diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/man/arc4random.3 | 110 | ||||
| -rw-r--r-- | docs/man/ldconfig.8 | 73 | ||||
| -rw-r--r-- | docs/man/ldd.1 | 17 | ||||
| -rw-r--r-- | docs/porting.txt (renamed from docs/PORTING) | 19 | ||||
| -rw-r--r-- | docs/probe_math_exception.c | 64 | ||||
| -rw-r--r-- | docs/sigaction.txt | 249 |
6 files changed, 4 insertions, 528 deletions
diff --git a/docs/man/arc4random.3 b/docs/man/arc4random.3 deleted file mode 100644 index 933d2eb0c..000000000 --- a/docs/man/arc4random.3 +++ /dev/null @@ -1,110 +0,0 @@ -.\" $OpenBSD: arc4random.3,v 1.19 2005/07/17 08:50:55 jaredy Exp $ -.\" -.\" Copyright 1997 Niels Provos <provos@physnet.uni-hamburg.de> -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 3. All advertising materials mentioning features or use of this software -.\" must display the following acknowledgement: -.\" This product includes software developed by Niels Provos. -.\" 4. The name of the author may not be used to endorse or promote products -.\" derived from this software without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR -.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES -.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. -.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, -.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT -.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF -.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -.\" -.\" Manual page, using -mandoc macros -.\" -.Dd April 15, 1997 -.Dt ARC4RANDOM 3 -.Os -.Sh NAME -.Nm arc4random , -.Nm arc4random_stir , -.Nm arc4random_addrandom -.Nd arc4 random number generator -.Sh SYNOPSIS -.Fd #include <stdlib.h> -.Ft uint32_t -.Fn arc4random "void" -.Ft void -.Fn arc4random_stir "void" -.Ft void -.Fn arc4random_addrandom "u_char *dat" "int datlen" -.Sh DESCRIPTION -The -.Fn arc4random -function provides a high quality 32-bit pseudo-random -number very quickly. -.Fn arc4random -seeds itself on a regular basis from the kernel strong random number -subsystem described in -.Xr random 4 . -On each call, an ARC4 generator is used to generate a new result. -The -.Fn arc4random -function uses the ARC4 cipher key stream generator, -which uses 8*8 8-bit S-Boxes. -The S-Boxes can be in about (2**1700) states. -.Pp -.Fn arc4random -fits into a middle ground not covered by other subsystems such as -the strong, slow, and resource expensive random -devices described in -.Xr random 4 -versus the fast but poor quality interfaces described in -.Xr rand 3 , -.Xr random 3 , -and -.Xr drand48 3 . -.Pp -The -.Fn arc4random_stir -function reads data from a pseudo-random device, usually -.Pa /dev/urandom, -and uses it to permute the S-Boxes via -.Fn arc4random_addrandom . -.Pp -There is no need to call -.Fn arc4random_stir -before using -.Fn arc4random , -since -.Fn arc4random -automatically initializes itself. -.Sh SEE ALSO -.Xr rand 3 , -.Xr rand48 3 , -.Xr random 3 -.Sh HISTORY -An algorithm called -.Pa RC4 -was designed by RSA Data Security, Inc. -It was considered a trade secret. -Because it was a trade secret, it obviously could not be patented. -A clone of this was posted anonymously to USENET and confirmed to -be equivalent by several sources who had access to the original cipher. -Because of the trade secret situation, RSA Data Security, Inc. can do -nothing about the release of the ARC4 algorithm. -Since -.Pa RC4 -used to be a trade secret, the cipher is now referred to as -.Pa ARC4 . -.Pp -These functions first appeared in -.Ox 2.1 . diff --git a/docs/man/ldconfig.8 b/docs/man/ldconfig.8 deleted file mode 100644 index 208d63df1..000000000 --- a/docs/man/ldconfig.8 +++ /dev/null @@ -1,73 +0,0 @@ -.TH LDCONFIG 8 2005-08-15 uClibc "Linux Programmer's Manual" -.SH NAME -ldconfig \- updates symlinks and cache for shared libraries -.SH SYNOPSIS -.B ldconfig -[ -.B -DvqnNX -] [ -.B -f conf -] [ -.B -C cache -] [ -.B -r root -] -.B dir ... -.br -.B ldconfig -l -[ -.B -Dv -] -.B lib ... -.br -.B ldconfig -p -.SH DESCRIPTION -.B ldconfig -creates the necessary links and cache to the most recent shared libraries -found in the directories specified on the command line, in the file -\fI/etc/ld.so.conf\fR, and in the default trusted directories (\fI/lib\fR and -\fI/usr/lib\fR). The