1 #include <u.h>
2 #include <libc.h>
3 #include <stdio.h>
4 #include "cpp.h"
5
6 /*
7 * A hideset is a null-terminated array of Nlist pointers.
8 * They are referred to by indices in the hidesets array.
9 * Hideset 0 is empty.
10 */
11
12 #define HSSIZ 32
13 typedef Nlist **Hideset;
14 Hideset *hidesets;
15 int nhidesets = 0;
16 int maxhidesets = 3;
17 int inserths(Hideset, Hideset, Nlist *);
18
19 /*
20 * Test for membership in a hideset
21 */
22 int
checkhideset(int hs,Nlist * np)23 checkhideset(int hs, Nlist *np)
24 {
25 Hideset hsp;
26
27 if (hs>=nhidesets)
28 abort();
29 for (hsp = hidesets[hs]; *hsp; hsp++) {
30 if (*hsp == np)
31 return 1;
32 }
33 return 0;
34 }
35
36 /*
37 * Return the (possibly new) hideset obtained by adding np to hs.
38 */
39 int
newhideset(int hs,Nlist * np)40 newhideset(int hs, Nlist *np)
41 {
42 int i, len;
43 Nlist *nhs[HSSIZ+3];
44 Hideset hs1, hs2;
45
46 len = inserths(nhs, hidesets[hs], np);
47 for (i=0; i<nhidesets; i++) {
48 for (hs1=nhs, hs2=hidesets[i]; *hs1==*hs2; hs1++, hs2++)
49 if (*hs1 == NULL)
50 return i;
51 }
52 if (len>=HSSIZ)
53 return hs;
54 if (nhidesets >= maxhidesets) {
55 maxhidesets = 3*maxhidesets/2+1;
56 hidesets = (Hideset *)realloc(hidesets, (sizeof (Hideset *))*maxhidesets);
57 }
58 hs1 = (Hideset)domalloc(len*sizeof(Hideset));
59 memmove(hs1, nhs, len*sizeof(Hideset));
60 hidesets[nhidesets] = hs1;
61 return nhidesets++;
62 }
63
64 int
inserths(Hideset dhs,Hideset shs,Nlist * np)65 inserths(Hideset dhs, Hideset shs, Nlist *np)
66 {
67 Hideset odhs = dhs;
68
69 while (*shs && *shs < np)
70 *dhs++ = *shs++;
71 if (*shs != np)
72 *dhs++ = np;
73 do {
74 *dhs++ = *shs;
75 } while (*shs++);
76 return dhs - odhs;
77 }
78
79 /*
80 * Hideset union
81 */
82 int
unionhideset(int hs1,int hs2)83 unionhideset(int hs1, int hs2)
84 {
85 Hideset hp;
86
87 for (hp = hidesets[hs2]; *hp; hp++)
88 hs1 = newhideset(hs1, *hp);
89 return hs1;
90 }
91
92 void
iniths(void)93 iniths(void)
94 {
95 hidesets = (Hideset *)domalloc(maxhidesets*sizeof(Hideset *));
96 hidesets[0] = (Hideset)domalloc(sizeof(Hideset));
97 *hidesets[0] = NULL;
98 nhidesets++;
99 }
100
101 void
prhideset(int hs)102 prhideset(int hs)
103 {
104 Hideset np;
105
106 for (np = hidesets[hs]; *np; np++) {
107 fprintf(stderr, (char*)(*np)->name, (*np)->len);
108 fprintf(stderr, " ", 1);
109 }
110 }
111