[Toybox] [PATCH] hostname: add -s/-f and -d.

[enh]

At least the AOSP build doesn't try to _set_ the hostname...
---
toys/lsb/hostname.c | 36 ++++++++++++++++++++++++------------
1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/toys/lsb/hostname.c b/toys/lsb/hostname.c
index 0a1f9b1..4b9347d 100644
--- a/toys/lsb/hostname.c
+++ b/toys/lsb/hostname.c
@@ -4,48 +4,60 @@
*
* http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/hostname.html

-USE_HOSTNAME(NEWTOY(hostname, "bF:", TOYFLAG_BIN))
+USE_HOSTNAME(NEWTOY(hostname, ">1bdsfF:[!bdsf]", TOYFLAG_BIN))

config HOSTNAME
bool "hostname"
default y
help
- usage: hostname [-b] [-F FILENAME] [newname]
+ usage: hostname [-bsf] [-F FILENAME] [newname]

- Get/Set the current hostname
+ Get/set the current hostname.

- -b Set hostname to 'localhost' if otherwise unset
- -F Set hostname to contents of FILENAME
+ -b set hostname to 'localhost' if otherwise unset
+ -d show DNS domain name (no host)
+ -f show fully-qualified name (host+domain, FQDN)
+ -F set hostname to contents of FILENAME
+ -s show short host name (no domain)
*/

#define FOR_hostname
#include "toys.h"

GLOBALS(
- char *fname;
+ char *F;
)

void hostname_main(void)
{
- char *hostname = *toys.optargs;
+ char *hostname = *toys.optargs, *dot;
+ struct hostent *h;

- if (TT.fname && (hostname = xreadfile(TT.fname, 0, 0))) {
+ if (TT.F && (hostname = xreadfile(TT.F, 0, 0))) {
if (!*chomp(hostname)) {
if (CFG_TOYBOX_FREE) free(hostname);
- if (!(toys.optflags&FLAG_b)) error_exit("empty '%s'", TT.fname);
+ if (!(toys.optflags&FLAG_b)) error_exit("empty '%s'", TT.F);
hostname = 0;
}
}

+ // Implement -b.
if (!hostname && (toys.optflags&FLAG_b))
if (gethostname(toybuf, sizeof(toybuf)-1) || !*toybuf)
hostname = "localhost";

+ // Setting?
if (hostname) {
if (sethostname(hostname, strlen(hostname)))
perror_exit("set '%s'", hostname);
- } else {
- if (gethostname(toybuf, sizeof(toybuf)-1)) perror_exit("gethostname");
- xputs(toybuf);
+ return;
}
+
+ // Get the hostname.
+ if (gethostname(toybuf, sizeof(toybuf)-1)) perror_exit("gethostname");
+ if (!(h = gethostbyname(toybuf))) perror_exit("gethostbyname");
+ snprintf(toybuf, sizeof(toybuf), "%s", h->h_name);
+ dot = strchr(toybuf, '.');
+ if (toys.optflags&FLAG_s) *dot = '\0';
+ xputs(toys.optflags&FLAG_d ? dot+1 : toybuf);
}