ld: allow seek within write buffer

Reduces number of write+seek's from 88516 to 2080
when linking godoc with 6l.

Thanks to Alex Brainman for pointing out the
many small writes.

R=golang-dev, r, alex.brainman, robert.hencke
CC=golang-dev
https://golang.org/cl/4743043

src/cmd/5l/asm.c

@@ -307,12 +307,12 @@ asmb(void)
 	Bflush(&bso);
 
 	sect = segtext.sect;
-	seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+	cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 	codeblk(sect->vaddr, sect->len);
 
 	/* output read-only data in text segment (rodata, gosymtab and pclntab) */
 	for(sect = sect->next; sect != nil; sect = sect->next) {
-		seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+		cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 		datblk(sect->vaddr, sect->len);
 	}
 
@@ -320,12 +320,12 @@ asmb(void)
 		Bprint(&bso, "%5.2f datblk\n", cputime());
 	Bflush(&bso);
 
-	seek(cout, segdata.fileoff, 0);
+	cseek(segdata.fileoff);
 	datblk(segdata.vaddr, segdata.filelen);
 
 	/* output read-only data in text segment */
 	sect = segtext.sect->next;
-	seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+	cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 	datblk(sect->vaddr, sect->len);
 
 	if(iself) {
@@ -369,13 +369,13 @@ asmb(void)
 			symo = rnd(symo, INITRND);
 			break;
 		}
-		seek(cout, symo, 0);
+		cseek(symo);
 		if(iself) {
 			if(debug['v'])
 			       Bprint(&bso, "%5.2f elfsym\n", cputime());
 			asmelfsym();
 			cflush();
-			ewrite(cout, elfstrdat, elfstrsize);
+			cwrite(elfstrdat, elfstrsize);
 
 			// if(debug['v'])
 			// 	Bprint(&bso, "%5.2f dwarf\n", cputime());
@@ -389,7 +389,7 @@ asmb(void)
 	if(debug['v'])
 		Bprint(&bso, "%5.2f header\n", cputime());
 	Bflush(&bso);
-	seek(cout, 0L, 0);
+	cseek(0L);
 	switch(HEADTYPE) {
 	case Hnoheader:	/* no header */
 		break;
@@ -628,7 +628,7 @@ asmb(void)
 			pph->memsz = pph->filesz;
 		}
 
-		seek(cout, 0, 0);
+		cseek(0);
 		a = 0;
 		a += elfwritehdr();
 		a += elfwritephdrs();
@@ -649,16 +649,6 @@ asmb(void)
 	}
 }
 
-void
-cput(int c)
-{
-	cbp[0] = c;
-	cbp++;
-	cbc--;
-	if(cbc <= 0)
-		cflush();
-}
-
 /*
 void
 cput(int32 c)
@@ -708,19 +698,6 @@ lput(int32 l)
 		cflush();
 }
 
-void
-cflush(void)
-{
-	int n;
-
-	/* no bug if cbc < 0 since obuf(cbuf) followed by ibuf in buf! */
-	n = sizeof(buf.cbuf) - cbc;
-	if(n)
-		ewrite(cout, buf.cbuf, n);
-	cbp = buf.cbuf;
-	cbc = sizeof(buf.cbuf);
-}
-
 void
 nopstat(char *f, Count *c)
 {
@@ -1442,7 +1419,7 @@ if(debug['G']) print("%ux: %s: arm %d\n", (uint32)(p->pc), p->from.sym->name, p-
 	out[5] = o6;
 	return;
 
-#ifdef	NOTDEF
+#ifdef NOTDEF
 	v = p->pc;
 	switch(o->size) {
 	default:

src/cmd/5l/l.h

@@ -264,19 +264,6 @@ enum
 	MINLC	= 4,
 };
 
-EXTERN union
-{
-	struct
-	{
-		uchar	obuf[MAXIO];			/* output buffer */
-		uchar	ibuf[MAXIO];			/* input buffer */
-	} u;
-	char	dbuf[1];
-} buf;
-
-#define	cbuf	u.obuf
-#define	xbuf	u.ibuf
-
 #ifndef COFFCVT
 
