--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/src/queue.c	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,292 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * queue.c - simple in process message queuing
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2004 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: queue.c,v 1.10 2006/11/19 14:07:25 steveu Exp $
+ */
+
+/*! \file */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <sys/types.h>
+
+#include <tiffio.h>
+
+#include "spandsp/queue.h"
+
+int queue_empty(queue_t *p)
+{
+    return (p->iptr == p->optr);
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_free_space(queue_t *p)
+{
+    if (p->iptr < p->optr)
+        return ((p->optr - p->iptr) - 1);
+    /*endif*/
+    return (p->len - (p->iptr - p->optr));
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_contents(queue_t *p)
+{
+    if (p->iptr < p->optr)
+        return (p->len - (p->optr - p->iptr) + 1);
+    /*endif*/
+    return (p->iptr - p->optr);
+}
+/*- End of function --------------------------------------------------------*/
+
+void queue_flush(queue_t *p)
+{
+    p->iptr =
+    p->optr = 0;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_view(queue_t *p, uint8_t *buf, int len)
+{
+    int real_len;
+    int to_end;
+
+    real_len = queue_contents(p);
+    if (real_len < len)
+    {
+        if (p->flags & QUEUE_READ_ATOMIC)
+            return -1;
+        /*endif*/
+    }
+    else
+    {
+        real_len = len;
+    }
+    /*endif*/
+    if (real_len == 0)
+        return 0;
+    /*endif*/
+    to_end = p->len + 1 - p->optr;
+    if (p->iptr < p->optr  &&  to_end < real_len)
+    {
+        /* A two step process */
+        if (buf)
+        {
+            memcpy(buf, p->data + p->optr, to_end);
+            memcpy(buf + to_end, p->data, real_len - to_end);
+        }
+        /*endif*/
+    }
+    else
+    {
+        /* A one step process */
+        if (buf)
+            memcpy(buf, p->data + p->optr, real_len);
+        /*endif*/
+    }
+    /*endif*/
+    return real_len;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_read(queue_t *p, uint8_t *buf, int len)
+{
+    int real_len;
+    int to_end;
+
+    real_len = queue_contents(p);
+    if (real_len < len)
+    {
+        if (p->flags & QUEUE_READ_ATOMIC)
+            return -1;
+        /*endif*/
+    }
+    else
+    {
+        real_len = len;
+    }
+    /*endif*/
+    if (real_len == 0)
+        return 0;
+    /*endif*/
+    to_end = p->len + 1 - p->optr;
+    if (p->iptr < p->optr  &&  to_end < real_len)
+    {
+        /* A two step process */
+        if (buf)
+        {
+            memcpy(buf, p->data + p->optr, to_end);
+            memcpy(buf + to_end, p->data, real_len - to_end);
+        }
+        /*endif*/
+        p->optr += (real_len - p->len + 1);
+    }
+    else
+    {
+        /* A one step process */
+        if (buf)
+            memcpy(buf, p->data + p->optr, real_len);
+        /*endif*/
+        p->optr += real_len;
+        if (p->optr > (p->len + 1))
+            p->optr = 0;
+        /*endif*/
+    }
+    /*endif*/
+    return real_len;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_write(queue_t *p, const uint8_t *buf, int len)
+{
+    int real_len;
+    int to_end;
+
+    real_len = queue_free_space(p);
+    if (real_len < len)
+    {
+        if (p->flags & QUEUE_WRITE_ATOMIC)
+            return -1;
+        /*endif*/
+    }
+    else
+    {
+        real_len = len;
+    }
+    /*endif*/
+    if (real_len == 0)
+        return 0;
+    /*endif*/
+    to_end = p->len + 1 - p->iptr;
+    if (p->iptr < p->optr  ||  to_end >= real_len)
+    {
+        /* A one step process */
+        memcpy(p->data + p->iptr, buf, real_len);
+        p->iptr += real_len;
+        if (p->iptr > (p->len + 1))
+            p->iptr = 0;
+        /*endif*/
+    }
+    else
+    {
+        /* A two step process */
+        memcpy(p->data + p->iptr, buf, to_end);
+        memcpy(p->data, buf + to_end, real_len - to_end);
+        p->iptr += (real_len - p->len + 1);
+    }
+    /*endif*/
+    return real_len;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_test_msg(queue_t *p)
+{
+    uint16_t lenx;
+
+    if (queue_view(p, (uint8_t *) &lenx, sizeof(uint16_t)) != sizeof(uint16_t))
+        return -1;
+    /*endif*/
+    return lenx;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_read_msg(queue_t *p, uint8_t *buf, int len)
+{
+    uint16_t lenx;
+
+    if (queue_read(p, (uint8_t *) &lenx, sizeof(uint16_t)) != sizeof(uint16_t))
+        return -1;
+    /*endif*/
+    if (lenx == 0)
+        return 0;
+    /*endif*/
+    if ((int) lenx > len)
+    {
+        len = queue_read(p, buf, len);
+        /* Discard the rest of the message */
+        queue_read(p, NULL, lenx - len);
+        return len;
+    }
+    /*endif*/
+    return queue_read(p, buf, lenx);
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_write_msg(queue_t *p, const uint8_t *buf, int len)
+{
+    uint16_t lenx;
+
+    if (queue_free_space(p) < (int) (len + sizeof(uint16_t)))
+        return 0;
+    /*endif*/
+    lenx = (uint16_t) len;
+    if (queue_write(p, (uint8_t *) &lenx, sizeof(uint16_t)) != sizeof(uint16_t))
+        return -1;
+    /*endif*/
+    if (len == 0)
+        return 0;
+    return queue_write(p, buf, len);
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_create(queue_t *p, int len, int flags)
+{
+    p->iptr =
+    p->optr = 0;
+    p->flags = flags;
+    p->len = len;
+    p->data = malloc(len + 1);
+    if (p->data == NULL)
+    {
+        p->flags = 0;
+        p->len = 0;
+        return -1;
+    }
+    /*endif*/
+    return 0;
+}
+/*- End of function --------------------------------------------------------*/
+
+int queue_delete(queue_t *p)
+{
+    p->flags = 0;
+    p->iptr =
+    p->optr = 0;
+    p->len = 0;
+    if (p->data)
+    {
+        free(p->data);
+        p->data = NULL;
+    }
+    return 0;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/