projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 0fc6e47b KB |
1 | /*- |
| 2 | * Copyright (c) 1980 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * %sccs.include.redist.c% | |
| 1259848a | 6 | */ |
| dfd13e7c | 7 | |
| 72fbef68 | 8 | #ifndef lint |
| 0fc6e47b KB |
9 | static char sccsid[] = "@(#)lookup.c 5.2 (Berkeley) %G%"; |
| 10 | #endif /* not lint */ | |
| dfd13e7c PK |
11 | |
| 12 | #include "whoami.h" | |
| 13 | #include "0.h" | |
| 14 | ||
| 270467f1 KM |
15 | struct nl *disptab[077+1]; |
| 16 | ||
| dfd13e7c PK |
17 | /* |
| 18 | * Lookup is called to | |
| 19 | * find a symbol in the | |
| 20 | * block structure symbol | |
| 21 | * table and returns a pointer to | |
| 22 | * its namelist entry. | |
| 23 | */ | |
| 24 | struct nl * | |
| 25 | lookup(s) | |
| 26 | register char *s; | |
| 27 | { | |
| 28 | register struct nl *p; | |
| 72fbef68 | 29 | register struct udinfo; |
| dfd13e7c PK |
30 | |
| 31 | if (s == NIL) { | |
| 32 | nocascade(); | |
| 72fbef68 | 33 | return (NLNIL); |
| dfd13e7c PK |
34 | } |
| 35 | p = lookup1(s); | |
| 72fbef68 | 36 | if (p == NLNIL) { |
| dfd13e7c | 37 | derror("%s is undefined", s); |
| 72fbef68 | 38 | return (NLNIL); |
| dfd13e7c PK |
39 | } |
| 40 | if (p->class == FVAR) { | |
| 41 | p = p->chain; | |
| 42 | bn--; | |
| 43 | } | |
| 44 | return (p); | |
| 45 | } | |
| 46 | ||
| 47 | #ifndef PI0 | |
| 48 | int flagwas; | |
| 49 | #endif | |
| 50 | /* | |
| 51 | * Lookup1 is an internal lookup. | |
| 52 | * It is not an error to call lookup1 | |
| 53 | * if the symbol is not defined. Also | |
| 54 | * lookup1 will return FVARs while | |
| 55 | * lookup never will, thus asgnop | |
| 56 | * calls it when it thinks you are | |
| 57 | * assigning to the function variable. | |
| 58 | */ | |
| 59 | ||
| 60 | struct nl * | |
| 61 | lookup1(s) | |
| 62 | register char *s; | |
| 63 | { | |
| 64 | register struct nl *p; | |
| 65 | #ifndef PI0 | |
| 66 | register struct nl *q; | |
| 67 | #endif | |
| 68 | register int i; | |
| 69 | ||
| 70 | if (s == NIL) | |
| 72fbef68 | 71 | return (NLNIL); |
| dfd13e7c PK |
72 | bn = cbn; |
| 73 | #ifndef PI0 | |
| 74 | /* | |
| 75 | * We first check the field names | |
| 76 | * of the currently active with | |
| 77 | * statements (expensive since they | |
| 78 | * are not hashed). | |
| 79 | */ | |
| 72fbef68 | 80 | for (p = withlist; p != NLNIL; p = p->nl_next) { |
| dfd13e7c | 81 | q = p->type; |
| 72fbef68 | 82 | if (q == NLNIL) |
| dfd13e7c PK |
83 | continue; |
| 84 | if (reclook(q, s) != NIL) | |
| 85 | /* | |
| 86 | * Return the WITHPTR, lvalue understands. | |
| 87 | */ | |
| 88 | return (p); | |
| 89 | } | |
| 90 | #endif | |
| 91 | /* | |
| 92 | * Symbol table is a 64 way hash | |
| 93 | * on the low bits of the character | |
| 94 | * pointer value. (Simple, but effective) | |
| 95 | */ | |
| 96 | i = (int) s & 077; | |
| 72fbef68 | 97 | for (p = disptab[i]; p != NLNIL; p = p->nl_next) |
| dfd13e7c PK |
98 | if (p->symbol == s && p->class != FIELD && p->class != BADUSE) { |
| 99 | bn = (p->nl_block & 037); | |
| 100 | #ifndef PI0 | |
| 101 | flagwas = p->nl_flags; | |
| 102 | p->nl_flags |= NUSED; | |
| 103 | #endif | |
| 104 | return (p); | |
| 105 | } | |
| 72fbef68 | 106 | return (NLNIL); |
| dfd13e7c PK |
107 | } |
| 108 | ||
| 109 | #ifndef PI01 | |
| 110 | nlfund(sp) | |
| 111 | char *sp; | |
| 112 | { | |
| 113 | register struct nl *p; | |
| 114 | register int i; | |
| 115 | ||
| 116 | i = (int) sp & 077; | |
| 72fbef68 | 117 | for (p = disptab[i]; p != NLNIL; p = p->nl_next) |
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118 | if (p->symbol == sp && (p->nl_block & 037) == 0) |
| 119 | return (nloff(p)); | |
| 120 | return (0); | |
| 121 | } | |
| 122 | #endif |