The system curses library can handle terminal size changes with
SIGWINCH without asking system calls to restart, which effectively
stops system calls with -1 and EINTR. An example is ncurses on
Linux systems.
One of these system calls is waitpid. While waiting for the lsof child
to complete, a badly timed SIGWINCH can interrupt the waitpid call,
effectively never clearing the state of the child, keeping the zombie
until htop exits.
Proof of Concept:
#include <unistd.h>
int main(void) {
close(1); close(2);
sleep(5);
return 0;
}
Compile this as a replacement "lsof" and put it into your path. Make
sure that it's called instead of the real lsof.
Press "l" to list open files and resize your terminal within the next
5 seconds. You will see that a zombie process is kept by htop when the
timeout finishes.
- Remove local types and function from header file
- Reduce OpenFiles_Data to neccessary size
- Print file access mode (r/w/u)
- Fix memory leak on consecutive items without an intermediate file item:
==15257==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 120 byte(s) in 12 object(s) allocated from:
#0 0x48c864 in strdup (htop/htop+0x48c864)
#1 0x542f68 in xStrdup htop/XAlloc.c:71:17
#2 0x50e225 in OpenFilesScreen_getProcessData htop/OpenFilesScreen.c:112:25
#3 0x50cd17 in OpenFilesScreen_scan htop/OpenFilesScreen.c:141:35
#4 0x4fd3eb in InfoScreen_run htop/InfoScreen.c:81:35
#5 0x4d58bb in actionLsof htop/Action.c:361:4
#6 0x501766 in MainPanel_eventHandler htop/MainPanel.c:80:19
#7 0x5289fa in ScreenManager_run htop/ScreenManager.c:227:19
#8 0x4f748e in main htop/htop.c:300:4
#9 0x7ff73e0d8cc9 in __libc_start_main csu/../csu/libc-start.c:308:16
SUMMARY: AddressSanitizer: 120 byte(s) leaked in 12 allocation(s).
Reasoning:
- implementation was unsound -- broke down when I added a fairly
basic macro definition expanding to a struct initializer in a *.c
file.
- made it way too easy (e.g. via otherwise totally innocuous git
commands) to end up with timestamps such that it always ran
MakeHeader.py but never used its output, leading to overbuild noise
when running what should be a null 'make'.
- but mostly: it's just an awkward way of dealing with C code.
* Dynamically adjust the size of line reads.
* Remove some more uses of fgets with arbitrary sizes.
* Fix reading of lines and width of n column.
Fixes#514.
* Performance improvements
* Support for splitting CPU meters into two or four columns
(thanks to Wim Heirman)
* Switch from PLPA, which is now deprecated, to HWLOC.
* Bring back support for native Linux sched_setaffinity,
so we don't have to use HWLOC where we don't need to.
* Support for typing in user names and column fields in selection panels.
Explorer09