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8af197560e
Actually Portable Python is now outperforming the Python binaries
that come bundled with Linux distros, at things like HTTP serving.
You can now have a fully featured Python install in just one .com
file that runs on six operating systems and is about 10mb in size.
With tuning, the tiniest is ~1mb. We've got most of the libraries
working, including pysqlite, and the repl now feels very pleasant.
The things you can't do quite yet are: threads and shared objects
but that can happen in the future, if the community falls in love
with this project and wants to see it developed further. Changes:
- Add siginterrupt()
- Add sqlite3 to Python
- Add issymlink() helper
- Make GetZipCdir() faster
- Add tgamma() and finite()
- Add legacy function lutimes()
- Add readlink() and realpath()
- Use heap allocations when appropriate
- Reorganize Python into two-stage build
- Save Lua / Python shell history to dotfile
- Integrate Python Lib embedding into linkage
- Make isregularfile() and isdirectory() go faster
- Make Python shell auto-completion work perfectly
- Make crash reports work better if changed directory
- Fix Python+NT open() / access() flag overflow error
- Disable Python tests relating to \N{LONG NAME} syntax
- Have Python REPL copyright() show all notice embeddings
The biggest technical challenge at the moment is working around
when Python tries to be too clever about filenames.
207 lines
7.1 KiB
C
207 lines
7.1 KiB
C
/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
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│vi: set et ft=c ts=8 tw=8 fenc=utf-8 :vi│
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╚──────────────────────────────────────────────────────────────────────────────╝
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│ │
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│ Musl Libc │
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│ Copyright © 2005-2014 Rich Felker, et al. │
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│ │
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│ Permission is hereby granted, free of charge, to any person obtaining │
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│ a copy of this software and associated documentation files (the │
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│ "Software"), to deal in the Software without restriction, including │
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│ without limitation the rights to use, copy, modify, merge, publish, │
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│ distribute, sublicense, and/or sell copies of the Software, and to │
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│ permit persons to whom the Software is furnished to do so, subject to │
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│ the following conditions: │
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│ │
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│ The above copyright notice and this permission notice shall be │
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│ included in all copies or substantial portions of the Software. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │
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│ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │
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│ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │
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│ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY │
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│ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, │
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│ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE │
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│ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │
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│ │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/math.h"
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#include "libc/tinymath/feval.internal.h"
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#include "libc/tinymath/kernel.internal.h"
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asm(".ident\t\"\\n\\n\
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Musl libc (MIT License)\\n\
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Copyright 2005-2014 Rich Felker, et. al.\"");
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asm(".include \"libc/disclaimer.inc\"");
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/* clang-format off */
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/*
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"A Precision Approximation of the Gamma Function" - Cornelius Lanczos (1964)
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"Lanczos Implementation of the Gamma Function" - Paul Godfrey (2001)
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"An Analysis of the Lanczos Gamma Approximation" - Glendon Ralph Pugh (2004)
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approximation method:
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(x - 0.5) S(x)
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Gamma(x) = (x + g - 0.5) * ----------------
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exp(x + g - 0.5)
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with
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a1 a2 a3 aN
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S(x) ~= [ a0 + ----- + ----- + ----- + ... + ----- ]
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x + 1 x + 2 x + 3 x + N
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with a0, a1, a2, a3,.. aN constants which depend on g.
