Replace thumbnail Makefile with configure script

The thumbnail subproject has dependencies against dynstr and
ImageMagick6, which might or might not be available on the system, or
might have been installed to non-standard paths.

Therefore, it is more robust to rely on a configure script that checks
whether the packages are available and how to deal with CFLAGS/LDFLAGS.

5 files changed, 160 insertions, 40 deletions

diff --git a/.gitignore b/.gitignore
index 759af02..c72486a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@ build/
 /slcl
 /usergen
 thumbnail/thumbnail
+/thumbnail/Makefile
 *.a
 *.o
 *.d
diff --git a/configure b/configure
index 4f42953..35a0743 100755
--- a/configure
+++ b/configure
@@ -177,7 +177,7 @@ EOF
 if [ $build_thumbnail -ne 0 ]
 then
 cat <<"EOF" >> $F
-	+cd thumbnail && $(MAKE) PREFIX=$(PREFIX) install
+	+test -f $(THUMBNAIL_MK) && cd thumbnail && $(MAKE) install || :
 EOF
 fi
 
@@ -218,9 +218,13 @@ if [ $build_thumbnail -ne 0 ]
 then
 cat <<"EOF" >> $F
 THUMBNAIL = thumbnail/thumbnail
+THUMBNAIL_MK = thumbnail/Makefile
 thumbnail $(PROJECT): $(THUMBNAIL)
-$(THUMBNAIL): FORCE
+$(THUMBNAIL_MK):
+	cd thumbnail && CFLAGS="$(CFLAGS)" ./configure --prefix=$(PREFIX)
+$(THUMBNAIL): $(THUMBNAIL_MK) FORCE
 	+cd thumbnail && $(MAKE) CC=$(CC)
+all: $(THUMBNAIL)
 EOF
 fi
 
@@ -250,6 +254,13 @@ cat <<"EOF" >> $F
 EOF
 fi
 
+if [ $build_thumbnail -ne 0 ]
+then
+cat <<"EOF" >> $F
+	+test -f $(THUMBNAIL_MK) && cd thumbnail && $(MAKE) clean || :
+EOF
+fi
+
 cat <<"EOF" >> $F
 distclean: clean
 	rm -f slcl usergen
@@ -275,7 +286,7 @@ fi
 if [ $build_thumbnail -ne 0 ]
 then
 cat <<"EOF" >> $F
-	+cd thumbnail && $(MAKE) distclean
+	+test -f $(THUMBNAIL_MK) && cd thumbnail && $(MAKE) distclean || :
 EOF
 fi
 
