Home | History | Annotate | Download | only in sh
History log of /src/bin/sh/memalloc.c
RevisionDateAuthorComments
 1.41  07-May-2025  kre Obliterate the global var herefd

For the past several years (since Nov 2021) the global var "herefd"
has led a rather meaningless existence.

It gets statically init'd to -1 (at compile time), and several
times its value is carefully saved, set to -1, then restored later.
(Lots of copying around of -1 going on there!)

The only use of its value was removed in the immediately previous update
to memalloc.c, where it was tested, and if its value were >= 0 ...
(no point mentioning what would happen, since its value is always -1,
since Nov 2021).

Bye bye herefd, it was nice knowing you. May we never meet again.
 1.40  06-May-2025  kre PR bin/59395 Remove some dead code.

Back in Nov 2021, the way here docs were implemented was changed
to fix problem report 53550 and this code can no longer ever
be executed (it is impossible without reintroducing the 53550
problems), so time for it to go.

This will make no functional difference to sh in HEAD,
and wouldn't in -10, if this were worth pulling up there (it isn't).

However, in -9 this code still runs (in the relatively rare cases
that it applies), but is broken, leading to the problem in 59395.
Removing this code, which is just an optimisation, will correct
that problem (for current releases only -9 is affected).

XXX pullup -9 (will fix PR bin/59395)
 1.39  07-Apr-2023  kre branches: 1.39.2;

Remove an end of file trailing blank line that served no purpose.

NFCI
 1.38  07-Apr-2023  kre The great shell trailing whitespace cleanup of 2023...
Inspired by private e-mail comments from mouse@

NFCI.
 1.37  31-May-2022  andvar fix various typos in comments, documentation and messages.
 1.36  10-Apr-2022  andvar fix various typos in comments and output/log messages.
 1.35  26-Oct-2021  kre Use a type-correct end marker for strstrcat() rather than NULL, as
for a function with unknown number & types of args, the compiler isn't
able to automatically convert to the correct type. Issue pointed out
in off list e-mail by Rolland Illig ... Thanks.

The first arg (pointer to where to put length of result) is of a known
type, so doesn't have the same issue - we can keep using NULL for that
one when the length isn't needed.

Also, make sure to return a correctly null terminated null string in
the (absurd) case that there are no non-null args to strstrcat() (though
there are much better ways to generate "" on the stack). Since there is
currently just one call in the code, and it has real string args, this
isn't an issue for now, but who knows, some day.

NFCI - if there is any real change, then it is a change that is required.

XXX pullup -9 (together with the previous changes)
 1.34  26-Oct-2021  kre PR bin/56464

After almost 30 years, finally do the right thing and read $HOME/.profile
rather than .profile in the initial directory (it was that way in version
1.1 ...) All other ash descendants seem to have fixed this long ago.

While here, copy a feature from FreeBSD which allows "set +p" (if a
shell run by a setuid process with the -p flag is privileged) to reset
the privileges. Once done (the set +p) it cannot be undone (a later
set -p sets the 'p' flag, but that's all it does) - that just becomes a
one bit storage location.

We do this, as (also copying from FreeBSD, and because it is the right
thing to do) we don't run .profile in a privileged shell - FreeBSD run
/etc/suid_profile in that case (not a good name, it also applies to setgid
shells) but I see no real need for that, we run /etc/profile in any case,
anything that would go in /etc/suid_profile can just go in /etc/profile
instead (with suitable guards so the commands only run in priv'd shells).

One or two minor DEBUG mode changes (notably having priv'd shells identify
themselves in the DEBUG trace) and sh.1 changes with doc of the "set +p"
change, the effect that has on $PSc and a few other wording tweaks.

XXX pullup -9 (not -8, this isn't worth it for the short lifetime
that has left - if it took 28+ years for anyone to notice this, it
cannot be having all that much effect).
 1.33  09-Feb-2019  kre branches: 1.33.2;

INTON / INTOFF audit and cleanup.

No visible differences expected - there is a remote chance that
some internal lossage may no longer occur in interactive shells
that receive SIGINT (untrapped) at inopportune times, but you would
have had to have been very unlucky to have ever suffered from that.
 1.32  22-Aug-2018  kre Fix (hopefully) the problem reported on current-users by Patrick Welche.
we had incorrect usage of setstackmark()/popstackmark()

There was an ancient idiom (imported from CSRG in 1993) where code
can do:
setstackmark(&smark); loop until whatever condition {
/* do lots of code */ popstackmark(&smark);
} popstackmark(&smark);

The 1st (inner) popstackmark() resets the stack, conserving memory,
The 2nd one is needed just in case the "whatever condition" was never
true, and the first one was never executed.

This is (was) safe as all popstackmark() did was reset the stack.
That could be done over and over again with no harm.

