4
http://git.openembedded.org/cgit.cgi/openembedded/tree/recipes/busybox/
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https://dev.openwrt.org/browser/trunk/package/busybox/patches/
8
Stuff that needs to be done. This is organized by who plans to get around to
9
doing it eventually, but that doesn't mean they "own" the item. If you want to
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do one of these bounce an email off the person it's listed under to see if they
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have any suggestions how they plan to go about it, and to minimize conflicts
12
between your work and theirs. But otherwise, all of these are fair game.
14
Rob Landley suggested this:
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Implement bb_realpath() that can handle NULL on non-glibc.
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The command shell situation is a mess. We have two different
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shells that don't really share any code, and the "standalone shell" doesn't
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work all that well (especially not in a chroot environment), due to apps not
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Look at the full Single Unix Specification version 3 (available online at
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"http://www.opengroup.org/onlinepubs/009695399/nfindex.html") and
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figure out which of our apps are compliant, and what we're missing that
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we might actually care about.
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Even better would be some kind of automated compliance test harness that
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exercises each command line option and the various corner cases.
33
How much internationalization should we do?
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The low hanging fruit is UTF-8 character set support. We should do this.
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See TODO_unicode file.
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We also have lots of hardwired english text messages. Consolidating this
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into some kind of message table not only makes translation easier, but
40
also allows us to consolidate redundant (or close) strings.
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We probably don't want to be bloated with locale support. (Not unless we
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can cleanly export it from our underlying C library without having to
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concern ourselves with it directly. Perhaps a few specific things like a
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config option for "date" are low hanging fruit here?)
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What level should things happen at? How much do we care about
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internationalizing the text console when X11 and xterms are so much better
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at it? (There's some infrastructure here we don't implement: The
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"unicode_start" and "unicode_stop" shell scripts need "vt-is-UTF8" and a
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--unicode option to loadkeys. That implies a real loadkeys/dumpkeys
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implementation to replace loadkmap/dumpkmap. Plus messing with console font
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loading. Is it worth it, or do we just say "use X"?)
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Individual compilation of applets.
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It would be nice if busybox had the option to compile to individual applets,
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for people who want an alternate implementation less bloated than the gnu
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utils (or simply with less political baggage), but without it being one big
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Turning libbb into a real dll is another possibility, especially if libbb
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could export some of the other library interfaces we've already more or less
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got the code for (like zlib).
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buildroot - Make a "dogfood" option
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Busybox 1.1 will be capable of replacing most gnu packages for real world
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use, such as developing software or in a live CD. It needs wider testing.
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Busybox should now be able to replace bzip2, coreutils, e2fsprogs, file,
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findutils, gawk, grep, inetutils, less, modutils, net-tools, patch, procps,
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sed, shadow, sysklogd, sysvinit, tar, util-linux, and vim. The resulting
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system should be self-hosting (I.E. able to rebuild itself from source
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code). This means it would need (at least) binutils, gcc, and make, or
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It would be a good "eating our own dogfood" test if buildroot had the option
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of using a "make allyesconfig" busybox instead of the all of the above
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packages. Anything that's wrong with the resulting system, we can fix. (It
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would be nice to be able to upgrade busybox to be able to replace bash and
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diffutils as well, but we're not there yet.)
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One example of an existing system that does this already is Firmware Linux:
83
http://www.landley.net/code/firmware
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Busybox should have a sample initramfs build script. This depends on
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shell, mdev, and switch_root.
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Write a mkdep that doesn't segfault if there's a directory it doesn't
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have permission to read, isn't based on manually editing the output of
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lexx and yacc, doesn't make such a mess under include/config, etc.
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Group globals into unions of structures.
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Go through and turn all the global and static variables into structures,
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and have all those structures be in a big union shared between processes,
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so busybox uses less bss. (This is a big win on nommu machines.) See
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sed.c and mdev.c for examples.
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Go through bugs.busybox.net and close out all of that somehow.
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This one's open to everybody, but I'll wind up doing it...
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Bernhard Reutner-Fischer <busybox@busybox.net> suggests to look at these:
106
Cleanup any big users
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Collate BUFSIZ IOBUF_SIZE MY_BUF_SIZE PIPE_PROGRESS_SIZE BUFSIZE PIPESIZE
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make bb_common_bufsiz1 configurable, size wise.
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make pipesize configurable, size wise.
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Use bb_common_bufsiz1 throughout applets!
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Make sure we handle empty files properly:
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From the patch man page:
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you can remove a file by sending out a context diff that compares
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the file to be deleted with an empty file dated the Epoch. The
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file will be removed unless patch is conforming to POSIX and the
122
-E or --remove-empty-files option is not given.
125
Should have simple fuzz factor support to apply patches at an offset which
126
shouldn't take up too much space.
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And while we're at it, a new patch filename quoting format is apparently
129
coming soon: http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
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Architectural issues:
133
bb_close() with fsync()
134
We should have a bb_close() in place of normal close, with a CONFIG_ option
135
to not just check the return value of close() for an error, but fsync().
