/* $OpenBSD: str.c,v 1.14 2021/11/02 03:09:15 cheloha Exp $ */ /* $NetBSD: str.c,v 1.7 1995/08/31 22:13:47 jtc Exp $ */ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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. */ #include #include #include #include #include #include #include #include #include #include "extern.h" static int backslash(STR *); static int bracket(STR *); static int c_class(const void *, const void *); static void genclass(STR *); static void genequiv(STR *); static int genrange(STR *); static void genseq(STR *); int next(s) STR *s; { int ch; switch (s->state) { case EOS: return (0); case INFINITE: return (1); case NORMAL: switch (ch = *s->str) { case '\0': s->state = EOS; return (0); case '\\': s->lastch = backslash(s); break; case '[': if (bracket(s)) return (next(s)); /* FALLTHROUGH */ default: ++s->str; s->lastch = ch; break; } /* We can start a range at any time. */ if (s->str[0] == '-' && genrange(s)) return (next(s)); return (1); case RANGE: if (s->cnt-- == 0) { s->state = NORMAL; return (next(s)); } ++s->lastch; return (1); case SEQUENCE: if (s->cnt-- == 0) { s->state = NORMAL; return (next(s)); } return (1); case SET: if ((s->lastch = s->set[s->cnt++]) == OOBCH) { s->state = NORMAL; return (next(s)); } return (1); default: return 0; } /* NOTREACHED */ } static int bracket(s) STR *s; { char *p; switch (s->str[1]) { case ':': /* "[:class:]" */ if ((p = strstr((char *)s->str + 2, ":]")) == NULL) return (0); *p = '\0'; s->str += 2; genclass(s); s->str = (unsigned char *)p + 2; return (1); case '=': /* "[=equiv=]" */ if ((p = strstr((char *)s->str + 2, "=]")) == NULL) return (0); s->str += 2; genequiv(s); return (1); default: /* "[\###*n]" or "[#*n]" */ if ((p = strpbrk((char *)s->str + 2, "*]")) == NULL) return (0); if (p[0] != '*' || strchr(p, ']') == NULL) return (0); s->str += 1; genseq(s); return (1); } /* NOTREACHED */ } typedef struct { char *name; int (*func)(int); int *set; } CLASS; static CLASS classes[] = { { "alnum", isalnum, }, { "alpha", isalpha, }, { "blank", isblank, }, { "cntrl", iscntrl, }, { "digit", isdigit, }, { "graph", isgraph, }, { "lower", islower, }, { "print", isprint, }, { "punct", ispunct, }, { "space", isspace, }, { "upper", isupper, }, { "xdigit", isxdigit, }, }; static void genclass(STR *s) { CLASS *cp, tmp; size_t len; int i; tmp.name = (char *)s->str; if ((cp = (CLASS *)bsearch(&tmp, classes, sizeof(classes) / sizeof(CLASS), sizeof(CLASS), c_class)) == NULL) errx(1, "unknown class %s", s->str); /* * Generate the set of characters in the class if we haven't * already done so. */ if (cp->set == NULL) { cp->set = reallocarray(NULL, NCHARS + 1, sizeof(*cp->set)); if (cp->set == NULL) err(1, NULL); len = 0; for (i = 0; i < NCHARS; i++) { if (cp->func(i)) { cp->set[len] = i; len++; } } cp->set[len] = OOBCH; len++; cp->set = reallocarray(cp->set, len, sizeof(*cp->set)); if (cp->set == NULL) err(1, NULL); } s->cnt = 0; s->state = SET; s->set = cp->set; } static int c_class(a, b) const void *a, *b; { return (strcmp(((CLASS *)a)->name, ((CLASS *)b)->name)); } /* * English doesn't have any equivalence classes, so for now * we just syntax check and grab the character. */ static void genequiv(s) STR *s; { if (*s->str == '\\') { s->equiv[0] = backslash(s); if (*s->str != '=') errx(1, "misplaced equivalence equals sign"); } else { s->equiv[0] = s->str[0]; if (s->str[1] != '=') errx(1, "misplaced equivalence equals sign"); } s->str += 2; s->cnt = 0; s->state = SET; s->set = s->equiv; } static int genrange(s) STR *s; { int stopval; unsigned char *savestart; savestart = s->str; stopval = *++s->str == '\\' ? backslash(s) : *s->str++; if (stopval < (u_char)s->lastch) { s->str = savestart; return (0); } s->cnt = stopval - s->lastch + 1; s->state = RANGE; --s->lastch; return (1); } static void genseq(s) STR *s; { char *ep; if (s->which == STRING1) errx(1, "sequences only valid in string2"); if (*s->str == '\\') s->lastch = backslash(s); else s->lastch = *s->str++; if (*s->str != '*') errx(1, "misplaced sequence asterisk"); switch (*++s->str) { case '\\': s->cnt = backslash(s); break; case ']': s->cnt = 0; ++s->str; break; default: if (isdigit(*s->str)) { s->cnt = strtol((char *)s->str, &ep, 0); if (*ep == ']') { s->str = (unsigned char *)ep + 1; break; } } errx(1, "illegal sequence count"); /* NOTREACHED */ } s->state = s->cnt ? SEQUENCE : INFINITE; } /* * Translate \??? into a character. Up to 3 octal digits, if no digits either * an escape code or a literal character. */ static int backslash(STR *s) { size_t i; int ch, val; assert(*s->str == '\\'); s->str++; /* Empty escapes become plain backslashes. */ if (*s->str == '\0') { s->state = EOS; return ('\\'); } val = 0; for (i = 0; i < 3; i++) { if (s->str[i] < '0' || '7' < s->str[i]) break; val = val * 8 + s->str[i] - '0'; } if (i > 0) { if (val > UCHAR_MAX) errx(1, "octal value out of range: %d", val); s->str += i; return (val); } ch = *s->str++; switch (ch) { case 'a': /* escape characters */ return ('\7'); case 'b': return ('\b'); case 'f': return ('\f'); case 'n': return ('\n'); case 'r': return ('\r'); case 't': return ('\t'); case 'v': return ('\13'); default: /* \x" -> x */ return (ch); } }