Changeset 1fcfc94 in mainline

Timestamp:

2009-03-02T17:35:03Z (15 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

6519d6f

Parents:

a32c9bb

Message:

add support for pending (blocking) connections to services
cleanup & cstyle

File:

• uspace/srv/ns/ns.c (modified) (18 diffs)

uspace/srv/ns/ns.c

@@ -29 +29 @@
 /** @addtogroup ns
  * @{
- */ 
+ */
 
 /**
- * @file        ns.c
- * @brief       Naming service for HelenOS IPC.
+ * @file  ns.c
+ * @brief Naming service for HelenOS IPC.
  */
 
@@ -53 +53 @@
 #include <as.h>
 
-#define NAME    "ns"
-
-#define NS_HASH_TABLE_CHAINS    20
+#define NAME  "ns"
+
+#define NS_HASH_TABLE_CHAINS  20
 
 static int register_service(ipcarg_t service, ipcarg_t phone, ipc_call_t *call);
-static int connect_to_service(ipcarg_t service, ipc_call_t *call,
+static void connect_to_service(ipcarg_t service, ipc_call_t *call,
     ipc_callid_t callid);
 
@@ -65 +65 @@
 void connect_to_clonable(ipcarg_t service, ipc_call_t *call,
     ipc_callid_t callid);
+
 
 /* Static functions implementing NS hash table operations. */
@@ -84 +85 @@
 typedef struct {
         link_t link;
-        ipcarg_t service;               /**< Number of the service. */
-        ipcarg_t phone;                 /**< Phone registered with the service. */
-        ipcarg_t in_phone_hash;         /**< Incoming phone hash. */
+        ipcarg_t service;        /**< Number of the service. */
+        ipcarg_t phone;          /**< Phone registered with the service. */
+        ipcarg_t in_phone_hash;  /**< Incoming phone hash. */
 } hashed_service_t;
 
-static void *clockaddr = NULL;
-static void *klogaddr = NULL;
+/** Pending connection structure. */
+typedef struct {
+        link_t link;
+        ipcarg_t service;        /**< Number of the service. */
+        ipc_callid_t callid;     /**< Call ID waiting for the connection */
+        ipcarg_t arg2;           /**< Second argument */
+        ipcarg_t arg3;           /**< Third argument */
+} pending_req_t;
+
+static link_t pending_req;
 
 /** Request for connection to a clonable service. */
@@ -103 +112 @@
 static link_t cs_req;
 
+static void *clockaddr = NULL;
+static void *klogaddr = NULL;
+
 /** Return true if @a service is clonable. */
 static bool service_clonable(int service)
 {
-        return service == SERVICE_LOAD;
+        return (service == SERVICE_LOAD);
 }
 
@@ -129 +141 @@
 }
 
+/** Process pending connection requests */
+static void process_pending_req()
+{
+        link_t *cur;
+        
+loop:
+        for (cur = pending_req.next; cur != &pending_req; cur = cur->next) {
+                pending_req_t *pr = list_get_instance(cur, pending_req_t, link);
+                
+                unsigned long keys[3] = {
+                        pr->service,
+                        0,
+                        0
+                };
+                
+                link_t *link = hash_table_find(&ns_hash_table, keys);
+                if (!link)
+                        continue;
+                
+                hashed_service_t *hs = hash_table_get_instance(link, hashed_service_t, link);
+                ipcarg_t retval = ipc_forward_fast(pr->callid, hs->phone,
+                    pr->arg2, pr->arg3, 0, IPC_FF_NONE);
+                
+                if (!(pr->callid & IPC_CALLID_NOTIFICATION))
+                        ipc_answer_0(pr->callid, retval);
+                
+                list_remove(cur);
+                free(pr);
+                goto loop;
+        }
+}
+
 int main(int argc, char **argv)
 {
         printf(NAME ": HelenOS IPC Naming Service\n");
         
