Denis Vlasenko | e471275 | 2007-04-14 15:08:41 +0000 | [diff] [blame] | 1 | Various bits of what is known about busybox shells, in no particular order. |
| 2 | |
Denis Vlasenko | d67cef2 | 2007-06-13 06:47:47 +0000 | [diff] [blame^] | 3 | 2007-06-13 |
| 4 | hush: exec <"$1" doesn't do parameter subst |
| 5 | |
Denis Vlasenko | 163a855 | 2007-05-24 13:52:46 +0000 | [diff] [blame] | 6 | 2007-05-24 |
Denis Vlasenko | d76c049 | 2007-05-25 02:16:25 +0000 | [diff] [blame] | 7 | hush: environment-related memory leak plugged, with net code size |
| 8 | decrease. |
| 9 | |
| 10 | 2007-05-24 |
Denis Vlasenko | 163a855 | 2007-05-24 13:52:46 +0000 | [diff] [blame] | 11 | hush: '( echo ${name )' will show syntax error message, but prompt |
| 12 | doesn't return (need to press <enter>). Pressing Ctrl-C, <enter>, |
| 13 | '( echo ${name )' again, Ctrl-C segfaults. |
| 14 | |
Denis Vlasenko | 8805eeb | 2007-05-21 10:19:48 +0000 | [diff] [blame] | 15 | 2007-05-21 |
| 16 | hush: environment cannot be handled by libc routines as they are leaky |
| 17 | (by API design and thus unfixable): hush will leak memory in this script, |
| 18 | bash does not: |
| 19 | pid=$$ |
| 20 | while true; do |
| 21 | unset t; |
| 22 | t=111111111111111111111111111111111111111111111111111111111111111111111111 |
| 23 | export t |
| 24 | ps -o vsz,pid,comm | grep " $pid " |
| 25 | done |
| 26 | The fix is to not use setenv/putenv/unsetenv but manipulate env ourself. TODO. |
| 27 | hush: meanwhile, first three command subst bugs mentioned below are fixed. :) |
| 28 | |
| 29 | 2007-05-06 |
Denis Vlasenko | 21f0d4c | 2007-05-06 14:15:42 +0000 | [diff] [blame] | 30 | hush: more bugs spotted. Comparison with bash: |
| 31 | bash-3.2# echo "TEST`date;echo;echo`BEST" |
| 32 | TESTSun May 6 09:21:05 CEST 2007BEST [we dont strip eols] |
| 33 | bash-3.2# echo "TEST`echo '$(echo ZZ)'`BEST" |
| 34 | TEST$(echo ZZ)BEST [we execute inner echo] |
| 35 | bash-3.2# echo "TEST`echo "'"`BEST" |
| 36 | TEST'BEST [we totally mess up this one] |
| 37 | bash-3.2# echo `sleep 5` |
| 38 | [Ctrl-C should work, Ctrl-Z should do nothing][we totally mess up this one] |
| 39 | bash-3.2# if true; then |
| 40 | > [Ctrl-C] |
| 41 | bash-3.2# [we re-issue "> "] |
| 42 | bash-3.2# if echo `sleep 5`; then |
| 43 | > true; fi [we execute sleep before "> "] |
| 44 | |
Denis Vlasenko | ac0e5ab | 2007-05-04 21:37:27 +0000 | [diff] [blame] | 45 | 2007-05-04 |
Denis Vlasenko | 21f0d4c | 2007-05-06 14:15:42 +0000 | [diff] [blame] | 46 | hush: made ctrl-Z/C work correctly for "while true; do true; done" |
| 47 | (namely, it backgrounds/interrupts entire "while") |
Denis Vlasenko | ac0e5ab | 2007-05-04 21:37:27 +0000 | [diff] [blame] | 48 | |
Denis Vlasenko | e725bfe | 2007-05-03 22:45:39 +0000 | [diff] [blame] | 49 | 2007-05-03 |
Denis Vlasenko | 3349fc4 | 2007-05-04 14:54:36 +0000 | [diff] [blame] | 50 | hush: new bug spotted: Ctrl-C on "while true; do true; done" doesn't |
| 51 | work right: |
| 52 | # while true; do true; done |
| 53 | [1] 0 true <-- pressing Ctrl-C several times... |