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for x < 0 the following reflection formula is used:
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Gamma(x)*Gamma(-x) = -pi/(x sin(pi x))
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most ideas and constants are from boost and python
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*/
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static const double pi = 3.141592653589793238462643383279502884;
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/* sin(pi x) with x > 0x1p-100, if sin(pi*x)==0 the sign is arbitrary */
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static double sinpi(double x)
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{
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int n;
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/* argument reduction: x = |x| mod 2 */
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/* spurious inexact when x is odd int */
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x = x * 0.5;
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x = 2 * (x - floor(x));
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/* reduce x into [-.25,.25] */
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n = 4 * x;
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n = (n+1)/2;
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x -= n * 0.5;
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x *= pi;
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switch (n) {
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default: /* case 4 */
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case 0:
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return __sin(x, 0, 0);
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case 1:
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return __cos(x, 0);
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case 2:
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return __sin(-x, 0, 0);
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case 3:
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return -__cos(x, 0);
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}
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}
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#define N 12
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//static const double g = 6.024680040776729583740234375;
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static const double gmhalf = 5.524680040776729583740234375;
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static const double Snum[N+1] = {
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23531376880.410759688572007674451636754734846804940,
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42919803642.649098768957899047001988850926355848959,
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35711959237.355668049440185451547166705960488635843,
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17921034426.037209699919755754458931112671403265390,
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6039542586.3520280050642916443072979210699388420708,
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1439720407.3117216736632230727949123939715485786772,
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248874557.86205415651146038641322942321632125127801,
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31426415.585400194380614231628318205362874684987640,
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2876370.6289353724412254090516208496135991145378768,
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186056.26539522349504029498971604569928220784236328,
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8071.6720023658162106380029022722506138218516325024,
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210.82427775157934587250973392071336271166969580291,
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2.5066282746310002701649081771338373386264310793408,
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};
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static const double Sden[N+1] = {
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0, 39916800, 120543840, 150917976, 105258076, 45995730, 13339535,
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2637558, 357423, 32670, 1925, 66, 1,
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};
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/* n! for small integer n */
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static const double fact[] = {
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1, 1, 2, 6, 24, 120, 720, 5040.0, 40320.0, 362880.0, 3628800.0, 39916800.0,
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479001600.0, 6227020800.0, 87178291200.0, 1307674368000.0, 20922789888000.0,
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355687428096000.0, 6402373705728000.0, 121645100408832000.0,
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2432902008176640000.0, 51090942171709440000.0, 1124000727777607680000.0,
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};
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/* S(x) rational function for positive x */
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static double S(double x)
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{
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double_t num = 0, den = 0;
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int i;
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/* to avoid overflow handle large x differently */
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if (x < 8)
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for (i = N; i >= 0; i--) {
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num = num * x + Snum[i];
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den = den * x + Sden[i];
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}
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else
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for (i = 0; i <= N; i++) {
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num = num / x + Snum[i];
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den = den / x + Sden[i];
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}
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return num/den;
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}
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double tgamma(double x)
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{
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union {double f; uint64_t i;} u = {x};
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double absx, y;
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double_t dy, z, r;
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uint32_t ix = u.i>>32 & 0x7fffffff;
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int sign = u.i>>63;
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/* special cases */
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if (ix >= 0x7ff00000)
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/* tgamma(nan)=nan, tgamma(inf)=inf, tgamma(-inf)=nan with invalid */
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return x + INFINITY;
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if (ix < (0x3ff-54)<<20)
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/* |x| < 2^-54: tgamma(x) ~ 1/x, +-0 raises div-by-zero */
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return 1/x;
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/* integer arguments */
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/* raise inexact when non-integer */
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if (x == floor(x)) {
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if (sign)
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return 0/0.0;
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if (x <= sizeof fact/sizeof *fact)
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return fact[(int)x - 1];
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}
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/* x >= 172: tgamma(x)=inf with overflow */
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/* x =< -184: tgamma(x)=+-0 with underflow */
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if (ix >= 0x40670000) { /* |x| >= 184 */
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if (sign) {
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fevalf(0x1p-126/x);
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if (floor(x) * 0.5 == floor(x * 0.5))
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return 0;
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return -0.0;
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}
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x *= 0x1p1023;
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return x;
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}
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absx = sign ? -x : x;
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/* handle the error of x + g - 0.5 */
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y = absx + gmhalf;
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if (absx > gmhalf) {
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dy = y - absx;
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dy -= gmhalf;
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} else {
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dy = y - gmhalf;
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dy -= absx;
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}
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z = absx - 0.5;
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r = S(absx) * exp(-y);
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if (x < 0) {
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/* reflection formula for negative x */
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/* sinpi(absx) is not 0, integers are already handled */
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r = -pi / (sinpi(absx) * absx * r);
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dy = -dy;
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z = -z;
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}
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r += dy * (gmhalf+0.5) * r / y;
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z = pow(y, 0.5*z);
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y = r * z * z;
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return y;
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}
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