blob: f42c83ff8dd365169a77c38ed6efa5b8a5d6fa35 [file] [log] [blame]
Glenn L McGrath90d2bff2004-05-01 00:49:49 +00001Busybox TODO
2
Rob Landleydf4cdaf2006-05-19 20:47:55 +00003Stuff that needs to be done. This is organized by who plans to get around to
4doing it eventually, but that doesn't mean they "own" the item. If you want to
5do one of these bounce an email off the person it's listed under to see if they
6have any suggestions how they plan to go about it, and to minimize conflicts
7between your work and theirs. But otherwise, all of these are fair game.
Glenn L McGrath90d2bff2004-05-01 00:49:49 +00008
Rob Landleydf4cdaf2006-05-19 20:47:55 +00009Rob Landley <rob@landley.net>:
Rob Landley4b146e62006-05-30 18:31:37 +000010 Add BB_NOMMU to platform.h and migrate __uClinux__ tests to that.
11 #if defined __UCLIBC__ && !defined __ARCH_USE_MMU__
Rob Landley0582ee02006-05-29 05:06:06 +000012 Add a libbb/platform.c
13 Implement fdprintf() for platforms that haven't got one.
14 Implement bb_realpath() that can handle NULL on non-glibc.
15 Cleanup bb_asprintf()
16
Rob Landleydf4cdaf2006-05-19 20:47:55 +000017 Migrate calloc() and bb_calloc() occurrences to bb_xzalloc().
18 Remove obsolete _() wrapper crud for internationalization we don't do.
19 Figure out where we need utf8 support, and add it.
20
21 sh
22 The command shell situation is a big mess. We have three or four different
23 shells that don't really share any code, and the "standalone shell" doesn't
24 work all that well (especially not in a chroot environment), due to apps not
25 being reentrant. I'm writing a new shell (bbsh) to unify the various
26 shells and configurably add the minimal set of bash features people
27 actually use. The hardest part is it has to configure down as small as
28 lash while providing lash's features. The rest is easy in comparison.
29 bzip2
30 Compression-side support.
31 init
Bernhard Reutner-Fischer0da069d2006-05-29 12:54:16 +000032 General cleanup (should use ENABLE_FEATURE_INIT_SYSLOG and ENABLE_FEATURE_INIT_DEBUG).
Ned Ludd5df6d9f2006-06-30 21:48:38 +000033 depmod
34 busybox lacks a way to update module deps when running from firmware without the
35 use of the depmod.pl (perl is to bloated for most embedded setups) and or orig
36 modutils. The orig depmod is rather pointless to have to add to a firmware image
37 in when we already have a insmod/rmmod and friends.
Rob Landleydf4cdaf2006-05-19 20:47:55 +000038 Unify base64 handling.
39 There's base64 encoding and decoding going on in:
40 networking/wget.c:base64enc()
41 coreutils/uudecode.c:read_base64()
42 coreutils/uuencode.c:tbl_base64[]
43 networking/httpd.c:decodeBase64()
44 And probably elsewhere. That needs to be unified into libbb functions.
45 Do a SUSv3 audit
46 Look at the full Single Unix Specification version 3 (available online at
47 "http://www.opengroup.org/onlinepubs/009695399/nfindex.html") and
48 figure out which of our apps are compliant, and what we're missing that
49 we might actually care about.
50
51 Even better would be some kind of automated compliance test harness that
52 exercises each command line option and the various corner cases.
53 Internationalization
54 How much internationalization should we do?
55
56 The low hanging fruit is UTF-8 character set support. We should do this.
57 (Vodz pointed out the shell's cmdedit as needing work here. What else?)
58
59 We also have lots of hardwired english text messages. Consolidating this
60 into some kind of message table not only makes translation easier, but
61 also allows us to consolidate redundant (or close) strings.
62
63 We probably don't want to be bloated with locale support. (Not unless we
64 can cleanly export it from our underlying C library without having to
65 concern ourselves with it directly. Perhaps a few specific things like a
66 config option for "date" are low hanging fruit here?)
67
68 What level should things happen at? How much do we care about
69 internationalizing the text console when X11 and xterms are so much better
70 at it? (There's some infrastructure here we don't implement: The
71 "unicode_start" and "unicode_stop" shell scripts need "vt-is-UTF8" and a
72 --unicode option to loadkeys. That implies a real loadkeys/dumpkeys
73 implementation to replace loadkmap/dumpkmap. Plus messing with console font
74 loading. Is it worth it, or do we just say "use X"?)
