--- /dev/null
+/*
+ * lexical analyzer
+ * This file is #included by regcomp.c.
+ *
+ * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
+ *
+ * Development of this software was funded, in part, by Cray Research Inc.,
+ * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
+ * Corporation, none of whom are responsible for the results. The author
+ * thanks all of them.
+ *
+ * Redistribution and use in source and binary forms -- with or without
+ * modification -- are permitted for any purpose, provided that
+ * redistributions in source form retain this entire copyright notice and
+ * indicate the origin and nature of any modifications.
+ *
+ * I'd appreciate being given credit for this package in the documentation
+ * of software which uses it, but that is not a requirement.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/* scanning macros (know about v) */
+#define ATEOS() (v->now >= v->stop)
+#define HAVE(n) (v->stop - v->now >= (n))
+#define NEXT1(c) (!ATEOS() && *v->now == CHR(c))
+#define NEXT2(a,b) (HAVE(2) && *v->now == CHR(a) && *(v->now+1) == CHR(b))
+#define NEXT3(a,b,c) (HAVE(3) && *v->now == CHR(a) && \
+ *(v->now+1) == CHR(b) && \
+ *(v->now+2) == CHR(c))
+#define SET(c) (v->nexttype = (c))
+#define SETV(c, n) (v->nexttype = (c), v->nextvalue = (n))
+#define RET(c) return (SET(c), 1)
+#define RETV(c, n) return (SETV(c, n), 1)
+#define FAILW(e) return (ERR(e), 0) /* ERR does SET(EOS) */
+#define LASTTYPE(t) (v->lasttype == (t))
+
+/* lexical contexts */
+#define L_ERE 1 /* mainline ERE/ARE */
+#define L_BRE 2 /* mainline BRE */
+#define L_Q 3 /* REG_QUOTE */
+#define L_EBND 4 /* ERE/ARE bound */
+#define L_BBND 5 /* BRE bound */
+#define L_BRACK 6 /* brackets */
+#define L_CEL 7 /* collating element */
+#define L_ECL 8 /* equivalence class */
+#define L_CCL 9 /* character class */
+#define INTOCON(c) (v->lexcon = (c))
+#define INCON(con) (v->lexcon == (con))
+
+/* construct pointer past end of chr array */
+#define ENDOF(array) ((array) + sizeof(array)/sizeof(chr))
+
+/*
+ - lexstart - set up lexical stuff, scan leading options
+ ^ static VOID lexstart(struct vars *);
+ */
+static VOID
+lexstart(v)
+struct vars *v;
+{
+ prefixes(v); /* may turn on new type bits etc. */
+ NOERR();
+
+ if (v->cflags®_QUOTE) {
+ assert(!(v->cflags&(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE)));
+ INTOCON(L_Q);
+ } else if (v->cflags®_EXTENDED) {
+ assert(!(v->cflags®_QUOTE));
+ INTOCON(L_ERE);
+ } else {
+ assert(!(v->cflags&(REG_QUOTE|REG_ADVF)));
+ INTOCON(L_BRE);
+ }
+
+ v->nexttype = EMPTY; /* remember we were at the start */
+ next(v); /* set up the first token */
+}
+
+/*
+ - prefixes - implement various special prefixes
+ ^ static VOID prefixes(struct vars *);
+ */
+static VOID
+prefixes(v)
+struct vars *v;
+{
+ /* literal string doesn't get any of this stuff */
+ if (v->cflags®_QUOTE)
+ return;
+
+ /* initial "***" gets special things */
+ if (HAVE(4) && NEXT3('*', '*', '*'))
+ switch (*(v->now + 3)) {
+ case CHR('?'): /* "***?" error, msg shows version */
+ ERR(REG_BADPAT);
+ return; /* proceed no further */
+ break;
+ case CHR('='): /* "***=" shifts to literal string */
+ NOTE(REG_UNONPOSIX);
+ v->cflags |= REG_QUOTE;
+ v->cflags &= ~(REG_ADVANCED|REG_EXPANDED|REG_NEWLINE);
+ v->now += 4;
+ return; /* and there can be no more prefixes */
+ break;
+ case CHR(':'): /* "***:" shifts to AREs */
+ NOTE(REG_UNONPOSIX);
+ v->cflags |= REG_ADVANCED;
+ v->now += 4;
+ break;
+ default: /* otherwise *** is just an error */
+ ERR(REG_BADRPT);
+ return;
+ break;
+ }
+
+ /* BREs and EREs don't get embedded options */
+ if ((v->cflags®_ADVANCED) != REG_ADVANCED)
+ return;
+
+ /* embedded options (AREs only) */
