Improve Libc by making Python work even better

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.

third_party/python/Python/ceval.c

@@ -228,8 +228,6 @@ static int pending_async_exc = 0;
 
 #ifdef WITH_THREAD
 
-#ifdef HAVE_ERRNO_H
-#endif
 #include "third_party/python/Include/pythread.h"
 
 static PyThread_type_lock pending_lock = 0; /* for pending calls */

third_party/python/Python/frozen.c

@@ -33,7 +33,7 @@ static unsigned char M___hello__[] = {
 
 #define SIZE (int)sizeof(M___hello__)
 
-static const struct _frozen _PyImport_FrozenModules[] = {
+const struct _frozen _PyImport_FrozenModules[] = {
     /* importlib */
     {"_frozen_importlib", _Py_M__importlib, (int)sizeof(_Py_M__importlib)},
     {"_frozen_importlib_external", _Py_M__importlib_external,
@@ -45,8 +45,3 @@ static const struct _frozen _PyImport_FrozenModules[] = {
     {"__phello__.spam", M___hello__, SIZE},
     {0, 0, 0} /* sentinel */
 };
-
-/* Embedding apps may change this pointer to point to their favorite
-   collection of frozen modules: */
-
-const struct _frozen *PyImport_FrozenModules = _PyImport_FrozenModules;

third_party/python/Python/frozenmodules.c

@@ -0,0 +1,22 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "third_party/python/Include/import.h"
+
+static const struct _frozen _PyImport_FrozenModules_Empty[1];
+const struct _frozen *PyImport_FrozenModules = _PyImport_FrozenModules_Empty;

third_party/python/Python/getcopyright.c

@@ -4,27 +4,37 @@
 │ Python 3                                                                     │
 │ https://docs.python.org/3/license.html                                       │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/bits/bits.h"
+#include "libc/bits/weaken.h"
+#include "libc/stdio/append.internal.h"
+#include "libc/str/str.h"
 #include "third_party/python/Include/pylifecycle.h"
 /* clang-format off */
 
-/* Return the copyright string.  This is updated manually. */
+asm(".ident\t\"\\n\\n\
+Python 3.6 (https://docs.python.org/3/license.html)\\n\
+Copyright (c) 2001-2021 Python Software Foundation.\\n\
+All Rights Reserved.\\n\
+Copyright (c) 2000 BeOpen.com.\\n\
+All Rights Reserved.\\n\
+Copyright (c) 1995-2001 Corporation for National Research Initiatives.\\n\
+All Rights Reserved.\\n\
+Copyright (c) 1991-1995 Stichting Mathematisch Centrum, Amsterdam.\\n\
+All Rights Reserved.\"");
 
-static const char cprt[] =
-"\
-Copyright (c) 2001-2021 Python Software Foundation.\n\
-All Rights Reserved.\n\
-\n\
-Copyright (c) 2000 BeOpen.com.\n\
-All Rights Reserved.\n\
-\n\
-Copyright (c) 1995-2001 Corporation for National Research Initiatives.\n\
-All Rights Reserved.\n\
-\n\
-Copyright (c) 1991-1995 Stichting Mathematisch Centrum, Amsterdam.\n\
-All Rights Reserved.";
+extern const char kLegalNotices[];
 
 const char *
 Py_GetCopyright(void)
 {
-    return cprt;
+    const char *p;
+    static bool once;
+    static char *res;
+    if (cmpxchg(&once, 0, 1)) {
+        appends(&res, "");
+        for (p = *weaken(kLegalNotices); *p; p += strlen(p) + 1) {
+            appends(&res, p);
+        }
+    }
+    return res;
 }

third_party/python/Python/inittab.c

@@ -0,0 +1,22 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "third_party/python/Include/import.h"
+
+static struct _inittab _PyImport_Inittab_Empty[1];
+struct _inittab *PyImport_Inittab = _PyImport_Inittab_Empty;

third_party/python/Python/marshal.c

@@ -8,6 +8,8 @@
 #include "dsp/mpeg/video.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/weirdtypes.h"
+#include "libc/mem/mem.h"
+#include "libc/runtime/gc.internal.h"
 #include "third_party/python/Include/abstract.h"
 #include "third_party/python/Include/boolobject.h"
 #include "third_party/python/Include/code.h"
@@ -648,12 +650,12 @@ PyMarshal_WriteLongToFile(long x, FILE *fp, int version)
 void
 PyMarshal_WriteObjectToFile(PyObject *x, FILE *fp, int version)
 {
-    char buf[BUFSIZ];
     WFILE wf;
+    char *buf = gc(malloc(BUFSIZ));
     bzero(&wf, sizeof(wf));
     wf.fp = fp;
     wf.ptr = wf.buf = buf;
-    wf.end = wf.ptr + sizeof(buf);
+    wf.end = wf.ptr + BUFSIZ;
     wf.error = WFERR_OK;
     wf.version = version;
     if (w_init_refs(&wf, version))

third_party/python/Python/opcode_targets.inc

@@ -6,7 +6,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 /* clang-format off */
 
-static void *opcode_targets[256] = {
+static void *const opcode_targets[256] = {
     &&_unknown_opcode,
     &&TARGET_POP_TOP,
     &&TARGET_ROT_TWO,

third_party/python/Python/sysmodule.c

@@ -6,6 +6,8 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
 #include "libc/dce.h"
+#include "libc/mem/mem.h"
+#include "libc/runtime/gc.internal.h"
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/stdio.h"
 #include "libc/sysv/consts/exit.h"
@@ -2175,14 +2177,14 @@ sys_update_path(int argc, wchar_t **argv)
     PyObject *a;
     PyObject *path;
 #ifdef HAVE_READLINK
-    wchar_t link[MAXPATHLEN+1];
-    wchar_t argv0copy[2*MAXPATHLEN+1];
+    wchar_t *link = gc(calloc(MAXPATHLEN+1, sizeof(wchar_t)));
+    wchar_t *argv0copy = gc(calloc(2*MAXPATHLEN+1, sizeof(wchar_t)));
     int nr = 0;
 #endif
 #if defined(HAVE_REALPATH)
-    wchar_t fullpath[MAXPATHLEN];
+    wchar_t *fullpath = gc(calloc(MAXPATHLEN, sizeof(wchar_t)));
 #elif defined(MS_WINDOWS)
-    wchar_t fullpath[MAX_PATH];
+    wchar_t *fullpath = gc(calloc(MAX_PATH, sizeof(wchar_t)));
 #endif
 
     path = _PySys_GetObjectId(&PyId_path);
@@ -2224,10 +2226,7 @@ sys_update_path(int argc, wchar_t **argv)
 #if defined(MS_WINDOWS)
         /* Replace the first element in argv with the full path. */
         wchar_t *ptemp;
-        if (GetFullPathNameW(argv0,
-                           Py_ARRAY_LENGTH(fullpath),
-                           fullpath,
-                           &ptemp)) {
+        if (GetFullPathNameW(argv0, MAX_PATH, fullpath, &ptemp)) {
             argv0 = fullpath;
         }
 #endif
@@ -2245,7 +2244,7 @@ sys_update_path(int argc, wchar_t **argv)
 #else /* All other filename syntaxes */
     if (_HAVE_SCRIPT_ARGUMENT(argc, argv)) {
 #if defined(HAVE_REALPATH)
-        if (_Py_wrealpath(argv0, fullpath, Py_ARRAY_LENGTH(fullpath))) {
+        if (_Py_wrealpath(argv0, fullpath, MAXPATHLEN)) {
             argv0 = fullpath;
         }
 #endif