 EXTERN	int32	HEADR;			/* length of header */
@@ -286,10 +273,6 @@ EXTERN	int32	INITRND;		/* data round above text location */
 EXTERN	int32	INITTEXT;		/* text location */
 EXTERN	char*	INITENTRY;		/* entry point */
 EXTERN	int32	autosize;
-EXTERN	Biobuf	bso;
-EXTERN	int	cbc;
-EXTERN	uchar*	cbp;
-EXTERN	int	cout;
 EXTERN	Auto*	curauto;
 EXTERN	Auto*	curhist;
 EXTERN	Prog*	curp;

src/cmd/5l/obj.c

@@ -84,7 +84,6 @@ main(int argc, char *argv[])
 	char *p;
 
 	Binit(&bso, 1, OWRITE);
-	cout = -1;
 	listinit();
 	nerrors = 0;
 	outfile = "5.out";

src/cmd/6l/asm.c

@@ -712,12 +712,12 @@ asmb(void)
 	Bflush(&bso);
 
 	sect = segtext.sect;
-	seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+	cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 	codeblk(sect->vaddr, sect->len);
 
 	/* output read-only data in text segment (rodata, gosymtab and pclntab) */
 	for(sect = sect->next; sect != nil; sect = sect->next) {
-		seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+		cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 		datblk(sect->vaddr, sect->len);
 	}
 
@@ -725,7 +725,7 @@ asmb(void)
 		Bprint(&bso, "%5.2f datblk\n", cputime());
 	Bflush(&bso);
 
-	seek(cout, segdata.fileoff, 0);
+	cseek(segdata.fileoff);
 	datblk(segdata.vaddr, segdata.filelen);
 
 	machlink = 0;
@@ -785,14 +785,14 @@ asmb(void)
 			symo = rnd(symo, PEFILEALIGN);
 			break;
 		}
-		seek(cout, symo, 0);
+		cseek(symo);
 		switch(HEADTYPE) {
 		default:
 			if(iself) {
-				seek(cout, symo, 0);
+				cseek(symo);
 				asmelfsym();
 				cflush();
-				ewrite(cout, elfstrdat, elfstrsize);
+				cwrite(elfstrdat, elfstrsize);
 
 				if(debug['v'])
 				       Bprint(&bso, "%5.2f dwarf\n", cputime());
@@ -813,7 +813,7 @@ asmb(void)
 	if(debug['v'])
 		Bprint(&bso, "%5.2f headr\n", cputime());
 	Bflush(&bso);
-	seek(cout, 0L, 0);
+	cseek(0L);
 	switch(HEADTYPE) {
 	default:
 	case Hplan9x32:	/* plan9 */
@@ -1063,7 +1063,7 @@ asmb(void)
 		pph->filesz = eh->phnum * eh->phentsize;
 		pph->memsz = pph->filesz;
 
-		seek(cout, 0, 0);
+		cseek(0);
 		a = 0;
 		a += elfwritehdr();
 		a += elfwritephdrs();
@@ -1079,25 +1079,6 @@ asmb(void)
 	cflush();
 }
 
-void
-cflush(void)
-{
-	int n;
-
-	n = sizeof(buf.cbuf) - cbc;
-	if(n)
-		ewrite(cout, buf.cbuf, n);
-	cbp = buf.cbuf;
-	cbc = sizeof(buf.cbuf);
-}
-
-/* Current position in file */
-vlong
-cpos(void)
-{
-	return seek(cout, 0, 1) + sizeof(buf.cbuf) - cbc;
-}
-
 vlong
 rnd(vlong v, vlong r)
 {

src/cmd/6l/l.h

@@ -46,10 +46,6 @@ enum
 #define	P		((Prog*)0)
 #define	S		((Sym*)0)
 #define	TNAME		(cursym?cursym->name:noname)
-#define	cput(c)\
-	{ *cbp++ = c;\
-	if(--cbc <= 0)\
-		cflush(); }
 
 typedef	struct	Adr	Adr;
 typedef	struct	Prog	Prog;
@@ -286,19 +282,6 @@ enum
 	Maxand	= 10,		/* in -a output width of the byte codes */
 };
 
