Ros-dev March 2005

ros-dev@reactos.org

64 participants
200 discussions

Re: [ros-dev] New proposed frontpage for reactos.com

by Steven Edwards

--- Jason Filby <jason.filby(a)gmail.com> wrote: > None of the links go anywhere yet. ezPublish will be phased out and > most of the content hosted in a wiki (editable only by people trusted > in the project). > > The wiki/forums/blogs would require a bit of a face-lift so as to look similar. > > Comments? I like it except I think the description of what ReactOS is needs to say something like "A effort to create a FreeSoftware replacement for Microsoft Windows(TM) that is compatbile with existing hardware and software". It does not violate trademark as we are describing what we do. Thanks Steven __________________________________ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/

20 years

Re: [ros-svn] [hbirr] 14296: - Guarded the calls to IoSetCancelRoutine with IoAcquireCancelSpinLock/IoReleaseCancelSpinLock.

by Filip Navara

hbirr(a)svn.reactos.com wrote: >- Guarded the calls to IoSetCancelRoutine with IoAcquireCancelSpinLock/IoReleaseCancelSpinLock. >- Used a fastmutex as lock for the data queue. >- Used paged pool for the data buffers. >- Allowed the server to read (and to wait) on a listening pipe. >- Implemented the non blocking read operations. > >Updated files: >trunk/reactos/drivers/fs/np/create.c >trunk/reactos/drivers/fs/np/fsctrl.c >trunk/reactos/drivers/fs/np/npfs.c >trunk/reactos/drivers/fs/np/npfs.h >trunk/reactos/drivers/fs/np/rw.c > > This change seems to break RPC connection reads. I'm currently busy working on other things so I can't look at the problem. Any help is appreciated... (little test application attached, source available on request or in PSDK examples) - Filip

20 years

Service Control Manager, Plug and Pray, SMB and RPC

by Steven Edwards

Hi, Am I correct in understanding we are going to need a real rpc implementation to correctly support Plug and Play as well as Services, DCOM and SMB related stuff? I know the Wine DCOM and Service Code does everything over named pipes on the local system but I assume we want to do things "properly". Should we look at doing a mingw build of FreeDCE or the DEC-RPC? I am happy to try and help import any code if it will help. Thanks Steven __________________________________ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/

20 years

Re: [ros-dev] Re: [ros-svn] [gvg] 14302: Build freeldr as elf executable, initial Xen support

by Steven Edwards

--- Filip Navara <xnavara(a)volny.cz> wrote: > Just to let you know, there's no need to change the wide-character > string literals. You can use the -fshort-wchar GCC switch to get the > desired behaviour without touching the sources... I was under the impression short-wchar could differ depending on the platform and thats why wide-characters were a no-no in wine. Or is it that only newer gcc's support this option? Thanks Steven __________________________________ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/

