/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Contains implementation of various interfaces exported by library
 */

#include <stdio.h>
#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sdp.h>

#include "sdp_parse.h"
#include "commp_util.h"

#define FIELD_EQUALS_CRLF_LEN           4  /* first two characters and CRLF */

#define SDP_ATTR_TO_STR(m_attr) {                                       \
        while ((m_attr) != NULL) {                                      \
                if ((m_attr)->a_value != NULL) {                        \
                        wrote = snprintf(buf, len, "a=%s%c%s%s",        \
                            (m_attr)->a_name, COMMP_COLON, (m_attr)->   \
                            a_value, COMMP_CRLF);                       \
                } else {                                                \
                        wrote = snprintf(buf, len, "a=%s%s", (m_attr)-> \
                            a_name, COMMP_CRLF);                        \
                }                                                       \
                len = len - wrote;                                      \
                buf = buf + wrote;                                      \
                (m_attr) = (m_attr)->a_next;                            \
        }                                                               \
}

#define SDP_KEY_TO_STR(m_key) {                                         \
        if ((m_key) != NULL) {                                          \
                if ((m_key)->k_enckey != NULL) {                        \
                        wrote = snprintf(buf, len, "k=%s%c%s%s",        \
                            (m_key)->k_method, COMMP_COLON, (m_key)->   \
                            k_enckey, COMMP_CRLF);                      \
                } else {                                                \
                        wrote = snprintf(buf, len, "k=%s%s", (m_key)->  \
                            k_method, COMMP_CRLF);                      \
                }                                                       \
                len = len - wrote;                                      \
                buf = buf + wrote;                                      \
        }                                                               \
}

#define SDP_BANDWIDTH_TO_STR(m_bw) {                                    \
        while ((m_bw) != NULL) {                                        \
                wrote = snprintf(buf, len, "b=%s%c%llu%s", (m_bw)->     \
                    b_type, COMMP_COLON, (m_bw)->b_value, COMMP_CRLF);  \
                len = len - wrote;                                      \
                buf = buf + wrote;                                      \
                (m_bw) = (m_bw)->b_next;                                \
        }                                                               \
}

#define SDP_INFORMATION_TO_STR(m_info) {                                       \
        if ((m_info) != NULL) {                                                \
                wrote = snprintf(buf, len, "i=%s%s", (m_info), COMMP_CRLF);    \
                len = len - wrote;                                             \
                buf = buf + wrote;                                             \
        }                                                                      \
}

#define SDP_CONNECTION_TO_STR(m_conn) {                                        \
        while ((m_conn) != NULL) {                                             \
                if (strcasecmp((m_conn)->c_addrtype,                           \
                    COMMP_ADDRTYPE_IP4) == 0) {                                \
                        if ((m_conn)->c_addrcount > 1) {                       \
                                wrote = snprintf(buf, len, "c=%s %s %s/%d/%d"  \
                                    "%s", (m_conn)->c_nettype, (m_conn)->      \
                                    c_addrtype, (m_conn)->c_address, (m_conn)->\
                                    c_ttl, (m_conn)->c_addrcount, COMMP_CRLF); \
                        } else if ((m_conn)->c_addrcount == 1) {               \
                                wrote = snprintf(buf, len, "c=%s %s %s/%d%s",  \
                                    (m_conn)->c_nettype, (m_conn)->c_addrtype, \
                                    (m_conn)->c_address, (m_conn)->c_ttl,      \
                                    COMMP_CRLF);                               \
                        } else {                                               \
                                wrote = snprintf(buf, len, "c=%s %s %s%s",     \
                                    (m_conn)->c_nettype, (m_conn)->c_addrtype, \
                                    (m_conn)->c_address, COMMP_CRLF);          \
                        }                                                      \
                } else if (strcasecmp((m_conn)->c_addrtype,                    \
                    COMMP_ADDRTYPE_IP6) == 0) {                                \
                        if ((m_conn)->c_addrcount <= 1) {                      \
                                wrote = snprintf(buf, len, "c=%s %s %s%s",     \
                                    (m_conn)->c_nettype, (m_conn)->c_addrtype, \
                                    (m_conn)->c_address, COMMP_CRLF);          \
                        } else {                                               \
                                wrote = snprintf(buf, len, "c=%s %s %s/%d%s",  \
                                    (m_conn)->c_nettype, (m_conn)->c_addrtype, \
                                    (m_conn)->c_address, (m_conn)->c_addrcount,\
                                    COMMP_CRLF);                               \
                        }                                                      \
                } else {                                                       \
                        wrote = snprintf(buf, len, "c=%s %s %s%s", (m_conn)->  \
                            c_nettype, (m_conn)->c_addrtype, (m_conn)->        \
                            c_address, COMMP_CRLF);                            \
                }                                                              \
                len = len - wrote;                                             \
                buf = buf + wrote;                                             \
                (m_conn) = (m_conn)->c_next;                                   \
        }                                                                      \
}

#define SDP_ADD_KEY(d_key, s_key) {                                     \
        if ((s_key) != NULL) {                                          \
                if (sdp_add_key(&(d_key), (s_key)->k_method,            \
                    (s_key)->k_enckey) != 0) {                          \
                        sdp_free_session(new_sess);                     \
                        return (NULL);                                  \
                }                                                       \
        }                                                               \
}

