projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 505bf312 KB |
1 | /*- |
| 2 | * Copyright (c) 1980 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * %sccs.include.redist.c% | |
| f644bb55 | 6 | */ |
| af72557c | 7 | |
| f644bb55 | 8 | #ifndef lint |
| 505bf312 KB |
9 | static char sccsid[] = "@(#)which.c 5.2 (Berkeley) %G%"; |
| 10 | #endif /* not lint */ | |
| af72557c ML |
11 | |
| 12 | /* | |
| 13 | * Routines to distinguish symbols of the same name. | |
| 14 | */ | |
| 15 | ||
| 16 | #include "defs.h" | |
| 17 | #include "sym.h" | |
| 18 | #include "classes.h" | |
| 19 | #include "symtab.h" | |
| 20 | #include "mappings.h" | |
| 21 | #include "machine.h" | |
| 22 | #include "sym.rep" | |
| 23 | ||
| 24 | /* | |
| 25 | * Figure out the "current" symbol being referred to, | |
| 26 | * this is either the active one or the most visible from the | |
| 27 | * current scope. | |
| 28 | * | |
| 29 | * Fields are purposely ignored; these can be gotten to via "findclass". | |
| 30 | */ | |
| 31 | ||
| 32 | SYM *which(s) | |
| 33 | SYM *s; | |
| 34 | { | |
| 35 | register SYM *p, *t, *f; | |
| 36 | ||
| 37 | if (s == program || isbuiltin(s)) { | |
| 38 | return(s); | |
| 39 | } | |
| 40 | if (!isactive(program)) { | |
| 41 | f = program; | |
| 42 | } else { | |
| 43 | f = whatblock(pc); | |
| 44 | if (f == NIL) { | |
| 45 | panic("no block for addr 0x%x", pc); | |
| 46 | } | |
| 47 | } | |
| 48 | for (p = f; p != NIL; p = p->func) { | |
| 49 | if ((t = findsym(s, p)) != NIL) { | |
| 50 | break; | |
| 51 | } | |
| 52 | } | |
| 53 | if (t == NIL) { | |
| 54 | error("\"%s\" is not known in \"%s\"", s->symbol, f->symbol); | |
| 55 | } | |
| 56 | return(t); | |
| 57 | } | |
| 58 | ||
| 59 | /* | |
| 60 | * Find a (non-field) symbol with name s->symbol belonging to block f. | |
| 61 | * | |
| 62 | * Parameters to the main program are purposely "not found" because | |
| 63 | * pi gives them no type. | |
| 64 | */ | |
| 65 | ||
| 66 | SYM *findsym(s, f) | |
| 67 | SYM *s; | |
| 68 | SYM *f; | |
| 69 | { | |
| 70 | register SYM *t; | |
| 71 | ||
| 72 | if (!isblock(f)) { | |
| 73 | error("%s is not a block", f->symbol); | |
| 74 | } | |
| 75 | for (t = s; t != NIL; t = t->next_sym) { | |
| 76 | if (t->func == f && !(f == program && isparam(t)) && | |
| 77 | t->class != FIELD && streq(t->symbol, s->symbol)) { | |
| 78 | break; | |
| 79 | } | |
| 80 | } | |
| 81 | return(t); | |
| 82 | } | |
| 83 | ||
| 84 | /* | |
| 85 | * Find the symbol which is has the same name and scope as the | |
| 86 | * given symbol but is of the given field. Return NIL if there is none. | |
| 87 | */ | |
| 88 | ||
| 89 | SYM *findclass(s, cl) | |
| 90 | SYM *s; | |
| 91 | char cl; | |
| 92 | { | |
| 93 | register SYM *t; | |
| 94 | ||
| 95 | if (s->class == cl) { | |
| 96 | return(s); | |
| 97 | } | |
| 98 | t = st_lookup(symtab, s->symbol); | |
| 99 | while (t != NIL && (t->class != cl || t->func != s->func || | |
| 100 | !streq(s->symbol, t->symbol))) { | |
| 101 | t = t->next_sym; | |
| 102 | } | |
| 103 | return(t); | |
| 104 | } |