1 #include "std.h"
2 #include "dat.h"
3 
4 Attr*
5 addattr(Attr *a, char *fmt, ...)
6 {
7 	char buf[8192];
8 	va_list arg;
9 	Attr *b;
10 
11 	va_start(arg, fmt);
12 	vseprint(buf, buf+sizeof buf, fmt, arg);
13 	va_end(arg);
14 	b = _parseattr(buf);
15 	a = addattrs(a, b);
16 	setmalloctag(a, getcallerpc(&a));
17 	_freeattr(b);
18 	return a;
19 }
20 
21 /*
22  *  add attributes in list b to list a.  If any attributes are in
23  *  both lists, replace those in a by those in b.
24  */
25 Attr*
26 addattrs(Attr *a, Attr *b)
27 {
28 	int found;
29 	Attr **l, *aa;
30 
31 	for(; b; b=b->next){
32 		switch(b->type){
33 		case AttrNameval:
34 			for(l=&a; *l; ){
35 				if(strcmp((*l)->name, b->name) != 0){
36 					l=&(*l)->next;
37 					continue;
38 				}
39 				aa = *l;
40 				*l = aa->next;
41 				aa->next = nil;
42 				freeattr(aa);
43 			}
44 			*l = mkattr(AttrNameval, b->name, b->val, nil);
45 			break;
46 		case AttrQuery:
47 			found = 0;
48 			for(l=&a; *l; l=&(*l)->next)
49 				if((*l)->type==AttrNameval && strcmp((*l)->name, b->name) == 0)
50 					found++;
51 			if(!found)
52 				*l = mkattr(AttrQuery, b->name, b->val, nil);
53 			break;
54 		}
55 	}
56 	return a;		
57 }
58 
59 void
60 setmalloctaghere(void *v)
61 {
62 	setmalloctag(v, getcallerpc(&v));
63 }
64 
65 Attr*
66 sortattr(Attr *a)
67 {
68 	int i;
69 	Attr *anext, *a0, *a1, **l;
70 
71 	if(a == nil || a->next == nil)
72 		return a;
73 
74 	/* cut list in halves */
75 	a0 = nil;
76 	a1 = nil;
77 	i = 0;
78 	for(; a; a=anext){
79 		anext = a->next;
80 		if(i++%2){
81 			a->next = a0;
82 			a0 = a;
83 		}else{
84 			a->next = a1;
85 			a1 = a;
86 		}
87 	}
88 
89 	/* sort */
90 	a0 = sortattr(a0);
91 	a1 = sortattr(a1);
92 
93 	/* merge */
94 	l = &a;
95 	while(a0 || a1){
96 		if(a1==nil){
97 			anext = a0;
98 			a0 = a0->next;
99 		}else if(a0==nil){
100 			anext = a1;
101 			a1 = a1->next;
102 		}else if(strcmp(a0->name, a1->name) < 0){
103 			anext = a0;
104 			a0 = a0->next;
105 		}else{
106 			anext = a1;
107 			a1 = a1->next;
108 		}
109 		*l = anext;
110 		l = &(*l)->next;
111 	}
112 	*l = nil;
113 	return a;
114 }
115 
116 int
117 attrnamefmt(Fmt *fmt)
118 {
119 	char *b, buf[8192], *ebuf;
120 	Attr *a;
121 
122 	ebuf = buf+sizeof buf;
123 	b = buf;
124 	strcpy(buf, " ");
125 	for(a=va_arg(fmt->args, Attr*); a; a=a->next){
126 		if(a->name == nil)
127 			continue;
128 		b = seprint(b, ebuf, " %q?", a->name);
129 	}
130 	return fmtstrcpy(fmt, buf+1);
131 }
132 
133 /*
134 static int
135 hasqueries(Attr *a)
136 {
137 	for(; a; a=a->next)
138 		if(a->type == AttrQuery)
139 			return 1;
140 	return 0;
141 }
142 */
143 
144 char *ignored[] = {
145 	"role",
146 	"disabled"
147 };
148 
149 static int
150 ignoreattr(char *s)
151 {
152 	int i;
153 
154 	for(i=0; i<nelem(ignored); i++)
155 		if(strcmp(ignored[i], s)==0)
156 			return 1;
157 	return 0;
158 }
159 
160 static int
161 hasname(Attr *a0, Attr *a1, char *name)
162 {
163 	return _findattr(a0, name) || _findattr(a1, name);
164 }
165 
166 static int
167 hasnameval(Attr *a0, Attr *a1, char *name, char *val)
168 {
169 	Attr *a;
170 
171 	for(a=_findattr(a0, name); a; a=_findattr(a->next, name))
172 		if(strcmp(a->val, val) == 0)
173 			return 1;
174 	for(a=_findattr(a1, name); a; a=_findattr(a->next, name))
175 		if(strcmp(a->val, val) == 0)
176 			return 1;
177 	return 0;
178 }
179 
180 int
181 matchattr(Attr *pat, Attr *a0, Attr *a1)
182 {
183 	int type;
184 
185 	for(; pat; pat=pat->next){
186 		type = pat->type;
187 		if(ignoreattr(pat->name))
188 			type = AttrDefault;
189 		switch(type){
190 		case AttrQuery:		/* name=something be present */
191 			if(!hasname(a0, a1, pat->name))
192 				return 0;
193 			break;
194 		case AttrNameval:	/* name=val must be present */
195 			if(!hasnameval(a0, a1, pat->name, pat->val))
196 				return 0;
197 			break;
198 		case AttrDefault:	/* name=val must be present if name=anything is present */
199 			if(hasname(a0, a1, pat->name) && !hasnameval(a0, a1, pat->name, pat->val))
200 				return 0;
201 			break;
202 		}
203 	}
204 	return 1;		
205 }
206 
207 Attr*
208 parseattrfmtv(char *fmt, va_list arg)
209 {
210 	char *s;
211 	Attr *a;
212 
213 	s = vsmprint(fmt, arg);
214 	if(s == nil)
215 		sysfatal("vsmprint: out of memory");
216 	a = parseattr(s);
217 	free(s);
218 	return a;
219 }
220 
221 Attr*
222 parseattrfmt(char *fmt, ...)
223 {
224 	va_list arg;
225 	Attr *a;
226 
227 	va_start(arg, fmt);
228 	a = parseattrfmtv(fmt, arg);
229 	va_end(arg);
230 	return a;
231 }