exec: support unlimited resources

TODO

@@ -25,6 +25,8 @@ F15:
 
 Features:
 
+* allow port = 0 in .socket units
+
 * rename systemd-logger to systemd-stdio-syslog-bridge
 
 * introduce /usr/lib/binfmt.d/, /usr/lib/tmpfiles.d/

man/systemd.exec.xml

@@ -558,7 +558,10 @@
                                 various resource limits for executed
                                 processes. See
                                 <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
-                                for details.</para></listitem>
+                                for details. Use the string
+                                <varname>infinity</varname> to
+                                configure no limit on a specific
+                                resource.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>

src/load-fragment.c

@@ -30,6 +30,8 @@
 #include <sys/mount.h>
 #include <linux/fs.h>
 #include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 
 #include "unit.h"
 #include "strv.h"
@@ -965,7 +967,9 @@ static int config_parse_limit(
         assert(rvalue);
         assert(data);
 
-        if (safe_atollu(rvalue, &u) < 0) {
+        if (streq(rvalue, "infinity"))
+                u = (unsigned long long) RLIM_INFINITY;
+        else if (safe_atollu(rvalue, &u) < 0) {
                 log_error("[%s:%u] Failed to parse resource value, ignoring: %s", filename, line, rvalue);
                 return 0;
         }