database_mail.c

#include <stdio.h>
#include <stdlib.h>

#define FILEIN    "./filetxt/mail.txt"
#define FILEOUT   "./filetxt/mail"
#define START     'D'
#define END       'E'
#define STOP      'S'
#define STRLEN    1024
#define L_MIN     1
#define L_MAX     10

typedef FILE*   pfile;
typedef char*   pchar;
typedef float*  pfloat;

int stringa_contiene_char(pchar ps, char carattere)
  {
    while (*ps!='\0')
      {
        if (*ps==carattere) return 1;
        ps++;
      }
    return 0;
  }

int inputRequest(pchar question, pchar pinput, unsigned strlen)
  {
    unsigned len;
    printf("%s: ",question);
    return ((len=scanf("%s",pinput))<strlen) ? len:-1;
  }

int save_buffer (pchar nome, unsigned n, pfloat buffer, unsigned nval)
  {
    char s[STRLEN];
    pfloat p,pmax;
    pfile pfw;

    sprintf(s,"%s.%u.txt",nome,n);
    if ((pfw=fopen(s,"w"))==NULL) return 1;
    fprintf(pfw,"%u\n",nval);

    pmax=(p=buffer)+nval;
    while (p<pmax)
      {
        fprintf(pfw,"%f\n",(*p));
        p++;
      }
    fclose(pfw);
    return 0;
  }

int main(void)
  {
    int lb;
    unsigned check,nr,ns,nd,i,n;
    char s[STRLEN],stemp[STRLEN];
    pfloat buffer;
    pfile pfr;

    check=1;
    do
      {
        sprintf(stemp,"Qual e' il valore di lb? [%d,%d]",L_MIN,L_MAX);
        inputRequest(stemp,s,STRLEN);
        lb=atoi(s);
        if ((lb<L_MIN)||(lb>L_MAX)) printf("Inserisci un numero compreso tra %d e %d\n",L_MIN,L_MAX);
        else
          {
            printf("Ho ricevuto %d.\n",lb);
            check=0;
          }
      }
    while (check);

    if ((buffer=(pfloat)malloc(sizeof(float)*lb))==NULL) goto err_mem;
    if ((pfr=fopen(FILEIN,"r"))==NULL) goto err_file_r;

    ns=nd=nr=i=n=0;
    do /*in questo caso meglio usare il break*/
      {
        fscanf(pfr,"%s",s);
        nr++;
        if (stringa_contiene_char(s,START))
          {
            ns++;
            check=1;
            while (check)
              {
                fscanf(pfr,"%s",s);
                nr++;
                if (!stringa_contiene_char(s,END))
                  {
                    buffer[i]=atof(s);
                    nd++;
                    printf("nr=%u, ns=%u, nd=%u -> Letto: %.2f\n",nr,ns,nd,buffer[i]);
                    i++;
                    if (i>=lb)
                      {
                        save_buffer(FILEOUT,n,buffer,i);
                        printf("Scrivo il file: %s.%u.txt\n",FILEOUT,n);
                        n++;
                        i=0;
                      }
                  }
                else check=0;
              }
          }
      }
    while (!stringa_contiene_char(s,STOP));
    if (i)
      {
        save_buffer(FILEOUT,n,buffer,i);
        printf("Scrivo il file: %s.%u.txt\n",FILEOUT,n);
      }

    fclose(pfr);

    return 0;
    err_file_r:
      printf("Errore lettura file\n"); return EXIT_FAILURE;
    err_mem:
      printf("Errore memoria\n"); return EXIT_FAILURE;
}