When checking the status from waitpid on a kill -STOP <child_pid> WIFSIGNALED returns true #472
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📌 Commit 9f6f374 has been approved by |
When checking the status from waitpid on a kill -STOP <child_pid> WIFSIGNALED returns true Currently in WIFSIGNALED rust is doing: (status & 0x7f) + 1 where status is i32 As defined in /usr/include/x86_64-linux-gnu/bits/waitstatus.h #define __WIFSIGNALED(status) \ (((signed char) (((status) & 0x7f) + 1) >> 1) > 0) Here is an example of the issue: http://paste2.org/fXc8BxJ0 Run it, and it'll print the child pid then: kill -STOP <child_pid> Expect: Stopped by signal print statement Results: Killed by signal print statement Using the i32, it wont overflow leaving you with 128 returning true, using the waitstatus define you'll end up with -64 (since it shifts 1 right) which would return false. Though the C version shifts right once not really sure *why* but theres most likely a reason somewhere. For the fix, just cast to i8 (signed char pretty much) as the C version is doing. RUNNING ALL TESTS PASSED 7356 tests
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☀️ Test successful - status-appveyor, status-travis |
Currently in WIFSIGNALED rust is doing:
(status & 0x7f) + 1
where status is i32
As defined in /usr/include/x86_64-linux-gnu/bits/waitstatus.h
#define __WIFSIGNALED(status)
(((signed char) (((status) & 0x7f) + 1) >> 1) > 0)
Here is an example of the issue:
http://paste2.org/fXc8BxJ0
Run it, and it'll print the child pid then:
kill -STOP <child_pid>
Expect:
Stopped by signal print statement
Results:
Killed by signal print statement
Using the i32, it wont overflow leaving you with 128 returning true, using the waitstatus define you'll end up with -64 (since it shifts 1 right) which would return false. Though the C version shifts right once not really sure why but theres most likely a reason somewhere.
For the fix, just cast to i8 (signed char pretty much) as the C version is doing.
RUNNING ALL TESTS
PASSED 7356 tests