+ if (HAVE(3) && NEXT2('(', '?') && iscalpha(*(v->now + 2))) {
+ NOTE(REG_UNONPOSIX);
+ v->now += 2;
+ for (; !ATEOS() && iscalpha(*v->now); v->now++)
+ switch (*v->now) {
+ case CHR('b'): /* BREs (but why???) */
+ v->cflags &= ~(REG_ADVANCED|REG_QUOTE);
+ break;
+ case CHR('c'): /* case sensitive */
+ v->cflags &= ~REG_ICASE;
+ break;
+ case CHR('e'): /* plain EREs */
+ v->cflags |= REG_EXTENDED;
+ v->cflags &= ~(REG_ADVF|REG_QUOTE);
+ break;
+ case CHR('i'): /* case insensitive */
+ v->cflags |= REG_ICASE;
+ break;
+ case CHR('m'): /* Perloid synonym for n */
+ case CHR('n'): /* \n affects ^ $ . [^ */
+ v->cflags |= REG_NEWLINE;
+ break;
+ case CHR('p'): /* ~Perl, \n affects . [^ */
+ v->cflags |= REG_NLSTOP;
+ v->cflags &= ~REG_NLANCH;
+ break;
+ case CHR('q'): /* literal string */
+ v->cflags |= REG_QUOTE;
+ v->cflags &= ~REG_ADVANCED;
+ break;
+ case CHR('s'): /* single line, \n ordinary */
+ v->cflags &= ~REG_NEWLINE;
+ break;
+ case CHR('t'): /* tight syntax */
+ v->cflags &= ~REG_EXPANDED;
+ break;
+ case CHR('w'): /* weird, \n affects ^ $ only */
+ v->cflags &= ~REG_NLSTOP;
+ v->cflags |= REG_NLANCH;
+ break;
+ case CHR('x'): /* expanded syntax */
+ v->cflags |= REG_EXPANDED;
+ break;
+ default:
+ ERR(REG_BADOPT);
+ return;
+ }
+ if (!NEXT1(')')) {
+ ERR(REG_BADOPT);
+ return;
+ }
+ v->now++;
+ if (v->cflags®_QUOTE)
+ v->cflags &= ~(REG_EXPANDED|REG_NEWLINE);
+ }
+}
+
+/*
+ - lexnest - "call a subroutine", interpolating string at the lexical level
+ * Note, this is not a very general facility. There are a number of
+ * implicit assumptions about what sorts of strings can be subroutines.
+ ^ static VOID lexnest(struct vars *, chr *, chr *);
+ */
+static VOID
+lexnest(v, beginp, endp)
+struct vars *v;
+chr *beginp; /* start of interpolation */
+chr *endp; /* one past end of interpolation */
+{
+ assert(v->savenow == NULL); /* only one level of nesting */
+ v->savenow = v->now;
+ v->savestop = v->stop;
+ v->now = beginp;
+ v->stop = endp;
+}
+
+/*
+ * string constants to interpolate as expansions of things like \d
+ */
+static chr backd[] = { /* \d */
+ CHR('['), CHR('['), CHR(':'),
+ CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
+ CHR(':'), CHR(']'), CHR(']')
+};
+static chr backD[] = { /* \D */
+ CHR('['), CHR('^'), CHR('['), CHR(':'),
+ CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
+ CHR(':'), CHR(']'), CHR(']')
+};
+static chr brbackd[] = { /* \d within brackets */
+ CHR('['), CHR(':'),
+ CHR('d'), CHR('i'), CHR('g'), CHR('i'), CHR('t'),
+ CHR(':'), CHR(']')
+};
+static chr backs[] = { /* \s */
+ CHR('['), CHR('['), CHR(':'),
+ CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
+ CHR(':'), CHR(']'), CHR(']')
+};
+static chr backS[] = { /* \S */
+ CHR('['), CHR('^'), CHR('['), CHR(':'),
+ CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
+ CHR(':'), CHR(']'), CHR(']')
+};
+static chr brbacks[] = { /* \s within brackets */
+ CHR('['), CHR(':'),
+ CHR('s'), CHR('p'), CHR('a'), CHR('c'), CHR('e'),
+ CHR(':'), CHR(']')
+};
+static chr backw[] = { /* \w */
+ CHR('['), CHR('['), CHR(':'),
+ CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
+ CHR(':'), CHR(']'), CHR('_'), CHR(']')
+};
+static chr backW[] = { /* \W */
+ CHR('['), CHR('^'), CHR('['), CHR(':'),
+ CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
+ CHR(':'), CHR(']'), CHR('_'), CHR(']')
+};
+static chr brbackw[] = { /* \w within brackets */
+ CHR('['), CHR(':'),
+ CHR('a'), CHR('l'), CHR('n'), CHR('u'), CHR('m'),
+ CHR(':'), CHR(']'), CHR('_')
+};
+
+/*
+ - lexword - interpolate a bracket expression for word characters
+ * Possibly ought to inquire whether there is a "word" character class.
