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path: root/libbb/appletlib.c
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2021-02-18libbb: fix '--help' handling in FEATURE_SH_NOFORK=yDenys Vlasenko
Most BusyBox applets respond to the '--help' option by printing a usage message. This is normally handled by busybox_main() so applet main routines don't have support for '--help'. In standalone shell mode with FEATURE_SH_NOFORK enabled nofork applets are invoked directly, bypassing busybox_main(). This results in inconsistent handling of '--help': - applets which call getopt() report "unrecognized option '--help'" and print help anyway; - realpath says "--help: No such file or directory" and doesn't print help; - usleep says "invalid number '--help'" and doesn't print help. Avoid inconsistency by checking for '--help' in run_nofork_applet(). Bug found by Ron Yorston. function old new delta show_usage_if_dash_dash_help - 70 +70 run_nofork_applet 347 362 +15 run_applet_no_and_exit 432 365 -67 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/1 up/down: 85/-67) Total: 18 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-02-02libbb: code shrink and speed up find_applet_by_name()Ron Yorston
find_applet_by_name() determines the appropriate range of applet indices to check for the given name and performs a linear search in applet_names[]. Revise the code so the index of the upper bound of the range, 'max', isn't calculated. Instead check the value of the first non-matching character to see if we've reached the end of the range. This new code speeds up the time to find a valid applet name by 6% and halves the time to detect that a given name is invalid. The average time to detect an invalid name is now the same as for a valid one. function old new delta find_applet_by_name 155 133 -22 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-22) Total: -22 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-10-01libbb: do not open-code __errno_location() callDenys Vlasenko
Thanks dalias! Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-10-01libbb: extend "errno pointer" trick to other than __GLIBC__Denys Vlasenko
Savings on musl: function old new delta resume_main 582 614 +32 lbb_prepare - 20 +20 seq_main 432 449 +17 fgetsetversion 74 88 +14 ... script_main 1207 1180 -27 close_silently 28 - -28 shell_builtin_ulimit 655 626 -29 lineedit_read_key 280 247 -33 ------------------------------------------------------------------------------ (add/remove: 2/1 grow/shrink: 25/123 up/down: 182/-882) Total: -700 bytes text data bss dec hex filename 1005858 551 5676 1012085 f7175 busybox_old 1005136 551 5680 1011367 f6ea7 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-06-24nologin: make it possible to build it as single appletDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-10-25clang/llvm 9 fix - do not eliminate a store to a fake "const"Denys Vlasenko
This is *much* better (9 kbytes better) than dropping "*const" optimization trick. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-07-02libbb: reduce the overhead of single parameter bb_error_msg() callsJames Byrne
Back in 2007, commit 0c97c9d43707 ("'simple' error message functions by Loic Grenie") introduced bb_simple_perror_msg() to allow for a lower overhead call to bb_perror_msg() when only a string was being printed with no parameters. This saves space for some CPU architectures because it avoids the overhead of a call to a variadic function. However there has never been a simple version of bb_error_msg(), and since 2007 many new calls to bb_perror_msg() have been added that only take a single parameter and so could have been using bb_simple_perror_message(). This changeset introduces 'simple' versions of bb_info_msg(), bb_error_msg(), bb_error_msg_and_die(), bb_herror_msg() and bb_herror_msg_and_die(), and replaces all calls that only take a single parameter, or use something like ("%s", arg), with calls to the corresponding 'simple' version. Since it is likely that single parameter calls to the variadic functions may be accidentally reintroduced in the future a new debugging config option WARN_SIMPLE_MSG has been introduced. This uses some macro magic which will cause any such calls to generate a warning, but this is turned off by default to avoid use of the unpleasant macros in normal circumstances. This is a large changeset due to the number of calls that have been replaced. The only files that contain changes other than simple substitution of function calls are libbb.h, libbb/herror_msg.c, libbb/verror_msg.c and libbb/xfuncs_printf.c. In miscutils/devfsd.c, networking/udhcp/common.h and util-linux/mdev.c additonal macros have been added for logging so that single parameter and multiple parameter logging variants exist. The amount of space saved varies considerably by architecture, and was found to be as follows (for 'defconfig' using GCC 7.4): Arm: -92 bytes MIPS: -52 bytes PPC: -1836 bytes x86_64: -938 bytes Note that for the MIPS architecture only an exception had to be made disabling the 'simple' calls for 'udhcp' (in networking/udhcp/common.h) because it made these files larger on MIPS. Signed-off-by: James Byrne <james.byrne@origamienergy.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-03-30libbb: mark scripted_main() as externally visibleRon Yorston
