Importing NetBSD tsort
Change-Id: I110de8037b9253f4fe53cbe13dc8fc281aeea2ec
This commit is contained in:
Lionel Sambuc
parent
6e0ed9c90c
commit
8e5df35e84
14 changed files with 545 additions and 396 deletions
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@ -27,7 +27,7 @@ SUBDIR= add_route arp ash at backup banner basename btrace cal \
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stty svclog svrctl swifi sync synctree sysenv \
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stty svclog svrctl swifi sync synctree sysenv \
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syslogd tail tcpd tcpdp tcpstat tee telnet \
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syslogd tail tcpd tcpdp tcpstat tee telnet \
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telnetd term termcap tget time touch tr \
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telnetd term termcap tget time touch tr \
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truncate tsort tty udpstat umount uname unexpand \
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truncate tty udpstat umount uname unexpand \
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unstack update uud uue version vol wc \
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unstack update uud uue version vol wc \
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whereis which who write writeisofs fetch \
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whereis which who write writeisofs fetch \
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xargs yes zdump zmodem pkgin_cd \
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xargs yes zdump zmodem pkgin_cd \
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@ -1,4 +0,0 @@
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PROG= tsort
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MAN=
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.include <bsd.prog.mk>
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@ -1,356 +0,0 @@
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/* topo - topological sort Author: Kent Williams */
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/*
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** topo - perform a topological sort of the output of lorder.
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**
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** Usage : topo [infile] [outfile]
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**
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** Author: Kent Williams (williams@umaxc.weeg.uiowa.edu)
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*/
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#include <ctype.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdio.h>
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typedef struct __v {
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struct __v *next; /* link list node */
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int indegree, /* number of edges into this vertex */
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visited, /* depth-first search visited flag */
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on_the_path, /* used to find cycles */
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has_a_cycle; /* true if a cycle at this vertex */
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struct __e *out; /* outgoing edges from this vertex */
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char key[1]; /* name of this vertex */
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} vertex;
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typedef struct __e {
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struct __e *next; /* link list node */
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vertex *v; /* vertex to which this edge goes */
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} edge;
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int main(int argc, char **argv);
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void *xmalloc(size_t siz);
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edge *new_edge(vertex *v);
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char *copyupto(char *name, char *buf, int stop);
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int child_of(vertex *parent, vertex *child);
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vertex *add_v(char *s);
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void readin(void);
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void pushname(char *s);
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char *popname(void);
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void topo(void);
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void print_cycle(vertex *parent, vertex *child);
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void dfs(vertex *v);
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void check_cycles(void);
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/*
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** xmalloc -- standard do or die malloc front end.
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*/
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void *
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xmalloc(siz)
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size_t siz;
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{
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void *rval = (void *)malloc(siz);
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if(rval == NULL) {
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fputs("Out of memory.\n",stderr);
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exit(1);
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}
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return rval;
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}
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/*
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** edge allocater.
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*/
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edge *
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new_edge(v)
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vertex *v;
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{
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edge *rval;
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rval = (edge *)xmalloc(sizeof(edge));
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rval->v = v; return rval;
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}
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/*
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** copyupto - copy until you see the stop character.
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*/
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char *
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copyupto(name,buf,stop)
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char *name,*buf,stop;
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{
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while(*buf != '\0' && *buf != stop)
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*name++ = *buf++;
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*name = '\0';
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while(*buf != '\0' && isspace(*buf))
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buf++;
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return buf;
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}
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/*
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** find out if the vertex child is a child of the vertex parent.
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*/
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int
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child_of(parent,child)
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vertex *parent,*child;
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{
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edge *e;
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for(e = parent->out; e != NULL && e->v != child; e = e->next)
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;
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return e == NULL ? 0 : 1;
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}
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/*
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** the vertex set.
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**
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** add_v adds a vertex to the set if it's not already there.
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*/
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vertex *vset = NULL;
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vertex *
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add_v(s)
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char *s;
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{
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vertex *v,*last;
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/*
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** go looking for this key in the vertex set.
