1 /* 2 * Copyright (c) 1988 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)limits.h 5.9 (Berkeley) 4/3/91 30 */ 31 32 #pragma once 33 34 /** 35 * @file limits.h 36 * @brief Constants relating to implementation limits. 37 * 38 * This file is included via `#include_next` from the clang header of the same 39 * name that provides all the limits that the compiler is responsible for, 40 * primarily those relating to integer types defined by the C standard. 41 * This file defines the additional limits defined by POSIX. 42 */ 43 44 /* 45 * The Android build system has bionic _before_ the clang headers, 46 * so although the claim above that clang does an `#include_next` 47 * of this file is true for the NDK, it's not true for the OS, 48 * and we need to paper over that difference here until/unless 49 * the OS build changes. 50 */ 51 #if __has_include_next(<limits.h>) 52 #include_next <limits.h> 53 #endif 54 55 #include <sys/cdefs.h> 56 57 /* Historically bionic exposed the content of <float.h> from <limits.h> and <sys/limits.h> too. */ 58 #include <float.h> 59 60 /* Many of the POSIX limits come from the kernel. */ 61 #include <linux/limits.h> 62 63 /** Maximum number of positional arguments in a printf()/scanf() format string. */ 64 #define NL_ARGMAX 9 65 /** Maximum number of bytes in a $LANG name. */ 66 #define NL_LANGMAX 14 67 /** Irrelevant with Android's <nl_types.h>. */ 68 #define NL_MSGMAX 32767 69 /** Obsolete; removed from POSIX. */ 70 #define NL_NMAX 1 71 /** Irrelevant with Android's <nl_types.h>. */ 72 #define NL_SETMAX 255 73 /** Irrelevant with Android's <nl_types.h>. */ 74 #define NL_TEXTMAX 255 75 76 /** Obsolete; removed from POSIX. */ 77 #define PASS_MAX 128 78 /** Obsolete; removed from POSIX. */ 79 #define TMP_MAX 308915776 80 81 /** Number of bits in a `long` (POSIX). */ 82 #if __LP64__ 83 #define LONG_BIT 64 84 #else 85 #define LONG_BIT 32 86 #endif 87 /** Number of bits in a "word" of `int` (POSIX). */ 88 #define WORD_BIT 32 89 90 /** Maximum value of a uid_t. */ 91 #define UID_MAX UINT_MAX 92 /** Maximum value of a gid_t. */ 93 #define GID_MAX UINT_MAX 94 /** Maximum value of a size_t. */ 95 #define SIZE_T_MAX ULONG_MAX 96 /** Maximum value of a ssize_t. */ 97 #define SSIZE_MAX LONG_MAX 98 99 /** 100 * POSIX 2024's name for NSIG. 101 * See the NSIG documentation for an explanation and warnings. 102 */ 103 #define NSIG_MAX 65 104 105 /** Maximum number of bytes in a multibyte character. */ 106 #define MB_LEN_MAX 4 107 108 /** Default process priority. */ 109 #define NZERO 20 110 111 /** Maximum number of struct iovec that can be passed in a single readv()/writev(). */ 112 #define IOV_MAX 1024 113 114 /** Maximum value for a semaphore. */ 115 #define SEM_VALUE_MAX 0x3fffffff 116 117 /** Do not use: prefer getline() or asprintf() rather than hard-coding an arbitrary size. */ 118 #define LINE_MAX _POSIX2_LINE_MAX 119 120 /* POSIX says these belong in <unistd.h> but BSD has some in <limits.h>. */ 121 #include <bits/posix_limits.h> 122 123 /** Maximum length of a hostname returned by gethostname(). */ 124 #define HOST_NAME_MAX _POSIX_HOST_NAME_MAX 125 126 /** Maximum length of a login name. */ 127 #define LOGIN_NAME_MAX 256 128 129 /** Maximum length of terminal device name. */ 130 #define TTY_NAME_MAX 32 131 132 /** Maximum number of attempts to destroy thread-specific data when a thread exits. */ 133 #define PTHREAD_DESTRUCTOR_ITERATIONS _POSIX_THREAD_DESTRUCTOR_ITERATIONS 134 135 /** 136 * The number of calls to pthread_key_create() without intervening calls to 137 * pthread_key_delete() that are guaranteed to succeed. See pthread_key_create() 138 * for more details and ways to avoid hitting this limit. 139 */ 140 #define PTHREAD_KEYS_MAX 128 141 142 /** bionic has no fixed limit on the number of threads. */ 143 #undef PTHREAD_THREADS_MAX 144