diff options
Diffstat (limited to 'lib/inets/doc/src/tftp.xml')
| -rw-r--r-- | lib/inets/doc/src/tftp.xml | 647 |
1 files changed, 0 insertions, 647 deletions
diff --git a/lib/inets/doc/src/tftp.xml b/lib/inets/doc/src/tftp.xml deleted file mode 100644 index 10398f5088..0000000000 --- a/lib/inets/doc/src/tftp.xml +++ /dev/null @@ -1,647 +0,0 @@ -<?xml version="1.0" encoding="utf-8" ?> -<!DOCTYPE erlref SYSTEM "erlref.dtd"> - -<erlref> - <header> - <copyright> - <year>2006</year><year>2015</year> - <holder>Ericsson AB. All Rights Reserved.</holder> - </copyright> - <legalnotice> - 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. - - </legalnotice> - - <title>tftp</title> - <prepared></prepared> - <docno></docno> - <date></date> - <rev></rev> - </header> - <module>tftp</module> - <modulesummary>Trivial FTP.</modulesummary> - <description> - <p>This is a complete implementation of the following IETF standards:</p> - <list type="bulleted"> - <item>RFC 1350, The TFTP Protocol (revision 2)</item> - <item>RFC 2347, TFTP Option Extension</item> - <item>RFC 2348, TFTP Blocksize Option</item> - <item>RFC 2349, TFTP Timeout Interval and Transfer Size Options</item> - </list> - <p>The only feature that not is implemented is - the "netascii" transfer mode.</p> - <p>The <seealso marker="#start/1">start/1</seealso> function starts - a daemon process listening for UDP packets on a port. When it - receives a request for read or write, it spawns a temporary server - process handling the transfer.</p> - <p>On the client side, - function <seealso marker="#read_file/3">read_file/3</seealso> - and <seealso marker="#write_file/3">write_file/3</seealso> - spawn a temporary client process establishing - contact with a TFTP daemon and perform the file transfer.</p> - <p><c>tftp</c> uses a callback module to handle the file - transfer. Two such callback modules are provided, - <c>tftp_binary</c> and <c>tftp_file</c>. See - <seealso marker="#read_file/3">read_file/3</seealso> and - <seealso marker="#write_file/3">write_file/3</seealso> for details. - You can also implement your own callback modules, see - <seealso marker="#tftp_callback">CALLBACK FUNCTIONS</seealso>. - A callback module provided by - the user is registered using option <c>callback</c>, see - <seealso marker="#options">DATA TYPES</seealso>.</p> - </description> - - <section> - <title>TFTP SERVER SERVICE START/STOP</title> - - <p>A TFTP server can be configured to start statically when starting - the <c>Inets</c> application. Alternatively, it can be started dynamically - (when <c>Inets</c> is already started) by calling the <c>Inets</c> application - API <c>inets:start(tftpd, ServiceConfig)</c> or - <c>inets:start(tftpd, ServiceConfig, How)</c>, - see <seealso marker="inets">inets(3)</seealso> for details. - The <c>ServiceConfig</c> for TFTP is described in - the <seealso marker="#options">DATA TYPES</seealso> - section.</p> - - <p>The TFTP server can be stopped using <c>inets:stop(tftpd, Pid)</c>, - see <seealso marker="inets">inets(3)</seealso> for details.</p> - - <p>The TPFT client is of such a temporary nature that it is not - handled as a service in the <c>Inets</c> service framework.</p> - - </section> - - <section> - <marker id="options"></marker> - <title>DATA TYPES</title> - <p><c>ServiceConfig = Options</c></p> - <p><c>Options = [option()]</c></p> - <p>Most of the options are common for both the client and the server - side, but some of them differs a little. - The available <c>option()</c>s are as follows:</p> - <taglist> - <tag><c>{debug, Level}</c></tag> - <item> - <p><c>Level = none | error | warning | brief | normal | verbose | all</c></p> - <p>Controls the level of debug printouts. - Default is <c>none</c>.</p> - </item> - <tag><c>{host, Host}</c></tag> - <item> - <p><c>Host = hostname()</c>, see - <seealso marker="kernel:inet">inet(3)</seealso>.</p> - <p>The name or IP address of the host where the TFTP daemon - resides. This option is only used by the client.</p> - </item> - <tag><c>{port, Port}</c></tag> - <item> - <p><c>Port = int()</c></p> - <p>The TFTP port where the daemon listens. Defaults is - the standardized number 69. On the server side, it can - sometimes make sense to set it to 0, meaning that - the daemon just picks a free port (which one is - returned by function <c>info/1</c>).