Method copyFile

switch/source/io.cpp:246–341

}

Result io::copyFile(const std::string& srcPath, const std::string& dstPath, ProgressSink& sink, u64 commitWriteLimit)
{
    FILE* src = fopen(srcPath.c_str(), "rb");
    if (src == NULL) {
        Logging::error("Failed to open source file {} during copy with errno {}.", srcPath, errno);
        return RES_COPY_FAILED;
    }
    FILE* dst = fopen(dstPath.c_str(), "wb");
    if (dst == NULL) {
        Logging::error("Failed to open destination file {} during copy with errno {}.", dstPath, errno);
        fclose(src);
        return RES_COPY_FAILED;
    }

    fseek(src, 0, SEEK_END);
    u64 sz = ftell(src);
    rewind(src);

    u8* buf    = new u8[BUFFER_SIZE];
    u64 offset = 0;
    Result res = 0;

    size_t slashpos = srcPath.rfind("/");
    sink.startFile(srcPath.substr(slashpos + 1, srcPath.length() - slashpos - 1), sz);

    // The save journal only holds `commitWriteLimit` bytes of uncommitted writes:
    // a single file bigger than that must be committed partway through, or the
    // commit at the end would overflow the journal and fail (#443, #297).
    const bool toSaveDevice = dstPath.rfind("save:/", 0) == 0;
    u64 journalPending      = 0;

    while (offset < sz) {
        if (sink.cancelled()) {
            break;
        }

        size_t count = fread((char*)buf, 1, BUFFER_SIZE, src);
        if (count == 0) {
            Logging::error("fread returned 0 for file {} at offset {}/{} with errno {}. Aborting copy.", srcPath, offset, sz, errno);
            res = RES_COPY_FAILED;
            break;
        }

        // commit *before* the write that would cross the limit, while the
        // journal still has room for it
        if (toSaveDevice && commitWriteLimit > 0 && journalPending + count > commitWriteLimit && journalPending > 0) {
            if (fclose(dst) != 0) {
                Logging::error("fclose before mid-file commit failed for {} with errno {}. Aborting copy.", dstPath, errno);
                dst = NULL;
                res = RES_COPY_FAILED;
                break;
            }
            res = fsdevCommitDevice("save");
            if (R_FAILED(res)) {
                Logging::error("Mid-file commit of {} at offset {}/{} failed with result 0x{:08X}. Aborting copy.", dstPath, offset, sz, (u32)res);
                dst = NULL;
                break;
            }