makefile: fix prosody.version target
POSIX is quite explicit regarding the precedence of AND-OR lists [0]:
> The operators "&&" and "||" shall have equal precedence and shall be
> evaluated with left associativity. For example, both of the following
> commands write solely `bar` to standard output:
> false && echo foo || echo bar
> true || echo foo && echo bar
Given that, `prosody.version` target behaves as
((((((test -f prosody.release && cp ...) ||
test -f ...) &&
sed ...) ||
test -f ...) &&
hexdump ...) ||
echo unknown > $@)
In the case of release tarballs, `prosody.release` does exist, so the
first AND pair is executed. Given that it's successful, then the first
`test -f` in the OR pair is ignored, and instead the `sed` in the AND
pair is executed. `sed` success, as `.hg_archival.txt` exists, making
the second `test -f` in the OR pair ignored, and `hexdump` in the AND
pair is executed. Now, given that `.hg` doesn't exist, it fails, so the
last `echo` is run, overwriting `prosody.version` with `unknown`.
This can be worked around placing `()` around the AND pairs. Decided to use
conditionals instead, as I think they better communicate the intention
of the block.
[0]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_03
--- a/makefile Tue Jul 06 08:18:28 2021 +0100
+++ b/makefile Sun Aug 15 04:10:36 2021 +0000
@@ -90,12 +90,12 @@
sed 's|certs/|$(INSTALLEDCONFIG)/certs/|' prosody.cfg.lua.dist > $@
prosody.version:
- test -f prosody.release && \
- cp prosody.release $@ || \
- test -f .hg_archival.txt && \
- sed -n 's/^node: \(............\).*/\1/p' .hg_archival.txt > $@ || \
- test -f .hg/dirstate && \
- hexdump -n6 -e'6/1 "%02x"' .hg/dirstate > $@ || \
- echo unknown > $@
-
-
+ if [ -f prosody.release ]; then \
+ cp prosody.release $@; \
+ elif [ -f .hg_archival.txt ]; then \
+ sed -n 's/^node: \(............\).*/\1/p' .hg_archival.txt > $@; \
+ elif [ -f .hg/dirstate ]; then \
+ hexdump -n6 -e'6/1 "%02x"' .hg/dirstate > $@; \
+ else \
+ echo unknown > $@; \
+ fi