hush: fix remaining known two bugs with IFS expansion. Closes 4027.
function old new delta
expand_vars_to_list 1054 1140 +86
parse_stream 2425 2479 +54
expand_on_ifs 258 310 +52
builtin_umask 133 132 -1
done_word 820 779 -41
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/2 up/down: 192/-42) Total: 150 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/hush.c b/shell/hush.c
index 503cb77..6b30277 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -3265,14 +3265,6 @@
) {
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. "", $empty"" etc to not disappear */
- o_addchr(word, SPECIAL_VAR_SYMBOL);
- o_addchr(word, SPECIAL_VAR_SYMBOL);
- }
}
command->argv = add_string_to_strings(command->argv, xstrdup(word->data));
debug_print_strings("word appended to argv", command->argv);
@@ -4516,20 +4508,30 @@
break;
case '\'':
dest.has_quoted_part = 1;
- while (1) {
- ch = i_getch(input);
- if (ch == EOF) {
- syntax_error_unterm_ch('\'');
- goto parse_error;
+ if (next == '\'' && !ctx.pending_redirect) {
+ insert_empty_quoted_str_marker:
+ nommu_addchr(&ctx.as_string, next);
+ i_getch(input); /* eat second ' */
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ } else {
+ while (1) {
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ goto parse_error;
+ }
+ nommu_addchr(&ctx.as_string, ch);
+ if (ch == '\'')
+ break;
+ o_addqchr(&dest, ch);
}
- nommu_addchr(&ctx.as_string, ch);
- if (ch == '\'')
- break;
- o_addqchr(&dest, ch);
}
break;
case '"':
dest.has_quoted_part = 1;
+ if (next == '"' && !ctx.pending_redirect)
+ goto insert_empty_quoted_str_marker;
if (dest.o_assignment == NOT_ASSIGNMENT)
dest.o_expflags |= EXP_FLAG_ESC_GLOB_CHARS;
if (!encode_string(&ctx.as_string, &dest, input, '"', /*process_bkslash:*/ 1))
@@ -4751,9 +4753,14 @@
/* Store given string, finalizing the word and starting new one whenever
* we encounter IFS char(s). This is used for expanding variable values.
- * End-of-string does NOT finalize word: think about 'echo -$VAR-' */
-static int expand_on_ifs(o_string *output, int n, const char *str)
+ * End-of-string does NOT finalize word: think about 'echo -$VAR-'.
+ * Return in *ended_with_ifs:
+ * 1 - ended with IFS char, else 0 (this includes case of empty str).
+ */
+static int expand_on_ifs(int *ended_with_ifs, o_string *output, int n, const char *str)
{
+ int last_is_ifs = 0;
+
while (1) {
int word_len;
@@ -4774,27 +4781,36 @@
/*o_addblock(output, str, word_len); - WRONG: "v='\*'; echo Z$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 $v expansion,
* therefore we should not finish the word
- * (IOW: if there *is* word to finalize, only then do it)
+ * (IOW: if there *is* word to finalize, only then do it):
*/
- || (output->length && output->data[output->length - 1])
+ || (n > 0 && output->data[output->length - 1])
) {
- finalize:
o_addchr(output, '\0');
debug_print_list("expand_on_ifs", output, n);
n = o_save_ptr(output, n);
}
- str += strspn(str, G.ifs); /* skip IFS chars */
}
+
+ if (ended_with_ifs)
+ *ended_with_ifs = last_is_ifs;
debug_print_list("expand_on_ifs[1]", output, n);
return n;
}
@@ -5209,6 +5225,7 @@
* expansion of right-hand side of assignment == 1-element expand.
*/
char cant_be_null = 0; /* only bit 0x80 matters */
+ int ended_in_ifs = 0; /* did last unquoted expansion end with IFS chars? */
char *p;
debug_printf_expand("expand_vars_to_list: arg:'%s' singleword:%x\n", arg,
@@ -5227,6 +5244,13 @@
#if ENABLE_SH_MATH_SUPPORT
char arith_buf[sizeof(arith_t)*3 + 2];
#endif
+
+ if (ended_in_ifs) {
+ o_addchr(output, '\0');
+ n = o_save_ptr(output, n);
+ ended_in_ifs = 0;
+ }
+
o_addblock(output, arg, p - arg);
debug_print_list("expand_vars_to_list[1]", output, n);
arg = ++p;
@@ -5255,7 +5279,7 @@
cant_be_null |= first_ch; /* do it for "$@" _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 @@
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 @@
} /* 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! */