The linked list of stack marks may cause problems if the allocation stack is
used between an exception and a higher-level popstackmark(), as it may then
touch a stack mark that is local to a function which has returned.
Also, the adjustment compares to a pointer passed to realloc(), which is
undefined behaviour.
Instead of adjusting stack marks when reallocating stack blocks, ensure that
such an adjustment is never necessary by fixing a small piece of memory in
place at a stack mark. This also simplifies the code.
To avoid the problems reported in bin/175922, it remains necessary to call
setstackmark() after popstackmark() if the stack mark remains in use.
It now passes WARNS=7 with clang on i386.
GCC 4.2.1 does not understand setjmp() properly so will always trigger
-Wuninitialized. I will not add the volatile keywords to suppress this.
Maintain a pointer to the end of the stack string area instead of how much
space is left. This simplifies the macros in memalloc.h. The places where
the new variable must be updated are only where the memory area is created,
destroyed or resized.
The herefd hack wrote out partial here documents while expanding them. It
seems unnecessary complication given that other expansions just allocate
memory. It causes bugs because the stack is also used for intermediate
results such as arithmetic expressions. Such places should disable herefd
for the duration but not all of them do, and I prefer removing the need for
disabling herefd to disabling it everywhere needed.
Here documents larger than 1024 bytes will use a bit more CPU time and
memory.
Additionally this allows a later change to expand here documents in the
current shell environment. (This is faster for small here documents but also
changes behaviour.)
Obtained from: dash
* Prefer one CHECKSTRSPACE with multiple USTPUTC to multiple STPUTC.
* Add STPUTS macro (based on function) and use it instead of loops that add
nul-terminated strings to the stack string.
No functional change is intended, but code size is about 1K less on i386.
immediately written into the stack after the call. Instead let the caller
manage the "space left".
Previously, growstackstr()'s assumption causes problems with STACKSTRNUL()
where we want to be able to turn a stack into a C string, and later
pretend the NUL is not there.
This fixes a bug in STACKSTRNUL() (that grew the stack) where:
1. STADJUST() called after a STACKSTRNUL() results in an improper adjust.
This can be seen in ${var%pattern} and ${var%%pattern} evaluation.
2. Memory leak in STPUTC() called after a STACKSTRNUL().
Reviewed by: jilles
ckrealloc and ckfree (added), respectively. sh jumps out of the signal handler
using longjmp which is obviously a bad idea during malloc calls.
Note: I think there is still a small race here because volatile sig_atomic_t
only guarantees atomic reads and writes while we're doing increments and
decrements.
Protect a setmode call with INT{ON,OFF} as it calls malloc internally.
PR: 45478
Patch from: Nate Eldredge
- Removed dead declarations
- Made objects that should have been declared as static, static.
The changes use STATIC instead of static, following the existing
convention in the rest of the code.
Approved by: schweikh (mentor)
MFC after: 2 weeks
The initial stack_block is staticly allocated and will be aligned
according to the alignment requirements of pointers, which does not
necessarily match the alignment enforced by ALIGN. To solve this a
more involved change is required: remove the static initial stack
and deal with an initial condition of not having a stack at all. This
change is therefore more risky than the previous ones, but unavoidable
(other than not using the platform default alignment).
Discussed with: tjr
Approved and reviewed by: tjr
Tested on: alpha, i386, ia64 and sparc64
The problem with the previous attempt, as noticed by Marcel, was that
stacknxt was being aligned to a pointer boundary instead of an
ALIGNBYTES + 1 boundary, which broke sparc64.
using the alignment from sys/param.h (16) instead of the alignment
from machdep.h (8) tickled a nasty bug in the memory allocator that I
haven't been able to track down yet.
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)
{
...
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().
PR: bin/19983
Submitted by: Tor.Egge@fast.no
Reviewed by: Gerald Pfeifer <pfeifer@dbai.tuwien.ac.at>
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.
multiple times when performing nested variable expansion, and
preserve some quoting information in order to avoid removing
apparently empty expansion result.
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.
face of aliases. Note, bash doesn't do aliases while running scripts, but
"real" ksh does..
Also:
Reduce redundant .Nm macros in (unused) bltin/echo.1
nuke error2, it's hardly used.
More -Wall cleanups
dont do certain history operations if NO_HISTORY defined
handle quad_t's from resource limits
Submitted by: Steve Price <sprice@hiwaay.net> (minor tweaks by me)
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
