Added SDP negotiator and changed SDP structs (tested)

git-svn-id: http://svn.pjsip.org/repos/pjproject/trunk@129 74dad513-b988-da41-8d7b-12977e46ad98

5 files changed, 868 insertions, 167 deletions

diff --git a/pjmedia/include/pjmedia.h b/pjmedia/include/pjmedia.h
index b0310f24..7587b73e 100644
--- a/pjmedia/include/pjmedia.h
+++ b/pjmedia/include/pjmedia.h
@@ -19,14 +19,17 @@
 #ifndef __PJMEDIA_H__
 #define __PJMEDIA_H__
 
+#include <pjmedia/types.h>
+#include <pjmedia/errno.h>
 #include <pjmedia/codec.h>
 #include <pjmedia/jbuf.h>
 #include <pjmedia/mediamgr.h>
 #include <pjmedia/rtcp.h>
 #include <pjmedia/rtp.h>
-#include <pjmedia/session.h>
+//#include <pjmedia/session.h>
 #include <pjmedia/sound.h>
 #include <pjmedia/sdp.h>
+#include <pjmedia/sdp_neg.h>
 
 #endif	/* __PJMEDIA_H__ */
 
diff --git a/pjmedia/include/pjmedia/errno.h b/pjmedia/include/pjmedia/errno.h
new file mode 100644
index 00000000..1fe045e0
--- /dev/null
+++ b/pjmedia/include/pjmedia/errno.h
@@ -0,0 +1,250 @@
+/* $Id$ */
+/* 
+ * Copyright (C) 2003-2006 Benny Prijono <benny@prijono.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */
+#ifndef __PJMEDIA_ERRNO_H__
+#define __PJMEDIA_ERRNO_H__
+
+#include <pj/errno.h>
+
+PJ_BEGIN_DECL
+
+
+/**
+ * Guidelines on error message length.
+ */
+#define PJMEDIA_ERR_MSG_SIZE  64
+
+/**
+ * Get error message for the specified error code.
+ *
+ * @param status    The error code.
+ * @param buffer    The buffer where to put the error message.
+ * @param bufsize   Size of the buffer.
+ *
+ * @return	    The error message as NULL terminated string,
+ *                  wrapped with pj_str_t.
+ */
+PJ_DECL(pj_str_t) pjmedia_strerror( pj_status_t status, char *buffer,
+				    pj_size_t bufsize);
+
+
+/**
+ * Start of error code relative to PJ_ERRNO_START_USER.
+ */
+#define PJMEDIA_ERRNO_START       (PJ_ERRNO_START_USER + PJ_ERRNO_SPACE_SIZE)
+
+
+/************************************************************
+ * GENERIC/GENERAL PJMEDIA ERRORS
+ ***********************************************************/
+/**
+ * @hideinitializer
+ * General/unknown PJMEDIA error.
+ */
+#define PJMEDIA_ERROR		    (PJMEDIA_ERRNO_START+1)	/* 220001 */
+
+
+/************************************************************
+ * SDP ERRORS
+ ***********************************************************/
+/**
+ * @hideinitializer
+ * Generic invalid SDP descriptor.
+ */
+#define PJMEDIA_SDP_EINSDP	    (PJMEDIA_ERRNO_START+20)    /* 220020 */
+/**
+ * @hideinitializer
+ * Invalid SDP version.
+ */
+#define PJMEDIA_SDP_EINVER	    (PJMEDIA_ERRNO_START+21)    /* 220021 */
+/**
+ * @hideinitializer
+ * Invalid SDP origin (o=) line.
+ */
+#define PJMEDIA_SDP_EINORIGIN	    (PJMEDIA_ERRNO_START+22)    /* 220022 */
+/**
+ * @hideinitializer
+ * Invalid SDP time (t=) line.
+ */
+#define PJMEDIA_SDP_EINTIME	    (PJMEDIA_ERRNO_START+23)    /* 220023 */
+/**
+ * @hideinitializer
+ * Empty SDP subject/name (s=) line.
+ */
+#define PJMEDIA_SDP_EINNAME	    (PJMEDIA_ERRNO_START+24)    /* 220024 */
+/**
+ * @hideinitializer
+ * Invalid SDP connection info (c=) line.
+ */
+#define PJMEDIA_SDP_EINCONN	    (PJMEDIA_ERRNO_START+25)    /* 220025 */
+/**
+ * @hideinitializer
+ * Missing SDP connection info line.
+ */
+#define PJMEDIA_SDP_EMISSINGCONN    (PJMEDIA_ERRNO_START+26)    /* 220026 */
+/**
+ * @hideinitializer
+ * Invalid attribute (a=) line.
+ */
+#define PJMEDIA_SDP_EINATTR	    (PJMEDIA_ERRNO_START+27)    /* 220027 */
+/**
+ * @hideinitializer
+ * Invalid rtpmap attribute.
+ */
+#define PJMEDIA_SDP_EINRTPMAP	    (PJMEDIA_ERRNO_START+28)    /* 220028 */
+/**
+ * @hideinitializer
+ * rtpmap attribute is too long.
+ */
+#define PJMEDIA_SDP_ERTPMAPTOOLONG  (PJMEDIA_ERRNO_START+29)    /* 220029 */
+/**
+ * @hideinitializer
+ * rtpmap is missing for dynamic payload type.
+ */
+#define PJMEDIA_SDP_EMISSINGRTPMAP  (PJMEDIA_ERRNO_START+30)    /* 220030 */
+/**
+ * @hideinitializer
+ * Invalid SDP media (m=) line.
+ */
+#define PJMEDIA_SDP_EINMEDIA	    (PJMEDIA_ERRNO_START+31)    /* 220031 */
