Initial commit

.devcontainer/devcontainer.json

@@ -0,0 +1,12 @@
+{
+    "name": "csel",
+    "dockerComposeFile": "docker-compose.yml",
+    "service": "toolchain",
+    "workspaceFolder": "/workspace",
+    "shutdownAction": "stopCompose",
+
+    "settings": {},
+    "extensions": [
+        "ms-vscode.cpptools"
+    ]
+}

.devcontainer/docker-compose.yml

@@ -0,0 +1,44 @@
+services:
+  toolchain:
+    image: csel/toolchain
+    build:
+      context: toolchain
+      dockerfile: Dockerfile
+    cap_add:
+    - SYS_PTRACE
+    security_opt:
+    - seccomp:unconfined
+    volumes:
+      - ..:/workspace:cached
+      - buildroot:/buildroot
+      - rootfs:/rootfs
+      - home:/root-home
+      
+    # Overrides default command so things don't shut down after the process ends.
+    command: /bin/sh -c "while sleep 1000; do :; done"  
+
+  samba:
+    image: dperson/samba
+    environment:
+      USERID: 0
+      GROUPID: 0
+    command: >-
+      -S 
+      -u "root;toor"
+      -s "buildroot;/buildroot;no;no"
+      -s "rootfs;/rootfs;no;no"
+      -s "workspace;/workspace;no;no"
+      -s "home;/root-home;no;no"
+    ports:
+      - "139:139"
+      - "1445:445"
+    volumes:
+      - ..:/workspace:cached
+      - buildroot:/buildroot
+      - rootfs:/rootfs
+      - home:/root-home
+
+volumes:
+  buildroot: {}
+  rootfs: {}
+  home: {}

.devcontainer/main.code-workspace

@@ -0,0 +1,32 @@
+{
+	"folders": [
+		{
+			"path": ".."
+		},
+		{
+			"path": "../src/backtrace"
+		},
+		{
+			"path": "../src/core_dumps"
+		},
+		{
+			"path": "../src/daemon"
+		},
+		{
+			"path": "../src/fibonacci"
+		},
+		{
+			"path": "../src/memory_leaks"
+		},
+		{
+			"path": "../src/process"
+		},
+		{
+			"path": "../src/system_calls"
+		},
+		{
+			"path": "../src/tracing"
+		}
+	],
+	"settings": {}
+}

.devcontainer/toolchain/Dockerfile

@@ -0,0 +1,29 @@
+# [Choice] Debian / Ubuntu version (use Debian 11, Ubuntu 18.04/21.04 on local arm64/Apple Silicon): debian-11, debian-10, ubuntu-21.04, ubuntu-20.04, ubuntu-18.04
+ARG VARIANT=ubuntu-21.04
+FROM mcr.microsoft.com/vscode/devcontainers/cpp:0-${VARIANT}
+
+RUN apt-get update && \
+    export DEBIAN_FRONTEND=noninteractive && \
+    apt-get -y install --no-install-recommends \
+    autoconf \
+    automake \
+    bc \
+    bison \
+    cpio \
+    device-tree-compiler \
+    file \
+    flex \
+    libfl-dev \
+    libglib2.0-dev \
+    libssl-dev \
+    libubootenv-tool \
+    libyaml-dev \
+    mercurial \
+    python3-dev \
+    rsync \
+    swig \
+    u-boot-tools \
+    wget
+
+COPY scripts/* /usr/local/bin/
+RUN chmod +x /usr/local/bin/*

.devcontainer/toolchain/scripts/delete-buildroot.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+find /buildroot/ -maxdepth 1 -mindepth 1 -exec rm -rf -- {} +

.devcontainer/toolchain/scripts/delete-rootfs.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+find /rootfs/ -maxdepth 1 -mindepth 1 -exec rm -rf -- {} +

.devcontainer/toolchain/scripts/extract-rootfs.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+tar xf /buildroot/output/images/rootfs.tar -C /rootfs/

.devcontainer/toolchain/scripts/get-buildroot.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+git clone git://git.buildroot.net/buildroot /buildroot
+
+rsync -a /workspace/config/board/ /buildroot/board/
+rsync -a /workspace/config/configs/ /buildroot/configs/
+
+cd /buildroot
+git checkout -b csel 2021.11.1
+
+make csel_defconfig

.devcontainer/toolchain/scripts/sync-images.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+rsync -rlt --progress --delete /buildroot/output/images/ /workspace/buildroot-images

.gitignore

@@ -0,0 +1,4 @@
+images
+buildroot-images
+src/*/app
+.obj

.vscode/extensions.json

@@ -0,0 +1,12 @@
+{
+    "recommendations": [
+        "ms-vscode-remote.remote-containers",
+        "ms-vscode-remote.remote-ssh",
+        "ms-vscode-remote.remote-ssh-edit",
+        "ms-vscode-remote.remote-wsl",
+        "ms-vscode.cpptools",
+        "ms-vscode.cpptools-extension-pack",
+        "dan-c-underwood.arm",
+        "editorconfig.editorconfig"
+    ]
+  }

