build: Replace `which` with `command -v`

The `which` command is not standard, may not exist on the build host,
or may not behave as expected by the build system. It is recommended
to use `command -v` to find out if a command exist and have its path,
and it's part of a POSIX shell standard (at least, it seems to be
mandatory since IEEE Std 1003.1-2008, but was optional before).

Fixes: c8a8645f1efe ("xen/build: Automatically locate a suitable python interpreter")
Fixes: 3b47bcdb6d38 ("xen/build: Use a distro version of figlet")
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: f93629b18b528a5ab1b1092949c5420069c7226c
master date: 2024-02-19 12:45:48 +0100

diff --git a/xen/Makefile b/xen/Makefile
index dd0b004e1cfbab3f0145594d2aa1326c7151d7ae..7ea13a67912cb66edf9004dcc86c6c65b1432693 100644 (file)
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -25,8 +25,8 @@ export XEN_BUILD_HOST := $(shell hostname)
 endif
 
 # Best effort attempt to find a python interpreter, defaulting to Python 3 if
-# available.  Fall back to just `python` if `which` is nowhere to be found.
-PYTHON_INTERPRETER     := $(word 1,$(shell which python3 python python2 2>/dev/null) python)
+# available.  Fall back to just `python`.
+PYTHON_INTERPRETER     := $(word 1,$(shell command -v python3 || command -v python || command -v python2) python)
 export PYTHON          ?= $(PYTHON_INTERPRETER)
 
 export CHECKPOLICY     ?= checkpolicy

diff --git a/xen/build.mk b/xen/build.mk
index 9ecb104f1e0c40ab27edf6e6854f7cd5c5dfee00..b489f77b7c195a117dfc6de61ecf2deffab39ac4 100644 (file)
--- a/xen/build.mk
+++ b/xen/build.mk
@@ -1,6 +1,6 @@
 quiet_cmd_banner = BANNER  $@
 define cmd_banner
-    if which figlet >/dev/null 2>&1 ; then \
+    if command -v figlet >/dev/null 2>&1 ; then \
        echo " Xen $(XEN_FULLVERSION)" | figlet -f $< > $@.tmp; \
     else \
        echo " Xen $(XEN_FULLVERSION)" > $@.tmp; \