[gen.sh] add backlinks [reading] finish voluspá

gen.sh

@@ -26,6 +26,7 @@ for file in site-src/*; do
         cp $file $tmp
     fi
 
+    # last changed section
     if git log | grep "\w*\[$bn\]" > /dev/null; then
         git log --grep="\[$bn\]" --format="%as:%s" \
             | sed "s/\[.*\]//g" \
@@ -33,6 +34,18 @@ for file in site-src/*; do
             | sed "s/$/\n/g" >> $tmp
     fi
 
+    # backlinks
+    incoming=$(grep -i "{$bn}\|{$bn " site-src/* \
+        | sed "s/\..*$//g" \
+        | sed "s/^.*\///g" \
+        | sed "s/^/{/g" \
+        | sed "s/$/}/g" \
+        | tr '\n' ' ' \
+        | sed "s/$/\n\n/g")
+    if [ ! -z "$incoming" ]; then
+        printf "\n_Incoming:_ $incoming\n" >> $tmp
+    fi
+
     ./format $tmp site/$bn.html
     rm $tmp
 done

site-src/reading.wtn

@@ -6,6 +6,10 @@ _SICP_
 
 Following is a list of various texts I've read.
 
+** 2022
+
+_Vǫluspá_
+
 ** 2021
 
 _The Three-Body Problem_, 刘慈欣 (Cixin Liu)