ulimit: add new limits from Linux

Short options are taken from prlimit(1) where appropriate.

Closes #8786.

CHANGELOG.rst

@@ -34,6 +34,7 @@ Interactive improvements
 - The default command-not-found handler now reports a special error if there is a non-executable file (:issue:`8804`)
 - ``less`` and other interactive commands would occasionally be stopped when run in a pipeline with fish functions; this has been fixed (:issue:`8699`).
 - Case-changing autosuggestions generated mid-token now correctly append only the suffix, instead of duplicating the token (:issue:`8820`).
+- ``ulimit`` learned a number of new options for the resource limits available on Linux (:issue:`8786`).
 
 New or improved bindings
 ^^^^^^^^^^^^^^^^^^^^^^^^

doc_src/cmds/ulimit.rst

@@ -24,9 +24,15 @@ Use one of the following switches to specify which resource limit to set or repo
 **-d** or **--data-size**
     The maximum size of a process' data segment.
 
+**-e** or **--nice**
+    Controls the maximum nice value; on Linux, this value is subtracted from 20 to give the effective value.
+
 **-f** or **--file-size**
     The maximum size of files created by a process.
 
+**-i** or **--pending-signals**
+    The maximum number of signals that may be queued.
+
 **-l** or **--lock-size**
     The maximum size that may be locked into memory.
 
@@ -36,6 +42,12 @@ Use one of the following switches to specify which resource limit to set or repo
 **-n** or **--file-descriptor-count**
     The maximum number of open file descriptors.
 
+**-q** or **--queue-size**
+    The maximum size of data in POSIX message queues.
+
+**-r** or **--realtime-priority**
+    The maximum realtime scheduling priority.
+
 **-s** or **--stack-size**
     The maximum stack size.
 
@@ -48,6 +60,9 @@ Use one of the following switches to specify which resource limit to set or repo
 **-v** or **--virtual-memory-size**
     The maximum amount of virtual memory available to the shell.
 
+**-y** or **--realtime-maxtime**
+    The maximum contiguous realtime CPU time in microseconds.
+
 Note that not all these limits are available in all operating systems.
 
 The value of limit can be a number in the unit specified for the resource or one of the special values ``hard``, ``soft``, or ``unlimited``, which stand for the current hard limit, the current soft limit, and no limit, respectively.

share/completions/ulimit.fish

@@ -5,14 +5,19 @@ complete -c ulimit -s H -l hard -d "Set or get hard limit"
 complete -c ulimit -s a -l all -d "Get all current limits"
 complete -c ulimit -s c -l core-size -d "Maximum size of core files created"
 complete -c ulimit -s d -l data-size -d "Maximum size of a process's data segment"
+complete -c ulimit -s e -l nice -d "Control of maximum nice priority"
 complete -c ulimit -s f -l file-size -d "Maximum size of files created by the shell"
+complete -c ulimit -s i -l pending-signals -d "Maximum number of pending signals"
 complete -c ulimit -s l -l lock-size -d "Maximum size that may be locked into memory"
 complete -c ulimit -s m -l resident-set-size -d "Maximum resident set size"
 complete -c ulimit -s n -l file-descriptor-count -d "Maximum number of open file descriptors"
+complete -c ulimit -s q -l queue-size -d "Maximum bytes in POSIX message queues"
+complete -c ulimit -s r -l realtime-priority -d "Maximum realtime scheduling priority"
 complete -c ulimit -s s -l stack-size -d "Maximum stack size"
 complete -c ulimit -s t -l cpu-time -d "Maximum amount of cpu time in seconds"
 complete -c ulimit -s u -l process-count -d "Maximum number of processes available to a single user"
 complete -c ulimit -s v -l virtual-memory-size -d "Maximum amount of virtual memory available to the shell"
+complete -c ulimit -s y -l realtime-maxtime -d "Maximum contiguous realtime CPU time"
 
 complete -c ulimit -s h -l help -d "Display help and exit"
 

