Initial revision

src/cmd/mk/graph.c

@@ -0,0 +1,279 @@
+#include	"mk.h"
+
+static Node *applyrules(char *, char *);
+static void togo(Node *);
+static int vacuous(Node *);
+static Node *newnode(char *);
+static void trace(char *, Arc *);
+static void cyclechk(Node *);
+static void ambiguous(Node *);
+static void attribute(Node *);
+
+Node *
+graph(char *target)
+{
+	Node *node;
+	char *cnt;
+
+	cnt = rulecnt();
+	node = applyrules(target, cnt);
+	free(cnt);
+	cyclechk(node);
+	node->flags |= PROBABLE;	/* make sure it doesn't get deleted */
+	vacuous(node);
+	ambiguous(node);
+	attribute(node);
+	return(node);
+}
+
+static Node *
+applyrules(char *target, char *cnt)
+{
+	Symtab *sym;
+	Node *node;
+	Rule *r;
+	Arc head, *a = &head;
+	Word *w;
+	char stem[NAMEBLOCK], buf[NAMEBLOCK];
+	Resub rmatch[NREGEXP];
+
+/*	print("applyrules(%lux='%s')\n", target, target);*//**/
+	sym = symlook(target, S_NODE, 0);
+	if(sym)
+		return (Node *)(sym->value);
+	target = strdup(target);
+	node = newnode(target);
+	head.n = 0;
+	head.next = 0;
+	sym = symlook(target, S_TARGET, 0);
+	memset((char*)rmatch, 0, sizeof(rmatch));
+	for(r = sym? (Rule *)(sym->value):0; r; r = r->chain){
+		if(r->attr&META) continue;
+		if(strcmp(target, r->target)) continue;
+		if((!r->recipe || !*r->recipe) && (!r->tail || !r->tail->s || !*r->tail->s)) continue;	/* no effect; ignore */
+		if(cnt[r->rule] >= nreps) continue;
+		cnt[r->rule]++;
+		node->flags |= PROBABLE;
+
+/*		if(r->attr&VIR)
+ *			node->flags |= VIRTUAL;
+ *		if(r->attr&NOREC)
+ *			node->flags |= NORECIPE;
+ *		if(r->attr&DEL)
+ *			node->flags |= DELETE;
+ */
+		if(!r->tail || !r->tail->s || !*r->tail->s) {
+			a->next = newarc((Node *)0, r, "", rmatch);
+			a = a->next;
+		} else
+			for(w = r->tail; w; w = w->next){
+				a->next = newarc(applyrules(w->s, cnt), r, "", rmatch);
+				a = a->next;
+		}
+		cnt[r->rule]--;
+		head.n = node;
+	}
+	for(r = metarules; r; r = r->next){
+		if((!r->recipe || !*r->recipe) && (!r->tail || !r->tail->s || !*r->tail->s)) continue;	/* no effect; ignore */
+		if ((r->attr&NOVIRT) && a != &head && (a->r->attr&VIR))
+			continue;
+		if(r->attr&REGEXP){
+			stem[0] = 0;
+			patrule = r;
+			memset((char*)rmatch, 0, sizeof(rmatch));
+			if(regexec(r->pat, node->name, rmatch, NREGEXP) == 0)
+				continue;
+		} else {
+			if(!match(node->name, r->target, stem)) continue;
+		}
+		if(cnt[r->rule] >= nreps) continue;
+		cnt[r->rule]++;
+
+/*		if(r->attr&VIR)
+ *			node->flags |= VIRTUAL;
+ *		if(r->attr&NOREC)
+ *			node->flags |= NORECIPE;
+ *		if(r->attr&DEL)
+ *			node->flags |= DELETE;
+ */
+
+		if(!r->tail || !r->tail->s || !*r->tail->s) {
+			a->next = newarc((Node *)0, r, stem, rmatch);
+			a = a->next;
+		} else
+			for(w = r->tail; w; w = w->next){
+				if(r->attr&REGEXP)
+					regsub(w->s, buf, sizeof buf, rmatch, NREGEXP);
+				else
+					subst(stem, w->s, buf);
+				a->next = newarc(applyrules(buf, cnt), r, stem, rmatch);
+				a = a->next;
+			}
+		cnt[r->rule]--;
+	}
+	a->next = node->prereqs;
+	node->prereqs = head.next;
+	return(node);
+}
+
+static void
