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MTBL_VARINT(3)                                                  MTBL_VARINT(3)

NAME
       mtbl_varint - Variable-width encoding and decoding of 32 and 64 bit
       integers

SYNOPSIS
       #include <mtbl.h>

       unsigned mtbl_varint_length(uint64_t value);

       unsigned mtbl_varint_length_packed(const uint8_t *buf, size_t len_buf);

       size_t mtbl_varint_encode32(uint8_t *ptr, uint32_t value);

       size_t mtbl_varint_encode64(uint8_t *ptr, uint64_t value);

       size_t mtbl_varint_decode32(const uint8_t *ptr, uint32_t *value);

       size_t mtbl_varint_decode64(const uint8_t *ptr, uint64_t *value);

DESCRIPTION
       mtbl_varint_encode32() and mtbl_varint_encode64() write the 32 or 64
       bit quantity, respectively, in the argument value to the buffer in the
       argument dst. The quantity will be written in using a variable-width
       encoding that uses at most 5 bytes for a 32 bit quantity or 10 bytes
       for a 64 bit quantity.

       mtbl_varint_decode32() and mtbl_varint_decode64() read the 32 or 64 bit
       varint quantity, respectively, in the argument ptr. The quantity read
       will be placed in the argument value.

       Bounds checking must be performed by the caller.

RETURN VALUE
       mtbl_varint_encode32() and mtbl_varint_encode64() return the number of
       bytes written to dst.

       mtbl_varint_decode32() and mtbl_varint_decode64() return the number of
       bytes read from ptr.

       mtbl_varint_length() returns the number of bytes that its argument
       value would require in the variable-width encoding.

       mtbl_varint_length_packed() returns the number of bytes consumed by the
       variable-width encoded quantity at its argument data. It will read at
       most len_buf bytes from data. The value 0 is returned if a valid varint
       is not present.

                                  01/31/2014                    MTBL_VARINT(3)