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*/
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for(last = v = vset; v != NULL && strcmp(v->key,s) != 0;
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last = v, v = v->next)
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;
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if(v != NULL) {
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/*
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** use the move-to-front heuristic to keep this from being
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** an O(N^2) algorithm.
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*/
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if(last != vset) {
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last->next = v->next;
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v->next = vset;
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vset = v;
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}
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return v;
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}
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v = (vertex *)xmalloc(sizeof(vertex) + strlen(s));
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v->out = NULL;
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strcpy(v->key,s);
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v->indegree =
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v->on_the_path =
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v->has_a_cycle =
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v->visited = 0;
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v->next = vset;
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vset = v;
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return v;
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}
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/*
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** readin -- read in the dependency pairs.
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*/
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void
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readin()
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{
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static char buf[128];
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static char name[64];
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char *bp;
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vertex *child,*parent;
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edge *e;
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while(fgets(buf,sizeof(buf),stdin) != NULL) {
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bp = buf + strlen(buf);
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if (bp > buf && bp[-1] == '\n') *--bp = 0;
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bp = copyupto(name,buf,' ');
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child = add_v(name);
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parent = add_v(bp);
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if(child != parent && !child_of(parent,child)) {
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e = new_edge(child);
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e->next = parent->out;
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parent->out = e;
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child->indegree++;
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}
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}
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}
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/*
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** the topological sort produces names of modules in reverse of
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** the order we want them in, so use a stack to hold the names
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** until we get them all, then pop them off to print them.
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*/
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struct name { struct name *next; char *s; }
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*namelist = NULL;
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void
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pushname(s)
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char *s;
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{
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struct name *x = (struct name *)xmalloc(sizeof(struct name));
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x->s = s;
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x->next = namelist;
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namelist = x;
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}
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char *
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popname() {
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char *rval;
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struct name *tmp;
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if(namelist == NULL)
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return NULL;
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tmp = namelist;
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rval = namelist->s;
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namelist = namelist->next;
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free(tmp);
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return rval;
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}
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/*
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** topo - do a topological sort of the dependency graph.
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*/
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void topo() {
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vertex *x = vset,*n;
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edge *e;
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vertex *outq = NULL,*tmp;
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#define insq(x) ((x->next = outq),(outq = x))
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#define deq() ((tmp = outq),(outq = outq->next),tmp)
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/*
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** find all vertices that don't depend on any other vertices
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** Since it breaks the "next" links to insert x into the queue,
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** x->next is saved before insq, to resume the list traversal.
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*/
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while (x != NULL) {
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n = x->next;
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if(x->indegree == 0) {
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insq(x);
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pushname(x->key);
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}
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x = n;
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}
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/*
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** for each vertex V with indegree of zero,
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** for each edge E from vertex V
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** subtract one from the indegree of the vertex V'
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** pointed to by E. If V' now has an indegree of zero,
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** add it to the set of vertices with indegree zero, and
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** push its name on the output stack.
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*/
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while(outq != NULL) {
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x = deq();
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e = x->out;
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while(e != NULL) {
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if(--(e->v->indegree) == 0) {
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insq(e->v);
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pushname(e->v->key);
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}
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e = e->next;
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}
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}
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/*
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** print the vertex names in opposite of the order they were
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** encountered.
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*/
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while(namelist != NULL)
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puts(popname());
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}
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/*
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** print_cycle --
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** A cycle has been detected between parent and child.
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** Start with the child, and look at each of its edges for
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** the parent.
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**
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** We know a vertex is on the path from the child to the parent
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** because the depth-first search sets on_the_path true for each
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** vertex it visits.
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*/
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void
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print_cycle(parent,child)
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vertex *parent, *child;
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{
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char *s;
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vertex *x;
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edge *e;
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for(x = child; x != parent; ) {
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pushname(x->key);
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for(e = x->out; e != NULL; e = e->next) {
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/*
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** stop looking for the path at the first node found
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** that's on the path. Watch out for cycles already
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** detected, because if you follow an edge into a cycle,
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** you're stuck in an infinite loop!
