Commit Graph

818 Commits

Author SHA1 Message Date
Jilles Tjoelker
4dc6bdd3e7 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.
2013-02-03 15:54:57 +00:00
Jilles Tjoelker
58570ac4a5 sh: Prefer our character classification functions to <ctype.h>. 2013-01-31 22:10:57 +00:00
Jilles Tjoelker
f9b7cc523d sh: Show negated commands (!) in jobs output. 2013-01-31 21:50:44 +00:00
Joel Dahl
cb5a6a58cb Add FILES section.
Discussed with:	jilles
2013-01-22 18:02:58 +00:00
Joel Dahl
5dd78c9f36 Change the $ENV example to use .shrc instead of .shinit. This is consistent
with what we use in /usr/share/skel/dot.profile.

Discussed with: jilles
2013-01-20 22:25:25 +00:00
Jilles Tjoelker
84edde8b1a sh: Move some stackmarks to fix high memory usage in some loops.
If a loop contained certain commands (such as redirected compound commands),
the temporary memory for the redirection was not freed between iterations of
the loop but only after the loop.

Put a stackmark in evaltree(), freeing memory whenever a node has been
evaluated. Some other stackmarks are then redundant; remove them.

Example:
  while :; do { :; } </dev/null; done
2013-01-20 21:28:05 +00:00
Jilles Tjoelker
59e0cc8e4a sh: Remove mkinit's initialization routine.
Instead, call the only init function left directly from main().
2013-01-20 12:44:50 +00:00
Jilles Tjoelker
60a6bf2a5a sh: Replace an mkinit use with an initialization. 2013-01-19 22:12:08 +00:00
Jilles Tjoelker
523646ee5c sh: Simplify cd-hash interaction.
Instead of rechecking relative paths for all hashed utilities after a cd,
track if any utility in cmdtable depends on a relative path in PATH.
If there is such a utility, cd clears the entire table.

As a result, the '*' in hash no longer happens.
2013-01-14 16:40:50 +00:00
Jilles Tjoelker
925420d09c sh: Pass $? to command substitution containing compound/multiple commands.
Example:
  false; echo $(echo $?; :)
2013-01-14 12:20:55 +00:00
Jilles Tjoelker
31d396587e sh: Fix crash when parsing '{ } &'.
MFC after:	1 week
2013-01-13 19:26:33 +00:00
Jilles Tjoelker
2c090c7168 sh: Don't lose $? when backquoted command ends with semicolon or newline.
An empty simple command was added and overwrote the exit status with 0.

This affects `...` but not $(...).

Example:
  v=`false;`; echo $?
2013-01-13 19:19:40 +00:00
Jilles Tjoelker
cdbd40cbb2 sh: Prefer strsignal() to accessing sys_siglist directly.
Accessing sys_siglist directly requires rtld to copy it from libc to the sh
executable's BSS. Also, strsignal() will put in the signal number for
unknown signals (FreeBSD-specific) so we need not do that ourselves.

Unfortunately, there is no function for sys_signame.
2012-12-25 14:17:09 +00:00
Jilles Tjoelker
d6d66cfc00 sh: Detect and flag write errors on stdout in builtins.
If there is a write error on stdout, a message will be printed (to stderr)
and the exit status will be changed to 2 if it would have been 0 or 1.

PR:		bin/158206
2012-12-12 22:01:10 +00:00
Jilles Tjoelker
22bec20ba9 sh: Remove an unused variable. 2012-11-14 14:08:24 +00:00
Jilles Tjoelker
35dab8598a sh: Forward-declare struct alias instead of giving up type safety via void * 2012-11-11 15:13:24 +00:00
Jilles Tjoelker
e964872f18 sh: Fix two issues when an alias is redefined:
* The last character is not displayed.
 * If the alias ends with itself (as a word), an infinite memory-eating loop
   occurs.

If an alias is defined initially, a space is appended to avoid recursion but
this did not happen when an alias was later modified.

PR:		bin/173418
Submitted by:	Daniel F.
MFC after:	1 week
2012-11-08 13:33:48 +00:00
Jilles Tjoelker
d172408c7e sh: Change cmdtype in tblentry from short to signed char.
If this is a smaller type than int anyway, we can make it the smallest
possible.
2012-11-05 17:52:18 +00:00
Jilles Tjoelker
422c281c83 sh: Use C99 flexible array instead of accessing array beyond bounds.
Although sufficient memory is available for a longer string in cmdname,
this is undefined behaviour anyway.