#define SDP_ADD_ATTRIBUTE(d_attr, s_attr) {                             \
        while ((s_attr) != NULL) {                                      \
                if (sdp_add_attribute(&(d_attr), (s_attr)->a_name,      \
                    (s_attr)->a_value) != 0) {                          \
                        sdp_free_session(new_sess);                     \
                        return (NULL);                                  \
                }                                                       \
                (s_attr) = (s_attr)->a_next;                            \
        }                                                               \
}

#define SDP_ADD_BANDWIDTH(d_bw, s_bw) {                                 \
        while ((s_bw) != NULL) {                                        \
                if (sdp_add_bandwidth(&(d_bw), (s_bw)->b_type,          \
                    (s_bw)->b_value) != 0) {                            \
                        sdp_free_session(new_sess);                     \
                        return (NULL);                                  \
                }                                                       \
                (s_bw) = (s_bw)->b_next;                                \
        }                                                               \
}

#define SDP_ADD_CONNECTION(d_conn, s_conn) {                            \
        while ((s_conn) != NULL) {                                      \
                if (sdp_add_connection(&(d_conn), (s_conn)->c_nettype,  \
                    (s_conn)->c_addrtype, (s_conn)->c_address,          \
                    (s_conn)->c_ttl, (s_conn)->c_addrcount) != 0) {     \
                        sdp_free_session(new_sess);                     \
                        return (NULL);                                  \
                }                                                       \
                (s_conn) = (s_conn)->c_next;                            \
        }                                                               \
}

#define SDP_LEN_CONNECTION(m_conn) {                                      \
        while ((m_conn) != NULL) {                                        \
                len += FIELD_EQUALS_CRLF_LEN;                             \
                len += strlen((m_conn)->c_nettype);                       \
                len += strlen((m_conn)->c_addrtype) + 1;                  \
                len += strlen((m_conn)->c_address) + 1;                   \
                len += snprintf(buf, 1, "%u", (m_conn)->c_ttl) + 1;       \
                len += snprintf(buf, 1, "%d", (m_conn)->c_addrcount) + 1; \
                (m_conn) = (m_conn)->c_next;                              \
        }                                                                 \
}

#define SDP_LEN_BANDWIDTH(m_bw) {                                       \
        while ((m_bw) != NULL) {                                        \
                len += FIELD_EQUALS_CRLF_LEN;                           \
                len += strlen((m_bw)->b_type);                          \
                len += snprintf(buf, 1, "%llu", (m_bw)->b_value) + 1;   \
                (m_bw) = (m_bw)->b_next;                                \
        }                                                               \
}

#define SDP_LEN_KEY(m_key) {                                            \
        if ((m_key) != NULL) {                                          \
                len += FIELD_EQUALS_CRLF_LEN;                           \
                len += strlen((m_key)->k_method);                       \
                if ((m_key)->k_enckey != NULL)                          \
                        len += strlen((m_key)->k_enckey) + 1;           \
        }                                                               \
}

#define SDP_LEN_ATTRIBUTE(m_attr) {                                     \
        while ((m_attr) != NULL) {                                      \
                len += FIELD_EQUALS_CRLF_LEN;                           \
                len += strlen((m_attr)->a_name);                        \
                if ((m_attr)->a_value != NULL)                          \
                        len += strlen((m_attr)->a_value) + 1;           \
                (m_attr) = (m_attr)->a_next;                            \
        }                                                               \
}

/*
 * Given a media list and media name ("audio", "video", et al), it searches
 * the list for that media. Returns NULL if media not present.
 */
sdp_media_t *
sdp_find_media(sdp_media_t *media, const char *name)
{
        if (media == NULL || name == NULL || (strlen(name) == 0)) {
                return (NULL);
        }
        while (media != NULL) {
                if (media->m_name != NULL) {
                        if (strcasecmp(name, media->m_name) == 0)
                                return (media);
                }
                media = media->m_next;
        }
        return (media);
}

/*
 * Given a attribute list and name of the attribute ("rtpmap", "fmtp", et al),
 * this API searches the list for that attribute. Returns NULL if not found.
 */
sdp_attr_t *
sdp_find_attribute(sdp_attr_t *attr, const char *name)
{
        if (attr == NULL || name == NULL || (strlen(name) == 0)) {
                return (NULL);
        }
        while (attr != NULL) {
                if (attr->a_name != NULL) {
                        if (strcasecmp(attr->a_name, name) == 0)
                                return (attr);
                }
                attr = attr->a_next;
        }
        return (attr);
}

/*
 * Given a media list and a format number, this API will return the rtpmap
 * attribute matching the format number.
 */
sdp_attr_t *
sdp_find_media_rtpmap(sdp_media_t *media, const char *format)
{
        sdp_attr_t              *attr = NULL;
        char                    *tmp = NULL;

        if (media == NULL || format == NULL || (strlen(format) == 0)) {
                return (NULL);
        }
        attr = media->m_attr;
        while (attr != NULL) {
                if (attr->a_name != NULL && (strcasecmp(attr->a_name,
                    SDP_RTPMAP) == 0)) {
                        if (attr->a_value != NULL) {
                                tmp = attr->a_value;
                                while (isspace(*tmp))
                                        ++tmp;
                                if (strncasecmp(tmp, format,
                                    strlen(format)) == 0) {
                                        return (attr);
                                }
                        }
                }
                attr = attr->a_next;
        }
        return (attr);
}

