How to create Antivirus using C++ programming language
In this article we are going to see how to create antivirus tool - console user interface (CUI).This tool has own scanning algorithm to identify malicious code in each files during scan. The core idea is to search the virus signatures in all files and directory's. Usually, 90% of viruses/worm having own signature (Some repeat text found/visable in all affected files (eg .exe, .vbs, .bat etc..) or archive files) and remain 10% Viruses are identified based on execution behavior. Here I wrote the scripts based on signature-based scan algorithm and I stored the identify Virus signatures in separate organizes flat files. Antivirus Tool execution starts from below script.little17.cpp
1 #include<iostream.h>
2 #include<conio.h>
3 #include<process.h>
4 #include<dir.h>
5 #include<dirent.h>
6 #include<alloc.h>
7 #include<io.h>
8
9 FILE *dp;
10 unsigned char ch;
11 struct ffblk dfile;
12 int i,j=0,k=0,total,mode=0;
13 char *sign = (char *) malloc(9);
14 char *drive = (char *) malloc(27);
15 char *drivefound= (char *) malloc(27);
16
17 void scan();
18 void info();
19 void dump(char *);
20
21 void main(int a,char *arg[],char *env[])
22 {
23 if(access"cscan.exe",0!=0)
24 {
25 free(drive);
26 free(drivefound);
27 exit(0);
28 }
29
30 if(access"hscan.exe",0!=0)
31 {
32 free(drive);
33 free(drivefound);
34 exit(0);
35 }
36 char *dirlist = (char *) malloc(53);
37
38 i = findfirst("*.db",&dfile,0);
39 while (!i)
40 {
41 dp = fopen(dfile.ff_name,"rb");
42 fread(sign,8,1,dp);
43 if(!strcmpsign,"LITTLE17")
44 {
45 j=1;
46 fclose(dp);
47 break;
48 }
49 else
50 fclose(dp);
51 i=findnext(&dfile);
52 }
53
54 if(j!=1)
55 {
56 cout<<"\nError : Supporting database not found";
57 free(drive); free(drivefound);
58 getch();
59 exit(0);
60 }
61
62 scan();
63 while(1)
64 {
65 while(1)
66 {
67 cout<<"\nSystem: Drive Found\n\n\n";
68 for(i=0;i<total;i++)
69 cout<<drivefound[i]<<": ";
70
71 while(1)
72 {
73 cout<<"\n\nPress 1-Cool Mode & 2-Hot Mode";
74 cout<<"\n\nEnter your mode:";
75 ch=getche();
76 if(ch==49)
77 { mode=49; break; }
78 else if(ch==50)
79 { mode=50; break; }
80 else
81 {
82 clrscr();
83 cout<<"\nWarning: Sorry your mode is invalid";
84 cout<<"\nWarning: Please select right mode\n";
85 cout<<"\nSystem: Drive Found\n\n\n";
86 for(i=0;i<total;i++)
87 cout<<drivefound[i]<<": ";
88 }
89 }
90
91 cout<<"\n\nEnter drive to scan:";
92 cin>>dirlist;
93 j=strlen(dirlist);
94 dump(dirlist);
95
96 if(j==5 && !strcmpdirlist,"RESET")
97 scan();
98
99 else if(j==3 && !strcmpdirlist,"ALL")
100 {
101 char *passdata = (char *) malloc(13);
102 strcpy(passdata,"XYVRGRASEWXC");
103 for(j=0;j<total;j++)
104 {
105 *(passdata+0)=drivefound[j];
106 arg[1]=passdata;
107 if(mode==49)
108 spawnve(P_WAIT,"CSCAN.EXE",arg,env);
109 if(mode==50)
110 spawnve(P_WAIT,"HSCAN.EXE",arg,env);
111 }
112 free(passdata);
113 }
114
115 else if(j==4 && !strcmpdirlist,"EXIT")
116 {
117 free(drive);
118 free(drivefound);
119 free(dirlist);
120 exit(0);
121 }
122 else
123 break;
124 }
125
126 if(j%2!=0)
127 {
128 for(i=1;i<j;i=i+2)
129 {
130 if (dirlist[i]!='\,')
131 break;
132 }
133
134 if(i>=j)
135 {
136 k=strlen(dirlist);
137 char *passdata = (char *) malloc(13);