That is, until 2000 when a fix from FreeBSD for another problem was
imported. That connected all the stack marks as a list (so they can be
located). That caused the problem, as the idiom was not changed, now
there is this list of marks, and popstackmark() was removing an entry.

It rarely (never?) caused any problems as the idiom was rarely used
(the shell used to do loops like above, mostly, without the inner
popstackmark()). Further, the stack mark list is only ever used when
a memory block is realloc'd.

That is, until last weekend - with the recent set of changes.

Part of that copied code from FreeBSD introduced the idiom above
into more functions - functions used much more, and with a greater
possibility of stack marks being set on blocks that are realloc'd
and so cause the problem. In the FreeBSD code, they changed the idiom,
and always do a setstackmark() immediately after the inner popstackmark().
But not for reasons related to a list of stack marks, as in the
intervening period, FreeBSD deleted that, but for another reason.

We do not have their issue, and I did not believe that their
updated idiom was needed (I did some analysis of exactly this issue -
just missed the important part!), and just continued using the old one.
Hence Patrick's core dump....

The solution used here is to split popstackmark() into 2 halves,
popstackmark() continues to do what it has (recently) done,
but is now implemented as a call of (a new func) rststackmark()
which does all the original work of popstackmark - but not removing
the entry from the stack mark list (which remains in popstackmark()).
Then in the idiom above, the inner popstackmark() turns into a call of
rststackmark() so the stack is reset, but the stack mark list is
unchanged. Tail recursion elimination makes this essentially free.
 1.31  22-Jul-2018  kre Minor cleanups to growstackblock(). This should really change
nothing that matters, but might be slightly more robust/complete.
 1.30  17-Jun-2017  kre branches: 1.30.4; 1.30.6;
Many internal memory management type fixes.

PR bin/52302 (core dump with interactive shell, here doc and error
on same line) is fixed. (An old bug.)

echo "$( echo x; for a in $( seq 1000 ); do printf '%s\n'; done; echo y )"
consistently prints 1002 lines (x, 1000 empty ones, then y) as it should
(And you don't want to know what it did before, or why.) (Another old one.)

(Recently added) Problems with ~ expansion fixed (mem management related).

Proper fix for the cwrappers configure problem (which includes the quick
fix that was done earlier, but extends upon that to be correct). (This was
another newly added problem.)

And the really devious (and rare) old bug - if STACKSTRNUL() needs to
allocate a new buffer in which to store the \0, calculate the size of
the string space remaining correctly, unlike when SPUTC() grows the
buffer, there is no actual data being stored in the STACKSTRNUL()
case - the string space remaining was calculated as one byte too few.
That would be harmless, unless the next buffer also filled, in which
case it was assumed that it was really full, not one byte less, meaning
one junk char (a nul, or anything) was being copied into the next (even
bigger buffer) corrupting the data.

Consistent use of stalloc() to allocate a new block of (stack) memory,
and grabstackstr() to claim a block of (stack) memory that had already
been occupied but not claimed as in use. Since grabstackstr is implemented
as just a call to stalloc() this is a no-op change in practice, but makes
it much easier to comprehend what is really happening. Previous code
sometimes used stalloc() when the use case was really for grabstackstr().
Change grabstackstr() to actually use the arg passed to it, instead of
(not much better than) guessing how much space to claim,

More care when using unstalloc()/ungrabstackstr() to return space, and in
particular when the stack must be returned to its previous state, rather than
just returning no-longer needed space, neither of those work. They also don't
work properly if there have been (really, even might have been) any stack mem
allocations since the last stalloc()/grabstackstr(). (If we know there
cannot have been then the alloc/release sequence is kind of pointless.)
To work correctly in general we must use setstackmark()/popstackmark() so
do that when needed. Have those also save/restore the top of stack string
space remaining.

[Aside: for those reading this, the "stack" mentioned is not
in any way related to the thing used for maintaining the C
function call state, ie: the "stack segment" of the program,
but the shell's internal memory management strategy.]

More comments to better explain what is happening in some cases.
Also cleaned up some hopelessly broken DEBUG mode data that were
recently added (no effect on anyone but the poor semi-human attempting
to make sense of it...).

User visible changes:

Proper counting of line numbers when a here document is delimited
by a multi-line end-delimiter, as in

cat << 'REALLY
END'
here doc line 1
here doc line 2
REALLY
END

(which is an obscure case, but nothing says should not work.) The \n
in the end-delimiter of the here doc (the last one) was not incrementing
the line number, which from that point on in the script would be 1 too
low (or more, for end-delimiters with more than one \n in them.)

With tilde expansion:
unset HOME; echo ~
changed to return getpwuid(getuid())->pw_home instead of failing (returning ~)

POSIX says this is unspecified, which makes it difficult for a script to
compensate for being run without HOME set (as in env -i sh script), so
while not able to be used portably, this seems like a useful extension
(and is implemented the same way by some other shells).