+/**
+ * @hideinitializer
+ * No payload format in the media stream.
+ */
+#define PJMEDIA_SDP_ENOFMT	    (PJMEDIA_ERRNO_START+32)    /* 220032 */
+/**
+ * @hideinitializer
+ * Invalid payload type in media.
+ */
+#define PJMEDIA_SDP_EINPT	    (PJMEDIA_ERRNO_START+33)    /* 220033 */
+/**
+ * @hideinitializer
+ * Invalid fmtp attribute.
+ */
+#define PJMEDIA_SDP_EINFMTP	    (PJMEDIA_ERRNO_START+34)    /* 220034 */
+
+
+/************************************************************
+ * SDP NEGOTIATOR ERRORS
+ ***********************************************************/
+/**
+ * @hideinitializer
+ * Invalid state to perform the specified operation.
+ */
+#define PJMEDIA_SDPNEG_EINSTATE	    (PJMEDIA_ERRNO_START+40)    /* 220040 */
+/**
+ * @hideinitializer
+ * No currently active SDP.
+ */
+#define PJMEDIA_SDPNEG_ENOACTIVE    (PJMEDIA_ERRNO_START+41)    /* 220041 */
+/**
+ * @hideinitializer
+ * Media count mismatch in offer and answer.
+ */
+#define PJMEDIA_SDPNEG_EMISMEDIA    (PJMEDIA_ERRNO_START+42)    /* 220042 */
+/**
+ * @hideinitializer
+ * Media type is different in the remote answer.
+ */
+#define PJMEDIA_SDPNEG_EINVANSMEDIA (PJMEDIA_ERRNO_START+43)    /* 220043 */
+/**
+ * @hideinitializer
+ * Transport type is different in the remote answer.
+ */
+#define PJMEDIA_SDPNEG_EINVANSTP    (PJMEDIA_ERRNO_START+44)    /* 220044 */
+/**
+ * @hideinitializer
+ * No common media payload is provided in the answer.
+ */
+#define PJMEDIA_SDPNEG_EANSNOMEDIA  (PJMEDIA_ERRNO_START+45)    /* 220045 */
+
+
+/************************************************************
+ * SDP COMPARISON STATUS
+ ***********************************************************/
+/**
+ * @hideinitializer
+ * SDP media stream not equal.
+ */
+#define PJMEDIA_SDP_EMEDIANOTEQUAL  (PJMEDIA_ERRNO_START+60)    /* 220060 */
+/**
+ * @hideinitializer
+ * Port number in SDP media descriptor not equal.
+ */
+#define PJMEDIA_SDP_EPORTNOTEQUAL   (PJMEDIA_ERRNO_START+61)    /* 220061 */
+/**
+ * @hideinitializer
+ * Transport in SDP media descriptor not equal.
+ */
+#define PJMEDIA_SDP_ETPORTNOTEQUAL  (PJMEDIA_ERRNO_START+62)    /* 220062 */
+/**
+ * @hideinitializer
+ * Media format in SDP media descriptor not equal.
+ */
+#define PJMEDIA_SDP_EFORMATNOTEQUAL (PJMEDIA_ERRNO_START+63)    /* 220063 */
+/**
+ * @hideinitializer
+ * SDP connection description not equal.
+ */
+#define PJMEDIA_SDP_ECONNNOTEQUAL   (PJMEDIA_ERRNO_START+64)    /* 220064 */
+/**
+ * @hideinitializer
+ * SDP attributes not equal.
+ */
+#define PJMEDIA_SDP_EATTRNOTEQUAL   (PJMEDIA_ERRNO_START+65)    /* 220065 */
+/**
+ * @hideinitializer
+ * SDP media direction not equal.
+ */
+#define PJMEDIA_SDP_EDIRNOTEQUAL    (PJMEDIA_ERRNO_START+66)    /* 220066 */
+/**
+ * @hideinitializer
+ * SDP fmtp attribute not equal.
+ */
+#define PJMEDIA_SDP_EFMTPNOTEQUAL   (PJMEDIA_ERRNO_START+67)    /* 220067 */
+/**
+ * @hideinitializer
+ * SDP ftpmap attribute not equal.
+ */
+#define PJMEDIA_SDP_ERTPMAPNOTEQUAL (PJMEDIA_ERRNO_START+68)    /* 220068 */
+/**
+ * @hideinitializer
+ * SDP session descriptor not equal.
+ */
+#define PJMEDIA_SDP_ESESSNOTEQUAL   (PJMEDIA_ERRNO_START+69)    /* 220069 */
+/**
+ * @hideinitializer
+ * SDP origin not equal.
+ */
+#define PJMEDIA_SDP_EORIGINNOTEQUAL (PJMEDIA_ERRNO_START+70)    /* 220070 */
+/**
+ * @hideinitializer
+ * SDP name/subject not equal.
+ */
+#define PJMEDIA_SDP_ENAMENOTEQUAL   (PJMEDIA_ERRNO_START+71)    /* 220071 */
+/**
+ * @hideinitializer
+ * SDP time not equal.
+ */
+#define PJMEDIA_SDP_ETIMENOTEQUAL   (PJMEDIA_ERRNO_START+72)    /* 220072 */
+
+
+PJ_END_DECL
+
+#endif	/* __PJMEDIA_ERRNO_H__ */
+
diff --git a/pjmedia/include/pjmedia/sdp.h b/pjmedia/include/pjmedia/sdp.h
index 1b45744c..71f00817 100644
--- a/pjmedia/include/pjmedia/sdp.h
+++ b/pjmedia/include/pjmedia/sdp.h
@@ -16,8 +16,8 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
  */
-#ifndef __PJSDP_SDP_H__
-#define __PJSDP_SDP_H__
+#ifndef __PJMEDIA_SDP_H__
+#define __PJMEDIA_SDP_H__
 
