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Diffstat (limited to 'src/regexp.h')
| -rw-r--r-- | src/regexp.h | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/src/regexp.h b/src/regexp.h new file mode 100644 index 0000000..1ff2e1b --- /dev/null +++ b/src/regexp.h @@ -0,0 +1,191 @@ +/* vi:set ts=8 sts=4 sw=4 noet: + * + * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE + * + * This is NOT the original regular expression code as written by Henry + * Spencer. This code has been modified specifically for use with Vim, and + * should not be used apart from compiling Vim. If you want a good regular + * expression library, get the original code. + * + * NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE + */ + +#ifndef _REGEXP_H +#define _REGEXP_H + +/* + * The number of sub-matches is limited to 10. + * The first one (index 0) is the whole match, referenced with "\0". + * The second one (index 1) is the first sub-match, referenced with "\1". + * This goes up to the tenth (index 9), referenced with "\9". + */ +#define NSUBEXP 10 + +/* + * In the NFA engine: how many braces are allowed. + * TODO(RE): Use dynamic memory allocation instead of static, like here + */ +#define NFA_MAX_BRACES 20 + +/* + * In the NFA engine: how many states are allowed + */ +#define NFA_MAX_STATES 100000 +#define NFA_TOO_EXPENSIVE (-1) + +// Which regexp engine to use? Needed for vim_regcomp(). +// Must match with 'regexpengine'. +#define AUTOMATIC_ENGINE 0 +#define BACKTRACKING_ENGINE 1 +#define NFA_ENGINE 2 + +typedef struct regengine regengine_T; + +/* + * Structure returned by vim_regcomp() to pass on to vim_regexec(). + * This is the general structure. For the actual matcher, two specific + * structures are used. See code below. + */ +typedef struct regprog +{ + regengine_T *engine; + unsigned regflags; + unsigned re_engine; // automatic, backtracking or nfa engine + unsigned re_flags; // second argument for vim_regcomp() + int re_in_use; // prog is being executed +} regprog_T; + +/* + * Structure used by the back track matcher. + * These fields are only to be used in regexp.c! + * See regexp.c for an explanation. + */ +typedef struct +{ + // These four members implement regprog_T + regengine_T *engine; + unsigned regflags; + unsigned re_engine; + unsigned re_flags; + int re_in_use; + + int regstart; + char_u reganch; + char_u *regmust; + int regmlen; +#ifdef FEAT_SYN_HL + char_u reghasz; +#endif + char_u program[1]; // actually longer.. +} bt_regprog_T; + +/* + * Structure representing a NFA state. + * An NFA state may have no outgoing edge, when it is a NFA_MATCH state. + */ +typedef struct nfa_state nfa_state_T; +struct nfa_state +{ + int c; + nfa_state_T *out; + nfa_state_T *out1; + int id; + int lastlist[2]; // 0: normal, 1: recursive + int val; +}; + +/* + * Structure used by the NFA matcher. + */ +typedef struct +{ + // These three members implement regprog_T + regengine_T *engine; + unsigned regflags; + unsigned re_engine; + unsigned re_flags; + int re_in_use; + + nfa_state_T *start; // points into state[] + + int reganch; // pattern starts with ^ + int regstart; // char at start of pattern + char_u *match_text; // plain text to match with + + int has_zend; // pattern contains \ze + int has_backref; // pattern contains \1 .. \9 +#ifdef FEAT_SYN_HL + int reghasz; +#endif + char_u *pattern; + int nsubexp; // number of () + int nstate; + nfa_state_T state[1]; // actually longer.. +} nfa_regprog_T; + +/* + * Structure to be used for single-line matching. + * Sub-match "no" starts at "startp[no]" and ends just before "endp[no]". + * When there is no match, the pointer is NULL. + */ +typedef struct +{ + regprog_T *regprog; + char_u *startp[NSUBEXP]; + char_u *endp[NSUBEXP]; + + colnr_T rm_matchcol; // match start without "\zs" + int rm_ic; +} regmatch_T; + +/* + * Structure to be used for multi-line matching. + * Sub-match "no" starts in line "startpos[no].lnum" column "startpos[no].col" + * and ends in line "endpos[no].lnum" just before column "endpos[no].col". + * The line numbers are relative to the first line, thus startpos[0].lnum is + * always 0. + * When there is no match, the line number is -1. + */ +typedef struct +{ + regprog_T *regprog; + lpos_T startpos[NSUBEXP]; + lpos_T endpos[NSUBEXP]; + + colnr_T rmm_matchcol; // match start without "\zs" + int rmm_ic; + colnr_T rmm_maxcol; // when not zero: maximum column +} regmmatch_T; + +/* + * Structure used to store external references: "\z\(\)" to "\z\1". + * Use a reference count to avoid the need to copy this around. When it goes + * from 1 to zero the matches need to be freed. + */ +typedef struct +{ + short refcnt; + char_u *matches[NSUBEXP]; +} reg_extmatch_T; + +struct regengine +{ + // bt_regcomp or nfa_regcomp + regprog_T *(*regcomp)(char_u*, int); + // bt_regfree or nfa_regfree + void (*regfree)(regprog_T *); + // bt_regexec_nl or nfa_regexec_nl + int (*regexec_nl)(regmatch_T *, char_u *, colnr_T, int); + // bt_regexec_mult or nfa_regexec_mult + long (*regexec_multi)(regmmatch_T *, win_T *, buf_T *, linenr_T, colnr_T, int *); +#ifdef DEBUG + char_u *expr; +#endif +}; + +// Flags used by vim_regsub() and vim_regsub_both() +#define REGSUB_COPY 1 +#define REGSUB_MAGIC 2 +#define REGSUB_BACKSLASH 4 + +#endif // _REGEXP_H |