HardenedBSD/bin/sh/exec.h
Jilles Tjoelker 84fbdd8ca0 sh: Expand assignment-like words specially for export/readonly/local.
Examples:
  export x=~
now expands the tilde
  local y=$1
is now safe, even if $1 contains IFS characters or metacharacters.

For a word to "look like an assignment", it must start with a name followed
by an equals sign, none of which may be quoted.

The special treatment applies when the first word (potentially after
"command") is "export", "readonly" or "local". There may be quoting
characters but no expansions. If "local" is overridden with a function there
is no special treatment ("export" and "readonly" cannot be overridden with a
function).

If things like
  local arr=(1 2 3)
are ever allowed in the future, they cannot call a "local" function. This
would either be a run-time error or it would call the builtin.

This matches Austin Group bug #351, planned for the next issue of POSIX.1.

PR:		bin/166771
2012-07-15 10:19:43 +00:00

78 lines
2.9 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* 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.
*
* @(#)exec.h 8.3 (Berkeley) 6/8/95
* $FreeBSD$
*/
/* values of cmdtype */
#define CMDUNKNOWN -1 /* no entry in table for command */
#define CMDNORMAL 0 /* command is an executable program */
#define CMDBUILTIN 1 /* command is a shell builtin */
#define CMDFUNCTION 2 /* command is a shell function */
/* values for typecmd_impl's third parameter */
enum {
TYPECMD_SMALLV, /* command -v */
TYPECMD_BIGV, /* command -V */
TYPECMD_TYPE /* type */
};
union node;
struct cmdentry {
int cmdtype;
union param {
int index;
struct funcdef *func;
} u;
int special;
};
/* action to find_command() */
#define DO_ERR 0x01 /* prints errors */
#define DO_NOFUNC 0x02 /* don't return shell functions, for command */
extern const char *pathopt; /* set by padvance */
extern int exerrno; /* last exec error */
void shellexec(char **, char **, const char *, int) __dead2;
char *padvance(const char **, const char *);
void find_command(const char *, struct cmdentry *, int, const char *);
int find_builtin(const char *, int *);
void hashcd(void);
void changepath(const char *);
void defun(const char *, union node *);
int unsetfunc(const char *);
int isfunc(const char *);
int typecmd_impl(int, char **, int, const char *);
void clearcmdentry(void);