diff options
Diffstat (limited to 'grep.c')
| -rw-r--r-- | grep.c | 8 |
1 files changed, 6 insertions, 2 deletions
@@ -54,6 +54,8 @@ static struct grep_expr *compile_pattern_atom(struct grep_pat **list) struct grep_expr *x; p = *list; + if (!p) + return NULL; switch (p->token) { case GREP_PATTERN: /* atom */ case GREP_PATTERN_HEAD: @@ -66,8 +68,6 @@ static struct grep_expr *compile_pattern_atom(struct grep_pat **list) case GREP_OPEN_PAREN: *list = p->next; x = compile_pattern_or(list); - if (!x) - return NULL; if (!*list || (*list)->token != GREP_CLOSE_PAREN) die("unmatched parenthesis"); *list = (*list)->next; @@ -83,6 +83,8 @@ static struct grep_expr *compile_pattern_not(struct grep_pat **list) struct grep_expr *x; p = *list; + if (!p) + return NULL; switch (p->token) { case GREP_NOT: if (!p->next) @@ -361,6 +363,8 @@ static int match_expr_eval(struct grep_opt *o, { int h = 0; + if (!x) + die("Not a valid grep expression"); switch (x->node) { case GREP_NODE_ATOM: h = match_one_pattern(o, x->u.atom, bol, eol, ctx); |