blob: dcf48c2c2cb2cb793f41cf2cd5817299c0ba1dfd [file] [log] [blame]
Glenn L McGrath90d2bff2004-05-01 00:49:49 +00001Busybox TODO
2
Denys Vlasenko91d7ee32010-06-19 22:15:20 +02003Harvest patches from
4http://git.openembedded.org/cgit.cgi/openembedded/tree/recipes/busybox/
Tanguy Pruvot8a6c2c22012-04-28 00:24:09 +02005https://dev.openwrt.org/browser/trunk/package/busybox/patches/
6
Denys Vlasenko91d7ee32010-06-19 22:15:20 +02007
Rob Landleydf4cdaf2006-05-19 20:47:55 +00008Stuff that needs to be done. This is organized by who plans to get around to
9doing it eventually, but that doesn't mean they "own" the item. If you want to
10do one of these bounce an email off the person it's listed under to see if they
11have any suggestions how they plan to go about it, and to minimize conflicts
12between your work and theirs. But otherwise, all of these are fair game.
Glenn L McGrath90d2bff2004-05-01 00:49:49 +000013
Dan Fandrichfe4e23f2009-11-01 04:01:30 +010014Rob Landley suggested this:
15 Implement bb_realpath() that can handle NULL on non-glibc.
Rob Landley0582ee02006-05-29 05:06:06 +000016
Rob Landleydf4cdaf2006-05-19 20:47:55 +000017 sh
Denys Vlasenko1cc4b132009-08-21 00:05:51 +020018 The command shell situation is a mess. We have two different
Rob Landleydf4cdaf2006-05-19 20:47:55 +000019 shells that don't really share any code, and the "standalone shell" doesn't
20 work all that well (especially not in a chroot environment), due to apps not
Denis Vlasenko96702ca2007-11-23 23:28:55 +000021 being reentrant.
Denys Vlasenko62298ab2009-09-07 13:19:17 +020022
Rob Landleydf4cdaf2006-05-19 20:47:55 +000023 Do a SUSv3 audit
24 Look at the full Single Unix Specification version 3 (available online at
25 "http://www.opengroup.org/onlinepubs/009695399/nfindex.html") and
26 figure out which of our apps are compliant, and what we're missing that
27 we might actually care about.
28
29 Even better would be some kind of automated compliance test harness that
30 exercises each command line option and the various corner cases.
Denys Vlasenko62298ab2009-09-07 13:19:17 +020031
Rob Landleydf4cdaf2006-05-19 20:47:55 +000032 Internationalization
33 How much internationalization should we do?
34
35 The low hanging fruit is UTF-8 character set support. We should do this.
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020036 See TODO_unicode file.
Rob Landleydf4cdaf2006-05-19 20:47:55 +000037
38 We also have lots of hardwired english text messages. Consolidating this
39 into some kind of message table not only makes translation easier, but
40 also allows us to consolidate redundant (or close) strings.
41
42 We probably don't want to be bloated with locale support. (Not unless we
43 can cleanly export it from our underlying C library without having to
44 concern ourselves with it directly. Perhaps a few specific things like a
45 config option for "date" are low hanging fruit here?)
46
47 What level should things happen at? How much do we care about
48 internationalizing the text console when X11 and xterms are so much better
49 at it? (There's some infrastructure here we don't implement: The
50 "unicode_start" and "unicode_stop" shell scripts need "vt-is-UTF8" and a
51 --unicode option to loadkeys. That implies a real loadkeys/dumpkeys
52 implementation to replace loadkmap/dumpkmap. Plus messing with console font
53 loading. Is it worth it, or do we just say "use X"?)
54
55 Individual compilation of applets.
56 It would be nice if busybox had the option to compile to individual applets,
57 for people who want an alternate implementation less bloated than the gnu
58 utils (or simply with less political baggage), but without it being one big
59 executable.
60
61 Turning libbb into a real dll is another possibility, especially if libbb
62 could export some of the other library interfaces we've already more or less
63 got the code for (like zlib).
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020064
Rob Landleydf4cdaf2006-05-19 20:47:55 +000065 buildroot - Make a "dogfood" option
66 Busybox 1.1 will be capable of replacing most gnu packages for real world
67 use, such as developing software or in a live CD. It needs wider testing.
68
69 Busybox should now be able to replace bzip2, coreutils, e2fsprogs, file,
70 findutils, gawk, grep, inetutils, less, modutils, net-tools, patch, procps,
71 sed, shadow, sysklogd, sysvinit, tar, util-linux, and vim. The resulting
72 system should be self-hosting (I.E. able to rebuild itself from source
73 code). This means it would need (at least) binutils, gcc, and make, or
74 equivalents.