src/builtins/ulimit.cpp

@@ -2,7 +2,7 @@
 #include "config.h"  // IWYU pragma: keep
 
 #include "ulimit.h"
-    
+
 #include <sys/resource.h>
 
 #include <cerrno>
@@ -28,7 +28,13 @@ struct resource_t {
 static const struct resource_t resource_arr[] = {
     {RLIMIT_CORE, L"Maximum size of core files created", L'c', 1024},
     {RLIMIT_DATA, L"Maximum size of a process’s data segment", L'd', 1024},
+#ifdef RLIMIT_NICE
+    {RLIMIT_NICE, L"Control of maximum nice priority", L'e', 1},
+#endif
     {RLIMIT_FSIZE, L"Maximum size of files created by the shell", L'f', 1024},
+#ifdef RLIMIT_SIGPENDING
+    {RLIMIT_SIGPENDING, L"Maximum number of pending signals", L'i', 1},
+#endif
 #ifdef RLIMIT_MEMLOCK
     {RLIMIT_MEMLOCK, L"Maximum size that may be locked into memory", L'l', 1024},
 #endif
@@ -36,6 +42,12 @@ static const struct resource_t resource_arr[] = {
     {RLIMIT_RSS, L"Maximum resident set size", L'm', 1024},
 #endif
     {RLIMIT_NOFILE, L"Maximum number of open file descriptors", L'n', 1},
+#ifdef RLIMIT_MSGQUEUE
+    {RLIMIT_MSGQUEUE, L"Maximum bytes in POSIX message queues", L'q', 1024},
+#endif
+#ifdef RLIMIT_RTPRIO
+    {RLIMIT_RTPRIO, L"Maximum realtime scheduling priority", L'r', 1},
+#endif
     {RLIMIT_STACK, L"Maximum stack size", L's', 1024},
     {RLIMIT_CPU, L"Maximum amount of CPU time in seconds", L't', 1},
 #ifdef RLIMIT_NPROC
@@ -43,6 +55,9 @@ static const struct resource_t resource_arr[] = {
 #endif
 #ifdef RLIMIT_AS
     {RLIMIT_AS, L"Maximum amount of virtual memory available to each process", L'v', 1024},
+#endif
+#ifdef RLIMIT_RTTIME
+    {RLIMIT_RTTIME, L"Maximum contiguous realtime CPU time", L'y', 1},
 #endif
     {0, nullptr, 0, 0}};
 
@@ -158,21 +173,26 @@ maybe_t<int> builtin_ulimit(parser_t &parser, io_streams_t &streams, const wchar
     bool soft = false;
     int what = RLIMIT_FSIZE;
 
-    static const wchar_t *const short_options = L":HSacdflmnstuvh";
+    static const wchar_t *const short_options = L":HSacdefilmnqrstuvyh";
     static const struct woption long_options[] = {
         {L"all", no_argument, nullptr, 'a'},
         {L"hard", no_argument, nullptr, 'H'},
         {L"soft", no_argument, nullptr, 'S'},
         {L"core-size", no_argument, nullptr, 'c'},
         {L"data-size", no_argument, nullptr, 'd'},
+        {L"nice", no_argument, nullptr, 'e'},
         {L"file-size", no_argument, nullptr, 'f'},
+        {L"pending-signals", no_argument, nullptr, 'i'},
         {L"lock-size", no_argument, nullptr, 'l'},
         {L"resident-set-size", no_argument, nullptr, 'm'},
         {L"file-descriptor-count", no_argument, nullptr, 'n'},
+        {L"queue-size", no_argument, nullptr, 'q'},
+        {L"realtime-priority", no_argument, nullptr, 'r'},
         {L"stack-size", no_argument, nullptr, 's'},
         {L"cpu-time", no_argument, nullptr, 't'},
         {L"process-count", no_argument, nullptr, 'u'},
         {L"virtual-memory-size", no_argument, nullptr, 'v'},
+        {L"realtime-maxtime", no_argument, nullptr, 'y'},
         {L"help", no_argument, nullptr, 'h'},
         {nullptr, 0, nullptr, 0}};
 
@@ -200,10 +220,22 @@ maybe_t<int> builtin_ulimit(parser_t &parser, io_streams_t &streams, const wchar
                 what = RLIMIT_DATA;
                 break;
             }
+#ifdef RLIMIT_NICE
+            case 'e': {
+                what = RLIMIT_NICE;
+                break;
+            }
+#endif
             case 'f': {
                 what = RLIMIT_FSIZE;
                 break;
             }
+#ifdef RLIMIT_SIGPENDING
+            case 'i': {
+                what = RLIMIT_SIGPENDING;
+                break;
+            }
+#endif
 #ifdef RLIMIT_MEMLOCK
             case 'l': {
                 what = RLIMIT_MEMLOCK;
@@ -220,6 +252,18 @@ maybe_t<int> builtin_ulimit(parser_t &parser, io_streams_t &streams, const wchar
                 what = RLIMIT_NOFILE;
                 break;
             }
+#ifdef RLIMIT_MSGQUEUE
+            case 'q': {
+                what = RLIMIT_MSGQUEUE;
+                break;
+            }
+#endif
+#ifdef RLIMIT_RTPRIO
+            case 'r': {
+                what = RLIMIT_RTPRIO;
+                break;
+            }
+#endif
             case 's': {
                 what = RLIMIT_STACK;
                 break;
@@ -239,6 +283,12 @@ maybe_t<int> builtin_ulimit(parser_t &parser, io_streams_t &streams, const wchar
                 what = RLIMIT_AS;
                 break;
             }
+#endif
+#ifdef RLIMIT_RTTIME
+            case 'y': {
+                what = RLIMIT_RTTIME;
+                break;
+            }
 #endif
             case 'h': {
                 builtin_print_help(parser, streams, cmd);