从函数中获取结构

Question

我希望从函数中返回带有多维数据的结构。其思想是:收集函数中的结构信息，然后将虚拟结构分配给结构patches，然后在不同的函数中使用patches信息并对其进行循环。

这就是我所拥有的。我怎么才能做好这件事？

struct patchdata {
    char* version;
    char* size;
    char* compatible;
};

int ourfunction(struct patchdata* patches) {
    size_t count = 12;

    struct patchdata tmp[count];

    tmp[0] = "Version 1.0";
    tmp[1] = "Version 2.0";
    tmp[2] = "Version 3.0";

    if (patches) {
        memcpy(patches, &tmp, sizeof(*patches));
    }
}

struct patchdata patchstruct;

int main()
{
    ourfunction(&patchstruct);

    printf("Test: %s\n", patchstruct[0].version);

    return 0;
}

Answer 1

一种更简单的方法是将struct字段定义为：

#include <stdio.h>

struct patchdata {
    char *version;
    char *size;
    char *compatible;
};

int ourfunction(struct patchdata *patches) {
    if (patches) {
        // assuming patches points to an array of at least 3 structures

        patches[0].version = "Version 1.0";
        patches[0].size = NULL;
        patches[0].compatible = NULL;

        patches[1].version = "Version 2.0";
        patches[1].size = NULL;
        patches[1].compatible = NULL;

        patches[2].version = "Version 3.0";
        patches[2].size = NULL;
        patches[2].compatible = NULL;
        return 0;
    } else {
        return -1;
    }
}

int main() {
    struct patchdata patchstruct[3];

    ourfunction(patchstruct);

    printf("Test: %s\n", patchstruct[0].version);

    return 0;
}