| 54 | [2] 0 true |
| 55 | [3] 0 true |
| 56 | Segmentation fault |
Denis Vlasenko | 400c5b6 | 2007-05-04 13:07:27 +0000 | [diff] [blame] | 57 | |
| 58 | 2007-05-03 |
Denis Vlasenko | e725bfe | 2007-05-03 22:45:39 +0000 | [diff] [blame] | 59 | hush: update on "sleep 1 | exit 3; echo $?" bug. |
| 60 | parse_stream_outer() repeatedly calls parse_stream(). |
| 61 | parse_stream() is now fixed to stop on ';' in this example, |
| 62 | fixing it (parse_stream_outer() will call parse_stream() 1st time, |
| 63 | execute the parse tree, call parse_stream() 2nd time and execute the tree). |
| 64 | But it's not the end of story. |
| 65 | In more complex situations we _must_ parse way farther before executing. |
| 66 | Example #2: "{ sleep 1 | exit 3; echo $?; ...few_lines... } >file". |
| 67 | Because of redirection, we cannot execute 1st pipe before we parse it all. |
| 68 | We probably need to learn to store $var expressions in parse tree. |
| 69 | Debug printing of parse tree would be nice too. |
| 70 | |
Denis Vlasenko | 08c8c1d | 2007-04-28 22:39:02 +0000 | [diff] [blame] | 71 | 2007-04-28 |
| 72 | hush: Ctrl-C and Ctrl-Z for single NOFORK commands are working. |
| 73 | Memory and other resource leaks (opendir) are not addressed |
| 74 | (testcase is "rm -i" interrupted by ctrl-c). |
| 75 | |
Denis Vlasenko | 52881e9 | 2007-04-21 13:42:52 +0000 | [diff] [blame] | 76 | 2007-04-21 |
Denis Vlasenko | 1359da6 | 2007-04-21 23:27:30 +0000 | [diff] [blame] | 77 | hush: "sleep 5 | sleep 6" + Ctrl-Z + fg seems to work. |
| 78 | "rm -i" + Ctrl-C, "sleep 5" + Ctrl-Z still doesn't work |
| 79 | for SH_STANDALONE case :( |
| 80 | |
| 81 | 2007-04-21 |
Denis Vlasenko | 52881e9 | 2007-04-21 13:42:52 +0000 | [diff] [blame] | 82 | hush: fixed non-backgrounding of "sleep 1 &" and totally broken |
| 83 | "sleep 1 | sleep 2 &". Noticed a bug where successive jobs |
| 84 | get numbers 1,2,3 even when job #1 has exited before job# 2 is started. |
| 85 | (bash reuses #1 in this case) |
| 86 | |
| 87 | 2007-04-21 |
Denis Vlasenko | 2f1bb36 | 2007-04-21 10:01:14 +0000 | [diff] [blame] | 88 | hush: "sleep 1 | exit 3; echo $?" prints 0 because $? is substituted |
| 89 | _before_ pipe gets executed!! run_list_real() already has "pipe;echo" |
| 90 | parsed and handed to it for execution, so it sees "pipe"; "echo 0". |
| 91 | |
Denis Vlasenko | 54e7ffb | 2007-04-21 00:03:36 +0000 | [diff] [blame] | 92 | 2007-04-21 |
| 93 | hush: removed setsid() and made job control sort-of-sometimes-work. |
| 94 | Ctrl-C in "rm -i" works now except for SH_STANDALONE case. |
| 95 | "sleep 1 | exit 3" + "echo $?" works, "sleep 1 | exit 3; echo $?" |
| 96 | shows exitcode 0 (should be 3). "sleep 1 | sleep 2 &" fails horribly. |
| 97 | |
Denis Vlasenko | e471275 | 2007-04-14 15:08:41 +0000 | [diff] [blame] | 98 | 2007-04-14 |
| 99 | lash, hush: both do setsid() and as a result don't have ctty! |
| 100 | Ctrl-C doesn't work for any child (try rm -i), etc... |
| 101 | lash: bare ">file" doesn't create a file (hush works) |