Further, with
HOME=; printf %s ~
we now write nothing (which is required by POSIX - which requires ~ to
expand to the value of $HOME if it is set) previously if $HOME (in this
case) or a user's directory in the passwd file (for ~user) were a null
STRING, We failed the ~ expansion and left behind '~' or '~user'.
 1.29  15-Feb-2008  matt branches: 1.29.62;
Fix inconsistent definitions
 1.28  07-Aug-2003  agc branches: 1.28.22;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22249, verified by myself.
 1.27  22-Jan-2003  dsl Support command -p, -v and -V as posix
Stop temporary PATH assigments messing up hash table
Fix sh -c -e "echo $0 $*" -a x (as posix)
(agreed by christos)
 1.26  24-Nov-2002  christos Fixes from David Laight:
- ansification
- format of output of jobs command (etc)
- job identiers %+, %- etc
- $? and $(...)
- correct quoting of output of set, export -p and readonly -p
- differentiation between nornal and 'posix special' builtins
- correct behaviour (posix) for errors on builtins and special builtins
- builtin printf and kill
- set -o debug (if compiled with DEBUG)
- cd src obj (as ksh - too useful to do without)
- unset -e name, remove non-readonly variable from export list.
(so I could unset -e PS1 before running the test shell...)
 1.25  07-Oct-2002  christos - it is wrong to put inton/intoff arount ckmalloc(), because the code
around it is the one that does this.
- whitespace fixes.
 1.24  04-Oct-2002  christos Rename ALIGN to SHELL_ALIGN and simplify macro so that it does not have side
effects, and add double to it, so that it aligns doubles correctly too. This
is just a workaround to fix the sparc64 problem where ALIGN() is now defined
in some include file to be 16 instead of 8. Thanks to martin for debugging this.
 1.23  01-Nov-2000  christos PR/11283: Hubert Feyrer: random memory corruption executing commands:
Fix from FreeBSD:

growstackblock() sometimes relocates a stack_block considered empty
without properly relocating stack marks referencing that block.
The first call to popstackmark() with the unrelocated stack mark
as argument then causes sh to abort.

Relocating the relevant stack marks seems to solve this problem.