 /**
  * @defgroup PJSDP SDP Library
@@ -35,7 +35,7 @@
  * print back the structure as SDP message.
  */
 
-#include <pj/types.h>
+#include <pjmedia/types.h>
 
 PJ_BEGIN_DECL
 
@@ -43,160 +43,222 @@ PJ_BEGIN_DECL
 #define PJSDP_MAX_ATTR	32
 #define PJSDP_MAX_MEDIA	16
 
-/**
- * This enumeration describes the attribute type.
+
+/****************************************************************************
+ * SDP ATTRIBUTES
+ ****************************************************************************
+ */
+
+/** 
+ * SDP generic attribute.
  */
-typedef enum pjsdp_attr_type_e
+struct pjmedia_sdp_attr
 {
-    PJSDP_ATTR_RTPMAP,
-    PJSDP_ATTR_CAT,
-    PJSDP_ATTR_KEYWORDS,
-    PJSDP_ATTR_TOOL,
-    PJSDP_ATTR_PTIME,
-    PJSDP_ATTR_RECV_ONLY,
-    PJSDP_ATTR_SEND_ONLY,
-    PJSDP_ATTR_SEND_RECV,
-    PJSDP_ATTR_ORIENT,
-    PJSDP_ATTR_TYPE,
-    PJSDP_ATTR_CHARSET,
-    PJSDP_ATTR_SDP_LANG,
-    PJSDP_ATTR_LANG,
-    PJSDP_ATTR_FRAME_RATE,
-    PJSDP_ATTR_QUALITY,
-    PJSDP_ATTR_FMTP,
-    PJSDP_ATTR_INACTIVE,
-    PJSDP_ATTR_GENERIC,
-    PJSDP_END_OF_ATTR,
-} pjsdp_attr_type_e;
+    pj_str_t		name;	    /**< Attribute name.    */
+    pj_str_t		value;	    /**< Attribute value.   */
+};
 
 
 /**
- * This structure keeps the common attributes that all 'descendants' 
- * will have.
+ * Create SDP attribute.
+ *
+ * @param pool		Pool to create the attribute.
+ * @param name		Attribute name.
+ * @param value		Optional attribute value.
+ *
+ * @return		The new SDP attribute.
  */
-typedef struct pjsdp_attr
-{
-    pjsdp_attr_type_e	type;	/**< Attribute type. */
-} pjsdp_attr;
+PJ_DECL(pjmedia_sdp_attr*) pjmedia_sdp_attr_create(pj_pool_t *pool,
+						   const char *name,
+						   const pj_str_t *value);
 
+/** 
+ * Clone attribute 
+ *
+ * @param pool		Pool to be used.
+ * @param attr		The attribute to clone.
+ *
+ * @return		New attribute as cloned from the attribute.
+ */
+PJ_DECL(pjmedia_sdp_attr*) pjmedia_sdp_attr_clone(pj_pool_t *pool, 
+						  const pjmedia_sdp_attr*attr);
 
-/**
- * This is the structure to represent generic attribute which has a 
- * string value.
+/** 
+ * Find the first attribute with the specified type.
+ *
+ * @param count		Number of attributes in the array.
+ * @param attr_array	Array of attributes.
+ * @param name		Attribute name to find.
+ * @param fmt		Optional string to indicate which payload format
+ *			to find for rtpmap and fmt attributes.
+ *
+ * @return		The specified attribute, or NULL if it can't be found.
+ *
+ * @see pjmedia_sdp_attr_find2, pjmedia_sdp_media_find_attr
  */
-typedef struct pjsdp_attr_string
-{
-    pjsdp_attr_type_e	type;
-    pj_str_t		value;
-} pjsdp_attr_string;
+PJ_DECL(pjmedia_sdp_attr*) 
+pjmedia_sdp_attr_find(unsigned count, 
+		      const pjmedia_sdp_attr *const attr_array[],
+		      const pj_str_t *name, const pj_str_t *fmt);
 
+/** 
+ * Find the first attribute with the specified type.
+ *
+ * @param count		Number of attributes in the array.
+ * @param attr_array	Array of attributes.
+ * @param name		Attribute name to find.
+ * @param fmt		Optional string to indicate which payload format
+ *			to find for rtpmap and fmt attributes.
+ *
+ * @return		The specified attribute, or NULL if it can't be found.
+ *
+ * @see pjmedia_sdp_attr_find, pjmedia_sdp_media_find_attr2
+ */
+PJ_DECL(pjmedia_sdp_attr*) 
+pjmedia_sdp_attr_find2(unsigned count, 
+		       const pjmedia_sdp_attr *const attr_array[],
+		       const char *name, const pj_str_t *fmt);
 