/*
 * Adds origin field to the session.
 * o=<username> <sess-id> <sess-version> <nettype> <addrtype> <unicast-address>
 */
int
sdp_add_origin(sdp_session_t *session, const char *name, uint64_t id,
    uint64_t ver, const char *nettype, const char *addrtype,
    const char *address)
{
        sdp_origin_t            *origin;
        int                     ret = 0;

        if (session == NULL || name == NULL || nettype == NULL ||
            addrtype == NULL || address == NULL) {
                return (EINVAL);
        }
        if (session->s_origin != NULL)
                return (EPROTO);
        origin = calloc(1, sizeof (sdp_origin_t));
        if (origin == NULL)
                return (ENOMEM);
        origin->o_id = id;
        origin->o_version = ver;
        if ((ret = commp_add_str(&origin->o_username, name, strlen(name))) != 0)
                goto err_ret;
        if ((ret = commp_add_str(&origin->o_nettype, nettype,
            strlen(nettype))) != 0) {
                goto err_ret;
        }
        if ((ret = commp_add_str(&origin->o_addrtype, addrtype,
            strlen(addrtype))) != 0) {
                goto err_ret;
        }
        if ((ret = commp_add_str(&origin->o_address, address,
            strlen(address))) != 0) {
                goto err_ret;
        }
        session->s_origin = origin;
        return (ret);
err_ret:
        sdp_free_origin(origin);
        return (ret);
}

/*
 * Adds session name field to the session.
 * s=<session name>
 */
int
sdp_add_name(sdp_session_t *session, const char *name)
{
        if (session == NULL || name == NULL)
                return (EINVAL);
        if (session->s_name != NULL)
                return (EPROTO);
        return (commp_add_str(&session->s_name, name, strlen(name)));
}

/*
 * Adds session information field to the session or media section of SDP.
 * i=<session description>
 */
int
sdp_add_information(char **information, const char *value)
{
        if (information == NULL || value == NULL)
                return (EINVAL);
        if (*information != NULL)
                return (EPROTO);
        return (commp_add_str(information, value, strlen(value)));
}

/*
 * Adds uri field to the session.
 * u=<uri>
 */
int
sdp_add_uri(sdp_session_t *session, const char *uri)
{
        if (session == NULL || uri == NULL)
                return (EINVAL);
        if (session->s_uri != NULL)
                return (EPROTO);
        return (commp_add_str(&session->s_uri, uri, strlen(uri)));
}

/*
 * Adds email address field to the session.
 * e=<email-address>
 */
int
sdp_add_email(sdp_session_t *session, const char *email)
{
        if (session == NULL || email == NULL || (strlen(email) == 0))
                return (EINVAL);
        return (add_value_to_list(&session->s_email, email, strlen(email),
            B_TRUE));
}

/*
 * Adds phone number field to the session.
 * p=<phone-number>
 */
int
sdp_add_phone(sdp_session_t *session, const char *phone)
{
        if (session == NULL || phone == NULL || (strlen(phone) == 0))
                return (EINVAL);
        return (add_value_to_list(&session->s_phone, phone, strlen(phone),
            B_TRUE));
}

/*
 * Adds connection field to the session or media section of SDP
 * c=<nettype> <addrtype> <connection-address>[/ttl]/<number of addresses>
 */
int
sdp_add_connection(sdp_conn_t **conn, const char *nettype, const char *addrtype,
    const char *address, uint8_t ttl, int addrcount)
{
        sdp_conn_t              *tmp;
        sdp_conn_t              *new_conn;
        int                     ret = 0;

        if (conn == NULL || nettype == NULL || addrtype == NULL ||
            address == NULL) {
                return (EINVAL);
        }
        new_conn = calloc(1, sizeof (sdp_conn_t));
        if (new_conn == NULL)
                return (ENOMEM);
        new_conn->c_ttl = ttl;
        new_conn->c_addrcount = addrcount;
        if ((ret = commp_add_str(&new_conn->c_nettype, nettype,
            strlen(nettype))) != 0) {
                goto err_ret;
        }
        if ((ret = commp_add_str(&new_conn->c_addrtype, addrtype,
            strlen(addrtype))) != 0) {
                goto err_ret;
        }
        if ((ret = commp_add_str(&new_conn->c_address, address,
            strlen(address))) != 0) {
                goto err_ret;
        }
        if (*conn == NULL) {
                *conn = new_conn;
        } else {
                tmp = *conn;
                while (tmp->c_next != NULL)
                        tmp = tmp->c_next;
                tmp->c_next = new_conn;
        }
        return (ret);
err_ret:
        sdp_free_connection(new_conn);
        return (ret);
}

/*
 * Adds bandwidth field to the session or media section of SDP.
 * b=<bwtype>:<bandwidth>
 */
int
sdp_add_bandwidth(sdp_bandwidth_t **bw, const char *type, uint64_t value)
{
        sdp_bandwidth_t         *new_bw;
        sdp_bandwidth_t         *tmp;
        int                     ret = 0;

        if (bw == NULL || type == NULL)
                return (EINVAL);
        new_bw = calloc(1, sizeof (sdp_bandwidth_t));
        if (new_bw == NULL)
                return (ENOMEM);
        new_bw->b_value = value;
        if ((ret = commp_add_str(&new_bw->b_type, type, strlen(type))) != 0) {
                free(new_bw);
                return (ret);
        }
        if (*bw == NULL) {
                *bw = new_bw;
        } else {
                tmp = *bw;
                while (tmp->b_next != NULL)
                        tmp = tmp->b_next;
                tmp->b_next = new_bw;
        }
        return (ret);
}

