Issue #23: Build improvements with easier packaging in mind

.gitignore

@@ -16,4 +16,4 @@ site/**
 *.swp
 README-headless.md
 TODO
-
+VERSION

Makefile

@@ -10,6 +10,7 @@ include config.mk
 # Specific build targets and recipes below...
 # ===============================================================================
 
+
 # The targets to build by default if not otherwise specified to 'make'
 DEFAULT_TARGETS := static shared cio_ra.bin
 
@@ -34,7 +35,7 @@ api: $(DEFAULT_TARGETS)
 static: lib/novas.a
 
 .PHONY: shared
-shared: lib/novas.so
+shared: lib/novas.so lib/solsys1.so lib/solsys2.so
 
 .PHONY: solsys
 solsys: obj/solsys1.o obj/eph_manager.o obj/solsys2.o obj/jplint.o obj/solsys3.o obj/solsys-ephem.o
@@ -52,22 +53,43 @@ all: api solsys obj/novascon.o test coverage check
 
 .PHONY: clean
 clean:
-	rm -f object README-headless.md bin/cio_file
+	rm -f obj VERSION README-headless.md bin/cio_file
 	make -C test clean
 
 .PHONY: distclean
 distclean: clean
 	rm -f lib cio_ra.bin
 
-
 # Static library: novas.a
 lib/novas.a: $(OBJECTS) | lib
 	ar -rc $@ $^
 	ranlib $@
 
-# Shared library: novas.so
-lib/novas.so: $(SOURCES) | lib
-	$(CC) -o $@ $(CFLAGS) $^ -shared -fPIC
+# Shared library: novas.so -- same as supernovas.so except the builtin SONAME
+lib/novas.so: $(SOURCES) | lib VERSION
+	$(CC) -o $@ $(CFLAGS) $^ -shared -fPIC -Wl,-soname,libnovas.so.$(shell VERSION)
+
+# Shared library: supernovas.so -- same as novas.so except the builtin SONAME
+lib/supernovas.so: $(SOURCES) | lib VERSION
+	$(CC) -o $@ $(CFLAGS) $^ -shared -fPIC -Wl,-soname,libsupernovas.so.$(shell VERSION)
+
+
+# Shared library: solsys1.so (standalone solsys1.c functionality)
+lib/solsys1.so: BUILTIN_SOLSYS1 := 0
+lib/solsys1.so: $(SRC)/solsys1.c $(SRC)/eph_manager.c | lib VERSION
+	$(CC) -o $@ $(CFLAGS) $^ -shared -fPIC -Wl,-soname,libsolsys1.so.$(shell VERSION)
+
+# Shared library: solsys2.so (standalone solsys2.c functionality)
+lib/solsys2.so: BUILTIN_SOLSYS2 := 0
+lib/solsys2.so: $(SRC)/solsys2.c $(SRC)/jplint.f | lib VERSION
+	$(CC) -o $@ $(CFLAGS) $^ -shared -fPIC -Wl,-soname,libsolsys2.so.$(shell VERSION)
+
+VERSION: bin/version
+	$< >> $@
+
+.INTERMEDIATE: bin/version
+bin/version: $(SRC)/version.c | bin
+	$(CC) -o $@ -I$(INC) $<
 
 # CIO locator data
 .PHONY: cio_ra.bin

README.md

@@ -164,7 +164,8 @@ The SuperNOVAS distribution contains a GNU `Makefile`, which is suitable for com
 documentation, and tests, etc.) on POSIX systems such as Linux, BSD, MacOS X, or Cygwin or WSL. (At this point we do 
 not provide a similar native build setup for Windows, but speak up if you would like to add it yourself!)
 
-Before compiling the library take a look a `config.mk` and edit it as necessary for your needs, such as:
+Before compiling the library take a look a `config.mk` and edit it as necessary for your needs, or else define
+the necessary variables in the shell prior to invoking `make`. For example:
 
  - Choose which planet calculator function routines are built into the library (for example to provide 
    `earth_sun_calc()` set `BUILTIN_SOLSYS3 = 1`  and/or for `planet_ephem_provider()` set `BUILTIN_SOLSYS_EPHEM = 1`. 
@@ -182,13 +183,14 @@ Before compiling the library take a look a `config.mk` and edit it as necessary
    and you can provide a superior ephemeris reader implementation at runtime via the `set_ephem_provider()` call.
 
  - If you want to use the CIO locator binary file for `cio_location()`, you can specify the path to the binary file 
-   (e.g. `/usr/local/share/novas/cio_ra.bin`) on your system. (The CIO locator file is not at all necessary for the 
-   functioning of the library, unless you specifically require CIO positions relative to GCRS.)
+   (e.g. `/usr/local/share/novas/cio_ra.bin`) on your system e.g. by setting the `CIO_LOCATOR_FILE` shell variable
+   prior to calling `make`. (The CIO locator file is not at all necessary for the functioning of the library, unless 
+   you specifically require CIO positions relative to GCRS.)
 
  - If your compiler does not support the C11 standard and it is not GCC >=3.3, but provides some non-standard
    support for declaring thread-local variables, you may want to pass the keyword to use to declare variables as
    thread local via `-DTHREAD_LOCAL=...` added to `CFLAGS`. (Don't forget to enclose the string value in escaped
-   quotes.)
+   quotes in `config.mk`, or unescaped if defining the `THREAD_LOCAL` shell variable prior to invoking `make`.)
 