138 strcpy(passdata,"XYVRGRASEWXC");
139 for(j=0;j<k;j=j+2)
140 {
141 *(passdata+0)=dirlist[j];
142 arg[1]=passdata;
143 if(mode==49)
144 spawnve(P_WAIT,"CSCAN.EXE",arg,env);
145 if(mode==50)
146 spawnve(P_WAIT,"HSCAN.EXE",arg,env);
147 }
148 free(passdata);
149 }
150 else
151 { clrscr();
152 cout<<"\nWarning: Comma missing between drives";
153 cout<<"\nEg: C,F,G - Valid";
154 cout<<"\nEg: CFG - Invalid\n";
155 info();
156 }
157 }
158 else
159 {
160 clrscr();
161 cout<<"\nWarning: Command should be odd size";
162 cout<<"\nEg: C,F,G - Valid";
163 cout<<"\nEg: C,FG - Invalid\n";
164 info();
165 }
166 clrscr();
167 }
168 }
169
170 void scan()
171 {
172 j=0;
173 char dir[]="VOL X:";
174 clrscr();
175 cout<<"\nSystem: Welcome to Little17 Antivirus";
176 for(i=0;i<=25;i++)
177 {
178 strcpy(drive,"ABCDEFGHIJKLMNOPQRSTUVWXYZ");
179 dir[4]=drive[i];
180 ch=system(dir);
181 clrscr();
182 if(ch==0)
183 {
184 drivefound[j]=drive[i];
185 j++;
186 }
187 drivefound[j]='\0';
188 }
189 total=j;
190 }
191
192 void info()
193 {
194 cout<<"\n\nInformation:\n";
195 cout<<"\n1.Hello user i give information to use this software";
196 cout<<"\n2.Suppose you want to scan particular drive";
197 cout<<"\n Eg: type \" C,D,W,I \" ";
198 cout<<"\n3.If you scan all drive type \" ALL \" ";
199 cout<<"\n4.Want to close type \" EXIT \" ";
200 getch();
201 }
202
203 void dump(char *dump)
204 {
205 for(i=0;i<j;i++)
206 {
207 if( dump[i]!='\,' && dump[i]>=97 && dump[i]<=122 )
208 dump[i]=dump[i]-32;
209 }
210 }updater.cpp
1 #include<iostream.h>
2 #include<conio.h>
3 #include<string.h>
4 #include<process.h>
5 #include<io.h>
6 #include<alloc.h>
7 #include<dir.h>
8 #include<ctype.h>
9
10 struct ffblk dblist,list;
11 FILE *temp_p,*dp,*vp;
12 char *sign = (char *) malloc(9);
13
14 char ch;
15 unsigned int count,first=0,found=0;
16 unsigned long int start,udata1,udata2,udata3;
17
18 void set_virus_name(char *);
19 void update_signature(char *,char *,int,int);
20 void set_data(char *,char *,int);
21
22 void main()
23 {
24 clrscr();
25 char *vfile = (char *) malloc(40);
26 char *dfile = (char *) malloc(40);
27 cout<<"\nSystem: Enter the infected filename: ";
28 cin>>vfile;
29
30 if(accessvfile,0!=0)
31 {
32 cout<<"\nError : File not exist";
33 free(sign);
34 free(vfile);
35 free(dfile);
36 getch();
37 exit(0);
38 }
39 strcpy(sign,"LITTLE17");
40
41 udata1 = findfirst("*.db",&dblist,0);
42 while (!udata1)
43 {
44 first=1;
45 temp_p= fopen(dblist.ff_name,"r");
46 fread(sign,8,1,temp_p);
47 if(!strcmpsign,"LITTLE17");
48 update_signature(vfile,dblist.ff_name,1,0);
49 fclose(temp_p);
50 udata1=findnext(&dblist);
51 }
52
53 if(first==0)
54 {
55 cout<<"\nSystem: Enter the database name :";
56 cin>>dfile;
57 udata1=strlen(dfile);
58 if(dfile[udata1-3]=='\.'&& dfile[udata1-2]=='D'||dfile[udata1-2]=='d' && dfile[udata1-1]=='B'||dfile[udata1-1]=='b' )
59 update_signature(vfile,dfile,0,1);
60 else
61 {
62 cout<<"\n\nError : Create .DB extension file type";
63 free(sign);
64 free(vfile);
65 free(dfile);
66 getch();
67 exit(0);
68 }
69 }
70 else
71 {
72 if(found==0)
73 {
74 cout<<"\nSystem: Enter the database name :";
75 cin>>dfile;
76 udata1=strlen(dfile);