 /**
- * This is the structure to represent generic SDP attribute which has
- * a numeric value.
+ * Add a new attribute to array of attributes.
+ *
+ * @param count		Number of attributes in the array.
+ * @param attr_array	Array of attributes.
+ * @param attr		The attribute to add.
+ *
+ * @return		PJ_SUCCESS or the error code.
+ *
+ * @see pjmedia_sdp_media_add_attr
  */
-typedef struct pjsdp_attr_num
-{
-    pjsdp_attr_type_e	type;
-    pj_uint32_t		value;
-} pjsdp_attr_num;
-
+PJ_DECL(pj_status_t) pjmedia_sdp_attr_add(unsigned *count,
+					  pjmedia_sdp_attr *attr_array[],
+					  pjmedia_sdp_attr *attr);
 
 /**
- * SDP \a rtpmap attribute.
+ * Remove all attributes with the specified name when they present.
+ *
+ * @param count		Number of attributes in the array.
+ * @param attr_array	Array of attributes.
+ * @param name		Attribute name to find.
+ *
+ * @return		Number of attributes removed.
+ *
+ * @see pjmedia_sdp_media_remove_all_attr
  */
-typedef struct pjsdp_rtpmap_attr
-{
-    pjsdp_attr_type_e	type;
-    unsigned		payload_type;
-    pj_str_t		encoding_name;
-    unsigned		clock_rate;
-    pj_str_t		parameter;
-} pjsdp_rtpmap_attr;
+PJ_DECL(unsigned) pjmedia_sdp_attr_remove_all(unsigned *count,
+					      pjmedia_sdp_attr *attr_array[],
+					      const char *name);
 
 
 /**
- * SDP \a fmtp attribute.
+ * Remove the specified attribute from the attribute array.
+ *
+ * @param count		Number of attributes in the array.
+ * @param attr_array	Array of attributes.
+ * @param name		Attribute name to find.
+ *
+ * @return		PJ_SUCCESS when attribute has been removed, or 
+ *			PJ_ENOTFOUND when the attribute can not be found.
+ *
+ * @see pjmedia_sdp_media_remove_attr
  */
-typedef struct pjsdp_fmtp_attr
-{
-    pjsdp_attr_type_e	type;
-    pj_str_t		format;
-    pj_str_t		param;
-} pjsdp_fmtp_attr;
+PJ_DECL(pj_status_t) pjmedia_sdp_attr_remove(unsigned *count,
+					     pjmedia_sdp_attr *attr_array[],
+					     pjmedia_sdp_attr *attr);
 
 
-/** 
- * SDP generic attribute.
+/**
+ * SDP \a rtpmap attribute.
  */
-typedef struct pjsdp_generic_attr
+struct pjmedia_sdp_rtpmap
 {
-    pjsdp_attr_type_e	type;
-    pj_str_t		name;
-    pj_str_t		value;
-} pjsdp_generic_attr;
-
-
-/** SDP \a cat attribute. */
-typedef struct pjsdp_attr_string pjsdp_cat_attr;
-
-/** SDP \a keywds attribute. */
-typedef struct pjsdp_attr_string pjsdp_keywds_attr;
-
-/** SDP \a tool attribute. */
-typedef struct pjsdp_attr_string pjsdp_tool_attr;
-
-/** SDP \a ptime attribute. */
-typedef struct pjsdp_attr_num pjsdp_ptime_attr;
+    pj_str_t		pt;	    /**< Payload type.	    */
+    pj_str_t		enc_name;   /**< Encoding name.	    */
+    unsigned		clock_rate; /**< Clock rate.	    */
+    pj_str_t		param;	    /**< Parameter.	    */
+};
 
-/** SDP \a recvonly attribute. */
-typedef struct pjsdp_attr pjsdp_recv_only_attr;
 
-/** SDP \a sendonly attribute. */
-typedef struct pjsdp_attr pjsdp_send_only_attr;
-
-/** SDP \a sendrecv attribute. */
-typedef struct pjsdp_attr pjsdp_send_recv_attr;
+/**
+ * Convert generic attribute to SDP rtpmap.
+ *
+ * @param pool		Pool used to create the rtpmap attribute.
+ * @param attr		Generic attribute to be converted to rtpmap, which
+ *			name must be "rtpmap".
+ * @param p_rtpmap	Pointer to receive SDP rtpmap attribute.
+ *
+ * @return		PJ_SUCCESS on success.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_attr_to_rtpmap(pj_pool_t *pool,
+						const pjmedia_sdp_attr *attr,
+						pjmedia_sdp_rtpmap **p_rtpmap);
 
-/** SDP \a orient attribute. */
-typedef struct pjsdp_attr_string pjsdp_orient_attr;
 
-/** SDP \a type attribute. */
-typedef struct pjsdp_attr_string pjsdp_type_attr;
+/**
+ * Get the rtpmap representation of the same SDP attribute.
+ *
+ * @param attr		Generic attribute to be converted to rtpmap, which
+ *			name must be "rtpmap".
+ * @param rtpmap	SDP rtpmap attribute to be initialized.
+ *
+ * @return		PJ_SUCCESS on success.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_attr_get_rtpmap(const pjmedia_sdp_attr *attr,
+						 pjmedia_sdp_rtpmap *rtpmap);
 
-/** SDP \a charset attribute. */
-typedef struct pjsdp_attr_string pjsdp_charset_attr;
 
-/** SDP \a sdplang attribute. */
-typedef struct pjsdp_attr_string pjsdp_sdp_lang_attr;
+/**
+ * Convert rtpmap attribute to generic attribute.
+ *
+ * @param pool		Pool to be used.
+ * @param rtpmap	The rtpmap attribute.
+ * @param p_attr	Pointer to receive the generic SDP attribute.
+ *
+ * @return		PJ_SUCCESS on success.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_rtpmap_to_attr(pj_pool_t *pool,
+						const pjmedia_sdp_rtpmap *rtpmap,
+						pjmedia_sdp_attr **p_attr);
 
