包含在多个源文件中的头文件中的 C 预处理器 #error

Question

I have two source files, main.c and datamgr.c - and two header files, config.h and datamgr.h The testing system we're using expects these files, and only these files.

main.c:

#include "datamgr.h"
#include "config.h"

int main() {
    custom_type a = 1;

    a = foo();
    return 0;
}

datamgr.c:

#include "datamgr.h"
#include "config.h"

custom_type foo() {
    custom_type a = 1;
    return a;
}

datamgr.h:

#ifndef DATAMGR_H
#define DATAMGR_H

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>

custom_type foo();

#endif

config.h:

#ifndef CONFIG_H
#define CONFIG_H

#ifndef SET_MAX_TEMP
#error "Max temperature not set."
#endif

#ifndef SET_MIN_TEMP
#error "Max temperature not set."
#endif

typedef custom_type uint16_t

#endif

Now, the problem is that I can only define SET_MAX_TEMP and SET_MIN_TEM P in main.c, but both main.c and datamgr.c need both the header files. So if I leave them undefined in datamgr.c I get a compiler error. However, if I do define them in datamgr.c and later overwrite them in main.c, I get a different compiler error.

Please, any assistance as to how to get this horrible setup to work would be greatly appreciated.

Answer 1

您可以在编译时直接传递这些define ：

gcc -DSET_MAX_TEMP -DSET_MIN_TEMP <your files>

Answer 2

In datamgr.c do:

#define SET_MAX_TEMP
#define SET_MIN_TEMP

#include "datamgr.h"
#include "config.h"

#undef SET_MAX_TEMP
#undef SET_MIN_TEMP

Answer 3

In a comment, you said:

Because main.c is the file that our testing system uses to implement the test scenarios.

In that case, make sure that the testing system defines those macros in the command line of the compiler for every file being compiled.