March 2009 - Darwin-dev - lists.apple.com

Code-signing broken?
by Tim Murison 06 Mar '09

06 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thread-index: AcmefSB+h61AOV8hWUKFuBlWddxtOQ== Thread-topic: Code-signing broken? User-agent: Microsoft-Entourage/12.15.0.081119 I've been playing some more with code-signing on OS X, basically trying to learn how it works. I created a copy of the system library libz.1.2.3.dylib and started modifying it with a hex editor. Basically, search/replaced all instances of the string "deflate" with "foo_bar" and saved the result. If I perform an nm command, I can see zlib has functions like "_foo_barCopy" etc... The code-signature still passes. So, my question is WTF? _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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How to build an install cd of the Darwin?
by arielfeinerman＠aol.com 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hello, best regards Ariel _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I wish to make an install cd of the Darwin (command line only) from Apple sources without any changes; I asked some people who took part in the Darwin project, but they left one and can not help; If you have any info or know anyone works in the Darwin now, send me please; This email sent to site_archiver(a)lists.apple.com

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RE: Recommendations on uniquely identifying a system.
by Tom Fortmann 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thread-index: AcmdHfZiVyOlLocOSyu4Cs99XtndBwAsSqxw > It still isn't clear wether you are interested in tracking a very > precise piece of hardware or a very precise registration against a > server (whatever it is, since you didn't tell anything about it). > Unless I'm wrong, these could be very different things. Could you > elaborate? We are trying to track a specific machine. This ID value will be sent in all communications with our back-end server. The requirements are that it should be globally unique and persist across application uninstall/re-installs. I've added a person requirement to not leave any stray files on the system after an uninstall. My solutions is to combine the Mac address and the serial number to create the unique ID. These are the Apple recommended values based on TN1103. If either or both of these are not defined I may factor in the IOPlatformUUID value, and as a last resort will default to generate a UUID. Thanks to everyone for their input. I still haven't found any more information on the IOPlatformUUID value, so I'm going to assume Mac and serial number are still the preferred methods. Tom _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: GCC stack size
by Ryan McGann 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Mar 3, 2009, at 2:00 PM, Brian Mastenbrook wrote: On Mar 3, 2009, at 3:35 PM, Ryan McGann wrote: void foo(int flag) { if (flag) { largeStackUsingFunction(); } else { char buf[1000]; /* ... other code which does not call functions ... */ } } Thanks to all for the help. Ryan _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… We have some sample code that shows that the temporary returned from the function doMath is allocated stack space twice, when it can only be used once. But since the function in our actual production code is pretty complex, it's hard to know hwich problem we are experiencing. However, the above examples are both well documented cases of GCC problems; I actually got the basic ideas for both examples from Linus Torvald's (sometimes long) emails regarding Linux's problems with GCC stack allocation. I've been bitten by this problem in the past as well, especially in functions that look a lot like the examples you've given (where an outer if wraps several complex code blocks). The worst of it is that in this example: Just to let everybody know, I got the library to compile with the Intel icc compiler. It produced a stack in debug builds (-O0) that is 116 bytes, and in release builds (-O3) is 92 bytes. Obviously this is perfect for our x86/x86_64 builds. Our PowerPC customers are unfortunately hosed, as the IBM compiler does not look like it will work in the time that I have to finish this project. For PowerPC we will unfortunately lose some major features, but at least it won't panic. This email sent to site_archiver(a)lists.apple.com

