+## -*- Autoconf -*-
+## AM_OPTIONAL_AUTOMAKE -- skip `dist-XXX' formats whose tool is absent.
+
+# Copyright (C) 2026 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+
+# AM_OPTIONAL_AUTOMAKE(OPTIONS)
+# -----------------------------
+# OPTIONS: whitespace-separated `dist-XXX' names (AM_INIT_AUTOMAKE
+# spellings) for dist-bzip2/bzip3/xz/lzip/zstd/zip/shar/tarZ. `make
+# dist' builds each archive when its tool is present and skips it
+# otherwise, without failing. Unknown OPTION warns at autoreconf; a
+# tool absent at configure appends no rule; a tool lost afterwards
+# fails the pipeline, which the recipe catches. See bug#81040.
+AC_DEFUN([AM_OPTIONAL_AUTOMAKE],
+[m4_foreach_w([_am_opt_o], [$1],
+ [_AM_OPTIONAL_AUTOMAKE_ONE(_m4_defn([_am_opt_o]))])dnl
+])
+
+
+# _AM_OPTIONAL_AUTOMAKE_ONE(OPT)
+# ------------------------------
+# Dispatch on OPT; unrecognised OPT warns and is ignored.
+AC_DEFUN([_AM_OPTIONAL_AUTOMAKE_ONE],
+[m4_case([$1],
+ [dist-bzip2], [_AM_OPTIONAL_TAR([bzip2], [bzip2], [bz2], [-c])],
+ [dist-bzip3], [_AM_OPTIONAL_TAR([bzip3], [bzip3], [bz3], [-c])],
+ [dist-xz], [_AM_OPTIONAL_TAR([xz], [xz], [xz], [-c])],
+ [dist-lzip], [_AM_OPTIONAL_TAR([lzip], [lzip], [lz], [-c])],
+ [dist-zstd], [_AM_OPTIONAL_TAR([zstd], [zstd], [zst], [-c -q])],
+ [dist-tarZ], [_AM_OPTIONAL_TAR([compress], [compress], [Z], [-c])],
+ [dist-zip], [_AM_OPTIONAL_ZIP()],
+ [dist-shar], [_AM_OPTIONAL_SHAR()],
+ [m4_warn([syntax],
+ [am-optional: unknown option `$1', ignoring it])])dnl
+])
+
+
+# _AM_OPTIONAL_RULE(TAG, VAR, RECIPE, ARTIFACTS)
+# ----------------------------------------------
+# AC_CHECK_PROG for TAG, then once append RECIPE to the top Makefile
+# via AC_CONFIG_COMMANDS (survives config.status reruns) iff configure
+# found the tool. Hooked into dist/dist-all as an extra prerequisite.
+# ARTIFACTS stay out of $(DIST_ARCHIVES), so distcleancheck must remove
+# the copies that the in-tree `make dist' run by `make distcheck' leaves.
+AC_DEFUN([_AM_OPTIONAL_RULE],
+[m4_ifdef([_AM_OPTIONAL_DONE_$1], [],
+ [m4_define([_AM_OPTIONAL_DONE_$1])dnl
+AC_CHECK_PROG([am__optional_$2], [$1], [$1])
+AC_SUBST([am__optional_$2])dnl
+AC_CONFIG_COMMANDS([am--optional-rule-$1],
+[am__optional_mf=
+for am__optional_cand in Makefile GNUmakefile makefile; do
+ if test -f "$am__optional_cand"; then
+ am__optional_mf=$am__optional_cand
+ break
+ fi
+done
+if test -n "$am__optional_mf" && test -n "$am__optional_$2"; then
+ cat >>"$am__optional_mf" <<'_am_opt_rule_eof_'
+
+# Appended by am-optional for dist-$1.
+dist dist-all: am--optional-dist-$1
+distcleancheck: am--optional-rm-$1
+.PHONY: am--optional-dist-$1 am--optional-rm-$1
+$3
+am--optional-rm-$1:
+ -rm -f $4
+_am_opt_rule_eof_
+fi
+],
+[am__optional_$2="$am__optional_$2"
+])])dnl
+])
+
+
+# _AM_OPTIONAL_TAR(TOOL, VAR-TAG, EXT, FLAGS)
+# -------------------------------------------
+# Single-tool tar pipe; TOOL is last, so its failure is what's caught.
+AC_DEFUN([_AM_OPTIONAL_TAR],
+[_AM_OPTIONAL_RULE([$1], [$2],
+[am--optional-dist-$1: distdir
+ @if test -n "$(am__optional_$2)"; then \
+ { tardir=$(distdir) \
+ && $(am__tar) | "$(am__optional_$2)" $4 > $(distdir).tar.$3; } \
+ || { rm -f $(distdir).tar.$3; \
+ echo "am-optional: dist-$1 failed; archive not built" >&2; }; \
+ else \
+ echo "am-optional: $1 unavailable, skipping $(distdir).tar.$3" >&2; \
+ fi; \
+ :], [$(distdir).tar.$3])dnl
+])
+
+
+# _AM_OPTIONAL_ZIP
+# ----------------
+AC_DEFUN([_AM_OPTIONAL_ZIP],
+[_AM_OPTIONAL_RULE([zip], [zip],
+[am--optional-dist-zip: distdir
+ @if test -n "$(am__optional_zip)"; then \
+ rm -f $(distdir).zip; \
+ { "$(am__optional_zip)" -rq $(distdir).zip $(distdir); } \
+ || { rm -f $(distdir).zip; \
+ echo "am-optional: dist-zip failed; archive not built" >&2; }; \
+ else \
+ echo "am-optional: zip unavailable, skipping $(distdir).zip" >&2; \
+ fi; \
+ :], [$(distdir).zip])dnl
+])
+
+
+# _AM_OPTIONAL_SHAR
+# -----------------
+# Only `shar' is optional (gzip is a hard automake prereq). shar
+# writes an intermediate file instead of piping into gzip: piped, gzip
+# would succeed on empty input and leave a bogus .shar.gz when shar
+# failed; the `&&' chain catches shar's exit instead.
+AC_DEFUN([_AM_OPTIONAL_SHAR],
+[_AM_OPTIONAL_RULE([shar], [shar],
+[am--optional-dist-shar: distdir
+ @if test -n "$(am__optional_shar)"; then \
+ rm -f $(distdir).shar $(distdir).shar.gz; \
+ { "$(am__optional_shar)" $(distdir) > $(distdir).shar \
+ && eval GZIP= gzip $(GZIP_ENV) -f $(distdir).shar; } \
+ || { rm -f $(distdir).shar $(distdir).shar.gz; \
+ echo "am-optional: dist-shar failed; archive not built" >&2; }; \
+ else \
+ echo "am-optional: shar unavailable, skipping $(distdir).shar.gz" >&2; \
+ fi; \
+ :], [$(distdir).shar $(distdir).shar.gz])dnl
+])
projects / thirdparty / automake.git / commitdiff
