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6e42b89b8

Denys Vlasenko

2011-08-01

FAILED Duration: 230s

Subject

hush: fix remaining known two bugs with IFS expansion. Closes 4027.

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

shell/hush.c +55 -27 shell/hush_test/hush-parsing/starquoted2.right +3 -0 shell/hush_test/hush-parsing/starquoted2.tests +3 -3

shell/hush.c+55 -27

@@ -3265,14 +3265,6 @@ static int done_word(o_string word, struct parse_context ctx)
	) {
	p += 3;
	}
-	if (p == word->data \|\| p[0] != '\0') {
-	/* saw no "$@", or not only "$@" but some
-	* real text is there too */
-	/* insert "empty variable" reference, this makes
-	* e.g. "", $empty"" etc to not disappear */
-	o_addchr(word, SPECIAL_VAR_SYMBOL);
-	o_addchr(word, SPECIAL_VAR_SYMBOL);
-	}
	}
	command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
	debug_print_strings("word appended to argv", command->argv);
@@ -4516,20 +4508,30 @@ static struct pipe parse_stream(char *pstring,
	break;
	case '\'':
	dest.has_quoted_part = 1;
-	while (1) {
-	ch = i_getch(input);
-	if (ch == EOF) {
-	syntax_error_unterm_ch('\'');
-	goto parse_error;
+	if (next == '\'' && !ctx.pending_redirect) {
+	insert_empty_quoted_str_marker:
+	nommu_addchr(&ctx.as_string, next);
+	i_getch(input); /* eat second ' */
+	o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+	o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+	} else {
+	while (1) {
+	ch = i_getch(input);
+	if (ch == EOF) {
+	syntax_error_unterm_ch('\'');
+	goto parse_error;
+	}
+	nommu_addchr(&ctx.as_string, ch);
+	if (ch == '\'')
+	break;
+	o_addqchr(&dest, ch);
	}
-	nommu_addchr(&ctx.as_string, ch);
-	if (ch == '\'')
-	break;
-	o_addqchr(&dest, ch);
	}
	break;
	case '"':
	dest.has_quoted_part = 1;
+	if (next == '"' && !ctx.pending_redirect)
+	goto insert_empty_quoted_str_marker;
	if (dest.o_assignment == NOT_ASSIGNMENT)
	dest.o_expflags \|= EXP_FLAG_ESC_GLOB_CHARS;
	if (!encode_string(&ctx.as_string, &dest, input, '"', /process_bkslash:/ 1))
@@ -4751,9 +4753,14 @@ static void o_addblock_duplicate_backslash(o_string o, const char str, int len

	/* Store given string, finalizing the word and starting new one whenever
	* we encounter IFS char(s). This is used for expanding variable values.
-	* End-of-string does NOT finalize word: think about 'echo -$VAR-' */
-	static int expand_on_ifs(o_string output, int n, const char str)
+	* End-of-string does NOT finalize word: think about 'echo -$VAR-'.
+	* Return in *ended_with_ifs:
+	* 1 - ended with IFS char, else 0 (this includes case of empty str).
+	*/
+	static int expand_on_ifs(int ended_with_ifs, o_string output, int n, const char *str)
	{
+	int last_is_ifs = 0;
+
	while (1) {
	int word_len;

