Commit Graph

2586 Commits

Author SHA1 Message Date
Jilles Tjoelker
c76aed958b sh: Change the CTL* bytes to ones invalid in UTF-8.
This ensures that mbrtowc(3) can be used directly once it has been verified
that there is no CTL* byte. Dealing with a CTLESC byte within a multibyte
character would be complicated.

The new values do occur in iso-8859-* encodings. This decreases efficiency
slightly but should not affect correctness.

Caveat: Updating across this change and rebuilding without cleaning may
yield a subtly broken sh binary. By default, make buildworld will clean and
avoid problems.
2011-05-06 20:45:50 +00:00
Jilles Tjoelker
a62ab0274a sh: Add $'quoting' (C-style escape sequences).
A string between $' and ' may contain backslash escape sequences similar to
the ones in a C string constant (except that a single-quote must be escaped
and a double-quote need not be). Details are in the sh(1) man page.

This construct is useful to include unprintable characters, tabs and
newlines in strings; while this can be done with a command substitution
containing a printf command, that needs ugly workarounds if the result is to
end with a newline as command substitution removes all trailing newlines.

The construct may also be useful in future to describe unprintable
characters without needing to write those characters themselves in 'set -x',
'export -p' and the like.

The implementation attempts to comply to the proposal for the next issue of
the POSIX specification. Because this construct is not in POSIX.1-2008,
using it in scripts intended to be portable is unwise.

Matching the minimal locale support in the rest of sh, the \u and \U
sequences are currently not useful.

Exp-run done by: pav (with some other sh(1) changes)
2011-05-05 20:55:55 +00:00
Jilles Tjoelker
3937fc9c26 sh: Apply set -u to variables in arithmetic.
Note that this only applies to variables that are actually used.
Things like (0 && unsetvar) do not cause an error.

Exp-run done by: pav (with some other sh(1) changes)
2011-05-04 22:12:22 +00:00
Jilles Tjoelker
fc0818fef3 sh: Detect an error for ${#var<GARBAGE>}.
In particular, this makes things like ${#foo[0]} and ${#foo[@]} errors
rather than silent equivalents of ${#foo}.

PR:		bin/151720
Submitted by:	Mark Johnston
Exp-run done by: pav (with some other sh(1) changes)
2011-05-04 21:49:34 +00:00
Ruslan Ermilov
a35a58824b Don't call -f option's argument "stdin".
MFC after:	3 days
2011-05-03 10:08:11 +00:00
Jilles Tjoelker
03b3a844d0 sh: Set $? to 0 for background commands.
For backgrounded pipelines and subshells, the previous value of $? was being
preserved, which is incorrect.

For backgrounded simple commands containing a command substitution, the
status of the last command substitution was returned instead of 0.

If fork() fails, this is an error.
2011-04-25 20:54:12 +00:00
Jilles Tjoelker
92a1de471c sh: Check setuid()/setgid() return values.
If the -p option is turned off, privileges from a setuid or setgid binary
are dropped. Make sure to check if this succeeds. If it fails, this is an
error which will cause the shell to abort except in interactive mode or if
'command' was used to make 'set' or an outer 'eval' or '.' non-special.

Note that taking advantage of this feature and writing setuid shell scripts
seems unwise.

MFC after:	1 week
2011-04-25 10:14:29 +00:00
Jilles Tjoelker
b7b23db5e2 sh: Remove duplicate code resetting uid/gid for set +p/+o privileged.
MFC after:	1 week
2011-04-25 10:08:34 +00:00
Jilles Tjoelker
45496405c6 sh: Allow EV_EXIT through function calls, make {...} <redir more consistent.
If EV_EXIT causes an exit, use the exception mechanism to unwind
redirections and local variables. This way, if the final command is a
redirected command, an EXIT trap now executes without the redirections.