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Close can't reliably report anything useful because if write() accepted the
137
data then it either went out to the network or it's in cache or a pipe
138
buffer. Either way, there's no guarantee it'll make it to its final
139
destination before close() gets called, so there's no guarantee that any
140
error will be reported.
142
You need to call fsync() if you care about errors that occur after write(),
143
but that can have a big performance impact. So make it a config option.
146
Lots of archivers have the same general infrastructure. The directory
147
traversal code should be factored out, and the guts of each archiver could
148
be some setup code and a series of callbacks for "add this file",
149
"add this directory", "add this symlink" and so on.
151
This could clean up tar and zip, and make it cheaper to add cpio and ar
152
write support, and possibly even cheaply add things like mkisofs or
153
mksquashfs someday, if they become relevant.
156
Several existing applets (sort, vi, less...) read
157
a whole file into memory and act on it. Use open_read_close().
160
We have a CONFIG_BUFFER mechanism that lets us select whether to do memory
161
allocation on the stack or the heap. Unfortunately, we're not using it much.
162
We need to audit our memory allocations and turn a lot of malloc/free calls
163
into RESERVE_CONFIG_BUFFER/RELEASE_CONFIG_BUFFER.
164
For a start, see e.g. make EXTRA_CFLAGS=-Wlarger-than-64
166
And while we're at it, many of the CONFIG_FEATURE_CLEAN_UP #ifdefs will be
167
optimized out by the compiler in the stack allocation case (since there's no
168
free for an alloca()), and this means that various cleanup loops that just
169
call free might also be optimized out by the compiler if written right, so
170
we can yank those #ifdefs too, and generally clean up the code.
173
This is more an unresolved issue than a to-do item. More thought is needed.
175
Normally we rely on exit() to free memory, close files and unmap segments
176
for us. This makes most calls to free(), close(), and unmap() optional in
177
busybox applets that don't intend to run for very long, and optional stuff
178
can be omitted to save size.
180
The idea was raised that we could simulate fork/exit with setjmp/longjmp
181
for _really_ brainless embedded systems, or speed up the standalone shell
182
by not forking. Doing so would require a reliable FEATURE_CLEAN_UP.
183
Unfortunately, this isn't as easy as it sounds.
185
The problem is, lots of things exit(), sometimes unexpectedly (xmalloc())
186
and sometimes reliably (bb_perror_msg_and_die() or show_usage()). This
187
jumps out of the normal flow control and bypasses any cleanup code we
188
put at the end of our applets.
190
It's possible to add hooks to libbb functions like xmalloc() and xopen()
191
to add their entries to a linked list, which could be traversed and
192
freed/closed automatically. (This would need to be able to free just the
193
entries after a checkpoint to be usable for a forkless standalone shell.
194
You don't want to free the shell's own resources.)
196
Right now, FEATURE_CLEAN_UP is more or less a debugging aid, to make things
197
like valgrind happy. It's also documentation of _what_ we're trusting
198
exit() to clean up for us. But new infrastructure to auto-free stuff would
199
render the existing FEATURE_CLEAN_UP code redundant.
201
For right now, exit() handles it just fine.
205
watchdog.c could autodetect the timer duration via:
206
if(!ioctl (fd, WDIOC_GETTIMEOUT, &tmo)) timer_duration = 1 + (tmo / 2);
207
Unfortunately, that needs linux/watchdog.h and that contains unfiltered
208
kernel types on some distros, which breaks the build.
210
use bb_error_msg where appropriate: See
211
egrep "(printf.*\([[:space:]]*(stderr|2)|[^_]write.*\([[:space:]]*(stderr|2))"
213
use bb_perror_msg where appropriate: See
216
possible code duplication ingroup() and is_a_group_member()
218
Move __get_hz() to a better place and (re)use it in route.c, ash.c
221
Alot of duplication that wants cleanup.
223
unify progress_meter. wget, flash_eraseall, pipe_progress, fbsplash, setfiles.
226
(TODO list after discussion 11.05.2009)
229
tc/brctl seem like fairly large things to try and tackle in your timeframe,
230
and i think people have posted attempts in the past. Adding additional
231
options to ip though seems reasonable.
233
* add tests for some applets
235
* implement POSIX utilities and audit them for POSIX conformance. then
236
audit them for GNU conformance. then document all your findings in a new
237
doc/conformance.txt file while perhaps implementing some of the missing
239
you can find the latest POSIX documentation (1003.1-2008) here:
240
http://www.opengroup.org/onlinepubs/9699919799/
241
and the complete list of all utilities that POSIX covers:
242
http://www.opengroup.org/onlinepubs/9699919799/idx/utilities.html
243
The first step would to generate a file/matrix what is already archived
248
* rpcbind (former portmap) or equivalent
249
so that we don't have to use -o nolock on nfs mounts
251
* check IPV6 compliance
253
* generate a mini example using kernel+busybox only (+libc) for example
255
* more support for advanced linux 2.6.x features, see: iotop
256
most likely there is more
1
TODO list for busybox in no particular order
3
* Add in a mini syslogd
4
* Allow tar to create archives with sockets, devices, and other special files
5
* Add in a mini modprobe, insmod, rmmod
7
* Change init so halt, reboot (and poweroff) work with an initrd
added
removed
TODO