README.md

@@ -0,0 +1,39 @@
+# Workspace for CSEL
+
+> :warning: **Open this project in a Docker Container**
+
+## Cheat Sheet for developers
+
+Configure with the default settings:
+
+```
+cd /buildroot
+make csel_defconfig
+```
+
+Make changes if you want:
+
+```
+make menuconfig
+```
+
+Build:
+
+```
+make
+```
+
+If you change the configuration and want to keep it in the workspace, do the following:
+
+```
+make savedefconfig
+cp /buildroot/configs/csel_defconfig /workspace/config/configs/
+```
+
+When the build is done, copy the images from buildroot to the workspace
+
+```
+sync-images.sh
+```
+
+You can now "burn" the Compact Flash using [BalenaEtcher](https://www.balena.io/etcher/)

config/board/friendlyarm/nanopi-neo-plus2/boot.cmd

@@ -0,0 +1,6 @@
+setenv bootargs console=ttyS0,115200 earlyprintk root=/dev/mmcblk2p2 rootwait
+
+fatload mmc 0 $kernel_addr_r Image
+fatload mmc 0 $fdt_addr_r nanopi-neo-plus2.dtb
+
+booti $kernel_addr_r - $fdt_addr_r

config/board/friendlyarm/nanopi-neo-plus2/genimage.cfg

@@ -0,0 +1,41 @@
+image boot.vfat {
+	vfat {
+		label = "boot"
+		files = {
+			"Image",
+			"nanopi-neo-plus2.dtb",
+			"boot.scr"
+		}
+	}
+
+	size = 64M
+}
+
+image sdcard.img {
+	hdimage {
+	}
+
+	partition spl {
+		in-partition-table = "no"
+		image = "sunxi-spl.bin"
+		offset = 8K
+	}
+
+	partition u-boot {
+		in-partition-table = "no"
+		image = "u-boot.itb"
+		offset = 40K
+		size = 1M # 1MB - 40KB
+	}
+
+	partition boot {
+		partition-type = 0xC
+		bootable = "true"
+		image = "boot.vfat"
+	}
+
+	partition rootfs {
+		partition-type = 0x83
+		image = "rootfs.ext4"
+	}
+}

config/board/friendlyarm/nanopi-neo-plus2/linux-extras.config

@@ -0,0 +1,27 @@
+# wireless core
+CONFIG_WIRELESS=y
+CONFIG_CFG80211=y
+CONFIG_MAC80211=y
+CONFIG_CFG80211_WEXT=y
+
+# wireless drivers
+CONFIG_WLAN=y
+CONFIG_WLAN_VENDOR_BROADCOM=y
+CONFIG_BRCMFMAC=m
+
+# enable GPIO sysfs
+CONFIG_EMBEDDED=y
+CONFIG_GPIO_SYSFS=y
+
+# enable CIFS/SAMBA
+CONFIG_CIFS=y
+CONFIG_CIFS_XATTR=y
+CONFIG_CIFS_POSIX=y
+CONFIG_CIFS_ROOT=y
+
+#network interface device drivers (to mount rootfs)
+CONFIG_NET_VENDOR_STMICRO=y
+CONFIG_STMMAC_ETH=y
+CONFIG_STMMAC_PLATFORM=y
+CONFIG_DWMAC_SUNXI=y
+CONFIG_DWMAC_SUN8I=y

config/board/friendlyarm/nanopi-neo-plus2/nanopi-neo-plus2.dts

@@ -0,0 +1,7 @@
+/dts-v1/;
+
+#include "allwinner/sun50i-h5-nanopi-neo-plus2.dts"
+
+/ {
+        /delete-node/ leds;
+};

config/board/friendlyarm/nanopi-neo-plus2/rootfs_overlay/etc/network/interfaces

@@ -0,0 +1,10 @@
+# interface file auto-generated by buildroot for CSEL
+
+auto lo
+iface lo inet loopback
+
+auto eth0
+iface eth0 inet static
+    address 192.168.0.14
+    netmask 255.255.255.0
+    gateway 192.168.0.4

