qemu-img: Convert invocation documentation to rST

The qemu-img documentation is currently in qemu-nbd.texi in Texinfo
format, which we present to the user as:
 * a qemu-img manpage
 * a section of the main qemu-doc HTML documentation

Convert the documentation to rST format, and present it to the user as:
 * a qemu-img manpage
 * part of the interop/ Sphinx manual

The qemu-img rST document uses the new hxtool extension
to handle pulling rST fragments out of qemu-img-cmds.hx.

The documentation of the various options and commands is rather
muddled, with some options being described inside the relevant
command description and some in a more general section near the start
of the manual.  All the command synopses are replicated in the .hx
file and then again in the manual.  A lot of text is also duplicated
in the qemu-img.c code for the help text.  I have not attempted to
deal with any of this, but have simply transposed the existing
structure into rST.

As usual, there are some minor formatting changes but no
textual changes, except that as with one or two other conversions
I have dropped the 'see also' section since it's not very
informative and looks odd in the HTML.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200124162606.8787-6-peter.maydell@linaro.org

MAINTAINERS

@@ -1834,6 +1834,7 @@ F: block/
 F: hw/block/
 F: include/block/
 F: qemu-img*
+F: docs/interop/qemu-img.rst
 F: qemu-io*
 F: tests/qemu-iotests/
 F: util/qemu-progress.c

Makefile

@@ -344,7 +344,8 @@ MANUAL_BUILDDIR := docs
 endif
 
 ifdef BUILD_DOCS
-DOCS=qemu-doc.html qemu-doc.txt qemu.1 qemu-img.1
+DOCS=qemu-doc.html qemu-doc.txt qemu.1
+DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-img.1
 DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-nbd.8
 DOCS+=$(MANUAL_BUILDDIR)/interop/qemu-ga.8
 DOCS+=$(MANUAL_BUILDDIR)/system/qemu-block-drivers.7
@@ -744,7 +745,7 @@ rm -f $(MANUAL_BUILDDIR)/$1/objects.inv $(MANUAL_BUILDDIR)/$1/searchindex.js $(M
 endef
 
 distclean: clean
-	rm -f config-host.mak config-host.h* config-host.ld $(DOCS) qemu-options.texi qemu-img-cmds.texi qemu-monitor.texi qemu-monitor-info.texi
+	rm -f config-host.mak config-host.h* config-host.ld $(DOCS) qemu-options.texi qemu-monitor.texi qemu-monitor-info.texi
 	rm -f tests/tcg/config-*.mak
 	rm -f config-all-devices.mak config-all-disas.mak config.status
 	rm -f $(SUBDIR_DEVICES_MAK)
@@ -842,7 +843,7 @@ ifdef CONFIG_POSIX
 	$(INSTALL_DATA) $(MANUAL_BUILDDIR)/system/qemu-block-drivers.7 "$(DESTDIR)$(mandir)/man7"
 	$(INSTALL_DATA) docs/qemu-cpu-models.7 "$(DESTDIR)$(mandir)/man7"
 ifeq ($(CONFIG_TOOLS),y)
-	$(INSTALL_DATA) qemu-img.1 "$(DESTDIR)$(mandir)/man1"
+	$(INSTALL_DATA) $(MANUAL_BUILDDIR)/interop/qemu-img.1 "$(DESTDIR)$(mandir)/man1"
 	$(INSTALL_DIR) "$(DESTDIR)$(mandir)/man8"
 	$(INSTALL_DATA) $(MANUAL_BUILDDIR)/interop/qemu-nbd.8 "$(DESTDIR)$(mandir)/man8"
 endif
@@ -1040,7 +1041,7 @@ endef
 $(MANUAL_BUILDDIR)/devel/index.html: $(call manual-deps,devel)
 	$(call build-manual,devel,html)
 
-$(MANUAL_BUILDDIR)/interop/index.html: $(call manual-deps,interop)
+$(MANUAL_BUILDDIR)/interop/index.html: $(call manual-deps,interop) $(SRC_PATH)/qemu-img-cmds.hx
 	$(call build-manual,interop,html)
 
 $(MANUAL_BUILDDIR)/specs/index.html: $(call manual-deps,specs)
@@ -1049,7 +1050,7 @@ $(MANUAL_BUILDDIR)/specs/index.html: $(call manual-deps,specs)
 $(MANUAL_BUILDDIR)/system/index.html: $(call manual-deps,system)
 	$(call build-manual,system,html)
 
-$(call define-manpage-rule,interop,qemu-ga.8 qemu-nbd.8)
+$(call define-manpage-rule,interop,qemu-ga.8 qemu-img.1 qemu-nbd.8,$(SRC_PATH/qemu-img-cmds.hx))
 