</p> - <p>If a socket is connected already, option - <c>{udp, [{fd, integer()}]}</c> can be used to pass the - open file descriptor to <c>gen_udp</c>. This can be automated - by using a command-line argument stating the - prebound file descriptor number. For example, if the - port is 69 and file descriptor 22 is opened by - <c>setuid_socket_wrap</c>, the command-line argument - "-tftpd_69 22" triggers the prebound file - descriptor 22 to be used instead of opening port 69. - The UDP option <c>{udp, [{fd, 22}]}</c> is automatically added. - See <c>init:get_argument/</c> about command-line arguments and - <c>gen_udp:open/2</c> about UDP options.</p> - </item> - <tag><c>{port_policy, Policy}</c></tag> - <item> - <p><c>Policy = random | Port | {range, MinPort, MaxPort}</c></p> - <p><c>Port = MinPort = MaxPort = int()</c></p> - <p>Policy for the selection of the temporary port that is used - by the server/client during the file transfer. Default is - <c>random</c>, which is the standardized policy. With this - policy a randomized free port is used. A single port or a range - of ports can be useful if the protocol passes through a - firewall.</p> - </item> - <tag><c>{udp, Options}</c></tag> - <item> - <p><c>Options = [Opt]</c>, see - <seealso marker="kernel:gen_udp#open/1">gen_udp:open/2</seealso>.</p> - </item> - <tag><c>{use_tsize, Bool}</c></tag> - <item> - <p><c>Bool = bool()</c></p> - <p>Flag for automated use of option <c>tsize</c>. With - this set to <c>true</c>, the <c>write_file/3</c> client - determines the filesize and sends it to the server as - the standardized <c>tsize</c> option. A <c>read_file/3</c> - client acquires only a filesize from the server by sending - a zero <c>tsize</c>.</p> - </item> - <tag><c>{max_tsize, MaxTsize}</c></tag> - <item> - <p><c>MaxTsize = int() | infinity</c></p> - <p>Threshold for the maximal filesize in bytes. The transfer - is aborted if the limit is exceeded. - Default is <c>infinity</c>.</p> - </item> - <tag><c>{max_conn, MaxConn}</c></tag> - <item> - <p><c>MaxConn = int() | infinity</c></p> - <p>Threshold for the maximal number of active connections. - The daemon rejects the setup of new connections if - the limit is exceeded. Default is <c>infinity</c>.</p> - </item> - <tag><c>{TftpKey, TftpVal}</c></tag> - <item> - <p><c>TftpKey = string()</c> <br></br> -<c>TftpVal = string()</c></p> - <p>Name and value of a TFTP option.</p> - </item> - <tag><c>{reject, Feature}</c></tag> - <item> - <p><c>Feature = Mode | TftpKey</c> <br></br> -<c> Mode = read | write</c> <br></br> -<c> TftpKey = string()</c></p> - <p>Controls which features to reject. This is - mostly useful for the server as it can restrict the use - of certain TFTP options or read/write access.</p> - </item> - <tag><c>{callback, {RegExp, Module, State}}</c></tag> - <item> - <p><c>RegExp = string()</c> <br></br> -<c>Module = atom()</c> <br></br> -<c>State = term()</c></p> - <p>Registration of a callback module. When a file is to be - transferred, its local filename is matched to the regular - expressions of the registered callbacks. The first matching - callback is used during the transfer. See - <seealso marker="#read_file/3">read_file/3</seealso> and - <seealso marker="#write_file/3">write_file/3</seealso>. - </p> - <p>The callback module must implement the <c>tftp</c> behavior, see - <seealso marker="#tftp_callback">CALLBACK FUNCTIONS</seealso>.</p> - </item> - - <tag><c>{logger, Module}</c></tag> - <item> - <p><c>Module = module()()</c></p> - - <p>Callback module for customized logging of errors, warnings, and - info messages. The callback module must implement the - <c>tftp_logger</c> behavior, see - <seealso marker="#tftp_logger">LOGGER FUNCTIONS</seealso>. - The default module is <c>tftp_logger</c>.</p> - </item> - - <tag><c>{max_retries, MaxRetries}</c></tag> - <item> - <p><c>MaxRetries = int()</c></p> - - <p>Threshold for the maximal number of retries. By default - the server/client tries to resend a message up to - five times when the time-out expires.</p> - </item> - </taglist> - </section> - - <funcs> - <func> - <name>change_config(daemons, Options) -> [{Pid, Result}]</name> - <fsummary>Changes configuration for all daemons. - </fsummary> - <type> - <v>Options = [option()]</v> - <v>Pid = pid()</v> - <v>Result = ok | {error, Reason}</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Changes configuration for all TFTP daemon processes. </p> - </desc> - </func> - - <func> - <name>change_config(servers, Options) -> [{Pid, Result}]</name> - <fsummary>Changes configuration for all servers. - </fsummary> - <type> - <v>Options = [option()]</v> - <v>Pid = pid()</v> - <v>Result = ok | {error, Reason}</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Changes configuration for all TFTP server processes.