-        ipc_call_t call;
-        ipc_callid_t callid;
-        
-        ipcarg_t retval;
-
         if (!hash_table_create(&ns_hash_table, NS_HASH_TABLE_CHAINS, 3,
             &ns_hash_table_ops)) {
-                printf(NAME ": No memory available\n");
+                printf(NAME ": No memory available for services\n");
                 return ENOMEM;
         }
-
+        
+        list_initialize(&pending_req);
         list_initialize(&cs_req);
         
         printf(NAME ": Accepting connections\n");
-        while (1) {
-                callid = ipc_wait_for_call(&call);
+        while (true) {
+                process_pending_req();
+                
+                ipc_call_t call;
+                ipc_callid_t callid = ipc_wait_for_call(&call);
+                ipcarg_t retval;
+                
                 switch (IPC_GET_METHOD(call)) {
                 case IPC_M_SHARE_IN:
@@ -187 +232 @@
                                 continue;
                         } else {
-                                retval = connect_to_service(IPC_GET_ARG1(call),
-                                    &call, callid);
+                                connect_to_service(IPC_GET_ARG1(call), &call,
+                                    callid);
+                                continue;
                         }
                         break;
@@ -195 +241 @@
                         break;
                 }
-                if (!(callid & IPC_CALLID_NOTIFICATION)) {
+                
+                if (!(callid & IPC_CALLID_NOTIFICATION))
                         ipc_answer_0(callid, retval);
-                }
         }
         
@@ -206 +252 @@
 /** Register service.
  *
- * @param service       Service to be registered.
- * @param phone         Phone to be used for connections to the service.
- * @param call          Pointer to call structure.
- *
- * @return              Zero on success or a value from @ref errno.h.
+ * @param service Service to be registered.
+ * @param phone   Phone to be used for connections to the service.
+ * @param call    Pointer to call structure.
+ *
+ * @return Zero on success or a value from @ref errno.h.
+ *
  */
 int register_service(ipcarg_t service, ipcarg_t phone, ipc_call_t *call)
@@ -219 +266 @@
                 0
         };
-        hashed_service_t *hs;
-
-        if (hash_table_find(&ns_hash_table, keys)) {
+        
+        if (hash_table_find(&ns_hash_table, keys))
                 return EEXISTS;
-        }
-                        
-        hs = (hashed_service_t *) malloc(sizeof(hashed_service_t));
-        if (!hs) {
+        
+        hashed_service_t *hs = (hashed_service_t *) malloc(sizeof(hashed_service_t));
+        if (!hs)
                 return ENOMEM;
-        }
-                        
+        
         link_initialize(&hs->link);
         hs->service = service;
@@ -235 +279 @@
         hs->in_phone_hash = call->in_phone_hash;
         hash_table_insert(&ns_hash_table, keys, &hs->link);
+        
+        return 0;
+}
+
+/** Connect client to service.
+ *
+ * @param service Service to be connected to.
+ * @param call    Pointer to call structure.
+ * @param callid  Call ID of the request.
+ *
+ * @return Zero on success or a value from @ref errno.h.
+ *
+ */
+void connect_to_service(ipcarg_t service, ipc_call_t *call, ipc_callid_t callid)
+{
+        ipcarg_t retval;
+        unsigned long keys[3] = {
+                service,
+                0,
+                0
+        };
+        
+        link_t *link = hash_table_find(&ns_hash_table, keys);
+        if (!link) {
+                if (IPC_GET_ARG4(*call) & IPC_FLAG_BLOCKING) {
+                        /* Blocking connection, add to pending list */
+                        pending_req_t *pr = (pending_req_t *) malloc(sizeof(pending_req_t));
+                        if (!pr) {
+                                retval = ENOMEM;
+                                goto out;
+                        }
                         
-        return 0;
-}
-
-/** Connect client to service.
- *
- * @param service       Service to be connected to.
- * @param call          Pointer to call structure.
- * @param callid        Call ID of the request.
- *
- * @return Zero on success or a value from @ref errno.h.
- */
-int connect_to_service(ipcarg_t service, ipc_call_t *call, ipc_callid_t callid)
-{
-        unsigned long keys[3] = { service, 0, 0 };
-        link_t *hlp;
-        hashed_service_t *hs;
-
-        hlp = hash_table_find(&ns_hash_table, keys);
-        if (!hlp) {
-                return ENOENT;
-        }
-        hs = hash_table_get_instance(hlp, hashed_service_t, link);
-        return ipc_forward_fast(callid, hs->phone, IPC_GET_ARG2(*call), 
-                IPC_GET_ARG3(*call), 0, IPC_FF_NONE);
+                        pr->service = service;
+                        pr->callid = callid;
+                        pr->arg2 = IPC_GET_ARG2(*call);
+                        pr->arg3 = IPC_GET_ARG3(*call);
+                        list_append(&pr->link, &pending_req);
+                        return;
+                }
+                retval = ENOENT;
+                goto out;
+        }
+        
+        hashed_service_t *hs = hash_table_get_instance(link, hashed_service_t, link);
+        retval = ipc_forward_fast(callid, hs->phone, IPC_GET_ARG2(*call),
+            IPC_GET_ARG3(*call), 0, IPC_FF_NONE);
+        
+out:
+        if (!(callid & IPC_CALLID_NOTIFICATION))
+                ipc_answer_0(callid, retval);
 }
 
