If another resource is available, acquire it and return true. Else return false.

此时的 key 仍然为 InternalKey，也就是 User Key + Sequence Number | Value Type */

Apply all of the edits in *edit to the current state.

* BuildTable 除了 Build New SSTable 之外，还会使用 meta 指针记录下 New SSTable 的元信息， * */

null if options_.paranoid_checks==false

Helper routine: decode the next block entry starting at "p", storing the number of shared key bytes, non_shared key bytes, and the length of the value

Global set by main() and read in TestCloseOnExec. The argv[0] value is stored in a std::vector instead of a std::string because std::string does not

Assume a filename, and not a directory name like "/foo/bar/"

True if the node is not used. Only head nodes might be unused.

Lock or unlock the entire file as specified by |lock|. Returns true when successful, false upon failure. Caller should call ::GetLastError() to determ

Return the current log file number.

Return the name of the old info log file for "dbname".

Print contents of a log file. (*func)() is called on every record.

Return a skewed potentially long string

Save the current state in *v.

Takes ownership of "iter" and will delete it when destroyed, or when Set() is invoked again.

* SomeFileOverlapsRange() 做的事情其实就是判断 New SSTable 和当前 level 是否存在重叠的 Key。 * * disjoint_sorted_files 表示是否互斥，只有在计算 level 0 时该值为 false，其余情况为 true; * fil

A basic file truncation function suitable for this test.

Return the value to associate with the specified key

REQUIRES: External synchronization