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*/
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if(e->v->on_the_path && !e->v->has_a_cycle) {
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x = e->v;
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break;
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}
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}
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}
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/*
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** print the name of the parent, and then names of each of the
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** vertices on the path from the child to the parent.
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*/
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fprintf(stderr,"%s\n",x->key);
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while((s = popname()) != NULL)
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fprintf(stderr,"%s\n",s);
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}
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/*
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** depth first search for cycles in the dependency graph.
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** See "Introduction to Algorithms" by Udi Manber Addison-Wesley 1989
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*/
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void
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dfs(v)
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vertex *v;
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{
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edge *e;
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if(v->visited) /* If you've been here before, don't go again! */
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return;
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v->visited++;
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v->on_the_path++; /* this node is on the path from the root. */
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/*
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** depth-first search all outgoing edges.
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*/
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for(e = v->out; e != NULL; e = e->next) {
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if(!e->v->visited)
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dfs(e->v);
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if(e->v->on_the_path) {
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fprintf(stderr,"cycle found between %s and %s\n",
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v->key,e->v->key);
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print_cycle(v,e->v);
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v->has_a_cycle++;
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}
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}
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v->on_the_path = 0;
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}
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/*
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** check cycles starts the recursive depth-first search from
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** each vertex in vset.
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*/
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void
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check_cycles()
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{
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vertex *v;
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for(v = vset; v != NULL; v = v->next)
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dfs(v);
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}
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/*
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** main program.
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*/
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int main(argc,argv)
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int argc;
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char **argv;
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{
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if(argc > 1 && freopen(argv[1],"r",stdin) == NULL) {
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perror(argv[1]);
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exit(0);
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}
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if(argc > 2 && freopen(argv[2],"w",stdout) == NULL) {
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perror(argv[2]);
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exit(0);
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}
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readin();
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check_cycles();
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topo();
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return(0);
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}
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@ -1,3 +1,9 @@
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20121205:
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The tsort tool has been also upgraded and is now also used during
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the build:
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# make -C usr.bin/tsort all install
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# cp share/mk/* /usr/share/mk
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20121205:
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20121205:
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lorder requires a newer version of sort, so to ensure it is present
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lorder requires a newer version of sort, so to ensure it is present
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do the following:
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do the following:
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@ -19,7 +19,7 @@ MAN= ash.1 at.1 banner.1 basename.1 \
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split.1 stty.1 svc.1 svrctl.1 \
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split.1 stty.1 svc.1 svrctl.1 \
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synctree.1 sysenv.1 sz.1 tail.1 tee.1 telnet.1 template.1 \
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synctree.1 sysenv.1 sz.1 tail.1 tee.1 telnet.1 template.1 \
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term.1 termcap.1 tget.1 time.1 tr.1 true.1 \
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term.1 termcap.1 tget.1 time.1 tr.1 true.1 \
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truncate.1 tsort.1 tty.1 umount.1 uname.1 unexpand.1 \
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truncate.1 tty.1 umount.1 uname.1 unexpand.1 \
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uud.1 uue.1 vol.1 wc.1 whereis.1 which.1 \
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uud.1 uue.1 vol.1 wc.1 whereis.1 which.1 \
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who.1 write.1 xargs.1 yap.1 yes.1 linkfarm.1 pkg_view.1
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who.1 write.1 xargs.1 yap.1 yes.1 linkfarm.1 pkg_view.1
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@ -1,27 +0,0 @@
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.TH TSORT 1
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.SH NAME
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tsort \- topological sort [IBM]
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.SH SYNOPSIS
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\fBtsort \fIfile\fR
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.br
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.de FL
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.TP
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|
||||||
\\fB\\$1\\fR
|
|
||||||
\\$2
|
|
||||||
..
|
|
||||||
.de EX
|
|
||||||
.TP 20
|
|
||||||
\\fB\\$1\\fR
|
|
||||||
# \\$2
|
|
||||||
..
