store_name.md

Store the escaped and/or unescaped key name

Problem

Memory Consumption in Elektra is quite high as the key names are long and stored twice in memory.

Constraints

• comparing of keys and thus searching in key sets must be possible with memcmp

Assumptions

• printing the escaped key name is not so much used in typical applications and in tooling doing extra escaping does not matter

Considered Alternatives

• store both
• store both but in one memory block (previous implementation)
• only store escaped name

Decision

Only store the unescaped key name, suitable for comparing/searching/iterating over name, i.e.:

• Remove the escaped name from struct _Key and use it only when necessary.
• Clarify and reduce terminology.
• API Changes:
  • keyNew (const char*, size_t)
  • keyName returns the unescaped name
  • remove keyUnescapedName, keyGetUnescapedNameSize.
  • reverse terminology: with "key name" we will refer to the unescaped (base) name, the escaped name will be explicitly called "escaped key name".
  • escaped name will be outside the core for tooling
  • keyDup(.., int) with options to filter which parts are copied (to allow copy of keys where only the key name is copied)

Rationale

• saves memory
• reduces API (keyUnescapedName*)

Implications

• users should use compare functions, .. instead of keyName
• modifications in keyNew needed

Related Decisions

Notes