5a, 5c, 6a, 6c, 8a, 8c: fix Windows file paths

Verified with objdump -W.

R=alex.brainman, rsc
CC=golang-dev
https://golang.org/cl/4974061

include/libc.h

@@ -307,6 +307,8 @@ extern int nanosleep(const struct timespec *rqtp, struct timespec *rmtp);
 extern int fork(void);
 extern int pread(int fd, void *buf, int n, int off);
 extern int pwrite(int fd, void *buf, int n, int off);
+#undef  getwd
+#define getwd(s, ns) getcwd(s, ns)
 #undef  lseek
 #define lseek(fd, n, base) _lseeki64(fd, n, base)
 #define mkdir(path, perm) mkdir(path)

src/cmd/5a/lex.c

@@ -44,7 +44,11 @@ enum
 int
 systemtype(int sys)
 {
+#ifdef _WIN32
+	return sys&Windows;
+#else
 	return sys&Plan9;
+#endif
 }
 
 void
@@ -643,17 +647,13 @@ outhist(void)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;

src/cmd/5c/swt.c

@@ -460,17 +460,13 @@ outhist(Biobuf *b)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;

src/cmd/6a/lex.c

@@ -44,7 +44,11 @@ enum
 int
 systemtype(int sys)
 {
+#ifdef _WIN32
+	return sys&Windows;
+#else
 	return sys&Plan9;
+#endif
 }
 
 int
@@ -1251,17 +1255,13 @@ outhist(void)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;

src/cmd/6c/swt.c

@@ -331,17 +331,13 @@ outhist(Biobuf *b)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;

src/cmd/8a/lex.c

@@ -44,7 +44,11 @@ enum
 int
 systemtype(int sys)
 {
+#ifdef _WIN32
+	return sys&Windows;
+#else
 	return sys&Plan9;
+#endif
 }
 
 int
@@ -912,17 +916,13 @@ outhist(void)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;

src/cmd/8c/swt.c

@@ -330,17 +330,13 @@ outhist(Biobuf *b)
 	for(h = hist; h != H; h = h->link) {
 		p = h->name;
 		op = 0;
-		/* on windows skip drive specifier in pathname */
 		if(systemtype(Windows) && p && p[1] == ':'){
-			p += 2;
-			c = *p;
-		}
-		if(p && p[0] != c && h->offset == 0 && pathname){
-			/* on windows skip drive specifier in pathname */
+			c = p[2];
+		} else if(p && p[0] != c && h->offset == 0 && pathname){
 			if(systemtype(Windows) && pathname[1] == ':') {
 				op = p;
-				p = pathname+2;
-				c = *p;
+				p = pathname;
+				c = p[2];
 			} else if(pathname[0] == c){
 				op = p;
 				p = pathname;