hexdump.cpp

#include <iostream>
#include <fstream>
#include <sys/stat.h>
#include <unistd.h>

#if defined(WIN32) || defined(_WIN32) || defined(__WIN32) && !defined(__CYGWIN__)
    #include <io.h>
    #include <stdio.h>
    #include <fcntl.h>
#endif

using namespace std;

typedef unsigned char byte;

void dump_stream(istream& reader, int width=16){
    byte b;
    byte c[width+1];
    for(int i=0;i<width+1;i++){c[i]='\x0';}
    int col=0;
    int offset=0;
    printf("        |");
    for(int i=0;i<width;i++){
        printf("%02X ",i);
    }
    printf("\n--------+");
    for(int i=0;i<width;i++){
        printf("---");
    }
    printf("\n");
    printf("%08X|",offset);
    while(!reader.eof()){
        b=reader.get();
        printf("%02X ",b);
        if(b>=32 && b<=127){c[col]=b;}
        else{c[col]='.';}
        col++;
        if(col>width-1){
            offset+=width;
            printf("|%s|\n%08X|",c,offset);
            col=0;
        }
    }
    while(col<width){
        printf("   ");
        c[col]='\x0';
        col++;
    }
    offset+=width;
    printf("|%s|\n%08X|\n",c,offset);
}

bool exists(const char *name){
    struct stat buf;
    if(stat(name,&buf)!=-1){return true;}
    return false;
}

int pow(int x,int y){
    if(y==0){return 1;}
    int r=x;
    for(int i=0;i<y-1;i++){
        r*=x;
    }
    return r;
}

int parseInt(char* text){
    int len=strlen(text);
    int t=0;
    int r=0;
    for(int i=len-1;i>-1;i--){
        r+=((int)text[i]-48)*pow(10,t);
        t++;
    }
    return r;
}

int main(int argc, char *argv[]){
    int opt=0;
    int argn=0;
    int width=16;
    while((opt=getopt(argc, argv, "hw:"))!=-1){
        argn++;
        switch(opt){
            case 'h':
                printf("usage: %s [options] <filename/s>\n",argv[0]);
                printf("If <filename/s> is omitted, stdin is used.\n");
                printf("Options:\n");
                printf("-h     Shows this text.\n");
                printf("-w<N>  Sets the dump's width to N bytes.\n");
                return 0;
            case 'w':
                width=parseInt(optarg);
                break;
        }
    }
    if(argc>=2+argn){
        for(int i=1;i<argc-argn;i++){
            char *fname=argv[argn+i];
            if(!exists(fname)){
                printf("File \"%s\" not found.\n",fname);
                return 1;
            }
            ifstream reader;
            reader.open(fname,ios_base::binary);
            dump_stream(reader,width);
            reader.close();
        }
    }
    else{
        #if defined(WIN32) || defined(_WIN32) || defined(__WIN32) && !defined(__CYGWIN__)
            _setmode(_fileno(stdin), _O_BINARY);
            dump_stream(cin,width);
        #else
            ifstream reader;
            reader.open("/dev/stdin",ios_base::binary);
            dump_stream(reader,width);
            reader.close();
        #endif
    }
    return 0;
}