Specifiy magic files, not a directory

[Shushe] / GNUmakefile

diff --git a/GNUmakefile b/GNUmakefile
index 1fe78ecd056bbda38c1036f59ca96bee05524c6f..1e809b241c73de867d3aaa268a22f5f0ebe641cd 100644 (file)
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -22,6 +22,7 @@ override define makefileinfo
 ║│ • file                                                     │║
 ║│ • find                                                     │║
 ║│ • git (optional)                                           │║
+║│ • ln                                                       │║
 ║│ • mkdir (requires support for `-p´)                        │║
 ║│ • mv                                                       │║
 ║│ • od (requires support for `-t x1´)                        │║
@@ -93,6 +94,7 @@ ECHO := echo
 FILE := file
 FIND := find
 GIT := git
+LN := ln
 MKDIR := mkdir
 MV := mv
 OD := od
@@ -134,14 +136,6 @@ DESTDIR := public
 # By default, this is inferred from the variable `MAKEFILE_LIST´.
 THISDIR := $(patsubst %/,%,$(dir $(lastword $(MAKEFILE_LIST))))
 
-# The location of the magic files to use when determining media types.
-#
-# One is provided as part of this repository, but you can override it if you need different media type detection.
-#
-# Your computer probably has a more comprehensive one installed at `/usr/share/file/magic´, but it is not recommended that you use this directly.
-# Instead, link or copy just the files you expect to need for your project.
-MAGICDIR := $(patsubst ./%,%,$(THISDIR)/magic)
-
 # Configuration of `find´.
 #
 # By default, `find´ will ignore files which begin with a period and those which are likely to cause problems for `make´.
@@ -150,6 +144,14 @@ EXTRAFINDINCLUDERULES :=
 FINDRULES := ! '(' '(' -name '[.-]*' -o -name '*[][*?:|$$%\#\\; ]*' ')' -a -prune ')'$(if $(EXTRAFINDRULES), -a $(EXTRAFINDRULES),)
 FINDINCLUDERULES := $(FINDRULES)$(if $(EXTRAFINDINCLUDERULES), -a $(EXTRAFINDINCLUDERULES),)
 
+# The list of magic files to use when determining media types.
+#
+# Some are provided as part of this repository, but you can add more if you need different media type detection.
+#
+# Your computer probably has several already installed at `/usr/share/file/magic´.
+EXTRAMAGIC :=
+MAGIC := $(sort $(patsubst ./%,%,$(wildcard $(THISDIR)/magic/*)) $(EXTRAMAGIC))
+
 # The list of parsers for plaintext file types.
 #
 # Which parsers are provided will influence which kinds of files are recognized as plaintext.
@@ -255,6 +257,15 @@ override typeoffile = $(patsubst $(foreach file,$1,$(file)|%),%,$(filter $(forea
 # (callable) Get the identifier for the given parser or transform.
 override id = $(or $(shell $(XMLLINT) --xpath '/*/*[local-name()="id" and namespace-uri()="urn:fdc:ladys.computer:20231231:Shu1She4"]/text()[1]' $1 2> /dev/null),about:shushe?$(or $2,unknown)=$(call pathenc,$(basename $(notdir $1))))
 
+# Pair each source magic file with its location in the build directory.
+override magicpair := $(foreach magicfile,$(MAGIC),$(magicfile)|$(BUILDDIR)/magic/$(notdir $(magicfile)))
+
+# (callable) Get the source file for the given magic files.
+override magicsource = $(foreach magicpath,$1,$(patsubst %|$(magicpath),%,$(firstword $(filter %|$(magicpath),$(magicpair)))))
+
+# (callable) Get the build file for the given magic files.
+override magicfile = $(foreach file,$1,$(patsubst $(file)|%,%,$(filter $(file)|%,$(magicpair))))
+
 # (callable) Get the local path for the given source file.
 override sourcepath = $(firstword $(foreach directory,$(SRCDIR),$(if $(filter $(directory)/%,$1),$(patsubst $(directory)/%,%,$1),)))
 
@@ -418,14 +429,21 @@ endif
 
 # ─ ¶ Build Targets ───────────────────────────────────────────────────
 
+# Create symbolic links from the build directory’s store of magic files
+# to their corresponding sources.
+$(call magicfile,$(MAGIC)): $(BUILDDIR)/magic/%: $$(call magicsource,$$@)
+       $(silent)$(call ensuredirectory,$(dir $@))
+       $(silent)$(LN) -sf $(call quote,$(realpath $<)) $(call quote,$@)
+
 # Generate the compiled magic file from its sources.
 #
 # It must be updated if any of the files in the magic directory change.
 # It ⁜also⁜ should be updated if any of the files in the magic directory are deleted, but this isn’t tracked presently.
-$(BUILDDIR)/magic.mgc: $(wildcard $(MAGICDIR)/*)
+$(BUILDDIR)/magic.mgc: $(call magicfile,$(MAGIC))
+       $(foreach outdated,$(filter-out $^,$(wildcard $(BUILDDIR)/magic/*)),$(silent)$(RM) $(call quote,$(outdated))$(newline))
        @$(ECHO) "Compiling new magic…"
        $(silent)$(call ensuredirectory,$(dir $@))
-       $(silent)cd $(call quote,$(BUILDDIR)) && $(FILE) -C -m $(call quote,$(realpath $(MAGICDIR)))
+       $(silent)cd $(call quote,$(BUILDDIR)) && $(FILE) -C -m $(call quote,$(realpath $(BUILDDIR)/magic))
 
 # Generate the main parser.
 $(BUILDDIR)/parser.catalog: $(PARSERS)