+togo(Node *node)
+{
+	Arc *la, *a;
+
+	/* delete them now */
+	la = 0;
+	for(a = node->prereqs; a; la = a, a = a->next)
+		if(a->flag&TOGO){
+			if(a == node->prereqs)
+				node->prereqs = a->next;
+			else
+				la->next = a->next, a = la;
+		}
+}
+
+static int
+vacuous(Node *node)
+{
+	Arc *la, *a;
+	int vac = !(node->flags&PROBABLE);
+
+	if(node->flags&READY)
+		return(node->flags&VACUOUS);
+	node->flags |= READY;
+	for(a = node->prereqs; a; a = a->next)
+		if(a->n && vacuous(a->n) && (a->r->attr&META))
+			a->flag |= TOGO;
+		else
+			vac = 0;
+	/* if a rule generated arcs that DON'T go; no others from that rule go */
+	for(a = node->prereqs; a; a = a->next)
+		if((a->flag&TOGO) == 0)
+			for(la = node->prereqs; la; la = la->next)
+				if((la->flag&TOGO) && (la->r == a->r)){
+					la->flag &= ~TOGO;
+				}
+	togo(node);
+	if(vac)
+		node->flags |= VACUOUS;
+	return(vac);
+}
+
+static Node *
+newnode(char *name)
+{
+	register Node *node;
+
+	node = (Node *)Malloc(sizeof(Node));
+	symlook(name, S_NODE, (void *)node);
+	node->name = name;
+	node->time = timeof(name, 0);
+	node->prereqs = 0;
+	node->flags = node->time? PROBABLE : 0;
+	node->next = 0;
+	return(node);
+}
+
+void
+dumpn(char *s, Node *n)
+{
+	char buf[1024];
+	Arc *a;
+
+	sprint(buf, "%s   ", (*s == ' ')? s:"");
+	Bprint(&bout, "%s%s@%ld: time=%ld flags=0x%x next=%ld\n",
+		s, n->name, n, n->time, n->flags, n->next);
+	for(a = n->prereqs; a; a = a->next)
+		dumpa(buf, a);
+}
+
+static void
+trace(char *s, Arc *a)
+{
+	fprint(2, "\t%s", s);
+	while(a){
+		fprint(2, " <-(%s:%d)- %s", a->r->file, a->r->line,
+			a->n? a->n->name:"");
+		if(a->n){
+			for(a = a->n->prereqs; a; a = a->next)
+				if(*a->r->recipe) break;
+		} else
+			a = 0;
+	}
+	fprint(2, "\n");
+}
+
+static void
+cyclechk(Node *n)
+{
+	Arc *a;
+
+	if((n->flags&CYCLE) && n->prereqs){
+		fprint(2, "mk: cycle in graph detected at target %s\n", n->name);
+		Exit();
+	}
+	n->flags |= CYCLE;
+	for(a = n->prereqs; a; a = a->next)
+		if(a->n)
+			cyclechk(a->n);
+	n->flags &= ~CYCLE;
+}
+
+static void
+ambiguous(Node *n)
+{
+	Arc *a;
+	Rule *r = 0;
+	Arc *la;
+	int bad = 0;
+
+	la = 0;
+	for(a = n->prereqs; a; a = a->next){
+		if(a->n)
+			ambiguous(a->n);
+		if(*a->r->recipe == 0) continue;
+		if(r == 0)
+			r = a->r, la = a;
+		else{
+			if(r->recipe != a->r->recipe){
+				if((r->attr&META) && !(a->r->attr&META)){
+					la->flag |= TOGO;
+					r = a->r, la = a;
+				} else if(!(r->attr&META) && (a->r->attr&META)){
+					a->flag |= TOGO;
+					continue;
+				}
+			}
+			if(r->recipe != a->r->recipe){
+				if(bad == 0){
+					fprint(2, "mk: ambiguous recipes for %s:\n", n->name);
+					bad = 1;
+					trace(n->name, la);
+				}
+				trace(n->name, a);
+			}
+		}
+	}
+	if(bad)
+		Exit();
+	togo(n);
+}
+
+static void
+attribute(Node *n)
+{
+	register Arc *a;
+
+	for(a = n->prereqs; a; a = a->next){
+		if(a->r->attr&VIR)
+			n->flags |= VIRTUAL;
+		if(a->r->attr&NOREC)
+			n->flags |= NORECIPE;
+		if(a->r->attr&DEL)
+			n->flags |= DELETE;
+		if(a->n)
+			attribute(a->n);
+	}
+	if(n->flags&VIRTUAL)
+		n->time = 0;
+}