Implement message queue and test program.

diff --git a/Makefile.am b/Makefile.am
index 8b06456..4313667 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 DISTCHECK_CONFIGURE_FLAGS = \
        --with-systemdsystemunitdir=$$dc_install_base/$(systemdsystemunitdir)
-bin_PROGRAMS= tr/trust_router tr/trpc tid/example/tidc tid/example/tids common/dh_test/tr_dh_test trp/msgtst
+bin_PROGRAMS= tr/trust_router tr/trpc tid/example/tidc tid/example/tids common/dh_test/tr_dh_test common/mq_test/mq_test trp/msgtst
 AM_CPPFLAGS=-I$(srcdir)/include $(GLIB_CFLAGS)
 AM_CFLAGS = -Wall -Werror=missing-prototypes -Werror -Wno-parentheses $(GLIB_CFLAGS)
 SUBDIRS = gsscon 
@@ -69,6 +69,11 @@ common_dh_test_tr_dh_test_SOURCES = common/tr_dh.c \
 common/tr_debug.c \
 common/dh_test/dh_test.c
 
+common_mq_test_mq_test_SOURCES = common/tr_mq.c \
+common/mq_test/mq_test.c
+
+common_mq_test_mq_test_LDFLAGS = -pthread -ltalloc
+
 libtr_tid_la_SOURCES = tid/tids.c tid/tidc.c tid/tid_req.c tid/tid_resp.c \
 $(common_srcs)
 

diff --git a/common/mq_test/mq_test.c b/common/mq_test/mq_test.c
new file mode 100644 (file)
index 0000000..a833510
--- /dev/null
+++ b/common/mq_test/mq_test.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2016, JANET(UK)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of JANET(UK) nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include <tr_mq.h>
+
+static void notify_cb(TR_MQ *mq, void *arg)
+{
+  char *s=(char *)arg;
+
+  printf("MQ %s no longer empty.\n", s);
+}
+
+int main(void)
+{
+  TR_MQ *mq=NULL;
+  TR_MQ_MSG *msg=NULL;
+  TR_MQ_MSG *msg1=NULL;
+  TR_MQ_MSG *msg2=NULL;
+  TR_MQ_MSG *msg3=NULL;
+  TR_MQ_MSG *msg4=NULL;
+  char *mq_name="1";
+
+  mq=tr_mq_new(NULL);
+  mq->notify_cb=notify_cb;
+  mq->notify_cb_arg=mq_name;
+
+  msg1=tr_mq_msg_new(NULL);
+  asprintf((char **)&(msg1->p), "First message.\n");
+  msg1->p_free=free;
+  tr_mq_append(mq, msg1);
+  assert(mq->head==msg1);
+  assert(mq->tail==msg1);
+  assert(msg1->next==NULL);
+
+  msg2=tr_mq_msg_new(NULL);
+  asprintf((char **)&(msg2->p), "Second message.\n");
+  msg2->p_free=free;
+  tr_mq_append(mq, msg2);
+  assert(mq->head==msg1);
+  assert(msg1->next==msg2);
+  assert(mq->tail==msg2);
+  assert(msg2->next==NULL);
+
+  msg=tr_mq_pop(mq);
+  assert(msg==msg1);
+  assert(mq->head==msg2);
+  assert(mq->tail==msg2);
+  assert(msg2->next==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+  
+  msg3=tr_mq_msg_new(NULL);
+  asprintf((char **)&(msg3->p), "Third message.\n");
+  msg3->p_free=free;
+  tr_mq_append(mq, msg3);
+  assert(mq->head==msg2);
+  assert(mq->tail==msg3);
+  assert(msg2->next==msg3);
+  assert(msg3->next==NULL);
+
+  msg=tr_mq_pop(mq);
+  assert(msg==msg2);
+  assert(mq->head==msg3);
+  assert(mq->tail==msg3);
+  assert(msg3->next==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+  
+  msg=tr_mq_pop(mq);
+  assert(msg==msg3);
+  assert(mq->head==NULL);
+  assert(mq->tail==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+  
+  msg=tr_mq_pop(mq);
+  assert(msg==NULL);
+  assert(mq->head==NULL);
+  assert(mq->tail==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+
+  msg4=tr_mq_msg_new(NULL);
+  asprintf((char **)&(msg4->p), "Fourth message.\n");
+  msg4->p_free=free;
+  tr_mq_append(mq, msg4);
+  assert(mq->head==msg4);
+  assert(mq->tail==msg4);
+  assert(msg4->next==NULL);
+
+  msg=tr_mq_pop(mq);
+  assert(msg==msg4);
+  assert(mq->head==NULL);
+  assert(mq->tail==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+  
+  msg=tr_mq_pop(mq);
+  assert(msg==NULL);
+  assert(mq->head==NULL);
+  assert(mq->tail==NULL);
+  if ((msg!=NULL) && (msg->p!=NULL)) {
+    printf((char *)msg->p);
+    tr_mq_msg_free(msg);
+  } else
+    printf("no message to pop\n");
+
+  tr_mq_free(mq);
+
+  return 0;
+}

