OS/2 Shareware BBS: 10 Tools/10-Tools.zip/csso0301.zip/SAMPLES/C-API/SOURCE/EMBEDD.CPP

C/C++ Source or Header | 2000-02-18 | 5.5 KB | 190 lines

/*  Copyright (c) 1998-2000 IBK-Landquart-Switzerland. All rights reserved.
 *
 *  Module      :  Embedd.cpp
 *  Application :  Sample to embedd CSS as macro language with C-API
 *  Author      :  Peter Koch, IBK
 *
 *  NOTES:
 *
 *  (1) Within C/C++ implementions of CSS functions there is no need to
 *      handle errors since that will be done by the caller. Just return
 *      in case of an error.
 *
 *  (2) These functions will allways return a value of 0, so there is no
 *      need to check for errors.
 *
 *  (3) In real applications you could first call KCssGet to get the
 *      required size and then allocate the buffer dynamicly (like in
 *      checkErrs).

 *  Date        Description                                 Who
 *  --------------------------------------------------------------------------
 *  Feb 2000    First release                               P.Koch, IBK
 */
#include <stdlib.h>
#include <stdio.h>
#include <iostream.h>
#include <KCssC.h>

static char* module = "Embedd.exe";      // module name
static KCssHandle css;                   // css handle
static long errs;                        // css api return code

/*
 * c h e c k E r r s
 *
 * This function ckecks for errors. Error messages are in case displayed
 * and program is terminated to keep the sample as simple as possible.
 */
static void checkErrs()
{
   if (errs) {
      cout << "KCss error found:" << endl;
      for (int i = 0; i < errs; i++) {
         // First we get the size of the message only so a buffer
         // large enough for the string can be allocated:
         long size, errs2;
         errs2 = KCssGetError(css, i, 0, &size); // get size of message
         if (errs2) { errs = errs2; checkErrs();  }

         // Now a buffer is allocated and the message is retrieved
         // and displayed:
         char* msg = new char[size];
         errs2 = KCssGetError(css, i, msg, &size); // get message
         if (errs2) { errs = errs2; checkErrs();  }
         cout << msg << endl;

         // the buffer is no longer required and gets discarded:
         delete [] msg;
      } // for
      exit(1);
   } // if
} // checkErrs

/*
 * c h e c k N u m b e r
 *
 * Check if string represents a number
 */
static int checkNumber(char *str)
{
   char *s = str;
   if (*s=='-' || *s=='+') s++;
   int any(0);
   while ('0'<=*s && *s<='9') { s++; any = 1; }
   if (*s=='.') s++;
   while ('0'<=*s && *s<='9') s++;
   return any && *s == 0;
} // checkNumber

/*
 * a v e r a g e
 *
 * Sample CSS function calculating the average of up 5 numbers
 */
KCssFunction average(KCssHandle aCss)
{
   char buf[40];
   long bufsiz;

   // get actual # of arguments
   bufsiz = sizeof(buf);
   KCssGet(aCss, "argCount", buf, &bufsiz);
   int argCount = atoi(buf);

   // calculate sum of all arguments
   double sum(0.0);
   for (int i = 0; i < argCount; i++) {
      // create name of parameter
      char name[4];
      sprintf(name, "p%d", i+1);

      // get argument
      bufsiz = sizeof(buf);
      if ( KCssGet(aCss, name, buf, &bufsiz) ) return; // (1)

      // check for number
      if (!checkNumber(buf)) {
         sprintf(buf, "argument p%d is no number!", i+1);
         KCssSetError(aCss, buf, -1); // (2)
      } // if

      sum += atof(buf);
   } // for

   // return result
   sprintf(buf, "%f", sum / argCount);
   KCssSetResult(aCss, buf, -1); // (2)
} // average

int main()
{
   cout << "opening css" << endl;
   errs = KCssOpen(&css,0);
   checkErrs();

   cout << endl << "get css version" << endl;
   char buf[1024];
   long bufsize(sizeof(buf));
   errs = KCssGet(css, "cssVersion", buf, &bufsize); // (1)
   checkErrs();
   cout << "  css version is " << buf << endl;

   cout << endl << "load c++ function 'average'" << endl;
   errs = KCssAddFunc(
      css,                               // handle
      module,                            // module name
      "average(const p1, "               // declaration
             "[const p2, "
              "const p3, "
              "const p4, "
              "const p5])",
      average);                          // function address
   checkErrs();

   cout << endl << "call 'average' from c++" << endl;
   static char *vals[] = {
      "3", "12", "17"
   };
   errs = KCssCall(
      css,                               // handle
      module,                            // module name
      "average",                         // function to call
      sizeof(vals)/sizeof(char*),        // # of arguments
      vals);                             // arguments
   checkErrs();

   cout << endl << "get result" << endl;
   bufsize = sizeof(buf);
   errs = KCssGetResult(css, buf, &bufsize); // (1)
   checkErrs();
   cout << "  result = " << buf << endl;

   cout << endl << "compile a script from memory" << endl;
   errs = KCssLoadScriptMem(
      css,                               // handle
      module,                            // module name

      "#loadLibrary 'KcSysLib'\n"        // the script
      ""
      "check()\n"
      "{\n"
      "   sysLog('the average of 3, 5, 12 and 7 is '\n"
      "          |average(3,5,12,7)\n"
      "   );\n"
      "}\n"
   );
   checkErrs();

   cout << endl << "call 'check' within compiled script" << endl;
   errs = KCssCall(css, module, "check", 0, 0);
   checkErrs();

   cout << endl << "closing css" << endl;
   errs = KCssClose(css);
   checkErrs();

   return 0;
} // main