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Re: Samba, network interfaces, launchd, etc.
by James Peach 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=661TI7l5g8L8d9pnY7q2vzrUw63ByvbirQSaseBPYRg=; b=hYG5TtCfO3KSFo4TyIOeQXpl6nbKA80dT+ew15f4XUjRreQG7nHn6bY3idiPqHYFFu B0BdTF3vRNc1daMTq/zE1yRHOwVX5XTbPT8k5BK050ssSztwN3ueNwCR5Oiuq2sjlCWe V34/tLVGEeN5TeTWRGK9Y208xCRfoLanD++rE= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=sGuFTNak/NXv9WDkmupcf4qOAaXjkT+vzrmoz6FVQuHBVsJ5Dd5v2jv5M0aG8DsSiz b4eu1FPNtCJyDj+W7+MBbzuulWFWO02LdzxhmUPUSJRB7UKQBxTP6fv8rW6LRXlnJ2Cx nFcDW3Wfh6/NHkpv9zOrFZqGVtW8VfZbGlmok= 2009/3/4 David Farber <caveat+applelists(a)numenor.com>: > I'd like to make Samba listen on a specific network interface instead of > listening on all interfaces. According to the Samba docs, I need to do > something like this: > > [global] > ; interfaces = vmnet1 > interfaces = 192.168.144.0/24 > bind interfaces only = yes > > But this doesn't work on 10.5.4. > > $ sudo lsof -Pi | grep smbd > smbd 1127 root 19u IPv4 0x5446e64 0t0 TCP *:445 > (LISTEN) > smbd 1127 root 20u IPv4 0x681d66c 0t0 TCP *:139 > (LISTEN) > > Since Samba is under launchd control and the sockets it is listening on are > passed to it, my first question is, should I and can I specify the interface > I want in the smbd.plist? Looking through the launchd docs, I didn't see > anything that looked like it would specify an interface. So maybe > specifying the interface is the responsibility of the daemon. There's no way to specify this in the launchd plist. You could file an enhancement request for launchd. > > If so, then my second question would be if it would be appropriate to file a > radar? IMHO, yes. > > Thanks. > > (The interface I want to listen on is VMWare Fusion network interface that > is bound only to the virtual machine that it is running. In other words, I > want to use Samba to privately share files with a virtual machine that is > running locally. I *don't* want Samba running on my local network.) Try using the "hosts allow" smb.conf parameter, eg. append this to yr /etc/smb.conf: [global] hosts deny = ALL hosts allow = 127.0.0.1 -- James Peach | jorgar(a)gmail.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: confusion about memory fragmentation, vm, and blocks
by Mario Emmenlauer 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Thunderbird 2.0.0.18 (Macintosh/20081105) Hi, Can I read up details about that pre-allocated space? Is there a good tutorial or technote? I understand it is quite a lot VM that my application consumes upon startup, about 1GB. It seems a fair amount given that I do 3D rendering and whatnot, but I would still be curious to reduce it. (I've asked about that in a separate thread (Why is virtual memory so high? (crash)) a while ago, but have not yet found a definitive conclusion. Try reading up on virtual memory in general - many of the VM principles used by Mach aren't Mach-specific. Also, take a look at Thats what I have done so far, with the funny result that I now know a lot about abstract VM basics, but completely fail when it comes to practical issues:-( One issue, I have read often that there would be alternative malloc implementations - but I fail to know what good they would do me (or what bad:-). Also from Shawns reply I learned that due to memory fragmentation, my application might not be able to reserve the needed memory in one chunk, but I'm still missing the technique at hand to deal with the problem? On a side note, I keep reading that it would be good practice not to reserve many very small blocks but rather one large chunk and re-use that. However, I fail to understand when this good practice is needed and when not - or better said, for common practice there should be a sample implementation that does it for me? Or some technotes on how to implement it? Same goes for Shawns recommendation with sliding a window over a mmapped file - it sounds ingenious, but I would rather not write it from scratch as to avoid errors or performance penalties. Does anyone know an OS library or implementation I could use? _Mac OS X Internals_ by Amit Singh - the entire chapter 8 deals with Mach-specific VM. (I just bought the book a few weeks ago and am very impressed.) A very good book, I just bought it this week but haven't really started. Also, as you optimize your code, bear in mind that the memory figures for any given app doesn't necessarily reflect the app's complexity. For example, building a Cocoa app with a single blank window claims ~300 MB virtual memory. My point being, don't lose too much sleep over why your app is using X memory - it could be perfectly normal. True, but I'm also keen on finally understanding what this vm-stuff in my address space does (and if its going to be nice to me or not:-)) Best, Mario _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Dave Keck wrote: This email sent to site_archiver(a)lists.apple.com

