Add a simple Makefile-based build system.

This produces static/shared libraries as well as a pkg-config file, and
installs them to the standard Unix hierarchy. GNU Make is assumed as
features like $(wildcard ...) or $(shell uname) may not work elsewhere,
but it should otherwise build on most/all Unix platforms.

Note that we assume the following POSIX default rules/macros exist, so
we don't bother redefining them:
- pattern rules for compiling .c -> .o
- $(CC)
- $(AR)

Special note on the .pc file generation: we do most variable
replacements in one go, but delay @PREFIX@ so that we can first find
existing substring instances of the prefix value (if libdir/includedir
reside within the prefix), and update them to use a literal pkg-config
variable '${prefix}'. This is fairly compact (one single sed) while
still letting us produce pkg-config files that support runtime
redefinition à la cross-compilation.

Makefile

@@ -0,0 +1,71 @@
+VERSION := 0.6.3
+
+# install directory layout
+PREFIX ?= /usr/local
+INCLUDEDIR ?= $(PREFIX)/include
+LIBDIR ?= $(PREFIX)/lib
+PCLIBDIR ?= $(LIBDIR)/pkgconfig
+
+# collect sources
+ifneq ($(AMALGAMATED),1)
+	SRC := $(wildcard lib/src/*.c)
+	# do not double-include amalgamation
+	SRC := $(filter-out lib/src/lib.c,$(SRC))
+else
+	# use amalgamated build
+	SRC := lib/src/lib.c
+endif
+OBJ := $(SRC:.c=.o)
+
+# define default flags, and override to append mandatory flags
+CFLAGS ?= -O3
+override CFLAGS += -std=gnu99 -fPIC -Ilib/src -Ilib/include
+
+# ABI versioning
+SONAME_MAJOR := 0
+SONAME_MINOR := 0
+
+# OS-specific bits
+ifeq ($(shell uname),Darwin)
+	SOEXT = dylib
+	SOEXTVER_MAJOR = $(SONAME_MAJOR).dylib
+	SOEXTVER = $(SONAME_MAJOR).$(SONAME_MINOR).dylib
+	LINKSHARED += -dynamiclib -Wl,-install_name,$(LIBDIR)/libtree-sitter.$(SONAME_MAJOR).dylib
+else
+	SOEXT = so
+	SOEXTVER_MAJOR = so.$(SONAME_MAJOR)
+	SOEXTVER = so.$(SONAME_MAJOR).$(SONAME_MINOR)
+	LINKSHARED += -shared -Wl,-soname,libtree-sitter.so.$(SONAME_MAJOR)
+endif
+ifneq (,$(filter $(shell uname),FreeBSD NetBSD DragonFly))
+	PCLIBDIR := $(PREFIX)/libdata/pkgconfig
+endif
+
+all: libtree-sitter.a libtree-sitter.$(SOEXTVER)
+
+libtree-sitter.a: $(OBJ)
+	$(AR) rcs $@ $^
+
+libtree-sitter.$(SOEXTVER): $(OBJ)
+	$(CC) $(LDFLAGS) $(LINKSHARED) $^ $(LDLIBS) -o $@
+	ln -sf $@ libtree-sitter.$(SOEXT)
+	ln -sf $@ libtree-sitter.$(SOEXTVER_MAJOR)
+
+install: all
+	install -d '$(DESTDIR)$(LIBDIR)'
+	install -m755 libtree-sitter.a '$(DESTDIR)$(LIBDIR)'/libtree-sitter.a
+	install -m755 libtree-sitter.$(SOEXTVER) '$(DESTDIR)$(LIBDIR)'/libtree-sitter.$(SOEXTVER)
+	ln -sf libtree-sitter.$(SOEXTVER) '$(DESTDIR)$(LIBDIR)'/libtree-sitter.$(SOEXTVER_MAJOR)
+	ln -sf libtree-sitter.$(SOEXTVER) '$(DESTDIR)$(LIBDIR)'/libtree-sitter.$(SOEXT)
+	install -d '$(DESTDIR)$(INCLUDEDIR)'/tree_sitter
+	install -m644 lib/include/tree_sitter/*.h '$(DESTDIR)$(INCLUDEDIR)'/tree_sitter/
+	install -d '$(DESTDIR)$(PCLIBDIR)'
+	sed -e 's|@LIBDIR@|$(LIBDIR)|;s|@INCLUDEDIR@|$(INCLUDEDIR)|;s|@VERSION@|$(VERSION)|' \
+	    -e 's|=$(PREFIX)|=$${prefix}|' \
+	    -e 's|@PREFIX@|$(PREFIX)|' \
+	    tree-sitter.pc.in > '$(DESTDIR)$(PCLIBDIR)'/tree-sitter.pc
+
+clean:
+	rm -f lib/src/*.o libtree-sitter.a libtree-sitter.$(SOEXT) libtree-sitter.$(SOEXTVER_MAJOR) libtree-sitter.$(SOEXTVER)
+
+.PHONY: all install clean

tree-sitter.pc.in

@@ -0,0 +1,10 @@
+prefix=@PREFIX@
+libdir=@LIBDIR@
+includedir=@INCLUDEDIR@
+
+Name: tree-sitter
+Description: An incremental parsing system for programming tools
+URL: https://tree-sitter.github.io/
+Version: @VERSION@
+Libs: -L${libdir} -ltree-sitter
+Cflags: -I${includedir}