diff options
Diffstat (limited to 'src/include/regex/regguts.h')
| -rw-r--r-- | src/include/regex/regguts.h | 54 |
1 files changed, 39 insertions, 15 deletions
diff --git a/src/include/regex/regguts.h b/src/include/regex/regguts.h index 0cced701dbd..fb6789b560f 100644 --- a/src/include/regex/regguts.h +++ b/src/include/regex/regguts.h @@ -181,34 +181,52 @@ union tree #define tcolor colors.ccolor #define tptr ptrs.pptr -/* internal per-color descriptor structure for the color machinery */ +/* + * Per-color data structure for the compile-time color machinery + * + * If "sub" is not NOSUB then it is the number of the color's current + * subcolor, i.e. we are in process of dividing this color (character + * equivalence class) into two colors. See src/backend/regex/README for + * discussion of subcolors. + * + * Currently-unused colors have the FREECOL bit set and are linked into a + * freelist using their "sub" fields, but only if their color numbers are + * less than colormap.max. Any array entries beyond "max" are just garbage. + */ struct colordesc { uchr nchrs; /* number of chars of this color */ - color sub; /* open subcolor (if any); free chain ptr */ -#define NOSUB COLORLESS - struct arc *arcs; /* color chain */ - int flags; + color sub; /* open subcolor, if any; or free-chain ptr */ +#define NOSUB COLORLESS /* value of "sub" when no open subcolor */ + struct arc *arcs; /* chain of all arcs of this color */ + int flags; /* bit values defined next */ #define FREECOL 01 /* currently free */ #define PSEUDO 02 /* pseudocolor, no real chars */ #define UNUSEDCOLOR(cd) ((cd)->flags&FREECOL) union tree *block; /* block of solid color, if any */ }; -/* the color map itself */ +/* + * The color map itself + * + * Only the "tree" part is used at execution time, and that only via the + * GETCOLOR() macro. Possibly that should be separated from the compile-time + * data. + */ struct colormap { int magic; #define CMMAGIC 0x876 struct vars *v; /* for compile error reporting */ - size_t ncds; /* number of colordescs */ - size_t max; /* highest in use */ + size_t ncds; /* allocated length of colordescs array */ + size_t max; /* highest color number currently in use */ color free; /* beginning of free chain (if non-0) */ - struct colordesc *cd; + struct colordesc *cd; /* pointer to array of colordescs */ #define CDEND(cm) (&(cm)->cd[(cm)->max + 1]) + /* If we need up to NINLINECDS, we store them here to save a malloc */ #define NINLINECDS ((size_t)10) struct colordesc cdspace[NINLINECDS]; - union tree tree[NBYTS]; /* tree top, plus fill blocks */ + union tree tree[NBYTS]; /* tree top, plus lower-level fill blocks */ }; /* optimization magic to do fast chr->color mapping */ @@ -229,19 +247,25 @@ struct colormap /* - * Interface definitions for locale-interface functions in locale.c. + * Interface definitions for locale-interface functions in regc_locale.c. */ -/* Representation of a set of characters. */ +/* + * Representation of a set of characters. chrs[] represents individual + * code points, ranges[] represents ranges in the form min..max inclusive. + * + * Note that in cvecs gotten from newcvec() and intended to be freed by + * freecvec(), both arrays of chrs are after the end of the struct, not + * separately malloc'd; so chrspace and rangespace are effectively immutable. + */ struct cvec { int nchrs; /* number of chrs */ - int chrspace; /* number of chrs possible */ + int chrspace; /* number of chrs allocated in chrs[] */ chr *chrs; /* pointer to vector of chrs */ int nranges; /* number of ranges (chr pairs) */ - int rangespace; /* number of chrs possible */ + int rangespace; /* number of ranges allocated in ranges[] */ chr *ranges; /* pointer to vector of chr pairs */ - /* both batches of chrs are on the end */ }; |