av_archive_metadata.c

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

#include <archive.h>
#include <archive_entry.h>

#include <libavformat/avformat.h>


int read_archive_packet(void * opaque, uint8_t *buf, int buf_size) {
    int data_read = (int)archive_read_data(opaque, buf, (size_t)buf_size);

    fprintf(stderr, "buf_size = %d, read %d\n", buf_size, data_read);


    if (data_read == 0)
        data_read = AVERROR_EOF;

    return data_read;
}

int64_t seek_archive_packet(void * opaque, int64_t offset, int whence) {
    fprintf(stderr, "test 2\n");
    struct archive * archive = opaque;

    return 0;
}

void read_av_format(struct archive * archive, struct archive_entry * entry) {
    /* Setup buffers */
    const int buf_size = 32 * 1024;

    /* Create our AVIOContext stream */
    AVIOContext * av_io_context = avio_alloc_context(
            malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE),
            buf_size,
            0,
            archive,
            read_archive_packet,
            0,
            seek_archive_packet
    );

    /* Allocate our format context */
    AVFormatContext* pCtx = avformat_alloc_context();

    pCtx->pb = av_io_context;
    pCtx->flags = AVFMT_FLAG_CUSTOM_IO;

    /* Now we need to probe for input format */

    AVInputFormat * avFormat;

    if (av_probe_input_buffer(av_io_context, &avFormat, archive_entry_pathname(entry), NULL, 0, buf_size) != 0) {
        goto read_av_format_free;
    }

    pCtx->iformat = avFormat;

    if (avformat_open_input(&pCtx, "", avFormat, 0) != 0)
        goto read_av_format_free;


    avformat_find_stream_info(pCtx, 0);

read_av_format_free:
    free(pCtx->pb->buffer);
    avformat_close_input(&pCtx);
}

void read_archive(struct archive * open_archive) {
    struct archive_entry *entry;

    while (archive_read_next_header(open_archive, &entry) == ARCHIVE_OK) {
        printf("file = %s\n", archive_entry_pathname(entry));
        
        read_av_format(open_archive, entry);
    }
}

int main(int argc, char *argv[]) {
    const char * path = NULL;
    struct archive * archive = NULL;

    for (int a = 1; a < argc; a++) {
        path = argv[a];

        if (access(path, R_OK) < 0) {
            fprintf(stderr, "File %s does not exist\n", path);
            break;
        }

        archive = archive_read_new();

        if (archive != NULL) {
            if ((archive_read_support_filter_all(archive) != ARCHIVE_OK) ||
                (archive_read_support_format_all(archive) != ARCHIVE_OK)) {

                archive_read_free(archive);

                fprintf(stderr, "Failed to setup libarchive for reading\n");

                archive = NULL;
            }
        }

        if (archive != NULL) {
            if (archive_read_open_filename(archive, path, 128) == ARCHIVE_OK) {
                read_archive(archive);
            }

            archive_read_free(archive);
        }
    }
    return 0;
}