Nicklas' tech notes: June 2016

Godbolt online compiler

Mapcrafter

Home page: https://mapcrafter.org/index

Config:

output_dir = output

[world:s6snapshot]
input_dir = /home/ne/Minecraft/SERVER/s6snapshot/world

[map:map_s6snapshot]
name = 20160605
world = s6snapshot

The $4 mobile phone

From Strategy Analytics: https://www.strategyanalytics.com/strategy-analytics/blogs/devices/handset-country-share/handset-country-share/2016/06/29/us$4-smartphone-closer-to-reality#.V3WWIu3SphE

XDA-developers: http://www.xda-developers.com/freedom-251-the-4-smartphone-is-on-course-to-reach-consumers/

Scott Galloway on the 4 big companies

Gang of Four: Apple / Amazon / Facebook / Google (Scott Galloway, Founder of L2) | DLD16: https://www.youtube.com/watch?v=jfjg0kGQFBY

L2inc YouTube channel: https://www.youtube.com/c/l2inc

Display doesn't power on/off properly

Configuration: Ubuntu 16.04, xfce, two HP EliteDisplay E232, displayport, Nvidia GTX960.

Problems:

Displays don't enter sleep mode.
If displays are turned off, they are lost by the Ubuntu system and the computer will need to be rebooted.

Some pages:

The bug fix mentioned partly solves the issue with getting the displays working again after being powered off.

Add simple service Dragonboard

Update init.rc:

commit f2bb12973675d86526cdf5e815b9314b8d51a3e0
Author: Nicklas Ekstrand
Date:   Tue Jun 7 22:04:49 2016 +0200

    Added serivce nicklas

    Change-Id: I4eff38d220b5d8bcab7f59ebcede7e7ffe90b02c

diff --git a/rootdir/init.rc b/rootdir/init.rc
index ea2b009..172d02e 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -639,3 +639,9 @@ service pre-recovery /system/bin/uncrypt
     class main
     disabled
     oneshot
+
+service nicklas /system/bin/nicklas
+    class main
+    enabled
+    oneshot

nicklas.c:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

void mywrite (int x)
{
    FILE *fp = fopen("/sys/class/leds/led3/brightness","w");
    if (fp != NULL)
    {
        fprintf(fp, "%d",x);
        fclose(fp);
    }
}

int main (int argc, char* argv[])
{
    printf ("Nicklas!\n");

    while (1){
        mywrite(255);
        usleep(100000);
        mywrite(0);
        usleep(100000);
    }
    return 0;
}

Compile:

~/android/my64/bin/aarch64-linux-android-gcc -Wall -pedantic nicklas.c -o nicklas -static

Building Android for Dragonboard 410c

Qualcomm developer site: developer.qualcomm.com
There have been some issue when building the SW on the LA.BR.1.2.4 release on Ubuntu 16.04. Build problem:

commit 53cd4ef6c81344e1695eff186722662684d3b58b
Author: Nicklas Ekstrand
Date: Thu Jun 30 23:15:10 2016 +0200

Nicklas

Change-Id: Ia7c7279e0963df37fa1a05fa4fc0cf1ebc3a2dc1

diff --git a/core/clang/HOST_x86_common.mk b/core/clang/HOST_x86_common.mk
index 0241cb6..ba3a583 100644
--- a/core/clang/HOST_x86_common.mk
+++ b/core/clang/HOST_x86_common.mk
@@ -7,8 +7,9 @@ endif
ifeq ($(HOST_OS),linux)
CLANG_CONFIG_x86_LINUX_HOST_EXTRA_ASFLAGS := \
--gcc-toolchain=$($(clang_2nd_arch_prefix)HOST_TOOLCHAIN_FOR_CLANG) \
- --sysroot=$($(clang_2nd_arch_prefix)HOST_TOOLCHAIN_FOR_CLANG)/sysroot \
- -no-integrated-as
+ -no-integrated-as \
+ --sysroot $($(clang_2nd_arch_prefix)HOST_TOOLCHAIN_FOR_CLANG)/sysroot \
+ -B$($(clang_2nd_arch_prefix)HOST_TOOLCHAIN_FOR_CLANG)/x86_64-linux/bin

CLANG_CONFIG_x86_LINUX_HOST_EXTRA_CFLAGS := \
--gcc-toolchain=$($(clang_2nd_arch_prefix)HOST_TOOLCHAIN_FOR_CLANG) \

Java build error:

make update-api

Flashing (reference):

adb reboot bootloader
sudo fastboot devices

sudo fastboot flash boot boot.img
sudo fastboot flash system system.img
sudo fastboot flash userdata userdata.img
sudo fastboot flash recovery recovery.img
sudo fastboot flash persist persist.img
sudo fastboot flash cache cache.img

sudo fastboot reboot

Android NDK standalone toolchain

Download Android NDK: developer.android.com
Android reference: developer.android.com

Example:

./android-ndk-r11c/build/tools/make-standalone-toolchain.sh --arch=arm64 --platform=android-21 --install-dir=my64 --toolchain=aarch64-linux-android-4.9

FFmpeg

Documentation: ffmpeg.org

Concatenate: ffmpeg.org

Example:

ffmpeg -f concat -i mylist.txt -c copy out.mp4

mylist.txt:

file 'GOPR3733.MP4'
file 'GP013733.MP4'
file 'GP023733.MP4'
file 'GP033733.MP4'
file 'GP043733.MP4'
file 'GP053733.MP4'
file 'GP063733.MP4'
file 'GP073733.MP4'

Rate limit: ffmpeg.org

Example:

ffmpeg -i out.mp4 -b:v 4000k -bufsize 4000k -strict -2 out2.mp4

Thursday, June 30, 2016