Brainfuck interpreter written in C

[mad1231999]

This is just a Brainfuck interpreter that I made in the programming language C. It's only 36 lines, and still very readable!

Source code:

Code:

#include <stdio.h>
const int MAX_DEPTH = 100, MEM_SIZE = 30000;

int main(int argc, char **argv)
{
    if(argc <= 1) { printf("You have to specify a filename. Usage:\n<executable> <BF filename>\n"); return 0; }
    
    char mem[MEM_SIZE]; // 30,000 is default with Brainfuck
    int lindex[MAX_DEPTH];
    int depth = 0, len = 0, ptr = 0;
    
    FILE *f = fopen(argv[1], "r");
    if(f == 0) { printf("Invalid filename: %s\n", argv[1]); return 0; }
    int curr; while((curr = fgetc(f)) != EOF)  
    {
        switch((char) curr)
        {
            case '+':   ++(mem[ptr]);                       break;
            case '-':   --(mem[ptr]);                       break;
            case '<':   if(ptr > 0) --ptr;                  break;
            case '>':   if(ptr < MEM_SIZE) ++ptr;           break;
            case '.':   putchar(mem[ptr]);                  break;
            case ',':   mem[ptr] = getchar();getchar();     break;
            case '[':   if(mem[ptr] == 0) {
                            int d = 0, i = ftell(f); char c = '\0';
                            while(!feof(f)) { ++i; c = fgetc(f); if(c == '[') { ++d; } else if(c == ']') { if(d == 0) { fseek(f, i, SEEK_SET); break; } else { --d; } } }
                        } else
                            lindex[depth++] = ftell(f);
                        break;
            case ']':   if(depth > 0 && mem[ptr] == 0) {} else { fseek(f, lindex[depth - 1], SEEK_SET); } break;
            default: break;
        } if(feof(f)) break;
    }
    fclose(f);
    printf("\n");
}

or on Github.

How to compile:
On windows, install Mingw, and run this command:

Code:

mingw32-gcc Brainfuck.c -o BF.exe

and run the executabe from the commandline.

On Mac or Linux, run this:

Code:

gcc Brainfuck.c -o BF

and run the executable from the commandline.

Alternatively, you can just install Code::Blocks and compile with that too(should work on all platforms).

[JeremyG]

In my opinion, the number of 'lines' is a bad measurement. You could put everything on 1 line in most programming languages.

[mad1231999]

In my opinion, the number of 'lines' is a bad measurement. You could put everything on 1 line in most programming languages.

Yeah, I know. I just needed to beat Invalid

[mort96]

I just made a BF interpreter one line. Beat that.

Code:

#include <stdio.h>; const int MAX_DEPTH = 100, MEM_SIZE = 30000; int main(int argc, char **argv){ if(argc <= 1) { printf("You have to specify a filename. Usage:\n<executable> <BF filename>\n"); return 0; }; char mem[MEM_SIZE]; int lindex[MAX_DEPTH]; int depth = 0, len = 0, ptr = 0; FILE *f = fopen(argv[1], "r"); if(f == 0) { printf("Invalid filename: %s\n", argv[1]); return 0; }; int curr; while((curr = fgetc(f)) != EOF){ switch((char) curr){ case '+':   ++(mem[ptr]); break; case '-':   --(mem[ptr]); break; case '<':   if(ptr > 0) --ptr; break; case '>':   if(ptr < MEM_SIZE) ++ptr; break; case '.':   putchar(mem[ptr]); break; case ',':   mem[ptr] = getchar();getchar(); break; case '[':   if(mem[ptr] == 0) { int d = 0, i = ftell(f); char c = '\0'; while(!feof(f)) { ++i; c = fgetc(f); if(c == '[') { ++d; } else if(c == ']') { if(d == 0) { fseek(f, i, SEEK_SET); break; } else { --d; } } } } else { lindex[depth++] = ftell(f); break; case ']':   if(depth > 0 && mem[ptr] == 0) {} else { fseek(f, lindex[depth - 1], SEEK_SET); } break; default: break; } if(feof(f)) break; } fclose(f); printf("\n");}

(not tested it, but let's say it works for the sake of argument - simply modified mads' interpreter in notepad during a boring class at school )

[mad1231999]

I just made a BF interpreter one line. Beat that.

Code:

#include <stdio.h>; const int MAX_DEPTH = 100, MEM_SIZE = 30000; int main(int argc, char **argv){ if(argc <= 1) { printf("You have to specify a filename. Usage:\n<executable> <BF filename>\n"); return 0; }; char mem[MEM_SIZE]; int lindex[MAX_DEPTH]; int depth = 0, len = 0, ptr = 0; FILE *f = fopen(argv[1], "r"); if(f == 0) { printf("Invalid filename: %s\n", argv[1]); return 0; }; int curr; while((curr = fgetc(f)) != EOF){ switch((char) curr){ case '+':   ++(mem[ptr]); break; case '-':   --(mem[ptr]); break; case '<':   if(ptr > 0) --ptr; break; case '>':   if(ptr < MEM_SIZE) ++ptr; break; case '.':   putchar(mem[ptr]); break; case ',':   mem[ptr] = getchar();getchar(); break; case '[':   if(mem[ptr] == 0) { int d = 0, i = ftell(f); char c = '\0'; while(!feof(f)) { ++i; c = fgetc(f); if(c == '[') { ++d; } else if(c == ']') { if(d == 0) { fseek(f, i, SEEK_SET); break; } else { --d; } } } } else { lindex[depth++] = ftell(f); break; case ']':   if(depth > 0 && mem[ptr] == 0) {} else { fseek(f, lindex[depth - 1], SEEK_SET); } break; default: break; } if(feof(f)) break; } fclose(f); printf("\n");}

(not tested it, but let's say it works for the sake of argument - simply modified mads' interpreter in notepad during a boring class at school )

You can't have preprocessor stuff and code on the same line, neither can you have 2 preprocessor statements on one line

[redstonewarrior]

Use... use inline assembly for IO then...

[JeremyG]

I know I'm late, but here have this

Code:

s[99],*r=s,*d,c;main(a,b){char*v=1[d=b];for(;c=*v++%93;)for(b=c&2,b=c%7?a&&(c&17
?c&1?(*r+=b-1):(r+=b-1):syscall(4-!b,b,r,1),0):v;b&&c|a**r;v=d)main(!c,&a);d=v;}

[Xeomorpher]

I like my cats warm and fuzzly.

[David]

I like my cats warm and fuzzly.

I like my cats deep fried

[VirtualPineapple]

I like my cats warm and fuzzly.

I like my cats deep fried

Faith in humanity is lost once again.

[Xeomorpher]

My cat would not be happy to read that.

[Malcolmforde]

How to use it?

[VirtualPineapple]

How to compile:
On windows, install Mingw, and run this command:
Code:
mingw32-gcc Brainfuck.c -o BF.exe
and run the executable from the commandline.

Make a new file, input your BF code, save it. Then in the command line do BF (filename)

[Malcolmforde]

How to compile:
On windows, install Mingw, and run this command:
Code:
mingw32-gcc Brainfuck.c -o BF.exe
and run the executable from the commandline.

Make a new file, input your BF code, save it. Then in the command line do BF (filename)

But... what type of file? :o

[VirtualPineapple]

Any file type... do like Testing.bf

[AFtExploision]

tid=69

[VirtualPineapple]

fucking bumpers T_T, leave dead threads dead. Don't practice necrophelia