Building with individual binaries enabled fails when embedded script applets are included: /tmp/ccIvMFZg.o: In function `main': applet.c:(.text.main+0x20): undefined reference to `scripted_main' Mark scripted_main() as externally visible. Reported-by: Yann E. MORIN <yann.morin.1998@free.fr> Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-01-01single-applet build --help had extra \n, removeDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-27hush: allow hush to run embedded scriptsRon Yorston
Embedded scripts require a shell to be present in the BusyBox binary. Allow either ash or hush to be used for this purpose. If both are enabled ash takes precedence. The size of the binary is unchanged in the default configuration: both ash and hush are present but support for embedded scripts isn't compiled into hush. Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-18busybox: add '--show SCRIPT' option to display scriptsRon Yorston
Add an option to allow the content of embedded scripts to be displayed. This includes applet scripts, custom scripts and the .profile script. function old new delta busybox_main 624 701 +77 find_script_by_name - 24 +24 scripted_main 41 35 -6 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/1 up/down: 101/-6) Total: 95 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-17Treat custom and applet scripts as appletsRon Yorston
BusyBox has support for embedded shell scripts. Two types can be distinguished: custom scripts and scripts implementing applets. Custom scripts should be placed in the 'embed' directory at build time. They are given a default applet configuration and appear as applets to the user but no further configuration is possible. Applet scripts are integrated with the BusyBox build system and are intended to be used to ship standard applets that just happen to be implemented as scripts. They can be configured at build time and appear just like native applets. Such scripts should be placed in the 'applets_sh' directory. A stub C program should be written to provide the usual applet configuration details and placed in a suitable subsystem directory. It may be helpful to have a configuration option to enable any dependencies the script requires: see the 'nologin' applet for an example. function old new delta scripted_main - 41 +41 applet_names 2773 2781 +8 applet_main 1600 1604 +4 i2cdetect_main 672 674 +2 applet_suid 100 101 +1 applet_install_loc 200 201 +1 applet_flags 100 101 +1 packed_usage 33180 33179 -1 tryexec 159 152 -7 evalcommand 1661 1653 -8 script_names 9 - -9 packed_scripts 123 114 -9 complete_cmd_dir_file 826 811 -15 shellexec 271 254 -17 find_command 1007 990 -17 busybox_main 642 624 -18 run_applet_and_exit 100 78 -22 find_script_by_name 51 - -51 ------------------------------------------------------------------------------ (add/remove: 1/2 grow/shrink: 6/9 up/down: 58/-174) Total: -116 bytes text data bss dec hex filename 950034 477 7296 957807 e9d6f busybox_old 949918 477 7296 957691 e9cfb busybox_unstripped Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-02libarchive: add a function to unpack embedded dataRon Yorston
Similar code to unpack embedded data is used to decompress usage messages, embedded scripts and the config file (in the non-default bbconfig applet). Moving this code to a common function reduces the size of the default build and hides more of the internals of libarchive. function old new delta unpack_bz2_data - 135 +135 bb_show_usage 137 157 +20 get_script_content 32 47 +15 unpack_scripts 119 - -119 unpack_usage_messages 124 - -124 ------------------------------------------------------------------------------ (add/remove: 1/2 grow/shrink: 2/0 up/down: 170/-243) Total: -73 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-01busybox: show embedded scripts in applet listDenys Vlasenko
function old new delta busybox_main 624 642 +18 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-01ash: recognize embedded scripts in SH_STANDALONE modeRon Yorston
function old new delta find_script_by_name - 51 +51 shellexec 254 271 +17 find_command 990 1007 +17 evalcommand 1653 1661 +8 doCommands 2233 2222 -11 run_applet_and_exit 128 100 -28 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 6/4 up/down: 104/-52) Total: 52 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-01claenups for previous commitDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-11-01ash: allow shell scripts to be embedded in the binaryDenys Vlasenko
To assist in the deployment of shell scripts it may be convenient to embed them in the BusyBox binary. 'Embed scripts in the binary' takes any files in the directory 'embed', concatenates them with null separators, compresses them and embeds them in the binary. When scripts are embedded in the binary, scripts can be run as 'busybox SCRIPT [ARGS]' or by usual (sym)link mechanism. embed/nologin is provided as an example. function old new delta packed_scripts - 123 +123 unpack_scripts - 87 +87 ash_main 1103 1171 +68 run_applet_and_exit 78 128 +50 get_script_content - 32 +32 script_names - 10 +10 expmeta 663 659 -4 ------------------------------------------------------------------------------ (add/remove: 4/0 grow/shrink: 2/1 up/down: 370/-4) Total: 366 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-07-17whitespace fixesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-07-09usage: do not print trailing space for commands which have no argumentsDenys Vlasenko
