Added the new variable CTAGS which, if set to "ctags", reverts

to creating the tags file using ctags(1).  Defaults to "gtags".
Made GTAGSFLAGS and HTAGSFLAGS overrideable, added CTAGSFLAGS.
Folded bsd.prog.mk version of `tags' into bsd.dep.mk.

PR:		bin/42852

share/mk/bsd.dep.mk

@@ -5,8 +5,16 @@
 #
 # +++ variables +++
 #
+# CTAGS		A tags file generation program [gtags]
+#
+# CTAGSFLAGS	Options for ctags(1) [not set]
+#
 # DEPENDFILE	dependencies file [.depend]
 #
+# GTAGSFLAGS	Options for gtags(1) [-o]
+#
+# HTAGSFLAGS	Options for htags(1) [not set]
+#
 # MKDEP		Options for ${MKDEPCMD} [not set]
 #
 # MKDEPCMD	Makefile dependency list program [mkdep]
@@ -24,13 +32,20 @@
 #		them in the file ${DEPENDFILE}.
 #
 #	tags:
-#		Create a (GLOBAL) gtags file for the source files.
-#		If HTML is defined, htags is also run after gtags.
+#		In "ctags" mode, create a tags file for the source files.
+#		In "gtags" mode, create a (GLOBAL) gtags file for the
+#		source files.  If HTML is defined, htags(1) is also run
+#		after gtags(1).
 
 .if !target(__<bsd.init.mk>__)
 .error bsd.dep.mk cannot be included directly.
 .endif
 
+CTAGS?=		gtags
+CTAGSFLAGS?=
+GTAGSFLAGS?=	-o
+HTAGSFLAGS?=
+
 .if ${CC} != "cc"
 MKDEPCMD?=	CC='${CC}' mkdep
 .else
@@ -38,6 +53,20 @@ MKDEPCMD?=	mkdep
 .endif
 DEPENDFILE?=	.depend
 
+# Keep `tags' here, before SRCS are mangled below for `depend'.
+.if !target(tags) && defined(SRCS) && !defined(NOTAGS)
+tags: ${SRCS}
+.if ${CTAGS:T} == "ctags"
+	@${CTAGS} ${CTAGSFLAGS} -f /dev/stdout \
+	    ${.ALLSRC:N*.h} | sed "s;${.CURDIR}/;;" > ${.TARGET}
+.elif ${CTAGS:T} == "gtags"
+	@cd ${.CURDIR} && ${CTAGS} ${GTAGSFLAGS} ${.OBJDIR}
+.if defined(HTML)
+	@cd ${.CURDIR} && htags ${HTAGSFLAGS} -d ${.OBJDIR} ${.OBJDIR}
+.endif
+.endif
+.endif
+
 .if defined(SRCS)
 CLEANFILES?=
 
@@ -128,25 +157,16 @@ afterdepend:
 .endif
 .endif
 
-.if defined(NOTAGS)
-tags:
-.endif
-
-.if !target(tags)
-tags: ${SRCS}
-	@cd ${.CURDIR} && gtags ${GTAGSFLAGS} ${.OBJDIR}
-.if defined(HTML)
-	@cd ${.CURDIR} && htags ${HTAGSFLAGS} -d ${.OBJDIR} ${.OBJDIR}
-.endif
-.endif
-
 .if !target(cleandepend)
 cleandepend:
 .if defined(SRCS)
-	rm -f ${DEPENDFILE} ${.OBJDIR}/GPATH ${.OBJDIR}/GRTAGS \
-		${.OBJDIR}/GSYMS ${.OBJDIR}/GTAGS
+.if ${CTAGS:T} == "ctags"
+	rm -f ${DEPENDFILE} tags
+.elif ${CTAGS:T} == "gtags"
+	rm -f ${DEPENDFILE} GPATH GRTAGS GSYMS GTAGS
 .if defined(HTML)
-	rm -rf ${.OBJDIR}/HTML
+	rm -rf HTML
+.endif
 .endif
 .endif
 .endif

share/mk/bsd.prog.mk

@@ -163,20 +163,6 @@ lint: ${SRCS:M*.c}
 .endif
 .endif
 
-.if defined(NOTAGS)
-tags:
-.endif
-
-.if !target(tags)
-tags: ${SRCS}
-.if defined(PROG)
-	@cd ${.CURDIR} && gtags ${GTAGSFLAGS} ${.OBJDIR}
-.if defined(HTML)
-	@cd ${.CURDIR} && htags ${HTAGSFLAGS} -d ${.OBJDIR} ${.OBJDIR}
-.endif
-.endif
-.endif
-
 .if !defined(NOMAN)
 .include <bsd.man.mk>
 .endif

share/mk/sys.mk

@@ -108,10 +108,6 @@ YFLAGS		?=	-d
 # as an i386 architecture.
 MACHINE_ARCH	?=	i386
 
-# For tags rule.
-GTAGSFLAGS=	-o
-HTAGSFLAGS=
-
 .if defined(%POSIX)
 # Posix 1003.2 mandated rules
 #