Function adfReadFile

dep/adflib/src/adf_file.c:369–407

* adfReadFile * */

 *
 */
int32_t adfReadFile(struct File* file, int32_t n, uint8_t *buffer)
{
    int32_t bytesRead;
    uint8_t *dataPtr, *bufPtr;
	int blockSize, size;

    if (n==0) return(n);
    blockSize = file->volume->datablockSize;
/*puts("adfReadFile");*/
    if (file->pos+n > file->fileHdr->byteSize)
        n = file->fileHdr->byteSize - file->pos;

    if (isOFS(file->volume->dosType))
        dataPtr = (uint8_t*)(file->currentData)+24;
    else
        dataPtr = file->currentData;

    if (file->pos==0 || file->posInDataBlk==blockSize) {
        adfReadNextFileBlock(file);
        file->posInDataBlk = 0;
    }

    bytesRead = 0; bufPtr = buffer;
    size = 0;
    while ( bytesRead < n ) {
        size = min(n-bytesRead, blockSize-file->posInDataBlk);
        memcpy(bufPtr, dataPtr+file->posInDataBlk, size);
        bufPtr += size;
        file->pos += size;
        bytesRead += size;
        file->posInDataBlk += size;
        if (file->posInDataBlk==blockSize && bytesRead<n) {
            adfReadNextFileBlock(file);
            file->posInDataBlk = 0;
        }
    }
    file->eof = (file->pos==file->fileHdr->byteSize);
    return( bytesRead );
}


/*