Plan 9's rc.

not a clear win over byron's,
but at least it has the right syntax.

1 files changed, 108 insertions, 0 deletions

diff --git a/src/cmd/rc/pcmd.c b/src/cmd/rc/pcmd.c
new file mode 100644
index 00000000..0f84298a
--- /dev/null
+++ b/src/cmd/rc/pcmd.c
@@ -0,0 +1,108 @@
+#include "rc.h"
+#include "io.h"
+#include "fns.h"
+char nl='\n';		/* change to semicolon for bourne-proofing */
+#define	c0	t->child[0]
+#define	c1	t->child[1]
+#define	c2	t->child[2]
+void pdeglob(io *f, char *s)
+{
+	while(*s){
+		if(*s==GLOB) s++;
+		pchr(f, *s++);
+	}
+}
+void pcmd(io *f, tree *t)
+{
+	if(t==0) return;
+	switch(t->type){
+	default:	pfmt(f, "bad %d %p %p %p", t->type, c0, c1, c2); break;
+	case '$':	pfmt(f, "$%t", c0); break;
+	case '"':	pfmt(f, "$\"%t", c0); break;
+	case '&':	pfmt(f, "%t&", c0); break;
+	case '^':	pfmt(f, "%t^%t", c0, c1); break;
+	case '`':	pfmt(f, "`%t", c0); break;
+	case ANDAND:	pfmt(f, "%t && %t", c0, c1); break;
+	case BANG:	pfmt(f, "! %t", c0); break;
+	case BRACE:	pfmt(f, "{%t}", c0); break;
+	case COUNT:	pfmt(f, "$#%t", c0); break;
+	case FN:	pfmt(f, "fn %t %t", c0, c1); break;
+	case IF:	pfmt(f, "if%t%t", c0, c1); break;
+	case NOT:	pfmt(f, "if not %t", c0); break;
+	case OROR:	pfmt(f, "%t || %t", c0, c1); break;
+	case PCMD:
+	case PAREN:	pfmt(f, "(%t)", c0); break;
+	case SUB:	pfmt(f, "$%t(%t)", c0, c1); break;
+	case SIMPLE:	pfmt(f, "%t", c0); break;
+	case SUBSHELL:	pfmt(f, "@ %t", c0); break;
+	case SWITCH:	pfmt(f, "switch %t %t", c0, c1); break;
+	case TWIDDLE:	pfmt(f, "~ %t %t", c0, c1); break;
+	case WHILE:	pfmt(f, "while %t%t", c0, c1); break;
+	case ARGLIST:
+		if(c0==0)
+			pfmt(f, "%t", c1);
+		else if(c1==0)
+			pfmt(f, "%t", c0);
+		else
+			pfmt(f, "%t %t", c0, c1);
+		break;
+	case ';':
+		if(c0){
+			if(c1) pfmt(f, "%t%c%t", c0, nl, c1);
+			else pfmt(f, "%t", c0);
+		}
+		else pfmt(f, "%t", c1);
+		break;
+	case WORDS:
+		if(c0) pfmt(f, "%t ", c0);
+		pfmt(f, "%t", c1);
+		break;
+	case FOR:
+		pfmt(f, "for(%t", c0);
+		if(c1) pfmt(f, " in %t", c1);
+		pfmt(f, ")%t", c2);
+		break;
+	case WORD:
+		if(t->quoted) pfmt(f, "%Q", t->str);
+		else pdeglob(f, t->str);
+		break;
+	case DUP:
+		if(t->rtype==DUPFD)
+			pfmt(f, ">[%d=%d]", t->fd1, t->fd0); /* yes, fd1, then fd0; read lex.c */
+		else
+			pfmt(f, ">[%d=]", t->fd0);
+		pfmt(f, "%t", c1);
+		break;
+	case PIPEFD:
+	case REDIR:
+		switch(t->rtype){
+		case HERE:
+			pchr(f, '<');
+		case READ:
+			pchr(f, '<');
+			if(t->fd0!=0) pfmt(f, "[%d]", t->fd0);
+			break;
+		case APPEND:
+			pchr(f, '>');
+		case WRITE:
+			pchr(f, '>');
+			if(t->fd0!=1) pfmt(f, "[%d]", t->fd0);
+			break;
+		}
+		pfmt(f, "%t", c0);
+		if(c1) pfmt(f, " %t", c1);
+		break;
+	case '=':
+		pfmt(f, "%t=%t", c0, c1);
+		if(c2) pfmt(f, " %t", c2);
+		break;
+	case PIPE:
+		pfmt(f, "%t|", c0);
+		if(t->fd1==0){
+			if(t->fd0!=1) pfmt(f, "[%d]", t->fd0);
+		}
+		else pfmt(f, "[%d=%d]", t->fd0, t->fd1);
+		pfmt(f, "%t", c1);
+		break;
+	}
+}