Retrieving Mac OS X Proxy IP address - c

I'm trying to programmatically get the proxy IP address or URL set on a system.
I found code that might work in a previous question here, but it's in Objective-C and what I am trying to use is plain C.
I've tried translating that obj-c code to C but no success.
Anyone knows how to get the system proxy in C?
Thank you

This is a C translation of that answer:
CFDictionaryRef proxies = SCDynamicStoreCopyProxies(NULL);
if (proxies) {
CFStringRef pacURL = (CFStringRef)CFDictionaryGetValue(proxies,
kSCPropNetProxiesProxyAutoConfigURLString);
if (pacURL) {
char url[257] = {};
CFStringGetCString(pacURL, url, sizeof url, kCFStringEncodingASCII);
// do something with url
}
CFRelease(proxies);
}
It needs to be linked to two frameworks: SystemConfiguration and CoreFoundation.
Note that this code gets the URL for automatic proxy configuration (kSCPropNetProxiesProxyAutoConfigURLString), if any. There are several other possible proxies, e.g. HTTP proxy or HTTPS proxy. For a list of all possible proxies, see the SCSchemaDefinitions Reference.

Related

Google App Engine Channel API with custom domains

In my GAE app (Python) I have implemented multitenancy and multi-site support based on the host part of the request object.
For example, www.foo.com/index.html and www.bar.com/index.html are both handled by the same app (e.g. myapp.appspot.com). The app reads the host-value and then decides which namespace and site-configuration to use. This works great as long as the app receives the request directly from the user-agent.
However, I would like to use the Channel API, but there is an issue because requests to /_ah/channel/connected/ and /_ah/channel/disconnected/ are not originating from the original user-agent. Instead, the request has Host: myapp.appspot.com and the parameter to=myapp.appspot.com. (The from parameter is the token I expect. Also www.foo.com/_ah/channel/jsapi is redirected to a talkgadget server which is not documented but seems to be as expected.)
I assume, the problem is caused by the code in channel.js which doesn't call my app using the original host, e.g. www.foo.com/_ah/channel/connected. Instead it uses a talkgadget.google.com host which (as far as I can tell) will then call my app, but using myapp.appspot.com, ignoring the original host and so I cannot use the request's host value for my purpose.
As a workaround, I can figure out a way of including the host information into the channel token, so when my connected and disconnected handlers receive the token, they can use the token instead.
However, I would like to know if there is a better approach, where I could still get the original host name (e.g. www.foo.com) requests to /_ah/channel/connected/ and /_ah/channel/disconnected/. Any ideas?
This is what I have tried so far (with-out any success):
Adding the custom domain host name to the JS src attribute:
<script type="text/javascript" src="//www.foo.com/_ah/channel/jsapi"></script>
I also tried to manually override the base-url of the channel socket, suggested here: https://stackoverflow.com/questions/16558776/google-app-engine-channel-api-same-origin-policy
<script type="text/javascript">
onOpened = function() {
// TODO
};
onMessage = function() {
// TODO
};
onError = function() {
// TODO
};
onClose = function() {
// TODO
};
goog.appengine.Socket.BASE_URL = "https://www.foo.com/_ah/channel/";
channel = new goog.appengine.Channel('{{channelToken}}');
socket = channel.open();
socket.onopen = onOpened;
socket.onmessage = onMessage;
socket.onerror = onError;
socket.onclose = onClose;
</script>
I couldn't find any official documentation for channel.js and I don't want to implement something that is going to break easily with the next update by Google.
Short of a proxy, I don't see a better way than including the information in-band. The problem is that the library/infrastructure (can't be certain without looking deeper) is stripping the HTTP-layer information (the Host header), and indeed you don't have any control of the HTTP layer to pass custom headers, etc. So, you either need to have the info at a lower layer (TCP doesn't even provide a means to do this, and since the entrypoint of your code is through the browser running channel.js, rather than a system-level process running on the bare network interface, this is out of the picture decisively), or at a higher layer, ie. within the channel.

Apache filter request hostname comparison does not work

I'm new to writing apache output filters and even more to writing them in c. I've taken a sample filter (mod_substitute) source and am trying to make it work only if the request is for a specific host. I need to make this a programatic feature and not configuration wise for my own reasons.
I am using the following code to try this:
request_rec *req = f->r;
ngf_module_ctx *ctx = f->ctx;
/* Test to see if this is a domain that needs optimization */
if (req->hostname != "localhost") {
ap_pass_brigade(f->next, bb);
return APR_SUCCESS;
}
using debug printing I saw that the req->hostname value does show up as localhost, however the comparison itself fails.
what am I doing wrong ?
You're using a pointer equality operator (!=) to compare strings. This is C, remember -- you have to use a function like strcmp to compare strings.
If you haven't worked in C before, writing an Apache module is probably not a great place to start. Back up and get familiar with the language first.

Flex mobile request to time.nist.gov

How do I access the time provided by internet time services like time.nist.gov from within my Flex mobile application?
Is there a way to do this via URLRequest or HTTPService?
Alright, here is the call to the Yahoo WebServices with a simple HTTPService;
<s:HTTPService id="serverTime" url="http://developer.yahooapis.com/TimeService/V1/getTime?appid=myID" result="resultHandler(event)" resultFormat="e4x"/>
In my resultHandler, the trace on Timestamp already fails (returns no value);
private function resultHandler(event:ResultEvent):void {
// this works (outputs the xml as shown on Yahoo
trace(event.result);
var xmlResult:XML = event.result as XML;
var timestamp:String = xmlResult.Timestamp;
trace("stamp" + timestamp);
}
time.nist.gov (or any other time server) use NTP protocol for communication, not HTTP, so you can't use URLRequest or HTTPService.
I don't know of any NTP client implementation in ActionScript. You may need to do your own.
Depending on your needs, you may use a webservice that provides "pretty accurate" time, like Yahoo WebServices. This goes over HTTP, so you can use URLRequest or HTTPService in Flex.

