sh: Expand aliases after assignments and redirections.

svn path=/head/; revision=222165

bin/sh/eval.c

@@ -714,15 +714,9 @@ evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
 	oexitstatus = exitstatus;
 	exitstatus = 0;
 	for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
-		char *p = argp->narg.text;
-		if (varflag && is_name(*p)) {
-			do {
-				p++;
-			} while (is_in_name(*p));
-			if (*p == '=') {
-				expandarg(argp, &varlist, EXP_VARTILDE);
-				continue;
-			}
+		if (varflag && isassignment(argp->narg.text)) {
+			expandarg(argp, &varlist, EXP_VARTILDE);
+			continue;
 		}
 		expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
 		varflag = 0;

bin/sh/parser.c

@@ -619,6 +619,7 @@ simplecmd(union node **rpp, union node *redir)
 	union node **orig_rpp = rpp;
 	union node *n = NULL;
 	int special;
+	int savecheckkwd;
 
 	/* If we don't have any redirections already, then we must reset */
 	/* rpp to be the address of the local redir variable.  */
@@ -634,7 +635,10 @@ simplecmd(union node **rpp, union node *redir)
 	 */
 	orig_rpp = rpp;
 
+	savecheckkwd = CHKALIAS;
+
 	for (;;) {
+		checkkwd = savecheckkwd;
 		if (readtoken() == TWORD) {
 			n = (union node *)stalloc(sizeof (struct narg));
 			n->type = NARG;
@@ -642,6 +646,8 @@ simplecmd(union node **rpp, union node *redir)
 			n->narg.backquote = backquotelist;
 			*app = n;
 			app = &n->narg.next;
+			if (savecheckkwd != 0 && !isassignment(wordtext))
+				savecheckkwd = 0;
 		} else if (lasttoken == TREDIR) {
 			*rpp = n = redirnode;
 			rpp = &n->nfile.next;
@@ -1859,6 +1865,22 @@ goodname(const char *name)
 }
 
 
+int
+isassignment(const char *p)
+{
+	if (!is_name(*p))
+		return 0;
+	p++;
+	for (;;) {
+		if (*p == '=')
+			return 1;
+		else if (!is_in_name(*p))
+			return 0;
+		p++;
+	}
+}
+
+
 /*
  * Called when an unexpected token is read during the parse.  The argument
  * is the token that is expected, or -1 if more than one type of token can

bin/sh/parser.h

@@ -80,4 +80,5 @@ extern const char *const parsekwd[];
 union node *parsecmd(int);
 void fixredir(union node *, const char *, int);
 int goodname(const char *);
+int isassignment(const char *);
 char *getprompt(void *);

bin/sh/sh.1

@@ -32,7 +32,7 @@
 .\"	from: @(#)sh.1	8.6 (Berkeley) 5/4/95
 .\" $FreeBSD$
 .\"
-.Dd May 20, 2011
+.Dd May 21, 2011
 .Dt SH 1
 .Os
 .Sh NAME
@@ -506,8 +506,8 @@ The following are keywords:
 An alias is a name and corresponding value set using the
 .Ic alias
 built-in command.
-Whenever a keyword may occur (see above),
-and after checking for keywords, the shell
+Wherever the command word of a simple command may occur,
+and after checking for keywords if a keyword may occur, the shell
 checks the word to see if it matches an alias.
 If it does, it replaces it in the input stream with its value.
 For example, if there is an alias called

tools/regression/bin/sh/parser/alias4.0

@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+alias alias0=exit
+eval 'x=1 alias0 0'
+exit 1

tools/regression/bin/sh/parser/alias5.0

@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+alias alias0=exit
+eval '</dev/null alias0 0'
+exit 1