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[as/coff32] Calculate correct address for symbols

The address of every symbol depends of the relative address of
the section, and it means that we have to calculate the size
of the section before calculating the address of the symbol,
but we have to keep in mind tha the size was already increased.

--- a/ld/coff32.c

+++ b/ld/coff32.c

@@ -95,21 +95,30 @@

 	unsigned char buff[SCNHSZ];

 	SCNHDR *scn, *p;

 	FILHDR *hdr;

-	Symbol *sym;

+	Symbol *sym, **sec;

 	hdr = obj->filhdr;

 	nsec = hdr->f_nscns;

+

 	if (nsec > SIZE_MAX / sizeof(*scn))

 		return -1;

-	if ((scn = malloc(nsec * sizeof(*scn))) == NULL)

+	if (nsec > SIZE_MAX / sizeof(Symbol *))

 		return -1;

+	scn = malloc(nsec * sizeof(*scn));

+	sec = malloc(nsec * sizeof(Symbol *));

+	if (!scn || !sec)

+		outmem();

+	obj->sections = sec;

+	obj->scnhdr = scn;

+

 	if (fseek(obj->fp, off, SEEK_SET) == EOF)

 		return -1;

 	a = obj->align - 1;

-	for (p = scn; p < &scn[nsec]; ++p) {

+	for (i = 0; i < nsec; ++i) {

+		p = &scn[i];

 		if (fread(buff, SCNHSZ, 1, obj->fp) != 1)

 			return -1;

 		getscn(obj, buff, p);

@@ -123,8 +132,9 @@

 			exit(EXIT_FAILURE);

 		}

 		sym->size += p->s_size;

+		obj->sections[i] = sym;

+		

 	}

-	obj->scnhdr = scn;

 	return 0;

 }

@@ -216,7 +226,9 @@

 getval(Obj *obj, SYMENT *ent)

 {

 	FILHDR *hdr = obj->filhdr;;

-	SCNHDR *scn = obj->scnhdr;

+	SCNHDR *scn;

+	Symbol *sym;

+	unsigned n;

 	if (ent->n_scnum > hdr->f_nscns) {

 		fprintf(stderr,

@@ -226,13 +238,13 @@

 		exit(EXIT_FAILURE);

 	}

-	scn = &scn[ent->n_scnum-1];

+	n = ent->n_scnum-1;

+	scn = obj->scnhdr;

+	scn = &scn[n];

+	sym = obj->sections[n];

-	/*

-	 * TODO: We have to add the composed size of the segment minus

-	 * the size of the fragment

-	 */

-	return ent->n_value - scn->s_size;

+

+	return ent->n_value + (sym->size - scn->s_size);

 }

 static int

@@ -276,10 +288,13 @@

 		type = typeof(obj, &ent);

 		sym = lookup(name);

+		if (ent.n_scnum <= 0)

+			continue;

+

 		switch (sym->type) {

 		case 'U':

 			sym->type = type;

-			sym->value = ent.n_value;

+			sym->value = getval(obj, &ent);

 			if (type == 'C')

 				sym->size = ent.n_value;

 			break;

@@ -292,7 +307,7 @@

 				break;

 			default:

 				sym->type = type;

-				sym->value = ent.n_value;

+				sym->value = getval(obj, &ent);

 				break;

 			}

 			break;

@@ -328,7 +343,6 @@

 	getfhdr(obj, buff, hdr);

 	obj->filhdr = hdr;

-	/* TODO: Check overflow */

 	stroff = pos + hdr->f_symptr + hdr->f_nsyms*SYMESZ;

 	symoff = pos + hdr->f_symptr;

 	secoff = pos + FILHSZ + hdr->f_opthdr;

--- a/ld/ld.h

+++ b/ld/ld.h

@@ -7,14 +7,20 @@

 	char *fname;

 	char *member;

 	FILE *fp;

+	Fmt *fmt;

+

 	void *filhdr;

 	void *scnhdr;

+

 	Symbol **symbols;

+	Symbol **sections;

+

 	char *strtbl;

 	size_t strsiz;

+

 	int (*unpack)(unsigned char *, char *, ...);

 	int align;

-	Fmt *fmt;

+

 	struct obj *next;

 };