 $(call define-manpage-rule,system,qemu-block-drivers.7)
 
@@ -1067,9 +1068,6 @@ qemu-monitor.texi: $(SRC_PATH)/hmp-commands.hx $(SRC_PATH)/scripts/hxtool
 qemu-monitor-info.texi: $(SRC_PATH)/hmp-commands-info.hx $(SRC_PATH)/scripts/hxtool
 	$(call quiet-command,sh $(SRC_PATH)/scripts/hxtool -t < $< > $@,"GEN","$@")
 
-qemu-img-cmds.texi: $(SRC_PATH)/qemu-img-cmds.hx $(SRC_PATH)/scripts/hxtool
-	$(call quiet-command,sh $(SRC_PATH)/scripts/hxtool -t < $< > $@,"GEN","$@")
-
 docs/interop/qemu-qmp-qapi.texi: qapi/qapi-doc.texi
 	@cp -p $< $@
 
@@ -1078,7 +1076,6 @@ docs/interop/qemu-ga-qapi.texi: qga/qapi-generated/qga-qapi-doc.texi
 
 qemu.1: qemu-doc.texi qemu-options.texi qemu-monitor.texi qemu-monitor-info.texi
 qemu.1: qemu-option-trace.texi
-qemu-img.1: qemu-img.texi qemu-option-trace.texi qemu-img-cmds.texi
 fsdev/virtfs-proxy-helper.1: fsdev/virtfs-proxy-helper.texi
 docs/qemu-cpu-models.7: docs/qemu-cpu-models.texi
 scripts/qemu-trace-stap.1: scripts/qemu-trace-stap.texi
@@ -1089,9 +1086,9 @@ pdf: qemu-doc.pdf docs/interop/qemu-qmp-ref.pdf docs/interop/qemu-ga-ref.pdf
 txt: qemu-doc.txt docs/interop/qemu-qmp-ref.txt docs/interop/qemu-ga-ref.txt
 
 qemu-doc.html qemu-doc.info qemu-doc.pdf qemu-doc.txt: \
-	qemu-img.texi qemu-options.texi \
+	qemu-options.texi \
 	qemu-tech.texi qemu-option-trace.texi \
-	qemu-deprecated.texi qemu-monitor.texi qemu-img-cmds.texi \
+	qemu-deprecated.texi qemu-monitor.texi \
 	qemu-monitor-info.texi \
 	docs/qemu-cpu-models.texi docs/security.texi
 

docs/interop/conf.py

@@ -19,6 +19,8 @@ html_theme_options['description'] = u'System Emulation Management and Interopera
 man_pages = [
     ('qemu-ga', 'qemu-ga', u'QEMU Guest Agent',
      ['Michael Roth <mdroth@linux.vnet.ibm.com>'], 8),
+    ('qemu-img', 'qemu-img', u'QEMU disk image utility',
+     ['Fabrice Bellard'], 1),
     ('qemu-nbd', 'qemu-nbd', u'QEMU Disk Network Block Device Server',
      ['Anthony Liguori <anthony@codemonkey.ws>'], 8)
 ]

docs/interop/index.rst

@@ -18,6 +18,7 @@ Contents:
    live-block-operations
    pr-helper
    qemu-ga
+   qemu-img
    qemu-nbd
    vhost-user
    vhost-user-gpu

qemu-doc.texi

@@ -632,7 +632,6 @@ encrypted disk images.
 * disk_images_quickstart::    Quick start for disk image creation
 * disk_images_snapshot_mode:: Snapshot mode
 * vm_snapshots::              VM snapshots
-* qemu_img_invocation::       qemu-img Invocation
 @end menu
 
 @node disk_images_quickstart
@@ -646,7 +645,9 @@ where @var{myimage.img} is the disk image filename and @var{mysize} is its
 size in kilobytes. You can add an @code{M} suffix to give the size in
 megabytes and a @code{G} suffix for gigabytes.
 
-See @ref{qemu_img_invocation} for more information.
+@c When this document is converted to rst we should make this into
+@c a proper linked reference to the qemu-img documentation again:
+See the qemu-img invocation documentation for more information.
 
 @node disk_images_snapshot_mode
 @subsection Snapshot mode
@@ -708,11 +709,6 @@ A few device drivers still have incomplete snapshot support so their
 state is not saved or restored properly (in particular USB).
 @end itemize
 
-@node qemu_img_invocation
-@subsection @code{qemu-img} Invocation
-
-@include qemu-img.texi
-
 @node pcsys_network
 @section Network emulation