Add seed parameter to entropy.sh

.github/workflows/build.yml

@@ -87,7 +87,10 @@ jobs:
     - name: Generate Entropy
       shell: bash
       run: |
-        tools/entropy.sh
+        # Get the first 8 characters of the SHA (enough for a decent seed)
+        SHA_PREFIX=$(echo "${{ github.sha }}" | cut -c 1-8)
+
+        tools/entropy.sh $((16#$SHA_PREFIX + ${{ matrix.instance }}))
 
     - name: Build
       shell: cmd

tools/entropy.sh

@@ -3,29 +3,65 @@
 # Output file
 OUTPUT_FILE="entropy.h"
 
-# Function to generate a random CamelCase string of given length
+# Function to generate a CamelCase string of given length
 generate_name() {
-    cat /dev/urandom | tr -dc 'a-z' | fold -w "$1" | head -n 1 | sed -E 's/(^|_)([a-z])/\U\2/g'
+  local seed="$1"
+  local length="$2"
+  local char_count=0
+  local random_bytes=""
+
+  while [ "$char_count" -lt "$length" ]; do
+    random_bytes+=$(od -vAn -N4 -tu4 < /dev/urandom | tr -d '[:space:]')
+    char_count=$((char_count + 1))
+  done
+
+  # Use the provided seed for the random number generation.  Crucially, re-seed bash's
+  # RANDOM for each name.
+  RANDOM="$seed"
+
+  local result=""
+  for ((i=0; i<length; i++)); do
+    # Get a pseudo-random number between 0 and 25 (inclusive)
+    local rand_index=$((RANDOM % 26))
+    # Convert to lowercase ASCII character (a=97)
+    local char_code=$((97 + rand_index))
+    # Append to the result string
+    result+=$(printf "\\$(printf '%o' "$char_code")")
+  done
+  echo "$result" | sed -E 's/(^|_)([a-z])/\U\2/g'
 }
 
+# Parse command-line arguments
+if [ "$#" -ne 1 ]; then
+  echo "Usage: $0 <seed_number>"
+  exit 1
+fi
+
+SEED="$1"
+# Initialize the random number generator with the seed
+RANDOM="$SEED"
+
 # Generate a random number of classes (between 1 and 10)
 NUM_CLASSES=$((RANDOM % 10 + 1))
 
 > "$OUTPUT_FILE"  # Clear or create the output file
 
+echo "// Seed: $SEED" > "$OUTPUT_FILE"
+echo >> "$OUTPUT_FILE"
+
 for ((i=0; i<NUM_CLASSES; i++)); do
-    CLASS_NAME="Class$(generate_name 6)"
+    CLASS_NAME="Class$(generate_name "$((SEED + i * 100))" 6)"
     echo "class $CLASS_NAME {" >> "$OUTPUT_FILE"
-    
+
     # Generate a random number of methods (between 1 and 10)
     NUM_METHODS=$((RANDOM % 10 + 1))
     for ((j=0; j<NUM_METHODS; j++)); do
-        METHOD_NAME="Function$(generate_name 8)"
-        echo "inline void $METHOD_NAME() {}" >> "$OUTPUT_FILE"
+        METHOD_NAME="Function$(generate_name "$((SEED + i * 100 + j))" 8)"
+        echo -e "\tinline void $METHOD_NAME() {}" >> "$OUTPUT_FILE"
     done
-    
+
     echo "};" >> "$OUTPUT_FILE"
-    echo >> "$OUTPUT_FILE"  # Add an empty line for readability
+    echo >> "$OUTPUT_FILE"
 done
 
 echo "Generated $NUM_CLASSES classes in $OUTPUT_FILE"