75
76 Individual compilation of applets.
77 It would be nice if busybox had the option to compile to individual applets,
78 for people who want an alternate implementation less bloated than the gnu
79 utils (or simply with less political baggage), but without it being one big
80 executable.
81
82 Turning libbb into a real dll is another possibility, especially if libbb
83 could export some of the other library interfaces we've already more or less
84 got the code for (like zlib).
85 buildroot - Make a "dogfood" option
86 Busybox 1.1 will be capable of replacing most gnu packages for real world
87 use, such as developing software or in a live CD. It needs wider testing.
88
89 Busybox should now be able to replace bzip2, coreutils, e2fsprogs, file,
90 findutils, gawk, grep, inetutils, less, modutils, net-tools, patch, procps,
91 sed, shadow, sysklogd, sysvinit, tar, util-linux, and vim. The resulting
92 system should be self-hosting (I.E. able to rebuild itself from source
93 code). This means it would need (at least) binutils, gcc, and make, or
94 equivalents.
95
96 It would be a good "eating our own dogfood" test if buildroot had the option
97 of using a "make allyesconfig" busybox instead of the all of the above
98 packages. Anything that's wrong with the resulting system, we can fix. (It
99 would be nice to be able to upgrade busybox to be able to replace bash and
100 diffutils as well, but we're not there yet.)
101
102 One example of an existing system that does this already is Firmware Linux:
103 http://www.landley.net/code/firmware
104 initramfs
105 Busybox should have a sample initramfs build script. This depends on
106 bbsh, mdev, and switch_root.
Rob Landley9c0e4f02006-06-30 16:38:09 +0000107 mkdep
108 Write a mkdep that doesn't segfault if there's a directory it doesn't
109 have permission to read, isn't based on manually editing the output of
110 lexx and yacc, doesn't make such a mess under include/config, etc.
111 Group globals into unions of structures.
112 Go through and turn all the global and static variables into structures,
113 and have all those structures be in a big union shared between processes,
114 so busybox uses less bss. (This is a big win on nommu machines.) See
115 sed.c and mdev.c for examples.
116 Go through bugs.busybox.net and close out all of that somehow.
117 This one's open to everybody, but I'll wind up doing it...
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000118
119
120Bernhard Fischer <rep.nop@anon.at>:
121 Makefile stuff:
122 make -j is broken, -j1 is forced atm
Rob Landley0582ee02006-05-29 05:06:06 +0000123 New debug options:
124 -Wlarger-than-127
125 Collate BUFSIZ IOBUF_SIZE MY_BUF_SIZE PIPE_PROGRESS_SIZE BUFSIZE PIPESIZE
126 Use bb_common_bufsiz1?
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000127
128As yet unclaimed:
129
Mike Frysingerb38673f2006-02-02 01:41:53 +0000130----
Rob Landleyf4bb2122005-01-24 06:56:24 +0000131find
Rob Landleyc58fd152005-10-25 20:22:50 +0000132 doesn't understand (), lots of susv3 stuff.
Rob Landleyf4bb2122005-01-24 06:56:24 +0000133----
Rob Landleyf4bb2122005-01-24 06:56:24 +0000134diff
Rob Landleydf4cdaf2006-05-19 20:47:55 +0000135 Make sure we handle empty files properly:
Rob Landley8bcc6e92006-01-09 00:54:46 +0000136 From the patch man page:
137
138   you can remove a file by sending out a context diff that compares
139   the file to be deleted with an empty file dated the Epoch.  The
140   file will be removed unless patch is conforming to POSIX and the
141   -E or --remove-empty-files option is not given.
Rob Landleyf4bb2122005-01-24 06:56:24 +0000142---
143patch
Rob Landleyc9c959c2005-10-27 00:57:50 +0000144 Should have simple fuzz factor support to apply patches at an offset which
Rob Landley078bacf2005-09-01 03:02:23 +0000145 shouldn't take up too much space.
Rob Landleyc9c959c2005-10-27 00:57:50 +0000146
147 And while we're at it, a new patch filename quoting format is apparently
148 coming soon: http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
Rob Landleyf4bb2122005-01-24 06:56:24 +0000149---
150man
151 It would be nice to have a man command. Not one that handles troff or
152 anything, just one that can handle preformatted ascii man pages, possibly
153 compressed. This could probably be a script in the extras directory that
Rob Landleyc58fd152005-10-25 20:22:50 +0000154 calls cat/zcat/bzcat | less
Rob Landley8bcc6e92006-01-09 00:54:46 +0000155
156 (How doclifter might work into this is anybody's guess.)