config/board/friendlyarm/nanopi-neo-plus2/rootfs_overlay/etc/ssh/sshd_config

@@ -0,0 +1,117 @@
+# sshd_config for csel
+
+# This is the sshd server system-wide configuration file.  See
+# sshd_config(5) for more information.
+
+# This sshd was compiled with PATH=/bin:/sbin:/usr/bin:/usr/sbin
+
+# The strategy used for options in the default sshd_config shipped with
+# OpenSSH is to specify options with their default value where
+# possible, but leave them commented.  Uncommented options override the
+# default value.
+
+#Port 22
+#AddressFamily any
+#ListenAddress 0.0.0.0
+#ListenAddress ::
+
+#HostKey /etc/ssh/ssh_host_rsa_key
+#HostKey /etc/ssh/ssh_host_ecdsa_key
+#HostKey /etc/ssh/ssh_host_ed25519_key
+
+# Ciphers and keying
+#RekeyLimit default none
+
+# Logging
+#SyslogFacility AUTH
+#LogLevel INFO
+
+# Authentication:
+
+#LoginGraceTime 2m
+#PermitRootLogin prohibit-password
+PermitRootLogin yes
+#StrictModes yes
+#MaxAuthTries 6
+#MaxSessions 10
+
+#PubkeyAuthentication yes
+
+# The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
+# but this is overridden so installations will only check .ssh/authorized_keys
+AuthorizedKeysFile	.ssh/authorized_keys
+
+#AuthorizedPrincipalsFile none
+
+#AuthorizedKeysCommand none
+#AuthorizedKeysCommandUser nobody
+
+# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
+#HostbasedAuthentication no
+# Change to yes if you don't trust ~/.ssh/known_hosts for
+# HostbasedAuthentication
+#IgnoreUserKnownHosts no
+# Don't read the user's ~/.rhosts and ~/.shosts files
+#IgnoreRhosts yes
+
+# To disable tunneled clear text passwords, change to no here!
+#PasswordAuthentication yes
+PermitEmptyPasswords yes
+
+# Change to no to disable s/key passwords
+#KbdInteractiveAuthentication yes
+
+# Kerberos options
+#KerberosAuthentication no
+#KerberosOrLocalPasswd yes
+#KerberosTicketCleanup yes
+#KerberosGetAFSToken no
+
+# GSSAPI options
+#GSSAPIAuthentication no
+#GSSAPICleanupCredentials yes
+
+# Set this to 'yes' to enable PAM authentication, account processing,
+# and session processing. If this is enabled, PAM authentication will
+# be allowed through the KbdInteractiveAuthentication and
+# PasswordAuthentication.  Depending on your PAM configuration,
+# PAM authentication via KbdInteractiveAuthentication may bypass
+# the setting of "PermitRootLogin without-password".
+# If you just want the PAM account and session checks to run without
+# PAM authentication, then enable this but set PasswordAuthentication
+# and KbdInteractiveAuthentication to 'no'.
+#UsePAM no
+
+#AllowAgentForwarding yes
+#AllowTcpForwarding yes
+#GatewayPorts no
+#X11Forwarding no
+#X11DisplayOffset 10
+#X11UseLocalhost yes
+#PermitTTY yes
+#PrintMotd yes
+#PrintLastLog yes
+#TCPKeepAlive yes
+#PermitUserEnvironment no
+#Compression delayed
+#ClientAliveInterval 0
+#ClientAliveCountMax 3
+#UseDNS no
+#PidFile /var/run/sshd.pid
+#MaxStartups 10:30:100
+#PermitTunnel no
+#ChrootDirectory none
+#VersionAddendum none
+
+# no default banner path
+#Banner none
+
+# override default of no subsystems
+Subsystem	sftp	/usr/libexec/sftp-server
+
+# Example of overriding settings on a per-user basis
+#Match User anoncvs
+#	X11Forwarding no
+#	AllowTcpForwarding no
+#	PermitTTY no
+#	ForceCommand cvs server

config/board/friendlyarm/nanopi-neo-plus2/uboot-extras.config

@@ -0,0 +1,2 @@
+# Save env to SD Card
+CONFIG_ENV_FAT_DEVICE_AND_PART="0:auto"

