Encrypts the specified contents of the buffer to an SHA-1 hash. SHA-1 is used for string encryption and other data authentication in programming, and also the popular GitHub source revision control services, it was designed by the United States National Security Agency.
|buffer||integer||the index of the buffer to encrypt the contents of|
|offset||unsigned||offset into the buffer where the contents start, in bytes|
|size||unsigned||size of the contents to encrypt, in bytes|
string: Returns an SHA-1 hash of the specified contents of the buffer.
hash = buffer_sha1(mybuffer, 0, buffer_get_size(buff));