Rob Landleyf4bb2122005-01-24 06:56:24 +0000157---
Rob Landley8bcc6e92006-01-09 00:54:46 +0000158ar
159 Write support?
160---
Bernhard Reutner-Fischerfc477f42006-04-26 19:40:15 +0000161crond
162 turn FEATURE_DEBUG_OPT into ENABLE_FEATURE_CROND_DEBUG_OPT
Rob Landleyf4bb2122005-01-24 06:56:24 +0000163
164Architectural issues:
165
Rob Landley7b7c99c2005-11-04 20:45:54 +0000166bb_close() with fsync()
167 We should have a bb_close() in place of normal close, with a CONFIG_ option
168 to not just check the return value of close() for an error, but fsync().
169 Close can't reliably report anything useful because if write() accepted the
Rob Landley8bcc6e92006-01-09 00:54:46 +0000170 data then it either went out to the network or it's in cache or a pipe
171 buffer. Either way, there's no guarantee it'll make it to its final
172 destination before close() gets called, so there's no guarantee that any
173 error will be reported.
174
Rob Landley7b7c99c2005-11-04 20:45:54 +0000175 You need to call fsync() if you care about errors that occur after write(),
176 but that can have a big performance impact. So make it a config option.
177---
Rob Landleyf4bb2122005-01-24 06:56:24 +0000178Unify archivers
179 Lots of archivers have the same general infrastructure. The directory
180 traversal code should be factored out, and the guts of each archiver could
181 be some setup code and a series of callbacks for "add this file",
182 "add this directory", "add this symlink" and so on.
183
184 This could clean up tar and zip, and make it cheaper to add cpio and ar
Rob Landley8bcc6e92006-01-09 00:54:46 +0000185 write support, and possibly even cheaply add things like mkisofs or
186 mksquashfs someday, if they become relevant.
Rob Landleyf4bb2122005-01-24 06:56:24 +0000187---
188Text buffer support.
Rob Landleyc58fd152005-10-25 20:22:50 +0000189 Several existing applets (sort, vi, less...) read
Rob Landleyf4bb2122005-01-24 06:56:24 +0000190 a whole file into memory and act on it. There might be an opportunity
191 for shared code in there that could be moved into libbb...
192---
Rob Landley958fa2a2005-06-11 22:10:42 +0000193Memory Allocation
194 We have a CONFIG_BUFFER mechanism that lets us select whether to do memory
195 allocation on the stack or the heap. Unfortunately, we're not using it much.
196 We need to audit our memory allocations and turn a lot of malloc/free calls
197 into RESERVE_CONFIG_BUFFER/RELEASE_CONFIG_BUFFER.
Rob Landley1fa4a942006-06-22 22:05:00 +0000198 For a start, see e.g. make EXTRA_CFLAGS=-Wlarger-than-64
Rob Landleya8821262005-09-16 14:58:55 +0000199
Rob Landley958fa2a2005-06-11 22:10:42 +0000200 And while we're at it, many of the CONFIG_FEATURE_CLEAN_UP #ifdefs will be
201 optimized out by the compiler in the stack allocation case (since there's no
202 free for an alloca()), and this means that various cleanup loops that just
203 call free might also be optimized out by the compiler if written right, so
204 we can yank those #ifdefs too, and generally clean up the code.
Rob Landleya8821262005-09-16 14:58:55 +0000205---
206Switch CONFIG_SYMBOLS to ENABLE_SYMBOLS
207
208 In busybox 1.0 and earlier, configuration was done by CONFIG_SYMBOLS
209 that were either defined or undefined to indicate whether the symbol was
210 selected in the .config file. They were used with #ifdefs, ala:
211
212 #ifdef CONFIG_SYMBOL
213 if (other_test) {
214 do_code();
215 }
216 #endif
217
218 In 1.1, we have new ENABLE_SYMBOLS which are always defined (as 0 or 1),
219 meaning you can still use them for preprocessor tests by replacing
220 "#ifdef CONFIG_SYMBOL" with "#if ENABLE_SYMBOL". But more importantly, we
221 can use them as a true or false test in normal C code:
222
223 if (ENABLE_SYMBOL && other_test) {
224 do_code();
225 }
226
227 (Optimizing away if() statements that resolve to a constant value
228 is known as "dead code elimination", an optimization so old and simple that
229 Turbo Pascal for DOS did it twenty years ago. Even modern mini-compilers
230 like the Tiny C Compiler (tcc) and the Small Device C Compiler (SDCC)
231 perform dead code elimination.)
