Add random port/report port in background, switch to malloc for data …

…buffers (ornladios#4183)

Add port randomization in background, switch to malloc for data buffers

source/adios2/toolkit/remote/remote_server.cpp

@@ -15,6 +15,7 @@
 #include <cstring> // strerror
 #include <errno.h> // errno
 #include <fcntl.h> // open
+#include <inttypes.h>
 #include <regex>
 #include <sys/stat.h>  // open, fstat
 #include <sys/types.h> // open
@@ -53,6 +54,9 @@ size_t TotalSimpleReads = 0;
 size_t TotalGets = 0;
 size_t SimpleFilesOpened = 0;
 size_t ADIOSFilesOpened = 0;
+static int report_port_selection = 0;
+int parent_pid;
+uint64_t random_cookie = 0;
 
 std::string readable_size(uint64_t size)
 {
@@ -276,17 +280,17 @@ static void GetRequestHandler(CManager cm, CMConnection conn, void *vevent, void
     {                                                                                              \
         _ReadResponseMsg Response;                                                                 \
         memset(&Response, 0, sizeof(Response));                                                    \
-        std::vector<T> RetData;                                                                    \
         auto var = f->m_io->InquireVariable<T>(VarName);                                           \
         if (f->m_mode == RemoteOpenRandomAccess)                                                   \
             var->SetStepSelection({GetMsg->Step, 1});                                              \
         if (GetMsg->BlockID != -1)                                                                 \
             var->SetBlockSelection(GetMsg->BlockID);                                               \
         if (GetMsg->Start)                                                                         \
             var->SetSelection(b);                                                                  \
+        Response.Size = var->SelectionSize() * sizeof(T);                                          \
+        T *RetData = (T *)malloc(Response.Size);                                                   \
         f->m_engine->Get(*var, RetData, Mode::Sync);                                               \
-        Response.Size = RetData.size() * sizeof(T);                                                \
-        Response.ReadData = (char *)RetData.data();                                                \
+        Response.ReadData = (char *)RetData;                                                       \
         Response.ReadResponseCondition = GetMsg->GetResponseCondition;                             \
         Response.Dest = GetMsg->Dest; /* final data destination in client memory space */          \
         if (verbose >= 2)                                                                          \
@@ -297,6 +301,7 @@ static void GetRequestHandler(CManager cm, CMConnection conn, void *vevent, void
         TotalGetBytesSent += Response.Size;                                                        \
         TotalGets++;                                                                               \
         CMwrite(conn, ev_state->ReadResponseFormat, &Response);                                    \
+        free(RetData);                                                                             \
     }
         ADIOS2_FOREACH_PRIMITIVE_STDTYPE_1ARG(GET)
 #undef GET
@@ -506,6 +511,20 @@ static bool server_timeout(void *CMvoid, int time_since_service)
     return false;
 }
 
+#define IMAX_BITS(m) ((m) / ((m) % 255 + 1) / 255 % 255 * 8 + 7 - 86 / ((m) % 255 + 12))
+#define RAND_MAX_WIDTH IMAX_BITS(RAND_MAX)
+
+uint64_t rand64(void)
+{
+    uint64_t r = 0;
+    for (int i = 0; i < 64; i += RAND_MAX_WIDTH)
+    {
+        r <<= RAND_MAX_WIDTH;
+        r ^= (unsigned)rand();
+    }
+    return r;
+}
+
 static void timer_start(void *param, unsigned int interval)
 {
 
@@ -542,6 +561,10 @@ int main(int argc, char **argv)
         {
             kill_server++;
         }
+        else if (strcmp(argv[i], "-report_port_selection") == 0)
+        {
+            report_port_selection++;
+        }
         else if (strcmp(argv[i], "-status") == 0)
         {
             status_server++;
@@ -580,7 +603,7 @@ int main(int argc, char **argv)
     }
     if (background)
     {
-        if (verbose)
+        if (verbose && !report_port_selection)
         {
             printf("Forking server to background\n");
         }
@@ -614,10 +637,29 @@ int main(int argc, char **argv)
         }
         exit(0);
 #else
+        parent_pid = getpid();
         if (fork() != 0)
         {
             /* I'm the parent, wait a sec to let the child start, then exit */
-            sleep(1);
+            //            sleep(1);
+            if (report_port_selection)
+            {
+                char final_filename[256];
+                snprintf(final_filename, sizeof(final_filename), "/tmp/port_file_%x", parent_pid);
+                FILE *f = NULL;
+                f = fopen(final_filename, "r");
+                while (f == NULL)
+                {
+                    sleep(1); // wait until available
+                    f = fopen(final_filename, "r");
+                }
+                char buffer[256];
+                fread(buffer, 1, 256, f);
+                printf("%s", buffer);
+            }
+            close(0);
+            close(1);
+            close(2);
             exit(0);
         }
         /* I'm the child, close IO FDs so that ctest continues.  No verbosity here */
@@ -652,15 +694,36 @@ int main(int argc, char **argv)
 
     if (listen_list == NULL)
         listen_list = create_attr_list();
-    add_attr(listen_list, CM_IP_PORT, Attr_Int4, (attr_value)ServerPort);
-    CMlisten_specific(cm, listen_list);
+    if (!report_port_selection)
+    {
+        // listen on well-known port
+        add_attr(listen_list, CM_IP_PORT, Attr_Int4, (attr_value)ServerPort);
+        CMlisten_specific(cm, listen_list);
+    }
+    else
+    {
+        // randomize port
+        CMlisten(cm);
+        listen_list = CMget_contact_list(cm);
+        int Port = -1;
+        get_int_attr(listen_list, CM_IP_PORT, &Port);
+        char filename[256];
+        char final_filename[256];
+        snprintf(filename, sizeof(filename), "/tmp/port_file_%x", getpid());
+        snprintf(final_filename, sizeof(final_filename), "/tmp/port_file_%x", parent_pid);
+        FILE *f = fopen(filename, "w");
+        random_cookie = rand64();
+        fprintf(f, "port:%d;msg:%s;cookie:%#018" PRIx64 "\n", Port, "no_error", random_cookie);
+        fclose(f);
+        rename(filename, final_filename);
+    }
 
     attr_list contact_list = CMget_contact_list(cm);
     if (contact_list)
     {
-        char *string_list = attr_list_to_string(contact_list);
-        std::cout << "Listening at port " << ServerPort << std::endl;
-        free(string_list);
+        int Port = -1;
+        get_int_attr(listen_list, CM_IP_PORT, &Port);
+        printf("Listening on Port %d\n", Port);
     }
     ev_state.cm = cm;