+ ^ static VOID lexword(struct vars *);
+ */
+static VOID
+lexword(v)
+struct vars *v;
+{
+ lexnest(v, backw, ENDOF(backw));
+}
+
+/*
+ - next - get next token
+ ^ static int next(struct vars *);
+ */
+static int /* 1 normal, 0 failure */
+next(v)
+struct vars *v;
+{
+ chr c;
+
+ /* errors yield an infinite sequence of failures */
+ if (ISERR())
+ return 0; /* the error has set nexttype to EOS */
+
+ /* remember flavor of last token */
+ v->lasttype = v->nexttype;
+
+ /* REG_BOSONLY */
+ if (v->nexttype == EMPTY && (v->cflags®_BOSONLY)) {
+ /* at start of a REG_BOSONLY RE */
+ RETV(SBEGIN, 0); /* same as \A */
+ }
+
+ /* if we're nested and we've hit end, return to outer level */
+ if (v->savenow != NULL && ATEOS()) {
+ v->now = v->savenow;
+ v->stop = v->savestop;
+ v->savenow = v->savestop = NULL;
+ }
+
+ /* skip white space etc. if appropriate (not in literal or []) */
+ if (v->cflags®_EXPANDED)
+ switch (v->lexcon) {
+ case L_ERE:
+ case L_BRE:
+ case L_EBND:
+ case L_BBND:
+ skip(v);
+ break;
+ }
+
+ /* handle EOS, depending on context */
+ if (ATEOS()) {
+ switch (v->lexcon) {
+ case L_ERE:
+ case L_BRE:
+ case L_Q:
+ RET(EOS);
+ break;
+ case L_EBND:
+ case L_BBND:
+ FAILW(REG_EBRACE);
+ break;
+ case L_BRACK:
+ case L_CEL:
+ case L_ECL:
+ case L_CCL:
+ FAILW(REG_EBRACK);
+ break;
+ }
+ assert(NOTREACHED);
+ }
+
+ /* okay, time to actually get a character */
+ c = *v->now++;
+
+ /* deal with the easy contexts, punt EREs to code below */
+ switch (v->lexcon) {
+ case L_BRE: /* punt BREs to separate function */
+ return brenext(v, c);
+ break;
+ case L_ERE: /* see below */
+ break;
+ case L_Q: /* literal strings are easy */
+ RETV(PLAIN, c);
+ break;
+ case L_BBND: /* bounds are fairly simple */
+ case L_EBND:
+ switch (c) {
+ case CHR('0'): case CHR('1'): case CHR('2'): case CHR('3'):
+ case CHR('4'): case CHR('5'): case CHR('6'): case CHR('7'):
+ case CHR('8'): case CHR('9'):
+ RETV(DIGIT, (chr)DIGITVAL(c));
+ break;
+ case CHR(','):
+ RET(',');
+ break;
+ case CHR('}'): /* ERE bound ends with } */
+ if (INCON(L_EBND)) {
+ INTOCON(L_ERE);
+ if ((v->cflags®_ADVF) && NEXT1('?')) {
+ v->now++;
+ NOTE(REG_UNONPOSIX);
+ RETV('}', 0);
+ }
+ RETV('}', 1);
+ } else
+ FAILW(REG_BADBR);
+ break;
+ case CHR('\\'): /* BRE bound ends with \} */
+ if (INCON(L_BBND) && NEXT1('}')) {
+ v->now++;
+ INTOCON(L_BRE);
+ RET('}');
+ } else
+ FAILW(REG_BADBR);
+ break;
+ default:
+ FAILW(REG_BADBR);
+ break;
+ }
+ assert(NOTREACHED);
+ break;
+ case L_BRACK: /* brackets are not too hard */
+ switch (c) {
+ case CHR(']'):
+ if (LASTTYPE('['))
+ RETV(PLAIN, c);
+ else {
+ INTOCON((v->cflags®_EXTENDED) ?
