vgmstream/src/meta/maxis_xa.c

#include "meta.h"
#include "../util.h"

/* Maxis XA - found in Sim City 3000 (PC) */
VGMSTREAM * init_vgmstream_maxis_xa(STREAMFILE *streamFile) {
    VGMSTREAM * vgmstream = NULL;
    off_t start_offset;
    int loop_flag, channel_count, i;

    /* check extension, case insensitive */
    if (!check_extensions(streamFile,"xa"))
        goto fail;

    /* check header */
    if ((read_32bitBE(0x00,streamFile) != 0x58414900) && /* "XAI\0" */
        (read_32bitBE(0x00,streamFile) != 0x58414A00))   /* "XAJ\0" (some odd song uses this, no apparent diffs) */
        goto fail;

    loop_flag = 0;
    channel_count = read_16bitLE(0x0A,streamFile);

    /* build the VGMSTREAM */
    vgmstream = allocate_vgmstream(channel_count,loop_flag);
    if (!vgmstream) goto fail;

    start_offset = 0x18;
    vgmstream->channels = channel_count;
    vgmstream->sample_rate = read_32bitLE(0x0C,streamFile);
    vgmstream->coding_type = coding_MAXIS_MT10;
    vgmstream->num_samples = read_32bitLE(0x04,streamFile)/2/channel_count;

    vgmstream->layout_type = layout_none;
    vgmstream->meta_type = meta_MAXIS_XA;

    /* open streams */
    if (!vgmstream_open_stream(vgmstream,streamFile,start_offset))
        goto fail;

    /* fix channel offsets as needed by the codec (could be simplified) */
    for (i = 0; i < channel_count; i++) {
        vgmstream->ch[i].channel_start_offset = start_offset+i;
        vgmstream->ch[i].offset = 0;
    }

    return vgmstream;

fail:
    close_vgmstream(vgmstream);
    return NULL;
}