neovim/src/nvim/memline_defs.h

71 lines
2.6 KiB
C

#ifndef NVIM_MEMLINE_DEFS_H
#define NVIM_MEMLINE_DEFS_H
#include "nvim/memfile_defs.h"
///
/// When searching for a specific line, we remember what blocks in the tree
/// are the branches leading to that block. This is stored in ml_stack. Each
/// entry is a pointer to info in a block (may be data block or pointer block)
///
typedef struct info_pointer {
blocknr_T ip_bnum; // block number
linenr_T ip_low; // lowest lnum in this block
linenr_T ip_high; // highest lnum in this block
int ip_index; // index for block with current lnum
} infoptr_T; // block/index pair
typedef struct ml_chunksize {
int mlcs_numlines;
long mlcs_totalsize;
} chunksize_T;
// Flags when calling ml_updatechunk()
#define ML_CHNK_ADDLINE 1
#define ML_CHNK_DELLINE 2
#define ML_CHNK_UPDLINE 3
/// memline structure: the contents of a buffer.
/// Essentially a tree with a branch factor of 128.
/// Lines are stored at leaf nodes.
/// Nodes are stored on ml_mfp (memfile_T):
/// pointer_block: internal nodes
/// data_block: leaf nodes
///
/// Memline also has "chunks" of 800 lines that are separate from the 128-tree
/// structure, primarily used to speed up line2byte() and byte2line().
///
/// Motivation: If you have a file that is 10000 lines long, and you insert
/// a line at linenr 1000, you don't want to move 9000 lines in
/// memory. With this structure it is roughly (N * 128) pointer
/// moves, where N is the height (typically 1-3).
///
typedef struct memline {
linenr_T ml_line_count; // number of lines in the buffer
memfile_T *ml_mfp; // pointer to associated memfile
#define ML_EMPTY 1 // empty buffer
#define ML_LINE_DIRTY 2 // cached line was changed and allocated
#define ML_LOCKED_DIRTY 4 // ml_locked was changed
#define ML_LOCKED_POS 8 // ml_locked needs positive block number
int ml_flags;
infoptr_T *ml_stack; // stack of pointer blocks (array of IPTRs)
int ml_stack_top; // current top of ml_stack
int ml_stack_size; // total number of entries in ml_stack
linenr_T ml_line_lnum; // line number of cached line, 0 if not valid
char_u *ml_line_ptr; // pointer to cached line
bhdr_T *ml_locked; // block used by last ml_get
linenr_T ml_locked_low; // first line in ml_locked
linenr_T ml_locked_high; // last line in ml_locked
int ml_locked_lineadd; // number of lines inserted in ml_locked
chunksize_T *ml_chunksize;
int ml_numchunks;
int ml_usedchunks;
} memline_T;
#endif // NVIM_MEMLINE_DEFS_H