build: put the generated header under include/ for relocated builds

Previously the generated database/database.h was written to the build
top and exposed with -I${MAGICDIR}.  Out-of-tree that placed the raw
build directory on the compiler's include search path.

Introduce ${GENINC}, the single include dir for generated headers:
  * in-tree  (build top == source top): ${MAGICDIR}, so the header stays
    at $(builddir)/database/database.h and -I${GENINC} is exactly the old
    -I${MAGICDIR} -- behaviour is unchanged.
  * relocated (out-of-tree): ${MAGICDIR}/include, so the header is written
    to $(builddir)/include/database/database.h and only that clean
    include/ dir is on the search path; the raw build top never is.

* scripts/defs.mak.in: derive GENINC from BUILD_TOP vs MAGICSRC; add
  DATABASE_H = ${GENINC}/database/database.h; CPPFLAGS uses -I${GENINC}.
* Makefile.in: the makedbh rule targets ${DATABASE_H} (mkdir its dir);
  every prereq and the distclean use ${DATABASE_H}.
* database/Makefile: the fallback delegate targets ${DATABASE_H}.

Verified: relocated `make modules` builds all 33 module libraries with
the header at build/include/database/database.h and no raw build-top on
any -I line; in-tree the header stays at database/database.h and the
-I set is unchanged.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Makefile.in

@@ -44,21 +44,23 @@ defs.mak:
 config:
 	${MAGICSRC}/configure
 
-tcllibrary: database/database.h modules
+tcllibrary: ${DATABASE_H} modules
 	@echo --- making Tcl shared libraries
 	for dir in ${PROGRAMS}; do \
 		mkdir -p $$dir && ${MAKE} -C $$dir -f ${MAGICSRC}/$$dir/Makefile tcl-main || exit 1; done
 
-mains: database/database.h modules libs
+mains: ${DATABASE_H} modules libs
 	@echo --- making main programs
 	for dir in ${PROGRAMS}; do \
 		mkdir -p $$dir && ${MAKE} -C $$dir -f ${MAGICSRC}/$$dir/Makefile main || exit 1; done
 
 # makedbh is the one generated helper script; it lives in the *build* tree.
-database/database.h: ${MAGICSRC}/database/database.h.in
-	@echo --- making header file database/database.h
-	@mkdir -p database
-	${MAGICDIR}/scripts/makedbh ${MAGICSRC}/database/database.h.in database/database.h
+# ${DATABASE_H} is $(builddir)/database/database.h in-tree, or
+# $(builddir)/include/database/database.h when relocated (see defs.mak GENINC).
+${DATABASE_H}: ${MAGICSRC}/database/database.h.in
+	@echo --- making header file ${DATABASE_H}
+	@mkdir -p $(dir ${DATABASE_H})
+	${MAGICDIR}/scripts/makedbh ${MAGICSRC}/database/database.h.in ${DATABASE_H}
 
 # tiles xyz => tiles/libtiles.o xyz/libxyz.o
 MODULES_SUBDIR := $(shell for i in ${MODULES}; do echo "$${i}/lib$${i}.o"; done)
@@ -70,14 +72,14 @@ ${MODULES_SUBDIR}: FORCE
 	@d=$(dir $@); mkdir -p $$d && ${MAKE} -C $$d -f ${MAGICSRC}/$${d}Makefile module
 
 .PHONY: modules
-modules: database/database.h depend ${MODULES_SUBDIR}
+modules: ${DATABASE_H} depend ${MODULES_SUBDIR}
 
 ${LIBS_SUBDIR}: FORCE
 	@d=$(dir $@); mkdir -p $$d && ${MAKE} -C $$d -f ${MAGICSRC}/$${d}Makefile lib
 
 # Force the tiles/utils modules to exist first for libdatabase.a
 .PHONY: libs
-libs: database/database.h depend tiles/libtiles.o utils/libutils.o ${LIBS_SUBDIR}
+libs: ${DATABASE_H} depend tiles/libtiles.o utils/libutils.o ${LIBS_SUBDIR}
 
 #
 # extcheck - utility tool
@@ -94,7 +96,7 @@ SUBDIRS_FILTERED := $(shell echo ${MODULES} ${PROGRAMS} ${SUBDIRS} | tr ' ' '\n'
 
 SUBDIRS_DEPEND = $(addsuffix /Depend, ${SUBDIRS_FILTERED})
 
-${SUBDIRS_DEPEND}: database/database.h
+${SUBDIRS_DEPEND}: ${DATABASE_H}
 	@echo --- making dependencies
 	@d=$(dir $@); mkdir -p $$d && ${MAKE} -C $$d -f ${MAGICSRC}/$${d}Makefile depend
 
@@ -162,7 +164,7 @@ distclean:
 	${RM} defs.mak old.defs.mak
 	${RM} scripts/makedbh scripts/default.conf
 	${RM} config.log config.status
-	${RM} database/database.h
+	${RM} ${DATABASE_H}
 	${RM} scripts/magic.spec magic-${VERSION} magic-${VERSION}.tgz
 	${RM} *.log
 

database/Makefile

@@ -25,8 +25,9 @@ LIB_OBJS += ${MAGICDIR}/tiles/libtiles.o ${MAGICDIR}/utils/libutils.o
 # start of top level build) and removed last (near the end of a top level clean).
 #CLEANS += database.h
 
-# This is delegated back to the top level Makefile
-database.h: ${MAGICDIR}/database/database.h.in
-	${MAKE} -C ${MAGICDIR} database/database.h
+# This is delegated back to the top level Makefile, which owns ${DATABASE_H}
+# (its location varies with in-tree vs relocated builds -- see defs.mak GENINC).
+database.h: ${MAGICSRC}/database/database.h.in
+	${MAKE} -C ${MAGICDIR} $(patsubst ${MAGICDIR}/%,%,${DATABASE_H})
 
 include ${MAGICDIR}/rules.mak

scripts/defs.mak.in

@@ -32,6 +32,20 @@ srcdir                 := $(MAGICSRC)$(MODULE_SUBPATH)
 ifneq ($(MODULE_SUBPATH),)
 VPATH                  := $(srcdir)
 endif
+
+# Generated headers (currently just database/database.h) are exposed through a
+# single include directory, ${GENINC}:
+#   * in-tree  (build top == source top): the top itself, so the header stays at
+#     $(builddir)/database/database.h and -I${GENINC} == the old -I${MAGICDIR}.
+#   * relocated (out-of-tree): a clean $(builddir)/include, so #include
+#     <database/database.h> resolves under include/ and the raw build top is
+#     never on the compiler search path.
+ifeq ($(BUILD_TOP),$(MAGICSRC))
+GENINC                 := ${MAGICDIR}
+else
+GENINC                 := ${MAGICDIR}/include
+endif
+DATABASE_H             := ${GENINC}/database/database.h
 # --------------------------------------------------------------------------
 
 prefix = @prefix@
@@ -141,10 +155,10 @@ CXX		       = @CXX@
 ###   Status: NOT-STABILITY-AFFECTING (if your binary links you are good to continue)
 #FEATURE_FLAGS += -DSUPPORT_REMOVE_MALLOC_LEGACY
 
-# -I${MAGICDIR}: build top, for the generated database/database.h
+# -I${GENINC}:  generated headers (build top in-tree, build/include relocated)
 # -I${MAGICSRC}: source top, for "<module>/<header>.h" includes
 # -I${srcdir}:   this module's source dir, for same-directory headers
-CPPFLAGS               = -I${MAGICDIR} -I${MAGICSRC} -I${srcdir} @CPPFLAGS@
+CPPFLAGS               = -I${GENINC} -I${MAGICSRC} -I${srcdir} @CPPFLAGS@
 CXXFLAGS               = @CXXFLAGS@
 # Bundled GNU readline: its headers use <readline/*.h> includes, so the readline
 # source's parent directory must be on the include path.  Only for the bundled