config/configs/csel_defconfig

@@ -0,0 +1,109 @@
+BR2_aarch64=y
+BR2_ARM_FPU_VFPV4=y
+BR2_SSP_NONE=y
+BR2_TOOLCHAIN_BUILDROOT_GLIBC=y
+BR2_PACKAGE_GLIBC_UTILS=y
+BR2_TOOLCHAIN_BUILDROOT_CXX=y
+BR2_PACKAGE_HOST_GDB=y
+BR2_PACKAGE_HOST_GDB_TUI=y
+BR2_PACKAGE_HOST_GDB_PYTHON3=y
+BR2_TARGET_GENERIC_HOSTNAME="csel"
+BR2_TARGET_GENERIC_ISSUE="Welcome to FriendlyARM Nanopi NEO Plus2"
+BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_MDEV=y
+BR2_ROOTFS_OVERLAY="board/friendlyarm/nanopi-neo-plus2/rootfs_overlay"
+BR2_ROOTFS_POST_BUILD_SCRIPT="board/friendlyarm/nanopi-neo-plus2/post-build.sh"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/friendlyarm/nanopi-neo-plus2/genimage.cfg"
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.15.21"
+BR2_LINUX_KERNEL_USE_ARCH_DEFAULT_CONFIG=y
+BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="board/friendlyarm/nanopi-neo-plus2/linux-extras.config"
+BR2_LINUX_KERNEL_DTS_SUPPORT=y
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="allwinner/sun50i-h5-nanopi-neo-plus2"
+BR2_LINUX_KERNEL_CUSTOM_DTS_PATH="board/friendlyarm/nanopi-neo-plus2/nanopi-neo-plus2.dts"
+BR2_LINUX_KERNEL_DTB_OVERLAY_SUPPORT=y
+BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
+BR2_PACKAGE_LINUX_TOOLS_PERF=y
+BR2_PACKAGE_LINUX_TOOLS_PERF_TUI=y
+BR2_PACKAGE_BUSYBOX_SHOW_OTHERS=y
+BR2_PACKAGE_GDB=y
+BR2_PACKAGE_GDB_SERVER=y
+BR2_PACKAGE_GDB_DEBUGGER=y
+BR2_PACKAGE_GDB_TUI=y
+BR2_PACKAGE_LSOF=y
+BR2_PACKAGE_LTRACE=y
+BR2_PACKAGE_STRACE=y
+BR2_PACKAGE_VALGRIND=y
+BR2_PACKAGE_DOSFSTOOLS=y
+BR2_PACKAGE_DOSFSTOOLS_FATLABEL=y
+BR2_PACKAGE_DOSFSTOOLS_FSCK_FAT=y
+BR2_PACKAGE_DOSFSTOOLS_MKFS_FAT=y
+BR2_PACKAGE_E2FSPROGS_RESIZE2FS=y
+BR2_PACKAGE_E2TOOLS=y
+BR2_PACKAGE_SSHFS=y
+BR2_PACKAGE_LINUX_FIRMWARE=y
+BR2_PACKAGE_LINUX_FIRMWARE_BRCM_BCM43XXX=y
+BR2_PACKAGE_I2C_TOOLS=y
+BR2_PACKAGE_UBOOT_TOOLS=y
+BR2_PACKAGE_UBOOT_TOOLS_FIT_SUPPORT=y
+BR2_PACKAGE_UBOOT_TOOLS_FIT_SIGNATURE_SUPPORT=y
+BR2_PACKAGE_UBOOT_TOOLS_FIT_CHECK_SIGN=y
+BR2_PACKAGE_MYSQL=y
+BR2_PACKAGE_MARIADB=y
+BR2_PACKAGE_SQLITE=y
+BR2_PACKAGE_SQLITE_STAT4=y
+BR2_PACKAGE_SQLITE_ENABLE_COLUMN_METADATA=y
+BR2_PACKAGE_SQLITE_ENABLE_FTS3=y
+BR2_PACKAGE_SQLITE_ENABLE_JSON1=y
+BR2_PACKAGE_SQLITE_ENABLE_UNLOCK_NOTIFY=y
+BR2_PACKAGE_SQLITE_SECURE_DELETE=y
+BR2_PACKAGE_EXPAT=y
+BR2_PACKAGE_JSON_C=y
+BR2_PACKAGE_JSONCPP=y
+BR2_PACKAGE_LIBYAML=y
+BR2_PACKAGE_YAML_CPP=y
+BR2_PACKAGE_IFUPDOWN=y
+BR2_PACKAGE_IPTABLES=y
+BR2_PACKAGE_IPTABLES_BPF_NFSYNPROXY=y
+BR2_PACKAGE_IPTABLES_NFTABLES=y
+BR2_PACKAGE_IPUTILS=y
+BR2_PACKAGE_IW=y
+BR2_PACKAGE_WIRELESS_TOOLS=y
+BR2_PACKAGE_WIRELESS_TOOLS_LIB=y
+BR2_PACKAGE_WPA_SUPPLICANT=y
+BR2_PACKAGE_WPA_SUPPLICANT_CLI=y
+BR2_PACKAGE_FILE=y
+BR2_PACKAGE_COREUTILS=y
+BR2_PACKAGE_HTOP=y
+BR2_PACKAGE_PROCPS_NG=y
+BR2_TARGET_ROOTFS_EXT2=y
+BR2_TARGET_ROOTFS_EXT2_4=y
+BR2_TARGET_ROOTFS_EXT2_SIZE="2G"
+BR2_TARGET_ARM_TRUSTED_FIRMWARE=y
+BR2_TARGET_ARM_TRUSTED_FIRMWARE_CUSTOM_GIT=y
+BR2_TARGET_ARM_TRUSTED_FIRMWARE_CUSTOM_REPO_URL="https://github.com/apritzel/arm-trusted-firmware.git"
+BR2_TARGET_ARM_TRUSTED_FIRMWARE_CUSTOM_REPO_VERSION="aa75c8da415158a94b82a430b2b40000778e851f"
+BR2_TARGET_ARM_TRUSTED_FIRMWARE_PLATFORM="sun50iw1p1"
+BR2_TARGET_UBOOT=y
+BR2_TARGET_UBOOT_BUILD_SYSTEM_KCONFIG=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2020.07"
+BR2_TARGET_UBOOT_BOARD_DEFCONFIG="nanopi_neo_plus2"
+BR2_TARGET_UBOOT_CONFIG_FRAGMENT_FILES="board/friendlyarm/nanopi-neo-plus2/uboot-extras.config"
+BR2_TARGET_UBOOT_NEEDS_DTC=y
+BR2_TARGET_UBOOT_NEEDS_PYTHON3=y
+BR2_TARGET_UBOOT_NEEDS_PYLIBFDT=y
+BR2_TARGET_UBOOT_NEEDS_ATF_BL31=y
+BR2_TARGET_UBOOT_FORMAT_CUSTOM=y
+BR2_TARGET_UBOOT_FORMAT_CUSTOM_NAME="u-boot.itb"
+BR2_TARGET_UBOOT_SPL=y
+BR2_TARGET_UBOOT_SPL_NAME="spl/sunxi-spl.bin"
+BR2_PACKAGE_HOST_DOSFSTOOLS=y
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_PACKAGE_HOST_MTOOLS=y
+BR2_PACKAGE_HOST_UBOOT_TOOLS=y
+BR2_PACKAGE_HOST_UBOOT_TOOLS_FIT_SUPPORT=y
+BR2_PACKAGE_HOST_UBOOT_TOOLS_FIT_SIGNATURE_SUPPORT=y
+BR2_PACKAGE_HOST_UBOOT_TOOLS_BOOT_SCRIPT=y
+BR2_PACKAGE_HOST_UBOOT_TOOLS_BOOT_SCRIPT_SOURCE="board/friendlyarm/nanopi-neo-plus2/boot.cmd"

src/Makefile

@@ -0,0 +1,4 @@
+DIRS=$(filter-out Makefile appl.mk dot-vscode, $(wildcard *))
+all clean clean_all:
+	for dir in $(DIRS); do $(MAKE) $@ -C $$dir; done
+