+ L_ERE : L_BRE);
+ RET(']');
+ }
+ break;
+ case CHR('\\'):
+ NOTE(REG_UBBS);
+ if (!(v->cflags®_ADVF))
+ RETV(PLAIN, c);
+ NOTE(REG_UNONPOSIX);
+ if (ATEOS())
+ FAILW(REG_EESCAPE);
+ (DISCARD)lexescape(v);
+ switch (v->nexttype) { /* not all escapes okay here */
+ case PLAIN:
+ return 1;
+ break;
+ case CCLASS:
+ switch (v->nextvalue) {
+ case 'd':
+ lexnest(v, brbackd, ENDOF(brbackd));
+ break;
+ case 's':
+ lexnest(v, brbacks, ENDOF(brbacks));
+ break;
+ case 'w':
+ lexnest(v, brbackw, ENDOF(brbackw));
+ break;
+ default:
+ FAILW(REG_EESCAPE);
+ break;
+ }
+ /* lexnest done, back up and try again */
+ v->nexttype = v->lasttype;
+ return next(v);
+ break;
+ }
+ /* not one of the acceptable escapes */
+ FAILW(REG_EESCAPE);
+ break;
+ case CHR('-'):
+ if (LASTTYPE('[') || NEXT1(']'))
+ RETV(PLAIN, c);
+ else
+ RETV(RANGE, c);
+ break;
+ case CHR('['):
+ if (ATEOS())
+ FAILW(REG_EBRACK);
+ switch (*v->now++) {
+ case CHR('.'):
+ INTOCON(L_CEL);
+ /* might or might not be locale-specific */
+ RET(COLLEL);
+ break;
+ case CHR('='):
+ INTOCON(L_ECL);
+ NOTE(REG_ULOCALE);
+ RET(ECLASS);
+ break;
+ case CHR(':'):
+ INTOCON(L_CCL);
+ NOTE(REG_ULOCALE);
+ RET(CCLASS);
+ break;
+ default: /* oops */
+ v->now--;
+ RETV(PLAIN, c);
+ break;
+ }
+ assert(NOTREACHED);
+ break;
+ default:
+ RETV(PLAIN, c);
+ break;
+ }
+ assert(NOTREACHED);
+ break;
+ case L_CEL: /* collating elements are easy */
+ if (c == CHR('.') && NEXT1(']')) {
+ v->now++;
+ INTOCON(L_BRACK);
+ RETV(END, '.');
+ } else
+ RETV(PLAIN, c);
+ break;
+ case L_ECL: /* ditto equivalence classes */
+ if (c == CHR('=') && NEXT1(']')) {
+ v->now++;
+ INTOCON(L_BRACK);
+ RETV(END, '=');
+ } else
+ RETV(PLAIN, c);
+ break;
+ case L_CCL: /* ditto character classes */
+ if (c == CHR(':') && NEXT1(']')) {
+ v->now++;
+ INTOCON(L_BRACK);
+ RETV(END, ':');
+ } else
+ RETV(PLAIN, c);
+ break;
+ default:
+ assert(NOTREACHED);
+ break;
+ }
+
+ /* that got rid of everything except EREs and AREs */
+ assert(INCON(L_ERE));
+
+ /* deal with EREs and AREs, except for backslashes */
+ switch (c) {
+ case CHR('|'):
+ RET('|');
+ break;
+ case CHR('*'):
+ if ((v->cflags®_ADVF) && NEXT1('?')) {
+ v->now++;
+ NOTE(REG_UNONPOSIX);
+ RETV('*', 0);
+ }
+ RETV('*', 1);
+ break;
+ case CHR('+'):
+ if ((v->cflags®_ADVF) && NEXT1('?')) {
+ v->now++;
+ NOTE(REG_UNONPOSIX);
+ RETV('+', 0);
+ }
+ RETV('+', 1);
+ break;
+ case CHR('?'):
+ if ((v->cflags®_ADVF) && NEXT1('?')) {
+ v->now++;
+ NOTE(REG_UNONPOSIX);
+ RETV('?', 0);
+ }
+ RETV('?', 1);
+ break;
+ case CHR('{'): /* bounds start or plain character */
+ if (v->cflags®_EXPANDED)
+ skip(v);
+ if (ATEOS() || !iscdigit(*v->now)) {
+ NOTE(REG_UBRACES);
+ NOTE(REG_UUNSPEC);
+ RETV(PLAIN, c);
+ } else {
+ NOTE(REG_UBOUNDS);
+ INTOCON(L_EBND);
