From 87c1f3f912593910b978b51d62f549e4dc32e8fb Mon Sep 17 00:00:00 2001 From: Khem Raj Date: Fri, 9 Jul 2010 11:23:36 -0700 Subject: [PATCH] include/param.h: Dont use ARG_MAX from kernel headers * Use getrlimit for ARG_MAX in sysconf on nptl. * Define NCARGS directly instead of ARG_MAX Signed-off-by: Khem Raj --- include/sys/param.h | 18 ++++++++++++++---- libc/sysdeps/linux/common/bits/local_lim.h | 10 +++++++++- libc/unistd/sysconf.c | 15 ++++++++++++++- 3 files changed, 37 insertions(+), 6 deletions(-) diff --git a/include/sys/param.h b/include/sys/param.h index 0b0424eb9..19c119a2c 100644 --- a/include/sys/param.h +++ b/include/sys/param.h @@ -1,4 +1,4 @@ -/* Copyright (C) 1995,1996,1997,2000,2001,2003 Free Software Foundation, Inc. +/* Copyright (C) 1995-1997,2000,2001,2003,2008 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -19,10 +19,20 @@ #ifndef _SYS_PARAM_H #define _SYS_PARAM_H 1 +#ifndef ARG_MAX +# define __undef_ARG_MAX +#endif + #include #include #include +/* The kernel headers defines ARG_MAX. The value is wrong, though. */ +#ifndef __undef_ARG_MAX +# undef ARG_MAX +# undef __undef_ARG_MAX +#endif + /* BSD names for some values. */ #define NBBY CHAR_BIT @@ -31,12 +41,12 @@ #endif #define MAXSYMLINKS 20 #define CANBSIZ MAX_CANON -#define NCARGS ARG_MAX #define MAXPATHLEN PATH_MAX -/* The following is not really correct but it is a value we used for a +/* The following are not really correct but it is a value we used for a long time and which seems to be usable. People should not use NOFILE - anyway. */ + and NCARGS anyway. */ #define NOFILE 256 +#define NCARGS 131072 #include diff --git a/libc/sysdeps/linux/common/bits/local_lim.h b/libc/sysdeps/linux/common/bits/local_lim.h index 023ebf3d0..a263b5d28 100644 --- a/libc/sysdeps/linux/common/bits/local_lim.h +++ b/libc/sysdeps/linux/common/bits/local_lim.h @@ -1,5 +1,5 @@ /* Minimum guaranteed maximum values for system limits. Linux version. - Copyright (C) 1993-1998,2000,2002,2003,2004 Free Software Foundation, Inc. + Copyright (C) 1993-1998,2000,2002-2004,2008 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -31,6 +31,9 @@ #ifndef OPEN_MAX # define __undef_OPEN_MAX #endif +#ifndef ARG_MAX +# define __undef_ARG_MAX +#endif /* The kernel sources contain a file with all the needed information. */ #include @@ -50,6 +53,11 @@ # undef OPEN_MAX # undef __undef_OPEN_MAX #endif +/* Have to remove ARG_MAX? */ +#ifdef __undef_ARG_MAX +# undef ARG_MAX +# undef __undef_ARG_MAX +#endif /* The number of data keys per process. */ #define _POSIX_THREAD_KEYS_MAX 128 diff --git a/libc/unistd/sysconf.c b/libc/unistd/sysconf.c index b7cb4946f..d118f1b95 100644 --- a/libc/unistd/sysconf.c +++ b/libc/unistd/sysconf.c @@ -36,6 +36,8 @@ #endif #ifdef __UCLIBC_HAS_THREADS_NATIVE__ #include +#include + #endif #ifndef num_present_cpus @@ -81,9 +83,16 @@ #define RETURN_FUNCTION(f) return f; #endif /* _UCLIBC_GENERATE_SYSCONF_ARCH */ +/* Legacy value of ARG_MAX. The macro is now not defined since the + actual value varies based on the stack size. */ +#define legacy_ARG_MAX 131072 + /* Get the value of the system variable NAME. */ long int sysconf(int name) { +#ifdef __UCLIBC_HAS_THREADS_NATIVE__ + struct rlimit rlimit; +#endif switch (name) { default: @@ -91,7 +100,11 @@ long int sysconf(int name) return -1; case _SC_ARG_MAX: -#ifdef ARG_MAX +#ifdef __UCLIBC_HAS_THREADS_NATIVE__ + /* Use getrlimit to get the stack limit. */ + if (getrlimit (RLIMIT_STACK, &rlimit) == 0) + return MAX (legacy_ARG_MAX, rlimit.rlim_cur / 4); +#elif defined ARG_MAX return ARG_MAX; #else RETURN_NEG_1; -- 2.11.0