77 if(dfile[udata1-3]=='\.'&& dfile[udata1-2]=='D'||dfile[udata1-2]=='d' && dfile[udata1-1]=='B'||dfile[udata1-1]=='b' )
78 {
79 if(!accessdfile,0)
80 {
81 dp = fopen(dfile,"r");
82 fread(sign,8,1,dp);
83 fclose(dp);
84 if(!strcmpsign,"LITTLE17")
85 update_signature(vfile,dfile,1,1);
86 else
87 {
88 cout<<"\n\nError : Database not supported with "<<vfile;
89 free(sign);
90 free(vfile);
91 free(dfile);
92 exit(0);
93 }
94
95 }
96 else
97 update_signature(vfile,dfile,0,1);
98 }
99 else
100 {
101 cout<<"\n\nError: Create .DB extension file type";
102 free(sign);
103 free(vfile);
104 free(dfile);
105 exit(0);
106 }
107
108 }
109 }
110 free(sign);
111 free(vfile);
112 free(dfile);
113 getch();
114 }
115
116 void update_signature(char *vfile,char *dfile,int check,int add)
117 {
118 if(check==1)
119 {
120 char *temp = (char *) malloc(strlendfile+1);
121 strcpy(temp,dfile);
122 char *turn = (char *) malloc(40+2+400+1);
123
124 dp = fopen(dfile,"r");
125 fread(sign,8,1,dp);
126 fread(&start,sizeofstart,1,dp);
127 while(1)
128 {
129 udata1=0;
130 while(1)
131 {
132 ch=fgetc(dp);
133 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t')
134 {
135 if(ch==20)
136 udata2=udata1;
137 if(ch!=22)
138 {
139 turn[udata1]=ch;
140 udata1=udata1+1;
141 continue;
142 }
143 else
144 break;
145 }
146 }
147 turn[udata1]='\0';
148 udata2=udata2+1;
149 udata3=udata2;
150
151 count=0;
152 udata1=0;
153 udata2=udata3;
154 vp=fopen(vfile,"r");
155 findfirst(vfile,&list,0);
156 while(udata1<list.ff_fsize)
157 {
158
159 fseek(vp,udata1,SEEK_SET);
160 ch=fgetc(vp);
161 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t' && ch!= 20 && ch!= 22)
162 {
163 if(ch!=turn[udata2])
164 {
165 if(count>=2)
166 udata1=udata1-count;
167 count=0;
168 udata2=udata3;
169 }
170 else
171 {
172 count=count+1;
173 udata2=udata2+1;
174 if(turn[udata2]==0)
175 {
176
177 cout<<"\n\n\nError : Unsuccessfully ! ";
178 cout<<"\n\nError : Virus were Already added on "<<temp;
179 cout<<" [ ";
180 udata3--;
181 for(count=0;count<udata3;count++)
182 {
183 if(turn[count]!=32)
184 cout<<turn[count];
185 else
186 cout<<" ";
187 }
188 cout<<" ]";
189 found=1;
190 break;
191 }
192 }
193 }
194 fflush(vp);
195 udata1=udata1+1;
196
197 }
198 fclose(vp);
199
200 if(found==1)
201 break;
202 ch=fread(&start,sizeofstart,1,dp);
203 if(ch+1==1)
204 break;
205 }
206 fclose(dp);
207 free(temp);
208 free(turn);
209
210 if(found==0&&add==1)
211 {
212 set_data(vfile,dfile,check);
213 }
214 }
215 else
216 {
217 set_data(vfile,dfile,check);
218 }
219 }
220
221
222 void set_data(char *vfile,char *dfile,int check)
223 {
224 char *temp = (char *) malloc(40);
225 cout<<"\n\nSystem: Set the name of virus :";
226 gets(temp);
227 cout<<"\nEnter first index :";
228 cin>>udata1;
229 start=udata1;
230 cout<<"\nEnter last index :";
231 cin>>udata2;
232 char *vdata = (char *) malloc(udata2-udata1+2+2+2+1);
233 vdata[0]=20;
234 udata3=1;
235
236 vp=fopen(vfile,"r");
237 while(udata1<=udata2)
238 {
239 fseek(vp,udata1,SEEK_SET);
240 ch=getc(vp);
241 cout<<udata1<<" "<<ch<<"\n";
242 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t' && ch!=20 && ch!=22)
243 {
244 vdata[udata3]=ch;
245 udata3=udata3+1;
246 vdata[udata3]='\0';
247 }
248 udata1=udata1+1;
