diff options
author | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
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committer | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
commit | d6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch) | |
tree | ece253b876159b39c620e62b6c9b1174642e070e /usr.bin/look |
initial import of NetBSD tree
Diffstat (limited to 'usr.bin/look')
-rw-r--r-- | usr.bin/look/Makefile | 6 | ||||
-rw-r--r-- | usr.bin/look/look.1 | 106 | ||||
-rw-r--r-- | usr.bin/look/look.c | 336 | ||||
-rw-r--r-- | usr.bin/look/pathnames.h | 38 |
4 files changed, 486 insertions, 0 deletions
diff --git a/usr.bin/look/Makefile b/usr.bin/look/Makefile new file mode 100644 index 00000000000..f0fc7ed8280 --- /dev/null +++ b/usr.bin/look/Makefile @@ -0,0 +1,6 @@ +# $NetBSD: Makefile,v 1.3 1994/12/23 01:10:55 jtc Exp $ +# @(#)Makefile 8.1 (Berkeley) 6/9/93 + +PROG= look + +.include <bsd.prog.mk> diff --git a/usr.bin/look/look.1 b/usr.bin/look/look.1 new file mode 100644 index 00000000000..bb955fdb5f9 --- /dev/null +++ b/usr.bin/look/look.1 @@ -0,0 +1,106 @@ +.\" $NetBSD: look.1,v 1.3 1994/12/23 01:10:59 jtc Exp $ +.\" +.\" Copyright (c) 1990, 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. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. 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. +.\" +.\" @(#)look.1 8.1 (Berkeley) 6/14/93 +.\" +.Dd June 14, 1993 +.Dt LOOK 1 +.Os +.Sh NAME +.Nm look +.Nd display lines beginning with a given string +.Sh SYNOPSIS +.Nm look +.Op Fl df +.Op Fl t Ar termchar +.Ar string +.Op Ar file +.Sh DESCRIPTION +The +.Nm look +utility displays any lines in +.Ar file +which contain +.Ar string +as a prefix. +As +.Nm look +performs a binary search, the lines in +.Ar file +must be sorted. +.Pp +If +.Ar file +is not specified, the file +.Pa /usr/share/dict/words +is used, only alphanumeric characters are compared and the case of +alphabetic characters is ignored. +.Pp +Options: +.Bl -tag -width Ds +.It Fl d +Dictionary character set and order, i.e. only alphanumeric characters +are compared. +.It Fl f +Ignore the case of alphabetic characters. +.It Fl t +Specify a string termination character, i.e. only the characters +in +.Ar string +up to and including the first occurrence of +.Ar termchar +are compared. +.El +.Pp +The +.Nm look +utility exits 0 if one or more lines were found and displayed, +1 if no lines were found, and >1 if an error occurred. +.Sh FILES +.Bl -tag -width /usr/share/dict/words -compact +.It Pa /usr/share/dict/words +the dictionary +.El +.Sh SEE ALSO +.Xr grep 1 , +.Xr sort 1 +.Sh COMPATIBILITY +The original manual page stated that tabs and blank characters participated +in comparisons when the +.Fl d +option was specified. +This was incorrect and the current man page matches the historic +implementation. +.Sh HISTORY +.Nm Look +appeared in Version 7 AT&T Unix. diff --git a/usr.bin/look/look.c b/usr.bin/look/look.c new file mode 100644 index 00000000000..6e95ffac390 --- /dev/null +++ b/usr.bin/look/look.c @@ -0,0 +1,336 @@ +/* $NetBSD: look.c,v 1.7 1995/08/31 22:41:02 jtc Exp $ */ + +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * David Hitz of Auspex Systems, Inc. + * + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. 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. + */ + +#ifndef lint +static char copyright[] = +"@(#) Copyright (c) 1991, 1993\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +#if 0 +static char sccsid[] = "@(#)look.c 8.2 (Berkeley) 5/4/95"; +#endif +static char rcsid[] = "$NetBSD: look.c,v 1.7 1995/08/31 22:41:02 jtc Exp $"; +#endif /* not lint */ + +/* + * look -- find lines in a sorted list. + * + * The man page said that TABs and SPACEs participate in -d comparisons. + * In fact, they were ignored. This implements historic practice, not + * the manual page. + */ + +#include <sys/types.h> +#include <sys/mman.h> +#include <sys/stat.h> + +#include <ctype.h> +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <err.h> + +#include "pathnames.h" + +/* + * FOLD and DICT convert characters to a normal form for comparison, + * according to the user specified flags. + * + * DICT expects integers because it uses a non-character value to + * indicate a character which should not participate in comparisons. + */ +#define EQUAL 0 +#define GREATER 1 +#define LESS (-1) +#define NO_COMPARE (-2) + +#define FOLD(c) (isascii(c) && isupper(c) ? tolower(c) : (c)) +#define DICT(c) (isascii(c) && isalnum(c) ? (c) : NO_COMPARE) + +int dflag, fflag; + +char *binary_search __P((char *, char *, char *)); +int compare __P((char *, char *, char *)); +char *linear_search __P((char *, char *, char *)); +int look __P((char *, char *, char *)); +void print_from __P((char *, char *, char *)); +void usage __P((void)); + +int +main(argc, argv) + int argc; + char *argv[]; +{ + struct stat sb; + int ch, fd, termchar; + char *back, *file, *front, *string, *p; + + file = _PATH_WORDS; + termchar = '\0'; + while ((ch = getopt(argc, argv, "dft:")) != EOF) + switch(ch) { + case 'd': + dflag = 1; + break; + case 'f': + fflag = 1; + break; + case 't': + termchar = *optarg; + break; + case '?': + default: + usage(); + } + argc -= optind; + argv += optind; + + switch (argc) { + case 2: /* Don't set -df for user. */ + string = *argv++; + file = *argv; + break; + case 