env_arm

import os

CORE = "cortex-m4"
OPTIMIZATION_LEVEL = "s"


"""
Define build environment

References:
- https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html
"""
env_arm = Environment(
    ENV=os.environ,
    tools=["mingw"],
    CC="arm-none-eabi-gcc",
    OBJCOPY="arm-none-eabi-objcopy",
    OBJDUMP="arm-none-eabi-objdump",
    SIZE="arm-none-eabi-size",
    CFLAGS=[
        "-std=c99",
        "-fmessage-length=0",
        "-ffunction-sections",
        "-fdata-sections",
    ],
    ASFLAGS=[],
    LINKFLAGS=[
        "-nostartfiles",
        "-specs=nano.specs",
        "-u", "_printf_float",
        "-u", "_scanf_float",
        "-specs=nosys.specs",
        "-Wl,--gc-sections",
    ],
    CPPPATH=[],
    CPPDEFINES=[],
    LIBS=[
        "m",
    ]
)

""" Define additional flags """
COMMON_FLAGS = [
    "-O{}".format(OPTIMIZATION_LEVEL),
    "-mcpu={}".format(CORE),
    "-mthumb",
    "-mfloat-abi=hard",
    "-mfpu=auto",
    "-Wall",
    "-g",
    "-pipe",
]
env_arm["CFLAGS"].extend(COMMON_FLAGS)
env_arm["LINKFLAGS"].extend(COMMON_FLAGS)


"""
Define builders

References:
- https://sourceware.org/binutils/docs/binutils/objcopy.html
- https://sourceware.org/binutils/docs/binutils/objdump.html
- https://sourceware.org/binutils/docs/binutils/size.html
"""
def objcopy_generator(source, target, env, for_signature):
    """
    :raise: KeyError if target format is not supported.
    """
    file_basename, file_ext = os.path.splitext(target[0].name)
    file_ext = file_ext.lstrip(".")  # Strip leading '.' if any (i.e. ".hex" -> "hex")
    ext_fmt_map = {
        "bin": "binary",
        "hex": "ihex",
    }
    return "$OBJCOPY -O {} $SOURCE $TARGET".format(ext_fmt_map[file_ext])


env_arm["BUILDERS"]["Objcopy"] = Builder(generator=objcopy_generator)
env_arm["BUILDERS"]["Objdump"] = Builder(action="$OBJDUMP --source --all-headers --demangle --line-numbers --wide $SOURCE > $TARGET")
env_arm["BUILDERS"]["Size"] = Builder(action="$SIZE --format=berkeley $SOURCE")

Export("env_arm")