Side effect: for alignment reasons, an additional byte of memory is
allocated per hashed command.
2012-11-03 22:23:08 +00:00
Joel Dahl
a2442c2fa9 mdoc: don't nest displays. The markup here isn't adding anything anyway.
Fixes a mandoc lint warning.

Discussed with:	brueffer, Jason McIntyre <jmc@kerhand.co.uk>
2012-10-14 13:59:17 +00:00
Jilles Tjoelker
7cbda73825 sh: Prefer internal nextopt() to libc getopt().
This reduces code duplication and code size.

/usr/bin/printf is not affected.

Side effect: different error messages when certain builtins are passed
invalid options.
2012-09-15 21:56:30 +00:00
Jilles Tjoelker
d902a66b99 sh: Reduce code duplication: use setinputfile instead of open/setinputfd
combination.

MFC after:	2 weeks
2012-09-14 15:22:15 +00:00
Joel Dahl
afc5a69a1d Minor mdoc fix. 2012-09-11 17:57:03 +00:00
Jilles Tjoelker
36f7fbeae8 sh: Remove XXX comment about removing nextopt().
Using nextopt() avoids depending on the BSD-specific optreset feature in
getopt() and reduces code size (both source and binary).
2012-09-08 19:24:03 +00:00
Jilles Tjoelker
1794251add sh: Fix EINTR race condition in "wait" and "set -T" using sigsuspend().
When waiting for child processes using "wait" or if "set -T" is in effect, a
signal interrupts the wait. Make sure there is no window where the signal
handler may be invoked (setting a flag) just before going to sleep.

There is a similar race condition in the shell language, but scripts can
avoid it by exiting from the trap handler or enforcing synchronization using
a fifo.

If SIGCHLD is not trapped, a signal handler must be installed for it. Only
install this handler for the duration of the wait to avoid triggering
unexpected [EINTR] errors elsewhere.

Note that for some reason only SIGINT and SIGQUIT interrupt a "wait"
command. This remains the case.
2012-07-29 18:04:38 +00:00
Jilles Tjoelker
fb05913c5d sh: Do not ask for stopped/continued processes if we do not need them
rather than retrying wait3 if they happen.
2012-07-28 15:13:48 +00:00
Jilles Tjoelker
61fb716ac9 sh: Inline waitproc() into its only caller. 2012-07-28 14:56:50 +00:00
Jilles Tjoelker
faa787d323 sh: Track continued jobs (even if not continued by bg or fg).
This uses wait3's WCONTINUED flag.

There is no message for this. The change is visible in "jobs" or if the job
stops again.
2012-07-28 14:32:55 +00:00
Jilles Tjoelker
fa7ccda2c4 sh: Reset pendingsigs before checking pending traps, not after.
Otherwise, a signal arriving at exactly the right moment might not be
processed until another signal arrived.
2012-07-15 11:18:52 +00:00
Jilles Tjoelker
184dcee217 sh: Remove unused variable in_dowait. 2012-07-15 10:49:16 +00:00
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
Pedro F. Giffuni
00c43e0ca4 Merge libedit adjustment from NetBSD.
On recent versions of NetBSD's libedit, el_gets
now sets el_len to -1 on error so we can
distinguish between a NULL string and an error.

This fixes sh from exiting with newer versions
of libedit now allowing EINTR to return.

Obtained from:	NetBSD
Reviewed by:	jilles
MFC after:	3 weeks
2012-07-11 22:17:58 +00:00
Marcel Moolenaar
937b0a997b Work better with how make/bmake works:
1.  Avoid a cd back into ${.CURDIR} to run mkbuiltins when we know make
    will first cd into ${.OBJDIR}. Keep the cwd to what make sets it to.
2.  Don't tell mkbuiltins where to write to (= ${.OBJDIR}), but where to
    get sources from (= ${.CURDIR}). This to compensate for point 1.

This fixes a problem with bmake's mk files that optimize ${.OBJDIR} to
expand to "." after changing cwd, not taking into account that the
target is pretty much undoing that and not getting the full path to the
object tree anymore.
2012-05-24 19:48:15 +00:00
Jilles Tjoelker
ad859ed8cf sh: Remove an unused header.
The read builtin no longer does things with termios.
2012-05-15 22:50:47 +00:00
Joel Dahl
35471bf8ef Minor mdoc nits. 2012-05-13 14:16:04 +00:00
Joel Dahl
748611c9c0 mdoc: fix column names, indentation, column separation within each row, and
quotation. Also make sure we have the same amount of columns in each row as
the number of columns we specify in the head arguments.