75
76 It would be a good "eating our own dogfood" test if buildroot had the option
77 of using a "make allyesconfig" busybox instead of the all of the above
78 packages. Anything that's wrong with the resulting system, we can fix. (It
79 would be nice to be able to upgrade busybox to be able to replace bash and
80 diffutils as well, but we're not there yet.)
81
82 One example of an existing system that does this already is Firmware Linux:
83 http://www.landley.net/code/firmware
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020084
Rob Landleydf4cdaf2006-05-19 20:47:55 +000085 initramfs
86 Busybox should have a sample initramfs build script. This depends on
Denys Vlasenko96f064d2010-09-06 10:18:21 +020087 shell, mdev, and switch_root.
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020088
Rob Landley9c0e4f02006-06-30 16:38:09 +000089 mkdep
90 Write a mkdep that doesn't segfault if there's a directory it doesn't
91 have permission to read, isn't based on manually editing the output of
92 lexx and yacc, doesn't make such a mess under include/config, etc.
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020093
Rob Landley9c0e4f02006-06-30 16:38:09 +000094 Group globals into unions of structures.
95 Go through and turn all the global and static variables into structures,
96 and have all those structures be in a big union shared between processes,
97 so busybox uses less bss. (This is a big win on nommu machines.) See
98 sed.c and mdev.c for examples.
Denys Vlasenko91d7ee32010-06-19 22:15:20 +020099
Rob Landley9c0e4f02006-06-30 16:38:09 +0000100 Go through bugs.busybox.net and close out all of that somehow.
101 This one's open to everybody, but I'll wind up doing it...
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000102
Bernhard Reutner-Fischer6c4dade2008-09-25 12:13:34 +0000103Bernhard Reutner-Fischer <busybox@busybox.net> suggests to look at these:
Rob Landley0582ee02006-05-29 05:06:06 +0000104 New debug options:
105 -Wlarger-than-127
Bernhard Reutner-Fischer05592ac2006-09-21 22:58:38 +0000106 Cleanup any big users
Rob Landley0582ee02006-05-29 05:06:06 +0000107 Collate BUFSIZ IOBUF_SIZE MY_BUF_SIZE PIPE_PROGRESS_SIZE BUFSIZE PIPESIZE
Bernhard Reutner-Fischer05592ac2006-09-21 22:58:38 +0000108 make bb_common_bufsiz1 configurable, size wise.
109 make pipesize configurable, size wise.
110 Use bb_common_bufsiz1 throughout applets!
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000111
112As yet unclaimed:
113
Mike Frysingerb38673f2006-02-02 01:41:53 +0000114----
Rob Landleyf4bb2122005-01-24 06:56:24 +0000115diff
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000116 Make sure we handle empty files properly:
Rob Landley8bcc6e92006-01-09 00:54:46 +0000117 From the patch man page:
118
Mike Frysinger0b7dfb52006-07-27 03:42:30 +0000119 you can remove a file by sending out a context diff that compares
120 the file to be deleted with an empty file dated the Epoch. The
121 file will be removed unless patch is conforming to POSIX and the
122 -E or --remove-empty-files option is not given.
Rob Landleyf4bb2122005-01-24 06:56:24 +0000123---
124patch
Rob Landleyc9c959c2005-10-27 00:57:50 +0000125 Should have simple fuzz factor support to apply patches at an offset which
Rob Landley078bacf2005-09-01 03:02:23 +0000126 shouldn't take up too much space.
Rob Landleyc9c959c2005-10-27 00:57:50 +0000127
128 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
Rob Landleyf4bb2122005-01-24 06:56:24 +0000130
131Architectural issues:
132
Rob Landley7b7c99c2005-11-04 20:45:54 +0000133bb_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().
136 Close can't reliably report anything useful because if write() accepted the
Rob Landley8bcc6e92006-01-09 00:54:46 +0000137 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.
141
Rob Landley7b7c99c2005-11-04 20:45:54 +0000142 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.
144---
Rob Landleyf4bb2122005-01-24 06:56:24 +0000145Unify archivers
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.
150
151 This could clean up tar and zip, and make it cheaper to add cpio and ar
Rob Landley8bcc6e92006-01-09 00:54:46 +0000152 write support, and possibly even cheaply add things like mkisofs or
153 mksquashfs someday, if they become relevant.
Rob Landleyf4bb2122005-01-24 06:56:24 +0000154---
155Text buffer support.
Rob Landleyc58fd152005-10-25 20:22:50 +0000156 Several existing applets (sort, vi, less...) read
Bernhard Reutner-Fischere455f6e2009-02-18 14:05:54 +0000157 a whole file into memory and act on it. Use open_read_close().
