CHECKSUM MD5 D'UN FICHIER C

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>

#include "md5.h"
//buffer maximum
#define MAX_BUF 1024
//lire le fichier
char *readFile( FILE  *fp);
//generer le hash et imprimer dans CHECKSUM.MD5
bool  hash_md5_file(const char  *file);
//strcpy prudent
char *strCopy( char * str );

int main(int argc, char *argv[])
{
  if(!hash_md5_file("../main.c")){
                                          perror("fichier:");
}else{
      puts("Hashage...OK");
      }
  #ifdef WIN32
  getch();
  #endif	
  return 0;
}
char *readFile( FILE *fp )
{
  if( !fp )
  {
    return NULL;
  }

  char *output = NULL;
  char buf[ MAX_BUF ];
  int bytes, byteCount = 0;
  
  memset( buf, 0, sizeof( buf ) );
  
  while( ( bytes = fread( buf, sizeof( char ), sizeof( buf ) - 1, fp ) ) > 0 )
  {
    if( !output )
    {
      /* allocate output */
      output = ( char * )malloc( bytes + 1 );
      memcpy( output, buf, bytes + 1 );
    }
    else
    {
      /* deja existe - reallocate! */
      
      
      char *oldStr = strCopy( output );
      output = ( char * )realloc( output, byteCount + bytes + 1 );
      memcpy( output, oldStr, byteCount );
      
      free( oldStr );
      memcpy( output + byteCount, buf, bytes + 1 );
    }
  
    byteCount += bytes;
    memset( buf, 0, sizeof( buf ) );
  }
  
  return output;
}
bool hash_md5_file(const char *file)
{
     /*                  ****Lire le fichier
                         ***retourner un pointeur qui contient 
                         les donnees
                         ***md5 hash
                         ***imprimer le hex code dans le fichier CHECKSUM.MD5
                         */
     FILE                *fp,*out;
     char                *data;
     char                output[]="CHECKSUM.MD5";
     static  char   HEX_DATA[31];
     md5_state_t     state;
     md5_byte_t      digest[16];
     if(file==NULL){
                    return false;
                    }
     fp=fopen(file,"rb");
     if(fp==NULL){
                  return false;
                  }
     data=readFile(fp); //malloc and memset sont effectuer dans ===>readFile()
     if(data==NULL){
                    return false;
                    }
            //MD5 HASH ALGORITHM
            md5_init(&state);
            md5_append(&state,(const md5_byte_t  *)data,strlen(data));
            md5_finish(&state,digest);
            int i=0;
            for(i;i<16;i++){
                 snprintf(HEX_DATA+i*2,sizeof(HEX_DATA),"%02x",digest[i]); 
                 }
                 fclose(fp);
           
              out=fopen(output,"a+");
              if(out==NULL){
                            return false;
                            }
                            fprintf(out,"MD5 (%s)= ",file);
                            fprintf(out,"%s\n",HEX_DATA);
                            //clean && close
                            fflush(out);
                            fclose(out);  
      
     return true;
}
char *strCopy( char * str )
{
  if( !str )
  {
    return NULL;
  }
  
  char *n = ( char * )malloc( strlen( str ) + 1 );
  memcpy( n, str, strlen( str ) + 1 );
  
  return n;
}