Function AllocAndCopyFilePath

extern/nfd/nfd_portal.cpp:1007–1027

If fileUri starts with "file://", strips that prefix and URI-decodes the remaining part to a new buffer, and make outPath point to it, and returns NFD_OKAY. Otherwise, does not modify outPath and returns NFD_ERROR (with the correct error set)

// buffer, and make outPath point to it, and returns NFD_OKAY. Otherwise, does not modify outPath
// and returns NFD_ERROR (with the correct error set)
nfdresult_t AllocAndCopyFilePath(const char* fileUri, char*& outPath) {
    const char* prefix_begin = FILE_URI_PREFIX;
    const char* const prefix_end = FILE_URI_PREFIX + FILE_URI_PREFIX_LEN;
    for (; prefix_begin != prefix_end; ++prefix_begin, ++fileUri) {
        if (*prefix_begin != *fileUri) {
            NFDi_SetError("D-Bus freedesktop portal returned a URI that is not a file URI.");
            return NFD_ERROR;
        }
    }
    size_t decoded_len;
    const char* file_uri_end;
    if (!TryUriDecodeLen(fileUri, decoded_len, file_uri_end)) {
        NFDi_SetError("D-Bus freedesktop portal returned a malformed URI.");
        return NFD_ERROR;
    }
    char* const path_without_prefix = NFDi_Malloc<char>(decoded_len + 1);
    char* const out_end = UriDecodeUnchecked(fileUri, file_uri_end, path_without_prefix);
    *out_end = '\0';
    outPath = path_without_prefix;
    return NFD_OKAY;
}

#ifdef NFD_APPEND_EXTENSION
bool TryGetValidExtension(const char* extn,