src/appl.mk

@@ -0,0 +1,45 @@
+CFLAGS=-Wall -Wextra -g -c -O0 -MD -std=gnu11
+CFLAGS+=$(EXTRA_CFLAGS)
+
+TOOLCHAIN_PATH=/buildroot/output/host/usr/bin/
+TOOLCHAIN=$(TOOLCHAIN_PATH)aarch64-linux-
+CFLAGS+=-mcpu=cortex-a53 -funwind-tables
+##CFLAGS+=-O2 -fno-omit-frame-pointer
+OBJDIR=.obj/nano
+EXEC=$(EXE)
+
+ifeq ($(target),host)
+EXEC=$(EXE)_h
+endif
+
+CC=$(TOOLCHAIN)gcc
+LD=$(TOOLCHAIN)gcc
+AR=$(TOOLCHAIN)ar
+STRIP=$(TOOLCHAIN)strip
+
+OBJDIR=.obj/$(target)
+OBJS= $(addprefix $(OBJDIR)/, $(SRCS:.c=.o))
+
+$(OBJDIR)/%o: %c
+	$(CC) $(CFLAGS) $< -o $@
+
+all: $(OBJDIR)/ $(EXEC)
+
+$(EXEC): $(OBJS) $(LINKER_SCRIPT)
+	$(LD) $(OBJS) $(LDFLAGS) -o $@
+
+$(OBJDIR)/:
+	mkdir -p $(OBJDIR)
+
+clean:
+	rm -Rf $(OBJDIR) $(EXEC) $(EXEC)_s *~
+
+clean_all: clean
+	rm -Rf .obj $(EXE) $(EXE)_s $(EXE)_a $(EXE)_a_s $(EXE)_h $(EXE)_h_s
+
+-include $(OBJS:.o=.d)
+
+.PHONY: all clean clean_all
+
+
+

src/backtrace/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/backtrace/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/backtrace/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/backtrace/main.c

@@ -0,0 +1,63 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	Backtracing demo program.
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <execinfo.h>
+#include <unistd.h>
+#include <signal.h>
+
+#define SIZE 1000
+
+void signal_handler(int __attribute__((unused)) sig)
+{
+	void* buffer[SIZE];
+	int nptrs = backtrace(buffer, SIZE);
+	printf("backtrace() returned %d addresses\n", nptrs);
+	backtrace_symbols_fd (buffer, nptrs, STDOUT_FILENO);
+	exit(EXIT_FAILURE);
+}
+
+void access_data() 
+{
+	int* p=0;
+	*p=10;
+}
+
+void call (int n)
+{
+	if (n>0) call (n-1);
+	access_data();
+}
+
+
+int main ()
+{
+	signal(SIGSEGV, signal_handler); // Invalid memory segment access 
+
+	call(10);
+
+	return 0;
+}

src/core_dumps/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/core_dumps/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/core_dumps/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/core_dumps/core_dumps.c

@@ -0,0 +1,45 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	Core dump demo program.
+ * 		Before to call this demo program don't forget set
+ *              $ ulimit -c 10000
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+void access_data() 
+{
+	int* p=0;
+	*p=10;
+}
+
+void call (int n)
+{
+	if (n>0) call (n-1);
+	access_data();
+}
+
+
+int main ()
+{
+	call(10);
+	return 0;
+}

src/daemon/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/daemon/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/daemon/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/daemon/S60appl

@@ -0,0 +1,24 @@
+#!/bin/sh
+#
+# Daemon application
+#
+case "$1" in
+  start)
+  	/usr/local/app_a
+	;;
+  stop)
+  	killall app_a
+	;;
+  restart|reload)
+  	killall app_a
+	/usr/local/app_a
+	;;
+  *)
+	echo $"Usage: $0 {start|stop|restart}"
+	exit 1
+esac
+
+echo "Daemon application launched"
+
+exit $?
+