 /** Register clonable service.
  *
- * @param service       Service to be registered.
- * @param phone         Phone to be used for connections to the service.
- * @param call          Pointer to call structure.
+ * @param service Service to be registered.
+ * @param phone   Phone to be used for connections to the service.
+ * @param call    Pointer to call structure.
+ *
  */
 void register_clonable(ipcarg_t service, ipcarg_t phone, ipc_call_t *call,
     ipc_callid_t callid)
 {
-        int rc;
-        cs_req_t *csr;
-
         if (list_empty(&cs_req)) {
                 /* There was no pending connection request. */
@@ -280 +347 @@
                 return;
         }
-
-        csr = list_get_instance(cs_req.next, cs_req_t, link);
+        
+        cs_req_t *csr = list_get_instance(cs_req.next, cs_req_t, link);
         list_remove(&csr->link);
-
+        
         /* Currently we can only handle a single type of clonable service. */
         assert(csr->service == SERVICE_LOAD);
-
+        
         ipc_answer_0(callid, EOK);
-
-        rc = ipc_forward_fast(csr->callid, phone, IPC_GET_ARG2(csr->call),
+        
+        int rc = ipc_forward_fast(csr->callid, phone, IPC_GET_ARG2(csr->call),
                 IPC_GET_ARG3(csr->call), 0, IPC_FF_NONE);
-
+        
         free(csr);
 }
@@ -297 +364 @@
 /** Connect client to clonable service.
  *
- * @param service       Service to be connected to.
- * @param call          Pointer to call structure.
- * @param callid        Call ID of the request.
- *
- * @return              Zero on success or a value from @ref errno.h.
+ * @param service Service to be connected to.
+ * @param call    Pointer to call structure.
+ * @param callid  Call ID of the request.
+ *
+ * @return Zero on success or a value from @ref errno.h.
+ *
  */
 void connect_to_clonable(ipcarg_t service, ipc_call_t *call,
     ipc_callid_t callid)
 {
-        int rc;
-        cs_req_t *csr;
-
         assert(service == SERVICE_LOAD);
-
-        csr = malloc(sizeof(cs_req_t));
+        
+        cs_req_t *csr = malloc(sizeof(cs_req_t));
         if (csr == NULL) {
                 ipc_answer_0(callid, ENOMEM);
                 return;
         }
-
+        
         /* Spawn a loader. */
-        rc = loader_spawn("loader");
-
+        int rc = loader_spawn("loader");
+        
         if (rc < 0) {
                 free(csr);
@@ -325 +390 @@
                 return;
         }
-
+        
         csr->service = service;
         csr->call = *call;
         csr->callid = callid;
-
+        
         /*
          * We can forward the call only after the server we spawned connects
@@ -341 +406 @@
  *
  * @param key Pointer keys. However, only the first key (i.e. service number)
- *            is used to compute the hash index.
+ *            is used to compute the hash index.
+ *
  * @return Hash index corresponding to key[0].
+ *
  */
 hash_index_t ns_hash(unsigned long *key)
 {
         assert(key);
-        return *key % NS_HASH_TABLE_CHAINS;
+        return (*key % NS_HASH_TABLE_CHAINS);
 }
 
@@ -358 +425 @@
  * as a nasty hack.
  *
- * @param key Array of keys.
+ * @param key  Array of keys.
  * @param keys Must be lesser or equal to 3.
  * @param item Pointer to a hash table item.
+ *
  * @return Non-zero if the key matches the item, zero otherwise.
+ *
  */
 int ns_compare(unsigned long key[], hash_count_t keys, link_t *item)
 {
-        hashed_service_t *hs;
-
         assert(key);
         assert(keys <= 3);
         assert(item);
         
-        hs = hash_table_get_instance(item, hashed_service_t, link);
+        hashed_service_t *hs = hash_table_get_instance(item, hashed_service_t, link);
         
         if (keys == 2)
@@ -382 +449 @@
  *
  * @param item Item that was removed from the hash table.
+ *
  */
 void ns_remove(link_t *item)
@@ -389 +457 @@
 }
 
-/** 
+/**
  * @}
  */