WIP: add nash syntax support for mk

src/cmd/mk/mk.h

@@ -164,7 +164,7 @@ extern	char	*explain;
 extern	Shell	*shellt;
 extern	Word	*shellcmd;
 
-extern	Shell	shshell, rcshell;
+extern	Shell	shshell, rcshell, nashshell;
 
 #define	SYNERR(l)	(fprint(2, "mk: %s:%d: syntax error; ", infile, ((l)>=0)?(l):mkinline))
 #define	RERR(r)		(fprint(2, "mk: %s:%d: rule error; ", (r)->file, (r)->line))

src/cmd/mk/mkfile

@@ -17,6 +17,7 @@ OFILES=\
 	parse.$O\
 	recipe.$O\
 	rc.$O\
+	nash.$O\
 	rule.$O\
 	run.$O\
 	sh.$O\

src/cmd/mk/mkfile.test

@@ -10,3 +10,22 @@ use-sh:V:
 		echo $i
 	done
 
+MKSHELL=$HOME/nashroot/bin/nash
+use-nash:V:
+	for i in ("a" "b" "c") {
+		echo $i
+	}
+
+# complex nash syntax
+use-nash2:V:
+	var stdout, stderr, status <= ls /
+	if $status != "0" {
+		echo "error: " $stderr
+		exit(1)
+	}
+	var paths <= split($stdout, "\n")
+	for p in $paths {
+		echo $p
+	}
+
+

src/cmd/mk/nash.c

@@ -0,0 +1,161 @@
+#include	"mk.h"
+
+/*
+ *	This file contains functions that depend on nash's syntax. 
+ */
+
+/*
+ *	skip a token in quotes.
+ */
+static char *
+nashsquote(char *cp, int c)
+{
+	Rune r;
+	int n;
+
+	while(*cp){
+		n = chartorune(&r, cp);
+		if(r == c)
+			return cp;
+		if(r == '\\')
+			n += chartorune(&r, cp+n);
+		cp += n;
+	}
+	SYNERR(-1);		/* should never occur */
+	fprint(2, "missing closing '\n");
+	return 0;
+}
+/*
+ *	search a string for unescaped characters in a pattern set
+ */
+static char *
+nashcharin(char *cp, char *pat)
+{
+	Rune r;
+	int n, vargen;
+
+	vargen = 0;
+	while(*cp){
+		n = chartorune(&r, cp);
+		switch(r){
+		case '\\':			/* skip escaped char */
+			cp += n;
+			n = chartorune(&r, cp);
+			break;
+		case '"':
+			cp = nashsquote(cp+1, r);	/* n must = 1 */
+			if(!cp)
+				return 0;
+			break;
+		case '$':
+			if(*(cp+1) == '{')
+				vargen = 1;
+			break;
+		case '}':
+			if(vargen)
+				vargen = 0;
+			else if(utfrune(pat, r))
+				return cp;
+			break;
+		default:
+			if(vargen == 0 && utfrune(pat, r))
+				return cp;
+			break;
+		}
+		cp += n;
+	}
+	if(vargen){
+		SYNERR(-1);
+		fprint(2, "missing closing } in pattern generator\n");
+	}
+	return 0;
+}
+
+/*
+ *	extract an escaped token.  Possible escape chars are single-quote,
+ *	double-quote,and backslash.  Nash only has double-quotes and
+ * 	backslack have to be inserted again into buffer.
+ */
+char*
+nashexpandquote(char *s, Rune r, Bufblock *b)
+{
+	if(r != '"') {
+		rinsert(b, r);
+		return s;
+	}
+
+	/* inside double-quote */
+	while(*s){
+		s += chartorune(&r, s);
+		if(r == '"') {
+			if(*s == '"') 
+				s++;
+			else
+				return s;
+		}
+		rinsert(b, r); /* consumes the string */
+	}
+
+	return 0;
+}
+
+/*
+ *	Input an escaped token.  Possible escape chars are single-quote,
+ *	double-quote and backslash.  Only the first is a valid escape for
+ *	rc; the others are just inserted into the receiving buffer.
+ */
+int
+nashescapetoken(Biobuf *bp, Bufblock *buf, int preserve, int esc)
+{
+	SYNERR(-1); 
+	return 0;
+}
+
+/*
+ *	check for quoted strings.
+ *	s points to char after opening quote, q.
+ */
+char *
+nashcopyq(char *s, Rune q, Bufblock *buf)
+{
+	Rune r;
+	if(q == '"') {
+		while(*s){
+			s += chartorune(&r, s);
+			rinsert(buf, r);
+			if(r == '"')
+				break;
+		}
+	}
+
+	return s;
+}
+
+static int
+nashmatchname(char *name)
+{
+	char *p;
+
+	if((p = strrchr(name, '/')) != nil)
+		name = p+1;
+	if(strlen(name)!=4)
+		return 0;
+
+	if(strcmp(name, "nash") == 0)
+		return 1;
+	return 0;
+}
+
+Shell nashshell = {
+	"nash",
+	"\"= \t",
+
+	/* 	nash doesn't have IFS but otherwise we
+		cannot access lists from mk */
+	' ', 
+	nashcharin,
+	nashexpandquote,
+	nashescapetoken,
+	nashcopyq,
+	nashmatchname
+};

src/cmd/mk/run.c

@@ -78,7 +78,8 @@ sched(void)
 		if(DEBUG(D_EXEC))
 			fprint(1, "recipe='%s'", j->r->recipe);/**/
 		Bflush(&bout);
-		if(j->r->attr&NOMINUSE)
+		if(j->r->attr&NOMINUSE || 
+			strcmp(j->r->shellt->name, "nash")==0)
 			flags = 0;
 		else
 			flags = "-e";

src/cmd/mk/shell.c

@@ -1,6 +1,7 @@
 #include "mk.h"
 
 static Shell *shells[] = {
+	&nashshell,
 	&rcshell,
 	&shshell
 };