diff options
Diffstat (limited to 'src/nvim/memline_defs.h')
| -rw-r--r-- | src/nvim/memline_defs.h | 71 |
1 files changed, 41 insertions, 30 deletions
diff --git a/src/nvim/memline_defs.h b/src/nvim/memline_defs.h index 34a002af5d..edd933b2cd 100644 --- a/src/nvim/memline_defs.h +++ b/src/nvim/memline_defs.h @@ -3,54 +3,65 @@ #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) - */ +/// +/// 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 */ + 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() */ - +// Flags when calling ml_updatechunk() #define ML_CHNK_ADDLINE 1 #define ML_CHNK_DELLINE 2 #define ML_CHNK_UPDLINE 3 -/* - * the memline structure holds all the information about a memline - */ +/// 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 */ + linenr_T ml_line_count; // number of lines in the buffer - memfile_T *ml_mfp; /* pointer to associated memfile */ + 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 */ +#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 */ + 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 */ + 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 */ + 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; |