Reviewed by:	brueffer
2012-04-07 09:05:30 +00:00
Jilles Tjoelker
b95fca474d sh: Fix build with -DDEBUG=2.
Reported by:	Kristof Provost
MFC after:	1 week
2012-04-02 17:16:24 +00:00
Eitan Adler
50d675f7a9 Remove trailing whitespace per mdoc lint warning
Disussed with:	gavin
No objection from:	doc
Approved by:	joel
MFC after:	3 days
2012-03-29 05:02:12 +00:00
Joel Dahl
904d0726c8 Remove superfluous paragraph macro. 2012-03-25 09:20:14 +00:00
Jilles Tjoelker
c0b3cf0676 sh: Make 'hash' return 1 if at least one utility is not found.
Reported by:	lme
2012-02-11 21:06:45 +00:00
Jilles Tjoelker
33233ec76e sh: Fix swapped INTON/INTOFF.
A possible consequence of this bug was a memory leak if SIGINT arrived
during a 'set' command (listing variables).

MFC after:	1 week
2012-02-04 23:29:07 +00:00
Jilles Tjoelker
caf29fab8c sh: Use vfork in a few common cases.
This uses vfork() for simple commands and command substitutions containing a
single simple command, invoking an external program under certain conditions
(no redirections or variable assignments, non-interactive shell, no job
control). These restrictions limit the amount of code executed in a vforked
child.

There is a large speedup (for example 35%) in microbenchmarks. The
difference in buildkernel is smaller (for example 0.5%) but still
statistically significant. See
http://lists.freebsd.org/pipermail/freebsd-hackers/2012-January/037581.html
for some numbers.

The use of vfork() can be disabled by setting a variable named
SH_DISABLE_VFORK.
2012-02-04 23:12:14 +00:00
Philippe Charnier
2fae4c3d95 Add prototypes, ANSIfy functions definitions to reduce WARNS=6 output. 2012-01-25 08:42:19 +00:00
Jilles Tjoelker
6eff4a75d5 sh: Fix $? in the first command of a 'for'.
In the first command of a 'for', $? should be the exit status of the last
pipeline (command substitution in the word list or command before 'for'),
not always 0.
2012-01-22 14:00:33 +00:00
Jilles Tjoelker
0105d7224d sh: Remove "kill" example function, which is superseded by the kill builtin
MFC after:	1 week
2012-01-21 20:39:17 +00:00
Jean-Sébastien Pédron
01a43bcf7b sh: Fix execution of multiple statements in a trap when evalskip is set
Before this fix, only the first statement of the trap was executed if
evalskip was set. This is for example the case when:
    o  "-e" is set for this shell
    o  a trap is set on EXIT
    o  a function returns 1 and causes the script to abort

Reviewed by:	jilles
MFC after:	2 weeks
2012-01-16 11:07:46 +00:00
Jilles Tjoelker
93fcb2511b sh: Fix some bugs with exit status from case containing ;&.
Also, rework evalcase() to not evaluate any tree. Instead, return the
NCLISTFALLTHRU node and handle it in evaltree().

Fixed bugs:

* If a ;& list with non-zero exit status is followed by an empty ;; or final
  list, the exit status of the case command should be equal to the exit
  status of the ;& list, not 0.

* An empty ;& case should not reset $?.
2012-01-15 21:39:38 +00:00
Jilles Tjoelker
92371efca2 sh: Fix two bugs with case and exit status:
* If no pattern is matched, POSIX says the exit status shall be 0 (even if
  there are command substitutions).
* If a pattern is matched and there are no command substitutions, the first
  command should see the $? from before the case command, not always 0.
2012-01-15 20:04:05 +00:00
Jilles Tjoelker
7f40c1f876 sh: Change input buffer size from 1023 to 1024.
PR:		bin/161756
2012-01-14 22:46:18 +00:00
Jilles Tjoelker
52c450395a sh: Fix out of bounds array access when trap is used with an invalid signal.
MFC after:	1 week
2012-01-14 21:54:12 +00:00