-/** SDP \a lang attribute. */
-typedef struct pjsdp_attr_string pjsdp_lang_attr;
 
-/** SDP \a framerate attribute. */
-typedef struct pjsdp_attr_string pjsdp_frame_rate_attr;
+/**
+ * SDP \a fmtp attribute.
+ */
+struct pjmedia_sdp_fmtp
+{
+    pj_str_t		fmt;	    /**< Format type.		    */
+    pj_str_t		fmt_param;  /**< Format specific parameter. */
+};
 
-/** SDP \a quality attribute. */
-typedef struct pjsdp_attr_num pjsdp_quality_attr;
 
-/** SDP \a inactive attribute. */
-typedef struct pjsdp_attr pjsdp_inactive_attr;
+/**
+ * Get the fmtp representation of the same SDP attribute.
+ *
+ * @param attr		Generic attribute to be converted to fmtp, which
+ *			name must be "fmtp".
+ * @param fmtp		SDP fmtp attribute to be initialized.
+ *
+ * @return		PJ_SUCCESS on success.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_attr_get_fmtp(const pjmedia_sdp_attr *attr,
+					       pjmedia_sdp_fmtp *fmtp);
 
-/** Clone attribute */
-PJ_DECL(pjsdp_attr*) pjsdp_attr_clone (pj_pool_t *pool, const pjsdp_attr *rhs);
 
-/** Find attribute */
-PJ_DECL(const pjsdp_attr*) pjsdp_attr_find (int count, const pjsdp_attr *attr_array[], int type);
+/****************************************************************************
+ * SDP CONNECTION INFO
+ ****************************************************************************
+ */
 
 /**
  * SDP connection info.
  */
-typedef struct pjsdp_conn_info
+struct pjmedia_sdp_conn
 {
-    pj_str_t	net_type;
-    pj_str_t	addr_type;
-    pj_str_t	addr;
-} pjsdp_conn_info;
+    pj_str_t	net_type;	/**< Network type ("IN").		*/
+    pj_str_t	addr_type;	/**< Address type ("IP4", "IP6").	*/
+    pj_str_t	addr;		/**< The address.			*/
+};
+
 
 /** 
  *Clone connection info. 
@@ -206,29 +268,37 @@ typedef struct pjsdp_conn_info
  *
  * @return the new connection info.
  */
-PJ_DECL(pjsdp_conn_info*) pjsdp_conn_info_clone (pj_pool_t *pool, 
-						 const pjsdp_conn_info *rhs);
+PJ_DECL(pjmedia_sdp_conn*) pjmedia_sdp_conn_clone(pj_pool_t *pool, 
+						  const pjmedia_sdp_conn *rhs);
+
+
+
+/****************************************************************************
+ * SDP MEDIA INFO/LINE
+ ****************************************************************************
+ */
 
 /**
  * SDP media description.
  */
-typedef struct pjsdp_media_desc
+struct pjmedia_sdp_media
 {
     struct
     {
-	pj_str_t    media;
-	pj_uint16_t port;
-	unsigned    port_count;
-	pj_str_t    transport;
-	unsigned    fmt_count;
-	pj_str_t    fmt[PJSDP_MAX_FMT];
+	pj_str_t    media;		/**< Media type ("audio", "video")  */
+	pj_uint16_t port;		/**< Port number.		    */
+	unsigned    port_count;		/**< Port count, used only when >2  */
+	pj_str_t    transport;		/**< Transport ("RTP/AVP")	    */
+	unsigned    fmt_count;		/**< Number of formats.		    */
+	pj_str_t    fmt[PJSDP_MAX_FMT];	/**< Media formats.		    */
     } desc;
 
-    pjsdp_conn_info *conn;
-    unsigned	    attr_count;
-    pjsdp_attr	   *attr[PJSDP_MAX_ATTR];
+    pjmedia_sdp_conn *conn;		/**< Optional connection info.	    */
+    unsigned	     attr_count;	/**< Number of attributes.	    */
+    pjmedia_sdp_attr*attr[PJSDP_MAX_ATTR];  /**< Attributes.		    */
+
+};
 
-} pjsdp_media_desc;
 
 /** 
  * Clone SDP media description. 
@@ -238,63 +308,127 @@ typedef struct pjsdp_media_desc
  *
  * @return a new media description.
  */
-PJ_DECL(pjsdp_media_desc*) pjsdp_media_desc_clone (pj_pool_t *pool, 
-						   const pjsdp_media_desc *rhs);
+PJ_DECL(pjmedia_sdp_media*) 
+pjmedia_sdp_media_clone( pj_pool_t *pool, 
+			 const pjmedia_sdp_media *rhs);
 
-/** 
- * Check if the media description has the specified attribute.
+/**
+ * Find the first occurence of the specified attribute name.
  *
  * @param m		The SDP media description.
- * @param attr_type	The attribute type.
+ * @param name		Attribute name to find.
+ * @param fmt		Optional payload format type to find in the
+ *			attribute list. The payload format type will be
+ *			compared for attributes such as rtpmap and fmtp.
  *
- * @return nonzero if true.
+ * @return		The first instance of the specified attribute or NULL.
  */
-PJ_DECL(pj_bool_t) pjsdp_media_desc_has_attr (const pjsdp_media_desc *m, 
-					      pjsdp_attr_type_e attr_type);
+PJ_DECL(pjmedia_sdp_attr*) 
+pjmedia_sdp_media_find_attr(const pjmedia_sdp_media *m,
+			    const pj_str_t *name, const pj_str_t *fmt);
 
