X-Git-Url: http://www.project-moonshot.org/gitweb/?p=trust_router.git;a=blobdiff_plain;f=tid%2Ftids.c;h=9b9d51f71d90dbb555cbbda477ae346aaea9b13b;hp=8d2274937a9e43be41748fa29db996f4ebe2dbd4;hb=3c5fb17459ff56d5e23cea059503f46a42150a1e;hpb=6e1647f2f4714d8c0c4c27ef376302bab1ae4bb3

diff --git a/tid/tids.c b/tid/tids.c
index 8d22749..9b9d51f 100644
--- a/tid/tids.c
+++ b/tid/tids.c
@@ -32,16 +32,13 @@
  *
  */
 
-#include <assert.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <string.h>
 #include <stdio.h>
-#include <errno.h>
 #include <sys/socket.h>
 #include <sys/wait.h>
-#include <netinet/in.h>
 #include <jansson.h>
 #include <talloc.h>
 #include <poll.h>
@@ -49,13 +46,23 @@
 #include <gsscon.h>
 #include <tr_debug.h>
 #include <tr_msg.h>
+#include <tr_socket.h>
+#include <tr_gss.h>
+#include <tr_event.h>
 
-static TID_RESP *tids_create_response (TIDS_INSTANCE *tids, TID_REQ *req) 
+/**
+ * Create a response with minimal fields filled in
+ *
+ * @param mem_ctx talloc context for the return value
+ * @param req request to respond to
+ * @return new response structure allocated in the mem_ctx context
+ */
+static TID_RESP *tids_create_response(TALLOC_CTX *mem_ctx, TID_REQ *req)
 {
   TID_RESP *resp=NULL;
   int success=0;
 
-  if (NULL == (resp = tid_resp_new(req))) {
+  if (NULL == (resp = tid_resp_new(mem_ctx))) {
     tr_crit("tids_create_response: Error allocating response structure.");
     return NULL;
   }
@@ -90,250 +97,137 @@ cleanup:
   return resp;
 }
 