+ RET('{');
+ }
+ assert(NOTREACHED);
+ break;
+ case CHR('('): /* parenthesis, or advanced extension */
+ if ((v->cflags®_ADVF) && NEXT1('?')) {
+ NOTE(REG_UNONPOSIX);
+ v->now++;
+ switch (*v->now++) {
+ case CHR(':'): /* non-capturing paren */
+ RETV('(', 0);
+ break;
+ case CHR('#'): /* comment */
+ while (!ATEOS() && *v->now != CHR(')'))
+ v->now++;
+ if (!ATEOS())
+ v->now++;
+ assert(v->nexttype == v->lasttype);
+ return next(v);
+ break;
+ case CHR('='): /* positive lookahead */
+ NOTE(REG_ULOOKAHEAD);
+ RETV(LACON, 1);
+ break;
+ case CHR('!'): /* negative lookahead */
+ NOTE(REG_ULOOKAHEAD);
+ RETV(LACON, 0);
+ break;
+ default:
+ FAILW(REG_BADRPT);
+ break;
+ }
+ assert(NOTREACHED);
+ }
+ if (v->cflags®_NOSUB)
+ RETV('(', 0); /* all parens non-capturing */
+ else
+ RETV('(', 1);
+ break;
+ case CHR(')'):
+ if (LASTTYPE('(')) {
+ NOTE(REG_UUNSPEC);
+ }
+ RETV(')', c);
+ break;
+ case CHR('['): /* easy except for [[:<:]] and [[:>:]] */
+ if (HAVE(6) && *(v->now+0) == CHR('[') &&
+ *(v->now+1) == CHR(':') &&
+ (*(v->now+2) == CHR('<') ||
+ *(v->now+2) == CHR('>')) &&
+ *(v->now+3) == CHR(':') &&
+ *(v->now+4) == CHR(']') &&
+ *(v->now+5) == CHR(']')) {
+ c = *(v->now+2);
+ v->now += 6;
+ NOTE(REG_UNONPOSIX);
+ RET((c == CHR('<')) ? '<' : '>');
+ }
+ INTOCON(L_BRACK);
+ if (NEXT1('^')) {
+ v->now++;
+ RETV('[', 0);
+ }
+ RETV('[', 1);
+ break;
+ case CHR('.'):
+ RET('.');
+ break;
+ case CHR('^'):
+ RET('^');
+ break;
+ case CHR('$'):
+ RET('$');
+ break;
+ case CHR('\\'): /* mostly punt backslashes to code below */
+ if (ATEOS())
+ FAILW(REG_EESCAPE);
+ break;
+ default: /* ordinary character */
+ RETV(PLAIN, c);
+ break;
+ }
+
+ /* ERE/ARE backslash handling; backslash already eaten */
+ assert(!ATEOS());
+ if (!(v->cflags®_ADVF)) { /* only AREs have non-trivial escapes */
+ if (iscalnum(*v->now)) {
+ NOTE(REG_UBSALNUM);
+ NOTE(REG_UUNSPEC);
+ }
+ RETV(PLAIN, *v->now++);
+ }
+ (DISCARD)lexescape(v);
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ if (v->nexttype == CCLASS) { /* fudge at lexical level */
+ switch (v->nextvalue) {
+ case 'd': lexnest(v, backd, ENDOF(backd)); break;
+ case 'D': lexnest(v, backD, ENDOF(backD)); break;
+ case 's': lexnest(v, backs, ENDOF(backs)); break;
+ case 'S': lexnest(v, backS, ENDOF(backS)); break;
+ case 'w': lexnest(v, backw, ENDOF(backw)); break;
+ case 'W': lexnest(v, backW, ENDOF(backW)); break;
+ default:
+ assert(NOTREACHED);
+ FAILW(REG_ASSERT);
+ break;
+ }
+ /* lexnest done, back up and try again */
+ v->nexttype = v->lasttype;
+ return next(v);
+ }
+ /* otherwise, lexescape has already done the work */
+ return !ISERR();
+}
+
+/*
+ - lexescape - parse an ARE backslash escape (backslash already eaten)
+ * Note slightly nonstandard use of the CCLASS type code.
