[PATCH 2/8] doc: add an asciidoc helper

[Felipe Contreras <felipe.contreras@gmail.com>]

The hacks to deal with interrupted builds is scattered throughout the
Makefile, but not everywhere (it's not done for techical/ and articles).

It originally comes from f9dae0d3e6 (Documentation/Makefile: fix
interrupted builds of user-manual.xml, 2010-04-21), however, that
description is not correct.

asciidoc does actually remove the output file in case of an exception,
but there was a bug that handled keyboard interruptions through a
different path, and thus in that particular case the file is not
removed[1].

We shouldn't overly complicate the Makefile due to bugs in asciidoc.

In order to keep the Makefile clean this commit creates an asciidoc
wrapper that does the job of tracking the intermediary output.

Once asciidoc is fixed this helper can be safely removed and there would
be minimal changes elsewhere.

It's written for bash, but could easily be modified for something more
portable.

[1] https://github.com/asciidoc-py/asciidoc-py/pull/195

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 Documentation/Makefile           | 27 +++++++++------------------
 Documentation/asciidoc-helper.sh | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 18 deletions(-)
 create mode 100755 Documentation/asciidoc-helper.sh

diff --git a/Documentation/Makefile b/Documentation/Makefile
index 3d282a2797..5c2a3df24a 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -139,8 +139,9 @@ ASCIIDOC_CONF = -f asciidoc.conf
 ASCIIDOC_COMMON = $(ASCIIDOC) $(ASCIIDOC_EXTRA) $(ASCIIDOC_CONF) \
 		-amanversion=$(GIT_VERSION) \
 		-amanmanual='Git Manual' -amansource='Git'
-TXT_TO_HTML = $(ASCIIDOC_COMMON) -b $(ASCIIDOC_HTML)
-TXT_TO_XML = $(ASCIIDOC_COMMON) -b $(ASCIIDOC_DOCBOOK)
+ASCIIDOC_BASE = '$(SHELL_PATH_SQ)' ./asciidoc-helper.sh $(ASCIIDOC_COMMON)
+TXT_TO_HTML = $(ASCIIDOC_BASE) -b $(ASCIIDOC_HTML)
+TXT_TO_XML = $(ASCIIDOC_BASE) -b $(ASCIIDOC_DOCBOOK)
 MANPAGE_XSL = manpage-normal.xsl
 XMLTO = xmlto
 XMLTO_EXTRA =
@@ -355,14 +356,10 @@ clean:
 	$(RM) GIT-ASCIIDOCFLAGS
 
 $(MAN_HTML): %.html : %.txt asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS
-	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
-	$(TXT_TO_HTML) -d manpage -o $@+ $< && \
-	mv $@+ $@
+	$(QUIET_ASCIIDOC)$(TXT_TO_HTML) -d manpage -o $@ $<
 
 $(OBSOLETE_HTML): %.html : %.txto asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS
-	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
-	$(TXT_TO_HTML) -o $@+ $< && \
-	mv $@+ $@
+	$(QUIET_ASCIIDOC)$(TXT_TO_HTML) -o $@ $<
 
 manpage-base-url.xsl: manpage-base-url.xsl.in
 	$(QUIET_GEN)sed "s|@@MAN_BASE_URL@@|$(MAN_BASE_URL)|" $< > $@
@@ -372,14 +369,10 @@ manpage-base-url.xsl: manpage-base-url.xsl.in
 	$(XMLTO) -m $(MANPAGE_XSL) $(XMLTO_EXTRA) man $<
 
 %.xml : %.txt asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS
-	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
-	$(TXT_TO_XML) -d manpage -o $@+ $< && \
-	mv $@+ $@
+	$(QUIET_ASCIIDOC)$(TXT_TO_XML) -d manpage -o $@ $<
 
 user-manual.xml: user-manual.txt user-manual.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS
-	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
-	$(TXT_TO_XML) -d book -o $@+ $< && \
-	mv $@+ $@
+	$(QUIET_ASCIIDOC)$(TXT_TO_XML) -d book -o $@ $<
 
 technical/api-index.txt: technical/api-index-skel.txt \
 	technical/api-index.sh $(patsubst %,%.txt,$(API_DOCS))
@@ -448,10 +441,8 @@ WEBDOC_DEST = /pub/software/scm/git/docs
 
 howto/%.html: ASCIIDOC_EXTRA += -a git-relative-html-prefix=../
 $(patsubst %.txt,%.html,$(HOWTO_TXT)): %.html : %.txt GIT-ASCIIDOCFLAGS
-	$(QUIET_ASCIIDOC)$(RM) $@+ $@ && \
-	sed -e '1,/^$$/d' $< | \
-	$(TXT_TO_HTML) -o $@+ - && \
-	mv $@+ $@
+	$(QUIET_ASCIIDOC)sed -e '1,/^$$/d' $< | \
+	$(TXT_TO_HTML) -o $@ -
 
 install-webdoc : html
 	'$(SHELL_PATH_SQ)' ./install-webdoc.sh $(WEBDOC_DEST)
diff --git a/Documentation/asciidoc-helper.sh b/Documentation/asciidoc-helper.sh
new file mode 100755
index 0000000000..ae16cf9288
--- /dev/null
+++ b/Documentation/asciidoc-helper.sh
@@ -0,0 +1,18 @@
+#!/bin/bash
+
+# This helper is a workaround for an interruption bug in asciidoc:
+# https://github.com/asciidoc-py/asciidoc-py/pull/195
+
+args=()
+
+while [ $# -gt 1 ]; do
+	case $1 in
+	-o) shift; out="$1" ;;
+	*) args+=("$1")
+	esac
+	shift
+done
+
+rm -f "$out+" "$out" &&
+"${args[@]}" -o "$out+" "$1" &&
+mv "$out+" "$out"
-- 
2.31.1