Zabbix

/*

** Copyright (C) 2001-2025 Zabbix SIA

**

** This program is free software: you can redistribute it and/or modify it under the terms of

** the GNU Affero General Public License as published by the Free Software Foundation, version 3.

**

** 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 Affero General Public License for more details.

**

** You should have received a copy of the GNU Affero General Public License along with this program.

** If not, see <https://www.gnu.org/licenses/>.

**/

​

#include "zbxmedia.h"

​

#include "zbxstr.h"

​

#include <termios.h>

​

#define ZBX_AT_ESC  "\x1B"

#define ZBX_AT_CTRL_Z   "\x1A"

​

static int  write_gsm(int fd, const char *str, char *error, int max_error_len)

{

    int i, wlen, len, ret = SUCCEED;

​

    zabbix_log(LOG_LEVEL_DEBUG, "In %s() str:'%s'", __func__, str);

​

    len = strlen(str);

​

    for (wlen = 0; wlen < len; wlen += i)

    {

        if (-1 == (i = write(fd, str + wlen, len - wlen)))

        {

            i = 0;

​

            if (EAGAIN == errno)

                continue;

​

            zabbix_log(LOG_LEVEL_DEBUG, "error writing to GSM modem: %s", zbx_strerror(errno));

            if (NULL != error)

                zbx_snprintf(error, max_error_len, "error writing to GSM modem: %s", zbx_strerror(errno));

​

            ret = FAIL;

            break;

        }

    }

​

    zabbix_log(LOG_LEVEL_DEBUG, "End of %s():%s", __func__, zbx_result_string(ret));

​

    return ret;

}

​

static int  check_modem_result(char *buffer, char **ebuf, char **sbuf, const char *expect, char *error,

        int max_error_len)

{

    char    rcv[0xff];

    int i, len, ret = SUCCEED;

​

    zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __func__);

​

    zbx_strlcpy(rcv, *sbuf, sizeof(rcv));

​

    do

    {

        len = *ebuf - *sbuf;

        for (i = 0; i < len && (*sbuf)[i] != '\n' && (*sbuf)[i] != '\r'; i++)

            ; /* find first '\r' & '\n' */

​

        if (i < len)

            (*sbuf)[i++] = '\0';

​

        ret = (NULL == strstr(*sbuf, expect)) ? FAIL : SUCCEED;

​

        *sbuf += i;

​

        if (*sbuf != buffer)

        {

            memmove(buffer, *sbuf, *ebuf - *sbuf + 1); /* +1 for '\0' */

            *ebuf -= *sbuf - buffer;

            *sbuf = buffer;

        }

    }

    while (*sbuf < *ebuf && FAIL == ret);

​

    if (FAIL == ret && NULL != error)

    {

        zbx_snprintf(error, (size_t)max_error_len, "modem communication error");

        zabbix_log(LOG_LEVEL_WARNING, "modem communication error: expected [%s] received [%s]",

                expect, rcv);