Eagle and the libpng situation

I just saw the changelog of version 6.2.1:

  - Linux: libpng and libjpeg directly linked into the executable to get rid of

    dependency and availability of according system libs.

Thanks! That's a great move, we appreciate it.

On 4/11/2012 10:02 AM, S H wrote:

I know this is an old issue and people have done work arounds, but building against libpng14 did create a lot of problems for linux users whose distros do not have libpng14 (something like 4 out of the top 5 distros, and 7 out of the top 10 don't have it). It appears now that they will never have libpng14. In fact, libpng's own website encourages the use of 12 or 15...

 

Could CadSoft either:

1) build against libpng15, if possible

2) include libpng.so.14 with the release or statically link against libpng14

 

CadSoft has said that (2) is impossible for legal reasons, but that doesn't make sense. libpng's license is:

 

" Permission is hereby granted to use, copy, modify, and distribute this

   source code, or portions hereof, for any purpose, without fee, subject

   to the following restrictions:

 

   1. The origin of this source code must not be misrepresented.

 

   2. Altered versions must be plainly marked as such and

      must not be misrepresented as being the original source.

 

   3. This Copyright notice may not be removed or altered from

      any source or altered source distribution.

 

   The Contributing Authors and Group 42, Inc. specifically permit, without

   fee, and encourage the use of this source code as a component to

   supporting the PNG file format in commercial products.  If you use this

   source code in a product, acknowledgment is not required but would be

   appreciated."

 

Which allows, with no preconditions, CadSoft to include libpng14 with their binary for eagle. It explicitly says you can use it in commerical products and doesn't even require you to acknowledge that you did (although I would encourage you to). It's an extremely generous license which in fact allows you to even statically compile the library into eagle and distribute the binary that way (with the proper attribution in your readme or license file). However, that may be a security threat and thus a liabillity.

 

If you're worried about security, then you can do (1) and rely on distributions to keep the library up to date to reduce your liabillity.

 

Thanks for your consideration, and hopefully this is something that can be easily worked out.

 

Hi Guys,

Thanks for your concerns, EAGLE keeps its libraries up to date and it

will build to a newer libpng library once Suse adopts it which it will

eventually. So at worse this is a temporary problem.

These libraries have all been compiled, if you need them just e-mail

support and you'll get the libraries you need. Copy them to the usr/lib

folder and you're done.

I can't speak on behalf of the developers, but I'm sure there is a good

reason why the current situation is the way it is.

hth,

Jorge Garcia

Jim Littlefield Inscribed thus:

On 4/22/2012 11:10 AM, Seeker wrote:

>> You chose to use an operating system that has many fractured

>> dialects.  What I find annoying is when people who made a conscious

>> choice to do something, in this case using an operating system that

>> is not mainstream, whine that their particular choice is less than

>> 100% supported.  There is a reason MOST people use Windows.  It is

>> universal, and fully supported by mainstream software designers.  I

>> am a field engineer in a network consulting firm, so it is not

>> because I was led down a consumer path and had no choice.  I CHOSE

>> Windows because I know I will have full versions and full support for

>> the software I run.  If you decide to do things differently, that is

>> fine.  But don't expect the world to cater to you and your way of

>> doing things.  You are not entitled to have the world your way, none

>> of us are.  So live with your choices, or make a different choice.

>> It is all the same to me.  But don't rant and complain that the world

>> isn't following your path.

>>

>> (/soapbox)

>>

 

I think Troy may have selected Eagle (at least in part) because it is

sold as a multi-platform,  Linux capable application.   If advertised

as such I think its completely reasonable to expect that it should

work across a range of the more common distributions ...and it

probably does except for the libpng versioning issue previously

described.

 

Jim

I find Seekers post a little condescending particularly since by his own

admission Windows provides his living !

People choose Open Source alternatives because they are not Windows. As

Jim says "because it is sold as a multi-platform,  Linux capable

application.   If advertised as such I think its completely reasonable

to expect that it should work across a range of the more common

distributions"

--

Best Regards:

                     Baron.

Linux is a small market and if a company chooses not to support it, that's fine - it just appears that it can be 100% compatible and a small technical hang-up exists which should be easy to fix.

I'm grateful that CadSoft is willing to develop a cross-platform product, and I fully realize that Windows easily has the majority of paying users.

For me, the main part of the annoyance is that it's not the kind of bug that's difficult to fix. I don't think fixing it is asking much of CadSoft.

It would be nice, however, for CadSoft to at least put a note clarifying what they've tested the Linux version with.

• For Windows, they give "Windows XP, Windows Vista, Windows 7".
• For OS X, they give: "Mac OS X version 10.6 or above for Intel computer"

It'd be nice to provide a "known good" version for Linux, at the very least.

Seeker wrote:

 

You chose to use an operating system that has many fractured dialects.  What I find annoying is when people who made a conscious choice to do something, in this case using an operating system that is not mainstream, whine that their particular choice is less than 100% supported.