</p> - </desc> - </func> - - <func> - <name>change_config(Pid, Options) -> Result</name> - <fsummary>Changes configuration for a TFTP daemon, server, - or client process.</fsummary> - <type> - <v>Pid = pid()</v> - <v>Options = [option()]</v> - <v>Result = ok | {error, Reason}</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Changes configuration for a TFTP daemon, server, or client process.</p> - </desc> - </func> - - <func> - <name>info(daemons) -> [{Pid, Options}]</name> - <fsummary>Returns information about all daemons.</fsummary> - <type> - <v>Pid = [pid()()]</v> - <v>Options = [option()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Returns information about all TFTP daemon processes.</p> - </desc> - </func> - - <func> - <name>info(servers) -> [{Pid, Options}]</name> - <fsummary>Returns information about all servers.</fsummary> - <type> - <v>Pid = [pid()()]</v> - <v>Options = [option()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Returns information about all TFTP server processes. </p> - </desc> - </func> - - <func> - <name>info(Pid) -> {ok, Options} | {error, Reason}</name> - <fsummary>Returns information about a daemon, server, or client process.</fsummary> - <type> - <v>Options = [option()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Returns information about a TFTP daemon, server, or client process.</p> - </desc> - </func> - - <func> - <name>read_file(RemoteFilename, LocalFilename, Options) -> {ok, LastCallbackState} | {error, Reason}</name> - <fsummary>Reads a (virtual) file from a TFTP server.</fsummary> - <type> - <v>RemoteFilename = string()</v> - <v>LocalFilename = binary | string()</v> - <v>Options = [option()]</v> - <v>LastCallbackState = term()</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Reads a (virtual) file <c>RemoteFilename</c> from a TFTP - server.</p> - <p>If <c>LocalFilename</c> is the atom <c>binary</c>, - <c>tftp_binary</c> is used as callback module. It concatenates - all transferred blocks and returns them as one single binary - in <c>LastCallbackState</c>.</p> - <p>If <c>LocalFilename</c> is a string and there are no - registered callback modules, <c>tftp_file</c> is used as - callback module. It writes each transferred block to the file - named <c>LocalFilename</c> and returns the number of - transferred bytes in <c>LastCallbackState</c>.</p> - <p>If <c>LocalFilename</c> is a string and there are registered - callback modules, <c>LocalFilename</c> is tested against - the regexps of these and the callback module corresponding to - the first match is used, or an error tuple is returned if no - matching regexp is found.</p> - </desc> - </func> - - <func> - <name>start(Options) -> {ok, Pid} | {error, Reason}</name> - <fsummary>Starts a daemon process.</fsummary> - <type> - <v>Options = [option()]</v> - <v>Pid = pid()</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Starts a daemon process listening for UDP packets on a - port. When it receives a request for read or write, it spawns - a temporary server process handling the actual transfer - of the (virtual) file.</p> - </desc> - </func> - - <func> - <name>write_file(RemoteFilename, LocalFilename, Options) -> {ok, LastCallbackState} | {error, Reason}</name> - <fsummary>Writes a (virtual) file to a TFTP server.</fsummary> - <type> - <v>RemoteFilename = string()</v> - <v>LocalFilename = binary() | string()</v> - <v>Options = [option()]</v> - <v>LastCallbackState = term()</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Writes a (virtual) file <c>RemoteFilename</c> to a TFTP - server.</p> - <p>If <c>LocalFilename</c> is a binary, <c>tftp_binary</c> is - used as callback module. The binary is transferred block by - block and the number of transferred bytes is returned in - <c>LastCallbackState</c>.</p> - <p>If <c>LocalFilename</c> is a string and there are no - registered callback modules, <c>tftp_file</c> is used as - callback module. It reads the file named <c>LocalFilename</c> - block by block and returns the number of transferred bytes - in <c>LastCallbackState</c>.</p> - <p>If <c>LocalFilename</c> is a string and there are registered - callback modules, <c>LocalFilename</c> is tested against - the regexps of these and the callback module corresponding to - the first match is used, or an error tuple is returned if no - matching regexp is found.</p> - </desc> - </func> - </funcs> - - <section> - <marker id="tftp_callback"></marker> - <title>CALLBACK FUNCTIONS</title> - <p>A <c>tftp</c> callback module is to be implemented as a - <c>tftp</c> behavior and export the functions listed - in the following.