[PATCH v3 11/16] scripts/oss-fuzz: Add general-fuzzer build script

[Alexander Bulekov]

This parses a yaml file containing general-fuzzer configs and builds a
separate oss-fuzz wrapper binary for each one, changing some
preprocessor macros for each configuration. To avoid dealing with
escaping and stringifying, convert each string into a byte-array
representation

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
---
 scripts/oss-fuzz/build_general_fuzzers.py | 69 +++++++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100755 scripts/oss-fuzz/build_general_fuzzers.py

diff --git a/scripts/oss-fuzz/build_general_fuzzers.py 
b/scripts/oss-fuzz/build_general_fuzzers.py
new file mode 100755
index 0000000000..918f1143a5
--- /dev/null
+++ b/scripts/oss-fuzz/build_general_fuzzers.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+"""
+This script creates wrapper binaries that invoke the general-device-fuzzer with
+configurations specified in a yaml config file.
+"""
+import sys
+import os
+import yaml
+import tempfile
+
+CC = ""
+TEMPLATE_FILENAME = "target_template.c"
+TEMPLATE_PATH = ""
+
+
+def usage():
+    print("Usage: CC=COMPILER {} CONFIG_PATH \
+OUTPUT_PATH_PREFIX".format(sys.argv[0]))
+    sys.exit(0)
+
+
+def str_to_c_byte_array(s):
+    """
+    Convert strings to byte-arrays so we don't worry about formatting
+    strings to play nicely with cc -DQEMU_FUZZARGS etc
+    """
+    return ','.join('0x{:02x}'.format(ord(x)) for x in s)
+
+
+def compile_wrapper(cfg, path):
+    os.system('$CC -DQEMU_FUZZ_ARGS="{fuzz_args}" \
+               -DQEMU_FUZZ_OBJECTS="{fuzz_objs}" \
+               {wrapper_template} -o {output_bin}'.format(
+                   fuzz_args=str_to_c_byte_array(cfg["args"].replace("\n", " 
")),
+                   fuzz_objs=str_to_c_byte_array(cfg["objects"].replace("\n", 
" ")),
+                   wrapper_template=TEMPLATE_PATH,
+                   output_bin=path))
+
+
+def main():
+    global CC
+    global TEMPLATE_PATH
+    global OUTPUT_BIN_NAME
+
+    if len(sys.argv) != 3:
+        usage()
+
+    cfg_path = sys.argv[1]
+    out_path = sys.argv[2]
+
+    CC = os.getenv("CC", default="cc")
+    TEMPLATE_PATH = os.path.join(os.path.dirname(__file__), TEMPLATE_FILENAME)
+    if not os.path.exists(TEMPLATE_PATH):
+        print("Error {} doesn't exist".format(TEMPLATE_PATH))
+        sys.exit(1)
+
+    with open(cfg_path, "r") as f:
+        configs = yaml.load(f)["configs"]
+    for cfg in configs:
+        assert "name" in cfg
+        assert "args" in cfg
+        assert "objects" in cfg
+        compile_wrapper(cfg, out_path + cfg["name"])
+
+
+if __name__ == '__main__':
+    main()
-- 
2.28.0