exc

#include <stdio.h>
#include <setjmp.h>
#include <stdlib.h>

typedef struct exception {
    jmp_buf buf;
    int code;
} exception;

exception buffer[10];
int stp = 0;

jmp_buf *try(int exception) {
    buffer[stp].code = exception;
    return &buffer[stp++].buf;
}

void endtry() {
    stp--;
}

void throw(int exception) {
    while (stp > 0 && buffer[stp - 1].code != exception) { stp--; }
    stp--;
    if (stp == -1) {
        exit(13);
    }
    longjmp(buffer[stp].buf, buffer[stp].code);
}

int main(int argc, char *argv[]) {
    if (!setjmp(*try(42))) {
        puts("level 1");
        if (!setjmp(*try(1))) {
            puts("level 2");
            throw(42);
            puts("this string is not displayed");
            endtry();
        } else {
            puts("handle exception 1");
        }
        endtry();
    } else {
        puts("handle exception 42");
    }
    return 0;
}