+ ^ static int lexescape(struct vars *);
+ */
+static int /* not actually used, but convenient for RETV */
+lexescape(v)
+struct vars *v;
+{
+ chr c;
+ static chr alert[] = {
+ CHR('a'), CHR('l'), CHR('e'), CHR('r'), CHR('t')
+ };
+ static chr esc[] = {
+ CHR('E'), CHR('S'), CHR('C')
+ };
+ chr *save;
+
+ assert(v->cflags®_ADVF);
+
+ assert(!ATEOS());
+ c = *v->now++;
+ if (!iscalnum(c))
+ RETV(PLAIN, c);
+
+ NOTE(REG_UNONPOSIX);
+ switch (c) {
+ case CHR('a'):
+ RETV(PLAIN, chrnamed(v, alert, ENDOF(alert), CHR('\007')));
+ break;
+ case CHR('A'):
+ RETV(SBEGIN, 0);
+ break;
+ case CHR('b'):
+ RETV(PLAIN, CHR('\b'));
+ break;
+ case CHR('B'):
+ RETV(PLAIN, CHR('\\'));
+ break;
+ case CHR('c'):
+ NOTE(REG_UUNPORT);
+ if (ATEOS())
+ FAILW(REG_EESCAPE);
+ RETV(PLAIN, (chr)(*v->now++ & 037));
+ break;
+ case CHR('d'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 'd');
+ break;
+ case CHR('D'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 'D');
+ break;
+ case CHR('e'):
+ NOTE(REG_UUNPORT);
+ RETV(PLAIN, chrnamed(v, esc, ENDOF(esc), CHR('\033')));
+ break;
+ case CHR('f'):
+ RETV(PLAIN, CHR('\f'));
+ break;
+ case CHR('m'):
+ RET('<');
+ break;
+ case CHR('M'):
+ RET('>');
+ break;
+ case CHR('n'):
+ RETV(PLAIN, CHR('\n'));
+ break;
+ case CHR('r'):
+ RETV(PLAIN, CHR('\r'));
+ break;
+ case CHR('s'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 's');
+ break;
+ case CHR('S'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 'S');
+ break;
+ case CHR('t'):
+ RETV(PLAIN, CHR('\t'));
+ break;
+ case CHR('u'):
+ c = lexdigits(v, 16, 4, 4);
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ RETV(PLAIN, c);
+ break;
+ case CHR('U'):
+ c = lexdigits(v, 16, 8, 8);
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ RETV(PLAIN, c);
+ break;
+ case CHR('v'):
+ RETV(PLAIN, CHR('\v'));
+ break;
+ case CHR('w'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 'w');
+ break;
+ case CHR('W'):
+ NOTE(REG_ULOCALE);
+ RETV(CCLASS, 'W');
+ break;
+ case CHR('x'):
+ NOTE(REG_UUNPORT);
+ c = lexdigits(v, 16, 1, 255); /* REs >255 long outside spec */
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ RETV(PLAIN, c);
+ break;
+ case CHR('y'):
+ NOTE(REG_ULOCALE);
+ RETV(WBDRY, 0);
+ break;
+ case CHR('Y'):
+ NOTE(REG_ULOCALE);
+ RETV(NWBDRY, 0);
+ break;
+ case CHR('Z'):
+ RETV(SEND, 0);
+ break;
+ case CHR('1'): case CHR('2'): case CHR('3'): case CHR('4'):
+ case CHR('5'): case CHR('6'): case CHR('7'): case CHR('8'):
+ case CHR('9'):
+ save = v->now;
+ v->now--; /* put first digit back */
+ c = lexdigits(v, 10, 1, 255); /* REs >255 long outside spec */
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ /* ugly heuristic (first test is "exactly 1 digit?") */
+ if (v->now - save == 0 || (int)c <= v->nsubexp) {
+ NOTE(REG_UBACKREF);