Setting the header to be content image in CakePHP

I am writing an action in a controller where in a certain case, I want to output raw image data directly, and want to set the header content-type appropriate. However I think the header is already being set earlier by CakePHP (I am setting render to be false).
Is there a way to get around this? Thanks!
As said before, CakePHP does not send headers when render is false. Beware though, that any code doing an 'echo' will send headers (except you are using output-buffering). This includes messages from PHP (warnings etc.).
Sending the file can be done in numerous ways, but there are two basic ways:
Send the file using plain PHP
function send_file_using_plain_php($filename) {
// Avoids hard to understand error-messages
if (!file_exists($filename)) {
throw RuntimeException("File $filename not found");
}
$fileinfo = new finfo(FILEINFO_MIME);
$mime_type = $fileinfo->file($filename);
// The function above also returns the charset, if you don't want that:
$mime_type = reset(explode(";", $mime_type));
// gets last element of an array
header("Content-Type: $mime_type");
header("Content-Length: ".filesize($filename));
readfile($filename);
}
Use X-Sendfile and have the Webserver serve the file
// This was only tested with nginx
function send_file_using_x_sendfile($filename) {
// Avoids hard to understand error-messages
if (!file_exists($filename)) {
throw RuntimeException("File $filename not found");
}
$fileinfo = new finfo(FILEINFO_MIME);
$mime_type = $fileinfo->file($filename);
// The function above also returns the charset, if you don't want that:
$mime_type = reset(explode(";", $mime_type));
// gets last element of an array
header("Content-Type: $mime_type");
// The slash makes it absolute (to the document root of your server)
// For apache and lighttp use:
header("X-Sendfile: /$filename");
// or for nginx: header("X-Accel-Redirect: /$filename");
}
The first function occupies one PHP-process / thread while the data is being send and supports no Range-Requests or other advanced HTTP-features. This should therefore only be used with small files, or on very small sites.
Using X-Sendfile you get all that, but you need to know which webserver is running and maybe even a change to the configuration is needed. Especially when using lighttp or nginx this really pays off performance-wise, because these webservers are extremly good at serving static files from disk.
Both functions support files not in the document-root of the webserver. In nginx there are so called "internal locations" (http://wiki.nginx.org/HttpCoreModule#internal). These can be used with the X-Accel-Redirect-Header. Even rate-throtteling is possible, have a look at http://wiki.nginx.org/XSendfile.
If you use apache, there is mod_xsendfile, which implements the feature needed by the second function.
It's not $this->render(false), it's $this->autoRender=false; The header is not sent in the controller action unless you echo something out.
If render is false, cake will not send a header.
You can rely on plain ol' php here.
PNG:
header('Content-Type: image/gif');
readfile('path/to/myimage.gif');
JPEG:
header('Content-Type: image/jpeg');
readfile('path/to/myimage.jpg');
PNG:
header('Content-Type: image/png');
readfile('path/to/myimage.png');

How can I upload a file to a Sharepoint Document Library using Silverlight and client web-services?

Most of the solutions I've come across for Sharepoint doc library uploads use the HTTP "PUT" method, but I'm having trouble finding a way to do this in Silverlight because it has restrictions on the HTTP Methods. I visited this http://msdn.microsoft.com/en-us/library/dd920295(VS.95).aspx to see how to allow PUT in my code, but I can't find how that helps you use an HTTP "PUT".
I am using client web-services, so that limits some of the Sharepoint functions available.
That leaves me with these questions:
Can I do an http PUT in Silverlight?
If I can't or there is another better way to upload a file, what is it?
Thanks
Figured it out!! works like a charm
public void UploadFile(String fileName, byte[] file)
{
// format the destination URL
string[] destinationUrls = {"http://qa.sp.dca/sites/silverlight/Answers/"+fileName};
// fill out the metadata
// remark: don't set the Name field, because this is the name of the document
SharepointCopy.FieldInformation titleInformation = new SharepointCopy.FieldInformation
{DisplayName =fileName,
InternalName =fileName,
Type = SharepointCopy.FieldType.Text,
Value =fileName};
// to specify the content type
SharepointCopy.FieldInformation ctInformation = new SharepointCopy.FieldInformation
{DisplayName ="XML Answer Doc",
InternalName ="ContentType",
Type = SharepointCopy.
FieldType.Text,
Value ="xml"};
SharepointCopy.FieldInformation[] metadata = { titleInformation };
// initialize the web service
SharepointCopy.CopySoapClient copyws = new SharepointCopy.CopySoapClient();
// execute the CopyIntoItems method
copyws.CopyIntoItemsCompleted += copyws_CopyIntoItemsCompleted;
copyws.CopyIntoItemsAsync("http://null", destinationUrls, metadata, file);
}
Many Thanks to Karine Bosch for the solution here: http://social.msdn.microsoft.com/Forums/en/sharepointdevelopment/thread/f135aaa2-3345-483f-ade4-e4fd597d50d4
What type of SharePoint deployment and what version of silverlight? If say it is an intranet deployment you could use UNC paths to access your document library in sharepoint and the savefiledialog/openfiledialog available in Silverlight 3.
http://progproblems.blogspot.com/2009/11/saveread-file-from-silverlight-30-in.html
or
http://www.kirupa.com/blend_silverlight/saving_file_locally_pg1.htm
Silverlight has restrictions on what it can do with local files, though I've read that silverlight 4 has some changes.
http://www.wintellect.com/CS/blogs/jprosise/archive/2009/12/16/silverlight-4-s-new-local-file-system-support.aspx

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