The patch changes the semantics of popstackmark() somewhat. It can
only be called once after a call to setstackmark(), thus cmdloop() in
main.c needs an extra call to setstackmark().
 1.22  21-Oct-2000  mycroft Wrap malloc() calls with an INTOFF/INTON pair. Fixes PR 8414.
 1.21  31-Jan-1998  christos branches: 1.21.10;
Include our local includes after the system's ones.
 1.20  04-Jul-1997  christos branches: 1.20.2;
Fix compiler warnings.
 1.19  11-Jan-1997  tls kill 'register'
 1.18  16-Oct-1996  christos PR/2808: Remove trailing whitespace (from FreeBSD)
 1.17  20-May-1996  cgd branches: 1.17.2;
Fix growstackblock() 'newlen' calculations:
(1) it needs to be ALIGNed for both halves of the 'if,' and
(2) if you're going to claim that you now have ALIGN(newlen)
bytes left, you should have actually allocated
ALIGN(newlen), rather than just 'newlen' bytes.
 1.16  11-May-1995  christos Merge in my changes from vangogh, and fix the x=`false`; echo $? == 0
bug.
 1.15  21-Mar-1995  cgd convert to new RCS id conventions.
 1.14  31-Dec-1994  mycroft Fix that last bug in a less expensive way.
 1.13  31-Dec-1994  cgd take two: make grabstackstr() work correctly, in the face of strange filling.
 1.12  30-Dec-1994  mycroft Remove previous misguided change.
 1.11  23-Dec-1994  cgd don't play fast and loose with memory block allcation. try to allocate
in more-round sizes, but realize that not everybody will fill them up
exactly.
 1.10  04-Dec-1994  cgd from James Jegers <jimj@miller.cs.uwm.edu>: quiet -Wall, and squelch
some of the worst style errors.
 1.9  23-Sep-1994  mycroft Eliminate uses of some obsolete functions.
 1.8  11-Jun-1994  mycroft Add RCS ids.
 1.7  12-May-1994  jtc use prototypes provided by header files instead of our own
 1.6  12-May-1994  jtc Include appropriate header files to bring function prototypes into scope.
 1.5  11-May-1994  jtc sync with 4.4lite
 1.4  01-Aug-1993  mycroft Add RCS identifiers.
 1.3  23-Mar-1993  cgd changed "Id" to "Header" for rcsids
 1.2  22-Mar-1993  cgd added rcs ids to all files
 1.1  21-Mar-1993  cgd branches: 1.1.1;
Initial revision
 1.1.1.2  11-May-1994  jtc 44lite code
 1.1.1.1  21-Mar-1993  cgd initial import of 386bsd-0.1 sources
 1.17.2.1  26-Jan-1997  rat Update /bin/sh from trunk per request of Christos Zoulas. Fixes
many bugs.
 1.20.2.1  08-May-1998  mycroft Sync with trunk, per request of christos.
 1.21.10.2  03-Nov-2000  tv Pullup 1.23 [hubertf]:
Fixes PR 11283.
 1.21.10.1  22-Oct-2000  tv Pullup 1.22 [he]:
Wrap malloc() calls with an INTOFF/INTON pair. Fixes PR 8414.
 1.28.22.1  23-Mar-2008  matt sync with HEAD
 1.29.62.1  23-Jul-2017  snj Pull up following revision(s) (requested by kre in ticket #103):
bin/kill/kill.c: 1.28
bin/sh/Makefile: 1.111-1.113
bin/sh/arith_token.c: 1.5
bin/sh/arith_tokens.h: 1.2
bin/sh/arithmetic.c: 1.3
bin/sh/arithmetic.h: 1.2
bin/sh/bltin/bltin.h: 1.15
bin/sh/cd.c: 1.49-1.50
bin/sh/error.c: 1.40
bin/sh/eval.c: 1.142-1.151
bin/sh/exec.c: 1.49-1.51
bin/sh/exec.h: 1.26
bin/sh/expand.c: 1.113-1.119
bin/sh/expand.h: 1.23
bin/sh/histedit.c: 1.49-1.52
bin/sh/input.c: 1.57-1.60
bin/sh/input.h: 1.19-1.20
bin/sh/jobs.c: 1.86-1.87
bin/sh/main.c: 1.71-1.72
bin/sh/memalloc.c: 1.30
bin/sh/memalloc.h: 1.17
bin/sh/mknodenames.sh: 1.4
bin/sh/mkoptions.sh: 1.3-1.4
bin/sh/myhistedit.h: 1.12-1.13
bin/sh/nodetypes: 1.16-1.18
bin/sh/option.list: 1.3-1.5
bin/sh/parser.c: 1.133-1.141
bin/sh/parser.h: 1.22-1.23
bin/sh/redir.c: 1.58
bin/sh/redir.h: 1.24
bin/sh/sh.1: 1.149-1.159
bin/sh/shell.h: 1.24
bin/sh/show.c: 1.43-1.47
bin/sh/show.h: 1.11
bin/sh/syntax.c: 1.4
bin/sh/syntax.h: 1.8
bin/sh/trap.c: 1.41
bin/sh/var.c: 1.56-1.65
bin/sh/var.h: 1.29-1.35
An initial attempt at implementing LINENO to meet the specs.
Aside from one problem (not too hard to fix if it was ever needed) this version
does about as well as most other shell implementations when expanding
$((LINENO)) and better for ${LINENO} as it retains the "LINENO hack" for the
latter, and that is very accurate.
Unfortunately that means that ${LINENO} and $((LINENO)) do not always produce
the same value when used on the same line (a defect that other shells do not
share - aside from the FreeBSD sh as it is today, where only the LINENO hack
exists and so (like for us before this commit) $((LINENO)) is always either
0, or at least whatever value was last set, perhaps by
LINENO=${LINENO}
which does actually work ... for that one line...)
This could be corrected by simply removing the LINENO hack (look for the string
LINENO in parser.c) in which case ${LINENO} and $((LINENO)) would give the
same (not perfectly accurate) values, as do most other shells.
POSIX requires that LINENO be set before each command, and this implementation
does that fairly literally - except that we only bother before the commands
which actually expand words (for, case and simple commands). Unfortunately
this forgot that expansions also occur in redirects, and the other compound
commands can also have redirects, so if a redirect on one of the other compound
commands wants to use the value of $((LINENO)) as a part of a generated file
name, then it will get an incorrect value. This is the "one problem" above.
(Because the LINENO hack is still enabled, using ${LINENO} works.)
This could be fixed, but as this version of the LINENO implementation is just
for reference purposes (it will be superseded within minutes by a better one)
I won't bother. However should anyone else decide that this is a better choice
(it is probably a smaller implementation, in terms of code & data space then
the replacement, but also I would expect, slower, and definitely less accurate)
this defect is something to bear in mind, and fix.
This version retains the *BSD historical practice that line numbers in functions
(all functions) count from 1 from the start of the function, and elsewhere,
start from 1 from where the shell started reading the input file/stream in
question. In an "eval" expression the line number starts at the line of the
"eval" (and then increases if the input is a multi-line string).
