hush: support ${var:EXPR:EXPR}!
function old new delta
handle_dollar 574 681 +107
expand_and_evaluate_arith - 77 +77
expand_vars_to_list 2302 2374 +72
add_till_closing_bracket 359 368 +9
builtin_exit 48 47 -1
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/1 up/down: 265/-1) Total: 264 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/hush.c b/shell/hush.c
index 0f0151a..41d5fca 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -171,6 +171,7 @@
#define debug_printf_env(...) do {} while (0)
#define debug_printf_jobs(...) do {} while (0)
#define debug_printf_expand(...) do {} while (0)
+#define debug_printf_varexp(...) do {} while (0)
#define debug_printf_glob(...) do {} while (0)
#define debug_printf_list(...) do {} while (0)
#define debug_printf_subst(...) do {} while (0)
@@ -743,6 +744,10 @@
# define DEBUG_EXPAND 0
#endif
+#ifndef debug_printf_varexp
+# define debug_printf_varexp(...) (indent(), fprintf(stderr, __VA_ARGS__))
+#endif
+
#ifndef debug_printf_glob
# define debug_printf_glob(...) (indent(), fprintf(stderr, __VA_ARGS__))
# define DEBUG_GLOB 1
@@ -1817,11 +1822,11 @@
o->data[o->length] = '\0';
}
-#if !BB_MMU
static void o_addstr(o_string *o, const char *str)
{
o_addblock(o, str, strlen(str));
}
+#if !BB_MMU
static void nommu_addchr(o_string *o, int ch)
{
if (o)
@@ -2597,12 +2602,19 @@
} else {
/* maybe handle parameter expansion */
exp_saveptr = var + strcspn(var, "%#:-=+?");
- exp_save = *exp_saveptr;
- if (exp_save) {
- exp_word = exp_saveptr;
- if (exp_save == ':')
- exp_word++;
- exp_op = *exp_word++;
+ exp_op = exp_save = *exp_saveptr;
+ if (exp_op) {
+ exp_word = exp_saveptr + 1;
+ if (exp_op == ':') {
+ exp_op = *exp_word++;
+ if (ENABLE_HUSH_BASH_COMPAT
+ && (exp_op == '\0' || !strchr("%#:-=+?"+3, exp_op))
+ ) {
+ /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */
+ exp_op = ':';
+ exp_word--;
+ }
+ }
*exp_saveptr = '\0';
}
}
@@ -2656,39 +2668,42 @@
*loc = '\0';
}
}
- } else if (!strchr("%#:-=+?"+3, exp_op)) {
+ } else if (exp_op == ':') {
#if ENABLE_HUSH_BASH_COMPAT
- /* exp_op is ':' and next char isn't a subst operator.
- * Assuming it's ${var:[N][:M]} bashism.
- * TODO: N, M can be expressions similar to $((EXPR)): 2+2, 2+var etc
+ /* It's ${var:N[:M]} bashism.