-EXTERN union
-{
-	struct
-	{
-		char	obuf[MAXIO];			/* output buffer */
-		uchar	ibuf[MAXIO];			/* input buffer */
-	} u;
-	char	dbuf[1];
-} buf;
-
-#define	cbuf	u.obuf
-#define	xbuf	u.ibuf
-
 #pragma	varargck	type	"A"	uint
 #pragma	varargck	type	"D"	Adr*
 #pragma	varargck	type	"I"	uchar*
@@ -313,9 +296,6 @@ EXTERN	int32	INITRND;
 EXTERN	vlong	INITTEXT;
 EXTERN	vlong	INITDAT;
 EXTERN	char*	INITENTRY;		/* entry point */
-EXTERN	Biobuf	bso;
-EXTERN	int	cbc;
-EXTERN	char*	cbp;
 EXTERN	char*	pcstr;
 EXTERN	Auto*	curauto;
 EXTERN	Auto*	curhist;
@@ -376,9 +356,7 @@ vlong	atolwhex(char*);
 Prog*	brchain(Prog*);
 Prog*	brloop(Prog*);
 void	buildop(void);
-void	cflush(void);
 Prog*	copyp(Prog*);
-vlong	cpos(void);
 double	cputime(void);
 void	datblk(int32, int32);
 void	deadcode(void);

src/cmd/6l/obj.c

@@ -80,7 +80,6 @@ main(int argc, char *argv[])
 	int c;
 
 	Binit(&bso, 1, OWRITE);
-	cout = -1;
 	listinit();
 	memset(debug, 0, sizeof(debug));
 	nerrors = 0;

src/cmd/8l/asm.c

@@ -673,12 +673,12 @@ asmb(void)
 	Bflush(&bso);
 
 	sect = segtext.sect;
-	seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+	cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 	codeblk(sect->vaddr, sect->len);
 
 	/* output read-only data in text segment (rodata, gosymtab and pclntab) */
 	for(sect = sect->next; sect != nil; sect = sect->next) {
-		seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
+		cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
 		datblk(sect->vaddr, sect->len);
 	}
 
@@ -686,7 +686,7 @@ asmb(void)
 		Bprint(&bso, "%5.2f datblk\n", cputime());
 	Bflush(&bso);
 
-	seek(cout, segdata.fileoff, 0);
+	cseek(segdata.fileoff);
 	datblk(segdata.vaddr, segdata.filelen);
 
 	machlink = 0;
@@ -743,7 +743,7 @@ asmb(void)
 			symo = rnd(symo, PEFILEALIGN);
 			break;
 		}
-		seek(cout, symo, 0);
+		cseek(symo);
 		switch(HEADTYPE) {
 		default:
 			if(iself) {
@@ -751,7 +751,7 @@ asmb(void)
 				       Bprint(&bso, "%5.2f elfsym\n", cputime());
 				asmelfsym();
 				cflush();
-				ewrite(cout, elfstrdat, elfstrsize);
+				cwrite(elfstrdat, elfstrsize);
 
 				if(debug['v'])
 					Bprint(&bso, "%5.2f dwarf\n", cputime());
@@ -782,7 +782,7 @@ asmb(void)
 	if(debug['v'])
 		Bprint(&bso, "%5.2f headr\n", cputime());
 	Bflush(&bso);
-	seek(cout, 0L, 0);
+	cseek(0L);
 	switch(HEADTYPE) {
 	default:
 		if(iself)
@@ -1138,7 +1138,7 @@ asmb(void)
 			pph->memsz = pph->filesz;
 		}
 
-		seek(cout, 0, 0);
+		cseek(0);
 		a = 0;
 		a += elfwritehdr();
 		a += elfwritephdrs();
@@ -1166,25 +1166,6 @@ s8put(char *n)
 		cput(name[i]);
 }
 
-void
-cflush(void)
-{
-	int n;
-
-	n = sizeof(buf.cbuf) - cbc;
-	if(n)
-		ewrite(cout, buf.cbuf, n);
-	cbp = buf.cbuf;
-	cbc = sizeof(buf.cbuf);
-}
-
-/* Current position in file */
-vlong
-cpos(void)
-{
-	return seek(cout, 0, 1) + sizeof(buf.cbuf) - cbc;
-}
-
 int32
 rnd(int32 v, int32 r)
 {

src/cmd/8l/l.h

@@ -247,19 +247,6 @@ enum
 	Pb		= 0xfe,	/* byte operands */
 };
 