-/** 
- * Find rtpmap attribute for the specified payload type. 
+
+/**
+ * Find the first occurence of the specified attribute name.
+ *
+ * @param m		The SDP media description.
+ * @param name		Attribute name to find.
+ * @param fmt		Optional payload format type to find in the
+ *			attribute list. The payload format type will be
+ *			compared for attributes such as rtpmap and fmtp.
+ *
+ * @return		The first instance of the specified attribute or NULL.
+ */
+PJ_DECL(pjmedia_sdp_attr*) 
+pjmedia_sdp_media_find_attr2(const pjmedia_sdp_media *m,
+			     const char *name, const pj_str_t *fmt);
+
+/**
+ * Add new attribute to the media descriptor.
  *
- * @param m	    The SDP media description.
- * @param pt	    RTP payload type.
+ * @param m		The SDP media description.
+ * @param name		Attribute to add.
+ *
+ * @return		PJ_SUCCESS or the appropriate error code.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_media_add_attr(pjmedia_sdp_media *m,
+						pjmedia_sdp_attr *attr);
+
+/**
+ * Remove all attributes with the specified name.
+ *
+ * @param m		The SDP media description.
+ * @param name		Attribute name to remove.
  *
- * @return the SDP rtpmap attribute for the payload type, or NULL if not found.
+ * @return		The number of attributes removed.
+ */
+PJ_DECL(unsigned) 
+pjmedia_sdp_media_remove_all_attr(pjmedia_sdp_media *m,
+				  const char *name);
+
+
+/**
+ * Remove the occurence of the specified attribute.
+ */
+PJ_DECL(pj_status_t)
+pjmedia_sdp_media_remove_attr(pjmedia_sdp_media *m,
+			      pjmedia_sdp_attr *attr);
+
+
+/**
+ * Compare two SDP media for equality.
+ *
+ * @param sd1	    The first SDP media to compare.
+ * @param sd2	    The second SDP media to compare.
+ * @param option    Comparison option.
+ *
+ * @return	    PJ_SUCCESS when both SDP medias are equal.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_media_cmp(const pjmedia_sdp_media *sd1,
+					   const pjmedia_sdp_media *sd2,
+					   unsigned option);
+
+
+
+/****************************************************************************
+ * SDP SESSION DESCRIPTION
+ ****************************************************************************
  */
-PJ_DECL(const pjsdp_rtpmap_attr*) 
-pjsdp_media_desc_find_rtpmap (const pjsdp_media_desc *m, unsigned pt);
 
 
 /**
  * This structure describes SDP session description.
  */
-typedef struct pjsdp_session_desc
+struct pjmedia_sdp_session
 {
+    /** Origin (o= line) */
     struct
     {
-	pj_str_t    user;
-	pj_uint32_t id;
-	pj_uint32_t version;
-	pj_str_t    net_type;
-	pj_str_t    addr_type;
-	pj_str_t    addr;
+	pj_str_t    user;	    /**< User 				*/
+	pj_uint32_t id;		    /**< Session ID			*/
+	pj_uint32_t version;	    /**< Session version		*/
+	pj_str_t    net_type;	    /**< Network type ("IN")		*/
+	pj_str_t    addr_type;	    /**< Address type ("IP4", "IP6")	*/
+	pj_str_t    addr;	    /**< The address.			*/
     } origin;
 
-    pj_str_t	     name;
-    pjsdp_conn_info *conn;
+    pj_str_t	     name;	    /**< Subject line (s=)		*/
+    pjmedia_sdp_conn *conn;	    /**< Connection line (c=)		*/
     
+    /** Session time (t= line)	*/
     struct
     {
-	pj_uint32_t start;
-	pj_uint32_t stop;
+	pj_uint32_t start;	    /**< Start time.			*/
+	pj_uint32_t stop;	    /**< Stop time.			*/
     } time;
 
-    unsigned	    attr_count;
-    pjsdp_attr	   *attr[PJSDP_MAX_ATTR];
+    unsigned	       attr_count;		/**< Number of attributes.  */
+    pjmedia_sdp_attr  *attr[PJSDP_MAX_ATTR];	/**< Attributes array.	    */
 
-    unsigned	      media_count;
-    pjsdp_media_desc *media[PJSDP_MAX_MEDIA];
+    unsigned	       media_count;		/**< Number of media.	    */
+    pjmedia_sdp_media *media[PJSDP_MAX_MEDIA];	/**< Media array.	    */
 
-} pjsdp_session_desc;
+};
 
 
 /**
@@ -306,8 +440,9 @@ typedef struct pjsdp_session_desc
  *
  * @return SDP session description.
  */
-PJ_DECL(pjsdp_session_desc*) pjsdp_parse( char *buf, pj_size_t len, 
-					  pj_pool_t *pool);
+PJ_DECL(pj_status_t) pjmedia_sdp_parse( pj_pool_t *pool,
+				        char *buf, pj_size_t len, 
+					pjmedia_sdp_session **p_sdp );
 
 /**
  * Print SDP description to a buffer.
@@ -318,15 +453,47 @@ PJ_DECL(pjsdp_session_desc*) pjsdp_parse( char *buf, pj_size_t len,
  *
  * @return the length printed, or -1.
  */
-PJ_DECL(int) pjsdp_print( const pjsdp_session_desc *desc, 
-			  char *buf, pj_size_t size);
+PJ_DECL(int) pjmedia_sdp_print( const pjmedia_sdp_session *desc, 
+				char *buf, pj_size_t size);
 