src/daemon/daemon.c

@@ -0,0 +1,152 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	This module implements a simple daemon to be launched
+ *		from a /etc/init.d/S??_* script
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+#define _XOPEN_SOURCE 600
+#define _DEFAULT_SOURCE
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <grp.h>
+#include <pwd.h>
+#include <signal.h>
+#include <syslog.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#define UNUSED(x) (void)(x)
+
+static int signal_catched = 0; 
+
+static void catch_signal (int signal)
+{
+	syslog (LOG_INFO, "signal=%d catched\n", signal);
+	signal_catched++;
+}
+
+static void fork_process()
+{
+	pid_t pid = fork();
+	switch (pid) {
+	case  0: break; 	// child process has been created
+	case -1: syslog (LOG_ERR, "ERROR while forking"); exit (1); break;	
+	default: exit(0);  	// exit parent process with success
+	}
+}
+
+int main(int argc, char* argv[])
+{
+	UNUSED(argc); UNUSED(argv);
+
+	// 1. fork off the parent process
+	fork_process();
+
+	// 2. create new session
+	if (setsid() == -1) {
+		syslog (LOG_ERR, "ERROR while creating new session"); 
+		exit (1);
+	}
+
+	// 3. fork again to get rid of session leading process 
+	fork_process();
+
+	// 4. capture all required signals
+	struct sigaction act = {.sa_handler = catch_signal,};
+	sigaction (SIGHUP,  &act, NULL);  //  1 - hangup
+	sigaction (SIGINT,  &act, NULL);  //  2 - terminal interrupt
+	sigaction (SIGQUIT, &act, NULL);  //  3 - terminal quit
+	sigaction (SIGABRT, &act, NULL);  //  6 - abort
+	sigaction (SIGTERM, &act, NULL);  // 15 - termination
+	sigaction (SIGTSTP, &act, NULL);  // 19 - terminal stop signal
+
+	// 5. update file mode creation mask
+	umask(0027);
+
+	// 6. change working directory to appropriate place
+	if (chdir ("/") == -1) {
+		syslog (LOG_ERR, "ERROR while changing to working directory"); 
+		exit (1);
+	}
+
+	// 7. close all open file descriptors
+	for (int fd = sysconf(_SC_OPEN_MAX); fd >= 0; fd--) {
+		close (fd);
+	}
+
+	// 8. redirect stdin, stdout and stderr to /dev/null
+	if (open ("/dev/null", O_RDWR) != STDIN_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stdin");
+		exit (1);
+	}
+	if (dup2 (STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stdout");
+		exit (1);
+	}
+	if (dup2 (STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stderr");
+		exit (1);
+	}
+
+	// 9. option: open syslog for message logging
+	openlog (NULL, LOG_NDELAY | LOG_PID, LOG_DAEMON); 
+	syslog (LOG_INFO, "Daemon has started...");
+ 
+	// 10. option: get effective user and group id for appropriate's one
+	struct passwd* pwd = getpwnam ("daemon");
+	if (pwd == 0) {
+		syslog (LOG_ERR, "ERROR while reading daemon password file entry");
+		exit (1);
+	}
+
+	// 11. option: change root directory
+	if (chroot (".") == -1) {
+		syslog (LOG_ERR, "ERROR while changing to new root directory");
+		exit (1);
+	}
+
+	// 12. option: change effective user and group id for appropriate's one
+	if (setegid (pwd->pw_gid) == -1) {
+		syslog (LOG_ERR, "ERROR while setting new effective group id");
+		exit (1);
+	}
+	if (seteuid (pwd->pw_uid) == -1) {
+		syslog (LOG_ERR, "ERROR while setting new effective user id");
+		exit (1);
+	}
+
+	// 13. implement daemon body...
+	int t = 30;
+	do {
+		t = sleep(t);
+	} while (t > 0);
+
+	syslog (LOG_INFO, "daemon stopped. Number of signals catched=%d\n", signal_catched);
+	closelog();
+
+	return 0;
+}

src/dot-vscode/deploy.sh

@@ -0,0 +1,24 @@
+set -o errexit
+set -o pipefail
+set -o nounset
+# set -o xtrace
+
+__dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+__root="$(cd "$(dirname "${__dir}")" && pwd)"
+
+targets="""
+backtrace
+core_dumps
+daemon
+fibonacci
+memory_leaks
+process
+system_calls
+tracing
+"""
+
+for i in $targets; do
+    mkdir -p $__root/$i/.vscode
+    cp $__dir/launch.json $__root/$i/.vscode
+    cp $__dir/tasks.json $__root/$i/.vscode
+done

src/dot-vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/dot-vscode/launch.json_presque

@@ -0,0 +1,43 @@
+{
+  // Use IntelliSense to learn about possible attributes.
+  // Hover to view descriptions of existing attributes.
+  // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "(gdb) Launch",
+      "type": "cppdbg",
+      "request": "launch",
+      "program": "app",
+      "args": [
+        "2"
+      ],
+      "stopAtEntry": true,
+      "cwd": "${workspaceFolder}",
+      "environment": [],
+      "externalConsole": false,
+      "MIMode": "gdb",
+      "setupCommands": [
+        {
+          "description": "Enable pretty-printing for gdb",
+          "text": "-enable-pretty-printing",
+          "ignoreFailures": true
+        }
+      ],
+      // "miDebuggerServerAddress": "192.168.0.14:1234",
+      // "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb",
+      "pipeTransport": {
+        // "pipeCwd": "/usr/bin",
+        "pipeProgram": "/usr/bin/ssh",
+        "pipeArgs": [
+          "root@192.168.0.14"
+        ],
+        "debuggerPath": "/usr/bin/gdb"
+        // "debuggerPath": "stdbuf -i0 -o0 -e0 /usr/bin/gdb"
+      },
+      // "logging": {
+      //   "engineLogging": true,
+      // },
+    }
+  ]
+}

src/dot-vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/fibonacci/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/fibonacci/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app 2'"]
+       }
+    ]
+}

src/fibonacci/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/fibonacci/fibonacci.c

