* ap_exr: Add replace(string, from, to) function.

Provide better token names for error messages Use either human readable names or the exact spelling from the BNF from the docs.

Limit recursion in ap_expr evaluation to avoid unbounded stack usage * evaluate chains of ||, &&, and string concatenation non-recursively * limit other types of recursion to 20 levels * avoid some string copies if concatenating more than 2 strings

Improve error message by removing 'unexpected T_ERROR' in one case.

Do proper length checks in the expression scanner. This allows to remove the 8K length limit for expressions. Strings/Regexs in an expression are still limited to 8K, though.

Add string valued expressions to ap_expr, do some API cleanup - add possibility to have expressions that evaluate to a string and not to a boolean value - modify ap_expr_parse_cmd() interface to support this and make it more convenient to use in general - rename AP_EXPR_FLAGS_* to AP_EXPR_FLAG_* for consistency

Rename ap_expr's typedef names: ap_expr -> ap_expr_t ap_expr_parse_ctx -> ap_expr_parse_ctx_t ap_expr_eval_ctx -> ap_expr_eval_ctx_t ap_expr_lookup_fn -> ap_expr_lookup_fn_t ap_expr_node_op -> ap_expr_node_op_e

- add -ipmatch, -str(c)match, -fnmatch, -R operators to ap_expr - allow lookup function to pre-parse string constant arguments (used for subnet masks so far) - various bug fixes for binary operators - do strdup() for error messages created on the stack to avoid corruption

Fix some Windows build issues

ap_expr related fixes/enhancements: - implement regex backreferences and make them available for setting envvars in SetEnvIfExpr - implement nested function calls in %-syntax: %{func1:%{func2:arg}} - actually implement evaluation of concatenation operator (oops...) - Fix <If ... > treating an internal error as success

Replace ap_expr with a parser derived from mod_ssl's parser. Make mod_ssl use the new parser. Rework ap_expr's public interface and provide hooks for modules to add variables and functions. The Netware and Windows build files still need to be adjusted