문자열 문제점..

#define BUFSIZE 1024
#define LINESIZE 100
#define LISTENQ 20
#define MODE 0777
#define MEMBERS "USERS"
#define T_MEMBERS ".USERS"
#define MAXSTRBUF 100
 
#define D_MAILBOX "mailbox"
#define F_MAIL_LIST "mail_list"
 
char serverName[50];
 
void trim(char s[])
{
    int i,len;
    len = strlen(s);
    for(i=0; i<len; i++){
        if( (s[i] == ' ')  || (s[i] == '\t') ||
            (s[i] == '\r') || (s[i] == '\n'))
            break;
    }
    s[i]='\0';
}
 
char * getNowTime()
{
 
	time_t now;
	struct tm * theTime;
	char *t = (char *)malloc(sizeof(char) * MAXSTRBUF);
 
	time(&now);
	theTime=gmtime(&now);
 
	sprintf(t,"%d-%d-%d %d:%d:%d", theTime->tm_year+1900,
						   	 theTime->tm_mon+1,
						   	 theTime->tm_mday,
						   	 theTime->tm_hour,
						   	 theTime->tm_min,
						   	 theTime->tm_sec);
 
	t=(char *)realloc(t,strlen(t));
 
	return t;
}
 
char *getNewMailId()
{
 
	time_t now;
	struct tm * theTime;
	char *id= (char *)malloc(sizeof(char)*MAXSTRBUF);
	memset(id,0,sizeof(char)*MAXSTRBUF);
	time(&now);
	theTime=gmtime(&now);
	theTime->tm_mon++;
	int mon  = (theTime->tm_mon  < 10) ? theTime->tm_mon+10  : theTime->tm_mon;
	int mday = (theTime->tm_mday < 10) ? theTime->tm_mday+11 : theTime->tm_mday;
	int hour = (theTime->tm_hour < 10) ? theTime->tm_hour+10 : theTime->tm_hour;
	int min  = (theTime->tm_min  < 10) ? theTime->tm_min+10  : theTime->tm_min;
	int sec  = (theTime->tm_sec  < 10) ? theTime->tm_sec+10  : theTime->tm_sec;
 
	sprintf(id,"%4d%2d%2d%2d%2d%2d", theTime->tm_year+1900, mon, mday, hour, min, sec);
 
	id = (char *)realloc(id, strlen(id));
 
	printf("[%s]\n\n",id);
	return id;
}
 
 
// r=-1  not valid 
// r=0   valid
int IsValidId(char *user, char *id)
{
 
	FILE *fp;
 
	char id_buf[MAXSTRBUF];
	int len=strlen(id);
	int r=0;
 
	char *mail_list_path_file = (char *)malloc(sizeof(char)*MAXSTRBUF);	
	sprintf(mail_list_path_file, "%s/%s/%s", D_MAILBOX, user,F_MAIL_LIST);	
 
	if( (fp = fopen(mail_list_path_file,"r")) == NULL) 
		error_at_line(1, errno, __FILE__,__LINE__,"Error: file open %s",mail_list_path_file);
 
	while( (fgets(id_buf, MAXSTRBUF, fp)) != NULL){
		if( (strncmp(id_buf, id, len)) == 0)
			r=-1; break;
	}
	fclose(fp);
 
 
 
	return (r);
}
 
void sendMail(char *from, char *to, char *subject, char *body)
{
	FILE * fp_mail_list; 	// a file pointer for the mail_list file
	FILE * fp_mail_body; 	// a file pointer for the mail body file
 
	char *time; 			// time pointer
	char *id; 				// id pointer
	int n;
	time = getNowTime(); 	// get current time
 
	id = getNewMailId(); 	// get a new mail id	
 
	while(1){ 
		if((n=IsValidId(to, id)) < 0 )		
			id = getNewMailId(); 	// get a new mail id	
		else
			break;
 
	}
 
 
	char *mail_list_path_file = (char *)malloc(sizeof(char)*MAXSTRBUF);
	char *mail_list_body_file = (char *)malloc(sizeof(char)*MAXSTRBUF);
	char *mail_list_content   = (char *)malloc(sizeof(char)*MAXSTRBUF);
 
	memset(mail_list_path_file, 0,sizeof(char)*MAXSTRBUF);
	memset(mail_list_body_file, 0,sizeof(char)*MAXSTRBUF);
	memset(mail_list_content, 0,sizeof(char)*MAXSTRBUF);
 
	// to set the mail list path file
	sprintf(mail_list_path_file, "%s/%s/%s", D_MAILBOX, to, F_MAIL_LIST);	
	sprintf(mail_list_body_file, "%s/%s/%s", D_MAILBOX, to, id);			
	sprintf(mail_list_content,   "%s\t%s\t%s\t%s\n", id, from, time, subject);
 
	mail_list_path_file = (char *)realloc(mail_list_path_file, strlen(mail_list_path_file));
	mail_list_body_file = (char *)realloc(mail_list_body_file, strlen(mail_list_body_file));
	mail_list_content   = (char *)realloc(mail_list_content,   strlen(mail_list_content));
 
 
	printf("[%s]\n[%s]\n[%s]\n",mail_list_path_file,mail_list_body_file,mail_list_content);
 
 
	if( (fp_mail_list=fopen(mail_list_path_file, "a+")) == NULL)
		error_at_line(1, errno, __FILE__,__LINE__,"Error: file open %s",mail_list_path_file);
 
	fputs(mail_list_content, fp_mail_list);
	fclose(fp_mail_list);
 
	if( (fp_mail_body=fopen(mail_list_body_file, "w")) == NULL)
		error_at_line(1, errno, __FILE__,__LINE__,"Error: file open %s",mail_list_path_file);
 
	fputs(body, fp_mail_body);
	fclose(fp_mail_body);
 
	free(time);
	free(id);
	free(mail_list_path_file);
	free(mail_list_body_file);
	free(mail_list_content);		
 
}
 
int main()
{
	//int r;
	char *subject="Welcome";
	char *body="This is a simple email system\n"
			   "This beta test version is currently running on the linux sytem\n"
			   "If you have any questions Please, feel free ask me.\n\n"
			   "Thank you very much for choosing this system\n"
			   " by admin\n";
 
	sendMail("admin", "papa1", subject, body);
	return 0;
}