+ * Note that in encoded form it has TWO parts:
+ * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL>
*/
- char *end;
- unsigned len = INT_MAX;
- unsigned beg = 0;
- end = --exp_word;
- if (*exp_word != ':') /* not ${var::...} */
- beg = bb_strtou(exp_word, &end, 0);
- //bb_error_msg("beg:'%s'=%u end:'%s'", exp_word, beg, end);
- if (*end == ':') {
- if (end[1] != '\0') /* not ${var:NUM:} */
- len = bb_strtou(end + 1, &end, 0);
- else {
- len = 0;
- end++;
- }
- //bb_error_msg("len:%u end:'%s'", len, end);
- }
- if (*end == '\0') {
- //bb_error_msg("from val:'%s'", val);
+ arith_t beg, len;
+ int errcode = 0;
+
+ beg = expand_and_evaluate_arith(exp_word, &errcode);
+ debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg);
+ *p++ = SPECIAL_VAR_SYMBOL;
+ exp_word = p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ len = expand_and_evaluate_arith(exp_word, &errcode);
+ debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len);
+
+ if (errcode >= 0 && len >= 0) { /* bash compat: len < 0 is illegal */
+ if (beg < 0) /* bash compat */
+ beg = 0;
+ debug_printf_varexp("from val:'%s'\n", val);
if (len == 0 || !val || beg >= strlen(val))
val = "";
- else
+ else {
+ /* Paranoia. What if user entered 9999999999999
+ * which fits in arith_t but not int? */
+ if (len >= INT_MAX)
+ len = INT_MAX;
val = to_be_freed = xstrndup(val + beg, len);
- //bb_error_msg("val:'%s'", val);
+ }
+ debug_printf_varexp("val:'%s'\n", val);
} else
#endif
{
- die_if_script("malformed ${%s...}", var);
+ die_if_script("malformed ${%s:...}", var);
val = "";
}
} else { /* one of "-=+?" */
@@ -5891,21 +5906,28 @@
* echo $(echo 'TEST)' BEST) TEST) BEST
* echo $(echo \(\(TEST\) BEST) ((TEST) BEST
*
- * Also adapted to eat ${var%...} constructs, since ... part
+ * Also adapted to eat ${var%...} and $((...)) constructs, since ... part
* can contain arbitrary constructs, just like $(cmd).
+ * In bash compat mode, it needs to also be able to stop on '}' or ':'
+ * for ${var:N[:M]} parsing.
*/
#define DOUBLE_CLOSE_CHAR_FLAG 0x80
-static void add_till_closing_bracket(o_string *dest, struct in_str *input, char end_ch)
+static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch)
{
+ int ch;
char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG;
- end_ch &= (DOUBLE_CLOSE_CHAR_FLAG-1);
+#if ENABLE_HUSH_BASH_COMPAT
+ char end_char2 = end_ch >> 8;
+#endif
+ end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1);
+
while (1) {
- int ch = i_getch(input);
+ ch = i_getch(input);
if (ch == EOF) {
syntax_error_unterm_ch(end_ch);
/*xfunc_die(); - redundant */
}
- if (ch == end_ch) {
+ if (ch == end_ch IF_HUSH_BASH_COMPAT( || ch == end_char2)) {
if (!dbl)
break;
/* we look for closing )) of $((EXPR)) */
@@ -5947,6 +5969,7 @@
continue;
}
}
+ return ch;
}
#endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT */
@@ -6033,22 +6056,45 @@
