On 09/20/2010 10:21 AM, Bruno Haible wrote:
Hi Eric,/* regex_quote converts a literal string to a regular expression that will look for this literal string. cflags can be 0 or REG_EXTENDED. If it is 0, the result is a Basic Regular Expression (BRE) <http://www.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03>. If it is REG_EXTENDED, the result is an Extended Regular Expression (ERE) <http://www.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_04>. The result is not anchored; if you want it to match only complete lines, you need to add "^" at the beginning of the result and "$" at the end of the result.Since we're already passing a flag, can we add another flag that adds the ^ and $ anchors? It's more convenient to do just one malloc (via the regex_quote) that also adds the anchors, than it is to have to manually call regex_quote_length, increment the result, malloc the space, insert the anchors, then call regex_quote_copy.It's an interesting suggestion. But frankly, the benefit of such an option is small: It's straightforward, even in C, to prepend a "^" and append a "$" to a string. In the way you describe, or through regex = xasprintf ("^%s$", regex); And adding this flag would mean that the cflags of regex_quote no longer are a subset of the flags passed to regcomp. So, for the moment (until there's more heavy demand for such a flag), I prefer to address this issue only through the comments above.
Or, rather than adding a new flag big, what about providing regex_quote_anchored as a wrapper that provides the anchors, so that the end user can choose between the one-liners of regex_quote or regex_quote_anchored?
-- Eric Blake ebl...@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org
