normal file
16
src/lib/intmath/bits.h
Normal file
@ -0,0 +1,16 @@
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/* Copyright (c) 2003-2004, Roger Dingledine
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* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
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* Copyright (c) 2007-2018, The Tor Project, Inc. */
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/* See LICENSE for licensing information */
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#ifndef TOR_INTMATH_BITS_H
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#define TOR_INTMATH_BITS_H
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#include "lib/cc/torint.h"
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#include "lib/cc/compat_compiler.h"
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int tor_log2(uint64_t u64) ATTR_CONST;
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uint64_t round_to_power_of_2(uint64_t u64);
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||||
int n_bits_set_u8(uint8_t v);
|
||||
|
||||
#endif /* !defined(TOR_INTMATH_BITS_H) */
|
20
src/lib/intmath/cmp.h
Normal file
20
src/lib/intmath/cmp.h
Normal file
@ -0,0 +1,20 @@
|
||||
/* Copyright (c) 2003-2004, Roger Dingledine
|
||||
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
|
||||
* Copyright (c) 2007-2018, The Tor Project, Inc. */
|
||||
/* See LICENSE for licensing information */
|
||||
|
||||
#ifndef TOR_INTMATH_CMP_H
|
||||
#define TOR_INTMATH_CMP_H
|
||||
|
||||
/* Return <b>v</b> if it's between <b>min</b> and <b>max</b>. Otherwise
|
||||
* return <b>min</b> if <b>v</b> is smaller than <b>min</b>, or <b>max</b> if
|
||||
* <b>b</b> is larger than <b>max</b>.
|
||||
*
|
||||
* Requires that <b>min</b> is no more than <b>max</b>. May evaluate any of
|
||||
* its arguments more than once! */
|
||||
#define CLAMP(min,v,max) \
|
||||
( ((v) < (min)) ? (min) : \
|
||||
((v) > (max)) ? (max) : \
|
||||
(v) )
|
||||
|
||||
#endif /* !defined(TOR_INTMATH_CMP_H) */
|
22
src/lib/intmath/include.am
Normal file
22
src/lib/intmath/include.am
Normal file
@ -0,0 +1,22 @@
|
||||
|
||||
noinst_LIBRARIES += src/lib/libtor-intmath.a
|
||||
|
||||
if UNITTESTS_ENABLED
|
||||
noinst_LIBRARIES += src/lib/libtor-intmath-testing.a
|
||||
endif
|
||||
|
||||
src_lib_libtor_intmath_a_SOURCES = \
|
||||
src/lib/intmath/addsub.c \
|
||||
src/lib/intmath/bits.c \
|
||||
src/lib/intmath/muldiv.c
|
||||
|
||||
src_lib_libtor_intmath_testing_a_SOURCES = \
|
||||
$(src_lib_libtor_intmath_a_SOURCES)
|
||||
src_lib_libtor_intmath_testing_a_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS)
|
||||
src_lib_libtor_intmath_testing_a_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
|
||||
|
||||
noinst_HEADERS += \
|
||||
src/lib/intmath/addsub.h \
|
||||
src/lib/intmath/cmp.h \
|
||||
src/lib/intmath/bits.h \
|
||||
src/lib/intmath/muldiv.h
|
75
src/lib/intmath/muldiv.c
Normal file
75
src/lib/intmath/muldiv.c
Normal file
@ -0,0 +1,75 @@
|
||||
/* Copyright (c) 2003-2004, Roger Dingledine
|
||||
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
|
||||
* Copyright (c) 2007-2018, The Tor Project, Inc. */
|
||||
/* See LICENSE for licensing information */
|
||||
|
||||
#include "lib/intmath/muldiv.h"
|
||||
#include "lib/err/torerr.h"
|
||||
|
||||
#include <stdlib.h>
|
||||
|
||||
/** Return the lowest x such that x is at least <b>number</b>, and x modulo
|
||||