 
 /**
- * @}
+ * Validate SDP descriptor.
  */
+PJ_DECL(pj_status_t) pjmedia_sdp_validate(const pjmedia_sdp_session *sdp);
+
+
+/**
+ * Clone SDP session.
+ *
+ * @param pool	    The pool used to clone the session.
+ * @param sess	    The SDP session to clone.
+ *
+ * @return	    New SDP session.
+ */
+PJ_DECL(pjmedia_sdp_session*) 
+pjmedia_sdp_session_clone( pj_pool_t *pool,
+			   const pjmedia_sdp_session *sess);
+
+
+/**
+ * Compare two SDP session for equality.
+ *
+ * @param sd1	    The first SDP session to compare.
+ * @param sd2	    The second SDP session to compare.
+ *
+ * @return	    PJ_SUCCESS when both SDPs are equal.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_session_cmp(const pjmedia_sdp_session *sd1,
+					     const pjmedia_sdp_session *sd2,
+					     unsigned option);
+
 
 PJ_END_DECL
 
-#endif	/* __PJSDP_SDP_H__ */
+/**
+ * @}
+ */
+
+#endif	/* __PJMEDIA_SDP_H__ */
 
diff --git a/pjmedia/include/pjmedia/sdp_neg.h b/pjmedia/include/pjmedia/sdp_neg.h
new file mode 100644
index 00000000..7d0cc086
--- /dev/null
+++ b/pjmedia/include/pjmedia/sdp_neg.h
@@ -0,0 +1,214 @@
+/* $Id$ */
+/* 
+ * Copyright (C) 2003-2006 Benny Prijono <benny@prijono.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */
+#ifndef __PJMEDIA_SDP_NEG_H__
+#define __PJMEDIA_SDP_NEG_H__
+
+
+/**
+ * @defgroup PJSDP SDP Library
+ */
+/**
+ * @file sdp_neg.h
+ * @brief SDP negotiator header file.
+ */
+/**
+ * @defgroup PJ_SDP_NEG SDP Negotiator.
+ * @ingroup PJSDP
+ * @{
+ *.
+ */
+
+#include <pjmedia/types.h>
+
+PJ_BEGIN_DECL
+
+/**
+ * This enumeration describes SDP negotiation state.
+ */
+enum pjmedia_sdp_neg_state
+{
+    /** 
+     * This is the state of SDP negoator before it is initialized. 
+     */
+    PJMEDIA_SDP_NEG_STATE_NULL,
+
+    /** 
+     * This state occurs when SDP negotiator has sent our offer to remote and
+     * it is waiting for answer.
+     */
+    PJMEDIA_SDP_NEG_STATE_LOCAL_OFFER,
+
+    /**
+     * This state occurs when an offer (either local or remote) has been 
+     * provided with answer. The SDP negotiator is ready to negotiate both
+     * session descriptors.
+     */
+    PJMEDIA_SDP_NEG_STATE_WAIT_NEGO,
+
+    /**
+     * This state occurs when SDP negotiation has completed, either 
+     * successfully or not.
+     */
+    PJMEDIA_SDP_NEG_STATE_DONE,
+};
+
+/* Negotiator state:
+ *
+ *                                                 reinit_local_offer()
+ *                                                 modify_local_offer()
+ *     create_w_local_offer()     +-------------+  tx_local_offer()
+ *     /------------------------->| LOCAL_OFFER |<----------------------\
+ *    |                           +-------------+                        |
+ *    |                                  |                               |
+ *    |               rx_remote_answer() |                               |
+ *    |                                  V                               |
+ * +--+---+                         +-----------+     negotiate()     +------+
+ * + NULL |------------------------>| WAIT_NEGO |-------------------->| DONE |
+ * +------+ create_w_remote_offer() +-----------+                     +------+
+ *                                       A                               |
+ *                                       |         rx_remote_offer()     |
+ *                                        \-----------------------------/
+ */ 
+
+/**
+ * Create the SDP negotiator with local offer. The SDP negotiator then
+ * will move to PJMEDIA_SDP_NEG_STATE_LOCAL_OFFER state, where it waits
+ * until it receives answer from remote. When SDP answer from remote is
+ * received, application should call #pjmedia_sdp_neg_rx_remote_answer().
+ *
+ * After calling this function, application should send the local SDP offer
+ * to remote party and wait for SDP answer.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_create_w_local_offer( pj_pool_t *pool,
+				      const pjmedia_sdp_session *local,
+				      pjmedia_sdp_neg **p_neg);
+
+/**
+ * Initialize the SDP negotiator with both local and remote offer. 
+ * Application normally calls this function when it receives initial offer
+ * from remote. Application must also provide initial local offer when
+ * calling this function. After this function is called, the SDP negotiator
+ * state will move to PJMEDIA_SDP_NEG_STATE_WAIT_NEGO, and the negotiation
+ * function can be called.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_create_w_remote_offer(pj_pool_t *pool,
+				      const pjmedia_sdp_session *local,
+				      const pjmedia_sdp_session *remote,
+				      pjmedia_sdp_neg **p_neg);
+
+/**
+ * Get SDP negotiator state.