1: /* But set -df by default. */ + dflag = fflag = 1; + string = *argv; + break; + default: + usage(); + } + + if (termchar != '\0' && (p = strchr(string, termchar)) != NULL) + *++p = '\0'; + + if ((fd = open(file, O_RDONLY, 0)) < 0 || fstat(fd, &sb)) + err(2, "%s", file); + if (sb.st_size > SIZE_T_MAX) + err(2, "%s: %s", file, strerror(EFBIG)); + if ((front = mmap(NULL, + (size_t)sb.st_size, PROT_READ, 0, fd, (off_t)0)) == NULL) + err(2, "%s", file); + back = front + sb.st_size; + exit(look(string, front, back)); +} + +int +look(string, front, back) + char *string, *front, *back; +{ + register int ch; + register char *readp, *writep; + + /* Reformat string string to avoid doing it multiple times later. */ + for (readp = writep = string; ch = *readp++;) { + if (fflag) + ch = FOLD(ch); + if (dflag) + ch = DICT(ch); + if (ch != NO_COMPARE) + *(writep++) = ch; + } + *writep = '\0'; + + front = binary_search(string, front, back); + front = linear_search(string, front, back); + + if (front) + print_from(string, front, back); + return (front ? 0 : 1); +} + + +/* + * Binary search for "string" in memory between "front" and "back". + * + * This routine is expected to return a pointer to the start of a line at + * *or before* the first word matching "string". Relaxing the constraint + * this way simplifies the algorithm. + * + * Invariants: + * front points to the beginning of a line at or before the first + * matching string. + * + * back points to the beginning of a line at or after the first + * matching line. + * + * Base of the Invariants. + * front = NULL; + * back = EOF; + * + * Advancing the Invariants: + * + * p = first newline after halfway point from front to back. + * + * If the string at "p" is not greater than the string to match, + * p is the new front. Otherwise it is the new back. + * + * Termination: + * + * The definition of the routine allows it return at any point, + * since front is always at or before the line to print. + * + * In fact, it returns when the chosen "p" equals "back". This + * implies that there exists a string is least half as long as + * (back - front), which in turn implies that a linear search will + * be no more expensive than the cost of simply printing a string or two. + * + * Trying to continue with binary search at this point would be + * more trouble than it's worth. + */ +#define SKIP_PAST_NEWLINE(p, back) \ + while (p < back && *p++ != '\n'); + +char * +binary_search(string, front, back) + register char *string, *front, *back; +{ + register char *p; + + p = front + (back - front) / 2; + SKIP_PAST_NEWLINE(p, back); + + /* + * If the file changes underneath us, make sure we don't + * infinitely loop. + */ + while (p < back && back > front) { + if (compare(string, p, back) == GREATER) + front = p; + else + back = p; + p = front + (back - front) / 2; + SKIP_PAST_NEWLINE(p, back); + } + return (front); +} + +/* + * Find the first line that starts with string, linearly searching from front + * to back. + * + * Return NULL for no such line. + * + * This routine assumes: + * + * o front points at the first character in a line. + * o front is before or at the first line to be printed. + */ +char * +linear_search(string, front, back) + char *string, *front, *back; +{ + while (front < back) { + switch (compare(string, front, back)) { + case EQUAL: /* Found it. */ + return (front); + break; + case LESS: /* No such string. */ + return (NULL); + break; + case GREATER: /* Keep going. */ + break; + } + SKIP_PAST_NEWLINE(front, back); + } + return (NULL); +} + +/* + * Print as many lines as match string, starting at front. + */ +void +print_from(string, front, back) + register char *string, *front, *back; +{ + for (; front < back && compare(string, front, back) == EQUAL; ++front) { + for (; front < back && *front != '\n'; ++front) + if (putchar(*front) == EOF) + err(2, "stdout"); + if (putchar('\n') == EOF) + err(2, "stdout"); + } +} + +/* + * Return LESS, GREATER, or EQUAL depending on how the string1 compares with + * string2 (s1 ??? s2). + * + * o Matches up to len(s1) are EQUAL. + * o Matches up to len(s2) are GREATER. + * + * Compare understands about the -f and -d flags, and treats comparisons + * appropriately. + * + * The string "s1" is null terminated. The string s2 is '\n' terminated (or + * "back" terminated). + */ +int +compare(s1, s2, back) + register char *s1, *s2, *back; +{ + register int ch; + + for (; *s1 && s2 < back && *s2 != '\n'; ++s1, ++s2) { + ch = *s2; + if (fflag) + ch = FOLD(ch); + if (dflag) + ch = DICT(ch); + + if (ch == NO_COMPARE) { + ++s2; /* Ignore character in comparison. */ + continue; + } + if (*s1 != ch) + return (*s1 < ch ? LESS : GREATER); + } + return (*s1 ? GREATER : EQUAL); +} + +void +usage() +{ + (void)fprintf(stderr, "usage: look [-df] [-t char] string [file]\n"); + exit(2); +} diff --git a/usr.bin/look/pathnames.h b/usr.bin/look/pathnames.h new file mode 100644 index 00000000000..25ec1a56ca7 --- /dev/null +++ b/usr.bin/look/pathnames.h @@ -0,0 +1,38 @@ +/* $NetBSD: pathnames.h,v 1.3 1994/12/23 01:11:03 jtc Exp $ */ + +/* + * Copyright (c) 1989, 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. 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. + * + * @(#)pathnames.h 8.1 (Berkeley) 6/9/93 + */ + +#define _PATH_WORDS "/usr/share/dict/words" |