Rob Landleyf4bb2122005-01-24 06:56:24 +0000158---
Rob Landley958fa2a2005-06-11 22:10:42 +0000159Memory Allocation
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.
Rob Landley1fa4a942006-06-22 22:05:00 +0000164 For a start, see e.g. make EXTRA_CFLAGS=-Wlarger-than-64
Rob Landleya8821262005-09-16 14:58:55 +0000165
Rob Landley958fa2a2005-06-11 22:10:42 +0000166 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.
Rob Landleya8821262005-09-16 14:58:55 +0000171---
Rob Landleya8821262005-09-16 14:58:55 +0000172FEATURE_CLEAN_UP
173 This is more an unresolved issue than a to-do item. More thought is needed.
174
Bernhard Reutner-Fischer8517d6f2009-03-05 17:27:39 +0000175 Normally we rely on exit() to free memory, close files and unmap segments
Rob Landleya8821262005-09-16 14:58:55 +0000176 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.
179
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.
184
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.
189
Bernhard Reutner-Fischer8c1eda52006-08-28 23:39:36 +0000190 It's possible to add hooks to libbb functions like xmalloc() and xopen()
Rob Landleya8821262005-09-16 14:58:55 +0000191 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.)
195
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.
200
201 For right now, exit() handles it just fine.
Rob Landley8bcc6e92006-01-09 00:54:46 +0000202
203
Rob Landley8bcc6e92006-01-09 00:54:46 +0000204Minor stuff:
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.
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000209---
Bernhard Reutner-Fischer395010b2006-06-04 15:37:59 +0000210 use bb_error_msg where appropriate: See
211 egrep "(printf.*\([[:space:]]*(stderr|2)|[^_]write.*\([[:space:]]*(stderr|2))"
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000212---
Bernhard Reutner-Fischer395010b2006-06-04 15:37:59 +0000213 use bb_perror_msg where appropriate: See
214 egrep "[^_]perror"
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000215---
Bernhard Reutner-Fischer213cc002006-06-04 17:58:19 +0000216 possible code duplication ingroup() and is_a_group_member()
217---
Denys Vlasenko1cc4b132009-08-21 00:05:51 +0200218 Move __get_hz() to a better place and (re)use it in route.c, ash.c
Bernhard Reutner-Fischere02706f2006-07-02 10:33:10 +0000219---
Bernhard Reutner-Fischerc2f0de52008-01-14 14:32:56 +0000220 See grep -r strtod
221 Alot of duplication that wants cleanup.
222---
Bernhard Reutner-Fischere455f6e2009-02-18 14:05:54 +0000223 unify progress_meter. wget, flash_eraseall, pipe_progress, fbsplash, setfiles.
Bernhard Reutner-Fischerae0045e2009-09-17 18:57:21 +0200224---
Denys Vlasenko91d7ee32010-06-19 22:15:20 +0200225 support start-stop-daemon -d <chdir-path>
Bernhard Reutner-Fischer2677cf12006-01-13 08:46:39 +0000226---
Bernhard Reutner-Fischer34fc71f2006-04-12 18:50:19 +0000227vdprintf() -> similar sized functionality
228---
Denys Vlasenko318a8e52009-05-13 02:18:43 +0200229
230(TODO list after discussion 11.05.2009)
231
232* shrink tc/brctl/ip
233 tc/brctl seem like fairly large things to try and tackle in your timeframe,
Bernhard Reutner-Fischerca4f8d52009-07-03 01:06:15 +0200234 and i think people have posted attempts in the past. Adding additional
Denys Vlasenko318a8e52009-05-13 02:18:43 +0200235 options to ip though seems reasonable.
236
237* add tests for some applets
238
239* implement POSIX utilities and audit them for POSIX conformance. then
240 audit them for GNU conformance. then document all your findings in a new
241 doc/conformance.txt file while perhaps implementing some of the missing
242 features.
243 you can find the latest POSIX documentation (1003.1-2008) here:
244 http://www.opengroup.org/onlinepubs/9699919799/
245 and the complete list of all utilities that POSIX covers:
246 http://www.opengroup.org/onlinepubs/9699919799/idx/utilities.html
247 The first step would to generate a file/matrix what is already archived
248 (also IPV6)
249
Denys Vlasenko318a8e52009-05-13 02:18:43 +0200250* implement 'at'
251
252* rpcbind (former portmap) or equivalent
253 so that we don't have to use -o nolock on nfs mounts
254
255* check IPV6 compliance
256
257* generate a mini example using kernel+busybox only (+libc) for example
258
259* more support for advanced linux 2.6.x features, see: iotop
260 most likely there is more
261
262* even more support for statistics: mpstat, iostat, powertop....