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chunkCountForPlaintext

chunkCountForPlaintext(plaintextLength, chunkSize): number

Defined in: packages/filecoin-encryption-envelope/src/chunk-layout.ts:84

Chunk count an encoder writes into the chunk_count header for a plaintext of the given length. This is deliberately not the inverse of chunkLayout: a plaintext that is an exact multiple of the chunk size can be sealed validly as either k chunks (last one full) or k+1 (last one empty, carrying only its tag), and both decrypt to identical bytes. We always WRITE the k form here, but a decoder must ACCEPT both — so the header this function produces is checked against chunkLayout(ciphertextSize, chunkSize).chunkCount, never against chunkCountForPlaintext run in reverse on the plaintext size.

ParameterType
plaintextLengthnumber
chunkSizenumber

number