-static int tids_listen(TIDS_INSTANCE *tids, int port, int *fd_out, size_t max_fd) 
-{
-  int rc = 0;
-  int conn = -1;
-  int optval = 1;
-  struct addrinfo *ai=NULL;
-  struct addrinfo *ai_head=NULL;
-  struct addrinfo hints={.ai_flags=AI_PASSIVE,
-                         .ai_family=AF_UNSPEC,
-                         .ai_socktype=SOCK_STREAM,
-                         .ai_protocol=IPPROTO_TCP};
-  char *port_str=NULL;
-  size_t n_opened=0;
-
-  tr_debug("tids_listen: started!");
-  port_str=talloc_asprintf(NULL, "%d", port);
-  if (port_str==NULL) {
-    tr_debug("tids_listen: unable to allocate port.");
-    return -1;
-  }
-
-  tr_debug("getaddrinfo()=%d", getaddrinfo(NULL, port_str, &hints, &ai_head));
-  talloc_free(port_str);
-  tr_debug("tids_listen: got address info");
-
-  /* TODO: listen on all ports */
-  for (ai=ai_head,n_opened=0; (ai!=NULL)&&(n_opened<max_fd); ai=ai->ai_next) {
-    if (0 > (conn = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol))) {
-      tr_debug("tids_listen: unable to open socket.");
-      continue;
-    }
-
-    optval=1;
-    if (0!=setsockopt(conn, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)))
-      tr_debug("tids_listen: unable to set SO_REUSEADDR."); /* not fatal? */
-
-    if (ai->ai_family==AF_INET6) {
-      /* don't allow IPv4-mapped IPv6 addresses (per RFC4942, not sure
-       * if still relevant) */
-      if (0!=setsockopt(conn, IPPROTO_IPV6, IPV6_V6ONLY, &optval, sizeof(optval))) {
-        tr_debug("tids_listen: unable to set IPV6_V6ONLY. Skipping interface.");
-        close(conn);
-        continue;
-      }
-    }
-
-    rc=bind(conn, ai->ai_addr, ai->ai_addrlen);
-    if (rc<0) {
-      tr_debug("tids_listen: unable to bind to socket.");
-      close(conn);
-      continue;
-    }
-
-    if (0>listen(conn, 512)) {
-      tr_debug("tids_listen: unable to listen on bound socket.");
-      close(conn);
-      continue;
-    }
-
-    /* ok, this one worked. Save it */
-    fd_out[n_opened++]=conn;
-  }
-  freeaddrinfo(ai_head);
-
-  if (n_opened==0) {
-    tr_debug("tids_listen: no addresses available for listening.");
-    return -1;
-  }
-
-  tr_debug("tids_listen: TRP Server listening on port %d on %d socket%s",
-           port,
-           n_opened,
-           (n_opened==1)?"":"s");
-
-  return n_opened;
-}
-
-/* returns EACCES if authorization is denied */
-static int tids_auth_cb(gss_name_t clientName, gss_buffer_t displayName,
-			void *data)
-{
-  struct tids_instance *inst = (struct tids_instance *) data;
-  TR_NAME name ={(char *) displayName->value,
-		 displayName->length};
-  int result=0;
-
-  if (0!=inst->auth_handler(clientName, &name, inst->cookie)) {
-    tr_debug("tids_auth_cb: client '%.*s' denied authorization.", name.len, name.buf);
-    result=EACCES; /* denied */
-  }
-
-  return result;
-}
-
-/* returns 0 on authorization success, 1 on failure, or -1 in case of error */
-static int tids_auth_connection (TIDS_INSTANCE *inst,
-				 int conn,
-                                 gss_ctx_id_t *gssctx)
-{
-  int rc = 0;
-  int auth, autherr = 0;
-  gss_buffer_desc nameBuffer = {0, NULL};
-  char *name = 0;
-  int nameLen = 0;
-
-  nameLen = asprintf(&name, "trustidentity@%s", inst->hostname);
-  nameBuffer.length = nameLen;
-  nameBuffer.value = name;
-
-  if (rc = gsscon_passive_authenticate(conn, nameBuffer, gssctx, tids_auth_cb, inst)) {
-    tr_debug("tids_auth_connection: Error from gsscon_passive_authenticate(), rc = %d.", rc);
-    free(name);
-    return -1;
-  }
-  free(name);
-  nameBuffer.value=NULL; nameBuffer.length=0;
-
-  if (rc = gsscon_authorize(*gssctx, &auth, &autherr)) {
-    tr_debug("tids_auth_connection: Error from gsscon_authorize, rc = %d, autherr = %d.", 
-	    rc, autherr);
-    return -1;
-  }
-
-  if (auth)
-    tr_debug("tids_auth_connection: Connection authenticated, conn = %d.", conn);
-  else
-    tr_debug("tids_auth_connection: Authentication failed, conn %d.", conn);
-
-  return !auth;
-}
-
-static int tids_read_request (TIDS_INSTANCE *tids, int conn, gss_ctx_id_t *gssctx, TR_MSG **mreq)
-{
-  int err;
-  char *buf;
-  size_t buflen = 0;
-
-  if (err = gsscon_read_encrypted_token(conn, *gssctx, &buf, &buflen)) {
-    if (buf)
-      free(buf);
-    return -1;
-  }
-
-  tr_debug("tids_read_request():Request Received, %u bytes.", (unsigned) buflen);
-
-  /* Parse request */
-  if (NULL == ((*mreq) = tr_msg_decode(buf, buflen))) {
-    tr_debug("tids_read_request():Error decoding request.");
-    free (buf);
-    return -1;
-  }
-
-  /* If this isn't a TID Request, just drop it. */
-  if (TID_REQUEST != (*mreq)->msg_type) {
-    tr_debug("tids_read_request(): Not a TID Request, dropped.");
-    return -1;
-  }
-
-  free (buf);
-  return buflen;
-}
-
-static int tids_handle_request (TIDS_INSTANCE *tids, TR_MSG *mreq, TID_RESP *resp) 
+static int tids_handle_request(TIDS_INSTANCE *tids, TID_REQ *req, TID_RESP *resp)
 {
   int rc=-1;
 
