c - 在命令行和 Makefile 中定义宏,在 Linux 上使用 gcc 工作,编写 C 代码

标签 c linux gcc makefile

我有一个名为:Makefile 的文件和一个 main.c 文件 我正在 main.c 文件中执行下一段代码

int main(int argc, char *argv[])
{

    //if 0 then it is default scheduling which is Round Robin.
    //if 1 then the scheduling will be Round Robin.
    //if 2 then the scheduling will be Priority based.
    //if 3 then both scheduling are acceptable, and we decide to use Round Robin.
    int scheduling = 0; 
    #ifdef SCHED_RR
            printf("SCHED_RR is defined\n");
            #ifdef SCHED_PB
                    printf("and also SCHED_PB is defined\n");
                    scheduling = 3;
            #else
                    scheduling = 1;
            #endif
    #elseif SCHED_PB
            printf("SCHED_PB is defined\n")
            scheduling = 2;
    #endif

    printf("the number of the scheduling is %d\n",scheduling);
    printf("bye bye\n");

    return 0;

}//main

如您所见,我正在检查是否已定义宏以及定义了哪个宏。 现在我想用我的 Makefile 执行下一个命令行来运行程序

make some_var=SCHED_RR

这个伪命令(因为我不知道该怎么做)是为了预定义宏 SCHED_RR 我也希望能够编写命令

make some_var=SCHED_PB

make some_var1=SCHED_RR some_var2=SCHED_PB

最后一个是针对有人想预定义两个调度的情况

现在我的问题是:我不知道如何以及在哪里将它写入我的 Makefile 以及如何在命令行中编写它?

这是我的 Makefile,这当然表明我的真实程序更大 那么我应该在这个 make 文件中添加什么?

OBJS = \
    bio.o\
    console.o\
    exec.o\
    file.o\
    fs.o\
    ide.o\
    ioapic.o\
    kalloc.o\
    kbd.o\
    lapic.o\
    log.o\
    main.o\
    mp.o\
    picirq.o\
    pipe.o\
    proc.o\
    spinlock.o\
    string.o\
    swtch.o\
    syscall.o\
    sysfile.o\
    sysproc.o\
    timer.o\
    trapasm.o\
    trap.o\
    uart.o\
    vectors.o\
    vm.o\



# Cross-compiling (e.g., on Mac OS X)
#TOOLPREFIX = i386-jos-elf-

# Using native tools (e.g., on X86 Linux)
#TOOLPREFIX = 

# Try to infer the correct TOOLPREFIX if not set
ifndef TOOLPREFIX
TOOLPREFIX := $(shell if i386-jos-elf-objdump -i 2>&1 | grep '^elf32-i386$$' >/dev/null 2>&1; \
    then echo 'i386-jos-elf-'; \
    elif objdump -i 2>&1 | grep 'elf32-i386' >/dev/null 2>&1; \
    then echo ''; \
    else echo "***" 1>&2; \
    echo "*** Error: Couldn't find an i386-*-elf version of GCC/binutils." 1>&2; \
    echo "*** Is the directory with i386-jos-elf-gcc in your PATH?" 1>&2; \
    echo "*** If your i386-*-elf toolchain is installed with a command" 1>&2; \
    echo "*** prefix other than 'i386-jos-elf-', set your TOOLPREFIX" 1>&2; \
    echo "*** environment variable to that prefix and run 'make' again." 1>&2; \
    echo "*** To turn off this error, run 'gmake TOOLPREFIX= ...'." 1>&2; \
    echo "***" 1>&2; exit 1; fi)
endif

# If the makefile can't find QEMU, specify its path here
#QEMU = 

# Try to infer the correct QEMU
ifndef QEMU
QEMU = $(shell if which qemu > /dev/null; \
    then echo qemu; exit; \
    else \
    qemu=/Applications/Q.app/Contents/MacOS/i386-softmmu.app/Contents/MacOS/i386-softmmu; \
    if test -x $$qemu; then echo $$qemu; exit; fi; fi; \
    echo "***" 1>&2; \
    echo "*** Error: Couldn't find a working QEMU executable." 1>&2; \
    echo "*** Is the directory containing the qemu binary in your PATH" 1>&2; \
    echo "*** or have you tried setting the QEMU variable in Makefile?" 1>&2; \
    echo "***" 1>&2; exit 1)
endif


