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finish reqheader() function
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@petercorke
petercorke committed Sep 17, 2018
1 parent 45d45a2 commit 23a0f10
Showing 1 changed file with 144 additions and 19 deletions.
163 changes: 144 additions & 19 deletions stl/webserver.m
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Original file line number Diff line number Diff line change
@@ -1,20 +1,66 @@
classdef webserver < handle %#codegen
%webserver Lightweight webserver library
%
% This class contains methods that implement a lightweight webserver
% for MATLAB Coder.
%
% Methods::
% webserver create a webserver instance
% debug enable debugging messages
% details display HTTP header
%-
% html send string to browser
% template send file with substitutions to browser
% file send file to browser
% data send data to browser
% error send error code to browser
%-
% url URL for current request
% isGET test for GET request
% isPOST test for POST request
% reqheader get element of HTTP header
% getarg get element of HTTP GET header
% postarg get element of HTTP POST header
%
% Copyright (C) 2018, by Peter I. Corke

methods(Static)

function obj = webserver(port, callback)
function obj = webserver(port, callback, arg)
%webserver Create a webserver
%
% webserver(port, callback) creates a new webserver executing it a separate
% thread and listening on the specified port (int). The MATLAB entrypoint
% named callback is invoked on every GET and PUT request to the server.

% webserver Create a web server instance
port = int32(port);
coder.cinclude('httpd.h');
coder.ceval('web_start', port, cstring(callback));
coder.cinclude('stl.h');
if nargin == 3
coder.ceval('web_start', port, cstring(callback), coder.ref(arg));
else
coder.ceval('web_start', port, cstring(callback), coder.opaque('void *', 'NULL'));
end

end

function debug(d)
%webserver.debug Control debugging
%
% webserver.debug(D) controls the display of debug messages. If D is true messages
% are enabled.
%
% See also: stl.log.
coder.cinclude('httpd.h');
coder.ceval('web_debug', d);
end

function u = url()
%webserver.url Get the URL for the request
%
% url = webserver.url() is a character array representing the URL associated with
% this request.
coder.cinclude('httpd.h');

u = '';
Expand All @@ -34,23 +80,48 @@ function debug(d)
end

function details()
%webserver.details Show HTTP header details
%
% webserver.details() displays the HTTP header via the logging channel.
%
% See also: stl.log.

coder.ceval('web_show_request_header');
end

function error(errno, msg)
%webserver.error Send error code to browser
%
% websever.error(code, msg) send an error code (eg. 404) and message to the
% requesting browser.
coder.ceval('web_error', errno, cstring(s));
end

function html(s)
% webserver.html Send an HTML string to browser
%webserver.html Send an HTML string to browser
%
% weserver.html(str) the string str is sent to the requesting browser. The string
% can be plain text or HTML.
%
% See also: webserver.template, webserver.error.

coder.ceval('web_html', cstring(s));
end

function template(filename, values)
% webserver.template Send template file with substitution to browser
%webserver.template Send template file with substitution to browser
%
% webserver.template(filename, values) sends the contents of the specified file
% to the requesting browser with substitutions. Elements of the struct values
% are substituted for special HTML tags.
%
% For example the value of values.a is substitued by:
% <TMPL_VAR name="a">
%
% See also: webserver.html, webserver.error, CTemplate.

coder.cinclude('httpd.h');


if nargin == 2
if ~isa(values, 'struct')
Expand All @@ -64,38 +135,71 @@ function template(filename, values)
if size(v,1) > 1
fprintf('numeric value must be scalar or row vector');
else
coder.ceval('web_setvalue', cstring(name), cstring(num2str(v)));
if isinteger(v)
fmt = '%d';
else
fmt = '%g';
end
coder.ceval('web_setvalue', cstring(name), cstring(sprintf(fmt, v)));
end
end
end
coder.ceval('web_template', cstring(filename));
end

function file(filename, type)
% webserver.file Send file and content type to browser
%webserver.file Send file and content type to browser
%
% webserver.file(filename, type) send the specified file to the requesting browser, with
% the specified MIME type.
%
% See also: webserver.template, webserver.html, webserver.error.

coder.ceval('web_file', cstring(filename), cstring(type));
end

function data(s, type)
% webserver.file Send data and content type to browser
%webserver.file Send data and content type to browser
%
% webserver.data(data, type) send the character array data to the requesting browser, with
% the specified MIME type.
%
% Notes::
% - The data could be a binary string, eg. an image.
%
% See also: webserver.template, webserver.html, webserver.error.
coder.ceval('web_data', s, length(s), cstring(type));
end

function v = isPOST()
% webserver.ispost Test if POST request
%webserver.isPOST Test for POST request
%
% v = webserver.isPOST() is true if this request is an HTTP POST.
%
% See also: webserver.isGET.
v = int32(0);
v = coder.ceval('web_isPOST');
end

function v = isGET()
% webserver.isget Test if GET request
% webserver.isGET Test for GET request
%
% v = webserver.isGET() is true if this request is an HTTP GET.
%
% See also: webserver.isPOST.
v = int32(0);
v = coder.ceval('web_isPOST');
v = ~v; % codegen can't do this in the one line...
v = ~v; % codegen cant do this in the one line...
end

function s = reqheader(name)
% webserver.reqheader Return value of request header item
%webserver.reqheader Return value of request header item
%
% v = webserver.reqheader(key) is a character array representing the value of
% the specified key in the HTTP request header.
%
% Notes::
% - Returns empty string if the key is not found.
coder.cinclude('httpd.h');
coder.varsize('s');
s = '';
Expand All @@ -104,18 +208,30 @@ function data(s, type)
buf = char(zeros(1,BUFSIZ)); % create a buffer to write into, all nulls

% content
% coder.ceval('web_url', coder.wref(buf), BUFSIZ); % evaluate the C function

for i=1:BUFSIZ-1 % find the end of the string, where the first unwritten null is
if buf(i) == 0
s = buf(1:i-1); % found a null, return variable length array up to here
return;
found = int32(0);
found = coder.ceval('web_reqheader', coder.wref(buf), BUFSIZ); % evaluate the C function

if found
for i=1:BUFSIZ-1 % find the end of the string, where the first unwritten null is
if buf(i) == 0
s = buf(1:i-1); % found a null, return variable length array up to here
return;
end
end
end
end

function s = getarg(name)
% webserver.getarg Return value of GET argument
%webserver.getarg Return value of GET argument
%
% v = webserver.getarg(key) is a character array representing the value of
% the specified key in the HTTP GET request header.
%
% Notes::
% - These parameters are on the end of the URL, eg. ?key1=val1&key2=val2
% - Returns empty string if the key is not found.
%
% See also: webserver.isGET, webserver.url.

coder.cinclude('httpd.h');
coder.varsize('s');
Expand All @@ -138,7 +254,16 @@ function data(s, type)
end

function s = postarg(name)
% webserver.postarg Return value of POST argument
%webserver.postarg Return value of POST argument
%
% v = webserver.postarg(key) is a character array representing the value of
% the specified key in the HTTP POST request header.
%
% Notes::
% - POST data is typically sent from the browser using <form> and <input> tags.
% - Returns empty string if the key is not found.
%
% See also: webserver.isPOST, webserver.url.
coder.cinclude('httpd.h');
coder.varsize('s');
s = '';
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