Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
On Mon, Aug 27, 2001 at 04:08:25PM +0200, Pavel Novy wrote: ... I agree this is an undesirable way for bitfields to be aligned, but this agrees with MSVC, upon which we based the bitfield layout. (In MSVC the smallest we can make the struct is 4 bytes!) I think the way to work around this is to change the bitfield base type to unsigned char. The type of the bitfield is used in determining how it is aligned; thus, using a smaller type will require a smaller alignment. ... --- util_uri.h.orig Mon Feb 26 16:49:32 2001 +++ util_uri.hMon Aug 27 15:44:41 2001 @@ -106,10 +106,10 @@ unsigned short port; /* The port number, numeric, valid only if port_str != NULL */ -unsigned is_initialized:1; +unsigned char is_initialized:1; -unsigned dns_looked_up:1; -unsigned dns_resolved:1; +unsigned char dns_looked_up:1; +unsigned char dns_resolved:1; } uri_components; Screw the bitfields. Just change all of them to plain old unsigned chars. (and apr_byte_t in APR). There is no reason to be miserly with bits here. Cheers, -g -- Greg Stein, http://www.lyra.org/
Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
Hi, William A. Rowe, Jr. wrote: From: "Pavel Novy" [EMAIL PROTECTED] Sent: Monday, August 27, 2001 9:08 AM I suggest to fix the problem as described (patch attached), even if it will be considered as CodeWarrior's bug (and fixed, then) by Metrowerks or not. I've detailedly analyzed the issue and I see no way how to stay backwardly compatible with this issue, so all binaries for NetWare platform (Apache core+modules from CVS sources and all "3rd party" external modules produced with CW) should be re-built after the fix (if it will be commited) - it will not be possible to mix new NLMs with older Apache core or modules. I have tested the fix with CW 5.3 and gcc 2.95.3 and it seems that alignment of problematic structures is the same (it differs from current status quo, of course). The change in the source file shared on all platforms is requested, so verification on these ones will be needed. I don't expect problems (no change in alignment) on platforms where the GNU stuff is used (gcc). Thanks. Pavel, I'm sorry, I cannot see this code change for the 1.3 generation. I sympathize that the implementors on the Netware platform refuse to see eye to eye (or even attempt to bring some sort of compatiblity options to the table.) And the unsigned char solution is very slow, compared to integer manipulation, so I'm not sure we would choose that anyways. I don't know how much are you familiar with the bitfields and gcc, but I've spend enough hours analyzing this weird issue already... I have tested with gcc 2.95.2 on Linux - it is obvious that this change in the base type doesn't affect speed of produced code. Please take a look on attached sample (especially .s files) to see differences with changed base type to char, short, int and long. The bitfield is very specific kind of C(++) type and gcc implements it the following way: the smallest amount of memory is used to store merged "bit elements" used in a struct - if it fits into char (8 bits), then one byte is used to store/access whole bitfield (gcc, Watcom). There is the essential difference in implementation of the bitfields between gcc and CodeWarrior and it is the source of the problem. I am not able to decide which implementation is wrong and which is not (even if that used in CW is very unusual), but I am pretty sure, that proposed change causes no problems on Linux platform (not sure for other ones). The problems expected on NetWare platform I've described already. Please bring this discussion to Apache 2.0. I know Brad Nicholes and company at Novell are working hard to support Apache 2.0. This implementation will be a far more secure and stable platform than the 1.3 hybrid/threaded implementations (win32/os2/netware etc.) I believe that they are doing their job well (and it is hard) and hoping that version 2.0 of the Apache server will be the best one ever. However, even if version 1.3 is ugly in some cases, it is the only one version currently available for NetWare platform. My target was build the Apache server for NetWare from the CVS sources with GNU stuff and I have succeeded with this, so I hope it will be supported way by default in 2.0. In other case I will be in the same situation like I was with version 1.3, when some new sources for NetWare platform will be out. If we direct our energies at solving the problem there, and we can agree on a mechansim, I see this issue being resolved in Apache 2.0. Bill There are no sources for NetWare platform available yet, so I can't do anything with this. I don't really want to waste developers' time, but version 1.3 is still the current one... Regards, Pavel P.S.: BTW, another way how to solve the problem without changes in the sources is to throw CodeWarrior away and use gcc as a tool for all target platforms... (But it is impossible to do it just now.) bitfield-sample.zip
Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
Hi Brad, About 90% of the NetWare specific changes for the APR layer have been checked into CVS. I am still working on the final 10% (which is usually the hardest). It may not look that way only because we were able to piggy back most of the NetWare code on Unix. This is a good thing for us because it means that we didn't have to rewrite a lot of code. I still have to organize some of the platform specific header files and get some of the kinks worked out in the project file, but we are close to having and APR layer that should work with the HTTPD server. In theory as soon as we get APR complete, there shouldn't be any additional work necessary to make Apache 2.0 run. Of course a theory is just a theory until it is proven and we won't have the proof until APR is complete for NetWare :). thanks for your detailed info! And please dont misunderstand me: I dont want to say something against your work, it was just only to tell Bill that we are currently unable to look at 2.0... Can you please post here when you have checked in all files needed for building a 2.0 version? Thanks, Guenter.
Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
From: "Pavel Novy" [EMAIL PROTECTED] Sent: Monday, August 27, 2001 9:08 AM I suggest to fix the problem as described (patch attached), even if it will be considered as CodeWarrior's bug (and fixed, then) by Metrowerks or not. I've detailedly analyzed the issue and I see no way how to stay backwardly compatible with this issue, so all binaries for NetWare platform (Apache core+modules from CVS sources and all "3rd party" external modules produced with CW) should be re-built after the fix (if it will be commited) - it will not be possible to mix new NLMs with older Apache core or modules. I have tested the fix with CW 5.3 and gcc 2.95.3 and it seems that alignment of problematic structures is the same (it differs from current status quo, of course). The change in the source file shared on all platforms is requested, so verification on these ones will be needed. I don't expect problems (no change in alignment) on platforms where the GNU stuff is used (gcc). Thanks. Pavel, I'm sorry, I cannot see this code change for the 1.3 generation. I sympathize that the implementors on the Netware platform refuse to see eye to eye (or even attempt to bring some sort of compatiblity options to the table.) And the unsigned char solution is very slow, compared to integer manipulation, so I'm not sure we would choose that anyways. Please bring this discussion to Apache 2.0. I know Brad Nicholes and company at Novell are working hard to support Apache 2.0. This implementation will be a far more secure and stable platform than the 1.3 hybrid/threaded implementations (win32/os2/netware etc.) If we direct our energies at solving the problem there, and we can agree on a mechansim, I see this issue being resolved in Apache 2.0. Bill --- util_uri.h.orig Mon Feb 26 16:49:32 2001 +++ util_uri.h Mon Aug 27 15:44:41 2001 @@ -106,10 +106,10 @@ unsigned short port; /* The port number, numeric, valid only if port_str != NULL */ -unsigned is_initialized:1; +unsigned char is_initialized:1; -unsigned dns_looked_up:1; -unsigned dns_resolved:1; +unsigned char dns_looked_up:1; +unsigned char dns_resolved:1; } uri_components;
Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
Hi Bill, Please bring this discussion to Apache 2.0. I know Brad Nicholes and company at Novell are working hard to support Apache 2.0. This implementation will be a far more secure and stable platform than the 1.3 hybrid/threaded implementations (win32/os2/netware etc.) If we direct our energies at solving the problem there, and we can agree on a mechansim, I see this issue being resolved in Apache 2.0. at this time we cannot discuss anything about NetWare and 2.0 because the NetWare OS dependent files are not in CVS tree so we cannot build a 2.0 NetWare version... Guenter.
Re: [PATCH] Apache 1.3.21-dev for NetWare builds (5)
Guenter, About 90% of the NetWare specific changes for the APR layer have been checked into CVS. I am still working on the final 10% (which is usually the hardest). It may not look that way only because we were able to piggy back most of the NetWare code on Unix. This is a good thing for us because it means that we didn't have to rewrite a lot of code. I still have to organize some of the platform specific header files and get some of the kinks worked out in the project file, but we are close to having and APR layer that should work with the HTTPD server. In theory as soon as we get APR complete, there shouldn't be any additional work necessary to make Apache 2.0 run. Of course a theory is just a theory until it is proven and we won't have the proof until APR is complete for NetWare :). thanks, Brad [EMAIL PROTECTED] Monday, August 27, 2001 10:05:23 AM Hi Bill, Please bring this discussion to Apache 2.0. I know Brad Nicholes and company at Novell are working hard to support Apache 2.0. This implementation will be a far more secure and stable platform than the 1.3 hybrid/threaded implementations (win32/os2/netware etc.) If we direct our energies at solving the problem there, and we can agree on a mechansim, I see this issue being resolved in Apache 2.0. at this time we cannot discuss anything about NetWare and 2.0 because the NetWare OS dependent files are not in CVS tree so we cannot build a 2.0 NetWare version... Guenter.
