Exctracting source code from EXAMPLES

["Alejandro Colomar (man-pages)" <alx.manpages@xxxxxxxxx>]

Gidday!

I have ready some code to extract source code from EXAMPLES in man-pages.
For that, I set up some convention:

Enclose the code (including the enclosing .EX/.EE in a pair of comments
with a very precise formatting:

[[
...
.\" SRC BEGIN (program_name.c)
.EX
#include <stdio.h>

int main(void)
{
	printf("Hello, world!");
}
.EE
.\" SRC END
...
]]

There can be multiple programs in a single page, with the only
restriction that each of them has to have a different program_name
(there can be collisions within different manual pages, but not within
the same manual page)

The Makefile will create a directory for each manal page, where the
different programs will be created with the name specified in the
comment (that's why it has to be different from others in the same page
only).

Please, check that you like what you see, and comment if not (or if yes
too :).

I tested it with membarrier.2, and it produced a correct .c file.
The next step will be to add targets to lint and compile the produced
files, to check their correctness.

I hope this will make our lives much easier maintaining manual pages :-)


Cheers,

Alex



diff --git a/Makefile b/Makefile
index 03ebde18c..05a1b5950 100644
--- a/Makefile
+++ b/Makefile
@@ -30,19 +30,20 @@ MAKEFLAGS += --no-print-directory
 MAKEFLAGS += --warn-undefined-variables


-srcdir := .
+srcdir   := .
 builddir := tmp
-LINTDIR := $(builddir)/lint
-HTMLDIR := $(builddir)/html
+LINTDIR  := $(builddir)/lint
+HTMLDIR  := $(builddir)/html
+SRCDIR   := $(builddir)/src

 DESTDIR :=
-prefix := /usr/local
-SYSCONFDIR := $(srcdir)/etc
-TMACDIR := $(SYSCONFDIR)/groff/tmac
+prefix  := /usr/local
+SYSCONFDIR  := $(srcdir)/etc
+TMACDIR     := $(SYSCONFDIR)/groff/tmac
 datarootdir := $(prefix)/share
-docdir := $(datarootdir)/doc
-MANDIR := $(srcdir)
-mandir := $(datarootdir)/man
+docdir  := $(datarootdir)/doc
+MANDIR  := $(srcdir)
+mandir  := $(datarootdir)/man
 MAN0DIR := $(MANDIR)/man0
 MAN1DIR := $(MANDIR)/man1
 MAN2DIR := $(MANDIR)/man2
@@ -61,7 +62,7 @@ man5dir := $(mandir)/man5
 man6dir := $(mandir)/man6
 man7dir := $(mandir)/man7
 man8dir := $(mandir)/man8
-manext := \.[0-9]
+manext  := \.[0-9]
 man0ext := .0
 man1ext := .1
 man2ext := .2
@@ -71,9 +72,9 @@ man5ext := .5
 man6ext := .6
 man7ext := .7
 man8ext := .8
-htmldir := $(docdir)
+htmldir  := $(docdir)
 htmldir_ := $(htmldir)/man
-htmlext := .html
+htmlext  := .html

 TMACFILES            := $(sort $(shell find $(TMACDIR) -not -type d))
 TMACNAMES            := $(basename $(notdir $(TMACFILES)))
@@ -99,9 +100,11 @@ MAN2HTMLFLAGS         := $(DEFAULT_MAN2HTMLFLAGS)
$(EXTRA_MAN2HTMLFLAGS)
 INSTALL      := install
 INSTALL_DATA := $(INSTALL) -m 644
 INSTALL_DIR  := $(INSTALL) -m 755 -d
+MKDIR        := mkdir -p
 RM           := rm
 RMDIR        := rmdir --ignore-fail-on-non-empty
 GROFF        := groff
+MAN          := man
 MANDOC       := mandoc
 MAN2HTML     := man2html

@@ -161,12 +164,14 @@ _man5pages := $(filter %$(man5ext),$(_manpages))
 _man6pages := $(filter %$(man6ext),$(_manpages))
 _man7pages := $(filter %$(man7ext),$(_manpages))
 _man8pages := $(filter %$(man8ext),$(_manpages))
-LINT_groff := $(patsubst
$(MANDIR)/%,$(LINTDIR)/%.lint.groff.touch,$(LINTPAGES))
-LINT_mandoc:= $(patsubst
$(MANDIR)/%,$(LINTDIR)/%.lint.mandoc.touch,$(LINTPAGES))
+LINT_groff :=$(patsubst
$(MANDIR)/%,$(LINTDIR)/%.lint.groff.touch,$(LINTPAGES))
+LINT_mandoc:=$(patsubst
$(MANDIR)/%,$(LINTDIR)/%.lint.mandoc.touch,$(LINTPAGES))
+SRCPAGEDIRS:=$(patsubst $(MANDIR)/%,$(SRCDIR)/%,$(LINTPAGES))

 MANDIRS   := $(sort $(shell find $(MANDIR)/man? -type d))
 HTMLDIRS  := $(patsubst $(MANDIR)/%,$(HTMLDIR)/%/.,$(MANDIRS))
 LINTDIRS  := $(patsubst $(MANDIR)/%,$(LINTDIR)/%/.,$(MANDIRS))
+SRCDIRS   := $(patsubst $(MANDIR)/%,$(SRCDIR)/%/.,$(MANDIRS))
 _htmldirs := $(patsubst $(HTMLDIR)/%,$(DESTDIR)$(htmldir_)/%,$(HTMLDIRS))
 _mandirs  := $(patsubst $(MANDIR)/%,$(DESTDIR)$(mandir)/%/.,$(MANDIRS))
 _man0dir  := $(filter %man0/.,$(_mandirs))
@@ -248,6 +253,37 @@ uninstall-man: $(_mandir_rmdir) $(uninstall_manX)
        @:


+########################################################################
+# src
+
+$(SRCPAGEDIRS): $(SRCDIR)/%: $(MANDIR)/% | $$(@D)/.
+       $(info MKDIR    $@ $<)
+       $(RM) -rf $@
+       $(MKDIR) $@.tmp
+       <$< \
+       sed -n 's/\.\\" SRC BEGIN (\(.*.c\))/\1/p' \
+       | while read f; do \
+               <$< \
+               sed -n \
+                       -e '/^\.TH/,/^\.SH/{/^\.SH/!p}' \
+                       -e '/^\.SH EXAMPLES/p' \
+                       -e "/^\... SRC BEGIN ($$f)$$/,/^\... SRC END$$/p" \
+               | $(MAN) -P cat -l - \
+               | sed '/^[^ ]/d' \
+               >$@.tmp/$$f; \
+       done \
+       || exit $$?
+       mv -T $@.tmp $@
+
+.PHONY: build-src src
+build-src src: $(SRCPAGEDIRS) | builddirs-src
+       @:
+
+.PHONY: builddirs-src
+builddirs-src: $(SRCDIRS)
+       @:
+
+
 ########################################################################
 # lint

diff --git a/man2/membarrier.2 b/man2/membarrier.2
index b2e3e035e..a46283dd7 100644
--- a/man2/membarrier.2
+++ b/man2/membarrier.2
@@ -319,6 +319,7 @@ following code (x86) can be transformed using
 .BR membarrier ():
 .PP
 .in +4n
+.\" SRC BEGIN (membarrier.c)
 .EX
 #include <stdlib.h>

@@ -365,6 +366,7 @@ main(int argc, char *argv[])
     exit(EXIT_SUCCESS);
 }
 .EE
+.\" SRC END
 .in
 .PP
 The code above transformed to use


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/