Otherwise `AGRS` and `program_arguments` remain allocated/unfreed in the
early (extremely unlikely) pledge(2) failure case.
Move their allocation before jq_init(), the first case of jumping to
`out` where they are cleaned up, where it also seems to logically fit
better than above between function entry, locale setup and OpenBSD
specific pledge.
Use pledge(2)[0] to limit jq(1) to reading files.
It does not change files and only writes to standard output/error.
It never deals with TTY, network, process management or other subsystems.
This is to reduce jq's attack surface and potential damage.
OpenBSD is carrying a local patch[1] in its official jq port/package
since 2016. An improved version:
- drop no longer needed "getpw" promise
f1c4947 "Avoid getpwuid for static linking" removed getpwuid(3) usage
- pledge before jq_init() to simplify the error path
- use perror(3) to print errno(2)
No behaviour change in tests or real world usage observed on
OpenBSD/amd64 7.4.
0: https://man.openbsd.org/pledge.2
1: https://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/textproc/jq/patches/patch-main_c
Klemens Nanni