Get Cosmopolitan into releasable state

A new rollup tool now exists for flattening out the headers in a way
that works better for our purposes than cpp. A lot of the API clutter
has been removed. APIs that aren't a sure thing in terms of general
recommendation are now marked internal.

There's now a smoke test for the amalgamation archive and gigantic
header file. So we can now guarantee you can use this project on the
easiest difficulty setting without the gigantic repository.

A website is being created, which is currently a work in progress:
https://justine.storage.googleapis.com/cosmopolitan/index.html

tool/build/rollup.c

@@ -0,0 +1,149 @@
+/*-*- 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 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ This program is free software; you can redistribute it and/or modify         │
+│ it under the terms of the GNU General Public License as published by         │
+│ the Free Software Foundation; version 2 of the License.                      │
+│                                                                              │
+│ This program 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             │
+│ General Public License for more details.                                     │
+│                                                                              │
+│ You should have received a copy of the GNU General Public License            │
+│ along with this program; if not, write to the Free Software                  │
+│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
+│ 02110-1301 USA                                                               │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/alg/arraylist2.internal.h"
+#include "libc/calls/calls.h"
+#include "libc/calls/struct/stat.h"
+#include "libc/conv/itoa.h"
+#include "libc/log/check.h"
+#include "libc/log/log.h"
+#include "libc/mem/mem.h"
+#include "libc/runtime/runtime.h"
+#include "libc/str/str.h"
+#include "libc/sysv/consts/map.h"
+#include "libc/sysv/consts/o.h"
+#include "libc/sysv/consts/prot.h"
+
+#define LOOKINGAT(p, pe, s) LookingAt(p, pe, s, strlen(s))
+#define APPENDSTR(s)        AppendData(s, strlen(s))
+
+struct Output {
+  size_t i, n;
+  const char *p;
+};
+
+struct Visited {
+  size_t i, n;
+  const char **p;
+};
+
+static struct stat st;
+static struct Output output;
+static struct Visited visited;
+
+static void Visit(const char *);
+
+static bool HasVisited(const char *path) {
+  int i;
+  for (i = 0; i < visited.i; ++i) {
+    if (strcmp(path, visited.p[i]) == 0) {
+      return true;
+    }
+  }
+  return false;
+}
+
+static void AppendData(const char *s, size_t n) {
+  CONCAT(&output.p, &output.i, &output.n, s, n);
+}
+
+static void AppendInt(long x) {
+  char ibuf[21];
+  AppendData(ibuf, int64toarray_radix10(x, ibuf));
+}
+
+static bool LookingAt(const char *p, const char *pe, const char *s, size_t n) {
+  return pe - p >= n && memcmp(p, s, n) == 0;
+}
+
+static void Process(const char *p, const char *pe, const char *path,
+                    bool isheader) {
+  int level;
+  bool noformat;
+  const char *p2, *dq, *name;
+  for (noformat = level = 0; p < pe; p = p2) {
+    p2 = memchr(p, '\n', pe - p);
+    p2 = p2 ? p2 + 1 : pe;
+    if (LOOKINGAT(p, pe, "#if")) {
+      if (isheader && !level++) continue;
+    }
+    if (LOOKINGAT(p, pe, "#endif")) {
+      if (isheader && !--level) continue;
+    }
+    if (LOOKINGAT(p, pe, "/* clang-format off */")) {
+      noformat = true;
+    } else if (LOOKINGAT(p, pe, "/* clang-format on */")) {
+      noformat = false;
+    }
+    if (LOOKINGAT(p, pe, "#include \"")) {
+      name = p + strlen("#include \"");
+      dq = memchr(name, '"', pe - name);
+      if (dq) {
+        Visit(strndup(name, dq - name));
+        continue;
+      }
+    }
+    AppendData(p, p2 - p);
+  }
+  if (noformat) {
+    APPENDSTR("/* clang-format on */\n");
+  }
+}
+
+static void Visit(const char *path) {
+  int fd;
+  char *map;
+  bool isheader;
+  if (!endswith(path, ".h") && !endswith(path, ".inc")) return;
+  if (endswith(path, ".internal.h")) return;
+  if (endswith(path, "/internal.h")) return;
+  if (endswith(path, ".internal.inc")) return;
+  if (endswith(path, "/internal.inc")) return;
+  isheader = endswith(path, ".h");
+  if (isheader && HasVisited(path)) return;
+  APPENDSTR("\n\f\n/*!BEGIN ");
+  APPENDSTR(path);
+  APPENDSTR(" */\n\n");
+  APPEND(&visited.p, &visited.i, &visited.n, &path);
+  CHECK_NE(-1, (fd = open(path, O_RDONLY)));
+  CHECK_NE(-1, fstat(fd, &st));
+  if (st.st_size) {
+    CHECK_NE(MAP_FAILED,
+             (map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0)));
+    Process(map, map + st.st_size, path, isheader);
+    LOGIFNEG1(munmap(map, st.st_size));
+  }
+  LOGIFNEG1(close(fd));
+}
+
+int main(int argc, char *argv[]) {
+  int i;
+  APPENDSTR("#ifndef COSMOPOLITAN_H_\n");
+  APPENDSTR("#define COSMOPOLITAN_H_\n");
+  APPENDSTR("#define IMAGE_BASE_VIRTUAL ");
+  AppendInt(IMAGE_BASE_VIRTUAL);
+  APPENDSTR("\n");
+  for (i = 1; i < argc; ++i) {
+    Visit(argv[i]);
+  }
+  APPENDSTR("\n");
+  APPENDSTR("#endif /* COSMOPOLITAN_H_ */\n");
+  CHECK_EQ(output.i, write(1, output.p, output.i));
+  return 0;
+}