History log of /freebsd-current/bin/sh/expand.h
Revision Date Author Comments
# 90aea514 23-Nov-2023 Warner Losh <imp@FreeBSD.org>

bin: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix


# 42b38843 16-Aug-2023 Warner Losh <imp@FreeBSD.org>

Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/


# fbbd9655 28-Feb-2017 Warner Losh <imp@FreeBSD.org>

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96


# 0e39c931 31-Dec-2015 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Perform pathname generation during the first expansion phases.

This avoids the need to add and remove CTLESC bytes if pathname generation
will not be performed (set -f).

Side effect: the order of operations is slightly different: pathname
generation in ${$+* $(CMD)} will not see filesystem changes from CMD.


# 046bfe52 01-Nov-2015 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Avoid copying argv for simple commands.

Add dummy entries before and after so arglist's array is directly usable as
argv.


# 8ef0ae8a 11-Oct-2015 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Make struct arglist an array instead of a linked list.

This simplifies the code (e.g. allowing use of qsort(3) instead of a
hand-rolled mergesort) and should have better cache properties.

The waste of unused args arrays after resizes is approximately the same as
the savings from getting rid of the next pointers.

At the same time, remove a piece of global state and move some duplicated
code into a function.


# f649ab8b 21-Dec-2014 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Remove EXP_REDIR.

EXP_REDIR was supposed to generate pathnames in redirection if exactly one
file matches, as permitted but not required by POSIX in interactive mode. It
is unlikely this will be implemented.

No functional change is intended.

MFC after: 1 week


# 85bf1d2f 26-Feb-2014 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Make expari() static.


# 4dc6bdd3 03-Feb-2013 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Expand here documents in the current process.

Expand here documents at the same point other redirections are expanded but
use a non-fork subshell environment (like simple command substitutions) for
compatibility. Substitition errors result in an empty here document like
before.

As a result, a fork is avoided for short (<4K) expanded here documents.

Unexpanded here documents (with quoted end marker after <<) are not affected
by this change. They already only forked when >4K.

Side effects:
* Order of expansion is slightly different.
* Slow expansions are not executed in parallel with the redirected command.
* A non-fork subshell environment is subtly different from a forked process.


# 260fc3f4 01-Jan-2012 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Make various functions static.


# 454a02b3 13-Jun-2011 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Fix duplicate prototypes for builtins.

Have mkbuiltins write the prototypes for the *cmd functions to builtins.h
instead of builtins.c and include builtins.h in more .c files instead of
duplicating prototypes for *cmd functions in other headers.


# c543e1ae 12-Jun-2011 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Save/restore changed variables in optimized command substitution.

In optimized command substitution, save and restore any variables changed by
expansions (${var=value} and $((var=assigned))), instead of trying to
determine if an expansion may cause such changes.

If $! is referenced in optimized command substitution, do not cause jobs to
be remembered longer.

This fixes $(jobs $!) again, simplifies the man page and shortens the code.


# acd7984f 28-Dec-2010 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Don't do optimized command substitution if expansions have side effects.

Before considering to execute a command substitution in the same process,
check if any of the expansions may have a side effect; if so, execute it in
a new process just like happens if it is not a single simple command.

Although the check happens at run time, it is a static check that does not
depend on current state. It is triggered by:
- expanding $! (which may cause the job to be remembered)
- ${var=value} default value assignment
- assignment operators in arithmetic
- parameter substitutions in arithmetic except ${#param}, $$, $# and $?
- command substitutions in arithmetic

This means that $((v+1)) does not prevent optimized command substitution,
whereas $(($v+1)) does, because $v might expand to something containing
assignment operators.

Scripts should not depend on these exact details for correctness. It is also
imaginable to have the shell fork if and when a side effect is encountered
or to create a new temporary namespace for variables.

Due to the $! change, the construct $(jobs $!) no longer works. The value of
$! should be stored in a variable outside command substitution first.


# 048f2667 29-Oct-2010 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Do IFS splitting on word in ${v+word} and ${v-word}.

