make it possible to keep usage texts in .c files

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

Makefile.custom

@@ -118,7 +118,7 @@ disp_doc       = $($(quiet)cmd_doc)
 # sed adds newlines after "Options:" etc,
 # this is needed in order to get good BusyBox.{1,txt,html}
 docs/busybox.pod: $(srctree)/docs/busybox_header.pod \
-		$(srctree)/include/usage.h \
+		include/usage.h \
 		$(srctree)/docs/busybox_footer.pod \
 		applets/usage_pod
 	$(disp_doc)

archival/bbunzip.c

@@ -304,6 +304,17 @@ int gunzip_main(int argc UNUSED_PARAM, char **argv)
  *
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
+//usage:#define bunzip2_trivial_usage
+//usage:       "[OPTIONS] [FILE]..."
+//usage:#define bunzip2_full_usage "\n\n"
+//usage:       "Decompress FILEs (or stdin)\n"
+//usage:     "\nOptions:"
+//usage:     "\n	-c	Write to stdout"
+//usage:     "\n	-f	Force"
+//usage:#define bzcat_trivial_usage
+//usage:       "FILE"
+//usage:#define bzcat_full_usage "\n\n"
+//usage:       "Decompress to stdout"
 //applet:IF_BUNZIP2(APPLET(bunzip2, _BB_DIR_USR_BIN, _BB_SUID_DROP))
 //applet:IF_BUNZIP2(APPLET_ODDNAME(bzcat, bunzip2, _BB_DIR_USR_BIN, _BB_SUID_DROP, bzcat))
 #if ENABLE_BUNZIP2

include/usage.src.h

@@ -15,6 +15,8 @@
 
 #define NOUSAGE_STR "\b"
 
+INSERT
+
 #define acpid_trivial_usage \
        "[-d] [-c CONFDIR] [-l LOGFILE] [-e PROC_EVENT_FILE] [EVDEV_EVENT_FILE]..."
 #define acpid_full_usage "\n\n" \
@@ -234,19 +236,6 @@
      "\n	-v	Verbose" \
      "\n	-F	Don't store or verify checksum" \
 
-#define bunzip2_trivial_usage \
-       "[OPTIONS] [FILE]..."
-#define bunzip2_full_usage "\n\n" \
-       "Decompress FILEs (or stdin)\n" \
-     "\nOptions:" \
-     "\n	-c	Write to stdout" \
-     "\n	-f	Force" \
-
-#define bzcat_trivial_usage \
-       "FILE"
-#define bzcat_full_usage "\n\n" \
-       "Decompress to stdout"
-
 #define unlzma_trivial_usage \
        "[OPTIONS] [FILE]..."
 #define unlzma_full_usage "\n\n" \

scripts/Makefile.IMA

@@ -200,7 +200,7 @@ applets/usage: include/autoconf.h
 applets/applet_tables: include/autoconf.h
 	$(HOSTCC) -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -I$(srctree)/include -o applets/applet_tables applets/applet_tables.c
 
-include/usage_compressed.h: $(srctree)/include/usage.h applets/usage
+include/usage_compressed.h: include/usage.h applets/usage
 	$(srctree)/applets/usage_compressed include/usage_compressed.h applets
 
 include/applet_tables.h: include/applets.h

scripts/gen_build_files.sh

@@ -10,7 +10,7 @@ srctree="$1"
 # (Re)generate include/applets.h
 src="$srctree/include/applets.src.h"
 dst="include/applets.h"
-s=`sed -n 's@^//applet:@@p' -- */*.c */*/*.c`
+s=`sed -n 's@^//applet:@@p' -- "$srctree"/*/*.c "$srctree"/*/*/*.c`
 echo "/* DO NOT EDIT. This file is generated from applets.src.h */" >"$dst.$$.tmp"
 # Why "IFS='' read -r REPLY"??
 # This atrocity is needed to read lines without mangling.
@@ -27,6 +27,30 @@ else
 	mv -- "$dst.$$.tmp" "$dst"
 fi
 
+# (Re)generate include/usage.h
+src="$srctree/include/usage.src.h"
+dst="include/usage.h"
+# We add line continuation backslash after each line,
+# and insert empty line before each line which doesn't start
+# with space or tab
+# (note: we need to use \\\\ because of ``)
+s=`sed -n -e 's@^//usage:\([ \t].*\)$@\1 \\\\@p' -e 's@^//usage:\([^ \t].*\)$@\n\1 \\\\@p' -- "$srctree"/*/*.c "$srctree"/*/*/*.c`
+echo "/* DO NOT EDIT. This file is generated from usage.src.h */" >"$dst.$$.tmp"
+# Why "IFS='' read -r REPLY"??
+# This atrocity is needed to read lines without mangling.
+# IFS='' prevents whitespace trimming,
+# -r suppresses backslash handling.
+while IFS='' read -r REPLY; do
+	test x"$REPLY" = x"INSERT" && REPLY="$s"
+	printf "%s\n" "$REPLY"
+done <"$src" >>"$dst.$$.tmp"
+if test -f "$dst" && cmp -s "$dst.$$.tmp" "$dst"; then
+	rm -- "$dst.$$.tmp"
+else
+	echo "  GEN     $dst"
+	mv -- "$dst.$$.tmp" "$dst"
+fi
+
 # (Re)generate */Kbuild and */Config.in
 find -type d | while read -r d; do
 	d="${d#./}"