Provides hints to the fuzzing engine about inputs that might trigger unique code paths. Each fuzz target may have a

corresponding `.dict` file. For information about dictionary syntax, refer to

the [LibFuzzer documentation on the subject](https://llvm.org/docs/LibFuzzer.html#dictionaries).

**Things to Know**:

- OSS-Fuzz loads dictionary files per fuzz target if one exists with the same name, all others are ignored.

- Most entries in the dictionary files found here are escaped hex or Unicode values that were recommended by the fuzzing

engine after previous runs.

- A default set of dictionary entries are created for all fuzz targets as part of the build process, regardless of an

existing file here.

- Development or updates to dictionaries should reflect the varied formats and edge cases relevant to the

functionalities under test.

- Example dictionaries (some of which are used to build the default dictionaries mentioned above) can be found here:

- [AFL++ dictionary repository](https://github.com/AFLplusplus/AFLplusplus/tree/stable/dictionaries#readme)

- [Google/fuzzing dictionary repository](https://github.com/google/fuzzing/tree/master/dictionaries)

SEED_DATA_DIR="$SRC/seed_data"

find "$SEED_DATA_DIR" \( -name '*_seed_corpus.zip' -o -name '*.options' -o -name '*.dict' \) \

! \( -name '__base.*' \) -exec printf 'Copying: %s\n' {} \; \

common_base_dictionary_filename="$SEED_DATA_DIR/__base.dict"

if [[ -r "$common_base_dictionary_filename" ]]; then

# Strip the `.py` extension from the filename and replace it with `.dict`.

fuzz_harness_dictionary_filename="$(basename "$fuzz_harness" .py).dict"

output_file="$OUT/$fuzz_harness_dictionary_filename"

printf 'Appending %s to %s\n' "$common_base_dictionary_filename" "$output_file"

if [[ -s "$output_file" ]]; then

# If a dictionary file for this fuzzer already exists and is not empty,

# we append a new line to the end of it before appending any new entries.

#

# LibFuzzer will happily ignore multiple empty lines in a dictionary but fail with an error

# if any single line has incorrect syntax (e.g., if we accidentally add two entries to the same line.)

# See docs for valid syntax: https://llvm.org/docs/LibFuzzer.html#id32

echo >>"$output_file"

fi

cat "$common_base_dictionary_filename" >>"$output_file"

fi

for cmd in python3 git wget rsync; do

SEED_DATA_DIR="$SRC/seed_data"

mkdir -p "$SEED_DATA_DIR"

target_file="$1"

fetch_seed_corpora() {

# Seed corpus zip files are hosted in a separate repository to avoid additional bloat in this repo.

git clone --depth 1 https://github.com/gitpython-developers/qa-assets.git qa-assets &&

rsync -avc qa-assets/gitpython/corpra/ "$SEED_DATA_DIR/" &&

rm -rf qa-assets # Clean up the cloned repo to keep the Docker image as slim as possible.

download_and_concatenate_common_dictionaries "$SEED_DATA_DIR/__base.dict" \

"https://raw.githubusercontent.com/google/fuzzing/master/dictionaries/utf8.dict" \

"https://raw.githubusercontent.com/google/fuzzing/master/dictionaries/url.dict"