/*
 * Adds time field to the session
 * t=<start-time> <stop-time>
 */
int
sdp_add_time(sdp_session_t *session, uint64_t starttime, uint64_t stoptime,
    sdp_time_t **time)
{
        sdp_time_t              *new_time;
        sdp_time_t              *tmp;

        if (time != NULL)
                *time = NULL;
        if (session == NULL) {
                return (EINVAL);
        }
        new_time = calloc(1, sizeof (sdp_time_t));
        if (new_time == NULL) {
                return (ENOMEM);
        }
        new_time->t_start = starttime;
        new_time->t_stop = stoptime;
        tmp = session->s_time;
        if (tmp == NULL)
                session->s_time = new_time;
        else {
                while (tmp->t_next != NULL)
                        tmp = tmp->t_next;
                tmp->t_next = new_time;
        }
        if (time != NULL)
                *time = new_time;
        return (0);
}

/*
 * Adds repeat field to the time structure of session
 * r=<repeat interval> <active duration> <offsets from start-time>
 */
int
sdp_add_repeat(sdp_time_t *time, uint64_t interval, uint64_t duration,
    const char *offset)
{
        sdp_repeat_t            *tmp;
        sdp_repeat_t            *new_repeat;
        int                     ret = 0;

        if (time == NULL || offset == NULL)
                return (EINVAL);
        new_repeat = calloc(1, sizeof (sdp_repeat_t));
        if (new_repeat == NULL)
                return (ENOMEM);
        new_repeat->r_interval = interval;
        new_repeat->r_duration = duration;
        if ((ret = sdp_str_to_list(&new_repeat->r_offset, offset,
            strlen(offset), B_FALSE)) != 0) {
                goto err_ret;
        }
        tmp = time->t_repeat;
        if (tmp == NULL) {
                time->t_repeat = new_repeat;
        } else {
                while (tmp->r_next != NULL)
                        tmp = tmp->r_next;
                tmp->r_next = new_repeat;
        }
        return (ret);
err_ret:
        sdp_free_repeat(new_repeat);
        return (ret);
}

/*
 * Adds time zone field to the session
 * z=<adjustment time> <offset> <adjustment time> <offset> ....
 */
int
sdp_add_zone(sdp_session_t *session, uint64_t time, const char *offset)
{
        sdp_zone_t              *new_zone;
        sdp_zone_t              *tmp;
        int                     ret = 0;

        if (session == NULL || offset == NULL)
                return (EINVAL);
        new_zone = calloc(1, sizeof (sdp_zone_t));
        if (new_zone == NULL)
                return (ENOMEM);
        new_zone->z_time = time;
        if ((ret = commp_add_str(&new_zone->z_offset, offset,
            strlen(offset))) != 0) {
                free(new_zone);
                return (ret);
        }
        tmp = session->s_zone;
        if (tmp == NULL) {
                session->s_zone = new_zone;
        } else {
                while (tmp->z_next != NULL) {
                        tmp = tmp->z_next;
                }
                tmp->z_next = new_zone;
        }
        return (ret);
}

/*
 * Adds key field to session or media section of SDP.
 * k=<method>
 * k=<method>:<encryption key>
 */
int
sdp_add_key(sdp_key_t **key, const char *method, const char *enckey)
{
        int                     ret = 0;

        if (key == NULL || method == NULL)
                return (EINVAL);
        if (*key != NULL)
                return (EPROTO);
        *key = calloc(1, sizeof (sdp_key_t));
        if (*key == NULL)
                return (ENOMEM);
        if ((ret = commp_add_str(&((*key)->k_method), method,
            strlen(method))) != 0) {
                goto err_ret;
        }
        if (enckey != NULL) {
                if ((ret = commp_add_str(&((*key)->k_enckey), enckey,
                    strlen(enckey))) != 0) {
                        goto err_ret;
                }
        }
        return (ret);
err_ret:
        sdp_free_key(*key);
        *key = NULL;
        return (ret);
}

/*
 * Adds attribute field to session or media section of SDP.
 * a=<attribute>
 * a=<attribute>:<value>
 */
int
sdp_add_attribute(sdp_attr_t **attr, const char *name, const char *value)
{
        sdp_attr_t              *tmp;
        sdp_attr_t              *new_attr;
        int                     ret = 0;

        if (attr == NULL || name == NULL)
                return (EINVAL);
        new_attr = calloc(1, sizeof (sdp_attr_t));
        if (new_attr == NULL)
                return (ENOMEM);
        if ((ret = commp_add_str(&new_attr->a_name, name, strlen(name))) != 0)
                goto err_ret;
        if (value != NULL) {
                if ((ret = commp_add_str(&new_attr->a_value, value,
                    strlen(value))) != 0) {
                        goto err_ret;
                }
        }
        tmp = *attr;
        if (tmp == NULL) {
                *attr = new_attr;
        } else {
                while (tmp->a_next != NULL)
                        tmp = tmp->a_next;
                tmp->a_next = new_attr;
        }
        return (ret);
err_ret:
        sdp_free_attribute(new_attr);
        return (ret);
}