+ */
+PJ_DECL(pjmedia_sdp_neg_state)
+pjmedia_sdp_neg_get_state( pjmedia_sdp_neg *neg );
+
+/**
+ * Get the currently active local SDP. Application can only call this
+ * function after negotiation has been done, or otherwise there won't be
+ * active SDPs. Calling this function will not change the state of the 
+ * negotiator.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_get_local( pjmedia_sdp_neg *neg,
+			   const pjmedia_sdp_session **local);
+
+/**
+ * Get the currently active remote SDP. Application can only call this
+ * function after negotiation has been done, or otherwise there won't be
+ * active SDPs. Calling this function will not change the state of the 
+ * negotiator.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_get_remote( pjmedia_sdp_neg *neg,
+			    const pjmedia_sdp_session **remote);
+
+
+/**
+ * Completely replaces local offer with new SDP. After calling
+ * This function can only be called in state PJMEDIA_SDP_NEG_STATE_DONE.
+ * this function, application can send the modified offer to remote.
+ * The negotiator state will move to PJMEDIA_SDP_NEG_STATE_LOCAL_OFFER,
+ * where it waits for SDP answer from remote.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_modify_local_offer( pj_pool_t *pool,
+				    pjmedia_sdp_neg *neg,
+				    const pjmedia_sdp_session *local);
+
+/**
+ * Negotiate local and remote answer. Before calling this function, the
+ * SDP negotiator must be in PJMEDIA_SDP_NEG_STATE_WAIT_NEGO state.
+ * After calling this function, the negotiator state will move to
+ * PJMEDIA_SDP_NEG_STATE_DONE.
+ */
+PJ_DECL(pj_status_t) pjmedia_sdp_neg_negotiate( pj_pool_t *pool,
+					        pjmedia_sdp_neg *neg,
+						pj_bool_t allow_asym);
+
+
+/**
+ * This function can only be called in PJMEDIA_SDP_NEG_STATE_DONE state.
+ * Application calls this function to retrieve currently active
+ * local SDP to be sent to remote. The negotiator state will then move
+ * to PJMEDIA_SDP_NEG_STATE_LOCAL_OFFER, where it waits for SDP answer
+ * from remote.
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_tx_local_offer( pj_pool_t *pool,
+			        pjmedia_sdp_neg *neg,
+				const pjmedia_sdp_session **offer);
+
+/**
+ * This function can only be called in PJMEDIA_SDP_NEG_STATE_DONE state. 
+ * Application calls this function when it receives SDP offer from remote.
+ * After this function is called, the negotiator state will move to 
+ * PJMEDIA_SDP_NEG_STATE_WAIT_NEGO, and application can call the
+ * negotiation function #pjmedia_sdp_neg_negotiate().
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_rx_remote_offer( pj_pool_t *pool,
+				 pjmedia_sdp_neg *neg,
+				 const pjmedia_sdp_session *remote);
+
+
+/**
+ * This function can only be called in PJMEDIA_SDP_NEG_STATE_LOCAL_OFFER
+ * state. Application calls this function when it receives SDP answer
+ * from remote. After this function is called, the negotiator state will
+ * move to PJMEDIA_SDP_NEG_STATE_WAIT_NEGO, and application can call the
+ * negotiation function #pjmedia_sdp_neg_negotiate().
+ */
+PJ_DECL(pj_status_t) 
+pjmedia_sdp_neg_rx_remote_answer( pj_pool_t *pool,
+				  pjmedia_sdp_neg *neg,
+				  const pjmedia_sdp_session *remote);
+
+
+
+PJ_END_DECL
+
+/**
+ * @}
+ */
+
+
+#endif	/* __PJMEDIA_SDP_NEG_H__ */
+
diff --git a/pjmedia/include/pjmedia/types.h b/pjmedia/include/pjmedia/types.h
new file mode 100644
index 00000000..217a001b
--- /dev/null
+++ b/pjmedia/include/pjmedia/types.h
@@ -0,0 +1,67 @@
+/* $Id$ */
+/* 
+ * Copyright (C) 2003-2006 Benny Prijono <benny@prijono.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */
+#ifndef __PJMEDIA_TYPES_H__
+#define __PJMEDIA_TYPES_H__
+
+#include <pj/types.h>
+
+
+/**
+ * Forward declaration for SDP attribute (sdp.h)
+ */
+typedef struct pjmedia_sdp_attr pjmedia_sdp_attr;
+
+/**
+ * Forward declaration for SDP rtpmap attribute (sdp.h)
+ */
+typedef struct pjmedia_sdp_rtpmap pjmedia_sdp_rtpmap;
+
+/**
+ * Forward declaration for SDP fmtp attribute (sdp.h)
+ */
+typedef struct pjmedia_sdp_fmtp pjmedia_sdp_fmtp;
+
+/**
+ * Forward declaration for SDP connection info (sdp.h)
+ */
+typedef struct pjmedia_sdp_conn pjmedia_sdp_conn;
+
+/**
+ * Forward declaration for SDP media line (sdp.h)
+ */
+typedef struct pjmedia_sdp_media pjmedia_sdp_media;
+
+/**
+ * Forward declaration for SDP session (sdp.h)
+ */
+typedef struct pjmedia_sdp_session pjmedia_sdp_session;
+
+/**
+ * Forward declaration for SDP negotiator state (sdp_neg.h).
+ */
+typedef enum pjmedia_sdp_neg_state pjmedia_sdp_neg_state;
+
+/**
+ * Forward declaration for SDP negotiator (sdp_neg.h).
+ */
+typedef struct pjmedia_sdp_neg pjmedia_sdp_neg;
+
+
+#endif	/* __PJMEDIA_TYPES_H__ */
+