With bash's read builtin it is possible to read from a file (e.g.
device-tree) until the first '\0' character:
IFS= read -r -d '' VARIABLE < file
In busybox ash the -d extension is also implemented, but checking the
read character for '\0' has to be performed after comparing with the
delimiter.
Signed-off-by: Christian Eggers <ceggers@arri.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Back in 2007, commit 0c97c9d437 ("'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>
NOEXEC'ed applets which use getopt() need this.
function old new delta
builtin_getopts 403 413 +10
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The POSIX standard only requires the read builtin to handle -r:
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/read.html
However, Bash introduced the option -d <DELIM> to override IFS for
just one invocation, and it is quite useful.
It is also super easy to implement in BusyBox' ash, so let's do that.
The motivation: This option is used by Git's test suite.
function old new delta
.rodata 163505 163587 +82
shell_builtin_read 1244 1289 +45
readcmd 233 259 +26
builtin_read 258 263 +5
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/0 up/down: 158/0) Total: 158 bytes
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Upstream commit 1:
Date: Fri, 23 Aug 2013 21:27:42 +1000
[VAR] Initialise OPTIND after importing environment
On Sat, Mar 23, 2013 at 01:46:20AM +0000, Chris F.A. Johnson wrote:
> According to both the dash man page and the POSIX spec, "When the
> shell is invoked, OPTIND is initialized to 1."
>
> However, it actually takes the value of the environment variable
> if it exists:
>
> $ OPTIND=4 dash -c 'echo "$OPTIND"'
> 4
> $ OPTIND=4 bash -c 'echo "$OPTIND"'
> 1
> $ OPTIND=4 ksh -c 'echo "$OPTIND"'
> 1
> $ OPTIND=4 ksh93 -c 'echo "$OPTIND"'
> 1
This patch fixes this by initialising OPTIND after importing the
environment.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Upstream commit 2:
Date: Tue, 7 Oct 2014 22:24:42 +0800
[VAR] Use setvareq to set OPTIND initially
There is no need to setvarint to set the initial value of OPTIND
of one. This patch switchs to setvareq which also lets us avoid
an unnecessary memory allocation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
The result of looking at "grep -F -B2 '*fill*' busybox_unstripped.map"
text data bss dec hex filename
829901 4086 1904 835891 cc133 busybox_before
829665 4086 1904 835655 cc047 busybox
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
We use functions from sys/resource.h in misc applets, but don't include
the header. This breaks building with newer glibc versions, so add the
include where needed.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
First change fixes "read -n NUM". Apparently poll() won't report
data availability if cc[VMIN] > 1 until there are at least cc[VMIN] bytes.
function old new delta
read_line_input 3885 3877 -8
shell_builtin_read 1097 1087 -10
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-18) Total: -18 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This change retains "or later" state! No licensing _changes_ here,
only form is adjusted (article, space between "GPL" and "v2" and so on).
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
function old new delta
shell_builtin_ulimit 494 498 +4
Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