Note: this version is not documented (beyond as much as LINENO was before)
hence this slightly longer than usual commit message.
A better LINENO implementation. This version deletes (well, #if 0's out)
the LINENO hack, and uses the LINENO var for both ${LINENO} and $((LINENO)).
(Code to invert the LINENO hack when required, like when de-compiling the
execution tree to provide the "jobs" command strings, is still included,
that can be deleted when the LINENO hack is completely removed - look for
refs to VSLINENO throughout the code. The var funclinno in parser.c can
also be removed, it is used only for the LINENO hack.)
This version produces accurate results: $((LINENO)) was made as accurate
as the LINENO hack made ${LINENO} which is very good. That's why the
LINENO hack is not yet completely removed, so it can be easily re-enabled.
If you can tell the difference when it is in use, or not in use, then
something has broken (or I managed to miss a case somewhere.)
The way that LINENO works is documented in its own (new) section in the
man page, so nothing more about that, or the new options, etc, here.
This version introduces the possibility of having a "reference" function
associated with a variable, which gets called whenever the value of the
variable is required (that's what implements LINENO). There is just
one function pointer however, so any particular variable gets at most
one of the set function (as used for PATH, etc) or the reference function.
The VFUNCREF bit in the var flags indicates which func the variable in
question uses (if any - the func ptr, as before, can be NULL).
I would not call the results of this perfect yet, but it is close.
Unbreak (at least) i386 build .... I have no idea why this built for me on
amd64 (problem was missing prototype for snprintf witout <stdio.h>)
While here, add some (DEBUG mode only) tracing that proved useful in
solving another problem.
Set the line number before expanding args, not after. As the line_number
would have usually been set earlier, this change is mostly an effective
no-op, but it is better this way (just in case) - not observed to have
caused any problems.
Undo some over agressive fixes for a (pre-commit) bug that did not
need these changes to be fixed - and these cause problems in another
absurd use case. Either of these issues is unlikely to be seen by
anyone who isn't an idiot masochist...
PR bin/52280
removescapes_nl in expari() even when not quoted,
CRTNONL's appear regardless of quoting (unlike CTLESC).
New sentence, new line. Whitespace.
Improve the (new) LINENO section, markup changes (with thanks to wiz@ for
assistace) and some better wording in a few placed.
I am an idiot... revert the previous unintended commit.
Remove some left over baggage from the LINENO v1 implementation that
didn't get removed with v2, and should have. This would have had
(I think, without having tested it) one very minor effect on the way
LINENO worked in the v2 implementation, but my guess is it would have
taken a long time before anyone noticed...
Correct spelling in comments of DEBUG only code...
(Perhaps) temporary fix to pkgtools (cwrappers) build (configure).
Expanding `` containing \ \n sequences looks to have been giving
problems. I don't think this is the correct fix, but it will do
no worse harm than (perhaps) incorrectly calculating LINENO in this
kind of (rare) circumstance. I'll look and see if there should be
a better fix later.
s/volatile/const/ -- wonderful how opposites attract like this.
NFC (normal use) - DEBUG only change, when showing empty arg list don't
omit terminating \n.
Free stack memory in a couple of obscure cases where it wasn't
being done (one in probably dead code that is never compiled, the other
in a very rare error case.) Since it is stack memory it wasn't lost
in any case, just held longer than needed.
Many internal memory management type fixes.
PR bin/52302 (core dump with interactive shell, here doc and error
on same line) is fixed. (An old bug.)
echo "$( echo x; for a in $( seq 1000 ); do printf '%s\n'; done; echo y )"
consistently prints 1002 lines (x, 1000 empty ones, then y) as it should
(And you don't want to know what it did before, or why.) (Another old one.)
(Recently added) Problems with ~ expansion fixed (mem management related).
Proper fix for the cwrappers configure problem (which includes the quick
fix that was done earlier, but extends upon that to be correct). (This was
another newly added problem.)
And the really devious (and rare) old bug - if STACKSTRNUL() needs to
allocate a new buffer in which to store the \0, calculate the size of
the string space remaining correctly, unlike when SPUTC() grows the
buffer, there is no actual data being stored in the STACKSTRNUL()
case - the string space remaining was calculated as one byte too few.
That would be harmless, unless the next buffer also filled, in which
case it was assumed that it was really full, not one byte less, meaning
one junk char (a nul, or anything) was being copied into the next (even
bigger buffer) corrupting the data.
Consistent use of stalloc() to allocate a new block of (stack) memory,
and grabstackstr() to claim a block of (stack) memory that had already
been occupied but not claimed as in use. Since grabstackstr is implemented
as just a call to stalloc() this is a no-op change in practice, but makes
it much easier to comprehend what is really happening. Previous code
sometimes used stalloc() when the use case was really for grabstackstr().
Change grabstackstr() to actually use the arg passed to it, instead of
(not much better than) guessing how much space to claim,
More care when using unstalloc()/ungrabstackstr() to return space, and in
particular when the stack must be returned to its previous state, rather than
just returning no-longer needed space, neither of those work. They also don't
work properly if there have been (really, even might have been) any stack mem
allocations since the last stalloc()/grabstackstr(). (If we know there
cannot have been then the alloc/release sequence is kind of pointless.)