+ RETV(BACKREF, (chr)c);
+ }
+ /* oops, doesn't look like it's a backref after all... */
+ v->now = save;
+ /* and fall through into octal number */
+ case CHR('0'):
+ NOTE(REG_UUNPORT);
+ v->now--; /* put first digit back */
+ c = lexdigits(v, 8, 1, 3);
+ if (ISERR())
+ FAILW(REG_EESCAPE);
+ RETV(PLAIN, c);
+ break;
+ default:
+ assert(iscalpha(c));
+ FAILW(REG_EESCAPE); /* unknown alphabetic escape */
+ break;
+ }
+ assert(NOTREACHED);
+}
+
+/*
+ - lexdigits - slurp up digits and return chr value
+ ^ static chr lexdigits(struct vars *, int, int, int);
+ */
+static chr /* chr value; errors signalled via ERR */
+lexdigits(v, base, minlen, maxlen)
+struct vars *v;
+int base;
+int minlen;
+int maxlen;
+{
+ uchr n; /* unsigned to avoid overflow misbehavior */
+ int len;
+ chr c;
+ int d;
+ CONST uchr ub = (uchr) base;
+
+ n = 0;
+ for (len = 0; len < maxlen && !ATEOS(); len++) {
+ c = *v->now++;
+ switch (c) {
+ case CHR('0'): case CHR('1'): case CHR('2'): case CHR('3'):
+ case CHR('4'): case CHR('5'): case CHR('6'): case CHR('7'):
+ case CHR('8'): case CHR('9'):
+ d = DIGITVAL(c);
+ break;
+ case CHR('a'): case CHR('A'): d = 10; break;
+ case CHR('b'): case CHR('B'): d = 11; break;
+ case CHR('c'): case CHR('C'): d = 12; break;
+ case CHR('d'): case CHR('D'): d = 13; break;
+ case CHR('e'): case CHR('E'): d = 14; break;
+ case CHR('f'): case CHR('F'): d = 15; break;
+ default:
+ v->now--; /* oops, not a digit at all */
+ d = -1;
+ break;
+ }
+
+ if (d >= base) { /* not a plausible digit */
+ v->now--;
+ d = -1;
+ }
+ if (d < 0)
+ break; /* NOTE BREAK OUT */
+ n = n*ub + (uchr)d;
+ }
+ if (len < minlen)
+ ERR(REG_EESCAPE);
+
+ return (chr)n;
+}
+
+/*
+ - brenext - get next BRE token
+ * This is much like EREs except for all the stupid backslashes and the
+ * context-dependency of some things.
+ ^ static int brenext(struct vars *, pchr);
+ */
+static int /* 1 normal, 0 failure */
+brenext(v, pc)
+struct vars *v;
+pchr pc;
+{
+ chr c = (chr)pc;
+
+ switch (c) {
+ case CHR('*'):
+ if (LASTTYPE(EMPTY) || LASTTYPE('(') || LASTTYPE('^'))
+ RETV(PLAIN, c);
+ RET('*');
+ break;
+ case CHR('['):
+ if (HAVE(6) && *(v->now+0) == CHR('[') &&
+ *(v->now+1) == CHR(':') &&
+ (*(v->now+2) == CHR('<') ||
+ *(v->now+2) == CHR('>')) &&
+ *(v->now+3) == CHR(':') &&
+ *(v->now+4) == CHR(']') &&
+ *(v->now+5) == CHR(']')) {
+ c = *(v->now+2);
+ v->now += 6;
+ NOTE(REG_UNONPOSIX);
+ RET((c == CHR('<')) ? '<' : '>');
+ }
+ INTOCON(L_BRACK);
+ if (NEXT1('^')) {
+ v->now++;
+ RETV('[', 0);
+ }
+ RETV('[', 1);
+ break;
+ case CHR('.'):
+ RET('.');
+ break;
+ case CHR('^'):
+ if (LASTTYPE(EMPTY))
+ RET('^');
+ if (LASTTYPE('(')) {
+ NOTE(REG_UUNSPEC);
+ RET('^');
+ }
+ RETV(PLAIN, c);
+ break;
+ case CHR('$'):
+ if (v->cflags®_EXPANDED)
+ skip(v);
+ if (ATEOS())
+ RET('$');