@@ -0,0 +1,88 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	Fibonacci numbers: a simple demo program to exercice debugging
+ * 		facilities on embedded Linux system.
+ *
+ *		-->> tracing with printf
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/**
+ * The Fibonacci numbers form a sequence of integers, mathematically defined by
+ *   F(0)=0; F(1)=1; F(n) = F(n - 1) + F(n - 2) for n > 1.
+ *
+ * This results in the following sequence of numbers: 0, 1, 1, 2, 3, 5, 8, 13,
+ *    21, 34, 55, 89, 144, 233, 377, 610, 987, ...
+ * so that each new number is the sum of the previous two, after seeding the
+ * sequence with the starting pair 0, 1.
+ *
+ * @param n value for which the Fibonacci number should be computed
+ * @return Fibonacci number
+ */
+long fibonacci_r(long n)
+{
+    if (n <= 1)
+        return n;
+    return fibonacci_r(n - 1) + fibonacci_r(n - 2);
+}
+
+long fibonacci_i(long n)
+{
+    long f0 = 0;
+    long f1 = 1;
+    while (n > 0)
+    {
+        f1 = f1 + f0;
+        f0 = f1 - f0; // WAT !!!
+        n--;
+    }
+    return f0;
+}
+
+/**
+ * Main program computing the Fibonacci numbers for a given sequence starting
+ * from 0 to a number specified at the command line.
+ */
+int main(int argc, char **argv)
+{
+    long n = 0;
+    long i = 0;
+
+    if (argc == 2)
+    {
+        n = atol(argv[1]);
+    }
+
+    printf("%s, %d, %s, %s\n", __FILE__, __LINE__, __DATE__, __TIME__);
+    printf("The first %ld Fibonacci numbers are:\n", n);
+
+    for (i = 0; i < n; i++)
+    {
+        printf("%ld%s", fibonacci_i(i), i < n-1 ? ", " : "");
+    }
+    printf("\n");
+
+    return 0;
+}

src/memory_leaks/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/memory_leaks/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/memory_leaks/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/memory_leaks/mem_leaks.c

@@ -0,0 +1,113 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	Memory leak demo program 
+ *		call this demo program with 
+ *              $ valgrind  --leak-check=full ./app_a
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+
+#ifdef DEBUG
+#define TRACE(x) printf x
+#else
+#define TRACE(x)
+#endif
+
+struct alpha
+{ 
+	int attr;
+	struct alpha* next;
+};
+
+
+void alloc1 (struct alpha** root)
+{
+	static int cnt=0;
+
+	struct alpha* ele = malloc (sizeof(*ele));
+	ele->next = 0;
+	ele->attr = cnt++;
+	if (*root == 0) {
+		*root = ele;
+	} else {
+		struct alpha* n = *root;
+		while (n->next != 0) n = n->next;
+		n->next = ele;
+	}
+}
+
+void alloc2(struct alpha** root)
+{
+	static int cnt=0;
+
+	struct alpha* ele = malloc (sizeof(*ele));
+	ele->next = 0;
+	ele->attr = cnt++;
+	if (*root == 0) {
+		*root = ele;
+	} else {
+		struct alpha* n = *root;
+		while (n->next != 0) n = n->next;
+		n->next = ele;
+	}
+}
+
+void alloc(struct alpha** root)
+{
+	static int x=0;
+
+	if (x == 0) alloc1(root); 
+	else alloc2 (root);
+
+	x = (x + 1) % 2;
+}
+
+void dealloc(struct alpha** root)
+{
+	struct alpha* ele = *root;
+	if (*root != 0) *root = ele->next;
+	free (ele);
+}
+
+int main ()
+{
+	struct alpha* root = 0;
+
+	for (int i=0; i<4000; i++) alloc (&root);
+
+	struct alpha* p = root;
+	int i = 0;
+	while (p != 0) {
+		TRACE (("ele %2d, attr=%2d, ptr=%p\n", i, p->attr, p));
+		p = p->next;
+		i++;
+	}
+
+	for (int i=0; i<15; i++) dealloc (&root);
+
+	return 0;
+}
+
+

src/process/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/process/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/process/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/process/process.c

@@ -0,0 +1,133 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	This module implements a simple application to be launched from
+ *		/etc/inttab.
+ *		-->> tracing with syslog
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+#define _XOPEN_SOURCE 600
+#define _DEFAULT_SOURCE
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <grp.h>
+#include <pwd.h>
+#include <signal.h>
+#include <syslog.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#define UNUSED(x) (void)(x)
+
+static int signal_catched = 0; 
+
+static void catch_signal (int signal)
+{
+	syslog (LOG_INFO, "signal=%d catched\n", signal);
+	signal_catched++;
+}
+
+int main(int argc, char* argv[])
+{
+	UNUSED(argc); UNUSED(argv);
+	
+	// daemon's steps 1 to 3 skipt
+
+	// 4. capture all required signals
+	struct sigaction act = {.sa_handler = catch_signal,};
+	sigaction (SIGHUP,  &act, NULL);  //  1 - hangup
+	sigaction (SIGINT,  &act, NULL);  //  2 - terminal interrupt
+	sigaction (SIGQUIT, &act, NULL);  //  3 - terminal quit
+	sigaction (SIGABRT, &act, NULL);  //  6 - abort
+	sigaction (SIGTERM, &act, NULL);  // 15 - termination
+	sigaction (SIGTSTP, &act, NULL);  // 19 - terminal stop signal
+
+	// 5. update file mode creation mask
+	umask(0027);
+
+	// 6. change working directory to appropriate place
+	if (chdir ("/") == -1) {
+		syslog (LOG_ERR, "ERROR while changing to working directory"); 
+		exit (1);
+	}
+
+	// 7. close all open file descriptors
+	for (int fd = sysconf(_SC_OPEN_MAX); fd >= 0; fd--) {
+		close (fd);
+	}
+
+	// 8. redirect stdin, stdout and stderr to /dev/null
+	if (open ("/dev/null", O_RDWR) != STDIN_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stdin");
+		exit (1);
+	}
+	if (dup2 (STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stdout");
+		exit (1);
+	}
+	if (dup2 (STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
+		syslog (LOG_ERR, "ERROR while opening '/dev/null' for stderr");
+		exit (1);
+	}
+
+	// 9. option: open syslog for message logging
+	openlog (NULL, LOG_NDELAY | LOG_PID, LOG_DAEMON); 
+	syslog (LOG_INFO, "Daemon has started...");
+ 
+	// 10. option: get effective user and group id for appropriate's one
+	struct passwd* pwd = getpwnam ("daemon");
+	if (pwd == 0) {
+		syslog (LOG_ERR, "ERROR while reading daemon password file entry");
+		exit (1);
+	}
+
+	// 11. option: change root directory
+	if (chroot (".") == -1) {
+		syslog (LOG_ERR, "ERROR while changing to new root directory");
+		exit (1);
+	}
+
+	// 12. option: change effective user and group id for appropriate's one
+	if (setegid (pwd->pw_gid) == -1) {
+		syslog (LOG_ERR, "ERROR while setting new effective group id");
+		exit (1);
+	}
+	if (seteuid (pwd->pw_uid) == -1) {
+		syslog (LOG_ERR, "ERROR while setting new effective user id");
+		exit (1);
+	}
+ 
+	// 13. implement daemon body...
+	int t = 30;
+	do {
+		t = sleep(t);
+	} while (t > 0);
+
+	syslog (LOG_INFO, "daemon stopped. Number of signals catched=%d\n", signal_catched);
+	closelog();
+
+	return 0;
+}