diff --git a/thumbnail/Makefile b/thumbnail/Makefile
deleted file mode 100644
index 4ed1944..0000000
--- a/thumbnail/Makefile
+++ /dev/null
@@ -1,36 +0,0 @@
-.POSIX:
-
-PROJECT = thumbnail
-PREFIX = /usr/local
-O = -Og
-CDEFS = -D_FILE_OFFSET_BITS=64 # Required for large file support on 32-bit.
-CFLAGS = $(O) $(CDEFS) -g -Wall -I../libweb/dynstr/include -I. \
-	$$(pkg-config --cflags ImageMagick) -MD -MF $(@:.o=.d)
-LDFLAGS = $(LIBS)
-DEPS = $(OBJECTS:.o=.d)
-DYNSTR = ../libweb/dynstr/libdynstr.a
-DYNSTR_LIBS = -L../libweb/dynstr -ldynstr
-LIBS = $$(pkg-config --libs ImageMagick) $(DYNSTR_LIBS)
-OBJECTS = \
-	crealpath.o \
-	main.o \
-	cftw.o
-
-all: $(PROJECT)
-
-install: all
-	cp thumbnail $(PREFIX)/bin/
-
-clean:
-	rm -f $(OBJECTS) $(DEPS)
-
-distclean: clean
-	rm -f $(PROJECT)
-
-$(PROJECT): $(OBJECTS) $(DYNSTR)
-	$(CC) $(OBJECTS) $(LDFLAGS) $(LIBS) -o $@
-
-$(DYNSTR):
-	+cd ../dynstr && $(MAKE)
-
--include $(DEPS)
diff --git a/thumbnail/configure b/thumbnail/configure
new file mode 100755
index 0000000..3ca488b
--- /dev/null
+++ b/thumbnail/configure
@@ -0,0 +1,144 @@
+#! /bin/sh
+
+set -e
+
+default_prefix=/usr/local
+prefix=$default_prefix
+default_CC='c99'
+# FILE_OFFSET_BITS=64 is required for large file support on 32-bit platforms.
+default_CFLAGS='-O1 -D_FILE_OFFSET_BITS=64 -MD'
+
+CC=${CC:-$default_CC}
+
+help()
+{
+	cat <<-EOF
+$0 [OPTION ...]
+
+--prefix      Set installation directory [$default_prefix]
+
+Some influential environment variables:
+  CC                  C compiler [$default_CC]
+  CFLAGS              C compiler flags [$default_CFLAGS]
+  LDFLAGS             Link-time flags [$default_LDFLAGS]
+EOF
+}
+
+while true; do
+	split_arg=0
+
+	if printf "%s" "$1" | grep -e '=' > /dev/null
+	then
+		key="$(printf "%s" "$1" | cut -d '=' -f1)"
+		value="$(printf "%s" "$1" | cut -d '=' -f2)"
+		split_arg=1
+	else
+		key="$1"
+		value="$2"
+	fi
+
+	case "$key" in
+		--prefix ) prefix="$value"; shift; test $split_arg -eq 0 && shift ;;
+		-h | --help ) help; exit 0 ;;
+		* ) test "$1" != "" && help && exit 1 || break ;;
+	esac
+done
+
+if pkg-config ImageMagick-im6
+then
+	CFLAGS="$(pkg-config --cflags ImageMagick-im6) $CFLAGS"
+	LDFLAGS="$(pkg-config --libs ImageMagick-im6) $LDFLAGS"
+else
+	echo "Error: ImageMagick-im6 not found." >&2
+	exit 1
+fi
+
+if pkg-config dynstr
+then
+	in_tree_dynstr=0
+	CFLAGS="$(pkg-config --cflags dynstr) $CFLAGS"
+	LDFLAGS="$(pkg-config --libs dynstr) $LDFLAGS"
+else
+	echo "Info: dynstr not found. Using in-tree copy" >&2
+	in_tree_dynstr=1
+	CFLAGS="-I../libweb/dynstr/include $CFLAGS"
+	LDFLAGS="-L../libweb/dynstr -ldynstr $LDFLAGS"
+fi
+
+CFLAGS="$default_CFLAGS $CFLAGS"
+LDFLAGS="$default_LDFLAGS $LDFLAGS"
+
+cleanup()
+{
+	rm -f $F
+}
+
+F=/tmp/Makefile.thumbnail
+trap cleanup EXIT
+
+cat <<EOF > $F
+.POSIX:
+
+CC = $CC
+PREFIX = $prefix
+DST = $prefix/bin
+CFLAGS = $CFLAGS
+LDFLAGS = $LDFLAGS
+EOF
+
+cat <<"EOF" >> $F
+.POSIX:
+
+PROJECT = thumbnail
+DEPS = $(OBJECTS:.o=.d)
+OBJECTS = \
+	crealpath.o \
+	main.o \
+	cftw.o
+
+all: $(PROJECT)
+
+FORCE:
+
+install: all
+	install $(PROJECT) $(PREFIX)/bin/
+
+$(PROJECT): $(OBJECTS) $(DYNSTR)
+	$(CC) $(OBJECTS) $(LDFLAGS) -o $@
+EOF
+
+if [ $in_tree_dynstr -ne 0 ]
+then
+cat <<"EOF" >> $F
+DYNSTR = ../libweb/dynstr/libdynstr.a
+$(PROJECT): $(DYNSTR)
+$(DYNSTR): FORCE
+	+cd ../libweb/dynstr && $(MAKE) CC=$(CC)
+EOF
+fi
+
+cat <<"EOF" >> $F
+clean:
+	rm -f $(OBJECTS) $(DEPS)
+EOF
+
+if [ $in_tree_dynstr -ne 0 ]
+then
+cat <<"EOF" >> $F
+	+cd ../libweb/dynstr && $(MAKE) clean
+EOF
+fi
+
+cat <<"EOF" >> $F
+distclean: clean
+	rm -f $(PROJECT)
+	rm Makefile
+EOF
+
+# dynstr has no distclean target as of the time of this writing.
+
+cat <<"EOF" >> $F
+-include $(DEPS)
+EOF
+
+mv $F Makefile
diff --git a/thumbnail/main.c b/thumbnail/main.c
index 7163043..c2bf27a 100644
--- a/thumbnail/main.c
+++ b/thumbnail/main.c
@@ -1,7 +1,7 @@
 #define _POSIX_C_SOURCE 200809L
 
 #include "crealpath.h"
-#include <cftw.h>
+#include "cftw.h"
 #include <dynstr.h>
 #include <magick/api.h>
 #include <fcntl.h>