232
233 Right now, busybox.h is #including both "config.h" (defining the
234 CONFIG_SYMBOLS) and "bb_config.h" (defining the ENABLE_SYMBOLS). At some
235 point in the future, it would be nice to wean ourselves off of the
236 CONFIG versions. (Among other things, some defective build environments
237 leak the Linux kernel's CONFIG_SYMBOLS into the system's standard #include
238 files. We've experienced collisions before.)
239---
240FEATURE_CLEAN_UP
241 This is more an unresolved issue than a to-do item. More thought is needed.
242
243 Normally we rely on exit() to free memory, close files, and unmap segments
244 for us. This makes most calls to free(), close(), and unmap() optional in
245 busybox applets that don't intend to run for very long, and optional stuff
246 can be omitted to save size.
247
248 The idea was raised that we could simulate fork/exit with setjmp/longjmp
249 for _really_ brainless embedded systems, or speed up the standalone shell
250 by not forking. Doing so would require a reliable FEATURE_CLEAN_UP.
251 Unfortunately, this isn't as easy as it sounds.
252
253 The problem is, lots of things exit(), sometimes unexpectedly (xmalloc())
254 and sometimes reliably (bb_perror_msg_and_die() or show_usage()). This
255 jumps out of the normal flow control and bypasses any cleanup code we
256 put at the end of our applets.
257
258 It's possible to add hooks to libbb functions like xmalloc() and bb_xopen()
259 to add their entries to a linked list, which could be traversed and
260 freed/closed automatically. (This would need to be able to free just the
261 entries after a checkpoint to be usable for a forkless standalone shell.
262 You don't want to free the shell's own resources.)
263
264 Right now, FEATURE_CLEAN_UP is more or less a debugging aid, to make things
265 like valgrind happy. It's also documentation of _what_ we're trusting
266 exit() to clean up for us. But new infrastructure to auto-free stuff would
267 render the existing FEATURE_CLEAN_UP code redundant.
268
269 For right now, exit() handles it just fine.
Rob Landley8bcc6e92006-01-09 00:54:46 +0000270
271
272
273Minor stuff:
274 watchdog.c could autodetect the timer duration via:
275 if(!ioctl (fd, WDIOC_GETTIMEOUT, &tmo)) timer_duration = 1 + (tmo / 2);
276 Unfortunately, that needs linux/watchdog.h and that contains unfiltered
277 kernel types on some distros, which breaks the build.
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000278---
Bernhard Reutner-Fischer395010b2006-06-04 15:37:59 +0000279 use bb_error_msg where appropriate: See
280 egrep "(printf.*\([[:space:]]*(stderr|2)|[^_]write.*\([[:space:]]*(stderr|2))"
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000281---
Bernhard Reutner-Fischer395010b2006-06-04 15:37:59 +0000282 use bb_perror_msg where appropriate: See
283 egrep "[^_]perror"
Bernhard Reutner-Fischer863073d2006-06-04 16:05:02 +0000284---
285 Remove superfluous fmt occurances: e.g.
286 fprintf(stderr, "%s: %s not found\n", "unalias", *argptr);
287 -> fprintf(stderr, "unalias: %s not found\n", *argptr);
288---
Bernhard Reutner-Fischer213cc002006-06-04 17:58:19 +0000289 possible code duplication ingroup() and is_a_group_member()
290---
Bernhard Reutner-Fischerbc291dc2006-06-05 16:00:12 +0000291 unify itoa: netstat.c, hush.c, lash.c, msh.c
292 Put one single, robust version into e.g. safe_strtol.c
293---
Bernhard Reutner-Fischere02706f2006-07-02 10:33:10 +0000294 Move __get_hz() to a better place and (re)use it in route.c, ash.c, msh.c
295---
Bernhard Reutner-Fischer395010b2006-06-04 15:37:59 +0000296
Bernhard Reutner-Fischer2677cf12006-01-13 08:46:39 +0000297
298Code cleanup:
299
300Replace deprecated functions.
301
302bzero() -> memset()
303---
304sigblock(), siggetmask(), sigsetmask(), sigmask() -> sigprocmask et al
305---
Bernhard Reutner-Fischer34fc71f2006-04-12 18:50:19 +0000306vdprintf() -> similar sized functionality
307---
Bernhard Reutner-Fischer2677cf12006-01-13 08:46:39 +0000308