As everyone is explaining pertaining to leave based on their experience, it is mostly correct. The leave policy depends on the regulations of each factory, company, or establishment. The leave policy may have been formulated according to settlements or agreements, etc. You should verify if your entity is a factory or establishment under the shop act, as mentioned by Mr. Khola. Then, decide based on your state's policy regarding leave in the shop act, if applicable.
Normally, privilege or earned leave is described in any law, not casual leave (C.L.) or sick leave (S.L.), unless the ESI Act is applicable in such companies. This discussion pertains only to S.L.
Regards,
KIRAN KALE