[Leptonica] Added fuzzer with seed corpus (#3702)

* Added fuzzer with seed corpus

* Removed flag

* Added license header

projects/leptonica/Dockerfile

@@ -27,4 +27,4 @@ RUN git clone https://www.cl.cam.ac.uk/~mgk25/git/jbigkit jbigkit
 RUN git clone --depth 1 https://github.com/libjpeg-turbo/libjpeg-turbo libjpeg-turbo
 RUN git clone --depth 1 https://github.com/facebook/zstd zstd
 WORKDIR leptonica
-COPY build.sh pix_rotate_shear_fuzzer.cc $SRC/
+COPY build.sh pixa_recog_fuzzer.cc pix_rotate_shear_fuzzer.cc $SRC/

projects/leptonica/build.sh

@@ -117,3 +117,17 @@ $CXX $CXXFLAGS -std=c++11 -I"$WORK/include" \
   "$WORK/lib/libz.a" \
   $LIB_FUZZING_ENGINE
 
+$CXX $CXXFLAGS -std=c++11 -I"$WORK/include" \
+  "$SRC/pixa_recog_fuzzer.cc" -o "$OUT/pixa_recog_fuzzer" \
+  -Isrc/ \
+  "$WORK/lib/liblept.a" \
+  "$WORK/lib/libtiff.a" \
+  "$WORK/lib/libwebp.a" \
+  "$WORK/lib/libpng.a" \
+  "$WORK/lib/libjpeg.a" \
+  "$WORK/lib/libjbig.a" \
+  "$WORK/lib/libzstd.a" \
+  "$WORK/lib/libz.a" \
+  $LIB_FUZZING_ENGINE
+
+cd $SRC/leptonica/prog/recog/sets && zip pixa_recog_fuzzer_seed_corpus.zip test01.pa && mv pixa_recog_fuzzer_seed_corpus.zip /out/

projects/leptonica/pixa_recog_fuzzer.cc

@@ -0,0 +1,79 @@
+/*
+# Copyright 2020 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+*/
+
+#include "string.h"
+#include "allheaders.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+
+extern "C" int
+LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+        if(size<20) return 0;
+
+        char filename[256];
+        sprintf(filename, "/tmp/libfuzzer.pa");
+
+        FILE *fp = fopen(filename, "wb");
+        if (!fp)
+                return 0;
+        fwrite(data, size, 1, fp);
+        fclose(fp);
+
+        char      *text;
+        l_int32    histo[10];
+        PIXA      *pixa1, *pixa2, *pixa3, *pixa4;
+        L_RECOG   *recog1;
+        l_int32    i, n, ival;
+        PIX       *pix1;
+
+        pixa1 = pixaRead(filename);
+        pixa2 = pixaCreate(0);
+        pixa3 = pixaCreate(0);
+
+        n = pixaGetCount(pixa1);
+        for (i = 0; i < 10; i++)
+                histo[i] = 0;
+        for (i = 0; i < n; i++) {
+                pix1 = pixaGetPix(pixa1, i, L_COPY);
+                text = pixGetText(pix1);
+                ival = text[0] - '0';
+                if (ival == 4 || (ival == 7 && histo[7] == 2) ||
+                        (ival == 9 && histo[9] == 2)) {
+                        pixaAddPix(pixa3, pix1, L_INSERT);
+                } else {
+                        pixaAddPix(pixa2, pix1, L_INSERT);
+                        histo[ival]++;
+                }
+        }
+
+        recog1 = recogCreateFromPixa(pixa2, 0, 40, 1, 128, 1);
+        pixa4 = recogTrainFromBoot(recog1, pixa3, 0.75, 128, 1);
+
+        recogDestroy(&recog1);
+        pixaDestroy(&pixa1);
+        pixaDestroy(&pixa2);
+        pixaDestroy(&pixa3);
+        pixaDestroy(&pixa4);
+        unlink(filename);
+
+        return 0;
+}