More systemd friendly?

procServ.cc

@@ -59,8 +59,6 @@ RestartMode restartMode = restart;  // Child restart mode (restart/norestart/one
 bool   firstRun;                 // Has process run for purposes of oneshot restart mode
 char   *procservName;            // The name of this beast (server)
 char   *childName;               // The name of that beast (child)
-char   *childExec;               // Exec to run as child
-char   **childArgv;              // Argv for child process
 int    connectionNo;             // Total number of connections
 char   *ignChars = NULL;         // Characters to ignore
 char   killChar = 0x18;          // Kill command character (default: ^X)
@@ -214,6 +212,7 @@ int main(int argc,char * argv[])
     const size_t BUFLEN = 512;
     char buff[BUFLEN];
     std::string infofile;
+    char *childExec = NULL;               // Exec to run as child
 
     time(&procServStart);             // remember start time
     procservName = argv[0];
@@ -455,12 +454,33 @@ int main(int argc,char * argv[])
     command = argv[optind];
 
     if (childName == NULL) childName = command;
-    childArgv = argv + optind - 1;
+    char** childArgv = argv + optind - 1;
     if (childExec == NULL) {
         childArgv++;
         childExec = command;
     }
 
+    // reallocate argv[] storage, and expand any unexpanded arguments
+    std::vector<std::string> argvStore;
+    for(char** av = childArgv; *av; av++) {
+        if((*av)[0]=='$') { // expand command from environment
+            const char *ev = getenv(&(*av)[1]);
+            if(!ev) {
+                fprintf(stderr, "argument references %s which is not set in environment\n", *av);
+                exit(1);
+            }
+            argvStore.push_back(ev);
+
+        } else {
+            argvStore.push_back(*av);
+        }
+    }
+    std::vector<char*> argvBuf(argvStore.size()+1); // include trailing NULL
+    for(size_t i=0, N=argvStore.size(); i<N; i++) {
+        argvBuf[i] = argvStore[i].data();
+    }
+    childArgv = argvBuf.data();
+
     if (!stampFormat) {
         char *tmp = (char*) calloc(strlen(timeFormat)+4, 1);
         if (tmp) {

procServ@.service

@@ -0,0 +1,36 @@
+[Unit]
+Description="Managed process %i"
+
+[Service]
+Type=simple
+
+ExecStart=/usr/bin/procServ \
+  --foreground --logfile - --name %N \
+  --info-file %t/%N/info \
+  --port 0 \
+  --port unix:%t/%N/control \
+  $PROCCMD
+
+StandardOutput=syslog
+StandardError=inherit
+SyslogIdentifier=%N
+
+# Create %t/%N
+RuntimeDirectory=%N
+
+# What, where, who
+#Environment="PROCCMD=./st.cmd"
+#WorkingDirectory=/
+#User=softioc
+#Group=softioc
+
+# Permit RT priority for non-root
+#AmbientCapabilities=cap_ipc_lock
+#LimitRTPRIO=50
+#LimitMEMLOCK=256M
+
+[Install]
+# --system
+WantedBy=multi-user.target
+# --user
+#WantedBy=default.target