adb/SERVICES.TXT - platform/system/core - Gitiles

 This file tries to document all requests a client can make
 to the ADB server of an adbd daemon. See the OVERVIEW.TXT document
 to understand what's going on here.

 HOST SERVICES:

 host:version
     Ask the ADB server for its internal version number.

     As a special exception, the server will respond with a 4-byte
     hex string corresponding to its internal version number, without
     any OKAY or FAIL.

 host:kill
     Ask the ADB server to quit immediately. This is used when the
     ADB client detects that an obsolete server is running after an
     upgrade.

 host:devices
     Ask to return the list of available Android devices and their
     state. After the OKAY, this is followed by a 4-byte hex len,
     and a string that will be dumped as-is by the client, then
     the connection is closed

 host:track-devices
     This is a variant of host:devices which doesn't close the
     connection. Instead, a new device list description is sent
     each time a device is added/removed or the state of a given
     device changes (hex4 + content). This allows tools like DDMS
     to track the state of connected devices in real-time without
     polling the server repeatedly.

 host:emulator:<port>
     This is a special query that is sent to the ADB server when a
     new emulator starts up. <port> is a decimal number corresponding
     to the emulator's ADB control port, i.e. the TCP port that the
     emulator will forward automatically to the adbd daemon running
     in the emulator system.

     This mechanism allows the ADB server to know when new emulator
     instances start.

 host:transport:<serial-number>
     Ask to switch the connection to the device/emulator identified by
     <serial-number>. After the OKAY response, every client request will
     be sent directly to the adbd daemon running on the device.
     (Used to implement the -s option)

 host:transport-usb
     Ask to switch the connection to one device connected through USB
     to the host machine. This will fail if there are more than one such
     devices. (Used to implement the -d convenience option)

 host:transport-local
     Ask to switch the connection to one emulator connected through TCP.
     This will fail if there is more than one such emulator instance
     running. (Used to implement the -e convenience option)

 host:transport-any
     Another host:transport variant. Ask to switch the connection to
     either the device or emulator connect to/running on the host.
     Will fail if there is more than one such device/emulator available.
     (Used when neither -s, -d or -e are provided)

 host-serial:<serial-number>:<request>
     This is a special form of query, where the 'host-serial:<serial-number>:'
     prefix can be used to indicate that the client is asking the ADB server
     for information related to a specific device. <request> can be in one
     of the format described below.

 host-usb:<request>
     A variant of host-serial used to target the single USB device connected
     to the host. This will fail if there is none or more than one.

 host-local:<request>
     A variant of host-serial used to target the single emulator instance
     running on the host. This will fail if therre is none or more than one.

 host:<request>
     When asking for information related to a device, 'host:' can also be
     interpreted as 'any single device or emulator connected to/running on
     the host'.

 <host-prefix>:get-product
     XXX

 <host-prefix>:get-serialno
     Returns the serial number of the corresponding device/emulator.
     Note that emulator serial numbers are of the form "emulator-5554"

 <host-prefix>:get-state
     Returns the state of a given device as a string.

 <host-prefix>:forward:<local>;<remote>
     Asks the ADB server to forward local connections from <local>
     to the <remote> address on a given device.

     There, <host-prefix> can be one of the
     host-serial/host-usb/host-local/host prefixes as described previously
     and indicates which device/emulator to target.

     the format of <local> is one of:

         tcp:<port>      -> TCP connection on localhost:<port>
         local:<path>    -> Unix local domain socket on <path>

     the format of <remote> is one of:

         tcp:<port>      -> TCP localhost:<port> on device
         local:<path>    -> Unix local domain socket on device
         jdwp:<pid>      -> JDWP thread on VM process <pid>

     or even any one of the local services described below.


 LOCAL SERVICES:

 All the queries below assumed that you already switched the transport
 to a real device, or that you have used a query prefix as described
 above.

 shell:command arg1 arg2 ...
     Run 'command arg1 arg2 ...' in a shell on the device, and return
     its output and error streams. Note that arguments must be separated
     by spaces. If an argument contains a space, it must be quoted with
     double-quotes. Arguments cannot contain double quotes or things
     will go very wrong.

     Note that this is the non-interactive version of "adb shell"

 shell:
     Start an interactive shell session on the device. Redirect
     stdin/stdout/stderr as appropriate. Note that the ADB server uses
     this to implement "adb shell", but will also cook the input before
     sending it to the device (see interactive_shell() in commandline.c)

 remount:
     Ask adbd to remount the device's filesystem in read-write mode,
     instead of read-only. This is usually necessary before performing
     an "adb sync" or "adb push" request.

