Merge pull request #14 from ifakhrutdinov/feature/cms-status-check

Add a core service that returns status information.

c/crossmemory.c

@@ -65,6 +65,7 @@ const CrossMemoryServerName CMS_DEFAULT_SERVER_NAME = {CROSS_MEMORY_DEFAULT_SERV
 #define CROSS_MEMORY_SERVER_LOG_SERVICE_ID    1
 #define CROSS_MEMORY_SERVER_DUMP_SERVICE_ID   2
 #define CROSS_MEMORY_SERVER_CONFIG_SERVICE_ID 3
+#define CROSS_MEMORY_SERVER_STATUS_SERVICE_ID 4
 
 #define TOSTR(number) #number
 #define INT_TO_STR(number) TOSTR(number)
@@ -76,7 +77,8 @@ const char *CMS_RC_DESCRIPTION[] = {
   [RC_CMS_SERVER_ABENDED] = "Cross-memory call ABENDed",
   [RC_CMS_WRONG_SERVER_VERSION] = "Wrong server version",
   [RC_CMS_WRONG_CLIENT_VERSION] = "Wrong client version",
-  [RC_CMS_MAX_RC] = NULL
+  [RC_CMS_SERVER_NAME_NULL] = "Server name is NULL",
+  [RC_CMS_MAX_RC + 1] = NULL
 };
 
 #define CMS_DDNAME  "STEPLIB "
@@ -1996,6 +1998,9 @@ static int handleStandardService(CrossMemoryServer *server, CrossMemoryServerPar
   case CROSS_MEMORY_SERVER_CONFIG_SERVICE_ID:
     status = handleConfigService(server, localParmList->callerData);
     break;
+  case CROSS_MEMORY_SERVER_STATUS_SERVICE_ID:
+    status = RC_CMS_OK;
+    break;
   }
 
   return status;
@@ -2372,6 +2377,13 @@ static void initStandardServices(CrossMemoryServer *server) {
   configService->flags |= CROSS_MEMORY_SERVICE_FLAG_INITIALIZED;
   configService->flags |= CROSS_MEMORY_SERVICE_FLAG_SPACE_SWITCH;
 
+  /* status service */
+  CrossMemoryService *statusService =
+      &server->serviceTable[CROSS_MEMORY_SERVER_STATUS_SERVICE_ID];
+  statusService->function = NULL;
+  statusService->flags |= CROSS_MEMORY_SERVICE_FLAG_INITIALIZED;
+  statusService->flags |= CROSS_MEMORY_SERVICE_FLAG_SPACE_SWITCH;
+
 }
 
 static void termStandardServices(CrossMemoryServer *server) {
@@ -4158,6 +4170,11 @@ int cmsGetGlobalArea(const CrossMemoryServerName *serverName, CrossMemoryServerG
     if (globalAreaCandidate != NULL) {
       if (memcmp(&globalAreaCandidate->serverName, serverName, sizeof(CrossMemoryServerName)) == 0 &&
           globalAreaCandidate->version == CROSS_MEMORY_SERVER_VERSION) {
+        /* TODO: make a new function that finds a running server by name
+         * The version check should be done when we've found a running instance,
+         * otherwise it is not clear whether global are is NULL because it's
+         * not been allocated or the caller's and server's versions don't
+         * match. */
         globalArea = globalAreaCandidate;
         break;
       }
@@ -4226,6 +4243,10 @@ static int callServiceInternal(CrossMemoryServerGlobalArea *globalArea, int serv
 
 int cmsCallService(const CrossMemoryServerName *serverName, int serviceID, void *parmList, int *serviceRC) {
 
+  if (serverName == NULL) {
+    return RC_CMS_SERVER_NAME_NULL;
+  }
+
   if (serviceID <= 0 || CROSS_MEMORY_SERVER_MAX_SERVICE_ID < serviceID) {
     return RC_CMS_FUNCTION_ID_OUT_OF_RANGE;
   }
@@ -4318,6 +4339,37 @@ CrossMemoryServerName cmsMakeServerName(const char *nameNullTerm) {
   return name;
 }
 
+static void fillServerStatus(int cmsRC, CrossMemoryServerStatus *status) {
+
+  memset(status, 0, sizeof(CrossMemoryServerStatus));
+
+  const char *description = NULL;
+  if (0 <= cmsRC && cmsRC <= RC_CMS_MAX_RC) {
+    description = CMS_RC_DESCRIPTION[cmsRC];
+  }
+
+  if (description == NULL) {
+    description = "N/A";
+  }
+
+  status->cmsRC = cmsRC;
+  strncpy(status->descriptionNullTerm, description,
+          sizeof(status->descriptionNullTerm) - 1);
+
+}
+
+CrossMemoryServerStatus cmsGetStatus(const CrossMemoryServerName *serverName) {
+
+  CrossMemoryServerStatus status = {0};
+
+  int cmsRC = cmsCallService(serverName, CROSS_MEMORY_SERVER_STATUS_SERVICE_ID,
+                             NULL, NULL);
+
+  fillServerStatus(cmsRC, &status);
+
+  return status;
+}
+
 #ifdef METTLE
 
 #define crossmemoryServerDESCTs CMSDSECT

h/crossmemory.h

@@ -125,7 +125,8 @@
 #define RC_CMS_NO_STEPLIB                   81
 #define RC_CMS_MODULE_NOT_IN_STEPLIB        82
 #define RC_CMS_ZVT_NOT_ALLOCATED            83
-#define RC_CMS_MAX_RC                       83
+#define RC_CMS_SERVER_NAME_NULL             84
+#define RC_CMS_MAX_RC                       84
 
 extern const char *CMS_RC_DESCRIPTION[];
 
@@ -355,6 +356,11 @@ typedef struct CrossMemoryServerConfigParm_tag {
   };
 } CrossMemoryServerConfigParm;
 
+typedef struct CrossMemoryServerStatus_tag {
+  int cmsRC;
+  char descriptionNullTerm[64];
+} CrossMemoryServerStatus;
+
 ZOWE_PRAGMA_PACK_RESET
 
 #define LOG_COMP_ID_CMS       0x008F000400010000LLU
@@ -379,6 +385,7 @@ ZOWE_PRAGMA_PACK_RESET
 #define cmsPrintf CMCMSPRF
 #define cmsGetConfigParm CMGETPRM
 #define cmsGetPCLogLevel CMGETLOG
+#define cmsGetStatus CMGETSTS
 #define cmsMakeServerName CMMKSNAM
 #define cmsAllocateECSAStorage CMECSAAL
 #define cmsFreeECSAStorage CMECSAFR
@@ -429,6 +436,7 @@ int cmsPrintf(const CrossMemoryServerName *serverName, const char *formatString,
 int cmsGetConfigParm(const CrossMemoryServerName *serverName, const char *name,
                      CrossMemoryServerConfigParm *parm);
 int cmsGetPCLogLevel(const CrossMemoryServerName *serverName);
+CrossMemoryServerStatus cmsGetStatus(const CrossMemoryServerName *serverName);
 CrossMemoryServerName cmsMakeServerName(const char *nameNullTerm);
 
 /* default message IDs (users of crossmemory.c can potentially redefine them) */