Conditional statements.

diff --git a/configure.1.pl b/configure.1.pl
index c4520676fe76e4f50a8742fc2a1e2c5c83dff9a4..806f3cc8368d368bb38a14fd9eaa61561eedeeb3 100755 (executable)
--- a/configure.1.pl
+++ b/configure.1.pl
@@ -296,6 +296,31 @@
 #     $0 - the name of the setting
 #   More functions and values can be added in future versions.
 #
+# The settings can be conditional thanks to using statements like:
+#    if
+#    else
+#    endif
+# 
+# Anything after the "if" keyword is the codition to check.
+# Condition is considered true if its value is not an empty string
+# Condition is parsed the same way as a dynamic setting definition
+#
+# Conditional statements must start at from first column in the line.
+# Conditional statements can be nested
+# 
+# Example:
+#   s1: 1
+#   if $s1
+#   s3 = $s1
+#   if $s2
+#   s3 = $s2
+#   endif
+#   else
+#   s3: 0
+#   endif
+# Here the value of s3 is '1'.
+# 
+#
 # Inserting settings to source files:
 #
 # After all settings are read, the actual source is processed line by line.
@@ -980,6 +1005,8 @@ sub parse_file {
        my $parse_mode = 0;
        my $name = '';
        my $value = '';
+       my $if_depth = 0;
+       my $if_block = 0;
 
        while (defined(my $line = <$file>)) {
                $line =~ s/[\r\n]//g;
@@ -989,40 +1016,90 @@ sub parse_file {
                # new definition name: value
                if ($line =~ /^([A-Za-z0-9_\-\.]+):[ \t](.*)$/) {
                        $parse_mode = 0;
-                       $name = $1;
-                       $value = $2;
-                       $cfg{$name} = '';
-                       print_debug($depth, "STATIC DEFINE $name=$value")
+                       unless ($if_block) {
+                               $name = $1;
+                               $value = $2;
+                               $cfg{$name} = '';
+                               print_debug($depth, "STATIC DEFINE $name=$value")
+                       }
                }
                # new definition name = value
                elsif ($line =~ /^([A-Za-z0-9_\-\.]+)[ \t]*=(.*)$/) {
                        $parse_mode = 1;
-                       $name = $1;
-                       $value = $2;
-                       $cfg{$name} = '';
-                       print_debug($depth, "DYNAMIC DEFINE $name=$value")
+                       unless ($if_block) {
+                               $name = $1;
+                               $value = $2;
+                               $cfg{$name} = '';
+                               print_debug($depth, "DYNAMIC DEFINE $name=$value")
+                       }
                }
                # continued definition
                elsif ($line =~ /^[ \t](.*)$/) {
-                       $value = "\n".$1;
-                       print_debug($depth, "CONTINUE $name $value")
+                       unless ($if_block) {
+                               $value = "\n".$1;
+                               print_debug($depth, "CONTINUE $name $value")
+                       }
                }
                # include file
-               elsif ($line =~ /^include[ \t]+([^ \t](.*[^ \t])?)[ \t]*$/)
-               {
-                       my $path = parse_value($1, $depth+1, %cfg);
-                       print_debug($depth, "INCLUDE $path");
-                       %cfg = parse_file($path, $encoding, $depth+1, %cfg);
+               elsif ($line =~ /^include[ \t]+([^ \t](.*[^ \t])?)[ \t]*$/) {
+                       unless ($if_block) {
+                               my $path = parse_value($1, $depth+1, %cfg);
+                               print_debug($depth, "INCLUDE $path");
+                               %cfg = parse_file($path, $encoding, $depth+1, %cfg);
+                               $name = '';
+                               $value = '';
+                       }
+               }
+               # if
+               elsif ($line =~ /^if[ \t]+([^ \t](.*[^ \t])?)[ \t]*$/) {
+                       $if_depth += 1;
+                       unless ($if_block) {
+                               my $cond = parse_value($1, $depth+1, %cfg);
+                               print_debug($depth, "IF.$if_depth $cond");
+                               unless ($cond ne '') {
+                                       $if_block = $if_depth;
+                               }
+                       }
+                       $name = '';
+                       $value = '';
+               }
+               # endif
+               elsif ($line =~ /^endif([ \t].*)?$/) {
+                       my $_if_depth = $if_depth;
+                       if ($if_depth > 0) {
+                               $if_depth -= 1;
+                       }
+                       if ($if_depth < $if_block) {
+                               $if_block = 0;
+                       }
+                       unless ($if_block) {
+                               print_debug($depth, "ENDIF.$_if_depth");
+                       }
                        $name = '';
                        $value = '';
                }
+               # else
+               elsif ($line =~ /^else([ \t].*)?$/) {
+                       unless ($if_block) {
+                               $if_block = $if_depth;
+                               print_debug($depth, "ELSE.$if_depth");
+                       }
+                       elsif ($if_depth == $if_block) {
+                               $if_block = 0;
+                               print_debug($depth, "ELSE.$if_depth");
+                       }
+                       $name = '';
+                       $value = '';
+               }
+               # no el(s)if at this point
+               
                # other line, not understood
                else {
                        $name = '';
                        $value = '';
                }
                
-               if ($name ne '') {
+               if (($name ne '') and (not $if_block)) {
                        if ($parse_mode != 0) {
                                $value = parse_value($value, $depth+1, %cfg);
                        }