* <b>divisor</b> == 0. If no such x can be expressed as an unsigned, return
|
||||
* UINT_MAX. Asserts if divisor is zero. */
|
||||
unsigned
|
||||
round_to_next_multiple_of(unsigned number, unsigned divisor)
|
||||
{
|
||||
raw_assert(divisor > 0);
|
||||
if (UINT_MAX - divisor + 1 < number)
|
||||
return UINT_MAX;
|
||||
number += divisor - 1;
|
||||
number -= number % divisor;
|
||||
return number;
|
||||
}
|
||||
|
||||
/** Return the lowest x such that x is at least <b>number</b>, and x modulo
|
||||
* <b>divisor</b> == 0. If no such x can be expressed as a uint32_t, return
|
||||
* UINT32_MAX. Asserts if divisor is zero. */
|
||||
uint32_t
|
||||
round_uint32_to_next_multiple_of(uint32_t number, uint32_t divisor)
|
||||
{
|
||||
raw_assert(divisor > 0);
|
||||
if (UINT32_MAX - divisor + 1 < number)
|
||||
return UINT32_MAX;
|
||||
|
||||
number += divisor - 1;
|
||||
number -= number % divisor;
|
||||
return number;
|
||||
}
|
||||
|
||||
/** Return the lowest x such that x is at least <b>number</b>, and x modulo
|
||||
* <b>divisor</b> == 0. If no such x can be expressed as a uint64_t, return
|
||||
* UINT64_MAX. Asserts if divisor is zero. */
|
||||
uint64_t
|
||||
round_uint64_to_next_multiple_of(uint64_t number, uint64_t divisor)
|
||||
{
|
||||
raw_assert(divisor > 0);
|
||||
if (UINT64_MAX - divisor + 1 < number)
|
||||
return UINT64_MAX;
|
||||
number += divisor - 1;
|
||||
number -= number % divisor;
|
||||
return number;
|
||||
}
|
||||
|
||||
/* Helper: return greatest common divisor of a,b */
|
||||
static uint64_t
|
||||
gcd64(uint64_t a, uint64_t b)
|
||||
{
|
||||
while (b) {
|
||||
uint64_t t = b;
|
||||
b = a % b;
|
||||
a = t;
|
||||
}
|
||||
return a;
|
||||
}
|
||||
|
||||
/* Given a fraction *<b>numer</b> / *<b>denom</b>, simplify it.
|
||||
* Requires that the denominator is greater than 0. */
|
||||
void
|
||||
simplify_fraction64(uint64_t *numer, uint64_t *denom)
|
||||
{
|
||||
raw_assert(denom);
|
||||
uint64_t gcd = gcd64(*numer, *denom);
|
||||
*numer /= gcd;
|
||||
*denom /= gcd;
|
||||
}
|
22
src/lib/intmath/muldiv.h
Normal file
22
src/lib/intmath/muldiv.h
Normal file
@ -0,0 +1,22 @@
|
||||
/* Copyright (c) 2003-2004, Roger Dingledine
|
||||
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
|
||||
* Copyright (c) 2007-2018, The Tor Project, Inc. */
|
||||
/* See LICENSE for licensing information */
|
||||
|
||||
#ifndef TOR_INTMATH_MULDIV_H
|
||||
#define TOR_INTMATH_MULDIV_H
|
||||
|
||||
#include "lib/cc/torint.h"
|
||||
|
||||
unsigned round_to_next_multiple_of(unsigned number, unsigned divisor);
|
||||
uint32_t round_uint32_to_next_multiple_of(uint32_t number, uint32_t divisor);
|
||||
uint64_t round_uint64_to_next_multiple_of(uint64_t number, uint64_t divisor);
|
||||
|
||||
void simplify_fraction64(uint64_t *numer, uint64_t *denom);
|
||||
|
||||
/* Compute the CEIL of <b>a</b> divided by <b>b</b>, for nonnegative <b>a</b>
|
||||
* and positive <b>b</b>. Works on integer types only. Not defined if a+(b-1)
|
||||
* can overflow. */
|
||||
#define CEIL_DIV(a,b) (((a)+((b)-1))/(b))
|
||||
|
||||
#endif /* !defined(TOR_INTMATH_MULDIV_H) */
|
@ -156,6 +156,7 @@ pub fn main() {
|
||||
cfg.component("tor-malloc");
|
||||
cfg.component("tor-err-testing");
|
||||
cfg.component("or-event-testing");
|
||||
cfg.component("tor-intmath-testing");
|
||||
cfg.component("tor-ctime-testing");
|
||||
cfg.component("curve25519_donna");
|
||||
cfg.component("keccak-tiny");
|
||||
|
Loading…
Reference in New Issue
Block a user