ref: c59eb6d117c6dc99bc6e4330d3a9a3453888dee7
dir: /sys/src/cmd/7l/mod.c/
#include "l.h" void readundefs(char *f, int t) { int i, n; Sym *s; Biobuf *b; char *l, buf[256], *fields[64]; if(f == nil) return; b = Bopen(f, OREAD); if(b == nil){ diag("could not open %s: %r", f); errorexit(); } while((l = Brdline(b, '\n')) != nil){ n = Blinelen(b); if(n >= sizeof(buf)){ diag("%s: line too long", f); errorexit(); } memmove(buf, l, n); buf[n-1] = '\0'; n = getfields(buf, fields, nelem(fields), 1, " \t\r\n"); if(n == nelem(fields)){ diag("%s: bad format", f); errorexit(); } for(i = 0; i < n; i++){ s = lookup(fields[i], 0); s->type = SXREF; s->subtype = t; if(t == SIMPORT) nimports++; else nexports++; } } Bterm(b); } void undefsym(Sym *s) { int n; n = imports; if(s->value != 0) diag("value != 0 on SXREF"); if(n >= 1<<Rindex) diag("import index %d out of range", n); s->value = n<<Roffset; s->type = SUNDEF; imports++; } void zerosig(char *sp) { Sym *s; s = lookup(sp, 0); s->sig = 0; } void import(void) { int i; Sym *s; for(i = 0; i < NHASH; i++) for(s = hash[i]; s != S; s = s->link) if(s->sig != 0 && s->type == SXREF && (nimports == 0 || s->subtype == SIMPORT)){ undefsym(s); Bprint(&bso, "IMPORT: %s sig=%lux v=%lld\n", s->name, s->sig, (vlong)s->value); } } void ckoff(Sym *s, long v) { if(v < 0 || v >= 1<<Roffset) diag("relocation offset %ld for %s out of range", v, s->name); } static Prog* newdata(Sym *s, int o, int w, int t) { Prog *p; p = prg(); p->link = datap; datap = p; p->as = ADATA; p->reg = w; p->from.type = D_OREG; p->from.name = t; p->from.sym = s; p->from.offset = o; p->to.type = D_CONST; p->to.name = D_NONE; return p; } void export(void) { int i, j, n, off, nb, sv, ne; Sym *s, *et, *str, **esyms; Prog *p; char buf[NSNAME], *t; n = 0; for(i = 0; i < NHASH; i++) for(s = hash[i]; s != S; s = s->link) if(s->sig != 0 && s->type != SXREF && s->type != SUNDEF && (nexports == 0 || s->subtype == SEXPORT)) n++; esyms = malloc(n*sizeof(Sym*)); ne = n; n = 0; for(i = 0; i < NHASH; i++) for(s = hash[i]; s != S; s = s->link) if(s->sig != 0 && s->type != SXREF && s->type != SUNDEF && (nexports == 0 || s->subtype == SEXPORT)) esyms[n++] = s; for(i = 0; i < ne-1; i++) for(j = i+1; j < ne; j++) if(strcmp(esyms[i]->name, esyms[j]->name) > 0){ s = esyms[i]; esyms[i] = esyms[j]; esyms[j] = s; } nb = 0; off = 0; et = lookup(EXPTAB, 0); if(et->type != 0 && et->type != SXREF) diag("%s already defined", EXPTAB); et->type = SDATA; str = lookup(".string", 0); if(str->type == 0) str->type = SDATA; sv = str->value; for(i = 0; i < ne; i++){ s = esyms[i]; Bprint(&bso, "EXPORT: %s sig=%lux t=%d\n", s->name, s->sig, s->type); /* signature */ p = newdata(et, off, sizeof(long), D_EXTERN); off += sizeof(long); p->to.offset = s->sig; /* address */ p = newdata(et, off, sizeof(long), D_EXTERN); off += sizeof(long); p->to.name = D_EXTERN; p->to.sym = s; /* string */ t = s->name; n = strlen(t)+1; for(;;){ buf[nb++] = *t; sv++; if(nb >= NSNAME){ p = newdata(str, sv-NSNAME, NSNAME, D_STATIC); p->to.type = D_SCONST; p->to.sval = malloc(NSNAME); memmove(p->to.sval, buf, NSNAME); nb = 0; } if(*t++ == 0) break; } /* name */ p = newdata(et, off, sizeof(long), D_EXTERN); off += sizeof(long); p->to.name = D_STATIC; p->to.sym = str; p->to.offset = sv-n; } if(nb > 0){ p = newdata(str, sv-nb, nb, D_STATIC); p->to.type = D_SCONST; p->to.sval = malloc(NSNAME); memmove(p->to.sval, buf, nb); } for(i = 0; i < 3; i++){ newdata(et, off, sizeof(long), D_EXTERN); off += sizeof(long); } et->value = off; if(sv == 0) sv = 1; str->value = sv; exports = ne; free(esyms); }