- add missing assertions,
- use GREEDY_REALLOC() at one more place,
- etc.
Before:
```
$ sudo time valgrind --leak-check=full ./systemd-hwdb update
==112572== Memcheck, a memory error detector
==112572== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al.
==112572== Using Valgrind-3.23.0 and LibVEX; rerun with -h for copyright info
==112572== Command: ./systemd-hwdb update
==112572==
==112572==
==112572== HEAP SUMMARY:
==112572== in use at exit: 0 bytes in 0 blocks
==112572== total heap usage: 1,320,113 allocs, 1,320,113 frees, 70,614,501 bytes allocated
==112572==
==112572== All heap blocks were freed -- no leaks are possible
==112572==
==112572== For lists of detected and suppressed errors, rerun with: -s
==112572== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
21.94user 0.19system 0:22.23elapsed 99%CPU (0avgtext+0avgdata 229876maxresident)k
0inputs+25264outputs (0major+57275minor)pagefaults 0swaps
```
After:
```
$ sudo time valgrind --leak-check=full ./systemd-hwdb update
[sudo] password for watanabe:
==114732== Memcheck, a memory error detector
==114732== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al.
==114732== Using Valgrind-3.23.0 and LibVEX; rerun with -h for copyright info
==114732== Command: ./systemd-hwdb update
==114732==
==114732==
==114732== HEAP SUMMARY:
==114732== in use at exit: 0 bytes in 0 blocks
==114732== total heap usage: 1,276,406 allocs, 1,276,406 frees, 68,500,491 bytes allocated
==114732==
==114732== All heap blocks were freed -- no leaks are possible
==114732==
==114732== For lists of detected and suppressed errors, rerun with: -s
==114732== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
21.91user 0.24system 0:22.26elapsed 99%CPU (0avgtext+0avgdata 233584maxresident)k
0inputs+25168outputs (0major+58237minor)pagefaults 0swaps
```
This allows us to reserve a bunch of capacity ahead of time,
improving the performance of hwdb significantly thanks to not
having to reallocate so many times.
Before:
```
$ sudo time valgrind --leak-check=full ./systemd-hwdb update
==113297== Memcheck, a memory error detector
==113297== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al.
==113297== Using Valgrind-3.23.0 and LibVEX; rerun with -h for copyright info
==113297== Command: ./systemd-hwdb update
==113297==
==113297==
==113297== HEAP SUMMARY:
==113297== in use at exit: 0 bytes in 0 blocks
==113297== total heap usage: 1,412,640 allocs, 1,412,640 frees, 117,920,009,195 bytes allocated
==113297==
==113297== All heap blocks were freed -- no leaks are possible
==113297==
==113297== For lists of detected and suppressed errors, rerun with: -s
==113297== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
132.44user 21.15system 2:35.61elapsed 98%CPU (0avgtext+0avgdata 228560maxresident)k
0inputs+25296outputs (0major+6886930minor)pagefaults 0swaps
```
After:
```
$ sudo time valgrind --leak-check=full ./systemd-hwdb update
==112572== Memcheck, a memory error detector
==112572== Copyright (C) 2002-2024, and GNU GPL'd, by Julian Seward et al.
==112572== Using Valgrind-3.23.0 and LibVEX; rerun with -h for copyright info
==112572== Command: ./systemd-hwdb update
==112572==
==112572==
==112572== HEAP SUMMARY:
==112572== in use at exit: 0 bytes in 0 blocks
==112572== total heap usage: 1,320,113 allocs, 1,320,113 frees, 70,614,501 bytes allocated
==112572==
==112572== All heap blocks were freed -- no leaks are possible
==112572==
==112572== For lists of detected and suppressed errors, rerun with: -s
==112572== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
21.94user 0.19system 0:22.23elapsed 99%CPU (0avgtext+0avgdata 229876maxresident)k
0inputs+25264outputs (0major+57275minor)pagefaults 0swaps
```
Co-authored-by: Yu Watanabe <watanabe.yu+github@gmail.com>
I started working on this because I wanted to change how
DEFINE_TRIVIAL_CLEANUP_FUNC is defined. Even independently of that change, it's
nice to make make things more consistent and predictable.
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
Not that it matters much, but it seems cleaner to also count those
inputs, even if they do not consume extra storage space.
The test is extended to include an empty input and counts in the test are
adjusted to include it.
Commit 82501b3fc added an early break when a terminal node is found to
incorrect place -- before setting c. This caused trie to be built that
does not correspond to what it points to in buffer, causing incorrect
deduplications:
# cat /etc/udev/rules.d/99-bug.rules
ENV{FOO}=="0"
ENV{xx0}=="BAR"
ENV{BAZ}=="00"
# udevadm test
* RULE /etc/udev/rules.d/99-bug.rules:1, token: 0, count: 2, label: ''
M ENV match 'FOO' '0'(plain)
* RULE /etc/udev/rules.d/99-bug.rules:2, token: 2, count: 2, label: ''
M ENV match 'xx0' 'BAR'(plain)
* RULE /etc/udev/rules.d/99-bug.rules:3, token: 4, count: 2, label: ''
M ENV match 'BAZ' 'x0'(plain)
* END
The addition of "xx0" following "0" will cause a trie like this to be
created:
c=\0
c=0 "0"
c=0 "xx0" <-- note the c is incorrect here, causing "00" to be
c=O "FOO" deduplicated to it
c=R "BAR"
This in effect caused the usb_modeswitch rule for Huawei modems to never
match and this never be switched to serial mode from mass storage.
Throughout the tree there's spurious use of spaces separating ++ and --
operators from their respective operands. Make ++ and -- operator
consistent with the majority of existing uses; discard the spaces.