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Re: confusion about memory fragmentation, vm, and blocks
by Dave Keck 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=hv7TYo/AHofx2rmRELVoqVK/1M33xEZz9oBVkGs+tDo=; b=iadchwJad79pQnfSgELsTCi1WB8t26RytKtutBqSGcTOoRxI//JuFag2RXc7gCbU2a wOd0W+V4ylVgRugyFKDdLVlFfcP1IKt/F+2PpLSPUyjkG2avC57UTMiLGOLHJiR3ROxy YviZN/jWBcqbbds6VRldam0LytHMG8allqBns= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=jQbfpDdaIQRiCGh5HmG9Pyc8fqLOqur/uuCBe/bS2ozY2MtJ3C1dRFeU8i34RtF0n7 rijIak0c9oAfu4lHyp/rFXLZGH+sKLQ41dnyLe/Oz3mlrDIyK6QzbRPYs8oyBeCcIdh2 +xBZNcrc6tbS+cg3UH7f55dshvqOzD0IYgSio= > Can I read up details about that pre-allocated space? Is there a good > tutorial or technote? > I understand it is quite a lot VM that my application consumes upon startup, > about 1GB. It seems a fair amount given that I do 3D rendering and whatnot, > but I would still be curious to reduce it. (I've asked about that in > a separate thread (Why is virtual memory so high? (crash)) a while ago, > but have not yet found a definitive conclusion. Try reading up on virtual memory in general - many of the VM principles used by Mach aren't Mach-specific. Also, take a look at _Mac OS X Internals_ by Amit Singh - the entire chapter 8 deals with Mach-specific VM. (I just bought the book a few weeks ago and am very impressed.) Also, as you optimize your code, bear in mind that the memory figures for any given app doesn't necessarily reflect the app's complexity. For example, building a Cocoa app with a single blank window claims ~300 MB virtual memory. My point being, don't lose too much sleep over why your app is using X memory - it could be perfectly normal. Good luck, David _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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snowleopard: opencl and grandcentral
by Joel Reymont 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:from:to :content-type:content-transfer-encoding:mime-version:subject:date :x-mailer; bh=m6wS363dAyIeKAN+DaTgzmvT+caMJCX/Fo0Sz8moOVg=; b=rKFuOiZfbdoeB0qprpp/TF0etpvzzS9SAm1FgK9ddz5PCaYyaTos3+jP4fKC2Isyyz gY/szpFnW6HLMUs6iH2TrEhTJhU2rnvbBqLnAdvdHdVK3Gxe5Kfg1EGMelvkkRcQ0c2i pekFy2r+vy+388eqmOoA7/tGORQlw52yk3mVs= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:content-type:content-transfer-encoding :mime-version:subject:date:x-mailer; b=xSmyCrJeGEUPFdzK/ZMsnSeqkOuDDPUzhkhh1tomiUet2CNM0l5UqZpTcQC3kiuRrZ Ob9R6k572kDcOn9HdKU2WutBsocDUA+FVCpflPql3IN4bDG5RNiTcIAayCgVaf1Xtuzu H9DhbpOI+U7qPfI1Zj0Xpr+bJTdy259plmkFo= Please feel free to reply privately. Thanks, Joel --- http://tinyco.de Mac, C++, OCaml _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Where do you look for OpenCL and Grand Central information once you are set up on the latest seed of Snow Leopard? This email sent to site_archiver(a)lists.apple.com

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Re: confusion about memory fragmentation, vm, and blocks
by Mario Emmenlauer 05 Mar '09

05 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Thunderbird 2.0.0.18 (Macintosh/20081105) Hi Shawn, The amount of memory your application can address at a given time is limited first by the size of the virtual memory space, minus reserved/invalid/guard pages, minus pages mapped for shared libraries, minus pages mapped for use by the OS, etc., minus allocations made by your code. All of these allocations carve out ranges in your virtual address space with the unused ranges between them representing "available" memory to your application. Can I read up details about that pre-allocated space? Is there a good tutorial or technote? I understand it is quite a lot VM that my application consumes upon startup, about 1GB. It seems a fair amount given that I do 3D rendering and whatnot, but I would still be curious to reduce it. (I've asked about that in a separate thread (Why is virtual memory so high? (crash)) a while ago, but have not yet found a definitive conclusion. When you allocate (malloc, etc.) a buffer you get back a pointer to a contiguous virtual memory range (how the API is defined). If you attempt to allocate a buffer larger then any of the available contiguous virtual memory ranges it will fail... despite possibly having smaller contiguous ranges available that, if contiguous, would have allow the allocation to succeed. (note I side stepped "pools" of virtual memory pages that malloc maintains for small, tiny, etc. allocations to minimize fragmentation and speed re/allocations) That answers the question perfectly, thanks! You could consider using a memory mapped file and slide around a "window" of contiguous mappings over that file. This would limit/bound how much virtual memory you use at a given time while giving you access to an arbitrarily large buffer. ...of course it would be far I haven't done anything like it before, but it sounds very useful - you would not by any chance know a good book or tutorial on the subject? We have done that just now, ported our code to x86_64. The topic remains merely because I assume we could improve our memory management. Best regards, Mario _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Shawn Erickson wrote: On Tue, Mar 3, 2009 at 7:57 AM, Mario Emmenlauer <mario(a)emmenlauer.de> wrote: I have a problem understanding memory allocation, blocks and fragmentation. easier to switch your application to use a 64b virtual address space. This email sent to site_archiver(a)lists.apple.com

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Re: Recommendations on uniquely identifying a system.
by Axel Luttgens 04 Mar '09

04 Mar '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Le 4 mars 09 à 23:40, Tom Fortmann a écrit : Hello Tom, TIA, Axel _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… That was my first thought, but we have a requirement that the value persist across installs, and I don't like leaving a preference file behind on uninstalls. So, using one or more of these values seems to be the best solutions. I'm just trying to find out if Apple is moving away from Mac addresses for this purpose. With no real documentation on the IOPlatformUUID value I think I will use a combination of the Mac address and serial number a unique ID string. I may factor in the IOPlatformUUID value if for some reason the serial number is missing. It still isn't clear wether you are interested in tracking a very precise piece of hardware or a very precise registration against a server (whatever it is, since you didn't tell anything about it). Unless I'm wrong, these could be very different things. Could you elaborate? This email sent to site_archiver(a)lists.apple.com

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