Communication shim between Wsl and Windows

win2wsl.cpp

#include <cstdio>
#include <cstdlib>
#include <vector>
#include <string>
#include <iostream>
#include <regex>

using namespace std;

string toUnix(char*);
string toWin(char*);

regex reIsFileNameWin  ("^(?:\\.\\.|\\.|([a-zA-Z])\\:)\\\\[^\\<\\>\\:\"/|\\?\\*]+"); 
regex reWinDrive       ("^([a-zA-Z])\\:");
regex reIsFileNameUnix ("^(?:\\.\\.|\\.|/mnt/([a-z]))/[^\\<\\>\\:\"\\\\|\\?\\*]+"); 
regex reUnixMnt        ("^/mnt/([a-z])");

int main(int argc, char **argv)
{
    FILE   *in;
    char   buff  [512];
    string cmd ("C:\\Windows\\System32\\bash.exe");

    for (int i = 1; i < argc; ++i) {
        cmd += ' ' + toUnix(argv[i]);
    }

    cout << cmd << endl;

    if (!(in = popen(cmd.c_str(), "r"))) {
        return 1;
    }
    
    // FIXME: bash.exe apparently can't pipe out to other programs?
    while (fgets(buff, sizeof(buff), in) != NULL) {
        cout << toWin(buff);
    }

    pclose(in);
    return 0;
}

string toUnix(char* in) {
    string s = in;
    cmatch cm;
    if (regex_match(in, cm, reIsFileNameWin)) {
        s = regex_replace(s, reWinDrive, "\\mnt\\$1");
        if (cm.size() >= 2 && cm[1].length() > 0) {
            s[5] = tolower(s[5]);
        }
        replace(s.begin(), s.end(), '\\', '/');
    } 
    return s;
}

string toWin(char* in) {
    string s = in;
    cmatch cm;
    if (regex_match(in, cm, reIsFileNameUnix)) {
        s = regex_replace(s, reUnixMnt, "$1:");
        if (cm.size() >= 2 && cm[1].length() > 0) {
            s[0] = toupper(s[0]);
        }
        replace(s.begin(), s.end(), '/', '\\');
    } 
    return s;
}

Does this actually work?