249 }
250 fclose(vp);
251 vdata[udata3+1]='\0';
252 vdata[udata3]=22;
253
254 dp=fopen(dfile,"a+");
255 if(check==0)
256 fwrite(sign,8,1,dp);
257 fwrite(&start,sizeofstart,1,dp);
258 fwrite(temp,strlentemp,1,dp);
259 free(temp);
260 fwrite(vdata,strlenvdata,1,dp);
261 free(vdata);
262 fclose(dp);
263 cout<<"\n\nSystem: Successfully Added on "<<dfile;
264 }cscan.cpp
1 #include<iostream.h>
2 #include<conio.h>
3 #include<dirent.h>
4 #include<dir.h>
5 #include<process.h>
6 #include<string.h>
7 #include<stdio.h>
8 #include<io.h>
9 #include<dos.h>
10 #include<sys/stat.h>
11
12 FILE *dp,*vp;
13 unsigned int count;
14 struct ffblk dfile;
15 struct ffblk vfile;
16 char base,ch,found=0;
17 char present[MAXPATH];
18 char *sign = (char *) malloc(9);
19 unsigned long int start,udata1,udata2,udata3;
20
21 int next_directory(char *);
22 void scan_directory(char *);
23 void dump(char *);
24
25
26 void main(int account,char *arg[],char *env[])
27 {
28 if( account==2 && !strcmparg[1]+1,"YVRGRASEWXC" )
29 {
30 DIR *dir;
31 struct dirent *temp;
32 for(found=0;found<32;found++)
33 {
34 if(env[found][0]=='S' && env[found][1]=='y' && env[found][12]!=':')
35 break;
36 }
37
38 clrscr();
39 base=env[found][12];
40 found=0;
41
42 getcwd(present,MAXPATH);
43 char drive[]="X:\\";
44 drive[0]=*(arg[1]+0);
45 if (dir = opendirdrive == NULL)
46 {
47 cout<<"\nError : Device not found";
48 free(sign);
49 sleep(2);
50 exit(0);
51 }
52
53 scan_directory(drive);
54 while (temp = readdirdir != NULL)
55 {
56 char *directory = (char *) malloc(3+strlentemp->d_name+1);
57 strcpy(directory,drive);
58 strcat(directory,temp->d_name);
59 next_directory(directory);
60 free(directory);
61 }
62 free(sign);
63 closedir(dir);
64 clrscr();
65 }
66 }
67
68 int next_directory(char *path)
69 {
70 int count=0;
71 DIR *dirtemp;
72 char *hold,*temp;
73 struct dirent *ptemp;
74
75 hold=path;
76 if (dirtemp = opendirpath != NULL)
77 scan_directory(path);
78 else
79 return 0;
80
81 while (ptemp = readdirdirtemp != NULL)
82 {
83 char *directory = (char *) malloc(1+strlenptemp->d_name+1);
84 directory[0]='\\';
85 strcpy(directory+1,ptemp->d_name);
86 if(directory[1]!='\.')
87 {
88 count=strlen(hold);
89 temp = (char *) malloc(strlenhold+strlendirectory+1);
90 strcpy(temp,hold);
91 strcat(temp,directory);
92 free(directory);
93 if(opendirtemp!=NULL)
94 next_directory(temp);
95 temp[count]='\0';
96 hold=temp;
97 }
98 else
99 free(directory);
100 }
101 closedir(dirtemp);
102 return 0;
103 }
104
105 void scan_directory(char *tempo)
106 {
107 char *dbsign = (char *) malloc(40+2+400+1);
108 udata1 = findfirst("*.db",&dfile,0x02);
109 while (!udata1)
110 {
111 dp = fopen(dfile.ff_name,"r");
112 fread(sign,8,1,dp);
113 if(strcmpsign,"LITTLE17"==0)
114 {
115 fread(&start,sizeofstart,1,dp);
116 while(1)
117 {
118 udata1=0;
119 while(1)
120 {
121 ch=fgetc(dp);
122 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t')
123 {
124 if(ch==20)
125 udata2=udata1;
126 if(ch!=22)
127 {
128 dbsign[udata1]=ch;
129 udata1=udata1+1;
130 dbsign[udata1]='\0';
131 continue;
132 }
133 else
134 break;
135 }
136 }
137 udata2=udata2+1;
138 udata3=udata2;
139
140 if(present[0]==tempo[0])
141 chdir(tempo);
142 else
143 {