To work correctly in general we must use setstackmark()/popstackmark() so
do that when needed. Have those also save/restore the top of stack string
space remaining.
[Aside: for those reading this, the "stack" mentioned is not
in any way related to the thing used for maintaining the C
function call state, ie: the "stack segment" of the program,
but the shell's internal memory management strategy.]
More comments to better explain what is happening in some cases.
Also cleaned up some hopelessly broken DEBUG mode data that were
recently added (no effect on anyone but the poor semi-human attempting
to make sense of it...).
User visible changes:
Proper counting of line numbers when a here document is delimited
by a multi-line end-delimiter, as in
cat << 'REALLY
END'
here doc line 1
here doc line 2
REALLY
END
(which is an obscure case, but nothing says should not work.) The \n
in the end-delimiter of the here doc (the last one) was not incrementing
the line number, which from that point on in the script would be 1 too
low (or more, for end-delimiters with more than one \n in them.)
With tilde expansion:
unset HOME; echo ~
changed to return getpwuid(getuid())->pw_home instead of failing (returning ~)
POSIX says this is unspecified, which makes it difficult for a script to
compensate for being run without HOME set (as in env -i sh script), so
while not able to be used portably, this seems like a useful extension
(and is implemented the same way by some other shells).
Further, with
HOME=; printf %s ~
we now write nothing (which is required by POSIX - which requires ~ to
expand to the value of $HOME if it is set) previously if $HOME (in this
case) or a user's directory in the passwd file (for ~user) were a null
STRING, We failed the ~ expansion and left behind '~' or '~user'.
Changed the long name for the -L option from lineno_fn_relative
to local_lineno as the latter seemed to be marginally more popular,
and perhaps more importantly, is the same length as the peviously
existing quietprofile option, which means the man page indentation
for the list of options can return to (about) what it was before...
(That is, less indented, which means more data/line, which means less
lines of man page - a good thing!)
Cosmetic changes to variable flags - make their values more suited
to my delicate sensibilities... (NFC).
Arrange not to barf (ever) if some turkey makes _ readonly. Do this
by adding a VNOERROR flag that causes errors in var setting to be
ignored (intended use is only for internal shell var setting, like of "_").
(nb: invalid var name errors ignore this flag, but those should never
occur on a var set by the shell itself.)
From FreeBSD: don't simply discard memory if a variable is not set for
any reason (including because it is readonly) if the var's value had
been malloc'd. Free it instead...
NFC - DEBUG changes, update this to new TRACE method.
KNF - white space and comment formatting.
NFC - DEBUG mode only change - convert this to the new TRACE() format.
NFC - DEBUG mode only change - complete a change made earlier (marking
the line number when included in the trace line tag to show whether it
comes from the parser, or the elsewhere as they tend to be quite different).
Initially only one case was changed, while I pondered whether I liked it
or not. Now it is all done... Also when there is a line tag at all,
always include the root/sub-shell indicator character, not only when the
pid is included.
NFC: DEBUG related comment change - catch up with reality.
NFC: DEBUG mode only change. Fix botched cleanup of one TRACE().
"b" more forgiving when sorting options to allow reasonable (and intended)
flexibility in option.list format. Changes nothing for current option.list.
Now that excessive use of STACKSTRNUL has served its purpose (well, accidental
purpose) in exposing the bug in its implementation, go back to not using
it when not needed for DEBUG TRACE purposes. This change should have no
practical effect on either a DEBUG shell (where the STACKSTRNUL() calls
remain) or a non DEBUG shell where they are not needed.
Correct the initial line number used for processing -c arg strings.
(It was inheriting the value from end of profile file processing) - I didn't
notice before as I usually test with empty or no profile files to avoid
complications. Trivial change which should have very limited impact.
Fix from FreeBSD (applied there in July 2008...)
Don't dump core with input like sh -c 'x=; echo >&$x' - that is where
the word after a >& or <& redirect expands to nothing at all.
Another fix from FreeBSD (this one from April 2009).
When processing a string (as in eval, trap, or sh -c) don't allow
trailing \n's to destroy the exit status of the last command executed.
That is:
sh -c 'false
'
echo $?
should produce 1, not 0.
It is amazing what nonsense appears to work sometimes... (all my nonsense too!)
Two bugs here, one benign because of the way the script is used.
The other hidden by NetBSD's sort being stable, and the data not really
requiring sorting at all...
So as it happens these fixes change nothing, but they are needed anyway.
(The contents of the generated file are only used in DEBUG shells, so
this is really even less important than it seems.)
Another ancient (highly improbable) bug bites the dust. This one
caused by incorrect macro usage (ie: using the wrong one) which has
been in the sources since version 1.1 (ie: forever).
Like the previous (STACKSTRNUL) bug, the probability of this one
actually occurring has been infinitesimal but the LINENO code increases
that to infinitesimal and a smidgen... (or a few, depending upon usage).
Still, apparently that was enough, Kamil Rytarowski discovered that the
zsh configure script (damn competition!) managed to trigger this problem.
source .editrc after we initialize so that commands persist!
Make arg parsing in kill POSIX compatible with POSIX (XBD 2.12) by
parsing the way getopt(3) would, if only it could handle the (required)
-signumber and -signame options. This adds two "features" to kill,
