[Android] Add support for custom startup scripts (#6275)

Add the possibility to run *.sh scripts:

After an update of koreader all *.sh scripts in /sdcard/koreader/scripts.afterupdate
are executed.

On every start of koreader run all *.sh scripts in /sdcard/koreader/scripts.always

Makefile

@@ -94,6 +94,8 @@ endif
 ifdef ANDROID
 	cd $(INSTALL_DIR)/koreader && \
 		ln -sf ../../$(ANDROID_DIR)/*.lua .
+	@echo "[*] Install afterupdate marker"
+	@echo "# If this file is here, there are no afterupdate scripts in /sdcard/koreader/scripts/afterupdate." > $(INSTALL_DIR)/koreader/afterupdate.marker
 endif
 ifdef WIN32
 	@echo "[*] Install runtime libraries for win32..."
@@ -105,7 +107,7 @@ endif
 	@# purge deleted plugins
 	for d in $$(ls $(INSTALL_DIR)/koreader/plugins); do \
 		test -d plugins/$$d || rm -rf $(INSTALL_DIR)/koreader/plugins/$$d ; done
-	@echo "[*] Installresources"
+	@echo "[*] Install resources"
 	$(RCP) -pL resources/fonts/. $(INSTALL_DIR)/koreader/fonts/.
 	install -d $(INSTALL_DIR)/koreader/{screenshots,data/{dict,tessdata},fonts/host,ota}
 ifeq ($(IS_RELEASE),1)

platform/android/llapp_main.lua

@@ -1,6 +1,7 @@
 local android = require("android")
 android.dl.library_path = android.dl.library_path .. ":" .. android.dir .. "/libs"
 
+local lfs = require("libs/libkoreader-lfs")
 local ffi = require("ffi")
 local dummy = require("ffi/posix_h")
 local C = ffi.C
@@ -15,6 +16,37 @@ end
 -- path to primary external storage partition
 local path = android.getExternalStoragePath()
 
+-- run user shell scripts
+local function runUserScripts(dir)
+    for entry in lfs.dir(dir) do
+        if entry ~= "." and entry ~= ".." then
+            local fullpath = dir .. "/" .. entry
+            local mode = lfs.attributes(fullpath).mode
+            if mode == "file" and fullpath:match(".sh$") then
+                android.execute("sh", fullpath, path .. "/koreader", android.dir)
+            elseif mode == "directory" then
+                runUserScripts(fullpath) -- recurse into next directory
+            end
+        end
+    end
+end
+
+-- scripts executed once after an update of koreader
+local run_once_scripts = path .. "/koreader/scripts.afterupdate"
+if lfs.attributes(run_once_scripts, "mode") == "directory" then
+    local afterupdate_marker = android.dir .. "/afterupdate.marker"
+    if lfs.attributes(afterupdate_marker, "mode") ~= nil then
+         runUserScripts(run_once_scripts)
+         android.execute("rm", afterupdate_marker)
+     end
+end
+
+-- scripts executed every start of koreader
+local run_always_scripts = path .. "/koreader/scripts.always"
+if lfs.attributes(run_always_scripts, "mode") == "directory" then
+    runUserScripts(run_always_scripts)
+end
+ 
 -- run koreader patch before koreader startup
 pcall(dofile, path.."/koreader/patch.lua")