[PATCH s6] s6-softlimit: add -P option for RLIMIT_RTPRIO

[Alyssa Ross]

Bash ulimit uses -r for this, but in s6-softlimit that was already
taken.  I could have used -R, but Bash uses that for RLIMIT_RTTIME, so
I didn't want to claim that one and create a similarly difficult
decision for somebody adding that in future.  I decided to use -P (for
"priority") as the least bad still-available option.
---
 doc/s6-softlimit.html                 | 3 ++-
 src/daemontools-extras/s6-softlimit.c | 7 ++++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/doc/s6-softlimit.html b/doc/s6-softlimit.html
index 05701ce..49a5b40 100644
--- a/doc/s6-softlimit.html
+++ b/doc/s6-softlimit.html
@@ -25,7 +25,7 @@ s6-softlimit changes its process limits, then executes into 
another program.
 <h2> Interface </h2>
 
 <pre>
-     s6-softlimit [ -H | -h ] [ -a <em>allmem</em> ] [ -c <em>core</em> ] [ -d 
<em>data</em> ] [ -f <em>fsize</em> ] [ -l <em>lock</em> ] [ -m <em>mem</em> ] 
[ -o <em>ofiles</em> ] [ -p <em>proc</em> ] [ -r <em>res</em> ] [ -s 
<em>stack</em> ] [ -t <em>cpusecs</em> ] <em>prog...</em>
+     s6-softlimit [ -H | -h ] [ -a <em>allmem</em> ] [ -c <em>core</em> ] [ -d 
<em>data</em> ] [ -f <em>fsize</em> ] [ -l <em>lock</em> ] [ -m <em>mem</em> ] 
[ -o <em>ofiles</em> ] [ -P <em>prio</em> ] [ -p <em>proc</em> ] [ -r 
<em>res</em> ] [ -s <em>stack</em> ] [ -t <em>cpusecs</em> ] <em>prog...</em>
 </pre>
 
 <ul>
@@ -58,6 +58,7 @@ and s6-softlimit will die. There is virtually no reason to 
ever use this. </li>
  <li> <tt>-l&nbsp;<em>lock</em></tt>&nbsp;: limit the available locked memory 
to <em>lock</em> bytes. </li>
  <li> <tt>-m&nbsp;<em>mem</em></tt>&nbsp;: limit all types of memory to 
<em>mem</em> bytes. </li>
  <li> <tt>-o&nbsp;<em>ofiles</em></tt>&nbsp;: limit the number of open fds to 
<em>ofiles</em>. </li>
+ <li> <tt>-P&nbsp;<em>prio</em></tt>&nbsp;: limit the real-time priority to 
<em>prio</em>. </li>
  <li> <tt>-p&nbsp;<em>proc</em></tt>&nbsp;: limit the number of processes to 
<em>proc</em> (per user). </li>
  <li> <tt>-r&nbsp;<em>res</em></tt>&nbsp;: limit the available physical memory 
to <em>res</em> bytes. </li>
  <li> <tt>-s&nbsp;<em>stack</em></tt>&nbsp;: limit the available stack memory 
to <em>stack</em> bytes. </li>
diff --git a/src/daemontools-extras/s6-softlimit.c 
b/src/daemontools-extras/s6-softlimit.c
index d6112b2..beb7325 100644
--- a/src/daemontools-extras/s6-softlimit.c
+++ b/src/daemontools-extras/s6-softlimit.c
@@ -41,7 +41,7 @@ int main (int argc, char const *const *argv)
   PROG = "s6-softlimit" ;
   for (;;)
   {
-    int opt = subgetopt_r(argc, argv, "hHa:c:d:f:l:m:o:p:r:s:t:", &l) ;
+    int opt = subgetopt_r(argc, argv, "hHa:c:d:f:l:m:o:P:p:r:s:t:", &l) ;
     if (opt == -1) break ;
     switch (opt)
     {
@@ -103,6 +103,11 @@ int main (int argc, char const *const *argv)
       case 'p' :
 #ifdef RLIMIT_NPROC
         doit(RLIMIT_NPROC, l.arg) ;
+#endif
+        break ;
+      case 'P' :
+#ifdef RLIMIT_RTPRIO
+        doit(RLIMIT_RTPRIO, l.arg) ;
 #endif
         break ;
       case 'r' :

base-commit: a456cc8c4123e05f8d6c3620979961add7f0ed4e
-- 
2.51.0