Add module API flag for using enum configs as bit flags (#10643)

Enables registration of an enum config that'll let the user pass multiple keywords that
will be combined with `|` as flags into the integer config value.

```
    const char *enum_vals[] = {"none", "one", "two", "three"};
    const int int_vals[] = {0, 1, 2, 4};

    if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 4, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
        return REDISMODULE_ERR;
    }
```
doing:
`config set moduleconfigs.flags "two three"` will result in 6 being passed to`setFlagsConfigCommand`.

1 files changed, 21 insertions, 3 deletions

diff --git a/tests/modules/moduleconfigs.c b/tests/modules/moduleconfigs.c
index af30bda34..0a6380461 100644
--- a/tests/modules/moduleconfigs.c
+++ b/tests/modules/moduleconfigs.c
@@ -6,6 +6,7 @@ long long longval;
 long long memval;
 RedisModuleString *strval = NULL;
 int enumval;
+int flagsval;
 
 /* Series of get and set callbacks for each type of config, these rely on the privdata ptr
  * to point to the config, and they register the configs as such. Note that one could also just
@@ -68,6 +69,20 @@ int setEnumConfigCommand(const char *name, int val, void *privdata, RedisModuleS
     return REDISMODULE_OK;
 }
 
+int getFlagsConfigCommand(const char *name, void *privdata) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(privdata);
+    return flagsval;
+}
+
+int setFlagsConfigCommand(const char *name, int val, void *privdata, RedisModuleString **err) {
+    REDISMODULE_NOT_USED(name);
+    REDISMODULE_NOT_USED(err);
+    REDISMODULE_NOT_USED(privdata);
+    flagsval = val;
+    return REDISMODULE_OK;
+}
+
 int boolApplyFunc(RedisModuleCtx *ctx, void *privdata, RedisModuleString **err) {
     REDISMODULE_NOT_USED(ctx);
     REDISMODULE_NOT_USED(privdata);
@@ -106,10 +121,13 @@ int RedisModule_OnLoad(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
     }
 
     /* On the stack to make sure we're copying them. */
-    const char *enum_vals[3] = {"one", "two", "three"};
-    const int int_vals[3] = {0, 2, 4};
+    const char *enum_vals[] = {"none", "one", "two", "three"};
+    const int int_vals[] = {0, 1, 2, 4};
 
-    if (RedisModule_RegisterEnumConfig(ctx, "enum", 0, REDISMODULE_CONFIG_DEFAULT, enum_vals, int_vals, 3, getEnumConfigCommand, setEnumConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
+    if (RedisModule_RegisterEnumConfig(ctx, "enum", 1, REDISMODULE_CONFIG_DEFAULT, enum_vals, int_vals, 4, getEnumConfigCommand, setEnumConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
+        return REDISMODULE_ERR;
+    }
+    if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 4, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
         return REDISMODULE_ERR;
     }
     /* Memory config here. */