|
|
||||||
.SH EXAMPLES
|
|
||||||
.TP 20
|
|
||||||
.B lorder *.s | tsort
|
|
||||||
# Give library ordering
|
|
||||||
.TP 20
|
|
||||||
.B ar cr libc.a \`lorder *.s | tsort\`
|
|
||||||
# Build library
|
|
||||||
.SH DESCRIPTION
|
|
||||||
.PP
|
|
||||||
\fITsort\fR accepts a file of lines containing ordered pairs and builds a
|
|
||||||
total ordering from the partial orderings.
|
|
||||||
|
|
@ -67,6 +67,7 @@
|
||||||
2012/10/17 12:00:00,tools/nbperf
|
2012/10/17 12:00:00,tools/nbperf
|
||||||
2012/10/17 12:00:00,tools/sed
|
2012/10/17 12:00:00,tools/sed
|
||||||
2012/10/17 12:00:00,tools/tic
|
2012/10/17 12:00:00,tools/tic
|
||||||
|
2012/10/17 12:00:00,tools/tsort
|
||||||
2012/10/17 12:00:00,usr.bin/gzip/Makefile
|
2012/10/17 12:00:00,usr.bin/gzip/Makefile
|
||||||
2012/10/17 12:00:00,usr.bin/indent
|
2012/10/17 12:00:00,usr.bin/indent
|
||||||
2012/10/17 12:00:00,usr.bin/join
|
2012/10/17 12:00:00,usr.bin/join
|
||||||
|
|
@ -76,6 +77,7 @@
|
||||||
2012/10/17 12:00:00,usr.bin/nbperf
|
2012/10/17 12:00:00,usr.bin/nbperf
|
||||||
2012/10/17 12:00:00,usr.bin/passwd/Makefile
|
2012/10/17 12:00:00,usr.bin/passwd/Makefile
|
||||||
2012/10/17 12:00:00,usr.bin/sort
|
2012/10/17 12:00:00,usr.bin/sort
|
||||||
|
2012/10/17 12:00:00,usr.bin/tsort
|
||||||
2012/10/17 12:00:00,usr.bin/xinstall
|
2012/10/17 12:00:00,usr.bin/xinstall
|
||||||
2012/10/17 12:00:00,usr.sbin/Makefile
|
2012/10/17 12:00:00,usr.sbin/Makefile
|
||||||
2012/10/17 12:00:00,usr.sbin/Makefile.inc
|
2012/10/17 12:00:00,usr.sbin/Makefile.inc
|
||||||
|
|
|
||||||
|
|
@ -510,12 +510,7 @@ _INSTRANLIB=${empty(PRESERVE):?-a "${RANLIB} -t":}
|
||||||
__archivebuild: .USE
|
__archivebuild: .USE
|
||||||
${_MKTARGET_BUILD}
|
${_MKTARGET_BUILD}
|
||||||
rm -f ${.TARGET}
|
rm -f ${.TARGET}
|
||||||
.if defined(__MINIX)
|
|
||||||
# LSC FIXME MINIX: We do not have yet imported tsort nor lorder
|
|
||||||
${AR} ${_ARFL} ${.TARGET} ${.ALLSRC:M*o}
|
|
||||||
.else
|
|
||||||
${AR} ${_ARFL} ${.TARGET} `NM=${NM} ${LORDER} ${.ALLSRC:M*o} | ${TSORT}`
|
${AR} ${_ARFL} ${.TARGET} `NM=${NM} ${LORDER} ${.ALLSRC:M*o} | ${TSORT}`
|
||||||
.endif # defined(__MINIX)
|
|
||||||
.endif
|
.endif
|
||||||
|
|
||||||
.if !target(__archiveinstall)
|
.if !target(__archiveinstall)
|
||||||
|
|
|
||||||
|
|
@ -61,7 +61,7 @@ LINT_BITS= lint lint2
|
||||||
SUBDIR= host-mkdep .WAIT compat .WAIT \
|
SUBDIR= host-mkdep .WAIT compat .WAIT \
|
||||||
binstall .WAIT mktemp .WAIT sed .WAIT \
|
binstall .WAIT mktemp .WAIT sed .WAIT \
|
||||||
genassym join \
|
genassym join \
|
||||||
lorder makewhatis mkdep mtree nbperf .WAIT \
|
lorder makewhatis mkdep mtree nbperf .WAIT tsort \
|
||||||
m4 \
|
m4 \
|
||||||
.WAIT mkfs.mfs \
|
.WAIT mkfs.mfs \
|
||||||
.WAIT yacc \
|
.WAIT yacc \
|
||||||
|
|
|
||||||
6
tools/tsort/Makefile
Normal file
6
tools/tsort/Makefile
Normal file
|
|
@ -0,0 +1,6 @@
|
||||||
|
