diff --git a/usr.bin/tsort/tsort.1 b/usr.bin/tsort/tsort.1 index fb6fa32812ac..3b57da5b47c0 100644 --- a/usr.bin/tsort/tsort.1 +++ b/usr.bin/tsort/tsort.1 @@ -1,86 +1,91 @@ .\" Copyright (c) 1990, 1993, 1994 .\" The Regents of the University of California. All rights reserved. .\" .\" This manual is derived from one contributed to Berkeley by .\" Michael Rendell of Memorial University of Newfoundland. .\" .\" 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. .\" .\" @(#)tsort.1 8.3 (Berkeley) 4/1/94 .\" .Dd April 1, 1994 .Dt TSORT 1 .Os .Sh NAME .Nm tsort .Nd topological sort of a directed graph .Sh SYNOPSIS .Nm tsort .Op Fl d .Op Fl l +.Op Fl q .Op Ar file .Sh DESCRIPTION .Nm Tsort takes a list of pairs of node names representing directed arcs in a graph and prints the nodes in topological order on standard output. Input is taken from the named .Ar file , or from standard input if no file is given. .Pp Node names in the input are separated by white space and there must be an even number of node pairs. .Pp Presence of a node in a graph can be represented by an arc from the node to itself. This is useful when a node is not connected to any other nodes. .Pp If the graph contains a cycle (and therefore cannot be properly sorted), one of the arcs in the cycle is ignored and the sort continues. Cycles are reported on standard error. .Pp The options are as follows: .Bl -tag -width Ds .It Fl d Turn on debugging. .It Fl l Search for and display the longest cycle. Can take a very long time. +.It Fl q +Do not display informational messages about cycles. This is primarily +intended for building libraries, where optimal ordering is not critical, +and cycles occur often. .El .Sh SEE ALSO .Xr ar 1 .Sh HISTORY A .Nm command appeared in .At v7 . This .Nm tsort command and manual page are derived from sources contributed to Berkeley by Michael Rendell of Memorial University of Newfoundland. diff --git a/usr.bin/tsort/tsort.c b/usr.bin/tsort/tsort.c index 0ad452cbe86f..37ce8565afc1 100644 --- a/usr.bin/tsort/tsort.c +++ b/usr.bin/tsort/tsort.c @@ -1,431 +1,436 @@ /* * Copyright (c) 1989, 1993, 1994 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Michael Rendell of Memorial University of Newfoundland. * * 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. * - * $Id$ + * $Id: tsort.c,v 1.3 1996/06/10 16:12:43 phk Exp $ */ #ifndef lint static char copyright[] = "@(#) Copyright (c) 1989, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint -static char sccsid[] = "@(#)tsort.c 8.2 (Berkeley) 3/30/94"; +static char sccsid[] = "@(#)tsort.c 8.3 (Berkeley) 5/4/95"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include /* * Topological sort. Input is a list of pairs of strings separated by * white space (spaces, tabs, and/or newlines); strings are written to * standard output in sorted order, one per line. * * usage: - * tsort [-l] [inputfile] + * tsort [-dlq] [inputfile] * If no input file is specified, standard input is read. * * Should be compatable with AT&T tsort HOWEVER the output is not identical * (i.e. for most graphs there is more than one sorted order, and this tsort * usually generates a different one then the AT&T tsort). Also, cycle * reporting seems to be more accurate in this version (the AT&T tsort * sometimes says a node is in a cycle when it isn't). * * Michael Rendell, michael@stretch.cs.mun.ca - Feb 26, '90 */ #define