1 #include "std.h"
2 #include "dat.h"
3 
4 Attr*
5 addattr(Attr *a, char *fmt, ...)
6 {
7 	char buf[1024];
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[1024], *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 static int
134 hasqueries(Attr *a)
135 {
136 	for(; a; a=a->next)
137 		if(a->type == AttrQuery)
138 			return 1;
139 	return 0;
140 }
141 
142 char *ignored[] = {
143 	"role",
144 };
145 
146 static int
147 ignoreattr(char *s)
148 {
149 	int i;
150 
151 	for(i=0; i<nelem(ignored); i++)
152 		if(strcmp(ignored[i], s)==0)
153 			return 1;
154 	return 0;
155 }
156 
157 static int
158 hasname(Attr *a0, Attr *a1, char *name)
159 {
160 	return _findattr(a0, name) || _findattr(a1, name);
161 }
162 
163 static int
164 hasnameval(Attr *a0, Attr *a1, char *name, char *val)
165 {
166 	Attr *a;
167 
168 	for(a=_findattr(a0, name); a; a=_findattr(a->next, name))
169 		if(strcmp(a->val, val) == 0)
170 			return 1;
171 	for(a=_findattr(a1, name); a; a=_findattr(a->next, name))
172 		if(strcmp(a->val, val) == 0)
173 			return 1;
174 	return 0;
175 }
176 
177 int
178 matchattr(Attr *pat, Attr *a0, Attr *a1)
179 {
180 	int type;
181 
182 	for(; pat; pat=pat->next){
183 		type = pat->type;
184 		if(ignoreattr(pat->name))
185 			type = AttrDefault;
186 		switch(type){
187 		case AttrQuery:		/* name=something be present */
188 			if(!hasname(a0, a1, pat->name))
189 				return 0;
190 			break;
191 		case AttrNameval:	/* name=val must be present */
192 			if(!hasnameval(a0, a1, pat->name, pat->val))
193 				return 0;
194 			break;
195 		case AttrDefault:	/* name=val must be present if name=anything is present */
196 			if(hasname(a0, a1, pat->name) && !hasnameval(a0, a1, pat->name, pat->val))
197 				return 0;
198 			break;
199 		}
200 	}
201 	return 1;		
202 }
203 
204 Attr*
205 parseattrfmtv(char *fmt, va_list arg)
206 {
207 	char *s;
208 	Attr *a;
209 
210 	s = vsmprint(fmt, arg);
211 	if(s == nil)
212 		sysfatal("vsmprint: out of memory");
213 	a = parseattr(s);
214 	free(s);
215 	return a;
216 }
217 
218 Attr*
219 parseattrfmt(char *fmt, ...)
220 {
221 	va_list arg;
222 	Attr *a;
223 
224 	va_start(arg, fmt);
225 	a = parseattrfmtv(fmt, arg);
226 	va_end(arg);
227 	return a;
228 }