BeRTOS
test2.c
00001 /*
00002 Copyright (c) 2005, David M Howard (daveh at dmh2000.com)
00003 All rights reserved.
00004 
00005 This product is licensed for use and distribution under the BSD Open Source License.
00006 see the file COPYING for more details.
00007 
00008 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
00009 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
00010 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
00011 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
00012 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 
00013 OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
00014 OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 
00015 OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
00016 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 
00017 OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
00018 EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
00019 
00020 */
00021 
00022 /*
00023 ========================================================================================================
00024 EXAMPLE : SETUP FOR GGA AND RMC SENTENCES WITH CHARACTER BY CHARACTER IO
00025 =======================================================================================================
00026 */   
00027 
00028 
00029 #include <stdio.h>
00030 #include <stdlib.h>
00031 #include <string.h>
00032 #include "nmeap.h"
00033 
00034 nmeap_gga_t g_gga;
00035 
00036 char test_vector[] = {
00037 "$GPGGA,123519,3929.946667,N,11946.086667,E,1,08,0.9,545.4,M,46.9,M,,*4A\r\n" /* good */
00038 "$xyz,1234,asdfadfasdfasdfljsadfkjasdfk\r\n"                                  /* junk */
00039 "$GPRMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*68\r\n"      /* good */
00040 "$GPRMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*48\r\n"      /* checksum error */
00041 };
00042 
00043 char *pvec = test_vector;
00044 
00046 int readbuffer(char *buffer,int len)
00047 {
00048     int i;
00049     
00050     if (*pvec == 0) {
00051         // end of file
00052         return -1;
00053     }
00054     
00055     for(i=0;i<len;i++) {
00056         /* quit when no more data */
00057         if (*pvec == 0) {
00058             break;
00059         }
00060         buffer[i] = *pvec++;
00061     }
00062     return i;
00063 }
00064 
00066 static void print_gga(nmeap_gga_t *gga)
00067 {
00068     printf("found GPGGA message %.6f %.6f %.0f %lu %d %d %f %f\n",
00069             gga->latitude  ,
00070             gga->longitude, 
00071             gga->altitude , 
00072             gga->time     , 
00073             gga->satellites,
00074             gga->quality   ,
00075             gga->hdop      ,
00076             gga->geoid     
00077             );
00078 }
00079 
00081 static void gpgga_callout(nmeap_context_t *context,void *data,void *user_data)
00082 {
00083     nmeap_gga_t *gga = (nmeap_gga_t *)data;
00084     
00085     printf("-------------callout\n");
00086     print_gga(gga);
00087 }
00088 
00089 
00091 static void print_rmc(nmeap_rmc_t *rmc)
00092 {
00093     printf("found GPRMC Message %lu %c %.6f %.6f %f %f %lu %f\n",
00094             rmc->time,
00095             rmc->warn,
00096             rmc->latitude,
00097             rmc->longitude,
00098             rmc->speed,
00099             rmc->course,
00100             rmc->date,
00101             rmc->magvar
00102             );
00103 }
00104 
00106 static void gprmc_callout(nmeap_context_t *context,void *data,void *user_data)
00107 {
00108     nmeap_rmc_t *rmc = (nmeap_rmc_t *)data;
00109     
00110     printf("-------------callout\n");
00111     print_rmc(rmc);
00112 }
00113 
00114 /* ---------------------------------------------------------------------------------------*/
00115 /* STEP 1 : allocate the data structures. be careful if you put them on the stack because */
00116 /*          they need to be live for the duration of the parser                           */
00117 /* ---------------------------------------------------------------------------------------*/
00118 static nmeap_context_t nmea;       /* parser context */
00119 static nmeap_gga_t     gga;        /* this is where the data from GGA messages will show up */
00120 static nmeap_rmc_t     rmc;        /* this is where the data from RMC messages will show up */
00121 static int             user_data; /* user can pass in anything. typically it will be a pointer to some user data */
00122 
00123 int main(int argc,char *argv[])
00124 {
00125     int  status;
00126     int  rem;
00127     int  offset;
00128     int  len;
00129     char buffer[32];
00130     
00131     /* ---------------------------------------*/
00132     /*STEP 2 : initialize the nmea context    */                                                
00133     /* ---------------------------------------*/
00134     status = nmeap_init(&nmea,(void *)&user_data);
00135     if (status != 0) {
00136         printf("nmeap_init %d\n",status);
00137         exit(1);
00138     }
00139     
00140     /* ---------------------------------------*/
00141     /*STEP 3 : add standard GPGGA parser      */                                                
00142     /* -------------------------------------- */
00143     status = nmeap_addParser(&nmea,"GPGGA",nmeap_gpgga,gpgga_callout,&gga);
00144     if (status != 0) {
00145         printf("nmeap_add %d\n",status);
00146         exit(1);
00147     }
00148 
00149     /* ---------------------------------------*/
00150     /*STEP 4 : add standard GPRMC parser      */                                                
00151     /* -------------------------------------- */
00152     status = nmeap_addParser(&nmea,"GPRMC",nmeap_gprmc,gprmc_callout,&rmc);
00153     if (status != 0) {
00154         printf("nmeap_add %d\n",status);
00155         exit(1);
00156     }
00157     
00158     /* ---------------------------------------*/
00159     /*STEP 5 : process input until done       */                                                
00160     /* -------------------------------------- */
00161     for(;;) {
00162         /* ---------------------------------------*/
00163         /*STEP 6 : get a buffer of input          */                                                
00164         /* -------------------------------------- */
00165         len = rem = readbuffer(buffer,sizeof(buffer));
00166         if (len <= 0) {
00167             break;
00168         }
00169         
00170         /* ----------------------------------------------*/
00171         /*STEP 7 : process input until buffer is used up */                                                
00172         /* --------------------------------------------- */
00173         offset = 0;
00174         while(rem > 0) {
00175             /* --------------------------------------- */
00176             /*STEP 8 : pass it to the parser           */
00177             /* status indicates whether a complete msg */
00178             /* arrived for this byte                   */
00179             /* NOTE : in addition to the return status */
00180             /* the message callout will be fired when  */
00181             /* a complete message is processed         */
00182             /* --------------------------------------- */
00183             status = nmeap_parseBuffer(&nmea,&buffer[offset],&rem);
00184             offset += (len - rem); 
00185             
00186             /* ---------------------------------------*/
00187             /*STEP 9 : process the return code        */                                                
00188             /* -------------------------------------- */
00189             switch(status) {
00190             case NMEAP_GPGGA:
00191                 printf("-------------switch\n");
00192                 print_gga(&gga);
00193                 printf("-------------\n");
00194                 break;
00195             case NMEAP_GPRMC:
00196                 printf("-------------switch\n");
00197                 print_rmc(&rmc);
00198                 printf("-------------\n");
00199                 break;
00200             default:
00201                 break;
00202             }
00203         }
00204     }
00205     
00206     return 0;
00207 }
00208