Merge "adb: print emulator console output" am: 3e3797a9

    // preventing the emulator from reading the command that adb has sent.

    // https://code.google.com/p/android/issues/detail?id=21021

    int result;

    std::string emulator_output;

    do {

        char buf[BUFSIZ];

        result = adb_read(fd, buf, sizeof(buf));

        // appended above, and that causes the emulator to close the socket

        // which should cause zero bytes (orderly/graceful shutdown) to be

        // returned.

        if (result > 0) emulator_output.append(buf, result);

    } while (result > 0);

    // Note: the following messages are expected to be quite stable from emulator.

    //

    // Emulator console will send the following message upon connection:

    //

    // Android Console: Authentication required

    // Android Console: type 'auth <auth_token>' to authenticate

    // Android Console: you can find your <auth_token> in

    // '/<path-to-home>/.emulator_console_auth_token'

    // OK\r\n

    //

    // and the following after authentication:

    // Android Console: type 'help' for a list of commands

    // OK\r\n

    //

    // So try search and skip first two "OK\r\n", print the rest.

    //

    const std::string delims = "OK\r\n";

    size_t found = 0;

    for (int i = 0; i < 2; ++i) {

        const size_t result = emulator_output.find(delims, found);

        if (result == std::string::npos) {

            break;

        } else {

            found = result + delims.size();

        }

    }

    printf("%s", emulator_output.c_str() + found);

    adb_close(fd);

    return 0;