Add a command line option to allow the user to provide an upper bound

for the number of connected processes. This is still lame but better
than asking her to recompile.
Part of fixing BZ #337869.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14838

diff --git a/auxprogs/valgrind-listener.c b/auxprogs/valgrind-listener.c
index 15b23abd949cfdf6147ade591f84426d2b3c50a9..8da7a288b480376d0e66d79e5d6898d078cafe76 100644 (file)
--- a/auxprogs/valgrind-listener.c
+++ b/auxprogs/valgrind-listener.c
@@ -57,9 +57,13 @@
 
 /*---------------------------------------------------------------*/
 
-/* The maximum allowable number concurrent connections. */
-#define M_CONNECTIONS 50
+/* The default allowable number of concurrent connections. */
+#define  M_CONNECTIONS_DEFAULT 50
+/* The maximum allowable number of concurrent connections. */
+#define  M_CONNECTIONS_MAX     5000
 
+/* The maximum allowable number of concurrent connections. */
+unsigned M_CONNECTIONS = 0;
 
 /*---------------------------------------------------------------*/
 
@@ -98,8 +102,8 @@ static void my_assert_fail ( const char* expr, const char* file, int line, const
 
 /* holds the fds for connections; zero if slot not in use. */
 int conn_count = 0;
-int           conn_fd[M_CONNECTIONS];
-struct pollfd conn_pollfd[M_CONNECTIONS];
+int           *conn_fd;
+struct pollfd *conn_pollfd;
 
 
 static void set_nonblocking ( int sd )
@@ -167,8 +171,8 @@ static void snooze ( void )
 }
 
 
-/* returns 0 if invalid, else port # */
-static int atoi_portno ( const char* str )
+/* returns 0 if negative, or > BOUND or invalid characters were found */
+static int atoi_with_bound ( const char* str, int bound )
 {
    int n = 0;
    while (1) {
@@ -178,9 +182,17 @@ static int atoi_portno ( const char* str )
          return 0;
       n = 10*n + (int)(*str - '0');
       str++;
-      if (n >= 65536) 
+      if (n >= bound)
          return 0;
    }
+   return n;
+}
+
+/* returns 0 if invalid, else port # */
+static int atoi_portno ( const char* str )
+{
+   int n = atoi_with_bound(str, 65536);
+
    if (n < 1024)
       return 0;
    return n;
@@ -193,18 +205,22 @@ static void usage ( void )
       "\n"
       "usage is:\n"
       "\n"
-      "   valgrind-listener [--exit-at-zero|-e] [port-number]\n"
+      "   valgrind-listener [--exit-at-zero|-e] [--max-connect=INT] [port-number]\n"
       "\n"
       "   where   --exit-at-zero or -e causes the listener to exit\n"
       "           when the number of connections falls back to zero\n"
       "           (the default is to keep listening forever)\n"
       "\n"
+      "           --max-connect=INT can be used to increase the maximum\n"
+      "           number of connected processes (default = %d).\n"
+      "           INT must be positive and less than %d.\n"
+      "\n"
       "           port-number is the default port on which to listen for\n"
       "           connections.  It must be between 1024 and 65535.\n"
       "           Current default is %d.\n"
       "\n"
       ,
-      VG_CLO_DEFAULT_LOGPORT
+      M_CONNECTIONS_DEFAULT, M_CONNECTIONS_MAX, VG_CLO_DEFAULT_LOGPORT
    );
    exit(1);
 }
@@ -247,6 +263,11 @@ int main (int argc, char** argv)
           || 0==strcmp(argv[i], "-e")) {
          exit_when_zero = 1;
       }
+      else if (0 == strncmp(argv[i], "--max-connect=", 14)) {
+         M_CONNECTIONS = atoi_with_bound(strchr(argv[i], '=') + 1, 5000);
+         if (M_CONNECTIONS <= 0 || M_CONNECTIONS > M_CONNECTIONS_MAX)
+            usage();
+      }
       else
       if (atoi_portno(argv[i]) > 0) {
          port = atoi_portno(argv[i]);
@@ -255,6 +276,16 @@ int main (int argc, char** argv)
       usage();
    }
 
+   if (M_CONNECTIONS == 0)   // nothing specified on command line
+      M_CONNECTIONS = M_CONNECTIONS_DEFAULT;
+
+   conn_fd     = malloc(M_CONNECTIONS * sizeof conn_fd[0]);
+   conn_pollfd = malloc(M_CONNECTIONS * sizeof conn_pollfd[0]);
+   if (conn_fd == NULL || conn_pollfd == NULL) {
+      fprintf(stderr, "Memory allocation failed; cannot continue.\n");
+      exit(1);
+   }
+
    banner("started");
    signal(SIGINT, sigint_handler);
 
@@ -326,9 +357,11 @@ int main (int argc, char** argv)
                  break;
 
            if (i >= M_CONNECTIONS) {
-              fprintf(stderr, "Too many concurrent connections.  "
-                              "Increase M_CONNECTIONS and recompile.\n");
-              panic("main -- too many concurrent connections");
+              fprintf(stderr, "\n\nMore than %d concurrent connections.\n"
+                      "Restart the listener giving --max-connect=INT on the\n"
+                      "commandline to increase the limit.\n\n",
+                      M_CONNECTIONS);
+              exit(1);
            }
 
            conn_fd[i] = new_sd;

diff --git a/docs/xml/manual-core.xml b/docs/xml/manual-core.xml
index f11e9b166b09e347c1dbf681b32f0eb57ff930c3..3ea5635e6ce748ba1ee8acfe675a02ab702c84c5 100644 (file)
--- a/docs/xml/manual-core.xml
+++ b/docs/xml/manual-core.xml
@@ -236,7 +236,7 @@ re-run, passing the <option>-v</option> option to Valgrind.  A second
     of each line of output it prints the current number of active
     connections in round brackets.</para>
 
-    <para><computeroutput>valgrind-listener</computeroutput> accepts two
+    <para><computeroutput>valgrind-listener</computeroutput> accepts three
     command-line options:</para>
     <!-- start of xi:include in the manpage -->
     <variablelist id="listener.opts.list">
@@ -248,6 +248,16 @@ re-run, passing the <option>-v</option> option to Valgrind.  A second
            send it Control-C.</para>
          </listitem>
        </varlistentry>
+       <varlistentry>
+         <term><option>--max-connext=INTEGER</option></term>
+         <listitem>
+           <para>By default, the listener can connect to up to 50 processes.
+             Occasionally, that number is too small. Use this option to
+             provide a different limit. E.g.
+             <computeroutput>--max-connext=100</computeroutput>.
+           </para>
+         </listitem>
+       </varlistentry>
        <varlistentry>
         <term><option>portnumber</option></term>
         <listitem>