   /* Check that this is a valid TID Request.  If not, send an error return. */
-  if ((!tr_msg_get_req(mreq)) ||
-      (!tr_msg_get_req(mreq)->rp_realm) ||
-      (!tr_msg_get_req(mreq)->realm) ||
-      (!tr_msg_get_req(mreq)->comm)) {
+  if ((!req) ||
+      (!(req->rp_realm)) ||
+      (!(req->realm)) ||
+      (!(req->comm))) {
     tr_notice("tids_handle_request(): Not a valid TID Request.");
-    resp->result = TID_ERROR;
-    resp->err_msg = tr_new_name("Bad request format");
+    tid_resp_set_result(resp, TID_ERROR);
+    tid_resp_set_err_msg(resp, tr_new_name("Bad request format"));
     return -1;
   }
 
   tr_debug("tids_handle_request: adding self to req path.");
-  tid_req_add_path(tr_msg_get_req(mreq), tids->hostname, tids->tids_port);
+  tid_req_add_path(req, tids->hostname, tids->tids_port);
   
   /* Call the caller's request handler */
   /* TBD -- Handle different error returns/msgs */
-  if (0 > (rc = (*tids->req_handler)(tids, tr_msg_get_req(mreq), resp, tids->cookie))) {
+  if (0 > (rc = (*tids->req_handler)(tids, req, resp, tids->cookie))) {
     /* set-up an error response */
     tr_debug("tids_handle_request: req_handler returned error.");
-    resp->result = TID_ERROR;
-    if (!resp->err_msg)	/* Use msg set by handler, if any */
-      resp->err_msg = tr_new_name("Internal processing error");
-  }
-  else {
+    tid_resp_set_result(resp, TID_ERROR);
+    if (!tid_resp_get_err_msg(resp))	/* Use msg set by handler, if any */
+      tid_resp_set_err_msg(resp, tr_new_name("Internal processing error"));
+  } else {
     /* set-up a success response */
     tr_debug("tids_handle_request: req_handler returned success.");
-    resp->result = TID_SUCCESS;
+    tid_resp_set_result(resp, TID_SUCCESS);
     resp->err_msg = NULL;	/* No error msg on successful return */
   }
     
   return rc;
 }
 
+/**
+ * Produces a JSON-encoded msg containing the TID response
+ *
+ * @param mem_ctx talloc context for the return value
+ * @param resp outgoing response
+ * @return JSON-encoded message containing the TID response
+ */
+static char *tids_encode_response(TALLOC_CTX *mem_ctx, TID_RESP *resp)
+{
+  TR_MSG mresp;
+  char *resp_buf = NULL;
+
+  /* Construct the response message */
+  mresp.msg_type = TID_RESPONSE;
+  tr_msg_set_resp(&mresp, resp);
+
+  /* Encode the message to JSON */
+  resp_buf = tr_msg_encode(mem_ctx, &mresp);
+  if (resp_buf == NULL) {
+    tr_err("tids_encode_response: Error encoding json response.");
+    return NULL;
+  }
+  tr_debug("tids_encode_response: Encoded response: %s", resp_buf);
+
+  /* Success */
+  return resp_buf;
+}
+
+/**
+ * Encode/send an error response
+ *
+ * Part of the public interface
+ *
+ * @param tids
+ * @param req
+ * @param err_msg
+ * @return
+ */
 int tids_send_err_response (TIDS_INSTANCE *tids, TID_REQ *req, const char *err_msg) {
   TID_RESP *resp = NULL;
   int rc = 0;
 
+  if ((!tids) || (!req) || (!err_msg)) {
+    tr_debug("tids_send_err_response: Invalid parameters.");
+    return -1;
+  }
+
   /* If we already sent a response, don't send another no matter what. */
   if (req->resp_sent)
     return 0;
 
-  if (NULL == (resp = tids_create_response(tids, req))) {
+  if (NULL == (resp = tids_create_response(req, req))) {
     tr_crit("tids_send_err_response: Can't create response.");
     return -1;
   }
-  
+
   /* mark this as an error response, and include the error message */
   resp->result = TID_ERROR;
   resp->err_msg = tr_new_name((char *)err_msg);
   resp->error_path = req->path;
 
   rc = tids_send_response(tids, req, resp);
-  
+
   tid_resp_free(resp);
   return rc;
 }
 
