Macro for doing a switch on strings - c

Question

Outside of using a hash function, I'd like to write a basic mapping of a key/value lookup of a few movie-credits related items. Does the following macro seem like an acceptable way to do it?
#include <stdio.h>
#include <string.h>
#define TOMAP(input_str, output_buf, from, to) \
if (strcmp(input_str, from) == 0) \
strcpy(output_buf, to)
void map_imdb_position(const char* pos, char output[])
{
TOMAP(pos, output, "Director", "director");
TOMAP(pos, output, "Writer", "scribe");
}
int main(void) {
char position[20];
map_imdb_position("Director", position);
printf("Director->%s\n", position);
}
If not, what might be a better approach to doing a sort of switch statement on a string comparison?

Answer 1

As suggested in the comments a cleaner way to do this would be with a map of credits in a function, for example:
#include <stdio.h>
#include <string.h>
typedef struct map {
char from[20];
char to[20];
} Map;
void map_imdb_position(const char* credit, char output[])
{
static Map credits[] = {
{"Director", "director"},
{"Writer", "scribe"}
};
for (int i=0; i < sizeof(credits)/sizeof(*credits); i++) {
if (strcmp(credit,credits[i].from) == 0) {
strcpy(output, credits[i].to);
break;
}
}
printf("%s --> %s\n", credit, output);
}
int main(void) {
char position[20];
map_imdb_position("Director", position);
map_imdb_position("Writer", position);
}
Working example: https://onlinegdb.com/Sk_t76aQ_

Answer 2

Side note: I was working on this solution but Carl already came up with a similar one.
But, I prefer to use the ptr->field syntax and to have an end-of-table sentinel at the end (vs. the sizeof construct to get the count).
And, I think designated initializers when constructing the table make things more readable [especially if more fields need to be added to the struct].
So, here's my version:
#include <stdio.h>
#include <string.h>
typedef struct {
const char *from;
const char *to;
} mapimdb_t;
mapimdb_t mapimdb[] = {
{ .from = "Director", .to = "director" },
{ .from = "Writer", .to = "scribe" },
// ...
{ .from = NULL }
};
void
map_imdb_position(const char *pos, char *output)
{
for (const mapimdb_t *map = mapimdb; map->from != NULL; ++map) {
if (strcmp(pos,map->from) == 0) {
strcpy(output,map->to);
break;
}
}
}
void
dotest(const char *from,char *out)
{
map_imdb_position(from,out);
printf("dotest: %s->%s\n",from,out);
}
int
main(void)
{
char position[20];
dotest("Director", position);
dotest("Writer", position);
}

Answer 3

X macros can be used:
#include <stdio.h>
#include <string.h>
#define STR_LIST \
X("Director", "director") \
X("Writer", "scribe")
void map_imdb_position(const char* pos, char output[])
{
#define X(from, to) \
if (strcmp(pos, from) == 0) \
{ strcpy(output, to); return; } // "return" was missing?
STR_LIST
#undef X
}
int main(void) {
char position[20];
map_imdb_position("Director", position);
printf("Director->%s\n", position);
}