File content as of revision 4:63a2619b423b:

/*
  gprs.cpp
  2013 Copyright (c) Seeed Technology Inc.  All right reserved.

  Author:lawliet.zou@gmail.com
  2013-11-14

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/
#include "gprs.h"

int GPRS::readBuffer(char *buffer,int count)
{
    int i = 0;
    timeCnt.start();  // start timer
    while(1) {
        while (gprsSerial.readable()) {
            char c = gprsSerial.getc();
            if (c == '\r' || c == '\n') c = '$';
            buffer[i++] = c;
            if(i > count)break;
        }
        if(i > count)break;
        if(timeCnt.read() > DEFAULT_TIMEOUT) {
            timeCnt.stop();
            timeCnt.reset();
            break;
        }
    }
    wait(0.5);
    while(gprsSerial.readable()) {	// display the other thing..
        char c = gprsSerial.getc();
    }
    return 0;
}

void cleanBuffer(char *buffer, int count)
{
    for(int i=0; i < count; i++) {
        buffer[i] = '\0';
    }
}

void GPRS::sendCmd(char *cmd)
{
    gprsSerial.puts(cmd);
}

int GPRS::waitForResp(char *resp, int timeout)
{
    int len = strlen(resp);
    int sum=0;
    timeCnt.start();

    while(1) {
        if(gprsSerial.readable()) {
            char c = gprsSerial.getc();
            sum = (c==resp[sum]) ? sum+1 : 0;
            if(sum == len)break;
        }
        if(timeCnt.read() > timeout) {	// time out
            timeCnt.stop();
            timeCnt.reset();
            return -1;
        }
    }
    timeCnt.stop();                	// stop timer
    timeCnt.reset();             		// clear timer
    while(gprsSerial.readable()) {  	// display the other thing..
        char c = gprsSerial.getc();
    }

    return 0;
}

int GPRS::sendCmdAndWaitForResp(char *cmd, char *resp, int timeout)
{
    sendCmd(cmd);
    return waitForResp(resp,timeout);
}

int GPRS::init(void)
{
    if(0 != checkSIMStatus()) {
        return -1;
    }
    if(checkSignalStrength()<1) {
        return -1;
    }
    if(0 != settingSMS()) {
        return -1;
    }
    return 0;
}

int GPRS::checkSIMStatus(void)
{
    char gprsBuffer[30];
    int count = 0;
    cleanBuffer(gprsBuffer,30);
    while(count < 3) {
        sendCmd("AT+CPIN?\r\n");
        readBuffer(gprsBuffer,30);
        if((NULL != strstr(gprsBuffer,"+CPIN: READY"))) {
            break;
        }
        count++;
        wait(1);
    }

    if(count == 3) {
        return -1;
    }
    return 0;
}

int GPRS::checkSignalStrength(void)
{
    char gprsBuffer[100];
    int index,count = 0;
    cleanBuffer(gprsBuffer,100);
    while(count < 3) {
        sendCmd("AT+CSQ\r\n");
        readBuffer(gprsBuffer,25);
        if(sscanf(gprsBuffer, "AT+CSQ$$$$+CSQ: %d", &index)>0) {
            break;
        }
        count++;
        wait(1);
    }
    if(count == 3) {
        return -1;
    }
    return index;
}

int GPRS::settingSMS(void)
{
    if(0 != sendCmdAndWaitForResp("AT+CNMI=2,2\r\n", "OK", DEFAULT_TIMEOUT)) {
        return -1;
    }
    if(0 != sendCmdAndWaitForResp("AT+CMGF=1\r\n", "OK", DEFAULT_TIMEOUT)) {
        return -1;
    }
    return 0;
}

int GPRS::sendSMS(char *number, char *data)
{
    char cmd[64];
    while(gprsSerial.readable()) {
        char c = gprsSerial.getc();
    }
    snprintf(cmd, sizeof(cmd),"AT+CMGS=\"%s\"\r\n",number);
    if(0 != sendCmdAndWaitForResp(cmd,">",DEFAULT_TIMEOUT)) {
        return -1;
    }
    wait(1);
    gprsSerial.puts(data);
    gprsSerial.putc((char)0x1a);
    return 0;
}