break;
if (!isalnum(ch) && ch != '_') {
+ unsigned end_ch;
+ unsigned char last_ch;
/* handle parameter expansions
* http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
*/
if (!strchr("%#:-=+?", ch)) /* ${var<bad_char>... */
goto bad_dollar_syntax;
- /* Eat everything until closing '}' */
o_addchr(dest, ch);
+
+ /* Eat everything until closing '}' (or ':') */
+ end_ch = '}';
+ if (ENABLE_HUSH_BASH_COMPAT
+ && ch == ':'
+ && !strchr("%#:-=+?"+3, i_peek(input))
+ ) {
+ /* It's ${var:N[:M]} thing */
+ end_ch = '}' * 0x100 + ':';
+ }
+ again:
if (!BB_MMU)
pos = dest->length;
- add_till_closing_bracket(dest, input, '}');
-#if !BB_MMU
+ last_ch = add_till_closing_bracket(dest, input, end_ch);
if (as_string) {
o_addstr(as_string, dest->data + pos);
- o_addchr(as_string, '}');
+ o_addchr(as_string, last_ch);
}
-#endif
+
+ if (ENABLE_HUSH_BASH_COMPAT && (end_ch & 0xff00)) {
+ /* close the first block: */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ /* while parsing N from ${var:N[:M]}... */
+ if ((end_ch & 0xff) == last_ch) {
+ /* ...got ':' - parse the rest */
+ end_ch = '}';
+ goto again;
+ }
+ /* ...got '}', not ':' - it's ${var:N}! emulate :999999999 */
+ o_addstr(dest, "999999999");
+ }
break;
}
}
diff --git a/shell/hush_test/hush-vars/param_expand_bash_substring.right b/shell/hush_test/hush-vars/param_expand_bash_substring.right
index 6e3eb3b..53b8836 100644
--- a/shell/hush_test/hush-vars/param_expand_bash_substring.right
+++ b/shell/hush_test/hush-vars/param_expand_bash_substring.right
@@ -39,3 +39,13 @@
f::2 =|01|
f:1: =||
f:: =||
+Substrings with expressions
+f =|01234567|
+f:1+1:2+2 =|2345|
+f:-1:2+2 =|01234567|
+f:1:f =|1234567|
+f:1:$f =|1234567|
+f:1:${f} =|1234567|
+f:1:${f:3:1} =|123|
+f:1:1`echo 1`=|1|
+Done
diff --git a/shell/hush_test/hush-vars/param_expand_bash_substring.tests b/shell/hush_test/hush-vars/param_expand_bash_substring.tests
index eedd435..a80523a 100755
--- a/shell/hush_test/hush-vars/param_expand_bash_substring.tests
+++ b/shell/hush_test/hush-vars/param_expand_bash_substring.tests
@@ -1,8 +1,6 @@
-# do all of these in subshells since it's supposed to error out
-
-export var=0123456789
-
# first try some invalid patterns
+# do all of these in subshells since it's supposed to error out
+export var=0123456789
"$THIS_SH" -c 'echo ${:}'
"$THIS_SH" -c 'echo ${::}'
"$THIS_SH" -c 'echo ${:1}'
@@ -15,44 +13,56 @@
# UNFIXED BUG: this should work: "$THIS_SH" -c 'echo ${?:0}'
# now some valid ones
-"$THIS_SH" -c 'set --; echo "1 =|${1}|"'
-"$THIS_SH" -c 'set --; echo "1:1 =|${1:1}|"'
-"$THIS_SH" -c 'set --; echo "1:1:2=|${1:1:2}|"'
-"$THIS_SH" -c 'set --; echo "1::2 =|${1::2}|"'
-"$THIS_SH" -c 'set --; echo "1:1: =|${1:1:}|"'
-"$THIS_SH" -c 'set --; echo "1:: =|${1::}|"'
+set --; echo "1 =|${1}|"
+set --; echo "1:1 =|${1:1}|"
+set --; echo "1:1:2=|${1:1:2}|"
