Make ZipOS and Qemu work better

This change improves the dirstream library in a lot of respects, especially for /zip/... files. Also turn off MAP_STACK on Aarch64 because Qemu seems to implement it differently than Linux and it's probably responsible for a lot of mysterious crashes.
2025-05-22 21:32:31 +00:00 · 2023-08-15 18:24:53 -07:00 · 2023-08-15 18:24:53 -07:00 · 110559ce6a
commit 110559ce6a
parent 4658ae539f
48 changed files with 748 additions and 500 deletions
--- a/libc/runtime/zipos-normpath.c
+++ b/libc/runtime/zipos-normpath.c
@ -0,0 +1,80 @@
+/*-*- 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                              │
+│                                                                              │
+│ 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/runtime/zipos.internal.h"
+
+static size_t __zipos_trimpath(char *s, int *isabs) {
+  char *p = s, *q = s;
+  for (; *q; ++q) {
+    if (*q == '/') {
+      while (q[1] == '/') ++q;
+      if (q[1] == '.' && (q[2] == '/' || q[2] == '\0')) {
+        ++q;
+      } else {
+        *p++ = '/';
+      }
+    } else {
+      *p++ = *q;
+    }
+  }
+  if (s < p && p[-1] == '.' && p[-2] == '.' && (p - 2 == s || p[-3] == '/')) {
+    *p++ = '/';
+  }
+  *p = '\0';
+  if (isabs) {
+    *isabs = *s == '/';
+  }
+  return p - s;
+}
+
+size_t __zipos_normpath(char *s) {
+  int isabs;
+  char *p = s, *q = s;
+  __zipos_trimpath(s, &isabs);
+  if (!*s) return 0;
+  for (; *q != '\0'; ++q) {
+    if (q[0] == '/' && q[1] == '.' && q[2] == '.' &&
+        (q[3] == '/' || q[3] == '\0')) {
+      char *ep = p;
+      while (s < ep && *--ep != '/') donothing;
+      if (ep != p &&
+          (p[-1] != '.' || p[-2] != '.' || (s < p - 3 && p[-3] != '/'))) {
+        p = ep;
+        q += 2;
+        continue;
+      } else if (ep == s && isabs) {
+        q += 2;
+        continue;
+      }
+    }
+    if (q[0] != '/' || p != s || isabs) {
+      *p++ = *q;
+    }
+  }
+  if (p == s) {
+    *p++ = isabs ? '/' : '.';
+  }
+  if (p == s + 1 && s[0] == '.') {
+    *p++ = '/';
+  }
+  while (p - s > 1 && p[-1] == '/') {
+    --p;
+  }
+  *p = '\0';
+  return p - s;
+}