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/* re.c: This file contains the regular expression interface routines for |
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the ed line editor. */ |
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/*- |
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* Copyright (c) 1993 Andrew Moore, Talke Studio. |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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|
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#include <sys/cdefs.h> |
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__FBSDID("$FreeBSD: release/7.0.0/bin/ed/re.c 172506 2007-10-10 16:59:15Z cvs2svn $"); |
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|
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#include "ed.h" |
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|
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|
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extern int patlock; |
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|
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const char *errmsg = ""; |
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|
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/* get_compiled_pattern: return pointer to compiled pattern from command |
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buffer */ |
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pattern_t * |
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get_compiled_pattern(void) |
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{ |
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static pattern_t *expr = NULL; |
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static char error[1024]; |
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|
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char *exprs; |
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char delimiter; |
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int n; |
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|
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if ((delimiter = *ibufp) == ' ') { |
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errmsg = "invalid pattern delimiter"; |
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return NULL; |
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} else if (delimiter == '\n' || *++ibufp == '\n' || *ibufp == delimiter) { |
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if (!expr) |
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errmsg = "no previous pattern"; |
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return expr; |
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} else if ((exprs = extract_pattern(delimiter)) == NULL) |
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return NULL; |
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/* buffer alloc'd && not reserved */ |
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if (expr && !patlock) |
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regfree(expr); |
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else if ((expr = (pattern_t *) malloc(sizeof(pattern_t))) == NULL) { |
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fprintf(stderr, "%s\n", strerror(errno)); |
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errmsg = "out of memory"; |
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return NULL; |
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} |
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patlock = 0; |
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if ((n = regcomp(expr, exprs, 0))) { |
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regerror(n, expr, error, sizeof error); |
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errmsg = error; |
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free(expr); |
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return expr = NULL; |
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} |
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return expr; |
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} |
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|
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|
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/* extract_pattern: copy a pattern string from the command buffer; return |
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pointer to the copy */ |
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char * |
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extract_pattern(int delimiter) |
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{ |
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static char *lhbuf = NULL; /* buffer */ |
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static int lhbufsz = 0; /* buffer size */ |
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|
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char *nd; |
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int len; |
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|
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for (nd = ibufp; *nd != delimiter && *nd != '\n'; nd++) |
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switch (*nd) { |
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default: |
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break; |
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case '[': |
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if ((nd = parse_char_class(++nd)) == NULL) { |
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errmsg = "unbalanced brackets ([])"; |
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return NULL; |
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} |
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break; |
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case '\\': |
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if (*++nd == '\n') { |
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errmsg = "trailing backslash (\\)"; |
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return NULL; |
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} |
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break; |
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} |
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len = nd - ibufp; |
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REALLOC(lhbuf, lhbufsz, len + 1, NULL); |
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memcpy(lhbuf, ibufp, len); |
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lhbuf[len] = '\0'; |
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ibufp = nd; |
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return (isbinary) ? NUL_TO_NEWLINE(lhbuf, len) : lhbuf; |
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} |
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|
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|
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/* parse_char_class: expand a POSIX character class */ |
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char * |
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parse_char_class(char *s) |
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{ |
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int c, d; |
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|
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if (*s == '^') |
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s++; |
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if (*s == ']') |
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s++; |
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for (; *s != ']' && *s != '\n'; s++) |
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if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) |
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for (s++, c = *++s; *s != ']' || c != d; s++) |
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if ((c = *s) == '\n') |
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return NULL; |
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return (*s == ']') ? s : NULL; |
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} |