/*
 * Adds media field to the session.
 * m=<media> <port>[/portcount] <proto> <fmt> ...
 */
int
sdp_add_media(sdp_session_t *session, const char *name, uint_t port,
    int portcount, const char *protocol, const char *fmt, sdp_media_t **media)
{
        sdp_media_t             *tmp;
        sdp_media_t             *new_media;
        int                     ret = 0;

        if (media != NULL)
                *media = NULL;
        if (session == NULL || name == NULL || protocol == NULL ||
            portcount <= 0 || fmt == NULL) {
                return (EINVAL);
        }
        new_media = calloc(1, sizeof (sdp_media_t));
        if (new_media == NULL) {
                return (ENOMEM);
        }
        new_media->m_session = session;
        new_media->m_port = port;
        new_media->m_portcount = portcount;
        if ((ret = commp_add_str(&new_media->m_name, name, strlen(name))) != 0)
                goto err_ret;
        if ((ret = commp_add_str(&new_media->m_proto, protocol,
            strlen(protocol))) != 0) {
                goto err_ret;
        }
        if ((ret = sdp_str_to_list(&new_media->m_format, fmt,
            strlen(fmt), B_TRUE)) != 0) {
                goto err_ret;
        }
        tmp = session->s_media;
        if (tmp == NULL) {
                session->s_media = new_media;
        } else {
                while (tmp->m_next != NULL)
                        tmp = tmp->m_next;
                tmp->m_next = new_media;
        }
        if (media != NULL)
                *media = new_media;
        return (0);
err_ret:
        sdp_free_media(new_media);
        return (ret);
}

/*
 * This internal API is required by sdp_session_to_str(). It determines the
 * length of buffer that is required to hold the session. Since the RFC does
 * not limit the size of various sub-fields in the field. We need to scan
 * through the structure to determine the length.
 */
int
sdp_get_length(const sdp_session_t *session)
{
        int                     len = 0;
        char                    buf[1];
        sdp_list_t              *list;
        sdp_conn_t              *conn;
        sdp_bandwidth_t         *bw;
        sdp_zone_t              *zone;
        sdp_time_t              *time;
        sdp_repeat_t            *repeat;
        sdp_attr_t              *attr;
        sdp_media_t             *media;

        len += FIELD_EQUALS_CRLF_LEN;
        len += snprintf(buf, 1, "%d", session->s_version);
        if (session->s_origin != NULL) {
                len += FIELD_EQUALS_CRLF_LEN;
                len += strlen(session->s_origin->o_username);
                len += snprintf(buf, 1, "%llu", session->s_origin->o_id) + 1;
                len += snprintf(buf, 1, "%llu", session->s_origin->o_version)
                    + 1;
                len += strlen(session->s_origin->o_nettype) + 1;
                len += strlen(session->s_origin->o_addrtype) + 1;
                len += strlen(session->s_origin->o_address) + 1;
        }
        if (session->s_name != NULL)
                len += strlen(session->s_name) + FIELD_EQUALS_CRLF_LEN;
        if (session->s_info != NULL)
                len += strlen(session->s_info) + FIELD_EQUALS_CRLF_LEN;
        if (session->s_uri != NULL)
                len += strlen(session->s_uri) + FIELD_EQUALS_CRLF_LEN;
        list = session->s_email;
        while (list != NULL) {
                len += strlen((char *)list->value) + FIELD_EQUALS_CRLF_LEN;
                list = list->next;
        }
        list = session->s_phone;
        while (list != NULL) {
                len += strlen((char *)list->value) + FIELD_EQUALS_CRLF_LEN;
                list = list->next;
        }
        conn = session->s_conn;
        SDP_LEN_CONNECTION(conn);
        bw = session->s_bw;
        SDP_LEN_BANDWIDTH(bw);
        time = session->s_time;
        while (time != NULL) {
                len += FIELD_EQUALS_CRLF_LEN;
                len += snprintf(buf, 1, "%llu", time->t_start);
                len += snprintf(buf, 1, "%llu", time->t_stop) + 1;
                repeat = time->t_repeat;
                while (repeat != NULL) {
                        len += FIELD_EQUALS_CRLF_LEN;
                        len += snprintf(buf, 1, "%llu", repeat->r_interval);
                        len += snprintf(buf, 1, "%llu", repeat->r_duration) + 1;
                        list = repeat->r_offset;
                        while (list != NULL) {
                                len += snprintf(buf, 1, "%llu",
                                    *(uint64_t *)list->value) + 1;
                                list = list->next;
                        }
                        repeat = repeat->r_next;
                }
                time = time->t_next;
        }
        if (session->s_zone != NULL)
                len += FIELD_EQUALS_CRLF_LEN;
        zone = session->s_zone;
        while (zone != NULL) {
                len += snprintf(buf, 1, "%llu", zone->z_time) + 1;
                len += strlen(zone->z_offset) + 1;
                zone = zone->z_next;
        }
        SDP_LEN_KEY(session->s_key);
        attr = session->s_attr;
        SDP_LEN_ATTRIBUTE(attr);
        media = session->s_media;
        while (media != NULL) {
                len += FIELD_EQUALS_CRLF_LEN;
                len += strlen(media->m_name);
                len += snprintf(buf, 1, "%u", media->m_port) + 1;
                len += snprintf(buf, 1, "%d", media->m_portcount) + 1;
                len += strlen(media->m_proto) + 1;
                list = media->m_format;
                while (list != NULL) {
                        len += strlen((char *)list->value) + 1;
                        list = list->next;
                }
                if (media->m_info != NULL)
                        len += strlen(media->m_info) + FIELD_EQUALS_CRLF_LEN;
                conn = media->m_conn;
                SDP_LEN_CONNECTION(conn);
                bw = media->m_bw;
                SDP_LEN_BANDWIDTH(bw);
                SDP_LEN_KEY(media->m_key);
                attr = media->m_attr;
                SDP_LEN_ATTRIBUTE(attr);
                media = media->m_next;
        }
        return (len);
}