Because of these changes, EV_EXIT can now be inherited by the body of a
function, so do so. This means that a function no longer prevents a fork
before an exec being skipped, such as in
  f() { head -1 /etc/passwd; }; echo $(f)

Wrapping a single builtin in a function may still cause an otherwise
unnecessary fork with command substitution, however.

An exit command or -e failure still invokes the EXIT trap with the
original redirections and local variables in place.

Note: this depends on SHELLPROC being gone. A SHELLPROC depended on
keeping the redirections and local variables and only cleaning up the
state to restore them.
2011-04-23 22:28:56 +00:00
Jilles Tjoelker
caa7ccdc54 sh: Do not word split "${#parameter}".
This is only a problem if IFS contains digits, which is unusual but valid.

Because of an incorrect fix for PR bin/12137, "${#parameter}" was treated
as ${#parameter}. The underlying problem was that "${#parameter}"
erroneously added CTLESC bytes before determining the length. This
was properly fixed for PR bin/56147 but the incorrect fix was not backed
out.

Reported by:	Seeker on forums.freebsd.org
MFC after:	2 weeks
2011-04-20 22:24:54 +00:00
Edward Tomasz Napierala
b9ff20ab7e Document problems with -d/-w and the fact that -X is the default.
Suggested by:	arundel@
Reviewed by:	arundel@
2011-04-18 19:20:47 +00:00
Edward Tomasz Napierala
649fde88ff Get rid of DSIZ; instead just call the sizing function if provided. 2011-04-12 20:10:15 +00:00
Edward Tomasz Napierala
181b4eebb9 Make it possible to use permission sets (full_set, modify_set, read_set
and write_set) with setfacl(1).

PR:		kern/154113
Submitted by:	Shawn Webb <lattera at gmail dot com> (earlier version)
MFC after:	1 month
2011-04-09 07:42:25 +00:00
Edward Tomasz Napierala
f9db2550b2 Add proper width calculation for time fields (time, cputime and usertime).
This fixes the ugly overflow in "ps aux" output for "[idle]".
2011-03-24 20:15:42 +00:00
Edward Tomasz Napierala
3bf92decd3 Make "LOGIN" and "CLASS" columns width scale properly instead of wasting space. 2011-03-24 17:20:24 +00:00
Jilles Tjoelker
ef89d04f13 sh(1): Describe subshell environment, command substitution more correctly.
POSIX does not require the shell to fork for a subshell environment, and we
use that possibility in various ways (command substitutions with a single
command and most subshells that are the final command of a shell process).
Therefore do not tie subshells to forking in the man page.

Command substitutions with expansions are a bit strange, causing a fork for
$(...$(($x))...) because $x might expand to y=2; they will probably be
changed later but this is how they work now.
2011-03-20 23:52:45 +00:00
Konstantin Belousov
a870bf2c31 Implement the usertime and systime keywords for ps, printing the
corresponding times reported by getrusage().

Submitted by:	Dan Nelson <dnelson allantgroup com>
MFC after:	1 week
2011-03-17 11:25:32 +00:00
Jilles Tjoelker
0cf90cd1d3 bin: Prefer strrchr() to rindex().
This removes the last index/rindex usage from /bin.
2011-03-15 22:22:11 +00:00
Jilles Tjoelker
35c641ed21 sh: Fix some parameter expansion variants ${#...}.
These already worked: $# ${#} ${##} ${#-} ${#?}
These now work as well: ${#+word} ${#-word} ${##word} ${#%word}