int GPRS::readSMS(char *message, int index)
{
    int i = 0;
    char gprsBuffer[100];
    char *p,*s;
    gprsSerial.printf("AT+CMGR=%d\r\n",index);
    cleanBuffer(gprsBuffer,100);
    readBuffer(gprsBuffer,100);
    if(NULL == ( s = strstr(gprsBuffer,"+CMGR"))) {
        return -1;
    }
    if(NULL != ( s = strstr(gprsBuffer,"+32"))) {
        p = s + 6;
        while((*p != '$')&&(i < SMS_MAX_LENGTH-1)) {
            message[i++] = *(p++);
        }
        message[i] = '\0';
    }
    return 0;
}

int GPRS::deleteSMS(int index)
{
    char cmd[32];
    snprintf(cmd,sizeof(cmd),"AT+CMGD=%d\r\n",index);
    sendCmd(cmd);
    return 0;
}

int GPRS::getSMS(char* message)
{
    if(NULL != messageBuffer) {
        strncpy(message,messageBuffer,SMS_MAX_LENGTH);
    }
    return 0;
}

int GPRS::callUp(char *number)
{
    if(0 != sendCmdAndWaitForResp("AT+COLP=1\r\n","OK",5)) {
        return -1;
    }
    wait(1);
    gprsSerial.printf("\r\nATD%s;\r\n",NULL==number?phoneNumber:number);
    return 0;
}

int GPRS::answer(void)
{
    gprsSerial.printf("ATA\r\n");
    return 0;
}

int GPRS::loopHandle(void)
{
    char gprsBuffer[100];
    int i = 0;
    char *s = NULL;
    cleanBuffer(gprsBuffer,100);
    while(gprsSerial.readable()) {
        char c = gprsSerial.getc();
    }
    wait(1);
START:
    while(1) {
        if(gprsSerial.readable()) {
            break;
        }
        wait(1);
    }
    timeCnt.start();  // start timer
    while(1) {
        while (gprsSerial.readable()) {
            char c = gprsSerial.getc();
            if (c == '\r' || c == '\n') c = '$';
            gprsBuffer[i] = c;
            i++;
            if(i > 100) {
                i = 0;
                break;
            }
        }
        if(timeCnt.read() > 5) {          // time out
            timeCnt.stop();
            timeCnt.reset();
            break;
        }
    }
    if(NULL != strstr(gprsBuffer,"RING")) {
        return MESSAGE_RING;
    } else if(NULL != (s = strstr(gprsBuffer,"+CMT"))) { //SMS: $$+CMTI: "SM",24$$
        if(NULL != (s = strstr(gprsBuffer,"+32"))) {
            s += 6;
            int i = 0;
            cleanBuffer(messageBuffer,SMS_MAX_LENGTH);
            while((*s != '$')&&(i < SMS_MAX_LENGTH-1)) {
                messageBuffer[i++] = *(s++);
            }
            messageBuffer[i] = '\0';
            return MESSAGE_SMS;
        } else {
            goto START;
        }
    } else {
        goto START;
    }
}


int GPRS::connectTCP(char *ip, char *port)
{
    char cipstart[50];
    if(0 != sendCmdAndWaitForResp("AT+CSTT=\"CMNET\",\"\",\"\"\r\n", "OK", 5)) {
        return -1;
    }
    sprintf(cipstart, "AT+CIPSTART=\"TCP\",\"%s\",\"%s\"\r\n", ip, port);
    if(0 != sendCmdAndWaitForResp(cipstart, "OK", 5)) {
        return -1;
    }
    return 0;
}
int GPRS::sendTCPData(char *data)
{
    char cmd[64];
    int len = strlen(data);
    snprintf(cmd,sizeof(cmd),"AT+CIPSEND=%d\r\n",len);
    if(0 != sendCmdAndWaitForResp(cmd,">",DEFAULT_TIMEOUT)) {
        return -1;
    }
    if(0 != sendCmdAndWaitForResp(data,"OK",DEFAULT_TIMEOUT)) {
        return -1;
    }
    return 0;
}

int GPRS::closeTCP(void)
{
    sendCmd("AT+CIPCLOSE\r\n");
    return 0;
}

int GPRS::shutTCP(void)
{
    sendCmd("AT+CIPSHUT\r\n");
    return 0;
}