automatically it is possible wait4(2) returns -1 and sets
errno = ECHILD if there were forked children. A user can
set such signal handler e.g. via ``trap "" 20'', see a PR
for the test case. Deal with this case and mark a job as
JOBDONE.
PR: bin/90334
Submitted by: bde
MFC after: 4 weeks
This makes a difference for the trap builtin, where after "trap '' 0" we
printed "trap -- quit". This is wrong, because an empty action means to reset
the action to the default. A side effect of this commit is that empty
variables are now printed as "variable=''" instead of just "variable=".
itself and its children. Instead of calling times() (as implied by POSIX) this
implementation directly calls getrusage() to get the times because this is more
convenient.
set +o can be used to reload previous settings, for this to work disabled
options must be printed as well or otherwise options that were set in the mean
time won't be turned off.
To avoid an excessively long output line I formatted the output to print only
six options per line.
Submitted by: Jilles Tjoelker
PR: 73500
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
termination with set -e if a command fails in a loop body inside a function
with an explicitely tested exit status, eg
f() {
for i in 1 2 3; do
false
done
}
f || true
Briefly reviewed by: cracauer
two cases of unwanted termination with set -e:
* if-commands containing several commands separated by semicolons, eg
if false; false; then [...]
* functions with an explicitely tested exit status that contain a failing
command which is not the last one, eg
f() {
false
false
}
f || true
PR: 77067, 85267
Briefly reviewed by: cracauer
and linting procedure:
1. Remove useless sub-expression:
- if (*start || (!ifsspc && start > string && (nulonly || 1))) {
+ if (*start || (!ifsspc && start > string)) {
The sub-expression "(nulonly || 1)" always evaluates to true and
according to CVS logs seems to be just a left-over from some
debugging and introduced by accident. Removing the sub-expression
doesn't change semantics and a code inspection showed that the
variable "nulonly" is also not necessary here in any way (and the
expression would require fixing instead of removing).
2. Remove dead code:
- if (backslash && c == '\\') {
- if (read(STDIN_FILENO, &c, 1) != 1) {
- status = 1;
- break;
- }
- STPUTC(c, p);
- } else if (ap[1] != NULL && strchr(ifs, c) != NULL) {
+ if (ap[1] != NULL && strchr(ifs, c) != NULL) {
Inspection of the control and data flow showed that variable
"backslash" is always false (0) when the "if"-expression is
evaluated, hence the whole block is effectively dead code.
Additionally, the skipping of characters after a backslash is already
performed correctly a few lines above, so this code is also not
needed at all. According to the CVS logs and the ASH 0.2 sources,
this code existed in this way already since its early days.
3. Cleanup Style:
- ! trap[signo][0] == '\0' &&
+ ! (trap[signo][0] == '\0') &&
The expression wants to ensure the trap is not assigned the empty
string. But the "!" operator has higher precedence than "==", so the
comparison should be put into parenthesis to form the intended way of
expression. Nevertheless the code was effectively not really broken
as both particular NUL comparisons are semantically equal, of course.
But the parenthesized version is a lot more intuitive.
4. Remove shadowing variable declaration:
- char *q;
The declaration of symbol "q" hides another identical declaration of
"q" in the same context. As the other "q" is already reused multiple
times and also can be reused again without negative side-effects,
just remove the shadowing declaration.
5. Just small cosmetics:
- if (ifsset() != 0)
+ if (ifsset())
The ifsset() macro is already coded by returning the boolean result
of a comparison operator, so no need to compare this boolean result
again against a numerical value. This also aligns the macros usage to
the remaining existing code.
Reviewed by: stefanf@