-ssigname and -lstatus now work (ie: one word with all of the '-', the
option letter, and its value) and "--" also now works (kill -- -pid1 pid2
will not attempt to send the pid1 signal to pid2, but rather SIGTERM
to the pid1 process group and pid2). It is still the case that (apart
from --) at most 1 option is permitted (-l, -s, -signame, or -signumber.)
Note that we now have an ambiguity, -sname might mean "-s name" or
send the signal "sname" - if one of those turns out to be valid, that
will be accepted, otherwise the error message will indicate that "sname"
is not a valid signal name, not that "name" is not. Keeping the "-s"
and signal name as separate words avoids this issue.
Also caution: should someone be weird enough to define a new signal
name (as in the part after SIG) which is almost the same name as an
existing name that starts with 'S' by adding an extra 'S' prepended
(eg: adding a SIGSSYS) then the ambiguity problem becomes much worse.
In that case "kill -ssys" will be resolved in favour of the "-s"
flag being used (the more modern syntax) and would send a SIGSYS, rather
that a SIGSSYS. So don't do that.
While here, switch to using signalname(3) (bye bye NSIG, et. al.), add
some constipation, and show a little pride in formatting the signal names
for "kill -l" (and in the usage when appropriate -- same routine.) Respect
COLUMNS (POSIX XBD 8.3) as primary specification of the width (terminal width,
not number of columns to print) for kill -l, a very small value for COLUMNS
will cause kill -l output to list signals one per line, a very large
value will cause them all to be listed on one line.) (eg: "COLUMNS=1 kill -l")
TODO: the signal printing for "trap -l" and that for "kill -l"
should be switched to use a common routine (for the sh builtin versions.)
All changes of relevance here are to bin/kill - the (minor) changes to bin/sh
are only to properly expose the builtin version of getenv(3) so the builtin
version of kill can use it (ie: make its prototype available.)
Properly support EDITRC - use it as (naming) the file when setting
up libedit, and re-do the config whenever EDITRC is set.
Get rid of workarounds for ancient groff html backend.
Simplify macro usage.
Make one example more like a real world possibility (it still isn't, but
is closer) - though the actual content is irrelevant to the point being made.
Add literal prompt support this allows one to do:
CA="$(printf '\1')"
PS1="${CA}$(tput bold)${CA}\$${CA}$(tput sgr0)${CA} "
Now libedit supports embedded mode switch sequence, improve sh
support for them (adds PSlit variable to set the magic character).
NFC: DEBUG only change - provide an externally visible (to the DEBUG sh
internals) interface to one of the internal (private to trace code) functions
Include redirections in trace output from "set -x"
Implement PS1, PS2 and PS4 expansions (variable expansions, arithmetic
expansions, and if enabled by the promptcmds option, command substitutions.)
Implement a bunch of new shell environment variables. many mostly useful
in prompts when expanded at prompt time, but all available for general use.
Many of the new ones are not available in SMALL shells (they work as normal
if assigned, but the shell does not set or use them - and there is no magic
in a SMALL shell (usually for install media.))
Omnibus manual update for prompt expansions and new variables. Throw in
some random cleanups as a bonus.
Correct a markup typo (why did I not see this before the prev commit??)
Sort options (our default is 0..9AaBbZz).
Fix markup problems and a typo.
Make $- list flags in the same order they appear in sh(1)
Do a better job of detecting the error in pkgsrc/devel/libbson-1.6.3's
configure script, ie: $(( which is intended to be a sub-shell in a
command substitution, but is an arith subst instead, it needs to be
written $( ( to do as intended. Instead of just blindly carrying on to
find the missing )) somewhere, anywhere, give up as soon as we have seen
an unbalanced ')' that isn't immediately followed by another ')' which
in a valid arith subst it always would be.
While here, there has been a comment in the code for quite a while noting a
difference in the standard between the text descr & grammar when it comes to
the syntax of case statements. Add more comments to explain why parsing it
as we do is in fact definitely the correct way (ie: the grammar wins arguments
like this...).
DEBUG and white space changes only. Convert TRACE() calls for DEBUg mode
to the new style. NFC (when not debugging sh).
Mostly DEBUG and white space changes. Convert DEEBUG TRACE() calls to
the new format. Also #if 0 a function definition that is used nowhere.
While here, change the function of pushfile() slightly - it now sets
the buf pointer in the top (new) input descriptor to NULL, instead of
simply leaving it - code that needs a buffer always (before and after)
must malloc() one and assign it after the call. But code which does not
(which will be reading from a string or similar) now does not have to
explicitly set it to NULL (cleaner interface.) NFC intended (or observed.)
DEBUG changes: convert DEBUG TRACE() calls to new format.
ALso, cause exec failures to always cause the shell to exit with
status 126 or 127, whatever the cause. 127 is intended for lookup
failures (and is used that way), 126 is used for anything else that
goes wrong (as in several other shells.) We no longer use 2 (more easily
confused with an exit status of the command exec'd) for shell exec failures.
DEBUG only changes. Convert the TRACE() calls in the remaining files
that still used it to the new format. NFC.
Fix a reference after free (and consequent nonsense diagnostic for
attempts to set readonly variables) I added in 1.60 by incompletely
copying the FreeBSD fix for the lost memory issue.
 1.30.6.3  21-Apr-2020  martin Ooops, restore accidently removed files from merge mishap
 1.30.6.2  21-Apr-2020  martin Sync with HEAD
 1.30.6.1  10-Jun-2019  christos Sync with HEAD
 1.30.4.2  06-Sep-2018  pgoyette Sync with HEAD