The code is inspired by NetBSD sh somewhat, but different because we
preserve the old Almquist/Bourne/Korn ability to have an unquoted part in a
quoted ${v+word}. For example, "${v-"*"}" expands to $v as a single field if
v is set, but generates filenames otherwise.

Note that this is the only place where we split text literally from the
script (the similar ${v=word} assigns to v and then expands $v). The parser
must now add additional markers to allow the expansion code to know whether
arbitrary characters in substitutions are quoted.

Example:
for i in ${$+a b c}; do echo $i; done

Exp-run done by: pav (with some other sh(1) changes)


# a7d5f7eb 19-Oct-2010 Jamie Gritton <jamie@FreeBSD.org>

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.


# fe0506d7 09-Mar-2010 Marcel Moolenaar <marcel@FreeBSD.org>

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.


# 2cac6e36 24-Dec-2009 Jilles Tjoelker <jilles@FreeBSD.org>

sh: Constify various strings.

Most of this is adding const keywords, but setvar() in var.c had to be
changed somewhat more.


# d7f03759 19-Oct-2008 Ulf Lilleengen <lulf@FreeBSD.org>

- Import the HEAD csup code which is the basis for the cvsmode work.


# 6195fb41 06-Apr-2004 Mark Murray <markm@FreeBSD.org>

Remove clause 3 from the UCB licenses.

OK'ed by: imp, core


# 2c25061f 26-Dec-2002 Tim J. Robbins <tjr@FreeBSD.org>

Add the "wordexp" shell built-in command which will be used to implement
the POSIX wordexp() function.


# 5134c3f7 01-Feb-2002 Warner Losh <imp@FreeBSD.org>

o __P has been reoved
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
they already are.
o Change
int
foo() {
...
to
int
foo(void)
{
...


# 2a456239 27-Aug-1999 Peter Wemm <peter@FreeBSD.org>

$Id$ -> $FreeBSD$


# 8b220a61 09-Apr-1999 Tor Egge <tegge@FreeBSD.org>

When a variable expansion is enclosed in double quotes, the internal
representation of the expression is quoted. Take care of this when
doing pattern matching in conjunction with trimming.

#!/bin/sh
c=d:e; echo "${c%:e}"

PR: NetBSD PR#7231
Noticed by: Havard Eidnes <Havard.Eidnes@runit.sintef.no>


# 5557a02a 13-Sep-1998 Tor Egge <tegge@FreeBSD.org>

Be more consistent with handling of quote mark control character.
Don't output double-quotes inside variable expansion/arithmetic
expansion region in here-documents. When leaving the arithmetic
expansion syntax mode, adjust the dblquote flag according to
previous syntax, in order to avoid splitting of quoted variables.


# 6f47734f 06-Sep-1998 Tor Egge <tegge@FreeBSD.org>

Better handling of word splitting. Don't record the same region
multiple times when performing nested variable expansion, and
preserve some quoting information in order to avoid removing
apparently empty expansion result.


# b97fa2ef 22-Feb-1997 Peter Wemm <peter@FreeBSD.org>

Revert $FreeBSD$ to $Id$


# 1130b656 14-Jan-1997 Jordan K. Hubbard <jkh@FreeBSD.org>

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.


# aa9caaf6 01-Sep-1996 Peter Wemm <peter@FreeBSD.org>

Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault... mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do. The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter


# 069428af 26-May-1996 Peter Wemm <peter@FreeBSD.org>

Import the 4.4BSD-Lite2 /bin/sh sources

Requested by: joerg

(Note, this is mostly going to be conflicts, which is expected. Our entire
sh source has a mainline, so this should not change anything except for
a few new files appearing. I dont think they are a problem)


# 89730b29 23-Sep-1994 David Greenman <dg@FreeBSD.org>

Added $Id$


# 4b88c807 26-May-1994 Rodney W. Grimes <rgrimes@FreeBSD.org>

BSD 4.4 Lite bin Sources