bug in token.c ?

25 Jul 2011

      Hello List,

I believe I found a bug in token.c, more precisely in
static FR_TOKEN getthing(...)

The exact point is the part handling backslahes:

--- cut ---

if (quote && (*p == '\\')) {
			p++;

			switch(*p) {
				case 'r':
					*s++ = '\r';
					break;
				case 'n':
					*s++ = '\n';
					break;
				case 't':
					*s++ = '\t';
					break;
				case '\0':
					*s++ = '\\';
					p--; /* force EOS */
					break;
				default:
					if (*p >= '0' && *p <= '9' &&
					    sscanf(p, "%3o", &x) == 1) {
						*s++ = x;
						p += 2;
					} else
						*s++ = *p;
					break;
			}
			p++;
			continue;
		}

--- cut ---

This piece of code removes all backslashes from the input string, which 
gives incorrect results when parsing strings for regular expressions 
with excaped characters. At a first glance, the fix is easy:

--- cut ---

				default:
					if (*p >= '0' && *p <= '9' &&
					    sscanf(p, "%3o", &x) == 1) {
						*s++ = x;
						p += 2;
					} else {
						*s++ = '\\'; /* copy the '\' too */
						*s++ = *p;
					}
					break;

--- cut ---

which solves the problem.
On the other hand, I'm not sure if it breaks anything else. Is there a 
reason to remove backslashes on purpose? Or is this really a bug?

Regards,
Oliver Schröder