CC = $(TOOLPREFIX)gcc
AS = $(TOOLPREFIX)gas
LD = $(TOOLPREFIX)ld
OBJCOPY = $(TOOLPREFIX)objcopy
OBJDUMP = $(TOOLPREFIX)objdump
#CFLAGS = -fno-pic -static -fno-builtin -fno-strict-aliasing -O2 -Wall -MD -ggdb -m32 -Werror -fno-omit-frame-pointer
CFLAGS = -fno-pic -static -fno-builtin -fno-strict-aliasing -Wall -MD -ggdb -m32 -Werror -fno-omit-frame-pointer
CFLAGS += $(shell $(CC) -fno-stack-protector -E -x c /dev/null >/dev/null 2>&1 && echo -fno-stack-protector)
ASFLAGS = -m32 -gdwarf-2 -Wa,-divide
# FreeBSD ld wants ``elf_i386_fbsd''
LDFLAGS += -m $(shell $(LD) -V | grep elf_i386 2>/dev/null)

xv6.img: bootblock kernel fs.img
    dd if=/dev/zero of=xv6.img count=10000
    dd if=bootblock of=xv6.img conv=notrunc
    dd if=kernel of=xv6.img seek=1 conv=notrunc

xv6memfs.img: bootblock kernelmemfs
    dd if=/dev/zero of=xv6memfs.img count=10000
    dd if=bootblock of=xv6memfs.img conv=notrunc
    dd if=kernelmemfs of=xv6memfs.img seek=1 conv=notrunc

bootblock: bootasm.S bootmain.c
    $(CC) $(CFLAGS) -fno-pic -O -nostdinc -I. -c bootmain.c
    $(CC) $(CFLAGS) -fno-pic -nostdinc -I. -c bootasm.S
    $(LD) $(LDFLAGS) -N -e start -Ttext 0x7C00 -o bootblock.o bootasm.o bootmain.o
    $(OBJDUMP) -S bootblock.o > bootblock.asm
    $(OBJCOPY) -S -O binary -j .text bootblock.o bootblock
    ./sign.pl bootblock

entryother: entryother.S
    $(CC) $(CFLAGS) -fno-pic -nostdinc -I. -c entryother.S
    $(LD) $(LDFLAGS) -N -e start -Ttext 0x7000 -o bootblockother.o entryother.o
    $(OBJCOPY) -S -O binary -j .text bootblockother.o entryother
    $(OBJDUMP) -S bootblockother.o > entryother.asm

initcode: initcode.S
    $(CC) $(CFLAGS) -nostdinc -I. -c initcode.S
    $(LD) $(LDFLAGS) -N -e start -Ttext 0 -o initcode.out initcode.o
    $(OBJCOPY) -S -O binary initcode.out initcode
    $(OBJDUMP) -S initcode.o > initcode.asm

kernel: $(OBJS) entry.o entryother initcode kernel.ld
    $(LD) $(LDFLAGS) -T kernel.ld -o kernel entry.o $(OBJS) -b binary initcode entryother
    $(OBJDUMP) -S kernel > kernel.asm
    $(OBJDUMP) -t kernel | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernel.sym

# kernelmemfs is a copy of kernel that maintains the
# disk image in memory instead of writing to a disk.
# This is not so useful for testing persistent storage or
# exploring disk buffering implementations, but it is
# great for testing the kernel on real hardware without
# needing a scratch disk.
MEMFSOBJS = $(filter-out ide.o,$(OBJS)) memide.o
kernelmemfs: $(MEMFSOBJS) entry.o entryother initcode fs.img
    $(LD) $(LDFLAGS) -Ttext 0x100000 -e main -o kernelmemfs entry.o  $(MEMFSOBJS) -b binary initcode entryother fs.img
    $(OBJDUMP) -S kernelmemfs > kernelmemfs.asm
    $(OBJDUMP) -t kernelmemfs | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > kernelmemfs.sym

tags: $(OBJS) entryother.S _init
    etags *.S *.c

vectors.S: vectors.pl
    perl vectors.pl > vectors.S

ULIB = ulib.o usys.o printf.o umalloc.o uthread.o

_%: %.o $(ULIB)
    $(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $@ $^
    $(OBJDUMP) -S $@ > $*.asm
    $(OBJDUMP) -t $@ | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $*.sym

_forktest: forktest.o $(ULIB)
    # forktest has less library code linked in - needs to be small
    # in order to be able to max out the proc table.
    $(LD) $(LDFLAGS) -N -e main -Ttext 0 -o _forktest forktest.o ulib.o usys.o
    $(OBJDUMP) -S _forktest > forktest.asm

mkfs: mkfs.c fs.h
    gcc -DVarName=$(VarName) -m32 -Werror -Wall -o mkfs mkfs.c

UPROGS=\
    _cat\
    _echo\
    _forktest\
    _grep\
    _init\
    _kill\
    _ln\
    _ls\
    _mkdir\
    _rm\
    _sh\
    _stressfs\
    _usertests\
    _wc\
    _zombie\
    _main\

fs.img: mkfs README $(UPROGS)
    ./mkfs fs.img README $(UPROGS)

