d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add function getlocalbase() to libutil.

Browse Source 
This function returns the path to the local software base directory, by
default "/usr/local" (or the value of _PATH_LOCALBASE in include/paths.h
when building the world).

The value returned can be overridden by 2 methods:

- the LOCALBASE environment variable (ignored by SUID programs)
- else a non-default user.localbase sysctl value

Reviewed by:	hps (earlier version)
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D27236
This commit is contained in:
Stefan Eßer 2020-11-18 19:44:30 +00:00
parent ed0d16b017
commit 30d21d2795
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=367813
4 changed files with 178 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
lib/libutil/Makefile
View File

@ -12,7 +12,8 @@ PACKAGE= runtime
LIB= util
SHLIB_MAJOR= 9
SRCS= _secure_path.c auth.c expand_number.c flopen.c fparseln.c gr_util.c \
SRCS= _secure_path.c auth.c expand_number.c flopen.c fparseln.c \
getlocalbase.c gr_util.c \
hexdump.c humanize_number.c kinfo_getfile.c \
kinfo_getallproc.c kinfo_getproc.c kinfo_getvmmap.c \
kinfo_getvmobject.c kld.c \
@ -30,7 +31,7 @@ CFLAGS+= -DINET6
CFLAGS+= -I${.CURDIR} -I${SRCTOP}/lib/libc/gen/
MAN+= expand_number.3 flopen.3 fparseln.3 hexdump.3 \
MAN+= expand_number.3 flopen.3 fparseln.3 getlocalbase.3 hexdump.3 \
humanize_number.3 kinfo_getallproc.3 kinfo_getfile.3 \
kinfo_getproc.3 kinfo_getvmmap.3 kinfo_getvmobject.3 kld.3 \
login_auth.3 login_cap.3 \

99
lib/libutil/getlocalbase.3 Normal file
View File

@ -0,0 +1,99 @@
.\"
.\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD
.\"
.\" Copyright 2020 Scott Long
.\" Copyright 2020 Stefan Eßer
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd November 18, 2020
.Dt GETLOCALBASE 3
.Os
.Sh NAME
.Nm getlocalbase
.Nd "return the path to the local software directory"
.Sh LIBRARY
.Lb libutil
.Sh SYNOPSIS
.In libutil.h
.Ft const char*
.Fn getlocalbase "void"
.Sh DESCRIPTION
The
.Fn getlocalbase
function returns the path to the local software base directory.
Normally this is the
.Pa /usr/local
directory.
First the
.Ev LOCALBASE
environment variable is checked.
If that does not exist then the
.Va user.localbase
sysctl is checked.
If that also does not exist then the value of the
.Dv _PATH_LOCALBASE
compile-time variable is used.
If that is undefined then the default of
.Pa /usr/local
is used.
.Pp
The value returned by the
.Fn getlocalbase
function shall not be modified.
.Sh IMPLEMENTATION NOTES
Calls to
.Fn getlocalbase
will perform a setugid check on the running binary before checking the
environment.
.Sh RETURN VALUES
The
.Fn getlocalbase
function always succeeds and returns a pointer to a string, whose length
may exceed MAXPATHLEN if it has been derived from the environment variable
LOCALBASE.
No length checks are performed on the result.
.Sh ENVIRONMENT
The
.Fn getlocalbase
library function retrieves the
.Ev LOCALBASE
environment variable.
.Sh ERRORS
The
.Fn getlocalbase
function always succeeds.
.Sh SEE ALSO
.Xr env 1 ,
.Xr src.conf 5 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
library function first appeared in
.Fx 13.0 .
.Sh AUTHORS
This
manual page was written by
.An Scott Long Aq Mt scottl@FreeBSD.org and Stefan Eßer Aq Mt se@FreeBSD.org .

74
lib/libutil/getlocalbase.c Normal file
View File

@ -0,0 +1,74 @@
/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright 2020 Stefan Eßer <se@freebsd.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/limits.h>
#include <stdlib.h>
#include <paths.h>
#include <libutil.h>
#include <unistd.h>
#ifndef _PATH_LOCALBASE
#define _PATH_LOCALBASE "/usr/local"
#endif
const char *
getlocalbase(void)
{
static const int localbase_oid[2] = {CTL_USER, USER_LOCALBASE};
char *tmppath;
size_t tmplen;
static const char *localbase = NULL;
if (issetugid() == 0) {
tmppath = getenv("LOCALBASE");
if (tmppath != NULL && tmppath[0] != '\0')
return (tmppath);
}
if (sysctl(localbase_oid, 2, NULL, &tmplen, NULL, 0) == 0 &&
(tmppath = malloc(tmplen)) != NULL &&
sysctl(localbase_oid, 2, tmppath, &tmplen, NULL, 0) == 0) {
/*
* Check for some other thread already having
* set localbase - this should use atomic ops.
* The amount of memory allocated above may leak,
* if a parallel update in another thread is not
* detected and the non-NULL pointer is overwritten.
*/
if (tmppath[0] != '\0' &&
(volatile const char*)localbase == NULL)
localbase = tmppath;
else
free((void*)tmppath);
return (localbase);
}
return (_PATH_LOCALBASE);
}

2
lib/libutil/libutil.h
View File

@ -98,6 +98,8 @@ int flopen(const char *_path, int _flags, ...);
int flopenat(int _dirfd, const char *_path, int _flags, ...);
int forkpty(int *_amaster, char *_name,
struct termios *_termp, struct winsize *_winp);
const char *
getlocalbase(void);
void hexdump(const void *_ptr, int _length, const char *_hdr, int _flags);
int humanize_number(char *_buf, size_t _len, int64_t _number,
const char *_suffix, int _scale, int _flags);