From 0e077a7eea286a8efd63460d0ea5d99e44a86b71 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 24 Jul 2008 18:33:44 +0000 Subject: * elf/elf.h: Define AT_EXECFN. * elf/rtld.c [!__ASSUME_AT_EXECFN] (process_envvars): Don't handle LD_ORIGIN_PATH. * elf/dl-sysdep.c (_dl_sysdep_start): Handle AT_EXECFN. * elf/dl-support.c: Define _dl_execfn. Don't define _dl_origin_path if __ASSUME_AT_EXECFN is defined. (_dl_aux_init): Handle AT_EXECFN. * sysdeps/unix/sysv/linux/kernel-features.h: Define __ASSUME_AT_EXECFN for 2.6.27 and up. * sysdeps/generic/ldsodefs.h (rtld_global_ro): Add _dl_execfn. Don't define _dl_origin_path if __ASSUME_AT_EXECFN is defined. * sysdeps/unix/sysv/linux/dl-origin.c (_dl_get_origin): Use _dl_execfn if available and avoid compatibility code if __ASSUME_AT_EXECFN is defined. --- sysdeps/generic/ldsodefs.h | 6 ++++ sysdeps/unix/sysv/linux/dl-origin.c | 53 ++++++++++++++++++++----------- sysdeps/unix/sysv/linux/kernel-features.h | 7 +++- 3 files changed, 47 insertions(+), 19 deletions(-) (limited to 'sysdeps') diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 9d1ebdf615..27c8fb620d 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -38,6 +38,7 @@ #include #include #include +#include __BEGIN_DECLS @@ -592,8 +593,13 @@ struct rtld_global_ro /* Names of shared object for which the RPATH should be ignored. */ EXTERN const char *_dl_inhibit_rpath; +#ifndef __ASSUME_AT_EXECFN /* Location of the binary. */ EXTERN const char *_dl_origin_path; +#endif + + /* If set, points to the file name of the executable. */ + EXTERN const char *_dl_execfn; /* -1 if the dynamic linker should honor library load bias, 0 if not, -2 use the default (honor biases for normal diff --git a/sysdeps/unix/sysv/linux/dl-origin.c b/sysdeps/unix/sysv/linux/dl-origin.c index a7fa53ea1d..5dacec60d9 100644 --- a/sysdeps/unix/sysv/linux/dl-origin.c +++ b/sysdeps/unix/sysv/linux/dl-origin.c @@ -1,5 +1,5 @@ /* Find path of executable. - Copyright (C) 1998, 1999, 2000, 2002, 2004 Free Software Foundation, Inc. + Copyright (C) 1998-2000, 2002, 2004, 2008 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 1998. @@ -35,30 +35,32 @@ const char * _dl_get_origin (void) { +#ifndef __ASSUME_AT_EXECFN char linkval[PATH_MAX]; - char *result; +#endif + char *str; + char *result = (char *) -1l; int len; - INTERNAL_SYSCALL_DECL (err); - len = INTERNAL_SYSCALL (readlink, err, 3, "/proc/self/exe", linkval, - sizeof (linkval)); - if (! INTERNAL_SYSCALL_ERROR_P (len, err) && len > 0 && linkval[0] != '[') + str = GLRO(dl_execfn); +#ifndef __ASSUME_AT_EXECFN + if (str == NULL) { - /* We can use this value. */ - assert (linkval[0] == '/'); - while (len > 1 && linkval[len - 1] != '/') - --len; - result = (char *) malloc (len + 1); - if (result == NULL) - result = (char *) -1; - else if (len == 1) - memcpy (result, "/", 2); - else - *((char *) __mempcpy (result, linkval, len - 1)) = '\0'; + INTERNAL_SYSCALL_DECL (err); + + len = INTERNAL_SYSCALL (readlink, err, 3, "/proc/self/exe", linkval, + sizeof (linkval)); + if (! INTERNAL_SYSCALL_ERROR_P (len, err) + && len > 0 && linkval[0] != '[') + str = linkval; } else +#endif + len = strlen (str); + +#ifndef __ASSUME_AT_EXECFN + if (str == NULL) { - result = (char *) -1; /* We use the environment variable LD_ORIGIN_PATH. If it is set make a copy and strip out trailing slashes. */ if (GLRO(dl_origin_path) != NULL) @@ -76,6 +78,21 @@ _dl_get_origin (void) } } } + else +#endif + { + /* We can use this value. */ + assert (str[0] == '/'); + while (len > 1 && str[len - 1] != '/') + --len; + result = (char *) malloc (len + 1); + if (result == NULL) + result = (char *) -1; + else if (len == 1) + memcpy (result, "/", 2); + else + *((char *) __mempcpy (result, str, len - 1)) = '\0'; + } return result; } diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 01baab0903..5b41429f16 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -1,6 +1,6 @@ /* Set flags signalling availability of kernel features based on given kernel version number. - Copyright (C) 1999-2006, 2007 Free Software Foundation, Inc. + Copyright (C) 1999-2006, 2007, 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 @@ -492,3 +492,8 @@ #if __LINUX_KERNEL_VERSION >= 0x020618 # define __ASSUME_ADJ_OFFSET_SS_READ 1 #endif + +/* Support for AT_EXECFN was added in 2.6.27. */ +#if __LINUX_KERNEL_VERSION >= 0x02061b +# define __ASSUME_AT_EXECFN 1 +#endif -- cgit v1.2.3