diff --git a/libc/include/limits.h b/libc/include/limits.h
index 132f1ed..e1f566c 100644
--- a/libc/include/limits.h
+++ b/libc/include/limits.h
@@ -1,3 +1,6 @@
+/*	$OpenBSD: limits.h,v 1.13 2005/12/31 19:29:38 millert Exp $	*/
+/*	$NetBSD: limits.h,v 1.7 1994/10/26 00:56:00 cgd Exp $	*/
+
 /*
  * Copyright (c) 1988 The Regents of the University of California.
  * All rights reserved.
@@ -29,83 +32,108 @@
  *	@(#)limits.h	5.9 (Berkeley) 4/3/91
  */
 
-#pragma once
+#ifndef _LIMITS_H_
+#define _LIMITS_H_
 
 #include <sys/cdefs.h>
 
-/* Defer to the compiler for the built-in C types. */
-#include_next <limits.h>
-
 /* Historically bionic exposed the content of <float.h> from <limits.h> and <sys/limits.h> too. */
 #include <float.h>
 
-/* Many of the POSIX limits come from the kernel. */
 #include <linux/limits.h>
 
-/*
- * bionic always exposed these alternative names,
- * but clang's <limits.h> considers them GNU extensions,
- * and may or may not have defined them.
- */
-#ifndef LONG_LONG_MIN
-/** Non-portable synonym; use LLONG_MIN directly instead. */
-#define LONG_LONG_MIN LLONG_MIN
-#endif
-#ifndef LONG_LONG_MAX
-/** Non-portable synonym; use LLONG_MAX directly instead. */
-#define LONG_LONG_MAX LLONG_MAX
-#endif
-#ifndef ULONG_LONG_MAX
-/** Non-portable synonym; use ULLONG_MAX directly instead. */
-#define ULONG_LONG_MAX ULLONG_MAX
-#endif
+#define PASS_MAX		128	/* _PASSWORD_LEN from <pwd.h> */
 
-/** Maximum number of positional arguments in a printf()/scanf() format string. */
-#define NL_ARGMAX 9
-/** Maximum number of bytes in a $LANG name. */
-#define NL_LANGMAX 14
-/** Irrelevant with Android's <nl_types.h>. */
-#define NL_MSGMAX 32767
-/** Obsolete; removed from POSIX. */
-#define NL_NMAX 1
-/** Irrelevant with Android's <nl_types.h>. */
-#define NL_SETMAX 255
-/** Irrelevant with Android's <nl_types.h>. */
-#define NL_TEXTMAX 255
+#define NL_ARGMAX		9
+#define NL_LANGMAX		14
+#define NL_MSGMAX		32767
+#define NL_NMAX			1
+#define NL_SETMAX		255
+#define NL_TEXTMAX		255
 
-/** Obsolete; removed from POSIX. */
-#define PASS_MAX 128
-/** Obsolete; removed from POSIX. */
-#define TMP_MAX 308915776
+#define TMP_MAX                 308915776
 
-/** Number of bits in a `long` (POSIX). */
-#if __LP64__
-#define LONG_BIT 64
+/* TODO: get all these from the compiler's <limits.h>? */
+
+#define CHAR_BIT 8
+#ifdef __LP64__
+# define LONG_BIT 64
 #else
-#define LONG_BIT 32
+# define LONG_BIT 32
 #endif
-/** Number of bits in a "word" of `int` (POSIX). */
 #define WORD_BIT 32
 
-/** Maximum value of a uid_t. */
-#define UID_MAX UINT_MAX
-/** Maximum value of a gid_t. */
-#define GID_MAX UINT_MAX
-/** Maximum value of a size_t. */
-#define SIZE_T_MAX ULONG_MAX
-/** Maximum value of a ssize_t. */
-#define SSIZE_MAX LONG_MAX
+#define	SCHAR_MAX	0x7f		/* max value for a signed char */
+#define SCHAR_MIN	(-0x7f-1)	/* min value for a signed char */
 