-EXTERN union
-{
-	struct
-	{
-		char	obuf[MAXIO];			/* output buffer */
-		uchar	ibuf[MAXIO];			/* input buffer */
-	} u;
-	char	dbuf[1];
-} buf;
-
-#define	cbuf	u.obuf
-#define	xbuf	u.ibuf
-
 #pragma	varargck	type	"A"	int
 #pragma	varargck	type	"D"	Adr*
 #pragma	varargck	type	"I"	uchar*
@@ -275,10 +262,7 @@ EXTERN	int32	INITRND;
 EXTERN	int32	INITTEXT;
 EXTERN	int32	INITDAT;
 EXTERN	char*	INITENTRY;		/* entry point */
-EXTERN	Biobuf	bso;
 EXTERN	int32	casepc;
-EXTERN	int	cbc;
-EXTERN	char*	cbp;
 EXTERN	char*	pcstr;
 EXTERN	Auto*	curauto;
 EXTERN	Auto*	curhist;

src/cmd/8l/obj.c

@@ -85,7 +85,6 @@ main(int argc, char *argv[])
 	int c;
 
 	Binit(&bso, 1, OWRITE);
-	cout = -1;
 	listinit();
 	memset(debug, 0, sizeof(debug));
 	nerrors = 0;

src/cmd/ld/data.c

@@ -451,7 +451,7 @@ codeblk(int32 addr, int32 size)
 	uchar *q;
 
 	if(debug['a'])
-		Bprint(&bso, "codeblk [%#x,%#x) at offset %#llx\n", addr, addr+size, seek(cout, 0, 1));
+		Bprint(&bso, "codeblk [%#x,%#x) at offset %#llx\n", addr, addr+size, cpos());
 
 	blk(textp, addr, size);
 
@@ -527,7 +527,7 @@ datblk(int32 addr, int32 size)
 	uchar *p, *ep;
 
 	if(debug['a'])
-		Bprint(&bso, "datblk [%#x,%#x) at offset %#llx\n", addr, addr+size, seek(cout, 0, 1));
+		Bprint(&bso, "datblk [%#x,%#x) at offset %#llx\n", addr, addr+size, cpos());
 
 	blk(datap, addr, size);
 

src/cmd/ld/dwarf.c

@@ -1816,15 +1816,13 @@ flushunit(DWDie *dwinfo, vlong pc, vlong unitstart, int32 header_length)
 		cput(0);  // start extended opcode
 		uleb128put(1);
 		cput(DW_LNE_end_sequence);
-		cflush();
 
 		here = cpos();
-		seek(cout, unitstart, 0);
+		cseek(unitstart);
 		LPUT(here - unitstart - sizeof(int32));	 // unit_length
 		WPUT(3);  // dwarf version
 		LPUT(header_length); // header length starting here
-		cflush();
-		seek(cout, here, 0);
+		cseek(here);
 	}
 }
 
@@ -2105,17 +2103,14 @@ writeframes(void)
 		pad = rnd(fdesize, PtrSize) - fdesize;
 		strnput("", pad);
 		fdesize += pad;
-		cflush();
 
 		// Emit the FDE header for real, Section 6.4.1.
-		seek(cout, fdeo, 0);
+		cseek(fdeo);
 		LPUT(fdesize);
 		LPUT(0);
 		addrput(p->pc);
 		addrput(s->size);
-
-		cflush();
-		seek(cout, fdeo + 4 + fdesize, 0);
+		cseek(fdeo + 4 + fdesize);
 	}
 
 	cflush();
@@ -2151,14 +2146,12 @@ writeinfo(void)
 
 		putdie(compunit);
 
-		cflush();
 		here = cpos();
-		seek(cout, unitstart, 0);
+		cseek(unitstart);
 		LPUT(here - unitstart - 4);	// exclude the length field.
-		cflush();
-		seek(cout, here, 0);
+		cseek(here);
 	}
-
+	cflush();
 }
 
 /*
@@ -2213,12 +2206,10 @@ writepub(int (*ispub)(DWDie*))
 		}
 		LPUT(0);
 
-		cflush();
 		here = cpos();
-		seek(cout, sectionstart, 0);
+		cseek(sectionstart);
 		LPUT(here - sectionstart - 4);	// exclude the length field.
-		cflush();
-		seek(cout, here, 0);
+		cseek(here);
 