There is an ambiguity in the standard with ${#?}: it could be the length of
$? or it could be $# giving an error in the (impossible) case that it is not
set. We continue to use the former interpretation as it seems more useful.
2011-03-13 20:02:39 +00:00
Stefan Farfeleder
5db2bbd692 Remove unnecessary cast.
Reviewed by:	jilles
2011-03-07 07:31:15 +00:00
Jilles Tjoelker
ea381e691a sh(1): Reduce excessive semicolon-separated sentences.
Reported by:	Benjamin Kaduk
2011-03-06 21:20:53 +00:00
Edward Tomasz Napierala
7123f4cd6f Export login class information via kinfo and make it possible to view
it using "ps -o class".
2011-03-05 14:41:49 +00:00
Jilles Tjoelker
976018d24f sh: Fix some warnings in code for arithmetic expressions.
Submitted by:	eadler
2011-03-05 13:27:13 +00:00
Jilles Tjoelker
3658c9776e kill: Note that this is used both as a normal program and a shell builtin. 2011-03-01 21:48:22 +00:00
Xin LI
eaea8924ce Accept == as an alias of = which is a popular GNU extension.
This is intentionally undocumented for now since it's not part
of any standard.

MFC after:	1 month
2011-02-27 12:28:06 +00:00
Hajimu UMEMOTO
35bb448cd6 When WITH_ICONV is set, use our in-tree iconv. 2011-02-26 18:54:54 +00:00
Sergey Kandaurov
440c834c54 mdoc(7) markup.
Approved by:	avg (mentor), kib (mentor)
MFC after:	3 days
2011-02-21 16:03:39 +00:00
Rebecca Cran
6bccea7c2b Fix typos - remove duplicate "the".
PR:	bin/154928
Submitted by:	Eitan Adler <lists at eitanadler.com>
MFC after: 	3 days
2011-02-21 09:01:34 +00:00
Jilles Tjoelker
2fd7d6aab6 test: Note that this is used both as a normal program and a shell builtin.
MFC after:	1 week
2011-02-15 22:17:47 +00:00
Jilles Tjoelker
e9749129ad sh: Detect dividing the smallest integer by -1.
This overflows and on some architectures such as amd64 it generates SIGFPE.
Generate an error on all architectures.
2011-02-12 23:44:05 +00:00
Rebecca Cran
f68fbfedc1 Fix typos.
PR:	docs/131625
Submitted by:	Andrew Wright <andrew at qemg.org>
MFC after:	1 month
2011-02-12 20:28:15 +00:00
Jilles Tjoelker
075b72ef01 sh(1): Update description of arithmetic. 2011-02-08 23:19:40 +00:00
Jilles Tjoelker
6262b84eee sh: Import arithmetic expression code from dash.
New features:
* proper lazy evaluation of || and &&
* ?: ternary operator
* executable is considerably smaller (8K on i386) because lex and yacc are
  no longer used

Differences from dash:
* arith_t instead of intmax_t
* imaxdiv() not used
* unset or null variables default to 0
* let/exp builtin (undocumented, will probably be removed later)

Obtained from:	dash
2011-02-08 23:18:06 +00:00
Jilles Tjoelker
b15e9aa322 sh: Fix two things about {(...)} <redir:
* In {(...) <redir1;} <redir2, do not drop redir1.
* Maintain the difference between (...) <redir and {(...)} <redir:
  In (...) <redir, the redirection is performed in the child, while in
  {(...)} <redir it should be performed in the parent (like {(...); :;}
  <redir)
2011-02-05 15:02:19 +00:00
Jilles Tjoelker
c059d82290 sh: Remove clearcmdentry()'s now unused argument. 2011-02-05 14:08:51 +00:00
Jilles Tjoelker
ef0cb80dd4 sh: Forget all cached command locations on any PATH change.
POSIX requires this and it is simpler than the previous code that remembered
command locations when appending directories to PATH.

In particular,
  PATH=$PATH
is no longer a no-op but discards all cached command locations.
2011-02-05 14:01:46 +00:00
Jilles Tjoelker
604e8224f8 sh: Do not try to execute binary files as scripts.
If execve() returns an [ENOEXEC] error, check if the file is binary before
trying to execute it using sh. A file is considered binary if at least one
of the first 256 bytes is '\0'.

In particular, trying to execute ELF binaries for the wrong architecture now
fails with an "Exec format error" message instead of syntax errors and
potentially strange results.
2011-02-05 12:54:59 +00:00
Jilles Tjoelker
3835f47c7e sh: Remove special code for shell scripts without magic number.
These are called "shell procedures" in the source.

