C/C++ comment remover

remcomment.c

// Jakub Sebek, Feb 2022, Public Domain
// Please report bugs
#include <stdio.h>
#include <stdbool.h>
#include <assert.h>

int main() {
    
    bool stresc = false, rawstring = false, multil = false;
    char strend = false, rawend[16+2] = ")", *rawdc = NULL;
    for (int l=EOF,c; (c = getchar()) != EOF; 
            !multil && c != EOF && putchar(c), l = c) {

        if (multil) {
            if (c != '*') continue;

            while (l = getchar(), c = getchar(), l == '\\' && c == '\n');
            ungetc(c, stdin); c = l;
            if (c == '/') {
                multil = false;
                c = ' ';
            } else ungetc(c, stdin); // fixes **/

            continue;
        }

        if (rawstring) {
            assert(rawdc - rawend < sizeof(rawend));
            if (*rawdc == '\0' && c == '"') {
                rawstring = false;
                rawdc = NULL;
            } else {
                if (*rawdc++ != c) {
                    rawdc = rawend;
                    if (*rawdc == c) rawdc++; // fixes R"((..))"
                }
                continue;
            }
        } else if (rawdc) {
            assert(rawdc - rawend + 1 < sizeof(rawend));
            if ((*++rawdc = c) != '(') continue;
            *rawdc = '\0';
            rawstring = true;
            rawdc = rawend;
        } else if (!strend && l == 'R' && c == '"')
            rawdc = rawend;

        if ((strend && (c == strend || c == '\n') && !stresc) || 
            (!strend && (c == '\'' || c == '"')))
            strend = strend ? false : c;
        if (strend)
            stresc = (c == '\\' && l != '\\');
        else if (c == '/') {
            int escs = 0;
            while (l = getchar(), c = getchar(), l == '\\' && c == '\n')
                escs++;
            ungetc(c, stdin); c = l;

            if (c == '/') 
                while (c = getchar(), c != EOF && (c != '\n' || l == '\\')) 
                    l = c;
            else if (c == '*') multil = true;    
            else for (putchar('/'); escs--; puts("\\")); 
        }

    }
    assert(!multil); assert(!rawstring); assert(!rawdc); assert(!strend);

    return 0;
}