+/**
+ * Encode/send a response
+ *
+ * Part of the public interface
+ *
+ * @param tids not actually used, but kept for ABI compatibility
+ * @param req
+ * @param resp
+ * @return
+ */
 int tids_send_response (TIDS_INSTANCE *tids, TID_REQ *req, TID_RESP *resp)
 {
   int err;
-  TR_MSG mresp;
   char *resp_buf;
 
-  if ((!tids) || (!req) || (!resp))
+  if ((!tids) || (!req) || (!resp)) {
     tr_debug("tids_send_response: Invalid parameters.");
+    return -1;
+  }
 
   /* Never send a second response if we already sent one. */
   if (req->resp_sent)
     return 0;
 
-  mresp.msg_type = TID_RESPONSE;
-  tr_msg_set_resp(&mresp, resp);
-
-  if (NULL == (resp_buf = tr_msg_encode(&mresp))) {
-
+  resp_buf = tids_encode_response(NULL, NULL);
+  if (resp_buf == NULL) {
     tr_err("tids_send_response: Error encoding json response.");
     tr_audit_req(req);
-
     return -1;
   }
 
@@ -344,12 +238,11 @@ int tids_send_response (TIDS_INSTANCE *tids, TID_REQ *req, TID_RESP *resp)
   tr_audit_resp(resp);
 
   /* Send the response over the connection */
-  if (err = gsscon_write_encrypted_token (req->conn, req->gssctx, resp_buf, 
-					  strlen(resp_buf) + 1)) {
+  err = gsscon_write_encrypted_token (req->conn, req->gssctx, resp_buf,
+                                            strlen(resp_buf) + 1);
+  if (err) {
     tr_notice("tids_send_response: Error sending response over connection.");
-
     tr_audit_req(req);
-
     return -1;
   }
 
@@ -361,83 +254,119 @@ int tids_send_response (TIDS_INSTANCE *tids, TID_REQ *req, TID_RESP *resp)
   return 0;
 }
 
-static void tids_handle_connection (TIDS_INSTANCE *tids, int conn)
+/**
+ * Callback to process a request and produce a response
+ *
+ * @param req_str JSON-encoded request
+ * @param data pointer to a TIDS_INSTANCE
+ * @return pointer to the response string or null to send no response
+ */
+static TR_MSG *tids_req_cb(TALLOC_CTX *mem_ctx, TR_MSG *mreq, void *data)
 {
-  TR_MSG *mreq = NULL;
+  TALLOC_CTX *tmp_ctx = talloc_new(NULL);
+  TIDS_INSTANCE *tids = talloc_get_type_abort(data, TIDS_INSTANCE);
+  TID_REQ *req = NULL;
   TID_RESP *resp = NULL;
+  TR_MSG *resp_msg = NULL; /* this is the return value */
   int rc = 0;
-  gss_ctx_id_t gssctx = GSS_C_NO_CONTEXT;
 
-  if (tids_auth_connection(tids, conn, &gssctx)) {
-    tr_notice("tids_handle_connection: Error authorizing TID Server connection.");
-    close(conn);
-    return;
+  /* If this isn't a TID Request, just drop it. */
+  if (mreq->msg_type != TID_REQUEST) {
+    tr_debug("tids_req_cb: Not a TID request, dropped.");
+    goto cleanup;
   }
 
-  tr_debug("tids_handle_connection: Connection authorized!");
+  /* Get a handle on the request itself. Don't free req - it belongs to mreq */
+  req = tr_msg_get_req(mreq);
 
-  while (1) {	/* continue until an error breaks us out */
+  /* Allocate a response message */
+  resp_msg = talloc(tmp_ctx, TR_MSG);
+  if (resp_msg == NULL) {
+    /* We cannot create a response message, so all we can really do is emit
+     * an error message and return. */
+    tr_crit("tids_req_cb: Error allocating response message.");
+    goto cleanup;
+  }
 