     This request may not succeed on certain builds which do not allow
     that.

 dev:<path>
     Opens a device file and connects the client directly to it for
     read/write purposes. Useful for debugging, but may require special
     priviledges and thus may not run on all devices. <path> is a full
     path from the root of the filesystem.

 tcp:<port>
     Tries to connect to tcp port <port> on localhost.

 tcp:<port>:<server-name>
     Tries to connect to tcp port <port> on machine <server-name> from
     the device. This can be useful to debug some networking/proxy
     issues that can only be revealed on the device itself.

 local:<path>
     Tries to connect to a Unix domain socket <path> on the device

 localreserved:<path>
 localabstract:<path>
 localfilesystem:<path>
     Variants of local:<path> that are used to access other Android
     socket namespaces.

 log:<name>
     Opens one of the system logs (/dev/log/<name>) and allows the client
     to read them directly. Used to implement 'adb logcat'. The stream
     will be read-only for the client.

 framebuffer:
     This service is used to send snapshots of the framebuffer to a client.
     It requires sufficient priviledges but works as follow:

       After the OKAY, the service sends 16-byte binary structure
       containing the following fields (little-endian format):

             depth:   uint32_t:    framebuffer depth
             size:    uint32_t:    framebuffer size in bytes
             width:   uint32_t:    framebuffer width in pixels
             height:  uint32_t:    framebuffer height in pixels

       With the current implementation, depth is always 16, and
       size is always width*height*2

       Then, each time the client wants a snapshot, it should send
       one byte through the channel, which will trigger the service
       to send it 'size' bytes of framebuffer data.

       If the adbd daemon doesn't have sufficient priviledges to open
       the framebuffer device, the connection is simply closed immediately.

 dns:<server-name>
     This service is an exception because it only runs within the ADB server.
     It is used to implement USB networking, i.e. to provide a network connection
     to the device through the host machine (note: this is the exact opposite of
     network thetering).

     It is used to perform a gethostbyname(<address>) on the host and return
     the corresponding IP address as a 4-byte string.

 recover:<size>
     This service is used to upload a recovery image to the device. <size>
     must be a number corresponding to the size of the file. The service works
     by:

        - creating a file named /tmp/update
        - reading 'size' bytes from the client and writing them to /tmp/update
        - when everything is read succesfully, create a file named /tmp/update.start

     This service can only work when the device is in recovery mode. Otherwise,
     the /tmp directory doesn't exist and the connection will be closed immediately.

 jdwp:<pid>
     Connects to the JDWP thread running in the VM of process <pid>.

 track-jdwp
     This is used to send the list of JDWP pids periodically to the client.
     The format of the returned data is the following:

         <hex4>:    the length of all content as a 4-char hexadecimal string
         <content>: a series of ASCII lines of the following format:
                         <pid> "\n"

     This service is used by DDMS to know which debuggable processes are running
     on the device/emulator.

     Note that there is no single-shot service to retrieve the list only once.

 sync:
     This starts the file synchronisation service, used to implement "adb push"
     and "adb pull". Since this service is pretty complex, it will be detailed
     in a companion document named SYNC.TXT
	This file tries to document all requests a client can make
	to the ADB server of an adbd daemon. See the OVERVIEW.TXT document
	to understand what's going on here.

	HOST SERVICES:

	host:version
	Ask the ADB server for its internal version number.

	As a special exception, the server will respond with a 4-byte
	hex string corresponding to its internal version number, without
	any OKAY or FAIL.

	host:kill
	Ask the ADB server to quit immediately. This is used when the
	ADB client detects that an obsolete server is running after an
	upgrade.

	host:devices
	Ask to return the list of available Android devices and their
	state. After the OKAY, this is followed by a 4-byte hex len,
	and a string that will be dumped as-is by the client, then
	the connection is closed

	host:track-devices
	This is a variant of host:devices which doesn't close the
	connection. Instead, a new device list description is sent
	each time a device is added/removed or the state of a given
	device changes (hex4 + content). This allows tools like DDMS
	to track the state of connected devices in real-time without
	polling the server repeatedly.

	host:emulator:<port>
	This is a special query that is sent to the ADB server when a
	new emulator starts up. <port> is a decimal number corresponding
	to the emulator's ADB control port, i.e. the TCP port that the
	emulator will forward automatically to the adbd daemon running
	in the emulator system.

	This mechanism allows the ADB server to know when new emulator
	instances start.

	host:transport:<serial-number>
	Ask to switch the connection to the device/emulator identified by
	<serial-number>. After the OKAY response, every client request will
	be sent directly to the adbd daemon running on the device.
	(Used to implement the -s option)

	host:transport-usb
	Ask to switch the connection to one device connected through USB
	to the host machine. This will fail if there are more than one such
	devices. (Used to implement the -d convenience option)

	host:transport-local
	Ask to switch the connection to one emulator connected through TCP.
	This will fail if there is more than one such emulator instance
	running. (Used to implement the -e convenience option)

	host:transport-any
	Another host:transport variant. Ask to switch the connection to
	either the device or emulator connect to/running on the host.
	Will fail if there is more than one such device/emulator available.
	(Used when neither -s, -d or -e are provided)

	host-serial:<serial-number>:<request>
	This is a special form of query, where the 'host-serial:<serial-number>:'
	prefix can be used to indicate that the client is asking the ADB server
	for information related to a specific device. <request> can be in one
	of the format described below.

	host-usb:<request>
	A variant of host-serial used to target the single USB device connected
	to the host. This will fail if there is none or more than one.

	host-local:<request>
	A variant of host-serial used to target the single emulator instance
	running on the host. This will fail if therre is none or more than one.

	host:<request>
	When asking for information related to a device, 'host:' can also be
	interpreted as 'any single device or emulator connected to/running on
	the host'.