# $NetBSD: Makefile,v 1.4 2002/12/08 20:20:06 thorpej Exp $
|
||||||
|
|
||||||
|
HOSTPROGNAME= ${_TOOL_PREFIX}tsort
|
||||||
|
HOST_SRCDIR= usr.bin/tsort
|
||||||
|
|
||||||
|
.include "${.CURDIR}/../Makefile.host"
|
||||||
|
|
@ -20,7 +20,8 @@ SUBDIR= \
|
||||||
sed seq \
|
sed seq \
|
||||||
sort stat su \
|
sort stat su \
|
||||||
tic \
|
tic \
|
||||||
uniq \
|
tsort \
|
||||||
|
uniq \
|
||||||
xinstall
|
xinstall
|
||||||
|
|
||||||
.if !defined(__MINIX)
|
.if !defined(__MINIX)
|
||||||
|
|
|
||||||
6
usr.bin/tsort/Makefile
Normal file
6
usr.bin/tsort/Makefile
Normal file
|
|
@ -0,0 +1,6 @@
|
||||||
|
# $NetBSD: Makefile,v 1.7 2009/04/14 22:15:27 lukem Exp $
|
||||||
|
# @(#)Makefile 8.1 (Berkeley) 6/9/93
|
||||||
|
|
||||||
|
PROG= tsort
|
||||||
|
|
||||||
|
.include <bsd.prog.mk>
|
||||||
87
usr.bin/tsort/tsort.1
Normal file
87
usr.bin/tsort/tsort.1
Normal file
|
|
@ -0,0 +1,87 @@
|
||||||
|
.\" $NetBSD: tsort.1,v 1.10 2003/08/07 11:16:50 agc Exp $
|
||||||
|
.\"
|
||||||
|
.\" 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. 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
|
||||||
|
.Op Fl l
|
||||||
|
.Op Fl q
|
||||||
|
.Op Ar file
|
||||||
|
.Sh DESCRIPTION
|
||||||
|
.Nm
|
||||||
|
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 names.
|
||||||
|
.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 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
|
||||||
|
command and manual page are derived from sources contributed to Berkeley by
|
||||||
|
Michael Rendell of Memorial University of Newfoundland.
|
||||||
433
usr.bin/tsort/tsort.c
Normal file
433
usr.bin/tsort/tsort.c
Normal file
|
|
@ -0,0 +1,433 @@
|
||||||
|
/* $NetBSD: tsort.c,v 1.23 2011/09/06 18:34:37 joerg Exp $ */
|
||||||
|
|
||||||
|
/*
|
||||||
|
* 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. 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.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#if HAVE_NBTOOL_CONFIG_H
|
||||||
|
#include "nbtool_config.h"
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include <sys/cdefs.h>
|
||||||
|
#if !defined(lint)
|
||||||
|
__COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\
|
||||||
|
The Regents of the University of California. All rights reserved.");
|
||||||
|
#if 0
|
||||||
|
static char sccsid[] = "@(#)tsort.c 8.3 (Berkeley) 5/4/95";
|
||||||
|
#endif
|
||||||
|
__RCSID("$NetBSD: tsort.c,v 1.23 2011/09/06 18:34:37 joerg Exp $");
|
||||||
|
#endif /* not lint */
|
||||||
|
|
||||||
|
#include <sys/types.h>
|
||||||
|
#include <ctype.h>
|
||||||
|
#include <db.h>
|
||||||
|
#include <err.h>
|
||||||
|
#include <errno.h>
|
||||||
|
#include <fcntl.h>
|
||||||
|
#include <stdio.h>
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <string.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* 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]
|
||||||
|
* If no input file is specified, standard input is read.