20 years

RE: [ros-dev] ping Alex regarding log2() for scheduler

by Waldo Alvarez Cañizares

Hi Royce: int highest_bit ( int i ) { int ret = 0; if ( i > 0xffff ) i >>= 16, ret = 16; if ( i > 0xff ) i >>= 8, ret += 8; if ( i > 0xf ) i >>= 4, ret += 4; if ( i > 0x3 ) i >>= 2, ret += 2; return ret + (i>>1); } Guys I think I have one of those optimizations manuals for asm that actually use only one multiplication by a called ¨magic number¨ to get the first bit set. I actually don´t want to trace this code in my head but if you are searching a fast BSF replacement... It was tested using brute force for the 2^32 possible values on the argumment. Maybe you could check the internet for ¨Agner Fog optimization¨. I have a very bad memory so maybe the name is wrong. This is all the info I can give until I get home. Ohh well i can do it myself: http://www.df.lth.se/~john_e/gems/gem0039.html It was Harley´s magic number. so I wasn´t that far. or you can read it here... I have a c version but I guess you don´t need that :) ---------------------------------------------------------------------------------------------------------- Fast BSF replacement ASM/80386 Macro EMBSF5 emulates the BSF instruction for non-zero argument <------------------------------------ remember to test for this!!!!!!! This macro utilizes an algorithm published in the news group comp.arch by Robert Harley in 1996. The algorithm converts the general problem of finding the position of the least significant set bit into a special case of counting the number of bits in a contiguous block of set bits. By computing x^(x-1), where x is the original input argument, a right-aligned contiguous group of set bits is created, whose cardinality equals the position of the least significant set bit in the original input plus 1. The input x is of the form (regular expression): {x}n1{0}m. x-1 has the form {x}n{0}(m+1), and x^(x-1) has the form {0}n{1}(m+1). This step is pretty similar to the one used by macro PREPBSF <http://www.df.lth.se/~john_e/gems/gem002e.html> , only that PREPBSF <http://www.df.lth.se/~john_e/gems/gem002e.html> creates a right-aligned group of set bits whose cardinality equals exactly the position of the least significant set bit. Harley's algorithm then employs a special method to count the number of bits in the right-aligned contiguous block of set bits. I am not sure upon which number theoretical argument it is founded, and it wasn't explained in the news group post. According to Harley, if a 32-bit number of the form 00...01...11 is multiplied by the "magic" number (7*255*255*255), then bits <31:26> of the result uniquely identify the number of set bits in that number. A 64 entry table is used to map that unique result to the bit count. Here, I have modified the table to reflect the bit position of the least significant set bit in the original argument, which is one less than the bit count of the intermediate result. I have tested the macro EMBSF5 exhaustively for all 2^32-1 possible inputs, i.e. for all 32-bit numbers except zero. Place the following table in the data segment: table db 0, 0, 0,15, 0, 1,28, 0,16, 0, 0, 0, 2,21,29, 0 db 0, 0,19,17,10, 0,12, 0, 0, 3, 0, 6, 0,22,30, 0 db 14, 0,27, 0, 0, 0,20, 0,18, 9,11, 0, 5, 0, 0,13 db 26, 0, 0, 8, 0, 4, 0,25, 0, 7,24, 0,23, 0,31, 0 And here follows the actual macro: ; ; emulate bsf instruction ; ; input: ; eax = number to preform a bsf on ( != 0 ) ; ; output: ; edx = result of bsf operation ; ; destroys: ; ecx ; eflags ; MACRO EMBSF5 mov edx,eax ; do not disturb original argument dec edx ; n-1 xor edx,eax ; n^(n-1), now EDX = 00..01..11 IFDEF FASTMUL imul edx,7*255*255*255 ; multiply by Harley's magic number ELSE mov ecx,edx ; do multiply using shift/add method shl edx,3 sub edx,ecx mov ecx,edx shl edx,8 sub edx,ecx mov ecx,edx shl edx,8 sub edx,ecx mov ecx,edx shl edx,8 sub edx,ecx ENDIF shr edx,26 ; extract bits <31:26> movzx edx,[table+edx] ; translate into bit count - 1 ENDM Note: FASTMUL can be defined if your CPU has a fast integer multiplicator, like the AMD. The IMUL replacement should run in about 8-9 cycles. Gem writer: Norbert Juffa <mailto:norbert.juffa@amd.com> last updated: 1999-09-02 ---------------------------------------------------------------------------------------------------------- >> updated micro-code << Wow where I can get this? Do you have an assembler/disassembler? I once asked Tigran Aizvian but he told me not to have the information at all. With that I could save myself some time reversing it by trial and error using the black box approach. Someday. As far as I know still Intel CPUs microcode updates are not digitally signed so it could be reprogrammed. Here's updated micro-code for BSR, if you really think AMD & Intel will actually do it... IF r/m = 0 THEN ZF := 1; register := UNDEFINED; ELSE ZF := 0; register := 0; temp := r/m; IF OperandSize = 32 THEN IF (temp & 0xFFFF0000) != 0 THEN temp >>= 16; register |= 16; FI; FI; IF (temp & 0xFF00) != 0 THEN temp >>= 8; register |= 8; FI; IF (temp & 0xF0) != 0 THEN temp >>= 4; register |= 4; FI; IF (temp & 0xC) != 0 THEN temp >>= 2; register |= 2; FI; register |= (temp>>1); FI;

20 years

RE: I think I know how uxtheme works...

by Casper Hornstrup

In copyright law it's the result that matter, not the process. To be protected by copyright law, it must be in tangible form. Looking at disassembled code is permitted by copyright law so it's only a problem if the person doing it lacks self-discipline and uses the disassembled code in a way that violates copyright law. That said, I don't believe there is a need for reverse engineering methods for implementing the majority of ReactOS and WINE. Our goal is to run Windows software on ReactOS and other free operating systems. We have some smart people on these projects. If the Windows software vendors could figure out how to use the interfaces using the public available documentation, then we can certainly implement the interfaces from that same information. If there is an interface that isn't documented, then certainly most Windows software won't use it and there is no need to implement the interface at all. Casper References: >From http://www.nus.edu.sg/intro/slides/021111_1_Wilson%20Wong.ppt What is protectable? Functionality? - not protected - must be an "expression...of a set of instructions" - Autodesk Inc v Dyason (Aust): copying function of AutoCAD lock but not code (no infringement) Program Structure? - (cf: plot elements in literary/dramatic works capable of protection) - eg. structural arrangements of modules and subroutines - yes if expression of idea, & no if ideas or functions: difficult line to draw - yes if organisation, sequence, arrangement or compilation - not protectable: elements of software which are: * ideas; * dictated by efficiency or external factors (eg h/w) specs, compatibility reqms, industry standards; or * public domain - not if similarity is due only to similar subject matter * analogy: drawing of a hand * eg any 2 word processors will have some structural similarities > -----Original Message----- > From: wine-devel-admin(a)winehq.org [mailto:wine-devel-admin@winehq.org] On Behalf Of Mike McCormack > Sent: 25. marts 2005 10:39 > To: Jonathan Wilson > Cc: wine-devel(a)winehq.org; ros-dev(a)reactos.com > Subject: Re: I think I know how uxtheme works... > > > Jonathan Wilson wrote: > > What I am doing here is clean-room reverse engineering. > > There's no reason that we need to expose ourselves to any legal risk at > all. It may be your opinion that reading assembly code and describing > it is legal and safe, but I don't agree and I'm sure others who work on > Wine don't either. > > The original IBM BIOS was clean room reverse engineered because there > was not enough documentation available for it. We have MSDN, which is > not 100% complete, but is good enough for most purposes. Other things > can be deduced from test programs. Information that cannot be deduced > by a test program is irrelevant. > > Reverse engineering does not help Wine. Casual observers will assume > that Wine is the result of reverse engineering by disassembly, which is > incorrect and harmful. > > Mike