	<host-prefix>:get-product
	XXX

	<host-prefix>:get-serialno
	Returns the serial number of the corresponding device/emulator.
	Note that emulator serial numbers are of the form "emulator-5554"

	<host-prefix>:get-state
	Returns the state of a given device as a string.

	<host-prefix>:forward:<local>;<remote>
	Asks the ADB server to forward local connections from <local>
	to the <remote> address on a given device.

	There, <host-prefix> can be one of the
	host-serial/host-usb/host-local/host prefixes as described previously
	and indicates which device/emulator to target.

	the format of <local> is one of:

	tcp:<port> -> TCP connection on localhost:<port>
	local:<path> -> Unix local domain socket on <path>

	the format of <remote> is one of:

	tcp:<port> -> TCP localhost:<port> on device
	local:<path> -> Unix local domain socket on device
	jdwp:<pid> -> JDWP thread on VM process <pid>

	or even any one of the local services described below.



	LOCAL SERVICES:

	All the queries below assumed that you already switched the transport
	to a real device, or that you have used a query prefix as described
	above.

	shell:command arg1 arg2 ...
	Run 'command arg1 arg2 ...' in a shell on the device, and return
	its output and error streams. Note that arguments must be separated
	by spaces. If an argument contains a space, it must be quoted with
	double-quotes. Arguments cannot contain double quotes or things
	will go very wrong.

	Note that this is the non-interactive version of "adb shell"

	shell:
	Start an interactive shell session on the device. Redirect
	stdin/stdout/stderr as appropriate. Note that the ADB server uses
	this to implement "adb shell", but will also cook the input before
	sending it to the device (see interactive_shell() in commandline.c)

	remount:
	Ask adbd to remount the device's filesystem in read-write mode,
	instead of read-only. This is usually necessary before performing
	an "adb sync" or "adb push" request.

	This request may not succeed on certain builds which do not allow
	that.

	dev:<path>
	Opens a device file and connects the client directly to it for
	read/write purposes. Useful for debugging, but may require special
	priviledges and thus may not run on all devices. <path> is a full
	path from the root of the filesystem.

	tcp:<port>
	Tries to connect to tcp port <port> on localhost.

	tcp:<port>:<server-name>
	Tries to connect to tcp port <port> on machine <server-name> from
	the device. This can be useful to debug some networking/proxy
	issues that can only be revealed on the device itself.

	local:<path>
	Tries to connect to a Unix domain socket <path> on the device

	localreserved:<path>
	localabstract:<path>
	localfilesystem:<path>
	Variants of local:<path> that are used to access other Android
	socket namespaces.

	log:<name>
	Opens one of the system logs (/dev/log/<name>) and allows the client
	to read them directly. Used to implement 'adb logcat'. The stream
	will be read-only for the client.

	framebuffer:
	This service is used to send snapshots of the framebuffer to a client.
	It requires sufficient priviledges but works as follow:

	After the OKAY, the service sends 16-byte binary structure
	containing the following fields (little-endian format):

	depth: uint32_t: framebuffer depth
	size: uint32_t: framebuffer size in bytes
	width: uint32_t: framebuffer width in pixels
	height: uint32_t: framebuffer height in pixels

	With the current implementation, depth is always 16, and
	size is always widthheight2

	Then, each time the client wants a snapshot, it should send
	one byte through the channel, which will trigger the service
	to send it 'size' bytes of framebuffer data.

	If the adbd daemon doesn't have sufficient priviledges to open
	the framebuffer device, the connection is simply closed immediately.

	dns:<server-name>
	This service is an exception because it only runs within the ADB server.
	It is used to implement USB networking, i.e. to provide a network connection
	to the device through the host machine (note: this is the exact opposite of
	network thetering).

	It is used to perform a gethostbyname(<address>) on the host and return
	the corresponding IP address as a 4-byte string.

	recover:<size>
	This service is used to upload a recovery image to the device. <size>
	must be a number corresponding to the size of the file. The service works
	by:

	- creating a file named /tmp/update
	- reading 'size' bytes from the client and writing them to /tmp/update
	- when everything is read succesfully, create a file named /tmp/update.start

	This service can only work when the device is in recovery mode. Otherwise,
	the /tmp directory doesn't exist and the connection will be closed immediately.

	jdwp:<pid>
	Connects to the JDWP thread running in the VM of process <pid>.

	track-jdwp
	This is used to send the list of JDWP pids periodically to the client.
	The format of the returned data is the following:

	<hex4>: the length of all content as a 4-char hexadecimal string
	<content>: a series of ASCII lines of the following format:
	<pid> "\n"

	This service is used by DDMS to know which debuggable processes are running
	on the device/emulator.

	Note that there is no single-shot service to retrieve the list only once.

	sync:
	This starts the file synchronisation service, used to implement "adb push"
	and "adb pull". Since this service is pretty complex, it will be detailed
	in a companion document named SYNC.TXT