From 5f69d4a1292c2766cc70074478aab17258b8f149 Mon Sep 17 00:00:00 2001
From: Lucas <lucas@sexy.is>
Date: Sun, 15 Aug 2021 04:10:36 +0000
Subject: 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
---
 makefile | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

(limited to 'makefile')

diff --git a/makefile b/makefile
index d19ec24d..40cb6787 100644
--- a/makefile
+++ b/makefile
@@ -90,12 +90,12 @@ prosody.cfg.lua.install: prosody.cfg.lua.dist
 	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
-- 
cgit v1.2.3