# fuzz/Makefile.fuzz - out-of-tree libFuzzer build for the pg_tre regex parser.
#
# Usage:
#   cd fuzz
#   make -f Makefile.fuzz
#   ./pg_tre_fuzz corpus -max_total_time=900 -rss_limit_mb=2048 -detect_leaks=0
#
# Requires: clang with libFuzzer support (clang 12+).

PG_CONFIG ?= $(HOME)/.pgrx/18.3/pgrx-install/bin/pg_config

ifeq ($(shell test -x $(PG_CONFIG) && echo yes),yes)
PG_INCLUDEDIR_SERVER := $(shell $(PG_CONFIG) --includedir-server)
PG_INCLUDEDIR        := $(shell $(PG_CONFIG) --includedir)
PG_LIBDIR            := $(shell $(PG_CONFIG) --libdir)
else
$(error PG_CONFIG=$(PG_CONFIG) is not executable. Set PG_CONFIG to a valid pg_config path.)
endif

CC := clang

# libFuzzer + ASan + symbols + frame pointers for useful stack traces.
CFLAGS := -fsanitize=fuzzer,address -g -O1 -fno-omit-frame-pointer

# Real PG18 headers come from the server include tree (backend) plus the
# internal include tree (postgres_fe.h, c.h, port.h).
CFLAGS += -I$(PG_INCLUDEDIR_SERVER)
CFLAGS += -I$(PG_INCLUDEDIR)/internal
CFLAGS += -I../include
CFLAGS += -I../vendor/tre/lib

# PostgreSQL-compatible warnings, minus the ones clang doesn't support.
CFLAGS += -Wall -Wmissing-prototypes -Wpointer-arith
CFLAGS += -Wendif-labels -Wmissing-format-attribute
CFLAGS += -Wcast-function-type -Wformat-security
CFLAGS += -fno-strict-aliasing -fwrapv

# Some pg_tre / vendor sources still mix decls and statements.
CFLAGS += -Wno-declaration-after-statement

# Define PG_TRE_FUZZ to guard PostgreSQL-only code paths.
CFLAGS += -DPG_TRE_FUZZ

# libpgcommon supplies palloc/palloc0/pfree/repalloc, the StringInfo
# routines, pg_utf_mblen_private, psprintf, pstrdup, etc.  libpgport
# supplies pg_snprintf, pg_fprintf, pg_strerror, etc.  Standard system
# libs round it out.
PG_LIBS := $(PG_LIBDIR)/libpgcommon.a $(PG_LIBDIR)/libpgport.a
LDLIBS  := $(PG_LIBS) -lz -lm -lpthread

# Source files compiled into the fuzz binary.
QUERY_SRCS := ../src/query/parser.c \
              ../src/query/tokens.c \
              ../src/query/regex_ast.c \
              ../src/query/extract.c \
              ../src/query/tiling.c \
              ../src/query/uleven.c \
              ../src/query/tre_grammar.c \
              ../src/query/trigram.c

UTIL_SRCS := ../src/util/hash.c \
             ../src/util/utf8.c

FUZZ_SRCS := parse_regex_fuzz.c pg_backend_stub.c

ALL_SRCS := $(QUERY_SRCS) $(UTIL_SRCS) $(FUZZ_SRCS)
OBJS     := $(ALL_SRCS:.c=.o)

TARGET := pg_tre_fuzz

GRAMMAR_FILE := ../src/query/tre_grammar.c
ifeq ($(wildcard $(GRAMMAR_FILE)),)
$(error $(GRAMMAR_FILE) not found. Run 'make' in the parent directory first to generate the parser.)
endif

all: $(TARGET)

$(TARGET): $(OBJS)
	$(CC) $(CFLAGS) -o $@ $^ $(LDLIBS)

%.o: %.c
	$(CC) $(CFLAGS) -c -o $@ $<

clean:
	rm -f $(TARGET) $(OBJS)
	rm -f *.log crash-* leak-* oom-* slow-*

.PHONY: all clean