/*
 * Given a session structure it clones (deep copy) and returns the cloned copy
 */
sdp_session_t *
sdp_clone_session(const sdp_session_t *session)
{
        sdp_session_t           *new_sess;
        sdp_origin_t            *origin;
        sdp_list_t              *list;
        sdp_time_t              *time;
        sdp_time_t              *new_time;
        sdp_repeat_t            *repeat;
        sdp_media_t             *media;
        sdp_media_t             *new_media;
        sdp_conn_t              *conn;
        sdp_bandwidth_t         *bw;
        sdp_attr_t              *attr;
        sdp_zone_t              *zone;
        char                    *offset = NULL;
        char                    *format = NULL;

        if (session == NULL)
                return (NULL);
        new_sess = calloc(1, sizeof (sdp_session_t));
        if (new_sess == NULL)
                return (NULL);
        new_sess->sdp_session_version = session->sdp_session_version;
        new_sess->s_version = session->s_version;
        origin = session->s_origin;
        if (origin != NULL && (sdp_add_origin(new_sess, origin->o_username,
            origin->o_id, origin->o_version, origin->o_nettype, origin->
            o_addrtype, origin->o_address) != 0)) {
                goto err_ret;
        }
        if (session->s_name != NULL && sdp_add_name(new_sess, session->
            s_name) != 0) {
                goto err_ret;
        }
        if (session->s_info != NULL && sdp_add_information(&new_sess->
            s_info, session->s_info) != 0) {
                goto err_ret;
        }
        if (session->s_uri != NULL && sdp_add_uri(new_sess, session->
            s_uri) != 0) {
                goto err_ret;
        }
        list = session->s_email;
        while (list != NULL) {
                if (sdp_add_email(new_sess, (char *)list->value) != 0)
                        goto err_ret;
                list = list->next;
        }
        list = session->s_phone;
        while (list != NULL) {
                if (sdp_add_phone(new_sess, (char *)list->value) != 0)
                        goto err_ret;
                list = list->next;
        }
        conn = session->s_conn;
        SDP_ADD_CONNECTION(new_sess->s_conn, conn);
        bw = session->s_bw;
        SDP_ADD_BANDWIDTH(new_sess->s_bw, bw);
        time = session->s_time;
        while (time != NULL) {
                if (sdp_add_time(new_sess, time->t_start, time->t_stop,
                    &new_time) != 0) {
                        goto err_ret;
                }
                repeat = time->t_repeat;
                while (repeat != NULL) {
                        if (sdp_list_to_str(repeat->r_offset, &offset,
                            B_FALSE) != 0) {
                                goto err_ret;
                        }
                        if (sdp_add_repeat(new_time, repeat->r_interval,
                            repeat->r_duration, offset) != 0) {
                                free(offset);
                                goto err_ret;
                        }
                        free(offset);
                        repeat = repeat->r_next;
                }
                time = time->t_next;
        }
        zone = session->s_zone;
        while (zone != NULL) {
                if (sdp_add_zone(new_sess, zone->z_time, zone->z_offset) != 0)
                        goto err_ret;
                zone = zone->z_next;
        }
        SDP_ADD_KEY(new_sess->s_key, session->s_key);
        attr = session->s_attr;
        SDP_ADD_ATTRIBUTE(new_sess->s_attr, attr);
        media = session->s_media;
        while (media != NULL) {
                if (sdp_list_to_str(media->m_format, &format, B_TRUE) != 0)
                        goto err_ret;
                if (sdp_add_media(new_sess, media->m_name,
                    media->m_port, media->m_portcount, media->m_proto,
                    format, &new_media) != 0) {
                        free(format);
                        goto err_ret;
                }
                free(format);
                if (media->m_info != NULL) {
                        if (sdp_add_information(&new_media->m_info,
                            media->m_info) != 0) {
                                goto err_ret;
                        }
                }
                conn = media->m_conn;
                SDP_ADD_CONNECTION(new_media->m_conn, conn);
                bw = media->m_bw;
                SDP_ADD_BANDWIDTH(new_media->m_bw, bw);
                SDP_ADD_KEY(new_media->m_key, media->m_key);
                attr = media->m_attr;
                SDP_ADD_ATTRIBUTE(new_media->m_attr, attr);
                new_media->m_session = new_sess;
                media = media->m_next;
        }
        return (new_sess);
err_ret:
        sdp_free_session(new_sess);
        return (NULL);
}

