Bake

Bake is a command-line utility that implements a subset of the features of GNU Make. This project was written for the CITS2002 UWA unit in 2018.

Information on writing bakefiles, building bake and running bake can be found below, along with an example Bakefile.

Example Bakefile

# The command we want to use to compile our binaries
C99 = cc -std=c99 -Wall -pedantic -Werror

# Where our source and build files are located
SRC = src
BUILD = build

# The target and source files of the program
OBJECTS = $(BUILD)/buffer.o $(BUILD)/main.o
SOURCES = $(SRC)/buffer.h $(SRC)/buffer.c \
          $(SRC)/main.h $(SRC)/main.c

#
# Compile all sources into the $(BUILD) folder
#
bake: $(OBJECTS) $(SOURCES)
	$(C99)  -o $(BUILD)/buffer.o  -c $(SRC)/buffer.c
	$(C99)  -o $(BUILD)/main.o    -c $(SRC)/main.c

	$(C99)  -o bake  $(OBJECTS)
	@echo " === PROGRAM BUILT === "

Variables

Variables can be used to define a value once, which you can then re-use later in your Bakefile.

Defining a variable:

<IDENTIFIER> = <VALUE>

Using a variable:

$(<IDENTIFIER>)

Targets

Targets are used to represent files built by your Bakefile.

The modification time of the target is found as the modification time of <FILE>. If the file does not exist on disk, then the target will always be ran.

Defining a target:

<FILE> : <DEPENDENCY-1 [DEPENDENCY-2 ...]>

Dependencies

Dependencies define when targets should be rebuilt.

If a target has no dependencies, it will always be rebuilt.

File Dependencies: Files that when modified, signal that this target needs to be rebuilt.

<FILE-NAME>

URL Dependencies: URLs that when modified, signal that this target needs to be rebuilt. The modification date of URLs is found from their Last-Modified header.

http://<URL> or https://<URL> or file://<FILE>

Target Dependencies: Targets that when rebuilt, signal that this target should also be rebuilt.

<TARGET-FILE>

Action Lines

The commands that are ran to rebuild the target. Modifiers can be placed before the commands to adjust how they are executed.

Available Modifiers:

• '@' = Do not print the commands before executing them.
• ' - ' = Ignore whether the command was successful, and carry on as usual.

Each action line should follow a target definition, and be prefixed by a tab character.

my_target : file1 file2
	-rm -f out.o
	$(C99) -o out.o  -c in.c
	@echo " === Success === "

Comments

Empty lines, or lines starting with '#' will be ignored during parsing.

# This is a comment.

# ^ and that empty line's valid too.

Building Bake

The GNU make command can be used to build Bake:

cd Bake
make

Or, once you have a version of bake compiled:

cd Bake
./bake

Bake's Command-Line Options

There are several options that can be specified when executing bake.

• -C <dir> = Change the directory to <dir> before commencing execution.

• -f <file> = Execute <file> instead of the default Bakefile or bakefile.

• -i = Run all commands ignoring whether they were successful.

• -n = Print all commands that would have been executed, without actually executing them.

• -p = Print out the parsed bakefile with all variables expanded.

• -s = Do not print the commands before they are executed.

An optional target parameter can also be specified after all options, which dictates the target to be ran. If no target is specified, the first target in the file will be ran.

./bake [OPTIONS] [TARGET]