-include *.d

clean: 
    rm -f *.tex *.dvi *.idx *.aux *.log *.ind *.ilg \
    *.o *.d *.asm *.sym vectors.S bootblock entryother \
    initcode initcode.out kernel xv6.img fs.img kernelmemfs mkfs \
    .gdbinit \
    $(UPROGS)

# make a printout
FILES = $(shell grep -v '^\#' runoff.list)
PRINT = runoff.list runoff.spec README toc.hdr toc.ftr $(FILES)

xv6.pdf: $(PRINT)
    ./runoff
    ls -l xv6.pdf

print: xv6.pdf

# run in emulators

bochs : fs.img xv6.img
    if [ ! -e .bochsrc ]; then ln -s dot-bochsrc .bochsrc; fi
    bochs -q

# try to generate a unique GDB port
GDBPORT = $(shell expr `id -u` % 5000 + 25000)
# QEMU's gdb stub command line changed in 0.11
QEMUGDB = $(shell if $(QEMU) -help | grep -q '^-gdb'; \
    then echo "-gdb tcp::$(GDBPORT)"; \
    else echo "-s -p $(GDBPORT)"; fi)
ifndef CPUS
CPUS := 1
endif
QEMUOPTS = -hdb fs.img xv6.img -smp $(CPUS) -m 512 $(QEMUEXTRA)

qemu: fs.img xv6.img
    $(QEMU) -serial mon:stdio $(QEMUOPTS)

qemu-memfs: xv6memfs.img
    $(QEMU) xv6memfs.img -smp $(CPUS)

qemu-nox: fs.img xv6.img
    $(QEMU) -nographic $(QEMUOPTS)

.gdbinit: .gdbinit.tmpl
    sed "s/localhost:1234/localhost:$(GDBPORT)/" < $^ > $@

qemu-gdb: fs.img xv6.img .gdbinit
    @echo "*** Now run 'gdb'." 1>&2
    $(QEMU) -serial mon:stdio $(QEMUOPTS) -S $(QEMUGDB)

qemu-nox-gdb: fs.img xv6.img .gdbinit
    @echo "*** Now run 'gdb'." 1>&2
    $(QEMU) -nographic $(QEMUOPTS) -S $(QEMUGDB)

# CUT HERE
# prepare dist for students
# after running make dist, probably want to
# rename it to rev0 or rev1 or so on and then
# check in that version.

EXTRA=\
    mkfs.c ulib.c user.h cat.c echo.c forktest.c grep.c kill.c\
    ln.c ls.c mkdir.c rm.c stressfs.c usertests.c wc.c zombie.c\
    printf.c umalloc.c main.c\
    README dot-bochsrc *.pl toc.* runoff runoff1 runoff.list\
    .gdbinit.tmpl gdbutil\

dist:
    rm -rf dist
    mkdir dist
    for i in $(FILES); \
    do \
        grep -v PAGEBREAK $$i >dist/$$i; \
    done
    sed '/CUT HERE/,$$d' Makefile >dist/Makefile
    echo >dist/runoff.spec
    cp $(EXTRA) dist

dist-test:
    rm -rf dist
    make dist
    rm -rf dist-test
    mkdir dist-test
    cp dist/* dist-test
    cd dist-test; $(MAKE) print
    cd dist-test; $(MAKE) bochs || true
    cd dist-test; $(MAKE) qemu

# update this rule (change rev#) when it is time to
# make a new revision.
tar:
    rm -rf /tmp/xv6
    mkdir -p /tmp/xv6
    cp dist/* dist/.gdbinit.tmpl /tmp/xv6
    (cd /tmp; tar cf - xv6) | gzip >xv6-rev5.tar.gz

.PHONY: dist-test dist

谢谢

最佳答案

你需要的是

make -e VarName=VarValue

这会将 VarName 导出到 makefile 中,您可以在其中将其用作 gcc 编译语句中的 $(VarName)。

因此,在 makefile 中它将是

gcc -DVarName=$(VarName) -c your_source.c -o your_obj.o

对于“#ifdef”的情况,您要么必须将其更改为“#if”,要么使用:

make -e SCHED_PR=1

在生成文件中

ifeq ($(SCHED_PR), 1)
mkfs: .....
    gcc -DSCHED_PR=1  ....
else
mkfs: .....
    gcc ....
endif

在.c文件中

#if SCHED_PR

...

关于c - 在命令行和 Makefile 中定义宏,在 Linux 上使用 gcc 工作,编写 C 代码,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10590502/

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