Support for zero-length options in config files.

See RT ticket #17029 for more.

diff --git a/RELNOTES b/RELNOTES
index ef8cf5a2c2b028af77f7f87e02460e166989c7c5..e663d6df91371531feb972205f1df825dd8ce8da 100644 (file)
--- a/RELNOTES
+++ b/RELNOTES
@@ -76,6 +76,10 @@ suggested fixes to <dhcp-users@isc.org>.
   the DHCPv6 client configuration.  'send dhcp6.oro' is no longer
   necessary.
 
+- Bug fixed where configuration file parsing did not work with 
+  zero-length options; this made it impossible to set the 
+  rapid-commit option.
+
                        Changes since 4.0.0a1
 
 - Bug in octal parsing fixed. Thanks to Bernd Fuhrmann for the report

diff --git a/common/parse.c b/common/parse.c
index 4d180c11f27ffe665db477c1a49c7ebdd2717e7e..d9f01a8ad5430cf69a8278dc51b6b68cf13b2183 100644 (file)
--- a/common/parse.c
+++ b/common/parse.c
@@ -4825,7 +4825,7 @@ struct option *option;
                  * not an array of pairs of IP addresses, or something like
                  * that.
                  */
-               int uniform = option -> format [1] == 'A';
+               int uniform = 0;
 
              and_again:
                /* Set fmt to start of format for 'A' and one char back
@@ -4837,9 +4837,10 @@ struct option *option;
                        fmt = option->format;
 
                /* 'a' means always uniform */
-               uniform |= (fmt [1] == 'a');
+               if ((fmt[0] != '\0') && (tolower(fmt[1]) == 'a')) 
+                       uniform = 1;
 
-               for ( ; *fmt; fmt++) {
+               do {
                        if ((*fmt == 'A') || (*fmt == 'a'))
                                break;
                        if (*fmt == 'o')
@@ -4860,7 +4861,12 @@ struct option *option;
                        }
                         if (tmp)
                                expression_dereference (&tmp, MDL);
-               }
+
+                       if (*fmt != '\0')
+                               fmt++;
+
+               } while (*fmt != '\0');
+
                if ((*fmt == 'A') || (*fmt == 'a')) {
                        token = peek_token (&val, (unsigned *)0, cfile);
                        /* Comma means: continue with next element in array */
@@ -4904,13 +4910,16 @@ int parse_option_statement (result, cfile, lookups, option, op)
        int lose;
 
        token = peek_token (&val, (unsigned *)0, cfile);
-       if (token == SEMI) {
+       if ((token == SEMI) && (option->format[0] != '\0')) {
                /* Eat the semicolon... */
+               /*
+                * XXXSK: I'm not sure why we should ever get here, but we 
+                *        do during our startup. This confuses things if
+                *        we are parsing a zero-length option, so don't
+                *        eat the semicolon token in that case.
+                */
                token = next_token (&val, (unsigned *)0, cfile);
-               goto done;
-       }
-
-       if (token == EQUAL) {
+       } else if (token == EQUAL) {
                /* Eat the equals sign. */
                token = next_token (&val, (unsigned *)0, cfile);
 
@@ -4926,16 +4935,11 @@ int parse_option_statement (result, cfile, lookups, option, op)
                        }
                        return 0;
                }
-
-               /* We got a valid expression, so use it. */
-               goto done;
+       } else {
+               if (! parse_option_data(&expr, cfile, lookups, option))
+                       return 0;
        }
 
-       /* Parse the option data... */
-        if (! parse_option_data(&expr, cfile, lookups, option))
-                return 0;
-
-      done:
        if (!parse_semi (cfile))
                return 0;
        if (!executable_statement_allocate (result, MDL))
@@ -5192,6 +5196,17 @@ int parse_option_token (rv, cfile, fmt, expr, uniform, lookups)
                        return 0;
                break;
 
+             case '\0': /* Zero-length option. */
+               buf[0] = '\0';
+               if (!make_const_data(&t,        /* expression */
+                                    buf,       /* buffer */ 
+                                    0,         /* length */ 
+                                    0,         /* terminated */ 
+                                    1,         /* allocate */ 
+                                    MDL)) 
+                       return 0;
+               break;
+
              default:
                parse_warn (cfile, "Bad format %c in parse_option_token.",
                            **fmt);