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[ld] Add 3rd pass

This pass updates the base address of every section that is going
to be linked.

--- a/include/scc/scc/mach.h

+++ b/include/scc/scc/mach.h

@@ -18,17 +18,19 @@

 struct objsect {

 	char *name;

+	int id;

 	int type;

-	unsigned flags;

-	long offset;

 	int align;

-	unsigned long long size;

+	unsigned flags;

+	long seek;

+	unsigned long long size, base;

 	Objsect *next;

 };

 struct objsym {

-	char type;

 	char *name;

+	int type;

+	int sect;

 	unsigned long long size;

 	unsigned long long value;

 	Objsym *next, *hash;

--- a/src/cmd/Makefile

+++ b/src/cmd/Makefile

@@ -7,7 +7,6 @@

          $(BINDIR)/strip \

          $(BINDIR)/size \

          $(BINDIR)/ar \

-         $(BINDIR)/ld \

          $(BINDIR)/ranlib \

          $(BINDIR)/objdump \

          $(BINDIR)/objcopy \

--- a/src/cmd/ld/pass1.c

+++ b/src/cmd/ld/pass1.c

@@ -13,7 +13,7 @@

 Objlst *objhead, *objlast;

 static void

-loadobj(Obj *obj, FILE *fp)

+addobj(Obj *obj, FILE *fp)

 {

 	int n;

 	Objlst *lst;

@@ -70,7 +70,7 @@

 	 * some symbol needed.

 	 */

 	if (!inlib || defasym(obj)) {

-		loadobj(obj, fp);

+		addobj(obj, fp);

 		return;

 	}

@@ -80,9 +80,9 @@

 }

 static void

-loadlib(FILE *fp)

+addlib(FILE *fp)

 {

-	int t, loaded;

+	int t, added;

 	long n;

 	Objsymdef *def, *dp;

 	Symbol *sym;

@@ -92,9 +92,9 @@

 		return;

 	}

-	loaded = 1;

-	while (moreundef() && loaded) {

-		loaded = 0;

+	added = 1;

+	while (moreundef() && added) {

+		added = 0;

 		for (dp = def; dp; dp = dp->next) {

 			sym = lookup(dp->name, NOINSTALL);

 			if (!sym || sym->def)

@@ -116,7 +116,7 @@

 			}

 			newobject(fp, t, OUTLIB);

-			loaded = 1;

+			added = 1;

 		}

 	}

 clean:

@@ -137,7 +137,7 @@

 	if (*nmemb++ == 0) {

 		if (!strncmp(name, "/", SARNAM) ||

 		    !strncmp(name, "__.SYMDEF", SARNAM)) {

-			loadlib(fp);

+			addlib(fp);

 			return 0;

 		}

 	}

--- a/src/cmd/ld/pass3.c

+++ b/src/cmd/ld/pass3.c

@@ -1,3 +1,4 @@

+#include <ctype.h>

 #include <stdio.h>

 #include <stdlib.h>

@@ -5,8 +6,35 @@

 #include "ld.h"

+static void

+rebase(Obj *obj)

+{

+	Symbol *aux;

+	Objsym *sym;

+

+	for (sym = obj->syms; sym; sym = sym->next) {

+		switch (toupper(sym->type)) {

+		case 'T':

+		case 'D':

+		case 'B':

+			aux = lookup(sym->name, NOINSTALL);

+			aux->value += obj->secs[sym->sect].base;

+		case 't':

+		case 'd':

+		case 'b':

+			sym->value += obj->secs[sym->sect].base;

+		case 'N':

+		case 'U':

+		case '?':

+			break;

+		default:

+			abort();

+		}

+	}

+}

+

 /*

- * relocate the sections

+ * rebase all the sections

  */

 void

 pass3(int argc, char *argv[])

@@ -14,21 +42,34 @@

 	Obj *obj;

 	Objlst *lst;

 	Objsect *sp;

-	unsigned long long text, data, bss;

+	unsigned long long *base, text, data, bss;

-	textbase = text = 0;

-	database = data = textsiz+3 & ~3;

-	bssbase = bss = data+datasiz+3 & ~3;

+	/*

+	 * TODO: deal with page aligment

+	 */

+	textbase = text = 0x100;

+	database = data = textsiz;

+	bssbase = bss = data+datasiz;

 	for (lst = objhead; lst; lst = lst->next) {

-		for (sp = lst->obj->secs; sp; sp = sp->next) {

+		obj = lst->obj;

+		for (sp = obj->secs; sp; sp = sp->next) {

 			switch (sp->type) {

 			case 'T':

+				base = &text;

+				break;

 			case 'D':

+				base = &data;

+				break;

 			case 'B':

+				base = &bss;

+				break;

 			default:

 				abort();

 			}

+			sp->base = *base;

+			*base += sp->size;

 		}

+		rebase(obj);

 	}

 }

--- a/src/libmach/coff32/coff32getsect.c

+++ b/src/libmach/coff32/coff32getsect.c

@@ -64,7 +64,8 @@

 			sflags &= ~SLOAD;

 		sp->name = scn->s_name;

-		sp->offset = scn->s_scnptr;

+		sp->id = i;

+		sp->seek = scn->s_scnptr;

 		sp->size = scn->s_size;

 		sp->type = type;

 		sp->flags = sflags;

--- a/src/libmach/coff32/coff32getsyms.c

+++ b/src/libmach/coff32/coff32getsyms.c

@@ -84,6 +84,7 @@

 		sym->type = t;

 		sym->value = ent->n_value;

 		sym->size = (sym->type == 'C') ? ent->n_value : 0;

+		sym->sect = ent->n_scnum-1;

 	}

 	return i;