1 files changed, 137 insertions, 0 deletions
diff --git a/neozip/test/fuzz/fuzzer_example_large.c b/neozip/test/fuzz/fuzzer_example_large.c
new file mode 100644
index 0000000000..4114597218
--- /dev/null
+++ b/neozip/test/fuzz/fuzzer_example_large.c
@@ -0,0 +1,137 @@
+#include <stdio.h>
+#include <assert.h>
+#include <inttypes.h>
+
+#include "zbuild.h"
+#ifdef ZLIB_COMPAT
+#  include "zlib.h"
+#else
+#  include "zlib-ng.h"
+#endif
+
+#define CHECK_ERR(err, msg) { \
+    if (err != Z_OK) { \
+        fprintf(stderr, "%s error: %d\n", msg, err); \
+        exit(1); \
+    } \
+}
+
+static const uint8_t *data;
+static size_t dataLen;
+static alloc_func zalloc = NULL;
+static free_func zfree = NULL;
+static unsigned int diff;
+
+/* ===========================================================================
+ * Test deflate() with large buffers and dynamic change of compression level
+ */
+void test_large_deflate(unsigned char *compr, size_t comprLen, unsigned char *uncompr, size_t uncomprLen) {
+    PREFIX3(stream) c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (void *)0;
+
+    err = PREFIX(deflateInit)(&c_stream, Z_BEST_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_out = compr;
+    c_stream.avail_out = (unsigned int)comprLen;
+
+    /* At this point, uncompr is still mostly zeroes, so it should compress
+     * very well:
+     */
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (unsigned int)uncomprLen;
+    err = PREFIX(deflate)(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate large 1");
+    if (c_stream.avail_in != 0) {
+        fprintf(stderr, "deflate not greedy\n");
+        exit(1);
+    }
+
+    /* Feed in already compressed data and switch to no compression: */
+    PREFIX(deflateParams)(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
+    c_stream.next_in = compr;
+    diff = (unsigned int)(c_stream.next_out - compr);
+    c_stream.avail_in = diff;
+    err = PREFIX(deflate)(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate large 2");
+
+    /* Switch back to compressing mode: */
+    PREFIX(deflateParams)(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (unsigned int)uncomprLen;
+    err = PREFIX(deflate)(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate large 3");
+
+    err = PREFIX(deflate)(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate large should report Z_STREAM_END\n");
+        exit(1);
+    }
+    err = PREFIX(deflateEnd)(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with large buffers
+ */
+void test_large_inflate(unsigned char *compr, size_t comprLen, unsigned char *uncompr, size_t uncomprLen) {
+    int err;
+    PREFIX3(stream) d_stream; /* decompression stream */
+
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
+    d_stream.opaque = (void *)0;
+
+    d_stream.next_in = compr;
+    d_stream.avail_in = (unsigned int)comprLen;
+
+    err = PREFIX(inflateInit)(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    for (;;) {
+        d_stream.next_out = uncompr; /* discard the output */
+        d_stream.avail_out = (unsigned int)uncomprLen;
+        err = PREFIX(inflate)(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END)
+            break;
+        CHECK_ERR(err, "large inflate");
+    }
+
+    err = PREFIX(inflateEnd)(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (d_stream.total_out != 2 * uncomprLen + diff) {
+        fprintf(stderr, "bad large inflate: %" PRIu64 "\n", (uint64_t)d_stream.total_out);
+        exit(1);
+    }
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
+    size_t comprLen = 100 + 3 * size;
+    size_t uncomprLen = comprLen;
+    uint8_t *compr, *uncompr;
+
+    /* Discard inputs larger than 512Kb. */
+    static size_t kMaxSize = 512 * 1024;
+
+    if (size < 1 || size > kMaxSize)
+        return 0;
+
+    data = d;
+    dataLen = size;
+    compr = (uint8_t *)calloc(1, comprLen);
+    uncompr = (uint8_t *)calloc(1, uncomprLen);
+
+    test_large_deflate(compr, comprLen, uncompr, uncomprLen);
+    test_large_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    free(compr);
+    free(uncompr);
+
+    /* This function must return 0. */
+    return 0;
+}