Resolve a couple of conflicts (result of the uimin/uimax changes)
 1.30.4.1  28-Jul-2018  pgoyette Sync with HEAD
 1.33.2.2  09-May-2025  martin Pull up following revision(s) (requested by kre in ticket #1948):

bin/sh/memalloc.c: revision 1.40

PR bin/59395 Remove some dead code.

Back in Nov 2021, the way here docs were implemented was changed
to fix problem report 53550 and this code can no longer ever
be executed (it is impossible without reintroducing the 53550
problems), so time for it to go.

This will make no functional difference to sh in HEAD,
and wouldn't in -10, if this were worth pulling up there (it isn't).
However, in -9 this code still runs (in the relatively rare cases
that it applies), but is broken, leading to the problem in 59395.

Removing this code, which is just an optimisation, will correct
that problem (for current releases only -9 is affected).
PR bin/59395
 1.33.2.1  06-Nov-2021  martin Pull up following revision(s) (requested by kre in ticket #1371):

bin/sh/main.c: revision 1.87
bin/sh/main.c: revision 1.88
bin/sh/memalloc.h: revision 1.20
bin/sh/sh.1: revision 1.235
bin/sh/memalloc.c: revision 1.34
bin/sh/memalloc.c: revision 1.35
bin/sh/memalloc.h: revision 1.19
bin/sh/shell.h: revision 1.31
bin/sh/options.c: revision 1.56

PR bin/56464

After almost 30 years, finally do the right thing and read $HOME/.profile
rather than .profile in the initial directory (it was that way in version
1.1 ...) All other ash descendants seem to have fixed this long ago.
While here, copy a feature from FreeBSD which allows "set +p" (if a
shell run by a setuid process with the -p flag is privileged) to reset
the privileges. Once done (the set +p) it cannot be undone (a later
set -p sets the 'p' flag, but that's all it does) - that just becomes a
one bit storage location.

We do this, as (also copying from FreeBSD, and because it is the right
thing to do) we don't run .profile in a privileged shell - FreeBSD run
/etc/suid_profile in that case (not a good name, it also applies to setgid
shells) but I see no real need for that, we run /etc/profile in any case,
anything that would go in /etc/suid_profile can just go in /etc/profile
instead (with suitable guards so the commands only run in priv'd shells).

One or two minor DEBUG mode changes (notably having priv'd shells identify
themselves in the DEBUG trace) and sh.1 changes with doc of the "set +p"
change, the effect that has on $PSc and a few other wording tweaks.

XXX pullup -9 (not -8, this isn't worth it for the short lifetime
that has left - if it took 28+ years for anyone to notice this, it
cannot be having all that much effect).

Use a type-correct end marker for strstrcat() rather than NULL, as
for a function with unknown number & types of args, the compiler isn't
able to automatically convert to the correct type. Issue pointed out
in off list e-mail by Rolland Illig ... Thanks.

The first arg (pointer to where to put length of result) is of a known
type, so doesn't have the same issue - we can keep using NULL for that
one when the length isn't needed.
Also, make sure to return a correctly null terminated null string in
the (absurd) case that there are no non-null args to strstrcat() (though
there are much better ways to generate "" on the stack). Since there is
currently just one call in the code, and it has real string args, this
isn't an issue for now, but who knows, some day.

NFCI - if there is any real change, then it is a change that is required.

XXX pullup -9 (together with the previous changes)
 1.39.2.1  02-Aug-2025  perseant Sync with HEAD

RSS XML Feed