-    if (0 > (rc = tids_read_request(tids, conn, &gssctx, &mreq))) {
-      tr_debug("tids_handle_connection: Error from tids_read_request(), rc = %d.", rc);
-      return;
-    } else if (0 == rc) {
-      continue;
-    }
+  /* Allocate a response structure and populate common fields. Put it in the
+   * response message's talloc context. */
+  resp = tids_create_response(resp_msg, req);
+  if (resp == NULL) {
+    /* If we were unable to create a response, we cannot reply. Log an
+     * error if we can, then drop the request. */
+    tr_crit("tids_req_cb: Error creating response structure.");
+    resp_msg = NULL; /* the contents are in tmp_ctx, so they will still be cleaned up */
+    goto cleanup;
+  }
+  /* Now officially assign the response to the message. */
+  tr_msg_set_resp(resp_msg, resp);
+
+  /* Handle the request and fill in resp */
+  rc = tids_handle_request(tids, req, resp);
+  if (rc < 0) {
+    tr_debug("tids_req_cb: Error from tids_handle_request(), rc = %d.", rc);
+    /* Fall through, to send the response, either way */
+  }
 
-    /* Put connection information into the request structure */
-    tr_msg_get_req(mreq)->conn = conn;
-    tr_msg_get_req(mreq)->gssctx = gssctx;
-
-    /* Allocate a response structure and populate common fields */
-    if (NULL == (resp = tids_create_response (tids, tr_msg_get_req(mreq)))) {
-      tr_crit("tids_handle_connection: Error creating response structure.");
-      /* try to send an error */
-      tids_send_err_response(tids, tr_msg_get_req(mreq), "Error creating response.");
-      tr_msg_free_decoded(mreq);
-      return;
-    }
+  /* put the response message in the caller's context */
+  talloc_steal(mem_ctx, resp_msg);
 
-    if (0 > (rc = tids_handle_request(tids, mreq, resp))) {
-      tr_debug("tids_handle_connection: Error from tids_handle_request(), rc = %d.", rc);
-      /* Fall through, to send the response, either way */
-    }
+cleanup:
+  talloc_free(tmp_ctx);
+  return resp_msg;
+}
 
-    if (0 > (rc = tids_send_response(tids, tr_msg_get_req(mreq), resp))) {
-      tr_debug("tids_handle_connection: Error from tids_send_response(), rc = %d.", rc);
-      /* if we didn't already send a response, try to send a generic error. */
-      if (!tr_msg_get_req(mreq)->resp_sent)
-        tids_send_err_response(tids, tr_msg_get_req(mreq), "Error sending response.");
-      /* Fall through to free the response, either way. */
+static int tids_destructor(void *object)
+{
+  TIDS_INSTANCE *tids = talloc_get_type_abort(object, TIDS_INSTANCE);
+  if (tids->pids)
+    g_array_unref(tids->pids);
+  return 0;
+}
+
+TIDS_INSTANCE *tids_new(TALLOC_CTX *mem_ctx)
+{
+  TIDS_INSTANCE *tids = talloc_zero(mem_ctx, TIDS_INSTANCE);
+  if (tids) {
+    tids->pids = g_array_new(FALSE, FALSE, sizeof(struct tid_process));
+    if (tids->pids == NULL) {
+      talloc_free(tids);
+      return NULL;
     }
-    
-    tr_msg_free_decoded(mreq); /* takes resp with it */
-    return;
-  } 
+    talloc_set_destructor((void *)tids, tids_destructor);
+  }
+  return tids;
 }
 
-TIDS_INSTANCE *tids_create (void)
+/**
+ * Create a new TIDS instance
+ *
+ * Deprecated: exists for ABI compatibility, but tids_new() should be used instead
+ *
+ */
+TIDS_INSTANCE *tids_create(void)
 {
-  return talloc_zero(NULL, TIDS_INSTANCE);
+  return tids_new(NULL);
 }
 
