hush: tighten up "for" variable name check.

Add TODOs.
 Disable redir4.right part where we differ from bash.
 It is not a bug per standards.
 Add a few tests, one is in hush-bugs section:
 and_or_and_backgrounding.right. It will likely bite users
 in real world usage.

shell/hush.c

@@ -344,8 +344,7 @@ typedef enum redir_type {
 
 	REDIRFD_CLOSE      = -3,
 	REDIRFD_SYNTAX_ERR = -2,
-	REDIRFD_TO_FILE    = -1,
-	/* otherwise, rd_fd is redirected to rd_dup */
+	REDIRFD_TO_FILE    = -1, /* otherwise, rd_fd if redirected to rd_dup */
 
 	HEREDOC_SKIPTABS = 1,
 	HEREDOC_QUOTED   = 2,
@@ -3999,6 +3998,7 @@ static int done_word(o_string *word, struct parse_context *ctx)
 			ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED;
 		}
 		debug_printf_parse("word stored in rd_filename: '%s'\n", word->data);
+		ctx->pending_redirect = NULL;
 	} else {
 		/* If this word wasn't an assignment, next ones definitely
 		 * can't be assignments. Even if they look like ones. */
@@ -4076,19 +4076,19 @@ static int done_word(o_string *word, struct parse_context *ctx)
 		debug_print_strings("word appended to argv", command->argv);
 	}
 
-	o_reset(word);
-	ctx->pending_redirect = NULL;
-
 #if ENABLE_HUSH_LOOPS
-	/* Force FOR to have just one word (variable name) */
-	/* NB: basically, this makes hush see "for v in ..." syntax as if
-	 * as it is "for v; in ...". FOR and IN become two pipe structs
-	 * in parse tree. */
 	if (ctx->ctx_res_w == RES_FOR) {
-		if (!is_well_formed_var_name(command->argv[0], '\0')) {
-			syntax_error("malformed variable name in for");
+		if (word->o_quoted
+		 || !is_well_formed_var_name(command->argv[0], '\0')
+		) {
+			/* bash says "not a valid identifier" */
+			syntax_error("not a valid identifier in for");
 			return 1;
 		}
+		/* Force FOR to have just one word (variable name) */
+		/* NB: basically, this makes hush see "for v in ..."
+		 * syntax as if it is "for v; in ...". FOR and IN become
+		 * two pipe structs in parse tree. */
 		done_pipe(ctx, PIPE_SEQ);
 	}
 #endif
@@ -4098,6 +4098,9 @@ static int done_word(o_string *word, struct parse_context *ctx)
 		done_pipe(ctx, PIPE_SEQ);
 	}
 #endif
+
+	o_reset(word);
+
 	debug_printf_parse("done_word return 0\n");
 	return 0;
 }
@@ -6197,6 +6200,8 @@ static int builtin_read(char **argv)
 
 	if (argv[1]) {
 		name = argv[1];
+		/* bash (3.2.33(1)) bug: "read 0abcd" will execute,
+		 * and _after_ that_ it will complain */
 		if (!is_well_formed_var_name(name, '\0')) {
 			/* Mimic bash message */
 			bb_error_msg("read: '%s': not a valid identifier", name);
@@ -6204,6 +6209,8 @@ static int builtin_read(char **argv)
 		}
 	}
 
+//TODO: bash unbackslashes input, splits words and puts them in argv[i]
+
 	string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name), NULL);
 	return set_local_var(string, 0, 0);
 }

shell/hush_test/hush-bugs/and_or_and_backgrounding.right

@@ -0,0 +1,4 @@
+First
+Second
+Third
+Done

shell/hush_test/hush-bugs/and_or_and_backgrounding.tests

@@ -0,0 +1,31 @@
+# UNFIXED BUG: hush thinks that ; && || & have the same precedence.
+# According to this doc, && || have higher precedence than ; &.
+# See example below.
+# Precedence of ; is not a problem in practice. Precedence of & is.
+#
+#http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+#
+#2.9.3 Lists
+#
+#An AND-OR list is a sequence of one or more pipelines separated by
+#the operators "&&" and "||" .
+#
+#A list is a sequence of one or more AND-OR lists separated by the operators
+#';' and '&' and optionally terminated by ';', '&', or <newline>.
+#
+#The operators "&&" and "||" shall have equal precedence and shall be
+#evaluated with left associativity. For example, both of the following
+#commands write solely bar to standard output:
+#
+#    false && echo foo || echo bar
+#    true || echo foo && echo bar
+#
+#A ';' or <newline> terminator shall cause the preceding AND-OR list
+#to be executed sequentially; an '&' shall cause asynchronous execution
+#of the preceding AND-OR list.
+
+echo First && sleep 0.2 && echo Third &
+sleep 0.1
+echo Second
+wait
+echo Done

shell/hush_test/hush-misc/for_with_bslashes.right

@@ -0,0 +1,8 @@
+a
+b\c
+b\\c
+b"c
+b'c
+b$c
+b`true`c
+Zero:0

shell/hush_test/hush-misc/for_with_bslashes.tests

@@ -0,0 +1,10 @@
+# UNFIXED BUG.
+# commented-out words contain ^C character.
+# It's a SPECIAL_VAR_SYMBOL, for now hush does not escape it.
+# When it is fixed, update this test.
+
+for a in 'a' 'b\c' 'b\\c' 'b"c' "b'c" 'b$c' 'b`true`c' ### 'b#c'
+do
+    echo $a
+done
+echo Zero:$?

shell/hush_test/hush-misc/redir1.tests

@@ -27,7 +27,7 @@ var=ok
 { var=bad >shell_test_$$; } &
 # cant use usleep as it isnt standard in $PATH --
 # we fail when testing busybox compiled solely as "hush"
-sleep 1
+wait
 echo "Test 4:  var:$var"
 test -f shell_test_$$ && echo "File created:ok"
 

shell/hush_test/hush-misc/redir4.right

@@ -10,16 +10,9 @@ Here3
 Ok3
 Here4
 Ok4
-How with variable refs
+Now with variable refs
 shell_test_1
 \shell_test_1
 \shell_test_1
 \shell_test_1
-Here1
-Ok1
-Here2
-Ok2
-Here3
-Ok3
-Here4
-Ok4
+Done

shell/hush_test/hush-misc/redir4.tests

@@ -38,7 +38,7 @@ Here4
 echo Ok4
 
 
-echo How with variable refs
+echo Now with variable refs
 i=1
 
 
@@ -58,6 +58,11 @@ rm *shell_test*
 echo *shell_test*
 rm *shell_test*
 
+echo Done;exit
+# UNFIXED BUG. bash apparently will expand $i even in terminating delimiter.
+# http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+# does not mandate this behavior.
+# This is not likely to be used much in real-world.
 
 cat <<\shell_test_$i
 Here1

shell/hush_test/hush-vars/param_subshell.tests

@@ -7,9 +7,9 @@ echo 1=$1
 { echo 3=$3; } &
 # cant use usleep as it isnt standard in $PATH --
 # we fail when testing busybox compiled solely as "hush"
-sleep 1
+wait
 ( echo 4=$4 )
 ( echo 5=$5 ) &
-sleep 1
+wait
 true | echo 6=$6 | cat
 true | { echo 7=$7; } | cat