</p> - <p>On the server side, the callback interaction starts with a call to - <c>open/5</c> with the registered initial callback state. - <c>open/5</c> is expected to open the (virtual) file. Then either - function <c>read/1</c> or <c>write/2</c> is invoked - repeatedly, once per transferred block. At each function call, - the state returned from the previous call is obtained. When - the last block is encountered, function <c>read/1</c> or - <c>write/2</c> is expected to close the (virtual) file - and return its last state. Function <c>abort/3</c> is only - used in error situations. Function <c>prepare/5</c> is not used on - the server side.</p> - <p>On the client side, the callback interaction is the same, but it - starts and ends a bit differently. It starts with a call to - <c>prepare/5</c> with the same arguments as <c>open/5</c> takes. - <c>prepare/5</c> is expected to validate the TFTP options - suggested by the user and to return the subset of them that it - accepts. Then the options are sent to the server, which performs - the same TFTP option negotiation procedure. The options that are - accepted by the server are forwarded to function <c>open/5</c> - on the client side. On the client side, function <c>open/5</c> - must accept all option as-is or reject the transfer. Then - the callback interaction follows the same pattern as described - for the server side. When the last block is encountered in - <c>read/1</c> or <c>write/2</c>, the returned state is forwarded to - the user and returned from <c>read_file</c>/3 or - <c>write_file/3</c>.</p> - - <p> If a callback (performing the file access - in the TFTP server) takes too long time (more than - the double TFTP time-out), the server aborts the - connection and sends an error reply to the client. - This implies that the server releases resources - attached to the connection faster than before. The - server simply assumes that the client has given - up.</p> - - <p>If the TFTP server receives yet another request from - the same client (same host and port) while it - already has an active connection to the client, it - ignores the new request if the request is - equal to the first one (same filename and options). - This implies that the (new) client will be served - by the already ongoing connection on the server - side. By not setting up yet another connection, in - parallel with the ongoing one, the server - consumes less resources.</p> - - <marker id="prepare"></marker> - </section> - - <funcs> - <func> - <name>Module:abort(Code, Text, State) -> ok</name> - <fsummary>Aborts the file transfer.</fsummary> - <type> - <v>Code = undef | enoent | eacces | enospc</v> - <v> | badop | eexist | baduser | badopt</v> - <v> | int()</v> - <v>Text = string()</v> - <v>State = term()</v> - </type> - <desc> - <p>Invoked when the file transfer is aborted.</p> - <p>The callback function is expected to clean - up its used resources after the aborted file - transfer, such as closing open file - descriptors and so on. The function is not - invoked if any of the other callback - functions returns an error, as it is - expected that they already have cleaned up - the necessary resources. However, it is - invoked if the functions fail (crash).</p> - </desc> - </func> - - <func> - <name>Module:open(Peer, Access, Filename, Mode, SuggestedOptions, State) -> {ok, AcceptedOptions, NewState} | {error, {Code, Text}}</name> - <fsummary>Opens a file for read or write access.</fsummary> - <type> - <v>Peer = {PeerType, PeerHost, PeerPort}</v> - <v>PeerType = inet | inet6</v> - <v>PeerHost = ip_address()</v> - <v>PeerPort = integer()</v> - <v>Access = read | write</v> - <v>Filename = string()</v> - <v>Mode = string()</v> - <v>SuggestedOptions = AcceptedOptions = [{Key, Value}]</v> - <v> Key = Value = string()</v> - <v>State = InitialState | term()</v> - <v> InitialState = [] | [{root_dir, string()}]</v> - <v>NewState = term()</v> - <v>Code = undef | enoent | eacces | enospc</v> - <v> | badop | eexist | baduser | badopt</v> - <v> | int()</v> - <v>Text = string()</v> - </type> - <desc> - <p>Opens a file for read or write access.</p> - <p>On the client side, where the <c>open/5</c> call has been - preceded by a call to <c>prepare/5</c>, all options must be - accepted or rejected.</p> - <p>On the server side, where there is no preceding - <c>prepare/5</c> call, no new options can be added, but - those present in <c>SuggestedOptions</c> can be - omitted or replaced with new values in <c>AcceptedOptions</c>.