Clean up reading and writing in init.
This isn't particularly useful in and of itself, but it does introduce the
first (trivial) unit test, improves the documentation (including details
about how to debug init crashes), and made me aware of how unpleasant the
existing parser is.
I also fixed a bug in passing --- unless you thought the "peboot" and "pm"
commands were features...
Bug: 19217569
Change-Id: I6ab76129a543ce3ed3dab52ef2c638009874c3de
diff --git a/init/readme.txt b/init/readme.txt
index e5406ed..16a9186 100644
--- a/init/readme.txt
+++ b/init/readme.txt
@@ -191,10 +191,12 @@
on property:ro.boot.myfancyhardware=1
enable my_fancy_service_for_my_fancy_hardware
-
insmod <path>
Install the module at <path>
+loglevel <level>
+ Sets the kernel log level to level. Properties are expanded within <level>.
+
mkdir <path> [mode] [owner] [group]
Create a directory at <path>, optionally with the given mode, owner, and
group. If not provided, the directory is created with permissions 755 and
@@ -229,7 +231,8 @@
TBD
setprop <name> <value>
- Set system property <name> to <value>.
+ Set system property <name> to <value>. Properties are expanded
+ within <value>.
setrlimit <resource> <cur> <max>
Set the rlimit for a resource.
@@ -259,9 +262,10 @@
or the timeout has been reached. If timeout is not specified it
currently defaults to five seconds.
-write <path> <string>
- Open the file at <path> and write a string to it with write(2)
- without appending.
+write <path> <content>
+ Open the file at <path> and write a string to it with write(2).
+ If the file does not exist, it will be created. If it does exist,
+ it will be truncated. Properties are expanded within <content>.
Properties
@@ -338,8 +342,23 @@
---------------
By default, programs executed by init will drop stdout and stderr into
/dev/null. To help with debugging, you can execute your program via the
-Andoird program logwrapper. This will redirect stdout/stderr into the
+Android program logwrapper. This will redirect stdout/stderr into the
Android logging system (accessed via logcat).
For example
service akmd /system/bin/logwrapper /sbin/akmd
+
+For quicker turnaround when working on init itself, use:
+
+ mm
+ m ramdisk-nodeps
+ m bootimage-nodeps
+ adb reboot bootloader
+ fastboot boot $ANDROID_PRODUCT_OUT/boot.img
+
+Alternatively, use the emulator:
+
+ emulator -partition-size 1024 -verbose -show-kernel -no-window
+
+You might want to call klog_set_level(6) after the klog_init() call
+so you see the kernel logging in dmesg (or the emulator output).