Make major improvements to redbean

- lua server pages
- lua http library
- http v0.9 support
- request uri parsing
- fork failure recovery
- accelerated redirects
- http pipelining support
- lenient message framing
- html / uri / js escaping
- fix shutdown signal handling

net/http/escapehtml.c

@@ -0,0 +1,81 @@
+/*-*- 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 "libc/x/x.h"
+#include "net/http/escape.h"
+
+/**
+ * Escapes HTML entities.
+ */
+struct EscapeResult EscapeHtml(const char *data, size_t size) {
+  int c;
+  char *p;
+  size_t i;
+  struct EscapeResult r;
+  p = r.data = xmalloc(size * 6 + 1);
+  for (i = 0; i < size; ++i) {
+    switch ((c = data[i])) {
+      case '&':
+        p[0] = '&';
+        p[1] = 'a';
+        p[2] = 'm';
+        p[3] = 'p';
+        p[4] = ';';
+        p += 5;
+        break;
+      case '<':
+        p[0] = '&';
+        p[1] = 'l';
+        p[2] = 't';
+        p[3] = ';';
+        p += 4;
+        break;
+      case '>':
+        p[0] = '&';
+        p[1] = 'g';
+        p[2] = 't';
+        p[3] = ';';
+        p += 4;
+        break;
+      case '"':
+        p[0] = '&';
+        p[1] = 'q';
+        p[2] = 'u';
+        p[3] = 'o';
+        p[4] = 't';
+        p[5] = ';';
+        p += 6;
+        break;
+      case '\'':
+        p[0] = '&';
+        p[1] = '#';
+        p[2] = '3';
+        p[3] = '9';
+        p[4] = ';';
+        p += 5;
+        break;
+      default:
+        *p++ = c;
+        break;
+    }
+  }
+  r.size = p - r.data;
+  r.data = xrealloc(r.data, r.size + 1);
+  r.data[r.size] = '\0';
+  return r;
+}