The SOURCE_DATE_EPOCH is an effort of the Reproducible Builds
organization to make timestamps/build dates in compiled tools
deterministic over several repetitive builds.
Busybox shows by default the build date timestamp which changes whenever
compiled. To have a reasonable accurate build date while staying
reproducible, it's possible to use the *date of last source
modification* rather than the current time and date.
Further information on SOURCE_DATE_EPOCH are available online [1].
This patch modifies `confdata.c` so that the content of the
SOURCE_DATE_EPOCH env variable is used as timestamp.
To be independent of different timezones between builds, whenever
SOURCE_DATE_EPOCH is defined the GMT time is used.
[1]: https://reproducible-builds.org/docs/source-date-epoch/
Signed-off-by: Paul Spooren <mail@aparcar.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
When include/applets.h is re-generated
it generates code macros in include/applets.h e.g.
IF_XZCAT(APPLET_ODDNAME(xzcat, unxz, BB_DIR_USR_BIN, BB_SUID_DROP, xzcat))
...
IF_CHVT(APPLET_NOEXEC(chvt, chvt, BB_DIR_USR_BIN, BB_SUID_DROP, chvt))
...
sed is used to process source files like below to feed into this header
generation
sed -n 's@^//applet:@@p' "$srctree"/*/*.c "$srctree"/*/*/*.c
this means we let shell decide the order of .c files being fed into sed
tool, applets.h has code snippets thats generated out of code fragments
from these .c files and the order of the generated code depends on the
order of .c files being fed to sed and then piped to generate tool, even
though the generated code is logically same, it does result in re-odered
code in applets.h based on which shell was used during build on exact busybox
sources since sort order is different based on chosen locale and also default shell
being bash or dash
This sets the environment variable LC_ALL to the value C, which will
enforce bytewise sorting, irrespective of the shell
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
A CR in the gcc output would cause the following to show throughout build:
: invalid numberbox-1.32.1/scripts/gcc-version.sh: line 12: printf: 9
Signed-off-by: Chris Renshaw <osm0sis@outlook.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Commit 4bdc914ff (build system: fix compiler warnings) added a
test on the return value of fgets() in split-include.c.
During bisection it's possible to go back to a state where a
configuration value didn't exist. This results in an empty
include file corresponding to the missing feature. If a
subsequent bisection returns to a state where the feature exists
split-include treats the empty file as an error and the build
fails.
Add a call to ferror() to distinguish between fgets() failing
due to an error and due to there being no data to read.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Disable 'echo' in the default config, run 'make baseline', then
re-enable 'echo' and run 'make bloatcheck':
function old new delta
.rodata 182521 182622 +101
packed_usage 33714 33792 +78
applet_main 3168 3176 +8
applet_names 2730 2735 +5
applet_suid 99 100 +1
applet_install_loc 198 199 +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 6/0 up/down: 194/0) Total: 194 bytes
text data bss dec hex filename
955052 4195 1808 961055 eaa1f busybox_old
955153 4195 1808 961156 eaa84 busybox_unstripped
The Total bytes value doesn't equal the change in the size of the
binary. The packed_usage and applet_* items are in .rodata and
are counted twice. With this modified bloat-o-meter the size of
named items is deducted from .rodata:
function old new delta
packed_usage 33714 33792 +78
applet_main 3168 3176 +8
.rodata 105105 105113 +8
applet_names 2730 2735 +5
applet_suid 99 100 +1
applet_install_loc 198 199 +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 6/0 up/down: 101/0) Total: 101 bytes
text data bss dec hex filename
955052 4195 1808 961055 eaa1f busybox_old
955153 4195 1808 961156 eaa84 busybox_unstripped
v2: Sections numbered less than 10 were always being omitted from
consideration because splitting "[ 1] .interp" leaves "1]" in
x[1] where the section name is expected. This wasn't a problem
for .rodata (numbered 15 in my testing) but let's fix it anyway.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
When using GNU Make >=4.3, the KBUILD_STR() definition interferes badly
with dependency checks during build, and forces a complete rebuild every
time Make runs.
In if_changed_rule, Kconfig checks if the command used to build a file
has changed since last execution. The previous command is stored in the
generated .<file>.o.cmd file. For example applets/.applets.o.cmd defines
a "cmd_applets/applets.o" variable:
cmd_applets/applets.o := gcc ... -D"KBUILD_STR(s)=#s" ...
Here the '#' should be escaped with a backslash, otherwise GNU Make
interprets it as starting a comment, and ignore the rest of the
variable. As a result of this truncation, the previous command doesn't
equal the new command and Make rebuilds each target.
The problem started to appear when GNU Make 4.3 (released January 2020),
introduced a backward-incompatible fix to macros containing a '#'. While
the above use of '#', a simple Make variable, still needs to be escaped,
a '#' within a function invocation doesn't need to be escaped anymore.
As Martin Dorey explained on the GNU Make discussion [1], the above
declaration is generated from make-cmd, defined as:
make-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(cmd_$(1))))
Since GNU Make 4.3, the first argument of subst should not have a
backslash. make-cmd now looks for literally \# and doesn't find it, and
as a result doesn't add the backslash when generating .o.cmd files.
[1] http://savannah.gnu.org/bugs/?20513
We could fix it by changing make-cmd to "$(subst #,\#,...)", but to
avoid compatibility headaches, simply get rid of the KBUILD_STR
definition, as done in Linux by b42841b7bb62 ("kbuild: Get rid of
KBUILD_STR"). Quote the string arguments directly rather than asking the
preprocessor to quote them.
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
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>
- Force a rebuild if a script in applets_sh is changed.
- Move the dummy usage messages for custom applets to usage.h and
change the name from 'dummy' to 'scripted'.
- Hide an error from gen_build_files.sh if an embed directory exists
but is empty.
- Tidy up embedded_scripts script.
v2: Remove a couple of unnecessary tests in embedded_scripts, as
pointed out by Xabier Oneca.
Drop the stripping of comments.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Before:
Trying libraries: crypt m resolv
Library crypt is not needed, excluding it
Library m is needed, can't exclude it (yet)
Library resolv is needed, can't exclude it (yet)
Library m is needed, can't exclude it (yet)
Library resolv is needed, can't exclude it (yet)
Final link with: m resolv
After:
Trying libraries: crypt m resolv
Library crypt is not needed, excluding it
Library m is needed, can't exclude it (yet)
Library resolv is needed, can't exclude it (yet)
Final link with: m resolv
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The build process for embedded scripts didn't have consistent
support for saving output to a different directory.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
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>
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>
This is more usable for programmatically checking the validity of a
release.
Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
minips is a pure alias to ps, just in case someone needs 100% klibc-utils compat.
nuke is a primitive version of "rm -rf" without options and error checks. ~30 bytes.
resume is a tool for initramfs which resumes from a given block device.
function old new delta
resume_main - 582 +582
packed_usage 31640 31712 +72
nuke_main - 28 +28
xstrtoull - 24 +24
applet_names 2646 2665 +19
applet_main 1532 1544 +12
applet_suid 96 97 +1
applet_install_loc 192 193 +1
applet_flags 96 97 +1
------------------------------------------------------------------------------
(add/remove: 5/0 grow/shrink: 6/0 up/down: 740/0) Total: 740 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
CONFIG_FEATURE_USE_BSS_TAIL code was aliasing bb_common_bufsiz1 to _end.
This is unreliable: _end may be not sufficiently aligned.
Change code to simply enlarge COMMON_BUFSIZE when we detect that _end
has significant amount of space to the end of page.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
