RFR: 8298730: Refactor subsystem_file_line_contents and add docs and tests [v2]

[Johan Sjölen]

On Wed, 14 Dec 2022 10:51:39 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

>> Johan Sjölen has updated the pull request incrementally with seven additional commits since the last revision:
>> 
>>  - Split into single-line and multiple-line tests
>>  - Rename tests
>>  - Revert
>>  - Specify buffer limit in format specifier
>>  - Fix log string
>>  - Allow other whitespace than space, add test for \t
>>  - More tests, including JULONG and JLONG.
>
> src/hotspot/os/linux/cgroupV1Subsystem_linux.cpp line 287:
> 
>> 285: char* CgroupV1Subsystem::pids_max_val() {
>> 286:   GET_CONTAINER_INFO_CPTR(cptr, _pids, "/pids.max",
>> 287:                      "Maximum number of tasks is: %s", "%s", pidsmax, 1024);
> 
> To keep the format specifiers in sync, please use `%1023s` over `%s` here instead.

Fixed.

-------------

PR: https://git.openjdk.org/jdk/pull/11667