cache is used by the run-time linker. -.B ldconfig -checks the header and file names of the libraries it encounters when -determining which versions should have their links updated. - -.B Note: -Some features may not exist depending on how uClibc was built -.SH OPTIONS -.TP -.B -C cache -use specified \fIcache\fR instead of default -.TP -.B -D -debug mode, do not update links -.TP -.B -f conf -use specified \fIconf\fR instead of default -.TP -.B -l -library mode, manually link libraries -.TP -.B -n -do not process standard trusted directories -.TP -.B -N -do not update the library cache -.TP -.B -p -print the current library cache -.TP -.B -q -quiet mode, do not print warnings you should actually be reading -.TP -.B -r root -chroot to \fIroot\fR before running -.TP -.B -v -verbose mode, print things as we go, and generally be annoying -.TP -.B -X -do not update the library links -.SH BUGS -Probably, make sure you complain when you find them: -.br -http://bugs.uclibc.org/ diff --git a/docs/man/ldd.1 b/docs/man/ldd.1 deleted file mode 100644 index 0b69f730d..000000000 --- a/docs/man/ldd.1 +++ /dev/null @@ -1,17 +0,0 @@ -.TH LDD 1 2005-08-15 uClibc "Linux Programmer's Manual" -.SH NAME -ldd \- Print shared library dependencies -.SH SYNOPSIS -.B ldd -[ -.B OPTIONS -] -.B FILE ... -.SH DESCRIPTION -Prints shared library dependencies. -.SH OPTIONS -None actually, we lied about that part. -.SH BUGS -Probably, make sure you complain when you find them: -.br -http://bugs.uclibc.org/ diff --git a/docs/PORTING b/docs/porting.txt index d04f3b4f5..380645801 100644 --- a/docs/PORTING +++ b/docs/porting.txt @@ -57,12 +57,6 @@ you are hacking on. write them in C ... see other ports for more information ==================== -=== pthread deps === -==================== - -TODO: nptl / linuxthreads / linuxthreads.old - -==================== === ldso sysdeps === ==================== - elf.h - presumably you've already taught binutils all about the random ELF @@ -72,17 +66,12 @@ TODO: nptl / linuxthreads / linuxthreads.old - enable ldso/shared options in your extra/Configs/Config.ARCH file - you will need to create the following files in ldso/ldso/ARCH/ - dl-debug.h dl-startup.h dl-syscalls.h dl-sysdep.h elfinterp.c resolve.S - -- dl-debug.h: define string versions of all the relocations of your arch in the - _dl_reltypes_tab array ... the index should match the actual reloc type, so - if the value of say R_X86_64_PC16 is 13, then "R_X86_64_PC16" better be at - index 13 of the array + dl-startup.h dl-syscalls.h dl-sysdep.h elfinterp.c resolve.S - dl-startup.h: - define the _start function which should call _dl_start which takes just one parameter ... a pointer to argc (usually on the stack) - glibc stores this function in libc/sysdeps/ARCH/dl-machine.h as RTLD_START + glibc stores this function in sysdeps/ARCH/dl-machine.h as RTLD_START - define the GET_ARGV() macro which calculates the value of argv based upon the parameter passed to _dl_start (usually it's simply just ARGS+1) - define PERFORM_BOOTSTRAP_RELOC() macro which will handle just the relocs @@ -105,7 +94,7 @@ TODO: nptl / linuxthreads / linuxthreads.old - define elf_machine_type_class() macro - define the inline functions elf_machine_dynamic, elf_machine_load_address, and elf_machine_relative - glibc stores a bunch of these values in libc/sysdeps/ARCH/dl-machine.h + glibc stores a bunch of these values in sysdeps/ARCH/dl-machine.h - elfinterp.c: define all the relocation functions ... it's best if you just copy from @@ -119,7 +108,7 @@ TODO: nptl / linuxthreads / linuxthreads.old - call _dl_linux_resolver() - clean up after call - jump to function address now stored in PLT - glibc stores this function in libc/sysdeps/ARCH/dl-trampoline.S + glibc stores this function in sysdeps/ARCH/dl-trampoline.S - utils/ldd.c - if you want support for ldso cache files (spoiler: you do), then you'll need to teach ldd a little. generally, the fallback code diff --git a/docs/probe_math_exception.c b/docs/probe_math_exception.c deleted file mode 100644 index dbc9020d4..000000000 --- a/docs/probe_math_exception.c +++ /dev/null @@ -1,64 +0,0 @@ -/* Small test program for probing how various math functions - * with specific operands set floating point exceptions - */ - -#define _ISOC99_SOURCE 1 -#define _GNU_SOURCE 1 - -#include <stdint.h> -#include <math.h> -#include <fenv.h> -#include <stdio.h> - -int main(int argc, char **argv) -{ - float largest, small, t, inf_float; - - largest = small = 1; - while (1) { - t = largest + small; - /* optimizations may make plain "t == largest" unreliable */ - if (memcmp(&t, &largest, sizeof(float)) == 0) - break; - if (isfinite(t)) { - largest = t; - small *= 2; - continue; - } - small /= 2; - } - inf_float = largest + largest; - //printf("%.40g ", largest); - //printf("[%llx]\n", (long long) (*(uint32_t *)&largest)); - - feclearexcept(FE_ALL_EXCEPT); - - //t = 1.0 / 0.0; // simple test: FE_DIVBYZERO - //t = nextafterf(largest, 1); // glibc 2.8: no math exceptions raised - //t = nextafterf(largest, largest); // glibc 2.8: no math exceptions raised - //t = nextafterf(largest, inf_float); // glibc 2.8: FE_INEXACT FE_OVERFLOW - -#define PREX(ex) do { if (fetestexcept(ex)) printf(#ex " "); } while(0) -#ifdef FE_INEXACT - PREX(FE_INEXACT); -#endif -#ifdef FE_DIVBYZERO - PREX(FE_DIVBYZERO); -#endif -#ifdef FE_UNDERFLOW - PREX(FE_UNDERFLOW); -#endif -#ifdef FE_OVERFLOW - PREX(FE_OVERFLOW); -#endif -#ifdef FE_INVALID - PREX(FE_INVALID); -#endif - if (fetestexcept(FE_ALL_EXCEPT)) - printf("\n"); - else - printf("no math exceptions raised\n"); - - printf("%.40g\n", t); - return 0; -} diff --git a/docs/sigaction.txt b/docs/sigaction.txt deleted file mode 100644 index 667eeba41..000000000 --- a/docs/sigaction.txt +++ /dev/null @@ -1,249 +0,0 @@ - All what you never wanted to know about sigaction(), - struct sigaction, and sigset_t. - - -Before vda started messing with sigset_t, struct sigaction -and sigaction() functions, things looked this way: - - - Structures - -MIPS: - -Ignoring bogus "#if defined(__mips__) ..." block in -libc/sysdeps/linux/common/bits/kernel_sigaction.h -and using -libc/sysdeps/linux/mips/bits/kernel_sigaction.h -as an authoritative source: - -HAVE_SA_RESTORER is #defined -struct old_kernel_sigaction { - unsigned sa_flags; - sighandler_t k_sa_handler; - unsigned long sa_mask; - unsigned pad0[3]; /* reserved, keep size constant */ - /* Abi says here follows reserved int[2] */ - void (*sa_restorer)(void); -#if (_MIPS_SZPTR < 64) - /* For 32 bit code we have to pad struct sigaction to get - * constant size for the ABI */ - int pad1[1]; /* reserved */ -#endif -}; -struct kernel_sigaction { - unsigned int sa_flags; - sighandler_t k_sa_handler; - kernel_sigset_t sa_mask; - void (*sa_restorer)(void); - int s_resv[1]; /* reserved */ -}; -struct sigaction { - unsigned sa_flags; - sighandler_t sa_handler; - sigset_t sa_mask; - /* The ABI says here are two unused ints following. */ - /* Restore handler. */ - void (*sa_restorer)(void); -#if _MIPS_SZPTR < 64 - int sa_resv[1]; -#endif -}; - -IA64: - -Has no old_sigaction. What a relief. - -struct kernel_sigaction { - sighandler_t k_sa_handler; - unsigned long sa_flags; - sigset_t sa_mask; -}; -struct sigaction { - sighandler_t sa_handler; - unsigned long sa_flags; - sigset_t sa_mask; -}; - -Alpha: - -struct old_kernel_sigaction { - sighandler_t k_sa_handler; - unsigned long sa_mask; - unsigned sa_flags; -}; -struct kernel_sigaction { - sighandler_t k_sa_handler; - unsigned sa_flags; - sigset_t sa_mask; -}; -struct sigaction { - sighandler_t sa_handler; - sigset_t sa_mask; - unsigned sa_flags; -}; - -HPPA: - -struct kernel_sigaction { - sighandler_t k_sa_handler; - unsigned long sa_flags; - sigset_t sa_mask; -}; -struct sigaction { - sighandler_t sa_handler; - unsigned long sa_flags; - sigset_t sa_mask; -}; - -The rest, kernel side: - -HAVE_SA_RESTORER #defined -struct old_kernel_sigaction { - sighandler_t k_sa_handler; - unsigned long sa_mask; - unsigned long sa_flags; - void (*sa_restorer)(void); -}; -struct kernel_sigaction { - sighandler_t k_sa_handler; - unsigned long sa_flags; - void (*sa_restorer)(void); - sigset_t sa_mask; -}; - -On userspace side, Sparc has special struct sigaction: - -struct sigaction { - sighandler_t sa_handler; - sigset_t sa_mask; - unsigned long sa_flags; - void (*sa_restorer)(void); /* Not used by Linux/Sparc */ -}; - -And finally the rest has: - -struct sigaction { - sighandler_t sa_handler; - sigset_t sa_mask; - int sa_flags; - void (*sa_restorer)(void); -}; - -Userspace sigset_t was uniformly defined as vector of longs -big enough to hold 1024 (!) bits - carried over from glibc. -Since the only arch whose struct kernel_sigaction contains sa_mask -not as a last member is MIPS, MIPS has special kernel_sigset_t, -which is an array of longs long enough for 128 bits. -Other arches still used userspace sigset_t in struct kernel_sigaction, -but it did not really matter because overlong kernel_sigaction -does not hurt in sigaction() [explained below]. -On kernel side, all arches define _NSIG to 65 (meaning -there are 64 signals, 1..64) except MIPS, which define it to 129. - - - Functions - -sigaction() [libc function] usually has two kernel_sigaction's -on stack and copy (userspace) struct sigaction members into -first one, executes syscall, then pulls out the result from -second one. This accomodates differences in layouts of structs. - -The only typically present quirk is what to do with sa_restorer. - - libc/sysdeps/linux/arm/sigaction.c - -if HAVE_SA_RESTORER and (sa_flags & SA_RESTORER) is not set, -sets sa_restorer to -(flags & SA_SIGINFO) ? __default_rt_sa_restorer : __default_sa_restorer, -and sets SA_RESTORER, -otherwise passes it as-is. Which is kinda strange, because AFAICS -HAVE_SA_RESTORER is *not* defined for ARM. - - libc/sysdeps/linux/i386/sigaction.c - -Forcibly sets SA_RESTORER and sa_restorer: -kact.sa_flags = act->sa_flags | SA_RESTORER; -kact.sa_restorer = ((act->sa_flags & SA_SIGINFO) ? &restore_rt : &restore); - - libc/sysdeps/linux/x86_64/sigaction.c - -Forcibly sets SA_RESTORER and sa_restorer: -kact.sa_flags = act->sa_flags | SA_RESTORER; -kact.sa_restorer = &restore_rt; - - libc/sysdeps/linux/mips/sigaction.c - -# ifdef HAVE_SA_RESTORER -# if _MIPS_SIM == _ABIO32 - kact.sa_restorer = act->sa_restorer; -# else - kact.sa_restorer = &restore_rt; -# endif -# endif -No confusion here, HAVE_SA_RESTORER is #defined for MIPS - - libc/sysdeps/linux/avr32/sigaction.c - -if (kact.sa_flags & SA_RESTORER) { - kact.sa_restorer = act->sa_restorer; -} else { - kact.sa_restorer = __default_rt_sa_restorer; - kact.sa_flags |= SA_RESTORER; -} -Does not check HAVE_SA_RESTORER, but avr32 falls -in "completely ordinary" category on both kernel and -userspace sides, and those have it defined. - - libc/sysdeps/linux/xtensa/sigaction.c - -if (kact.sa_flags & SA_RESTORER) { - kact.sa_restorer = act->sa_restorer; -} else { - kact.sa_restorer = __default_sa_restorer; - kact.sa_flags |= SA_RESTORER; -} -Thus, similar to avr32. - - libc/signal/sigaction.c (i.e. the all other arches) - -# ifdef HAVE_SA_RESTORER - kact.sa_restorer = act->sa_restorer; -# endif -Plain translation, just sa_restorer copy is protected -by HAVE_SA_RESTORER #define check. Looks like here -HAVE_SA_RESTORER will be undef'ed only for IA64, -Alpha an HPPA. - - - Proposed overhaul past 0.9.30 - -Since we can define libc-side structures at will: -make sigset_t and struct sigaction identical on kernel side and libc side -within each arch. If arches do not need special handling of sa_restorer, -then sigaction() can directly use passed struct sigaction as-is. -Otherwise, a copy is still needed, although sigaction() might have -just one struct kernel_sigaction on stack and use it both for passing -data to kernel and for receiving it back. Might save a few bytes. - -To this effect: - -* Make sigset_t size match kernel side on all arches. - This is easy since all arches have 64 signals and only MIPS has 128. - -* Modify libc/sysdeps/linux/$ARCH/bits/sigaction.h - so that its struct sigaction matches kernel's. If sa_restorer - field is present in libc but is missing in kernel_sigaction, - add it at the bottom in order to not mess up kernel_sigaction layout. - -* Modify libc/sysdeps/linux/$ARCH/sigaction.c - to implement the logic above. In "common" pseudo-arch - (libc/signal/sigaction.c file), - we would not even need to do any copying, as described above. - -* Document discovered arch quirks while debugging this mess. - -* struct old_kernel_sigaction can't be disposed of in a similar way, - we need to have userspace struct sigaction unchanged regardless - whether we use "old" or "new" kernel sigaction() syscall. - It's moot anyway because "old" one is long unused, it's from - pre-2.2 kernels. |