</p> - - <marker id="read"></marker> - </desc> - </func> - - <func> - <name>Module:prepare(Peer, Access, Filename, Mode, SuggestedOptions, InitialState) -> {ok, AcceptedOptions, NewState} | {error, {Code, Text}}</name> - <fsummary>Prepares to open a file on the client side.</fsummary> - <type> - <v>Peer = {PeerType, PeerHost, PeerPort}</v> - <v>PeerType = inet | inet6</v> - <v>PeerHost = ip_address()</v> - <v>PeerPort = integer()</v> - <v>Access = read | write</v> - <v>Filename = string()</v> - <v>Mode = string()</v> - <v>SuggestedOptions = AcceptedOptions = [{Key, Value}]</v> - <v> Key = Value = string()</v> - <v>InitialState = [] | [{root_dir, string()}]</v> - <v>NewState = term()</v> - <v>Code = undef | enoent | eacces | enospc</v> - <v> | badop | eexist | baduser | badopt</v> - <v> | int()</v> - <v>Text = string()</v> - </type> - <desc> - <p>Prepares to open a file on the client side.</p> - <p>No new options can be added, but those present in - <c>SuggestedOptions</c> can be omitted or replaced with new - values in <c>AcceptedOptions</c>.</p> - <p>This is followed by a call to <c>open/4</c> before any - read/write access is performed. <c>AcceptedOptions</c> is - sent to the server, which replies with the options that it - accepts. These are then forwarded to <c>open/4</c> as - <c>SuggestedOptions</c>.</p> - - <marker id="open"></marker> - </desc> - </func> - - <func> - <name>Module:read(State) -> {more, Bin, NewState} | {last, Bin, FileSize} | {error, {Code, Text}}</name> - <fsummary>Reads a chunk from the file.</fsummary> - <type> - <v>State = NewState = term()</v> - <v>Bin = binary()</v> - <v>FileSize = int()</v> - <v>Code = undef | enoent | eacces | enospc</v> - <v> | badop | eexist | baduser | badopt</v> - <v> | int()</v> - <v>Text = string()</v> - </type> - <desc> - <p>Reads a chunk from the file.</p> - <p>The callback function is expected to close - the file when the last file chunk is - encountered. When an error is encountered, - the callback function is expected to clean - up after the aborted file transfer, such as - closing open file descriptors, and so on. In both - cases there will be no more calls to any of - the callback functions.</p> - - <marker id="write"></marker> - </desc> - </func> - - <func> - <name>Module:write(Bin, State) -> {more, NewState} | {last, FileSize} | {error, {Code, Text}}</name> - <fsummary>Writes a chunk to the file.</fsummary> - <type> - <v>Bin = binary()</v> - <v>State = NewState = term()</v> - <v>FileSize = int()</v> - <v>Code = undef | enoent | eacces | enospc</v> - <v> | badop | eexist | baduser | badopt</v> - <v> | int()</v> - <v>Text = string()</v> - </type> - <desc> - <p>Writes a chunk to the file.</p> - <p>The callback function is expected to close - the file when the last file chunk is - encountered. When an error is encountered, - the callback function is expected to clean - up after the aborted file transfer, such as - closing open file descriptors, and so on. In both - cases there will be no more calls to any of - the callback functions.</p> - - <marker id="abort"></marker> - </desc> - </func> - </funcs> - - <section> - <marker id="tftp_logger"></marker> - <title>LOGGER FUNCTIONS</title> - - <p>A <c>tftp_logger</c> callback module is to be implemented as a - <c>tftp_logger</c> behavior and export the following functions:</p> - - <marker id="error_msg"></marker> - </section> - - <funcs> - <func> - <name>Logger:error_msg(Format, Data) -> ok | exit(Reason)</name> - <fsummary>Logs an error message.</fsummary> - <type> - <v>Format = string()</v> - <v>Data = [term()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Logs an error message. - See <c>error_logger:error_msg/2</c> for details.</p> - - <marker id="warning_msg"></marker> - </desc> - </func> - - <func> - <name>Logger:info_msg(Format, Data) -> ok | exit(Reason)</name> - <fsummary>Logs an info message.</fsummary> - <type> - <v>Format = string()</v> - <v>Data = [term()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Logs an info message. - See <c>error_logger:info_msg/2</c> for details.</p> - </desc> - </func> - - <func> - <name>Logger:warning_msg(Format, Data) -> ok | exit(Reason)</name> - <fsummary>Logs a warning message.</fsummary> - <type> - <v>Format = string()</v> - <v>Data = [term()]</v> - <v>Reason = term()</v> - </type> - <desc> - <p>Logs a warning message. - See <c>error_logger:warning_msg/2</c> for details.</p> - - <marker id="info_msg"></marker> - </desc> - </func> - </funcs> -</erlref> - - |