Converting from String to Enum in C

Question

Is there a convienent way to take a string (input by user) and convert it to an Enumeration value? In this case, the string would be the name of the enumeration value, like

Answer 1

Warning, this is a total hack. You can use dlsym to do a lookup of a variable that is appropriately initialized. For this example to work, you have to compile to allow local symbols to be visible to the dynamic linker. With GCC, the option is -rdynamic.

enum Day {
    SunDay, MonDay, TuesDay, WednesDay, ThursDay, FriDay, SaturDay
};

enum Day Sunday = SunDay,
         Monday = MonDay,
         Tuesday = TuesDay,
         Wednesday = WednesDay,
         Thursday = ThursDay,
         Friday = FriDay,
         Saturday = SaturDay;

int main () {
    const char *daystr = "Thursday";
    void *h = dlopen(0, RTLD_NOW);
    enum Day *day = dlsym(h, daystr);
    if (day) printf("%s = %d\n", daystr, *day);
    else printf("%s not found\n", daystr);
    return 0;
}