144 setdisk(tempo[0]-65);
145 chdir(tempo);
146 }
147
148 udata1 = findfirst("*.*",&vfile,0x02);
149 while (!udata1)
150 {
151 clrscr();
152 cout<<"\nNow scanning:"<<vfile.ff_name;
153 cout<<"\nLocation "<<tempo;
154
155 vp=fopen(vfile.ff_name,"r");
156 udata1=start+(strlendbsign)-udata1;
157 if( vp!=NULL && !accessvfile.ff_name,4 && udata1<vfile.ff_fsize )
158 {
159 udata1=start;
160 udata2=udata3;
161 while(udata1 < vfile.ff_fsize)
162 {
163 if(fseekvp,udata1,SEEK_SET!=0)
164 break;
165 ch=getc(vp);
166 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t' && ch!=20 && ch!=22)
167 {
168 if(ch==dbsign[udata2])
169 {
170 udata2=udata2+1;
171 if(dbsign[udata2]==0)
172 {
173 found=1;
174 break;
175 }
176 }
177 else
178 break;
179 }
180 udata1=udata1+1;
181 }
182
183 if(found==1)
184 {
185 cout<<"\n\n"<<tempo;
186 cout<<"\nFile: "<<vfile.ff_name<<" ";
187 for(udata1=0;1;udata1++)
188 {
189 if(dbsign[udata1]!=20)
190 cout<<dbsign[udata1];
191 else
192 break;
193 }
194 cout<<" Virus found.\n";
195 fflush(vp);
196 fclose(vp);
197 found=0;
198 }
199 else
200 fclose(vp);
201 }
202 else
203 fclose(vp);
204 udata1=findnext(&vfile);
205 }
206
207 if(present[0]==tempo[0])
208 system("cd\\");
209 chdir(present);
210
211 ch=fread(&start,sizeofstart,1,dp);
212 if(ch+1==1)
213 break;
214 }
215 }
216 fclose(dp);
217 udata1=findnext(&dfile);
218 }
219 free(dbsign);
220 }
221
222 void dump(char *dump)
223 {
224 for(count=0;count<udata1;count++)
225 {
226 if( dump[count]>=97 && dump[count]<=122 )
227 dump[count]=dump[count]-32;
228 }
229 }hscan.cpp
1 #include<iostream.h>
2 #include<conio.h>
3 #include<dirent.h>
4 #include<dir.h>
5 #include<process.h>
6 #include<string.h>
7 #include<stdio.h>
8 #include<io.h>
9 #include<dos.h>
10 #include<sys/stat.h>
11
12 FILE *dp,*vp;
13 unsigned int count;
14 struct ffblk dfile;
15 struct ffblk vfile;
16 char base,ch,found=0;
17 char present[MAXPATH];
18 char *sign = (char *) malloc(9);
19 unsigned long int start,udata1,udata2,udata3;
20
21 int next_directory(char *);
22 void scan_directory(char *);
23 void dump(char *);
24
25 void main(int account,char *arg[],char *env[])
26 {
27 if( account==2 && !strcmparg[1]+1,"YVRGRASEWXC" )
28 {
29 DIR *dir;
30 struct dirent *temp;
31
32 base=env[24][12];
33 clrscr();
34
35 getcwd(present,MAXPATH);
36 char drive[]="X:\\";
37 drive[0]=*(arg[1]+0);
38 if (dir = opendirdrive == NULL)
39 {
40 cout<<"\nError : Device not found";
41 free(sign);
42 sleep(2);
43 exit(0);
44 }
45
46 scan_directory(drive);
47 while (temp = readdirdir != NULL)
48 {
49 char *directory = (char *) malloc(3+strlentemp->d_name+1);
50 strcpy(directory,drive);
51 strcat(directory,temp->d_name);
52 next_directory(directory);
53 free(directory);
54 }
55 free(sign);
56 closedir(dir);
57 clrscr();
58 }
59 }
60
61 int next_directory(char *path)
62 {
63 int count=0;
64 DIR *dirtemp;
65 char *hold,*temp;
66 struct dirent *ptemp;
67
68 hold=path;
69 if (dirtemp = opendirpath != NULL)
70 scan_directory(path);
71 else
72 return 0;
73
74 while (ptemp = readdirdirtemp != NULL)
75 {
76 char *directory = (char *) malloc(1+strlenptemp->d_name+1);
77 directory[0]='\\';
78 strcpy(directory+1,ptemp->d_name);
79 if(directory[1]!='\.')
