Read Arduino installation path from preference file

[sudar]

From this commit Arduino started to place the Arduino installation path in the preference file.

Try to read the Arduino installation path, if the user has not explicitly set it.

[sej7278]

its explained here most notable is runtime.ide.path

[sej7278]

the problem with this now is that its versionned, so we have:

last.ide.1.6.1.daterun=1427555323
last.ide.1.6.1.hardwarepath=~/arduino-1.6.1/hardware
last.ide.1.6.3.daterun=1428863136
last.ide.1.6.3.hardwarepath=~/arduino-1.6.3/hardware

so we can't use it to find the arduino installation path without requiring the user to specify the version s/he wants to use, and we can't auto-detect the version from the installation path (chicken & egg).

we could look for the last version run or the highest version number, but that's a fair bit of logic for a makefile, and it only works for 1.5+, and relies on people actually using the IDE

[sej7278]

to find the highest ide version used and its path, you can use the following:

$ grep hardwarepath ~/.arduino15/preferences.txt 
last.ide.1.6.1.hardwarepath=/home/user/arduino/arduino-1.6.1/hardware
last.ide.1.6.3.hardwarepath=/home/user/arduino/arduino-1.6.3/hardware
last.ide.1.6.4.hardwarepath=/home/user/arduino/arduino-1.6.4/hardware

$ grep hardwarepath ~/.arduino15/preferences.txt | tail -1 | awk -F= {'print $2'}
/home/user/arduino/arduino-1.6.4/hardware

$ grep hardwarepath ~/.arduino15/preferences.txt | tail -1 | awk -F= {'print $1'} | sed s/[^0-9]*//g
164

[sej7278]

this patch adds support for finding ARDUINO_DIR and ARDUINO_VERSION from the preferences but it still seems a bit pointless - as we're assuming the path to preferences.txt and assuming its 1.5+, also is "grep -h" portable?

diff --git a/Arduino.mk b/Arduino.mk
index 936645a..331cd02 100644
--- a/Arduino.mk
+++ b/Arduino.mk
@@ -277,6 +277,13 @@ ifndef ARDUINO_VERSION
     # Works for 1.0 and 1.0.1
     VERSION_FILE := $(ARDUINO_DIR)/lib/version.txt
     AUTO_ARDUINO_VERSION := $(shell [ -e $(VERSION_FILE) ] && cat $(VERSION_FILE) | sed -e 's/^[0-9]://g' -e 's/[.]//g' -e 's/$$/0000/' | head -c3)
+
+    # only works for 1.5+ if ide has previously been run
+    ifndef AUTO_ARDUINO_VERSION
+        AUTO_ARDUINO_VERSION := $(shell grep -h hardwarepath $(HOME)/.arduino15/preferences.txt \
+            $(HOME)/Library/Arduino15/preferences.txt 2> /dev/null | tail -1 | awk -F= {'print $$1'} | sed s/[^0-9]*//g)
+    endif
+
     ifdef AUTO_ARDUINO_VERSION
         ARDUINO_VERSION = $(AUTO_ARDUINO_VERSION)
         $(call show_config_variable,ARDUINO_VERSION,[AUTODETECTED])
diff --git a/Common.mk b/Common.mk
index 7eda5ea..a16c58a 100644
--- a/Common.mk
+++ b/Common.mk
@@ -69,7 +69,10 @@ ifndef ARDUINO_DIR
     AUTO_ARDUINO_DIR := $(firstword \
         $(call dir_if_exists,/usr/share/arduino) \
         $(call dir_if_exists,/Applications/Arduino.app/Contents/Resources/Java) \
-        $(call dir_if_exists,/Applications/Arduino.app/Contents/Java) )
+        $(call dir_if_exists,/Applications/Arduino.app/Contents/Java) \
+        $(call dir_if_exists,$(abspath $(dir $(shell grep -h hardwarepath $(HOME)/.arduino15/preferences.txt \
+            $(HOME)/Library/Arduino15/preferences.txt 2> /dev/null | tail -1 | awk -F= {'print $$2'})/../))) )
+
     ifdef AUTO_ARDUINO_DIR
        ARDUINO_DIR = $(AUTO_ARDUINO_DIR)
        $(call show_config_variable,ARDUINO_DIR,[AUTODETECTED])