 	}
 
@@ -2358,7 +2349,7 @@ dwarfemitdebugsections(void)
 	if (fwdcount > 0) {
 		if (debug['v'])
 			Bprint(&bso, "%5.2f dwarf pass 2.\n", cputime());
-		seek(cout, infoo, 0);
+		cseek(infoo);
 		writeinfo();
 		if (fwdcount > 0) {
 			diag("dwarf: unresolved references after first dwarf info pass");

src/cmd/ld/elf.c

@@ -313,8 +313,8 @@ elfwriteinterp(void)
 		return 0;
 
 	n = strlen(interp)+1;
-	seek(cout, ELFRESERVE-n, 0);
-	ewrite(cout, interp, n);
+	cseek(ELFRESERVE-n);
+	cwrite(interp, n);
 	return n;
 }
 

src/cmd/ld/lib.c

@@ -41,7 +41,7 @@ char	symname[]	= SYMDEF;
 char	pkgname[]	= "__.PKGDEF";
 char*	libdir[16];
 int	nlibdir = 0;
-int	cout = -1;
+static int	cout = -1;
 
 char*	goroot;
 char*	goarch;
@@ -937,15 +937,6 @@ addsection(Segment *seg, char *name, int rwx)
 	return sect;
 }
 
-void
-ewrite(int fd, void *buf, int n)
-{
-	if(write(fd, buf, n) < 0) {
-		diag("write error: %r");
-		errorexit();
-	}
-}
-
 void
 pclntab(void)
 {
@@ -1359,3 +1350,71 @@ Yconv(Fmt *fp)
 
 	return 0;
 }
+
+vlong coutpos;
+
+void
+cflush(void)
+{
+	int n;
+
+	if(cbpmax < cbp)
+		cbpmax = cbp;
+	n = cbpmax - buf.cbuf;
+	if(n) {
+		if(write(cout, buf.cbuf, n) != n) {
+			diag("write error: %r");
+			errorexit();
+		}
+		coutpos += n;
+	}
+	cbp = buf.cbuf;
+	cbc = sizeof(buf.cbuf);
+	cbpmax = cbp;
+}
+
+vlong
+cpos(void)
+{
+	return coutpos + cbp - buf.cbuf;
+}
+
+void
+cseek(vlong p)
+{
+	vlong start;
+	int delta;
+
+	if(cbpmax < cbp)
+		cbpmax = cbp;
+	start = coutpos;
+	if(start <= p && p <= start+(cbpmax - buf.cbuf)) {
+//print("cseek %lld in [%lld,%lld] (%lld)\n", p, start, start+sizeof(buf.cbuf), cpos());
+		delta = p - (start + cbp - buf.cbuf);
+		cbp += delta;
+		cbc -= delta;
+//print("now at %lld\n", cpos());
+		return;
+	}
+
+	cflush();
+	seek(cout, p, 0);
+	coutpos = p;
+}
+
+void
+cwrite(void *buf, int n)
+{
+	cflush();
+	if(write(cout, buf, n) != n) {
+		diag("write error: %r");
+		errorexit();
+	}
+	coutpos += n;
+}
+
+void
+cseekend(void)
+{
+	seek(cout, 0, 2);
+}

src/cmd/ld/lib.h

@@ -102,7 +102,6 @@ struct Section
 extern	char	symname[];
 extern	char	*libdir[];
 extern	int	nlibdir;
-extern	int	cout;
 
 EXTERN	char*	INITENTRY;
 EXTERN	char*	thestring;
@@ -169,7 +168,6 @@ void	mark(Sym *s);
 void	mkfwd(void);
 char*	expandpkg(char*, char*);
 void	deadcode(void);
-void	ewrite(int, void*, int);
 Reloc*	addrel(Sym*);
 void	codeblk(int32, int32);
 void	datblk(int32, int32);
@@ -279,3 +277,27 @@ int	headtype(char*);
 
 int	Yconv(Fmt*);
 #pragma	varargck	type	"Y"	Sym*
+
+// buffered output
+
+EXTERN	Biobuf	bso;
+
+EXTERN struct
+{
+	char	cbuf[MAXIO];	/* output buffer */
+} buf;
+
+EXTERN	int	cbc;
+EXTERN	char*	cbp;
+EXTERN	char*	cbpmax;
+
+#define	cput(c)\
+	{ *cbp++ = c;\
+	if(--cbc <= 0)\
+		cflush(); }
+
+void	cflush(void);
+vlong	cpos(void);
+void	cseek(vlong);
+void	cseekend(void);
+void	cwrite(void*, int);

src/cmd/ld/macho.c

@@ -506,12 +506,12 @@ domacholink(void)
 
 	if(size > 0) {
 		linkoff = rnd(HEADR+segtext.len, INITRND) + rnd(segdata.filelen, INITRND);
-		seek(cout, linkoff, 0);
+		cseek(linkoff);
 