diff --git a/common/tr_mq.c b/common/tr_mq.c
new file mode 100644 (file)
index 0000000..c41a48c
--- /dev/null
+++ b/common/tr_mq.c
@@ -0,0 +1,94 @@
+#include <talloc.h>
+#include <pthread.h>
+
+#include <tr_mq.h>
+
+/* Messages */
+static int tr_mq_msg_destructor(void *object)
+{
+  TR_MQ_MSG *msg=talloc_get_type_abort(object, TR_MQ_MSG);
+  if ( (msg->p!=NULL) && (msg->p_free!=NULL))
+    msg->p_free(msg->p);
+  return 0;
+}
+
+TR_MQ_MSG *tr_mq_msg_new(TALLOC_CTX *mem_ctx)
+{
+  TR_MQ_MSG *msg=talloc(mem_ctx, TR_MQ_MSG);
+  if (msg!=NULL) {
+    msg->next=NULL;
+    msg->p=NULL;
+    talloc_set_destructor((void *)msg, tr_mq_msg_destructor);
+  }
+  return msg;
+}
+
+void tr_mq_msg_free(TR_MQ_MSG *msg)
+{
+  if (msg!=NULL)
+    talloc_free(msg);
+}
+
+/* Message Queues */
+TR_MQ *tr_mq_new(TALLOC_CTX *mem_ctx)
+{
+  TR_MQ *mq=talloc(mem_ctx, TR_MQ);
+  if (mq!=NULL) {
+    pthread_mutex_init(&(mq->lock), 0);
+    mq->head=NULL;
+    mq->tail=NULL;
+  }
+  return mq;
+}
+
+void tr_mq_free(TR_MQ *mq)
+{
+  if (mq!=NULL) {
+    pthread_mutex_lock(&(mq->lock)); /* don't pull this out from under someone */
+    talloc_free(mq);
+  }
+}
+
+/* puts msg in mq's talloc context */
+void tr_mq_append(TR_MQ *mq, TR_MQ_MSG *msg)
+{
+  int was_empty=FALSE;
+  TR_MQ_NOTIFY_FN notify_cb=NULL;
+  void *notify_cb_arg=NULL;
+
+  pthread_mutex_lock(&(mq->lock));
+  if (mq->head==NULL) {
+    was_empty=TRUE;
+    mq->head=mq->tail=msg;
+  } else {
+    mq->tail->next=msg; /* add to list */
+    mq->tail=msg; /* update tail of list */
+  }
+  talloc_steal(mq, msg);
+  /* before releasing the lock, get notify_cb data out of mq */
+  notify_cb=mq->notify_cb;
+  notify_cb_arg=mq->notify_cb_arg;
+  pthread_mutex_unlock(&(mq->lock));
+
+  /* see if we need to tell someone we became non-empty */
+  if (was_empty && (notify_cb!=NULL))
+    mq->notify_cb(mq, notify_cb_arg);
+}
+
+/* caller must free msg via tr_mq_msg_free */
+TR_MQ_MSG *tr_mq_pop(TR_MQ *mq)
+{
+  TR_MQ_MSG *popped=NULL;
+
+  pthread_mutex_lock(&(mq->lock));
+  if (mq->head!=NULL) {
+    popped=mq->head;
+    mq->head=mq->head->next;
+    if (mq->head==NULL)
+      mq->tail=NULL; /* just popped the last element */
+  }
+  pthread_mutex_unlock(&(mq->lock));
+  if (popped!=NULL)
+    popped->next=NULL; /* disconnect */
+  return popped;
+}