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authorMike Frysinger2009-04-09 23:00:33 +0000
committerMike Frysinger2009-04-09 23:00:33 +0000
commit57e746781c6cd836a9564299ef04d2ae4d995f1c (patch)
tree6f700223120ea64a82cc61b30146e227437da6b7 /shell
parentd68ae08cde969985e3bfcfc21a64f9c78d736fe1 (diff)
downloadbusybox-57e746781c6cd836a9564299ef04d2ae4d995f1c.zip
busybox-57e746781c6cd836a9564299ef04d2ae4d995f1c.tar.gz
dont crash if the variable we do substitution on is not set
Diffstat (limited to 'shell')
-rw-r--r--shell/hush.c26
1 files changed, 14 insertions, 12 deletions
diff --git a/shell/hush.c b/shell/hush.c
index d6f765d..ac2410c 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -2025,18 +2025,20 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
debug_printf_expand("%s\n", val);
} else if (exp_off) {
if (exp_op == '%' || exp_op == '#') {
- /* we need to do a pattern match */
- bool zero;
- char *loc;
- scan_t scan = pick_scan(exp_op, *exp_word, &zero);
- if (exp_op == *exp_word) /* ## or %% */
- ++exp_word;
- val = dyn_val = xstrdup(val);
- loc = scan(dyn_val, exp_word, zero);
- if (zero)
- val = loc;
- else
- *loc = '\0';
+ if (val) {
+ /* we need to do a pattern match */
+ bool zero;
+ char *loc;
+ scan_t scan = pick_scan(exp_op, *exp_word, &zero);
+ if (exp_op == *exp_word) /* ## or %% */
+ ++exp_word;
+ val = dyn_val = xstrdup(val);
+ loc = scan(dyn_val, exp_word, zero);
+ if (zero)
+ val = loc;
+ else
+ *loc = '\0';
+ }
} else {
/* we need to do an expansion */
int exp_test = (!val || (exp_null && !val[0]));