 /* Get a listener for tids requests, returns its socket fd. Accept
  * connections with tids_accept() */
-int tids_get_listener(TIDS_INSTANCE *tids, 
-                      TIDS_REQ_FUNC *req_handler,
-                      tids_auth_func *auth_handler,
-                      const char *hostname,
-                      unsigned int port,
-                      void *cookie,
-                      int *fd_out,
-                      size_t max_fd)
+nfds_t tids_get_listener(TIDS_INSTANCE *tids,
+                         TIDS_REQ_FUNC *req_handler,
+                         tids_auth_func *auth_handler,
+                         const char *hostname,
+                         unsigned int port,
+                         void *cookie,
+                         int *fd_out,
+                         size_t max_fd)
 {
-  size_t n_fd=0;
-  size_t ii=0;
+  nfds_t n_fd = 0;
+  nfds_t ii = 0;
 
   tids->tids_port = port;
-  n_fd=tids_listen(tids, port, fd_out, max_fd);
-  if (n_fd<=0)
+  n_fd = tr_sock_listen_all(port, fd_out, max_fd);
+
+  if (n_fd == 0)
     tr_err("tids_get_listener: Error opening port %d");
   else {
     /* opening port succeeded */
@@ -451,13 +380,13 @@ int tids_get_listener(TIDS_INSTANCE *tids,
           close(fd_out[ii]);
           fd_out[ii]=-1;
         }
-        n_fd=0;
+        n_fd = 0;
         break;
       }
     }
   }
 
-  if (n_fd>0) {
+  if (n_fd > 0) {
     /* store the caller's request handler & cookie */
     tids->req_handler = req_handler;
     tids->auth_handler = auth_handler;
@@ -465,7 +394,7 @@ int tids_get_listener(TIDS_INSTANCE *tids,
     tids->cookie = cookie;
   }
 
-  return n_fd;
+  return (int)n_fd;
 }
 
 /* Accept and process a connection on a port opened with tids_get_listener() */
@@ -473,47 +402,137 @@ int tids_accept(TIDS_INSTANCE *tids, int listen)
 {
   int conn=-1;
   int pid=-1;
+  int pipe_fd[2];
+  struct tid_process tp = {0};
 
   if (0 > (conn = accept(listen, NULL, NULL))) {
     perror("Error from TIDS Server accept()");
     return 1;
   }
 
+  if (0 > pipe(pipe_fd)) {
+    perror("Error on pipe()");
+    return 1;
+  }
+  /* pipe_fd[0] is for reading, pipe_fd[1] is for writing */
+
   if (0 > (pid = fork())) {
     perror("Error on fork()");
     return 1;
   }
 
   if (pid == 0) {
+    close(pipe_fd[0]); /* child only writes */
     close(listen);
-    tids_handle_connection(tids, conn);
+    tr_gss_handle_connection(conn,
+                             "trustidentity", tids->hostname, /* acceptor name */
+                             tids->auth_handler, tids->cookie, /* auth callback and cookie */
+                             tids_req_cb, tids /* req callback and cookie */
+    );
+    if (write(pipe_fd[1], "OK\0", 3) < 0)
+      tr_crit("tids_accept: child process unable to write to pipe");
+    close(pipe_fd[1]);
     close(conn);
     exit(0); /* exit to kill forked child process */
-  } else {
-    close(conn);
   }
 
-  /* clean up any processes that have completed  (TBD: move to main loop?) */
-  while (waitpid(-1, 0, WNOHANG) > 0);
+  /* Only the parent process gets here */
+  close(pipe_fd[1]); /* parent only listens */
+  close(conn); /* connection belongs to the child */
+  tp.pid = pid;
+  tp.read_fd = pipe_fd[0];
+  g_array_append_val(tids->pids, tp); /* remember the PID of our child process */
 
+  /* clean up any processes that have completed */
+  tids_sweep_procs(tids);
   return 0;
 }
 
+/**
+ * Clean up any finished TID request processes
+ *
+ * This is called by the main process after forking each TID request. If you want to be
+ * sure finished processes are cleaned up promptly even during a lull in TID requests,
+ * this can be called from the main thread of the main process. It is not thread-safe,
+ * so should not be used from sub-threads. It should not be called by child processes -
+ * this would probably be harmless but ineffective.
+ *
+ * @param tids
+ */
+void tids_sweep_procs(TIDS_INSTANCE *tids)
+{
+  guint ii;
+  struct tid_process tp = {0};
+  char result[10] = {0};
+  ssize_t result_len;
+  int status;
+  int wait_rc;
+
+  /* loop backwards over the array so we can remove elements as we go */
+  for (ii=tids->pids->len; ii > 0; ii--) {
+    /* ii-1 is the current index - get our own copy, we may destroy the list's copy */
+    tp = g_array_index(tids->pids, struct tid_process, ii-1);
+
+    wait_rc = waitpid(tp.pid, &status, WNOHANG);
+    if (wait_rc == 0)
+      continue; /* process still running */
+
+    if (wait_rc < 0) {
+      /* invalid options will probably keep being invalid, report that condition */
+      if(errno == EINVAL)
+        tr_crit("tids_sweep_procs: waitpid called with invalid options");
+
+      /* If we got ECHILD, that means the PID was invalid; we'll assume the process was
+       * terminated and we missed it. For all other errors, move on
+       * to the next PID to check. */
+      if (errno != ECHILD)
+        continue;
+
+      tr_warning("tid_sweep_procs: TID process %d disappeared", tp.pid);
+    }
+
+    /* remove the item (we still have a copy of the data) */
+    g_array_remove_index_fast(tids->pids, ii-1); /* disturbs only indices >= ii-1 which we've already handled */
+
+    /* Report exit status unless we got ECHILD above or somehow waitpid returned the wrong pid */
+    if (wait_rc == tp.pid) {
+      if (WIFEXITED(status)) {
+        tr_debug("tids_sweep_procs: TID process %d exited with status %d.", tp.pid, WTERMSIG(status));
+      } else if (WIFSIGNALED(status)) {
+        tr_debug("tids_sweep_procs: TID process %d terminated by signal %d.", tp.pid, WTERMSIG(status));
+      }
+    } else if (wait_rc > 0) {
+      tr_err("tids_sweep_procs: waitpid returned pid %d, expected %d", wait_rc, tp.pid);
+    }
+
+    /* read the pipe - if the TID request worked, it will have written status before terminating */
+    result_len = read(tp.read_fd, result, sizeof(result)/sizeof(result[0]));
+    close(tp.read_fd);
+
+    if ((result_len > 0) && (strcmp(result, "OK") == 0)) {
+      tids->req_count++;
+      tr_debug("tids_sweep_procs: TID process %d succeeded", tp.pid);
+    } else {
+      tids->error_count++;
+      tr_debug("tids_sweep_procs: TID process %d failed", tp.pid);
+    }
+  }
+}
+
 /* Process tids requests forever. Should not return except on error. */
-#define MAX_SOCKETS 10
-int tids_start (TIDS_INSTANCE *tids, 
+int tids_start (TIDS_INSTANCE *tids,
                 TIDS_REQ_FUNC *req_handler,
                 tids_auth_func *auth_handler,
                 const char *hostname,
                 unsigned int port,
                 void *cookie)
 {
-  int fd[MAX_SOCKETS]={0};
-  size_t n_fd=0;
-  struct pollfd poll_fd[MAX_SOCKETS]={{0}};
+  int fd[TR_MAX_SOCKETS]={0};
+  nfds_t n_fd=0;
+  struct pollfd poll_fd[TR_MAX_SOCKETS]={{0}};
   int ii=0;
 
-  n_fd=tids_get_listener(tids, req_handler, auth_handler, hostname, port, cookie, fd, MAX_SOCKETS);
+  n_fd = tids_get_listener(tids, req_handler, auth_handler, hostname, port, cookie, fd, TR_MAX_SOCKETS);
   if (n_fd <= 0) {
     perror ("Error from tids_listen()");
     return 1;
@@ -557,7 +576,6 @@ int tids_start (TIDS_INSTANCE *tids,
 
   return 1;	/* should never get here, loops "forever" */
 }
-#undef MAX_SOCKETS
 
 void tids_destroy (TIDS_INSTANCE *tids)
 {