@@ -4774,27 +4781,36 @@ static int expand_on_ifs(o_string output, int n, const char str)
	/o_addblock(output, str, word_len); - WRONG: "v='\'; echo Z$v" prints "Z" instead of "Z\" */
	/o_addqblock(output, str, word_len); - WRONG: "v=''; echo Z$v" prints "Z" instead of Z files */
	}
+	last_is_ifs = 0;
	str += word_len;
	if (!str) / EOL - do not finalize word */
	break;
-	goto finalize; /* optimization (can just fall thru) */
	}
-	/* Case "v=' a'; echo ''$v": we do need to finalize empty word */
+
+	/* We know str here points to at least one IFS char */
+	last_is_ifs = 1;
+	str += strspn(str, G.ifs); /* skip IFS chars */
+	if (!str) / EOL - do not finalize word */
+	break;
+
+	/* Start new word... but not always! */
+	/* Case "v=' a'; echo ''$v": we do need to finalize empty word: */
	if (output->has_quoted_part
	/* Case "v=' a'; echo $v":
	* here nothing precedes the space in $v expansion,
	* therefore we should not finish the word
-	* (IOW: if there is word to finalize, only then do it)
+	* (IOW: if there is word to finalize, only then do it):
	*/
-	\|\| (output->length && output->data[output->length - 1])
+	\|\| (n > 0 && output->data[output->length - 1])
	) {
-	finalize:
	o_addchr(output, '\0');
	debug_print_list("expand_on_ifs", output, n);
	n = o_save_ptr(output, n);
	}
-	str += strspn(str, G.ifs); /* skip IFS chars */
	}
+
+	if (ended_with_ifs)
+	*ended_with_ifs = last_is_ifs;
	debug_print_list("expand_on_ifs[1]", output, n);
	return n;
	}
@@ -5209,6 +5225,7 @@ static NOINLINE int expand_vars_to_list(o_string output, int n, char arg)
	* expansion of right-hand side of assignment == 1-element expand.
	*/
	char cant_be_null = 0; /* only bit 0x80 matters */
+	int ended_in_ifs = 0; /* did last unquoted expansion end with IFS chars? */
	char *p;

	debug_printf_expand("expand_vars_to_list: arg:'%s' singleword:%x\n", arg,
@@ -5227,6 +5244,13 @@ static NOINLINE int expand_vars_to_list(o_string output, int n, char arg)
	#if ENABLE_SH_MATH_SUPPORT
	char arith_buf[sizeof(arith_t)*3 + 2];
	#endif
+
+	if (ended_in_ifs) {
+	o_addchr(output, '\0');
+	n = o_save_ptr(output, n);
+	ended_in_ifs = 0;
+	}
+
	o_addblock(output, arg, p - arg);
	debug_print_list("expand_vars_to_list[1]", output, n);
	arg = ++p;
@@ -5255,7 +5279,7 @@ static NOINLINE int expand_vars_to_list(o_string output, int n, char arg)
	cant_be_null \|= first_ch; /* do it for "$@" _now_, when we know it's not empty */
	if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
	while (G.global_argv[i]) {
-	n = expand_on_ifs(output, n, G.global_argv[i]);
+	n = expand_on_ifs(NULL, output, n, G.global_argv[i]);
	debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
	if (G.global_argv[i++][0] && G.global_argv[i]) {
	/* this argv[] is not empty and not last:
@@ -5332,7 +5356,7 @@ static NOINLINE int expand_vars_to_list(o_string output, int n, char arg)
	debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val,
	!!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
	if (val && val[0]) {
-	n = expand_on_ifs(output, n, val);
+	n = expand_on_ifs(&ended_in_ifs, output, n, val);
	val = NULL;
	}
	} else { /* quoted $VAR, val will be appended below */
@@ -5361,6 +5385,10 @@ static NOINLINE int expand_vars_to_list(o_string output, int n, char arg)
	} /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */

	if (arg[0]) {
+	if (ended_in_ifs) {
+	o_addchr(output, '\0');
+	n = o_save_ptr(output, n);
+	}
	debug_print_list("expand_vars_to_list[a]", output, n);
	/* this part is literal, and it was already pre-quoted
	* if needed (much earlier), do not use o_addQstr here! */

shell/hush_test/hush-parsing/starquoted2.right+3 -0

@@ -1,4 +1,7 @@
	Should be printed
+	Would not be printed by bash
+	Would not be printed by bash
+	Would not be printed by bash
	Should be printed
	Empty:
	Empty:

shell/hush_test/hush-parsing/starquoted2.tests+3 -3

@@ -8,9 +8,9 @@ for a in "$@"; do echo Should not be printed; done
	# Yes, believe it or not, bash is mesmerized by "$@" and stops
	# treating "" as "this word cannot be expanded to nothing,
	# but must be at least null string". Now it can be expanded to nothing.
-	for a in "$@"""; do echo Should not be printed; done
-	for a in """$@"; do echo Should not be printed; done
-	for a in """$@"''"$@"''; do echo Should not be printed; done
+	for a in "$@"""; do echo Would not be printed by bash; done
+	for a in """$@"; do echo Would not be printed by bash; done
+	for a in """$@"''"$@"''; do echo Would not be printed by bash; done
	for a in ""; do echo Should be printed; done

	# Bug 207: "$@" expands to nothing, and we erroneously glob "%s\n" twice: