# Makefile 4: Using implicit rules

###################################
# Overriding default macros

# For compiling C files
CC = gcc
CFLAGS = -Wall -g

# For compiling C++ files
CXX = g++
CXXFLAGS = -Wall -g

# For linking
LDFLAGS = 

# For creating a library
AR = ar
ARFLAGS = rc

# End of defaults
###################################


###################################
# Let's define sone additional variables

RANLIB = ranlib

PROGRAMS = main-stack main-queue 

MAIN_STACK_DEPS = main-stack.o stack.o

LIB_DEPS  = queue.o stack.o
LIB = libdata.a

MAIN_QUEUE_DEPS = main-queue.o $(LIB)
MAIN_QUEUE_LIBS = -L. -ldata

###################################

all: $(PROGRAMS)

# Using pattern rules
# The order of the following two pattern rules is important 
# First pattern rules
main-%.o: main-%.c %.h
	$(CC) $(CFLAGS) -c $<

# Second pattern rule
%.o: %.c %.h
	$(CC) $(CFLAGS) -c $<

libdata.a: $(LIB_DEPS)
	$(AR) $(ARFLAGS) $@ $(LIB_DEPS)
	$(RANLIB) $@

# Thanks to implicit rules, we can often avoid 
# writing any rule at all or we can specify the 
# dependencies only and let make figure out what to do with them
main-stack: $(MAIN_STACK_DEPS)

main-queue: $(MAIN_QUEUE_DEPS)
	$(CC) $(LDFLAGS) -o $@ $<  $(MAIN_QUEUE_LIBS)

clean:
	rm -f *.o $(PROGRAMS) $(LIB)