+ if (NEXT2('\\', ')')) {
+ NOTE(REG_UUNSPEC);
+ RET('$');
+ }
+ RETV(PLAIN, c);
+ break;
+ case CHR('\\'):
+ break; /* see below */
+ default:
+ RETV(PLAIN, c);
+ break;
+ }
+
+ assert(c == CHR('\\'));
+
+ if (ATEOS())
+ FAILW(REG_EESCAPE);
+
+ c = *v->now++;
+ switch (c) {
+ case CHR('{'):
+ INTOCON(L_BBND);
+ NOTE(REG_UBOUNDS);
+ RET('{');
+ break;
+ case CHR('('):
+ RETV('(', 1);
+ break;
+ case CHR(')'):
+ RETV(')', c);
+ break;
+ case CHR('<'):
+ NOTE(REG_UNONPOSIX);
+ RET('<');
+ break;
+ case CHR('>'):
+ NOTE(REG_UNONPOSIX);
+ RET('>');
+ break;
+ case CHR('1'): case CHR('2'): case CHR('3'): case CHR('4'):
+ case CHR('5'): case CHR('6'): case CHR('7'): case CHR('8'):
+ case CHR('9'):
+ NOTE(REG_UBACKREF);
+ RETV(BACKREF, (chr)DIGITVAL(c));
+ break;
+ default:
+ if (iscalnum(c)) {
+ NOTE(REG_UBSALNUM);
+ NOTE(REG_UUNSPEC);
+ }
+ RETV(PLAIN, c);
+ break;
+ }
+
+ assert(NOTREACHED);
+}
+
+/*
+ - skip - skip white space and comments in expanded form
+ ^ static VOID skip(struct vars *);
+ */
+static VOID
+skip(v)
+struct vars *v;
+{
+ chr *start = v->now;
+
+ assert(v->cflags®_EXPANDED);
+
+ for (;;) {
+ while (!ATEOS() && iscspace(*v->now))
+ v->now++;
+ if (ATEOS() || *v->now != CHR('#'))
+ break; /* NOTE BREAK OUT */
+ assert(NEXT1('#'));
+ while (!ATEOS() && *v->now != CHR('\n'))
+ v->now++;
+ /* leave the newline to be picked up by the iscspace loop */
+ }
+
+ if (v->now != start)
+ NOTE(REG_UNONPOSIX);
+}
+
+/*
+ - newline - return the chr for a newline
+ * This helps confine use of CHR to this source file.
+ ^ static chr newline(NOPARMS);
+ */
+static chr
+newline()
+{
+ return CHR('\n');
+}
+
+/*
+ - ch - return the chr sequence for regc_locale.c's fake collating element ch
+ * This helps confine use of CHR to this source file. Beware that the caller
+ * knows how long the sequence is.
+ ^ #ifdef REG_DEBUG
+ ^ static chr *ch(NOPARMS);
+ ^ #endif
+ */
+#ifdef REG_DEBUG
+static chr *
+ch()
+{
+ static chr chstr[] = { CHR('c'), CHR('h'), CHR('\0') };
+
+ return chstr;
+}
+#endif
+
+/*
+ - chrnamed - return the chr known by a given (chr string) name
+ * The code is a bit clumsy, but this routine gets only such specialized
+ * use that it hardly matters.
+ ^ static chr chrnamed(struct vars *, chr *, chr *, pchr);
+ */
+static chr
+chrnamed(v, startp, endp, lastresort)
+struct vars *v;
+chr *startp; /* start of name */
+chr *endp; /* just past end of name */
+pchr lastresort; /* what to return if name lookup fails */
+{
+ celt c;
+ int errsave;
+ int e;
+ struct cvec *cv;
+
+ errsave = v->err;
+ v->err = 0;
+ c = element(v, startp, endp);
+ e = v->err;
+ v->err = errsave;
+
+ if (e != 0)
+ return (chr)lastresort;
+
+ cv = range(v, c, c, 0);
+ if (cv->nchrs == 0)
+ return (chr)lastresort;
+ return cv->chrs[0];
+}
OSDN Git Service
