regex: fix character class repetitions

Internally regcomp needs to copy some iteration nodes before
translating the AST into TNFA representation.

Literal nodes were not copied correctly: the class type and list
of negated class types were not copied so classes were ignored
(in the non-negated case an ignored char class caused the literal
to match everything).

This affects iterations when the upper bound is finite, larger
than one or the lower bound is larger than one. So eg. the EREs

 [[:digit:]]{2}
 [^[:space:]ab]{1,4}

were treated as

 .{2}
 [^ab]{1,4}

The fix is done with minimal source modification to copy the
necessary fields, but the AST preparation and node handling
code of tre will need to be cleaned up for clarity.

diff --git a/src/regex/regcomp.c b/src/regex/regcomp.c
index dfa9727c5f3601aaa27e864467bd818f72f89127..978dd87f33912d7c097e3cc281bd1479070d7e99 100644 (file)
--- a/src/regex/regcomp.c
+++ b/src/regex/regcomp.c
@@ -1700,6 +1700,11 @@ tre_copy_ast(tre_mem_t mem, tre_stack_t *stack, tre_ast_node_t *ast,
                *result = tre_ast_new_literal(mem, min, max, pos);
                if (*result == NULL)
                  status = REG_ESPACE;
+               else {
+                 tre_literal_t *p = (*result)->obj;
+                 p->class = lit->class;
+                 p->neg_classes = lit->neg_classes;
+               }
 
                if (pos > *max_pos)
                  *max_pos = pos;