ini.c

国外网站上的一些精典的C程序

                  };

                  /*
                  ** Variable wasn't found.  If we don't want it,
                  ** then ignore it
                  */
            }
            case NotInSection:
                  break;  /* Not interested in this line */

            case NewSection:
                  break;  /* Who cares? It's not our section */

            case FoundSection:
                  break;  /* We found our section! */

            case LeavingSection:
                  break;  /* We finished our section! */
            }

            if (-1 == retval)
                  break;
      }

      if (ferror(CfgFile))
      {
            fclose(CfgFile);
            return -2;
      }
      else
      {
            fclose(CfgFile);
            return retval;
      }
}

/*
**  SearchCfg() - Search an .ini / .cfg file for a specific single datum.
**
**  Parameters: 1 - File name.
**              2 - Section name.
**              3 - Variable to find.
**              4 - Pointer to variable's storage.
**              5 - Type of vatiable.
**
**  Returns:  1 if succesful
**            0 if section/variable not found
**           -1 if invalid type spec
**           -2 for file error
*/

int SearchCfg(const char *FileName,
              char *SectionName,
              char *VarName,
              void *DataPtr,
              enum CfgTypes VarType
             )
{
      struct CfgStruct MyVars[2];

      MyVars[0].Name    = VarName;
      MyVars[0].DataPtr = DataPtr;
      MyVars[0].VarType = VarType;

      MyVars[1].Name = MyVars[1].DataPtr = NULL;

      return ReadCfg(FileName, SectionName, MyVars);
}

/*
**  UpdateCfg() - This will update a variable in a specific section in your
**                .ini file. It will do so safely by copying it to a new file,
**                and when finished, will delete the old one and rename the
**                new one to the correct name. If any fatal error occurs, it
**                will return a -1 to indiate failure. I generally don't care
**                why it failed, just knowing that it failed is usually enough.
**
**  Paramters: 1 - File name.
**             2 - Section name.
**             3 - Variable tag.
**             4 - Pointer to textual representation of the variable's value.
**
**  Returns: -1 if a file error occurred, else 0.
**
**  Notes: 1. If the section doesn't yet exist in the file, it will be added.
**         2. If the variable doesn't yet exist in the file, it will be added.
**         3. New variables are created at the end of existing sections, or
**            on the last line before the first section name in the case where
**            the section name is "".
**         4. New sections are created at the end of the file.
*/

int UpdateCfg(const char *FileName,
              char *SectionName,
              char *VarWanted,
              char *NewData)
{
      FILE *CfgFile;
      char line[BUFFERSIZE];
      char SectionWanted[BUFFERSIZE];
      char CurrentSection[BUFFERSIZE];
      enum LineTypes linetype;
      char var[BUFFERSIZE];
      char data[BUFFERSIZE];
      char TempFileName[FILENAME_MAX];
      FILE *NewCfgFile;
      int Error = 0;
      int updated = 0;

      CfgFile = cant((char *)FileName, "r");

      strcpy(TempFileName, FileName);
      chgext(TempFileName, NULL, "tmp");
      NewCfgFile = cant(TempFileName, "w");

      strcpy(CurrentSection, "[]");
      sprintf(SectionWanted, "[%s]", SectionName);

      while (EOF != ReadLine(CfgFile, line))
      {
            linetype = SectionLine(line, SectionWanted, CurrentSection);
            switch (linetype)
            {
            case InSection:              /* In our section, parse it. */
                  ParseLine(line, var, data);
                  if ((StrEq(var, VarWanted)) && (!updated))
                  {
                        strncpy(data, NewData, BUFFERSIZE);
                        data[BUFFERSIZE-1] = NUL;
                        updated = 1;
                  }
                  fprintf(NewCfgFile, "%s = %s\n", var, data);
                  break;

            case EmptyLine:         /* Fall Through.  Just copy it. */
            case CommentLine:       /* Fall Through.  Just copy it. */
            case NotInSection:      /* Fall Through.  Just copy it. */
            case NewSection:        /* Fall Through.  Just copy it. */
            case FoundSection:      /* Fall Through.  Just copy it. */
                  fprintf(NewCfgFile, "%s\n", line);
                  break;

            case LeavingSection:    /* Leaving section, may have to add it */
                  if (!updated)     /* Variable wasn't found, we have      */
                  {                 /* to add it.                          */
                        fprintf(NewCfgFile, "%s = %s\n", VarWanted, NewData);
                        updated = 1;
                  }
                  /*
                  ** Now print current line
                  */

                  fprintf(NewCfgFile, "%s\n", line);
                  break;
            }
      }

      /*
      ** Our section may not have even been there, in which case we have
      ** to add both the variable and the section itself.
      */

      if (!updated)
      {     /* We may have hit EOF while still in our section. */
            /* If so, we don't need to add the section header. */
            if (!StrEq(CurrentSection, SectionWanted))
                  fprintf(NewCfgFile, "%s\n", SectionWanted);
            fprintf(NewCfgFile, "%s = %s\n", VarWanted, NewData);
      }

      if (ferror(CfgFile))
            Error = -1;
      if (ferror(NewCfgFile))
            Error = -1;
      fclose(CfgFile);
      fclose(NewCfgFile);

      if (!Error)
      {
            if (remove(FileName))
                  return -1;
            if (rename(TempFileName, FileName))
                  return -1;
      }
      return Error;
}

#ifdef TEST

#include <stdlib.h>

#if defined(MSDOS) || defined (_MSDOS_)
 #define PINI_fname "prices.ini"
#else
 #define PINI_fname "/home/mars_nwe/engr/disp/prices.ini"
#endif

FILE *log_ = stderr;

main()
{
      char        Line[INI_LINESIZE];
      int         Int;
      long        Long;
      double      Double;
      Boolean_T   Bool;
      struct      CfgStruct this_var;
      FILE*       tst;
      long        prices[2];


      /*
      **  First work with a test file
      */
      tst = cant("test.ini", "w");
      fputs("[Section 1]\n", tst);
      fputs("[Section 2]\n", tst);
      fputs("[Section 3]\n", tst);
      fputs("[Section 4]\n", tst);
      fputs("[Section 5]\n", tst);
      fputs("[Section 6]\n", tst);
      fclose(tst);
      puts("Updating the test configuration file");

      puts("Updating section 1");
      UpdateCfg("test.ini", "Section 1", "string #1", "section 1 test");
      puts("Updating section 2");
      UpdateCfg("test.ini", "Section 2", "short #2", "2");
      puts("Updating section 3");
      UpdateCfg("test.ini", "Section 3", "long #3", "3");
      UpdateCfg("test.ini", "Section 4", "double #4", "4.4");
      UpdateCfg("test.ini", "Section 5", "boolean #5", "Y");
      UpdateCfg("test.ini", "Section 6", "boolean #6", "N");
      UpdateCfg("test.ini", "", "global string", "\"Hello, world!\" ;Comment");

      puts("I've finished the updates, now to try to get the data back");

      this_var.Name    = "global string";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(0) returned %d; Line=\n",
             ReadCfg("test.ini", "", &this_var));
      puts(Line);

      this_var.Name    = "string #1";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(1) returned %d; Line=\n",
             ReadCfg("test.ini", "Section 1", &this_var));
      puts(Line);

      this_var.Name    = "short #2";
      this_var.DataPtr = &Int;
      this_var.VarType = Cfg_Short;
      printf("ReadCfg(2) returned %d; Value= ",
             ReadCfg("test.ini", "Section 2", &this_var));
      printf("%d\n", Int);

      this_var.Name    = "long #3";
      this_var.DataPtr = &Long;
      this_var.VarType = Cfg_Long;
      printf("ReadCfg(3) returned %d; Value = ",
             ReadCfg("test.ini", "Section 3", &this_var));
      printf("%ld\n", Long);

      this_var.Name    = "double #4";
      this_var.DataPtr = &Double;
      this_var.VarType = Cfg_Double;
      printf("ReadCfg(4) returned %d; Value = ",
             ReadCfg("test.ini", "Section 4", &this_var));
      printf("%f\n", Double);

      this_var.Name    = "boolean #5";
      this_var.DataPtr = &Bool;
      this_var.VarType = Cfg_Boolean;
      printf("ReadCfg(5) returned %d; Value = ",
             ReadCfg("test.ini", "Section 5", &this_var));
      printf("%c\n", Bool ? 'T' : 'F');

      this_var.Name    = "boolean #6";
      this_var.DataPtr = &Bool;
      this_var.VarType = Cfg_Boolean;
      printf("ReadCfg(6) returned %d; Value = ",
             ReadCfg("test.ini", "Section 6", &this_var));
      printf("%c\n", Bool ? 'T' : 'F');

      /*
      **  Look for non-existant sections and/or variables
      */

      Line[0] = NUL;
      this_var.Name    = "string #99";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(99) returned %d; Line=\n",
             ReadCfg("test.ini", "Section 99", &this_var));
      puts(Line);

      Line[0] = NUL;
      this_var.Name    = "string #99";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(0/99) returned %d; Line=\n",
             ReadCfg("test.ini", "", &this_var));
      puts(Line);

      Line[0] = NUL;
      this_var.Name    = "string #99";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(1/99) returned %d; Line=\n",
             ReadCfg("test.ini", "Section 1", &this_var));
      puts(Line);

      Line[0] = NUL;
      this_var.Name    = "string #1";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(1/100) returned %d; Line=\n",
             ReadCfg("test.ini", "Section 100", &this_var));
      puts(Line);

      /*
      **  Next, add a section and new variables
      */

      UpdateCfg("test.ini", "", "new global variable", "abc");
      UpdateCfg("test.ini", "Section -1", "new variable", "xyz");
     
      /*
      **  Next work with a sample real PRICES.INI file
      */

      this_var.Name    = "Price of #1";
      this_var.DataPtr = &prices[0];
      this_var.VarType = Cfg_Long;
      printf("ReadCfg(1) returned %d; Value = ",
             ReadCfg(PINI_fname, "", &this_var));
      printf("%ld\n", prices[0]);

      this_var.Name    = "Price of #2";
      this_var.DataPtr = &prices[1];
      this_var.VarType = Cfg_Long;
      printf("ReadCfg(2) returned %d; Value = ",
             ReadCfg(PINI_fname, "", &this_var));
      printf("%ld\n", prices[1]);

      UpdateCfg("prices.ini", "", "Price of #2", "999");

      this_var.Name    = "Price of #2";
      this_var.DataPtr = &prices[1];
      this_var.VarType = Cfg_Long;
      printf("ReadCfg(2) returned %d; Value = ",
             ReadCfg(PINI_fname, "", &this_var));
      printf("%ld\n", prices[1]);

      UpdateCfg(PINI_fname, "", "Price of #2", "389");

      this_var.Name    = "Price of #2";
      this_var.DataPtr = &prices[1];
      this_var.VarType = Cfg_Long;
      printf("ReadCfg(2) returned %d; Value = ",
             ReadCfg(PINI_fname, "", &this_var));
      printf("%ld\n", prices[1]);

      /*
      **  Finally, try an invalid file name
      */

      this_var.Name    = "global string";
      this_var.DataPtr = Line;
      this_var.VarType = Cfg_String;
      printf("ReadCfg(0) returned %d; Line=\n",
             ReadCfg("none.ini", "", &this_var));
      puts(Line);

      return EXIT_SUCCESS;
}

#endif