20 years

Re: [ros-svn] [gvg] 14302: Build freeldr as elf executable, initial Xen support

by Filip Navara

gvg(a)svn.reactos.com wrote: >Build freeldr as elf executable, initial Xen support > >Added files: >... > >Updated files: >... >branches/xen/reactos/boot/freeldr/freeldr/fs/ntfs.c >... > > Just to let you know, there's no need to change the wide-character string literals. You can use the -fshort-wchar GCC switch to get the desired behaviour without touching the sources... - Filip

20 years

Re: [ros-dev] Re: Colinux crash : Lock the kernel - Debug traces for Bug512]

by Steven Edwards

Hi Hartmut, --- Hartmut Birr <hartmut.birr(a)gmx.de> wrote: > with my last changes (r14296), coLinux does start and does mount the > root partition. It exist an second problem. The coLinux window is only > shown for a very short time. I'm not so familiar with the gdi, user and > win32k code. I cannot fix the second problem. Nice! I will svn update, rebuild and test tommrow. Thanks Steven __________________________________ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/

20 years

Re: I think I know how uxtheme works...

by Jonathan Wilson

What I am doing here is clean-room reverse engineering. Essentially it involves taking existing binary modules and sources of information and writing up what they do in a way that isnt violating the copyright on the origonal (IANAL but I dont think what I posted violates the copyright on the windows binaries). Then it involves someone else who hasnt seen the origonal copyrighted source using the resulting information to re-implement whatever the information describes. As long as the person who origonally did the reverse engineering never contributes anything to the resulting code, it is (AFAIK, IAMAL) perfectly legal (after all, this is exactly what was done when the first clone PC bios was written, one group disassembled the origonal IBM BIOS and wrote up documents on how it works and how to talk to it. Then another group not connected to the people who did the origonal reverse engineering took the documentation and re-implemented the BIOS from just the documentation without looking at the orgininal IBM implementation) I never had any plans to actually write code for this (since doing so is out of my skill range) and as long as I never do so in the future (thus "tainting" the code I write as being a potential Derived Work of the microsoft code I looked at), I dont see any way that the results of this investigation could be considered a derived work of any microsoft code. Although if I have a mis-understanding of this situation, please point out what I am doing that would make code written by someone else using the information in my posts a Derived Work of microsofts origonal binaries.

20 years

Speed Tests (was: ping Alex regarding log2() for scheduler)

by Ash

Hello, I'd like to provide a small VS.NET project file with 5 different tests. - 46ffffe9 tells everything is alright with the function calculation - times are measured with QueryPerformanceCounter - loop run cnt: 0x2ffffff result orig function 46ffffe9 it took 1491052 result orig function inlined 46ffffe9 it took 1035547 result second proposal inlined 46ffffe9 it took 1244434 result optimized asm 46ffffe9 it took 1338367 result debug asm 46ffffe9 it took 8774815 The second proposal is the original proposal but more shifts - still slower tho. Interesting is the inlined version generated by MSVC, shaving off almost 1/3 of the overall time. Also stared as "optimized asm" - no gurantee on register safety tho ;) For portability and performance sake it should be considered to create a compiler macro. This function is terribly small, any optimisations inside are outweighted by the calling overhead in this case. The most impressive one is the original function inlined, althought the ASM would only work on x86. Please do not think about using 64k tables, thats what, 1/2 of a Sempron L2 cache? It would really really trash performance. Available at: <a href="http://hackersquest.org/kerneltest.html" title="Kernel Test Emulator">Kernel Test</a> <a href="http://wohngebaeudeversicherung.einsurance.de/">http://wohngebaeudeversicherung.einsurance.de</a>

20 years

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Ros-dev March 2005