正确释放其他功能中的内存空间

Edit : the problem isn't what I thought it was, check answers before reading my (long) question will spare you some time.

编辑：问题不是我想的那样，在阅读我的（长期）问题之前检查答案将为您节省一些时间。

i've been valgrinding my little C project for school (basically a language detector), but there's a set of pointers I still have problems with according to valgrind. I think the problem is classic, it could be resumed in : How should I free a variable i malloced in another function when I (think I) have no choice ?

我一直在学习我的小C项目（基本上是语言检测器），但根据valgrind的说法，我仍然有一些指针。我认为问题是经典的，它可以恢复：当我（我想）别无选择时，我应该如何释放我在另一个函数中进行malloced的变量？

Here are the relevant parts of the two functions which cause me this problem. Basically, get_modeles_names gathers the filenames holding the right substring within them from my "collection" file; then det_langue is processing them. Here is get_modeles_names :

以下是导致这个问题的两个函数的相关部分。基本上，get_modeles_names从我的“集合”文件中收集包含其中正确子字符串的文件名;然后det_langue正在处理它们。这是get_modeles_names：

    void get_modeles_names(int mode, char ** modeles)
{
        FILE * collection = get_collection_file();
        int i = 0;
        char * line = NULL;
        size_t size = 0;

        while (getline(&line, &size, collection) != -1) {
            if (strstr(line, entete)) {
                modeles[i] = (char*) malloc(strlen(line) * sizeof (char));
                modeles[i] = line;

                modeles[i][strlen(modeles[i]) - 1] = '\0';
                //replaces the final '\n' by '\0'

                i++;
                line = NULL;
            }
        }

        if (line)
            free(line);

        fclose(collection);
}

And here is det_langue :

这是det_langue：

void det_langue(char * w)
{
    int nb_modele = nb_modeles();

    char ** modeles = (char **) malloc(nb_modele * sizeof (char *));
    get_modeles_names(mode, modeles);

    double * resultats = (double *) malloc(nb_modele * sizeof (double));

    int i;
    for (i = 0; i < nb_modele; i++) {
        resultats[i] = calculate_result (w, modeles[i]);
        }
    }

    for (i = 0; i < nb_modele; i++) {
        free(modeles[i]);
    }
    free(modeles);
    free(resultats);
}

As you can see, i malloc my char ** modeles in det_langue to the right size (i am confident the nb_modeles function works fine) , then i malloc each element of modeles in get_modeles_names ; but since i need to process them later on, i can't free them (or don't know how) where i malloced them, i free them later, in the end of det_langue. I would think it's allright, but here's the output of valgrind --leak-check=full ./projet -d pomme -m 1

正如你所看到的，我在det_langue中将我的char **模型malloc到正确的大小（我确信nb_modeles函数工作正常），然后我在get_modeles_names中malloc每个元素元素;但是因为我需要稍后处理它们，所以我无法释放它们（或者不知道如何）我在哪里使用它们，我们在det_langue结束时释放它们。我认为这没关系，但这里是valgrind的输出--leak-check = full ./projet -d pomme -m 1

==30547== Command: ./projet -d pomme -m 1
==30547== 
pomme -> french
==30547== 
==30547== HEAP SUMMARY:
==30547==     in use at exit: 113 bytes in 4 blocks
==30547==   total heap usage: 40 allocs, 36 frees, 30,906 bytes allocated
==30547== 
==30547== 113 bytes in 4 blocks are definitely lost in loss record 1 of 1
==30547==    at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==30547==    by 0x40163E: get_modeles_names (gestion_collection_modeles.c:120)
==30547==    by 0x401919: det_langue (det_langue.c:12)
==30547==    by 0x40189E: main (Main.c:76)
==30547== 
==30547== LEAK SUMMARY:
==30547==    definitely lost: 113 bytes in 4 blocks
==30547==    indirectly lost: 0 bytes in 0 blocks
==30547==      possibly lost: 0 bytes in 0 blocks
==30547==    still reachable: 0 bytes in 0 blocks
==30547==         suppressed: 0 bytes in 0 blocks
==30547== 
==30547== For counts of detected and suppressed errors, rerun with: -v
==30547== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)

Line 120 is in get_modeles_names, it's : modeles[i] = (char*) malloc(strlen(line) * sizeof (char)); Also, the size of modeles is 4, which explains for the 40 allocs but only 36 frees. Also, if I go berserk and simply free modeles in the get_modeles_names function, my program obviously seg_faults, since the data i'm supposed to process don't exist anymore.

第120行在get_modeles_names中，它是：modeles [i] =（char *）malloc（strlen（line）* sizeof（char））;此外，模型的大小为4，这解释了40个分配但只有36个释放。另外，如果我在get_modeles_names函数中进行狂暴和简单的免费模型，我的程序显然是seg_faults，因为我应该处理的数据不再存在。

I've googled around, but couldn't find any question already asked which would answer mine .... any idea ?

我已经用Google搜索了，但是找不到任何已经问过的问题，哪个会回答我的....有什么想法吗？

Edit : the mem_leak was the one described in solution, but there is another as soon as it's solved : line leaks, which is solved by moving

编辑：mem_leak是解决方案中描述的那个，但是一旦解决就会有另一个：线路泄漏，这是通过移动解决的

if(line)
    free(line);

within the while loop.

在while循环中。

2 个解决方案

#1

I see the following problem:

我看到以下问题：

        if (strstr(line, entete)) {
            modeles[i] = (char*) malloc(strlen(line) * sizeof (char));
            modeles[i] = line;

Here, you first allocate memory with malloc and save the pointer to it in modeles[i] but then you overwrite the pointer with line. If you want to copy the contents of line, then use strcpy.

在这里，首先使用malloc分配内存并在modeles [i]中保存指向它的指针，然后用线覆盖指针。如果要复制行的内容，请使用strcpy。

Note that you do not allocate enough memory for the strcpy of line: you forget the terminating null character. It should be:

请注意，您没有为strcpy of line分配足够的内存：您忘记了终止空字符。它应该是：

            modeles[i] = malloc(strlen(line) + 1);

or:

要么：

            int len= strlen(line);
            line[len-2] = '\0';
            modeles[i] = malloc(len);
            strcpy(modeles[i], line);

.. and sizeof(char) is not needed because sizeof(char) is always 1.

因为sizeof（char）始终为1，所以不需要..和sizeof（char）。

#2

The problem is

问题是

modeles[i] = line;

that is just replacing the pointer to the memory you malloc'd You want a strcpy() there:

这只是替换指向malloc的内存的指针你想要一个strcpy（）：

strcpy(models[i], line);

#1