/*
 * should i check if individual members are NULL, if not snprintf
 * will core dump.
 */
/*
 * Given a session structure, this API converts it into character
 * buffer, which will be used as a payload later on.
 */
char *
sdp_session_to_str(const sdp_session_t *session, int *error)
{
        char                    *ret = NULL;
        char                    *buf = NULL;
        int                     len = 0;
        int                     s_len = 0;
        int                     wrote = 0;
        sdp_origin_t            *origin;
        sdp_list_t              *list;
        sdp_conn_t              *conn;
        sdp_attr_t              *attr;
        sdp_bandwidth_t         *bw;
        sdp_time_t              *time;
        sdp_repeat_t            *repeat;
        sdp_zone_t              *zone;
        sdp_media_t             *media;

        if (error != NULL)
                *error = 0;
        if (session == NULL) {
                if (error != NULL)
                        *error = EINVAL;
                return (NULL);
        }
        s_len = sdp_get_length(session);
        ret = malloc(s_len + 1);
        if (ret == NULL) {
                if (error != NULL)
                        *error = ENOMEM;
                return (NULL);
        }
        buf = ret;
        len = s_len + 1;
        wrote = snprintf(buf, len, "v=%d%s", session->s_version, COMMP_CRLF);
        len = len - wrote;
        buf = buf + wrote;
        origin = session->s_origin;
        if (origin != NULL) {
                wrote = snprintf(buf, len, "o=%s %llu %llu %s %s %s%s",
                    origin->o_username, origin->o_id, origin->o_version,
                    origin->o_nettype, origin->o_addrtype, origin->o_address,
                    COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
        }
        if (session->s_name != NULL) {
                wrote = snprintf(buf, len, "s=%s%s", session->s_name,
                    COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
        }
        SDP_INFORMATION_TO_STR(session->s_info);
        if (session->s_uri != NULL) {
                wrote = snprintf(buf, len, "u=%s%s", session->s_uri,
                    COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
        }
        list = session->s_email;
        while (list != NULL) {
                wrote = snprintf(buf, len, "e=%s%s", (char *)list->value,
                    COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
                list = list->next;
        }
        list = session->s_phone;
        while (list != NULL) {
                wrote = snprintf(buf, len, "p=%s%s", (char *)list->value,
                    COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
                list = list->next;
        }
        conn = session->s_conn;
        SDP_CONNECTION_TO_STR(conn);
        bw = session->s_bw;
        SDP_BANDWIDTH_TO_STR(bw);
        time = session->s_time;
        while (time != NULL) {
                wrote = snprintf(buf, len, "t=%llu %llu%s", time->t_start,
                    time->t_stop, COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
                repeat = time->t_repeat;
                while (repeat != NULL) {
                        wrote = snprintf(buf, len, "r=%llu %llu", repeat->
                            r_interval, repeat->r_duration);
                        len = len - wrote;
                        buf = buf + wrote;
                        list = repeat->r_offset;
                        while (list != NULL) {
                                wrote = snprintf(buf, len, " %llu",
                                    *(uint64_t *)list->value);
                                len = len - wrote;
                                buf = buf + wrote;
                                list = list->next;
                        }
                        wrote = snprintf(buf, len, "%s", COMMP_CRLF);
                        len = len - wrote;
                        buf = buf + wrote;
                        repeat = repeat->r_next;
                }
                time = time->t_next;
        }
        zone = session->s_zone;
        if (zone != NULL) {
                wrote = snprintf(buf, len, "z=%llu %s", zone->z_time,
                    zone->z_offset);
                len = len - wrote;
                buf = buf + wrote;
                zone = zone->z_next;
                while (zone != NULL) {
                        wrote = snprintf(buf, len, " %llu %s", zone->z_time,
                            zone->z_offset);
                        len = len - wrote;
                        buf = buf + wrote;
                        zone = zone->z_next;
                }
                wrote = snprintf(buf, len, "%s", COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
        }
        SDP_KEY_TO_STR(session->s_key);
        attr = session->s_attr;
        SDP_ATTR_TO_STR(attr);
        media = session->s_media;
        while (media != NULL) {
                if (media->m_portcount == 1) {
                        wrote = snprintf(buf, len, "m=%s %d %s", media->m_name,
                            media->m_port, media->m_proto);
                } else {
                        wrote = snprintf(buf, len, "m=%s %d/%d %s", media->
                            m_name, media->m_port, media->m_portcount, media->
                            m_proto);
                }
                len = len - wrote;
                buf = buf + wrote;
                list = media->m_format;
                while (list != NULL) {
                        wrote = snprintf(buf, len, " %s", (char *)list->value);
                        len = len - wrote;
                        buf = buf + wrote;
                        list = list->next;
                }
                wrote = snprintf(buf, len, "%s", COMMP_CRLF);
                len = len - wrote;
                buf = buf + wrote;
                SDP_INFORMATION_TO_STR(media->m_info);
                conn = media->m_conn;
                SDP_CONNECTION_TO_STR(conn);
                bw = media->m_bw;
                SDP_BANDWIDTH_TO_STR(bw);
                SDP_KEY_TO_STR(media->m_key);
                attr = media->m_attr;
                SDP_ATTR_TO_STR(attr);
                media = media->m_next;
        }
        assert(len >= 1);
        *buf = '\0';
        return (ret);
}