function old new delta bb_show_usage 120 130 +10 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-04-08bzip2: fix two crashes on corrupted archivesDenys Vlasenko
As it turns out, longjmp'ing into freed stack is not healthy... function old new delta unpack_usage_messages - 97 +97 unpack_bz2_stream 369 409 +40 get_next_block 1667 1677 +10 get_bits 156 155 -1 start_bunzip 212 183 -29 bb_show_usage 181 120 -61 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 2/3 up/down: 147/-91) Total: 56 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-10-05whitespace and comment format fixes, no code changesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-08libbb: simplify NOFORK/NOEXEC defines, move set_task_comm to libbbDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-07noexec: consolidate codeDenys Vlasenko
function old new delta run_noexec_applet_and_exit - 61 +61 find_applet_by_name 128 124 -4 run_applet_no_and_exit 441 434 -7 tryexec 169 152 -17 pseudo_exec_argv 338 321 -17 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 0/6 up/down: 61/-48) Total: 13 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-07noexec: set comm field for noexecsDenys Vlasenko
function old new delta set_task_comm - 18 +18 tryexec 152 159 +7 pseudo_exec_argv 321 328 +7 main 106 97 -9 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 3/2 up/down: 34/-13) Total: 23 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-29standalone shell / prefer_applets: fix "exe" in comm fieldsDenys Vlasenko
function old new delta main 92 106 +14 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-29shell: make standalone shell tab-complete "busybox"Denys Vlasenko
function old new delta busybox_main - 624 +624 packed_usage 31758 31777 +19 applet_names 2638 2646 +8 applet_main 1528 1532 +4 applet_install_loc 191 192 +1 run_applet_and_exit 681 78 -603 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 4/1 up/down: 656/-603) Total: 53 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-10libbb: do not die if setgid/setuid(real_id) on startup failsDenys Vlasenko
Based on a patch from Steven McDonald <steven@steven-mcdonald.id.au>: This makes 'unshare --user' work correctly in the case where the user's shell is provided by busybox itself. 'unshare --user' creates a new user namespace without any uid mappings. As a result, /bin/busybox is setuid nobody:nogroup within the namespace, as that is the only user. However, since no uids are mapped, attempting to call setgid/setuid fails, even though this would do nothing: $ unshare --user ./busybox.broken ash ash: setgid: Invalid argument 'unshare --map-root-user' still works, but because Linux only allows uid/gid mappings to be set up once, creating a root mapping makes such a namespace useless for creating multi-user containers. With this patch, setgid and setuid will not be called in the case where they would do nothing, which is always the case inside a new user namespace because all uids are effectively mapped to nobody: $ id -u 1000 $ ls -lh busybox.fixed -rwsr-xr-x 1 root root 826.2K May 21 00:33 busybox.fixed $ unshare --user ./busybox.fixed ash $ id -u 65534 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-07main: fix the case where user has "halt" as login shell. Closes 9986Denys Vlasenko
halt::0:0::/:/sbin/halt function old new delta run_applet_and_exit 748 751 +3 run_applet_no_and_exit 467 459 -8 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-07-03fixes for bugs found by make_single_applets.shDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-01-11busybox: stop depending on FEATURE_AUTOWIDTH for applet listDenys Vlasenko
Many other appletw don't - they unconditionally use get_terminal_wodth(), and here the amount of code saved by FEATURE_AUTOWIDTH=n is tiny. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-01-06Automatically disable FEATURE_COMPRESS_USAGE for small builds.Denys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-01-03appletlib: avoid warning on unused function ingroupCristian Ionescu-Idbohrn
libbb/appletlib.c:558:12: warning: 'ingroup' defined but not used [-Wunused-function] static int ingroup(uid_t u, gid_t g) ^~~~~~~ That function is used only if FEATURE_SUID_CONFIG is also enabled. Signed-off-by: Cristian Ionescu-Idbohrn <cristian.ionescu-idbohrn@axis.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-12-23fix breakage found by mass one-applet buildsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-11-28Do not print useless empty line after list of appletsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-11-18Fix allnoconfig warningsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-10-03hush: add commented-out debug printouts in "memleak" built-inDenys Vlasenko
Allocation addresses of malloc() are jittery, thought I had a mem leak in hush, but it was malloc variability. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-08-19hush: fix a bug in FEATURE_SH_STANDALONE=y config. Closes 9186Denys Vlasenko
Run this in a "sh SCRIPT": sha256sum /dev/null echo END sha256sum is a NOEXEC applet. It runs in a forked child. Then child exit()s. By this time, entire script is read, and buffered in a FILE object from fopen("SCRIPT"). But fgetc() did not consume entire input. exit() lseeks back by -9 bytes, from <eof> to 'e' in 'echo'. (this may be libc-specific). This change of fd position *is shared with the parent*! Now parent can read more, and it thinks there is another "echo END". End result: two "echo END"s are run. Fix this by _exit()ing instead. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-07-05build system: fix a few warnings for allnoconfig buildDenys Vlasenko