Honestly, that is fair (although many argue that Windows is no better with shared library support). I choose Linux, and CadSoft has chosen to make Eagle not exactly 100% compatible with Linux. My institute currently uses Eagle, but can choose to teach and use gEDA and KiCad. Debian has made the choice to not use libpng14, and will remove all packages that depend on libpng12 in the near future - thus removing Eagle from both Debian and Ubuntu's distribution (which coincidentally is the OSes of the computer lab here, guess what's going to happen to classes teaching Eagle...)

Linux is a small market and if a company chooses not to support it, that's fine - it just appears that it can be 100% compatible and a small technical hang-up exists which should be easy to fix.

On 4/22/2012 11:10 AM, Seeker wrote:

You chose to use an operating system that has many fractured dialects.  What I find annoying is when people who made a conscious choice to do something, in this case using an operating system that is not mainstream, whine that their particular choice is less than 100% supported.  There is a reason MOST people use Windows.  It is universal, and fully supported by mainstream software designers.  I am a field engineer in a network consulting firm, so it is not because I was led down a consumer path and had no choice.  I CHOSE Windows because I know I will have full versions and full support for the software I run.  If you decide to do things differently, that is fine.  But don't expect the world to cater to you and your way of doing things.  You are not entitled to have the world your way, none of us are.  So live with your choices, or make a different choice.  It is all the same to me.  But don't rant and complain that the world isn't following your path.

 

(/soapbox)

 

I think Troy may have selected Eagle (at least in part) because it is

sold as a multi-platform,  Linux capable application.   If advertised as

such  I think its completely reasonable to expect that it should work

across a range of the more common distributions ...and it probably does

except for the libpng versioning issue previously described.

Jim

You chose to use an operating system that has many fractured dialects.  What I find annoying is when people who made a conscious choice to do something, in this case using an operating system that is not mainstream, whine that their particular choice is less than 100% supported.

You've made an interesting rant yourself, but it's also not at all true. Anybody who's done software development in the real world knows that the so-called "fracture" you mention isn't unique to any one operating system. The exact same issue exists on Windows, and even has a name: DLL Hell. Library incompatibilities are a fact of life when developing software; the operating system has little to do with it. Sloppy build & release management results in incompatibility - whether you're using Windows, Linux, or anything else. Microsoft typically makes the same mistake at least once for each major release of Office.

Issues with incompatible libraries is largely a "solved" problem for most operating systems (Windows and Linux included).

Shooting yourself in the foot, on the other hand, isn't.

You chose to use an operating system that has many fractured dialects.  What I find annoying is when people who made a conscious choice to do something, in this case using an operating system that is not mainstream, whine that their particular choice is less than 100% supported.  There is a reason MOST people use Windows.  It is universal, and fully supported by mainstream software designers.  I am a field engineer in a network consulting firm, so it is not because I was led down a consumer path and had no choice.  I CHOSE Windows because I know I will have full versions and full support for the software I run.  If you decide to do things differently, that is fine.  But don't expect the world to cater to you and your way of doing things.  You are not entitled to have the world your way, none of us are.  So live with your choices, or make a different choice.  It is all the same to me.  But don't rant and complain that the world isn't following your path.

(/soapbox)

I'm dissapointed as well - I'd consider it mandatory to support the libraries in the following distributions:

• Debian
• Ubuntu
• Fedora
• Mandriva
• openSUSE

It's also really odd (to be gracious) to see that Eagle is linked to a specific version of libpng. This is a problem that has been solved long ago.

I could give more than a few criticisms, since my professional career for the past seven or so years has been building software for multiple Linux distributions. I have to handle multiple versions (old & new - and the list only grows) of a dozen or so Linux distributions, across four architectures. It seems abundantly clear that whomever builds EAGLE uses SUSE variants either - openSUSE or SLE(S,D), and "Linux" means "SuSE Linux" - otherwise they'd have at least some idea what Debian/Ubuntu and Fedora are doing. Fedora 16 doesn't have libpng14, Fedora17 won't (it's easy enough to look at the beta repositories, after all). Debian (unstable) went from libpng12 -> libpng15, so it's certain they'll never support libpng14 either. Ubuntu is essentially the same story as Debian - libpng12 -> libpng15.

Yet openSUSE 12.1, for some weird reason, went with libpng.so.14 (and this continues in openSUSE Factory, so libpng.so.14 seems to be SuSE's path going forward for at least a couple more releases.)

Is it a big deal for me to compile libpng14? Not at all. Irritating? Absolutely!

It's espescially irritating given libpng14 been mentioned (and even been recognized by the CadSoft team) some-odd four months ago, and the just-released 6.2 version is still tied to libpng14.

CadSoft has said that (2) is impossible for legal reasons, but that doesn't make sense. libpng's license is:

It doesn't make sense for a couple of reasons. In the States, at least, there isn't a meaningful legal difference between dynamically linking vs static linking of a library. If it's illegal to staticaly link the library, it's just as illegal to link it dynamically - both are considered "derived works." This is, of course, a moot point because (as you say) there's no licensing issue.

My bet is that Linux support just isn't a priority, CadSoft is either unwilling or unable to test against anything other than SUSE. It's probably a matter of applying testing resources proportional to the number of paying users, so Linux (and likely OS X) are at the bottom rung, and SUSE is the most popular distro in Germany (where EAGLE is developed).