/*
 * Given a session structure and the field ('v', 'o', 's', et al), this API
 * deletes the corresponding structure element. It frees the memory and sets the
 * pointer to NULL
 */
int
sdp_delete_all_field(sdp_session_t *session, const char field)
{
        if (session == NULL)
                return (EINVAL);
        switch (field) {
                case SDP_ORIGIN_FIELD:
                        sdp_free_origin(session->s_origin);
                        session->s_origin = NULL;
                        break;
                case SDP_NAME_FIELD:
                        free(session->s_name);
                        session->s_name = NULL;
                        break;
                case SDP_INFO_FIELD:
                        free(session->s_info);
                        session->s_info = NULL;
                        break;
                case SDP_URI_FIELD:
                        free(session->s_uri);
                        session->s_uri = NULL;
                        break;
                case SDP_EMAIL_FIELD:
                        sdp_free_list(session->s_email);
                        session->s_email = NULL;
                        break;
                case SDP_PHONE_FIELD:
                        sdp_free_list(session->s_phone);
                        session->s_phone = NULL;
                        break;
                case SDP_CONNECTION_FIELD:
                        sdp_free_connection(session->s_conn);
                        session->s_conn = NULL;
                        break;
                case SDP_BANDWIDTH_FIELD:
                        sdp_free_bandwidth(session->s_bw);
                        session->s_bw = NULL;
                        break;
                case SDP_TIME_FIELD:
                        sdp_free_time(session->s_time);
                        session->s_time = NULL;
                        break;
                case SDP_ZONE_FIELD:
                        sdp_free_zone(session->s_zone);
                        session->s_zone = NULL;
                        break;
                case SDP_KEY_FIELD:
                        sdp_free_key(session->s_key);
                        session->s_key = NULL;
                        break;
                case SDP_ATTRIBUTE_FIELD:
                        sdp_free_attribute(session->s_attr);
                        session->s_attr = NULL;
                        break;
                case SDP_MEDIA_FIELD:
                        sdp_free_media(session->s_media);
                        session->s_media = NULL;
                        break;
                default:
                        return (EINVAL);
        }
        return (0);
}

/*
 * Given a media structure and the field ('i', 'b', 'c', et al), this API
 * deletes the corresponding structure element. It frees the memory and sets
 * the pointer to NULL.
 */
int
sdp_delete_all_media_field(sdp_media_t *media, const char field)
{
        if (media == NULL)
                return (EINVAL);
        switch (field) {
                case SDP_INFO_FIELD:
                        free(media->m_info);
                        media->m_info = NULL;
                        break;
                case SDP_CONNECTION_FIELD:
                        sdp_free_connection(media->m_conn);
                        media->m_conn = NULL;
                        break;
                case SDP_BANDWIDTH_FIELD:
                        sdp_free_bandwidth(media->m_bw);
                        media->m_bw = NULL;
                        break;
                case SDP_KEY_FIELD:
                        sdp_free_key(media->m_key);
                        media->m_key = NULL;
                        break;
                case SDP_ATTRIBUTE_FIELD:
                        sdp_free_attribute(media->m_attr);
                        media->m_attr = NULL;
                        break;
                default:
                        return (EINVAL);
        }
        return (0);
}

/*
 * Given a media list and the media, this API deletes that media from the
 * list. It frees the memory corresponding to that media.
 */
int
sdp_delete_media(sdp_media_t **l_media, sdp_media_t *media)
{
        sdp_media_t             *cur;
        sdp_media_t             *prev;

        if (l_media == NULL || *l_media == NULL || media == NULL)
                return (EINVAL);
        cur = *l_media;
        prev = NULL;
        while (cur != NULL && cur != media) {
                prev = cur;
                cur = cur->m_next;
        }
        if (cur == NULL)
                return (EINVAL);
        if (cur == *l_media)
                *l_media = cur->m_next;
        else
                prev->m_next = cur->m_next;
        cur->m_next = NULL;
        sdp_free_media(cur);
        return (0);
}

/*
 * Given an attribute list and an attribute, this API deletes that attribue
 * from the list. It frees the memory corresponding to that attribute.
 */
int
sdp_delete_attribute(sdp_attr_t **l_attr, sdp_attr_t *attr)
{
        sdp_attr_t              *cur;
        sdp_attr_t              *prev;

        if (l_attr == NULL || *l_attr == NULL || attr == NULL)
                return (EINVAL);
        cur = *l_attr;
        prev = NULL;
        while (cur != NULL && cur != attr) {
                prev = cur;
                cur = cur->a_next;
        }
        if (cur == NULL)
                return (EINVAL);
        if (cur == *l_attr)
                *l_attr = cur->a_next;
        else
                prev->a_next = cur->a_next;
        cur->a_next = NULL;
        sdp_free_attribute(cur);
        return (0);
}

/*
 * Allocates a new sdp session structure and assigns a version number to it.
 * Currently one version is defined and it is 1. This will be useful in future
 * in the unlikely need to change the structure.
 */
sdp_session_t *
sdp_new_session()
{
        sdp_session_t   *session = NULL;

        session = calloc(1, sizeof (sdp_session_t));
        if (session != NULL)
                session->sdp_session_version = SDP_SESSION_VERSION_1;
        return (session);
}