If execve() failed with [ENOEXEC], the shell would reinitialize itself
and execute the program as a script. This requires a fair amount of code
which is not frequently used (most scripts have a #! magic number).
Therefore just execute a new instance of sh (_PATH_BSHELL) to run the
script.
2011-02-04 22:47:55 +00:00
Jilles Tjoelker
12dacf622b Make sys_signame upper case.
This matches the constants from <signal.h> with 'SIG' removed, which POSIX
requires kill and trap to accept and 'kill -l' to write.

'kill -l', 'trap', 'trap -l' output is now upper case.

In Turkish locales, signal names with an upper case 'I' are now accepted,
while signal names with a lower case 'i' are no longer accepted, and the
output of 'killall -l' now contains proper capital 'I' without dot instead
of a dotted capital 'I'.
2011-02-04 16:40:50 +00:00
Jilles Tjoelker
834d160b3a sh: Return only 126 or 127 for execve() failures.
Do not return 2 for errors other than [EACCES] or [ENOENT].
2011-02-03 23:38:11 +00:00
Jilles Tjoelker
3e0b768c63 sh: Remove comment mentioning herefd, which is gone. 2011-02-02 21:48:53 +00:00
Jilles Tjoelker
b9f696953d sh: Send messages about signals to stderr.
This is required by POSIX and seems to make more sense.

See also r217557.
2011-01-30 22:57:52 +00:00
Jilles Tjoelker
cff1d84937 sh: Clean up some old comments:
* There is no plan for an alternative to the command "set".
* Attempting to unset a readonly variable has not raised an error for quite
  a while, so the order of unsetting a variable and a function with the same
  name does not matter.

MFC after:	1 week
2011-01-25 20:56:18 +00:00
Konstantin Belousov
f5f3977b8d Document P_FOLLOWFORK.
MFC after:	2 weeks
2011-01-25 11:04:16 +00:00
Jilles Tjoelker
0d5ccb45d8 sh: Fix signal messages being sent to the wrong file sometimes.
When a foreground job exits on a signal, a message is printed to stdout
about this. The buffer was not flushed after this which could result in the
message being written to the wrong file if the next command was a builtin
and had stdout redirected.

Example:
  sh -c 'kill -9 $$'; : > foo; echo FOO:; cat foo

Reported by:	gcooper
MFC after:	1 week
2011-01-18 21:18:31 +00:00
Jilles Tjoelker
421fb02139 sh(1): Document changes to 'exit' from traps. 2011-01-16 14:11:50 +00:00
Jilles Tjoelker
ebdfd6dc4d sh: If exit is used without args from a trap action, exit on the signal.
This is useful so that it is easier to exit on a signal than to reset the
trap to default and resend the signal. It matches ksh93. POSIX says that
'exit' without args from a trap action uses the exit status from the last
command before the trap, which is different from 'exit $?' and matches this
if the previous command is assumed to have exited on the signal.

If the signal is SIGSTOP, SIGTSTP, SIGTTIN or SIGTTOU, or if the default
action for the signal is to ignore it, a normal _exit(2) is done with exit
status 128+signal_number.
2011-01-16 13:56:41 +00:00
Jilles Tjoelker
a043cc4c68 sh: Fix some things about -- in trap:
* Make 'trap --' do the same as 'trap' instead of nothing.
* Make '--' stop option processing (note that '-' action is not an option).

Side effect: The error message for an unknown option is different.
2011-01-15 21:09:00 +00:00
Jilles Tjoelker
45b3c17647 sh: Make 'trap -l' look like 'kill -l'. 2011-01-14 21:30:27 +00:00
Jilles Tjoelker
33a8413363 sh: Follow-up to r216743, grabstackblock() can be replaced with stalloc().
grabstackblock() was used only once (but it is a very often executed piece
of code).
2011-01-09 22:47:58 +00:00