bta/hf_client/bta_hf_client_at.c

/******************************************************************************
 *
 *  Copyright (C) 2004-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  BTA AG AT command interpreter.
 *
 ******************************************************************************/

#include <string.h>
#include "gki.h"
#include "bta_ag_at.h"
#include "utl.h"

/*****************************************************************************
**  Constants
*****************************************************************************/

/******************************************************************************
**
** Function         bta_ag_at_init
**
** Description      Initialize the AT command parser control block.
**
**
** Returns          void
**
******************************************************************************/
void bta_ag_at_init(tBTA_AG_AT_CB *p_cb)
{
    p_cb->p_cmd_buf = NULL;
    p_cb->cmd_pos = 0;
}

/******************************************************************************
**
** Function         bta_ag_at_reinit
**
** Description      Re-initialize the AT command parser control block.  This
**                  function resets the AT command parser state and frees
**                  any GKI buffer.
**
**
** Returns          void
**
******************************************************************************/
void bta_ag_at_reinit(tBTA_AG_AT_CB *p_cb)
{
    if (p_cb->p_cmd_buf != NULL)
    {
        GKI_freebuf(p_cb->p_cmd_buf);
        p_cb->p_cmd_buf = NULL;
    }
    p_cb->cmd_pos = 0;
}
/******************************************************************************
**
** Function         bta_ag_process_at
**
** Description      Parse AT commands.  This function will take the input
**                  character string and parse it for AT commands according to
**                  the AT command table passed in the control block.
**
**
** Returns          void
**
******************************************************************************/
void bta_ag_process_at(tBTA_AG_AT_CB *p_cb)
{
    UINT16      idx;
    UINT8       arg_type;
    char        *p_arg;
    INT16       int_arg = 0;
    /* loop through at command table looking for match */
    for (idx = 0; p_cb->p_at_tbl[idx].p_cmd[0] != 0; idx++)
    {
        if (!utl_strucmp(p_cb->p_at_tbl[idx].p_cmd, p_cb->p_cmd_buf))
        {
            break;
        }
    }

    /* if there is a match; verify argument type */
    if (p_cb->p_at_tbl[idx].p_cmd[0] != 0)
    {
        /* start of argument is p + strlen matching command */
        p_arg = p_cb->p_cmd_buf + strlen(p_cb->p_at_tbl[idx].p_cmd);

        /* if no argument */
        if (p_arg[0] == 0)
        {
            arg_type = BTA_AG_AT_NONE;
        }
        /* else if arg is '?' and it is last character */
        else if (p_arg[0] == '?' && p_arg[1] == 0)
        {
            /* we have a read */
            arg_type = BTA_AG_AT_READ;
        }
        /* else if arg is '=' */
        else if (p_arg[0] == '=' && p_arg[1] != 0)
        {
            if (p_arg[1] == '?' && p_arg[2] == 0)
            {
                /* we have a test */
                arg_type = BTA_AG_AT_TEST;
            }
            else
            {
                /* we have a set */
                arg_type = BTA_AG_AT_SET;

                /* skip past '=' */
                p_arg++;
            }
        }
        else
        /* else it is freeform argument */
        {
            arg_type = BTA_AG_AT_FREE;
        }

        /* if arguments match command capabilities */
        if ((arg_type & p_cb->p_at_tbl[idx].arg_type) != 0)
        {
            /* if it's a set integer check max, min range */
            if (arg_type == BTA_AG_AT_SET &&
                p_cb->p_at_tbl[idx].fmt == BTA_AG_AT_INT)
            {
                int_arg = utl_str2int(p_arg);
                if (int_arg < (INT16) p_cb->p_at_tbl[idx].min ||
                    int_arg > (INT16) p_cb->p_at_tbl[idx].max)
                {
                    /* arg out of range; error */
                    (*p_cb->p_err_cback)(p_cb->p_user, FALSE, NULL);
                }
                else
                {

                    (*p_cb->p_cmd_cback)(p_cb->p_user, idx, arg_type, p_arg, int_arg);
                }
            }
            else
            {
                (*p_cb->p_cmd_cback)(p_cb->p_user, idx, arg_type, p_arg, int_arg);
            }
        }
        /* else error */
        else
        {
            (*p_cb->p_err_cback)(p_cb->p_user, FALSE, NULL);
        }
    }
    /* else no match call error callback */
    else
    {
        (*p_cb->p_err_cback)(p_cb->p_user, TRUE, p_cb->p_cmd_buf);
    }
}

/******************************************************************************
**
** Function         bta_ag_at_parse
**
** Description      Parse AT commands.  This function will take the input
**                  character string and parse it for AT commands according to
**                  the AT command table passed in the control block.
**
**
** Returns          void
**
******************************************************************************/
void bta_ag_at_parse(tBTA_AG_AT_CB *p_cb, char *p_buf, UINT16 len)
{
    int i = 0;
    char* p_save;

    if (p_cb->p_cmd_buf == NULL)
    {
        p_cb->p_cmd_buf = (char *) GKI_getbuf(p_cb->cmd_max_len);
        p_cb->cmd_pos = 0;
    }

    for (i = 0; i < len;)
    {
        while (p_cb->cmd_pos < p_cb->cmd_max_len-1 && i < len)
        {
            /* Skip null characters between AT commands. */
            if ((p_cb->cmd_pos == 0) && (p_buf[i] == 0))
            {
                i++;
                continue;
            }

            p_cb->p_cmd_buf[p_cb->cmd_pos] = p_buf[i++];
            if ( p_cb->p_cmd_buf[p_cb->cmd_pos] == '\r' || p_cb->p_cmd_buf[p_cb->cmd_pos] == '\n')
            {
                p_cb->p_cmd_buf[p_cb->cmd_pos] = 0;
                if ((p_cb->cmd_pos > 2)                                      &&
                    (p_cb->p_cmd_buf[0] == 'A' || p_cb->p_cmd_buf[0] == 'a') &&
                    (p_cb->p_cmd_buf[1] == 'T' || p_cb->p_cmd_buf[1] == 't'))
                {
                    p_save = p_cb->p_cmd_buf;
                    p_cb->p_cmd_buf += 2;
                    bta_ag_process_at(p_cb);
                    p_cb->p_cmd_buf = p_save;
                }

                p_cb->cmd_pos = 0;

            }
            else if( p_cb->p_cmd_buf[p_cb->cmd_pos] == 0x1A || p_cb->p_cmd_buf[p_cb->cmd_pos] == 0x1B )
            {
                p_cb->p_cmd_buf[++p_cb->cmd_pos] = 0;
                (*p_cb->p_err_cback)(p_cb->p_user, TRUE, p_cb->p_cmd_buf);
                p_cb->cmd_pos = 0;
            }
            else
            {
                ++p_cb->cmd_pos;
            }
        }

        if (i < len)
            p_cb->cmd_pos = 0;
    }
}