tr_str.c (7430B)
- // SPDX-License-Identifier: BSD-3-Clause
- /* $OpenBSD: str.c,v 1.15 2023/05/04 16:08:29 tb 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.
- */
- #define _POSIX_C_SOURCE 202405L
- #include "./tr_str.h"
- #include "./reallocarray.h"
- #include <assert.h>
- #include <ctype.h>
- #include <err.h>
- #include <errno.h>
- #include <stddef.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <sys/types.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(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(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(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
- {
- const char *name;
- int (*func)(int);
- int *set;
- } CLASS;
- static CLASS classes[] = {
- /* clang-format off */
- { "alnum", isalnum, NULL, },
- { "alpha", isalpha, NULL, },
- { "blank", isblank, NULL, },
- { "cntrl", iscntrl, NULL, },
- { "digit", isdigit, NULL, },
- { "graph", isgraph, NULL, },
- { "lower", islower, NULL, },
- { "print", isprint, NULL, },
- { "punct", ispunct, NULL, },
- { "space", isspace, NULL, },
- { "upper", isupper, NULL, },
- { "xdigit", isxdigit, NULL, },
- /* clang-format on */
- };
- 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)
- {
- len = NCHARS + 1;
- assert(len != 0);
- cp->set = reallocarray(NULL, len, 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;
- }
- cp->set[len++] = OOBCH;
- assert(len != 0);
- 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(const void *a, const void *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(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(STR *s)
- {
- int stopval;
- unsigned char *savestart;
- savestart = s->str;
- stopval = *++s->str == '\\' ? backslash(s) : *s->str++;
- if(stopval < (unsigned char)s->lastch)
- {
- s->str = savestart;
- return (0);
- }
- s->cnt = stopval - s->lastch + 1;
- s->state = RANGE;
- --s->lastch;
- return (1);
- }
- static void
- genseq(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);
- }
- }