Not that allnoconfig build is useful in any way... Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-07-05libbb: suppress warning about run_applet_and_exitRon Yorston
When busybox is configured to contain a single applet an unnecessary declaration of run_applet_and_exit results in a warning. Move the declaration to avoid this. Reported-by: Lauri Kasanen <curaga@operamail.com> Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-06-19libbb: move common code into run_applet_and_exitRon Yorston
Both calls to run_applet_and_exit are followed by the same code to print an error message and return status 127. Remove this duplication and make run_applet_and_exit static. function old new delta run_applet_and_exit 675 667 -8 main 119 92 -27 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-35) Total: -35 bytes Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-06-18Allow "busybox <applet>" to work when busybox is disabledRon Yorston
A recent commit made it possible to disable BusyBox's --install and --list options. However it also stopped "busybox <applet> <params>" from working. Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-05-31Make busybox an optional appletDenys Vlasenko
If it's disabled, code shrinks by about 900 bytes: function old new delta usr_bin 10 - -10 usr_sbin 11 - -11 install_dir 20 - -20 applet_install_loc 184 - -184 run_applet_and_exit 686 21 -665 ------------------------------------------------------------------------------ (add/remove: 0/4 grow/shrink: 0/1 up/down: 0/-890) Total: -890 bytes text data bss dec hex filename 911327 493 7336 919156 e0674 busybox_old 909848 493 7336 917677 e00ad busybox_unstripped but busybox executable by itself does not say anything useful: $ busybox busybox: applet not found Based on the patch by Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-15Rewrite iteration through applet names to save a few bytesRon Yorston
function old new delta run_applet_and_exit 758 755 -3 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-3) Total: -3 bytes In standalone shell mode the saving increases to 17 bytes. Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-03find_applet_by_name: loop index should be signedRon Yorston
The loop for (j = ARRAY_SIZE(applet_nameofs)-1; j >= 0; j--) { was intended to terminate when j goes negative, so j needs to be signed. Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-03main(): add a TODO about finding a use for _end[] areaDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-02typo fixDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-02find_applet_by_name: add an example of faster linear search codeDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-03-30applet_tables: save space by removing applet name offsetsRon Yorston
The array applet_nameofs consumes two bytes per applet. It encodes nofork/noexec flags suid flags the offset of the applet name in the applet_name string Change the applet_table build tool to store the flags in two separate arrays (applet_flags and applet_suid). Replace applet_nameofs[] with a smaller version that only stores a limited number of offsets. This requires changes to the macros APPLET_IS_NOFORK, APPLET_IS_NOEXEC and APPLET_SUID. According to Valgrind the original find_applet_by_name required 353 cycles per call, averaged over all names. Adjusting the number of known offsets allows space to be traded off against execution time: KNOWN_OFFSETS cycles bytes (wrt KNOWN_OFFSETS = 0) 0 9057 - 2 4604 32 4 2407 75 8 1342 98 16 908 130 32 884 194 This patch uses KNOWN_OFFSETS = 8. v2: Remove some dead code from the applet_table tool; Treat the applet in the middle of the table as a special case. v3: Use the middle applet to adjust the start of the linear search as well as the last applet found. v4: Use an augmented linear search in find_applet_by_name. Drop the special treatment of the middle name from get_applet_name: most of the advantage now derives from the last stored value. v5: Don't store index in applet_nameofs, it can be calculated. v6: Tweaks by Denys function old new delta find_applet_by_name 25 125 +100 applet_suid - 92 +92 run_applet_no_and_exit 452 460 +8 run_applet_and_exit 695 697 +2 applet_name_compare 31 - -31 applet_nameofs 734 14 -720 ------------------------------------------------------------------------------ (add/remove: 1/1 grow/shrink: 3/1 up/down: 202/-751) Total: -549 bytes text data bss dec hex filename 925464 906 17160 943530 e65aa busybox_old 924915 906 17160 942981 e6385 busybox_unstripped Signed-off-by: Ron Yorston <rmy@pobox.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-30busybox: alter help message in standalone shell modeRon Yorston
Signed-off-by: Ron Yorston <rmy@frippery.org> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-10-23libbb: factor out code which queries screen widthDenys Vlasenko
function old new delta get_terminal_width - 17 +17 stty_main 1196 1197 +1 pstree_main 321 319 -2 ls_main 735 731 -4 watch_main 232 225 -7 bb_progress_update 714 706 -8 ps_main 555 543 -12 run_applet_and_exit 708 695 -13 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 1/6 up/down: 18/-46) Total: -28 byte Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-23 20:00:05 +0000