-		ewrite(cout, s1->p, s1->size);
-		ewrite(cout, s2->p, s2->size);
-		ewrite(cout, s3->p, s3->size);
-		ewrite(cout, s4->p, s4->size);
+		cwrite(s1->p, s1->size);
+		cwrite(s2->p, s2->size);
+		cwrite(s3->p, s3->size);
+		cwrite(s4->p, s4->size);
 	}
 
 	return rnd(size, INITRND);

src/cmd/ld/pe.c

@@ -135,20 +135,20 @@ peinit(void)
 static void
 pewrite(void)
 {
-	seek(cout, 0, 0);
-	ewrite(cout, dosstub, sizeof dosstub);
+	cseek(0);
+	cwrite(dosstub, sizeof dosstub);
 	strnput("PE", 4);
 	cflush();
 	// TODO: This code should not assume that the
 	// memory representation is little-endian or
 	// that the structs are packed identically to
 	// their file representation.
-	ewrite(cout, &fh, sizeof fh);
+	cwrite(&fh, sizeof fh);
 	if(pe64)
-		ewrite(cout, &oh64, sizeof oh64);
+		cwrite(&oh64, sizeof oh64);
 	else
-		ewrite(cout, &oh, sizeof oh);
-	ewrite(cout, sh, nsect * sizeof sh[0]);
+		cwrite(&oh, sizeof oh);
+	cwrite(sh, nsect * sizeof sh[0]);
 }
 
 static void
@@ -227,7 +227,7 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
 	n = 0;
 	for(d = dr; d != nil; d = d->next)
 		n++;
-	seek(cout, fileoff + sizeof(IMAGE_IMPORT_DESCRIPTOR) * (n + 1), 0);
+	cseek(fileoff + sizeof(IMAGE_IMPORT_DESCRIPTOR) * (n + 1));
 
 	// write dll names
 	for(d = dr; d != nil; d = d->next) {
@@ -264,7 +264,7 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
 
 	// write FirstThunks (allocated in .data section)
 	ftbase = dynamic->value - datsect->VirtualAddress - PEBASE;
-	seek(cout, datsect->PointerToRawData + ftbase, 0);
+	cseek(datsect->PointerToRawData + ftbase);
 	for(d = dr; d != nil; d = d->next) {
 		for(m = d->ms; m != nil; m = m->next)
 			put(m->off);
@@ -273,7 +273,7 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
 	cflush();
 	
 	// finally write import descriptor table
-	seek(cout, fileoff, 0);
+	cseek(fileoff);
 	for(d = dr; d != nil; d = d->next) {
 		lputl(isect->VirtualAddress + oftbase + d->thunkoff);
 		lputl(0);
@@ -294,7 +294,7 @@ addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect)
 	dd[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = dynamic->value - PEBASE;
 	dd[IMAGE_DIRECTORY_ENTRY_IAT].Size = dynamic->size;
 
-	seek(cout, 0, 2);
+	cseekend();
 }
 
 static int
@@ -348,7 +348,7 @@ addexports(vlong fileoff)
 	dd[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress = va;
 	dd[IMAGE_DIRECTORY_ENTRY_EXPORT].Size = sect->VirtualSize;
 
-	seek(cout, fileoff, 0);
+	cseek(fileoff);
 	va_name = va + sizeof e + nexport*4;
 	va_addr = va + sizeof e;
 	va_na = va + sizeof e + nexport*8;
@@ -385,7 +385,7 @@ addexports(vlong fileoff)
 	strnput("", sect->SizeOfRawData - size);
 	cflush();
 
-	seek(cout, 0, 2);
+	cseekend();
 }
 
 void
@@ -491,7 +491,7 @@ addpersrc(void)
 		p[2] = val>>16;
 		p[3] = val>>24;
 	}
-	ewrite(cout, rsrcsym->p, rsrcsym->size);
+	cwrite(rsrcsym->p, rsrcsym->size);
 	strnput("", h->SizeOfRawData - rsrcsym->size);
 	cflush();