utarray question: pre-allocated itens

[silvioprog]

Hello dudes,

Consider the following code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "utarray.h"

struct upload {
    const char *filename;
    FILE *stream;
};

static void upload_init(void *p) {
    struct upload *up = p;
    up->stream = fopen(up->filename, "r");
}

static void upload_dtor(void *p) {
    struct upload *up = p;
    fclose((up)->stream);
    free(up);
}

UT_icd upload_icd = {sizeof(struct upload), &upload_init, NULL, &upload_dtor};

int main() {
    char line[10]; // <- just for tests
    struct upload *up, *p;
    UT_array *ups;
    utarray_new(ups, &upload_icd);

    // upload 1
    up = malloc(sizeof(struct upload));
    up->filename = "foo.txt";
    utarray_push_back(ups, up);

    // upload 2
    up = malloc(sizeof(struct upload));
    up->filename = "bar.txt";
    utarray_push_back(ups, up);

    for (p = (struct upload *) utarray_front(ups); p != NULL; p = (struct upload *) utarray_next(ups, p)) {
        printf("filename: %s\n", p->filename);
        while (fgets(line, sizeof(line), up->file))
            printf("content: %s\n", line);
    }

    utarray_free(ups);
    return 0;
}

In the real scenario "up" if allocated in a scope and its reference reused in other scopes, so its life cycle must be managed outside utarray.

Therefore, how do I use utarray with pre-allocated itens? (I took a look its sources and can't find any utarray_push_back_ptr :-/)

Thank you!

--

Silvio Clécio

[silvioprog]

Oops, sorry. It seems I need a utlist instead of utarray. I'm going to check it ... ^^'

--

Silvio Clécio

[silvioprog]

Solved. Please skip my previous e-mails and sorry the noise. :-)

Using utlist (thanks this awesome structure!):

#include <stdio.h>
#include <stdlib.h>
#include "utlist.h"

struct upload {
    const char *filename;
    FILE *stream;

    struct upload *next;
};

typedef void (*uploads_foreach_callback)(void *cls, struct upload *item);

struct upload *uploads_add(struct upload **list, const char *filename) {
    struct upload *item;
    if (NULL == list)
        return NULL;
    item = malloc(sizeof(struct upload));
    if (NULL == item)
        return NULL;
    item->filename = filename;
    item->stream = fopen(item->filename, "r");
    LL_APPEND(*list, item);
    return item;
}

void uploads_foreach(struct upload *list, uploads_foreach_callback callback, void *callback_cls) {
    struct upload *item;
    if (NULL != list && NULL != callback)
        LL_FOREACH(list, item) {
            callback(callback_cls, item);
        }
}

void uploads_cleanup(struct upload *list) {
    struct upload *item, *tmp;
    if (NULL != list)
        LL_FOREACH_SAFE(list, item, tmp) {
            LL_DELETE(list, item);
            fclose(item->stream);
            free(item);
        }
}

/* example */

static void example_uploads_foreach(void *cls, struct upload *item) {
    char line[1024];
    printf("filename: %s\n", item->filename);
    while (fgets(line, sizeof(line), item->stream))

        printf("content: %s\n", line);
}

int main() {
    struct upload *list = NULL;
    // upload 1
    uploads_add(&list, "foo.txt"); // up = upload_add: finally I can use the "up" reference outside the list! :-)
    // upload 2
    uploads_add(&list, "bar.txt");
    uploads_foreach(list, &example_uploads_foreach, NULL);
    uploads_cleanup(list);
    return 0;
}

--

Silvio Clécio