|
||||||
|
*
|
||||||
|
* Should be compatible 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;
|
||||||
|
|
||||||
|
static DB *db;
|
||||||
|
static NODE *graph, **cycle_buf, **longest_cycle;
|
||||||
|
static int debug, longest, quiet;
|
||||||
|
|
||||||
|
static void add_arc(char *, char *);
|
||||||
|
static void clear_cycle(void);
|
||||||
|
static int find_cycle(NODE *, NODE *, int, int);
|
||||||
|
static NODE *get_node(char *);
|
||||||
|
static void *grow_buf(void *, int);
|
||||||
|
static void remove_node(NODE *);
|
||||||
|
static void tsort(void);
|
||||||
|
__dead static void usage(void);
|
||||||
|
|
||||||
|
int
|
||||||
|
main(int argc, char *argv[])
|
||||||
|
{
|
||||||
|
BUF *b;
|
||||||
|
int c, n;
|
||||||
|
FILE *fp;
|
||||||
|
int bsize, ch, nused;
|
||||||
|
BUF bufs[2];
|
||||||
|
|
||||||
|
setprogname(argv[0]);
|
||||||
|
|
||||||
|
fp = NULL;
|
||||||
|
while ((ch = getopt(argc, argv, "dlq")) != -1)
|
||||||
|
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();
|
||||||
|
return(0);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* double the size of oldbuf and return a pointer to the new buffer. */
|
||||||
|
static void *
|
||||||
|
grow_buf(void *bp, int size)
|
||||||
|
{
|
||||||
|
void *n;
|
||||||
|
|
||||||
|
if ((n = realloc(bp, (u_int)size)) == NULL)
|
||||||
|
err(1, "realloc");
|
||||||
|
bp = n;
|
||||||
|
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.
|
||||||
|
*/
|
||||||
|
static void
|
||||||
|
add_arc(char *s1, char *s2)
|
||||||
|
{
|
||||||
|
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. */
|
||||||
|
static NODE *
|
||||||
|
get_node(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:
|
||||||
|
(void)memmove(&n, data.data, 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, "malloc");
|
||||||
|
|
||||||
|
n->n_narcs = 0;
|
||||||
|
n->n_arcsize = 0;
|
||||||
|
n->n_arcs = NULL;
|
||||||
|
n->n_refcnt = 0;
|
||||||
|
n->n_flags = 0;
|
||||||
|
(void)memmove(n->n_name, 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.
|
||||||
|
*/
|
||||||
|
static void
|
||||||
|
clear_cycle(void)
|
||||||
|
{
|
||||||
|
NODE *n;
|
||||||
|
|
||||||
|
for (n = graph; n != NULL; n = n->n_next)
|
||||||
|
n->n_flags &= ~NF_NODEST;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* do topological sort on graph */
|
||||||
|
static void
|
||||||
|
tsort(void)
|
||||||
|
{
|
||||||
|
NODE *n, *next;
|
||||||
|
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, "malloc");
|
||||||
|
}
|
||||||
|
for (n = graph; n != NULL; n = n->n_next) {
|
||||||
|
if (!(n->n_flags & NF_ACYCLIC)) {
|
||||||
|
if ((cnt = find_cycle(n, n, 0, 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) */
|
||||||
|
static void
|
||||||
|
remove_node(NODE *n)
|
||||||
|
{
|
||||||
|
NODE **np;
|
||||||
|
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. */
|
||||||
|
static int
|
||||||
|
find_cycle(NODE *from, NODE *to, int longest_len, int depth)
|
||||||
|
{
|
||||||
|
NODE **np;
|
||||||
|
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(longest_cycle, 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);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void
|
||||||
|
usage(void)
|
||||||
|
{
|
||||||
|
(void)fprintf(stderr, "usage: tsort [-lq] [file]\n");
|
||||||
|
exit(1);
|
||||||
|
}
|
||||||
Loading…
Reference in a new issue