80 {
81
82 count=strlen(hold);
83 temp = (char *) malloc(strlenhold+strlendirectory+1);
84 strcpy(temp,hold);
85 strcat(temp,directory);
86 free(directory);
87 if(opendirtemp!=NULL)
88 next_directory(temp);
89 temp[count]='\0';
90 hold=temp;
91 }
92 else
93 free(directory);
94 }
95 closedir(dirtemp);
96 return 0;
97 }
98
99 void scan_directory(char *tempo)
100 {
101 char *dbsign = (char *) malloc(40+2+400+1);
102 udata1 = findfirst("*.db",&dfile,0x02);
103 while (!udata1)
104 {
105 dp = fopen(dfile.ff_name,"r");
106 fread(sign,8,1,dp);
107 if(!strcmpsign,"LITTLE17")
108 {
109 fread(&start,sizeofstart,1,dp);
110 while(1)
111 {
112 udata1=0;
113 while(1)
114 {
115 ch=fgetc(dp);
116 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t')
117 {
118 if(ch==20)
119 udata2=udata1;
120 if(ch!=22)
121 {
122 dbsign[udata1]=ch;
123 udata1=udata1+1;
124 dbsign[udata1]='\0';
125 continue;
126 }
127 else
128 break;
129 }
130 }
131 udata2=udata2+1;
132 udata3=udata2;
133
134 if(present[0]==tempo[0])
135 chdir(tempo);
136 else
137 {
138 setdisk(tempo[0]-65);
139 chdir(tempo);
140 }
141
142 udata1 = findfirst("*.*",&vfile,0x02);
143 while (!udata1)
144 {
145 found=0;
146 clrscr();
147 cout<<"\nNow scanning:"<<vfile.ff_name;
148 cout<<"\nLocation "<<tempo;
149
150 vp=fopen(vfile.ff_name,"r");
151 if( vp!=NULL && !accessvfile.ff_name,4)
152 {
153 udata1=start;
154 udata2=udata3;
155 while(udata1 < vfile.ff_fsize)
156 {
157 if(fseekvp,udata1,SEEK_SET!=0)
158 break;
159 ch=getc(vp);
160 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t' && ch!=20 && ch!=22)
161 {
162 if(ch==dbsign[udata2])
163 {
164 udata2=udata2+1;
165 if(dbsign[udata2]==0)
166 {
167 cout<<"\a\n\n"<<tempo;
168 cout<<"\nFile: "<<vfile.ff_name<<" ";
169 for(udata1=0;1;udata1++)
170 {
171 if(dbsign[udata1]!=20)
172 cout<<dbsign[udata1];
173 else
174 break;
175 }
176 cout<<" Virus found.\n";
177 fflush(vp);
178 fclose(vp);
179 found=1;
180 break;
181 }
182 }
183 else
184 break;
185 }
186 udata1=udata1+1;
187 }
188
189 if(found==0)
190 {
191 count=0;
192 udata1=0;
193 udata2=udata3;
194 while(udata1<vfile.ff_fsize)
195 {
196 fseek(vp,udata1,SEEK_SET);
197 ch=fgetc(vp);
198 if(ch!=0 && ch!=32 && ch!='\n' && ch!='\t' && ch!=20 && ch!=22)
199 {
200 if(ch!=dbsign[udata2])
201 {
202 if(count>=2)
203 udata1=udata1-count;
204 count=0;
205 udata2=udata3;
206 }
207 else
208 {
209 count=count+1;
210 udata2=udata2+1;
211 if(dbsign[udata2]==0)
212 {
213 cout<<"\a\n\n"<<tempo;
214 cout<<"\nFile: "<<vfile.ff_name<<" ";
215 for(udata1=0;1;udata1++)
216 {
217 if(dbsign[udata1]!=20)
218 cout<<dbsign[udata1];
219 else
220 break;
221 }
222 cout<<" Virus found.\n";
223 fflush(vp);
224 fclose(vp);
225 found=1;
226 break;
227 }
228 }
229
230 }
231 udata1=udata1+1;
232 }
233
234 }
235
236 }
237
238 if(found==0)
239 fclose(vp);
240 else
241 found==0;
242
243 udata1=findnext(&vfile);
244 }
245
246 if(present[0]==tempo[0])
247 system("cd\\");
248 chdir(present);
249
250 ch=fread(&start,sizeofstart,1,dp);
251 if(ch+1==1)
252 break;
253 }
254 }
255 fclose(dp);
256 udata1=findnext(&dfile);
257 }
258 }
259
260 void dump(char *dump)
261 {
262 for(count=0;count<udata1;count++)
263 {
264 if( dump[count]>=97 && dump[count]<=122 )
265 dump[count]=dump[count]-32;
266 }
267 }