re.c revision 117803
116Salm/* re.c: This file contains the regular expression interface routines for 216Salm the ed line editor. */ 316Salm/*- 41057Salm * Copyright (c) 1993 Andrew Moore, Talke Studio. 516Salm * All rights reserved. 616Salm * 716Salm * Redistribution and use in source and binary forms, with or without 816Salm * modification, are permitted provided that the following conditions 916Salm * are met: 1016Salm * 1. Redistributions of source code must retain the above copyright 1116Salm * notice, this list of conditions and the following disclaimer. 1216Salm * 2. Redistributions in binary form must reproduce the above copyright 1316Salm * notice, this list of conditions and the following disclaimer in the 1416Salm * documentation and/or other materials provided with the distribution. 1516Salm * 161057Salm * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1716Salm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1816Salm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 191057Salm * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 2016Salm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2116Salm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2216Salm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2316Salm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2416Salm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2516Salm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2616Salm * SUCH DAMAGE. 2716Salm */ 2816Salm 2999109Sobrien#include <sys/cdefs.h> 3099109Sobrien__FBSDID("$FreeBSD: head/bin/ed/re.c 117803 2003-07-20 10:24:09Z ru $"); 3116Salm 3216Salm#include "ed.h" 3316Salm 341057Salm 3516Salmextern int patlock; 3616Salm 3781220Smikeconst char *errmsg = ""; 3816Salm 398855Srgrimes/* get_compiled_pattern: return pointer to compiled pattern from command 401057Salm buffer */ 4116Salmpattern_t * 4290109Simpget_compiled_pattern(void) 4316Salm{ 44117803Sru static pattern_t *expr = NULL; 4581220Smike static char error[1024]; 4616Salm 47117803Sru char *exprs; 481057Salm char delimiter; 4916Salm int n; 5016Salm 511057Salm if ((delimiter = *ibufp) == ' ') { 5281220Smike errmsg = "invalid pattern delimiter"; 5316Salm return NULL; 541057Salm } else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) { 55117803Sru if (!expr) 5681220Smike errmsg = "no previous pattern"; 57117803Sru return expr; 58117803Sru } else if ((exprs = extract_pattern(delimiter)) == NULL) 5916Salm return NULL; 6016Salm /* buffer alloc'd && not reserved */ 61117803Sru if (expr && !patlock) 62117803Sru regfree(expr); 63117803Sru else if ((expr = (pattern_t *) malloc(sizeof(pattern_t))) == NULL) { 6416Salm fprintf(stderr, "%s\n", strerror(errno)); 6581220Smike errmsg = "out of memory"; 6616Salm return NULL; 6716Salm } 6816Salm patlock = 0; 69117803Sru if ((n = regcomp(expr, exprs, 0))) { 70117803Sru regerror(n, expr, error, sizeof error); 7181220Smike errmsg = error; 72117803Sru free(expr); 73117803Sru return expr = NULL; 7416Salm } 75117803Sru return expr; 7616Salm} 7716Salm 7816Salm 791057Salm/* extract_pattern: copy a pattern string from the command buffer; return 801057Salm pointer to the copy */ 8116Salmchar * 8290109Simpextract_pattern(int delimiter) 8316Salm{ 841057Salm static char *lhbuf = NULL; /* buffer */ 851057Salm static int lhbufsz = 0; /* buffer size */ 861057Salm 8716Salm char *nd; 8816Salm int len; 8916Salm 901057Salm for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++) 9116Salm switch (*nd) { 9216Salm default: 9316Salm break; 9416Salm case '[': 951057Salm if ((nd = parse_char_class(++nd)) == NULL) { 9681220Smike errmsg = "unbalanced brackets ([])"; 9716Salm return NULL; 9816Salm } 9916Salm break; 10016Salm case '\\': 10116Salm if (*++nd == '\n') { 10281220Smike errmsg = "trailing backslash (\\)"; 10316Salm return NULL; 10416Salm } 10516Salm break; 10616Salm } 10716Salm len = nd - ibufp; 1081057Salm REALLOC(lhbuf, lhbufsz, len + 1, NULL); 10916Salm memcpy(lhbuf, ibufp, len); 11016Salm lhbuf[len] = '\0'; 11116Salm ibufp = nd; 1121057Salm return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf; 11316Salm} 11416Salm 11516Salm 1161057Salm/* parse_char_class: expand a POSIX character class */ 11716Salmchar * 11890109Simpparse_char_class(char *s) 11916Salm{ 12016Salm int c, d; 12116Salm 12216Salm if (*s == '^') 12316Salm s++; 12416Salm if (*s == ']') 12516Salm s++; 12616Salm for (; *s != ']' && *s != '\n'; s++) 12716Salm if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) 12816Salm for (s++, c = *++s; *s != ']' || c != d; s++) 12916Salm if ((c = *s) == '\n') 13016Salm return NULL; 13116Salm return (*s == ']') ? s : NULL; 13216Salm} 133