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Diffstat (limited to 'libntp/vint64ops.c')
| -rw-r--r-- | libntp/vint64ops.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/libntp/vint64ops.c b/libntp/vint64ops.c new file mode 100644 index 0000000..5adbebb --- /dev/null +++ b/libntp/vint64ops.c @@ -0,0 +1,284 @@ +/* + * vint64ops.c - operations on 'vint64' values + * + * Written by Juergen Perlinger (perlinger@ntp.org) for the NTP project. + * The contents of 'html/copyright.html' apply. + * ---------------------------------------------------------------------- + * This is an attempt to get the vint64 calculations stuff centralised. + */ + +#include <config.h> +#include <stdlib.h> +#include <ctype.h> +#include <string.h> +#include <errno.h> + +#include "ntp_types.h" +#include "ntp_fp.h" +#include "vint64ops.h" + +/* --------------------------------------------------------------------- + * GCC is rather sticky with its 'const' attribute. We have to do it more + * explicit than with a cast if we want to get rid of a CONST qualifier. + * Greetings from the PASCAL world, where casting was only possible via + * untagged unions... + */ +static inline void* +noconst( + const void* ptr + ) +{ + union { + const void * cp; + void * vp; + } tmp; + tmp.cp = ptr; + return tmp.vp; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +strtouv64( + const char * begp, + char ** endp, + int base + ) +{ + vint64 res; + u_char digit; + int sig, num; + const u_char *src; + + num = sig = 0; + src = (const u_char*)begp; + while (isspace(*src)) + src++; + + if (*src == '-') { + src++; + sig = 1; + } else if (*src == '+') { + src++; + } + + if (base == 0) { + base = 10; + if (*src == '0') { + base = 8; + if (toupper(*++src) == 'X') { + src++; + base = 16; + } + } + } else if (base == 16) { /* remove optional leading '0x' or '0X' */ + if (src[0] == '0' && toupper(src[1]) == 'X') + src += 2; + } else if (base <= 2 || base > 36) { + memset(&res, 0xFF, sizeof(res)); + errno = ERANGE; + return res; + } + + memset(&res, 0, sizeof(res)); + while (*src) { + if (isdigit(*src)) + digit = *src - '0'; + else if (isupper(*src)) + digit = *src - 'A' + 10; + else if (islower(*src)) + digit = *src - 'a' + 10; + else + break; + if (digit >= base) + break; + num = 1; +#if defined(HAVE_INT64) + res.Q_s = res.Q_s * base + digit; +#else + /* res *= base, using 16x16->32 bit + * multiplication. Slow but portable. + */ + { + uint32_t accu; + accu = (uint32_t)res.W_s.ll * base; + res.W_s.ll = (uint16_t)accu; + accu = (accu >> 16) + + (uint32_t)res.W_s.lh * base; + res.W_s.lh = (uint16_t)accu; + /* the upper bits can be done in one step: */ + res.D_s.hi = res.D_s.hi * base + (accu >> 16); + } + M_ADD(res.D_s.hi, res.D_s.lo, 0, digit); +#endif + src++; + } + if (!num) + errno = EINVAL; + if (endp) + *endp = (char*)noconst(src); + if (sig) + M_NEG(res.D_s.hi, res.D_s.lo); + return res; +} + +/* -------------------------------------------------------------------------*/ + +int +icmpv64( + const vint64 * lhs, + const vint64 * rhs + ) +{ + int res; + +#if defined(HAVE_INT64) + res = (lhs->q_s > rhs->q_s) + - (lhs->q_s < rhs->q_s); +#else + res = (lhs->d_s.hi > rhs->d_s.hi) + - (lhs->d_s.hi < rhs->d_s.hi); + if ( ! res ) + res = (lhs->D_s.lo > rhs->D_s.lo) + - (lhs->D_s.lo < rhs->D_s.lo); +#endif + + return res; +} + +/* -------------------------------------------------------------------------*/ + +int +ucmpv64( + const vint64 * lhs, + const vint64 * rhs + ) +{ + int res; + +#if defined(HAVE_INT64) + res = (lhs->Q_s > rhs->Q_s) + - (lhs->Q_s < rhs->Q_s); +#else + res = (lhs->D_s.hi > rhs->D_s.hi) + - (lhs->D_s.hi < rhs->D_s.hi); + if ( ! res ) + res = (lhs->D_s.lo > rhs->D_s.lo) + - (lhs->D_s.lo < rhs->D_s.lo); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +addv64( + const vint64 *lhs, + const vint64 *rhs + ) +{ + vint64 res; + +#if defined(HAVE_INT64) + res.Q_s = lhs->Q_s + rhs->Q_s; +#else + res = *lhs; + M_ADD(res.D_s.hi, res.D_s.lo, rhs->D_s.hi, rhs->D_s.lo); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +subv64( + const vint64 *lhs, + const vint64 *rhs + ) +{ + vint64 res; + +#if defined(HAVE_INT64) + res.Q_s = lhs->Q_s - rhs->Q_s; +#else + res = *lhs; + M_SUB(res.D_s.hi, res.D_s.lo, rhs->D_s.hi, rhs->D_s.lo); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +addv64i32( + const vint64 * lhs, + int32_t rhs + ) +{ + vint64 res; + + res = *lhs; +#if defined(HAVE_INT64) + res.q_s += rhs; +#else + M_ADD(res.D_s.hi, res.D_s.lo, -(rhs < 0), rhs); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +subv64i32( + const vint64 * lhs, + int32_t rhs + ) +{ + vint64 res; + + res = *lhs; +#if defined(HAVE_INT64) + res.q_s -= rhs; +#else + M_SUB(res.D_s.hi, res.D_s.lo, -(rhs < 0), rhs); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +addv64u32( + const vint64 * lhs, + uint32_t rhs + ) +{ + vint64 res; + + res = *lhs; +#if defined(HAVE_INT64) + res.Q_s += rhs; +#else + M_ADD(res.D_s.hi, res.D_s.lo, 0, rhs); +#endif + return res; +} + +/* -------------------------------------------------------------------------*/ + +vint64 +subv64u32( + const vint64 * lhs, + uint32_t rhs + ) +{ + vint64 res; + + res = *lhs; +#if defined(HAVE_INT64) + res.Q_s -= rhs; +#else + M_SUB(res.D_s.hi, res.D_s.lo, 0, rhs); +#endif + return res; +} |