+set --; echo "1::2 =|${1::2}|"
+set --; echo "1:1: =|${1:1:}|"
+set --; echo "1:: =|${1::}|"
-"$THIS_SH" -c 'set -- 0123; echo "1 =|${1}|"'
-"$THIS_SH" -c 'set -- 0123; echo "1:1 =|${1:1}|"'
-"$THIS_SH" -c 'set -- 0123; echo "1:1:2=|${1:1:2}|"'
-"$THIS_SH" -c 'set -- 0123; echo "1::2 =|${1::2}|"'
-"$THIS_SH" -c 'set -- 0123; echo "1:1: =|${1:1:}|"'
-"$THIS_SH" -c 'set -- 0123; echo "1:: =|${1::}|"'
+set -- 0123; echo "1 =|${1}|"
+set -- 0123; echo "1:1 =|${1:1}|"
+set -- 0123; echo "1:1:2=|${1:1:2}|"
+set -- 0123; echo "1::2 =|${1::2}|"
+set -- 0123; echo "1:1: =|${1:1:}|"
+set -- 0123; echo "1:: =|${1::}|"
-"$THIS_SH" -c 'unset f; echo "f =|$f|"'
-"$THIS_SH" -c 'unset f; echo "f:1 =|${f:1}|"'
-"$THIS_SH" -c 'unset f; echo "f:1:2=|${f:1:2}|"'
-"$THIS_SH" -c 'unset f; echo "f::2 =|${f::2}|"'
-"$THIS_SH" -c 'unset f; echo "f:1: =|${f:1:}|"'
-"$THIS_SH" -c 'unset f; echo "f:: =|${f::}|"'
+unset f; echo "f =|$f|"
+unset f; echo "f:1 =|${f:1}|"
+unset f; echo "f:1:2=|${f:1:2}|"
+unset f; echo "f::2 =|${f::2}|"
+unset f; echo "f:1: =|${f:1:}|"
+unset f; echo "f:: =|${f::}|"
-"$THIS_SH" -c 'f=; echo "f =|$f|"'
-"$THIS_SH" -c 'f=; echo "f:1 =|${f:1}|"'
-"$THIS_SH" -c 'f=; echo "f:1:2=|${f:1:2}|"'
-"$THIS_SH" -c 'f=; echo "f::2 =|${f::2}|"'
-"$THIS_SH" -c 'f=; echo "f:1: =|${f:1:}|"'
-"$THIS_SH" -c 'f=; echo "f:: =|${f::}|"'
+f=; echo "f =|$f|"
+f=; echo "f:1 =|${f:1}|"
+f=; echo "f:1:2=|${f:1:2}|"
+f=; echo "f::2 =|${f::2}|"
+f=; echo "f:1: =|${f:1:}|"
+f=; echo "f:: =|${f::}|"
-"$THIS_SH" -c 'f=a; echo "f =|$f|"'
-"$THIS_SH" -c 'f=a; echo "f:1 =|${f:1}|"'
-"$THIS_SH" -c 'f=a; echo "f:1:2=|${f:1:2}|"'
-"$THIS_SH" -c 'f=a; echo "f::2 =|${f::2}|"'
-"$THIS_SH" -c 'f=a; echo "f:1: =|${f:1:}|"'
-"$THIS_SH" -c 'f=a; echo "f:: =|${f::}|"'
+f=a; echo "f =|$f|"
+f=a; echo "f:1 =|${f:1}|"
+f=a; echo "f:1:2=|${f:1:2}|"
+f=a; echo "f::2 =|${f::2}|"
+f=a; echo "f:1: =|${f:1:}|"
+f=a; echo "f:: =|${f::}|"
-"$THIS_SH" -c 'f=0123456789; echo "f =|$f|"'
-"$THIS_SH" -c 'f=0123456789; echo "f:1 =|${f:1}|"'
-"$THIS_SH" -c 'f=0123456789; echo "f:1:2=|${f:1:2}|"'
-"$THIS_SH" -c 'f=0123456789; echo "f::2 =|${f::2}|"'
-"$THIS_SH" -c 'f=0123456789; echo "f:1: =|${f:1:}|"'
-"$THIS_SH" -c 'f=0123456789; echo "f:: =|${f::}|"'
+f=0123456789; echo "f =|$f|"
+f=0123456789; echo "f:1 =|${f:1}|"
+f=0123456789; echo "f:1:2=|${f:1:2}|"
+f=0123456789; echo "f::2 =|${f::2}|"
+f=0123456789; echo "f:1: =|${f:1:}|"
+f=0123456789; echo "f:: =|${f::}|"
+
+echo "Substrings with expressions"
+f=01234567; echo 'f '"=|$f|"
+f=01234567; echo 'f:1+1:2+2 '"=|${f:1+1:2+2}|"
+f=01234567; echo 'f:-1:2+2 '"=|${f:-1:2+2}|"
+f=01234567; echo 'f:1:f '"=|${f:1:f}|"
+f=01234567; echo 'f:1:$f '"=|${f:1:$f}|"
+f=01234567; echo 'f:1:${f} '"=|${f:1:${f}}|"
+f=01234567; echo 'f:1:${f:3:1} '"=|${f:1:${f:3:1}}|"
+f=01234567; echo 'f:1:1`echo 1`'"=|${f:1:`echo 1`}|"
+
+echo Done