src/system_calls/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/system_calls/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/system_calls/Makefile

@@ -0,0 +1,5 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/system_calls/syscall.c

@@ -0,0 +1,58 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	System call demo program 
+ *		call this demo program with 
+ *              # strace ./app_a
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <errno.h>
+#include <libgen.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+int main() 
+{	
+	int temp = 99000;
+	int f = open("/sys/class/thermal/thermal_zone0/temp", O_RDONLY);
+	if (f >= 0) {
+		char val[50] = "";
+		ssize_t r = read (f, val, sizeof(val));
+		close (f);
+		if (r > 0) {
+			temp = atoi(val);
+		}
+	}
+	printf ("current temperature: %d.%02d degree Celcius\n", 
+		temp/1000, (temp/10)%100);
+
+	return 0;
+}
+
+

src/tracing/.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+
+       {
+         "name": "(gdb) Launch",
+         "type": "cppdbg",
+         "request": "launch",
+         "program": "${workspaceFolder}/app",
+         "stopAtEntry": true,
+         "cwd": "${workspaceFolder}",
+         "externalConsole": false,
+         "MIMode": "gdb",
+         "miDebuggerServerAddress": "192.168.0.14:1234",
+         "miDebuggerPath": "/buildroot/output/host/bin/aarch64-linux-gdb"
+       }
+    ]
+}

src/tracing/.vscode/tasks.json

@@ -0,0 +1,14 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+       {
+         "label": "gdbserver",
+         "type": "shell",
+         "command": [
+             "ssh -t root@192.168.0.14 '/usr/bin/gdbserver :1234", 
+             "${workspaceFolder}/app'"]
+       }
+    ]
+}

src/tracing/Makefile

@@ -0,0 +1,9 @@
+EXE=app
+SRCS=$(wildcard *.c)
+
+ifneq ($(DEBUG),)
+EXTRA_CFLAGS+=-DDEBUG
+endif
+
+# Include the standard application Makefile for the CSEL1 labs
+include ../appl.mk

src/tracing/fibonacci.c

@@ -0,0 +1,79 @@
+/**
+ * Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Module:	MA-CSEL1 - Building Embedded Systems under Linux
+ *
+ * Abstract: 	Introduction to the Embedded Linux Development Environment
+ *
+ * Purpose:	Fibonacci numbers: a simple demo program to exercice debugging
+ * 		facilities on embedded Linux system.
+ *
+ *		-->> tracing with conditional printf
+ *
+ * Autĥor:	Daniel Gachet
+ * Date:	28.08.2015
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifdef DEBUG
+#define TRACE(x) printf x
+#else
+#define TRACE(X)
+#endif
+    
+/**
+ * The Fibonacci numbers form a sequence of integers, mathematically defined by 
+ *   F(0)=0; F(1)=1; F(n) = F(n - 1) + F(n - 2) for n > 1.
+ *  
+ * This results in the following sequence of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 
+ *    21, 34, 55, 89, 144, 233, 377, 610, 987, ...
+ * so that each new number is the sum of the previous two, after seeding the 
+ * sequence with the starting pair 0, 1.
+ *  
+ * @param n value for which the Fibonacci number should be computed
+ * @return Fibonacci number 
+ */
+long fibonacci(long n)
+{
+  if (n <= 1) return n;
+  return fibonacci(n-1)+fibonacci(n-2);
+}
+
+
+/**
+ * Main program computing the Fibonacci numbers for a given sequence starting 
+ * from 0 to a number specified at the command line. 
+ */
+int main (int argc, char** argv)
+{
+    long n = 0;
+    long i = 0;
+
+    if (argc == 2) {
+        n = atol(argv[1]);
+    }
+
+    TRACE(("%s, %d, %s, %s\n", __FILE__, __LINE__, __DATE__, __TIME__));
+    printf("The first %ld Fibonacci numbers are:\n", n);
+
+    for (i=0; i<=n; i++) {
+        printf("%ld, ", fibonacci(i));
+    }
+    printf("\n");
+
+    return 0;
+}