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Stat cleanup.
From the mailing list:
Ok, first thing: clean up the help text. I realize what's there is copied verbatim from the man page, but that man page sucks. ("modification time" vs "change time"?) Took a bit of finagling to fit it in 80x24, but just made it.
GLOBALS() indent was still tab, change to two spaces. And I tend to put a blank line between options lib/args.c automatically fills out and normal globals.
We never do anything with date_stat_format() but immediately print it, might as well make the function do it.
The types[] array in do_stat() is a rough edge. Hmmm... there's no else case that sets the type in case it was unknown (such as 0). In theory, this never happens. In practice it means I can cheat slightly, given this observation:
$ find linux -name stat.h | xargs grep 'S_IF[A-Z]*[ \t]'
linux/include/uapi/linux/stat.h:#define S_IFMT 00170000
linux/include/uapi/linux/stat.h:#define S_IFSOCK 0140000
linux/include/uapi/linux/stat.h:#define S_IFLNK 0120000
linux/include/uapi/linux/stat.h:#define S_IFREG 0100000
linux/include/uapi/linux/stat.h:#define S_IFBLK 0060000
linux/include/uapi/linux/stat.h:#define S_IFDIR 0040000
linux/include/uapi/linux/stat.h:#define S_IFCHR 0020000
linux/include/uapi/linux/stat.h:#define S_IFIFO 0010000
I.E. the only place the I_IFBLAH constants occur a stat.h header in current linux code is in the generic stuff, it doesn't vary per target. (The access permission bits are actually subtly standardized in posix due to the command line arguments to chmod, although I'm sure cygwin finds a way to break. But the type fields, not so much. But linux has to be binary compatible with itself foreverish, and that's all I really care about.)
So, we have ALMOST have this going by twos, except there's no 8 and there is a 1. so let's make the 1 the default, feed a blank string into the 8... No, duh: octal. So it's actually 2, 4, 6, 8, 10, 12. So make the loop look like:
filetype = statf->st_mode & S_IFMT;
TT.ftname = types;
for (i = 1; filetype != (i*8192) && i < 7; i++)
TT.ftname += strlen(TT.ftname)+1;
Yes that's linux-specific, and I think I'm ok with that.
Printing all zeroes and pretending that's nanosecond resolution... either support it or don't. Let's see, supporting it is stat->st_atim.tv_nsec and similar... no mention of nanoseconds in strftime() (et tu, posix2008?) so pass it as a second argument and append it by hand... (Need to test that against musl...)
When we hit an unknown type in print_it() we print the literal character, which is right for %% but what about an unknown option?
$ stat -c %q /
?
Eh, I guess that's a "don't care". It didn't die with an error, that's the important thing.
I have a horrible idea for compressing the switch/case blocks, but should probably check this in and get some sleep for right now...
author | Rob Landley <rob@landley.net> |
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date | Tue, 28 May 2013 00:28:45 -0500 |
parents | 5dcfb58916a7 |
children | 9ccb7c975a5e |
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Toybox: all-in-one Linux command line. --- Getting started You can download static binaries for various targets from: http://landley.net/toybox/bin The special name "." indicates the current directory (just like ".." means the parent directory), and you can run a program that isn't in the $PATH by specifying a path to it, so this should work: wget http://landley.net/bin/toybox-x86_64 chmod +x toybox-x86_64 ./toybox-x86_64 echo hello world --- Building toybox Type "make help" for build instructions. Usually you want something like: make defconfig CFLAGS="--static" CROSS_COMPILE=armv5l- make toybox PREFIX=/path/to/root/filesystem make install The CROSS_COMPILE argument is optional, and without it builds a version of toybox to run on the current machine. Cross compiling requires an appropriately prefixed cross compiler toolchain, several example toolchains are available at: http;//landley.net/aboriginal/bin For the "CROSS_COMPILE=armv5l-" example above, download cross-compiler-armv5l.tar.bz2, extract it, and add its "bin" subdirectory to your $PATH. (And yes, the trailing - is significant, because the prefix includes a dash.) For more about cross compiling, see: http://landley.net/writing/docs/cross-compiling.html http://landley.net/aboriginal/architectures.html --- Using toybox The toybox build produces a multicall binary, a "swiss-army-knife" program that acts differently depending on the name it was called by (cp, mv, cat...). Installing toybox adds symlinks for each command name to the $PATH. The special "toybox" command treats its first argument as the command to run. With no arguments, it lists available commands. This allows you to use toybox without installing it. This is the only command that can have an arbitrary suffix (hence "toybox-armv5l"). The "help" command provides information about each command (ala "help cat"). --- Configuring toybox It works like the Linux kernel: allnoconfig, defconfig, and menuconfig edit a ".config" file that selects which features to include in the resulting binary. The maximum sane configuration is "make defconfig": allyesconfig isn't recommended for toybox because it enables unfinished commands and debug code. --- Creating a Toybox-based Linux system Toybox is not a complete operating system, it's a program that runs under an operating system. Booting a simple system to a shell prompt requires three packages: an operating system kernel (Linux) to drive the hardware, a program for the system to run (toybox), and a C library to tie them together (toybox has been tested with musl, uClibc, and glibc, on Android systems musl is recommended).</p> <p>The C library is part of a "toolchain", which is an integrated suite of compiler, assembler, and linker, plus the standard headers and libraries necessary to build C programs.</p> Static linking (with the --static option) copies the shared library contents into the program, resulting in larger but more portable programs. Dynamically linked programs (the default) Otherwise, the "dynamically" linked programs require the library to be present on the target system ("man ldd" and "man ld.so" for details) statically linked programs do not.</p> Toybox is not a kernel, it needs Linux to drive the hardware. An example toybox-based system is Aboriginal Linux: http://landley.net/aboriginal