HASHSIZE 53 /* doesn't need to be big */ #define NF_MARK 0x1 /* marker for cycle detection */ #define NF_ACYCLIC 0x2 /* this node is cycle free */ #define NF_NODEST 0x4 /* Unreachable */ typedef struct node_str NODE; struct node_str { NODE **n_prevp; /* pointer to previous node's n_next */ NODE *n_next; /* next node in graph */ NODE **n_arcs; /* array of arcs to other nodes */ int n_narcs; /* number of arcs in n_arcs[] */ int n_arcsize; /* size of n_arcs[] array */ int n_refcnt; /* # of arcs pointing to this node */ int n_flags; /* NF_* */ char n_name[1]; /* name of this node */ }; typedef struct _buf { char *b_buf; int b_bsize; } BUF; DB *db; NODE *graph, **cycle_buf, **longest_cycle; -int debug, longest; +int debug, longest, quiet; void add_arc __P((char *, char *)); int find_cycle __P((NODE *, NODE *, int, int)); NODE *get_node __P((char *)); void *grow_buf __P((void *, int)); void remove_node __P((NODE *)); void tsort __P((void)); void usage __P((void)); int main(argc, argv) int argc; char *argv[]; { register BUF *b; register int c, n; FILE *fp; int bsize, ch, nused; BUF bufs[2]; - while ((ch = getopt(argc, argv, "dl")) != EOF) + while ((ch = getopt(argc, argv, "dlq")) != EOF) switch (ch) { case 'd': debug = 1; break; case 'l': longest = 1; break; + case 'q': + quiet = 1; + break; case '?': default: usage(); } argc -= optind; argv += optind; switch (argc) { case 0: fp = stdin; break; case 1: if ((fp = fopen(*argv, "r")) == NULL) err(1, "%s", *argv); break; default: usage(); } for (b = bufs, n = 2; --n >= 0; b++) b->b_buf = grow_buf(NULL, b->b_bsize = 1024); /* parse input and build the graph */ for (n = 0, c = getc(fp);;) { while (c != EOF && isspace(c)) c = getc(fp); if (c == EOF) break; nused = 0; b = &bufs[n]; bsize = b->b_bsize; do { b->b_buf[nused++] = c; if (nused == bsize) b->b_buf = grow_buf(b->b_buf, bsize *= 2); c = getc(fp); } while (c != EOF && !isspace(c)); b->b_buf[nused] = '\0'; b->b_bsize = bsize; if (n) add_arc(bufs[0].b_buf, bufs[1].b_buf); n = !n; } (void)fclose(fp); if (n) errx(1, "odd data count"); /* do the sort */ tsort(); exit(0); } /* double the size of oldbuf and return a pointer to the new buffer. */ void * grow_buf(bp, size) void *bp; int size; { if ((bp = realloc(bp, (u_int)size)) == NULL) err(1, NULL); return (bp); } /* * add an arc from node s1 to node s2 in the graph. If s1 or s2 are not in * the graph, then add them. */ void add_arc(s1, s2) char *s1, *s2; { register NODE *n1; NODE *n2; int bsize, i; n1 = get_node(s1); if (!strcmp(s1, s2)) return; n2 = get_node(s2); /* * Check if this arc is already here. */ for (i = 0; i < n1->n_narcs; i++) if (n1->n_arcs[i] == n2) return; /* * Add it. */ if (n1->n_narcs == n1->n_arcsize) { if (!n1->n_arcsize) n1->n_arcsize = 10; bsize = n1->n_arcsize * sizeof(*n1->n_arcs) * 2; n1->n_arcs = grow_buf(n1->n_arcs, bsize); n1->n_arcsize = bsize / sizeof(*n1->n_arcs); } n1->n_arcs[n1->n_narcs++] = n2; ++n2->n_refcnt; } /* Find a node in the graph (insert if not found) and return a pointer to it. */ NODE * get_node(name) char *name; { DBT data, key; NODE *n; if (db == NULL && (db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) err(1, "db: %s", name); key.data = name; key.size = strlen(name) + 1; switch ((*db->get)(db, &key, &data, 0)) { case 0: bcopy(data.data, &n, sizeof(n)); return (n); case 1: break; default: case -1: err(1, "db: %s", name); } if ((n = malloc(sizeof(NODE) + key.size)) == NULL) err(1, NULL); n->n_narcs = 0; n->n_arcsize = 0; n->n_arcs = NULL; n->n_refcnt = 0; n->n_flags = 0; bcopy(name, n->n_name, key.size); /* Add to linked list. */ if ((n->n_next = graph) != NULL) graph->n_prevp = &n->n_next; n->n_prevp = &graph; graph = n; /* Add to hash table. */ data.data = &n; data.size = sizeof(n); if ((*db->put)(db, &key, &data, 0)) err(1, "db: %s", name); return (n); } /* * Clear the NODEST flag from all nodes. */ void clear_cycle() { NODE *n; for (n = graph; n != NULL; n = n->n_next) n->n_flags &= ~NF_NODEST; } /* do topological sort on graph */ void tsort() { register NODE *n, *next; register int cnt, i; while (graph != NULL) { /* * Keep getting rid of simple cases until there are none left, * if there are any nodes still in the graph, then there is * a cycle in it. */ do { for (cnt = 0, n = graph; n != NULL; n = next) { next = n->n_next; if (n->n_refcnt == 0) { remove_node(n); ++cnt; } } } while (graph != NULL && cnt); if (graph == NULL) break; if (!cycle_buf) { /* * Allocate space for two cycle logs - one to be used * as scratch space, the other to save the longest * cycle. */ for (cnt = 0, n = graph; n != NULL; n = n->n_next) ++cnt; cycle_buf = malloc((u_int)sizeof(NODE *) * cnt); longest_cycle = malloc((u_int)sizeof(NODE *) * cnt); if (cycle_buf == NULL || longest_cycle == NULL) err(1, NULL); } for (n = graph; n != NULL; n = n->n_next) if (!(n->n_flags & NF_ACYCLIC)) - if (cnt = find_cycle(n, n, 0, 0)) { - warnx("cycle in data"); - for (i = 0; i < cnt; i++) - warnx("%s", - longest_cycle[i]->n_name); + if ((cnt = find_cycle(n, n, 0, 0))) { + if (!quiet) { + warnx("cycle in data"); + for (i = 0; i < cnt; i++) + warnx("%s", + longest_cycle[i]->n_name); + } remove_node(n); clear_cycle(); break; } else { /* to avoid further checks */ n->n_flags |= NF_ACYCLIC; clear_cycle(); } if (n == NULL) errx(1, "internal error -- could not find cycle"); } } /* print node and remove from graph (does not actually free node) */ void remove_node(n) register NODE *n; { register NODE **np; register int i; (void)printf("%s\n", n->n_name); for (np = n->n_arcs, i = n->n_narcs; --i >= 0; np++) --(*np)->n_refcnt; n->n_narcs = 0; *n->n_prevp = n->n_next; if (n->n_next) n->n_next->n_prevp = n->n_prevp; } /* look for the longest? cycle from node from to node to. */ int find_cycle(from, to, longest_len, depth) NODE *from, *to; int depth, longest_len; { register NODE **np; register int i, len; /* * avoid infinite loops and ignore portions of the graph known * to be acyclic */ if (from->n_flags & (NF_NODEST|NF_MARK|NF_ACYCLIC)) return (0); from->n_flags |= NF_MARK; for (np = from->n_arcs, i = from->n_narcs; --i >= 0; np++) { cycle_buf[depth] = *np; if (*np == to) { if (depth + 1 > longest_len) { longest_len = depth + 1; (void)memcpy((char *)longest_cycle, (char *)cycle_buf, longest_len * sizeof(NODE *)); } } else { if ((*np)->n_flags & (NF_MARK|NF_ACYCLIC|NF_NODEST)) continue; len = find_cycle(*np, to, longest_len, depth + 1); if (debug) (void)printf("%*s %s->%s %d\n", depth, "", from->n_name, to->n_name, len); if (len == 0) (*np)->n_flags |= NF_NODEST; if (len > longest_len) longest_len = len; if (len > 0 && !longest) break; } } from->n_flags &= ~NF_MARK; return (longest_len); } void usage() { - (void)fprintf(stderr, "usage: tsort [-dl] [file]\n"); + (void)fprintf(stderr, "usage: tsort [-dlq] [file]\n"); exit(1); }