 Now you are ready to build the library:
 

config.mk

@@ -9,17 +9,25 @@
 SRC = src
 INC = include
 
-# Compiler options
-CFLAGS = -Os -Wall -I$(INC)
+
+# Base compiler options (if not defined externally...)
+CFLAGS ?= -Os -Wall 
+
+# Add include/ directory
+CFLAGS += -I$(INC)
+
 
 # Specific Doxygen to use if not the default one
-#DOXYGEN = /opt/bin/doxygen
+#DOXYGEN ?= /opt/bin/doxygen
+
 
 # Extra warnings (not supported on all compilers)
 #CFLAGS += -Wextra
 
+
 # For maximum compatibility with NOVAS C 3.1, uncomment the line below
-#CFLAGS += -DCOMPAT=1
+#COMPAT ?= 1
+
 
 # To make SuperNOVAS thread-safe, we use thread-local storage modifier
 # keywords. These were not standardized prior to C11. So while we automatically
@@ -28,9 +36,10 @@ CFLAGS = -Os -Wall -I$(INC)
 # explicitly here by passing the keyword via the THREAD_LOCAL definition
 #
 # E.g. 
-#CFLAGS += -DTHREAD_LOCAL=\"__thread\"
+#THREAD_LOCAL ?= __thread
 #or
-#CFLAGS += -DTHREAD_LOCAL=\"__declspec(thread)\"
+#THREAD_LOCAL ?= __declspec(thread)
+
 
 # You can set the default CIO locator file to use depending on where you 
 # installed it. By default, the library will assume 
@@ -40,51 +49,74 @@ CFLAGS = -Os -Wall -I$(INC)
 # availability, or in '$(HOME)/.local/share/novas' for user-specific 
 # installation.
 #
-#CFLAGS += -DDEFAULT_CIO_LOCATOR_FILE=\"/user/share/novas/cio_ra.bin\"
+#CIO_LOCATOR_FILE ?= /usr/share/novas/cio_ra.bin
+
 
 # Whether to build into the library planet_eph_manager() routines provided in 
 # solsys1.c. Because the default readeph implementation (readeph0.c) does not
 # provide useful functionality, we do not include solsys1.c in the build
 # by default.
-#BUILTIN_SOLSYS1 = 1
+#BUILTIN_SOLSYS1 ?= 1
+
 
 # Compile library with a default readeph() implementation for solsys1.c, which 
 # will be used only if the application does not define another implementation 
 # via calls to the to set_ephem_reader() function.
-DEFAULT_READEPH = $(SRC)/readeph0.c
+DEFAULT_READEPH ?= $(SRC)/readeph0.c
+
 
 # Whether to build into the library planet_jplint() routines provided in 
 # solsys2.c. Note, that if you choose to build in the functionality of 
 # solsys2.c you will need to provide a jplint_() implementation and its
 # dependencies such as pleph_() as well when linking your application.
 # Therefore, we do not include solsys2.c by default...
-#BUILTIN_SOLSYS2 = 1
+#BUILTIN_SOLSYS2 ?= 1
+
 
 # Whether to build into the library earth_sun_calc() routines provided in 
 # solsys3.c
-BUILTIN_SOLSYS3 = 1
+BUILTIN_SOLSYS3 ?= 1
+
 
 # Whether to build into the library planet_ephem_reader() routines provided in 
 # solsys3.c
-BUILTIN_SOLSYS_EPHEM = 1
+BUILTIN_SOLSYS_EPHEM ?= 1
+
 
 # Compile library with a default solarsystem() implementation. If you want to
 # use your library with your own solarsystem() implementation, you should
 # not set this option. In that case you must always provide a solarsystem()
 # implementation when linking your application against this library.
-DEFAULT_SOLSYS = 3
+DEFAULT_SOLSYS ?= 3
 
 
 # cppcheck options for 'check' target
 CHECKOPTS ?= --enable=performance,warning,portability,style --language=c \
             --error-exitcode=1
 
+
 # ============================================================================
 # END of user config section. 
 #
 # Below are some generated constants based on the one that were set above
 # ============================================================================
 
+# If the COMPAT variable is set to one, then force set compatibility mode
+ifeq ($(COMPAT),1)
+  CFLAGS += -DCOMPAT=1
+endif
+
+# If the CIO_LOCATOR_FILE variable is defined, the use its definition
+ifdef $(CIO_LOCATOR_FILE)
+  CFLAGS += -DDEFAULT_CIO_LOCATOR_FILE=\"$(CIO_LOCATOR_FILE)\"
+endif
+
+# If the THREAD_LOCAL variable was defined externally, use that definition to 
+# specify the thread local keyword to use. 
+ifdef $(THREAD_LOCAL)
+  CFLAGS += -DTHREAD_LOCAL=\"$(THREAD_LOCAL)"
+endif
+
 ifeq ($(DEFAULT_SOLSYS), 1) 
   BUILTIN_SOLSYS1 = 1
   CFLAGS += -DDEFAULT_SOLSYS=1