-/** Maximum number of bytes in a multibyte character. */
+#define	UCHAR_MAX	0xffU		/* max value for an unsigned char */
+#ifdef __CHAR_UNSIGNED__
+# define CHAR_MIN	0		/* min value for a char */
+# define CHAR_MAX	0xff		/* max value for a char */
+#else
+# define CHAR_MAX	0x7f
+# define CHAR_MIN	(-0x7f-1)
+#endif
+
+#define	USHRT_MAX	0xffffU		/* max value for an unsigned short */
+#define	SHRT_MAX	0x7fff		/* max value for a short */
+#define SHRT_MIN        (-0x7fff-1)     /* min value for a short */
+
+#define	UINT_MAX	0xffffffffU	/* max value for an unsigned int */
+#define	INT_MAX		0x7fffffff	/* max value for an int */
+#define	INT_MIN		(-0x7fffffff-1)	/* min value for an int */
+
+#ifdef __LP64__
+# define ULONG_MAX	0xffffffffffffffffUL     /* max value for unsigned long */
+# define LONG_MAX	0x7fffffffffffffffL      /* max value for a signed long */
+# define LONG_MIN	(-0x7fffffffffffffffL-1) /* min value for a signed long */
+#else
+# define ULONG_MAX	0xffffffffUL	/* max value for an unsigned long */
+# define LONG_MAX	0x7fffffffL	/* max value for a long */
+# define LONG_MIN	(-0x7fffffffL-1)/* min value for a long */
+#endif
+
+# define ULLONG_MAX	0xffffffffffffffffULL     /* max value for unsigned long long */
+# define LLONG_MAX	0x7fffffffffffffffLL      /* max value for a signed long long */
+# define LLONG_MIN	(-0x7fffffffffffffffLL-1) /* min value for a signed long long */
+
+/* GLibc compatibility definitions.
+   Note that these are defined by GCC's <limits.h>
+   only when __GNU_LIBRARY__ is defined, i.e. when
+   targetting GLibc. */
+#ifndef LONG_LONG_MIN
+#define LONG_LONG_MIN  LLONG_MIN
+#endif
+
+#ifndef LONG_LONG_MAX
+#define LONG_LONG_MAX  LLONG_MAX
+#endif
+
+#ifndef ULONG_LONG_MAX
+#define ULONG_LONG_MAX  ULLONG_MAX
+#endif
+
+#if defined(__USE_BSD) || defined(__BIONIC__) /* Historically bionic exposed these. */
+# define UID_MAX	UINT_MAX	/* max value for a uid_t */
+# define GID_MAX	UINT_MAX	/* max value for a gid_t */
+#if defined(__LP64__)
+#define SIZE_T_MAX ULONG_MAX
+#else
+#define SIZE_T_MAX UINT_MAX
+#endif
+#endif
+
+#if defined(__LP64__)
+#define SSIZE_MAX LONG_MAX
+#else
+#define SSIZE_MAX INT_MAX
+#endif
+
 #define MB_LEN_MAX 4
 
-/** Default process priority. */
 #define NZERO 20
 
-/** Maximum number of struct iovec that can be passed in a single readv()/writev(). */
 #define IOV_MAX 1024
-
-/** Maximum value for a semaphore. */
 #define SEM_VALUE_MAX 0x3fffffff
 
 /** Do not use: prefer getline() or asprintf() rather than hard-coding an arbitrary size. */
@@ -114,17 +142,12 @@
 /* POSIX says these belong in <unistd.h> but BSD has some in <limits.h>. */
 #include <bits/posix_limits.h>
 
-/** Maximum length of a hostname returned by gethostname(). */
 #define HOST_NAME_MAX _POSIX_HOST_NAME_MAX
-
-/** Maximum length of a login name. */
 #define LOGIN_NAME_MAX 256
-
-/** Maximum length of terminal device name. */
 #define TTY_NAME_MAX 32
 
-/** Maximum number of attempts to destroy thread-specific data when a thread exits. */
-#define PTHREAD_DESTRUCTOR_ITERATIONS _POSIX_THREAD_DESTRUCTOR_ITERATIONS
+/* >= _POSIX_THREAD_DESTRUCTOR_ITERATIONS */
+#define PTHREAD_DESTRUCTOR_ITERATIONS 4
 
 /**
  * The number of calls to pthread_key_create() without intervening calls to
@@ -133,5 +156,7 @@
  */
 #define PTHREAD_KEYS_MAX 128
 
-/** bionic has no fixed limit on the number of threads. */
+/** bionic has no specific limit on the number of threads. */
 #undef PTHREAD_THREADS_MAX
+
+#endif /* !_LIMITS_H_ */