1 files changed, 118 insertions, 0 deletions
diff --git a/neozip/test/fuzz/fuzzer_example_small.c b/neozip/test/fuzz/fuzzer_example_small.c
new file mode 100644
index 0000000000..e59c720835
--- /dev/null
+++ b/neozip/test/fuzz/fuzzer_example_small.c
@@ -0,0 +1,118 @@
+#include <stdio.h>
+#include <assert.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;
+
+/* ===========================================================================
+ * Test deflate() with small buffers
+ */
+void test_deflate(unsigned char *compr, size_t comprLen) {
+    PREFIX3(stream) c_stream; /* compression stream */
+    int err;
+    unsigned long len = (unsigned long)dataLen;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (void *)0;
+
+    err = PREFIX(deflateInit)(&c_stream, Z_DEFAULT_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_in = (z_const unsigned char *)data;
+    c_stream.next_out = compr;
+
+    while (c_stream.total_in != len && c_stream.total_out < comprLen) {
+        c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
+        err = PREFIX(deflate)(&c_stream, Z_NO_FLUSH);
+        CHECK_ERR(err, "deflate small 1");
+    }
+    /* Finish the stream, still forcing small buffers: */
+    for (;;) {
+        c_stream.avail_out = 1;
+        err = PREFIX(deflate)(&c_stream, Z_FINISH);
+        if (err == Z_STREAM_END)
+            break;
+        CHECK_ERR(err, "deflate small 2");
+    }
+
+    err = PREFIX(deflateEnd)(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with small buffers
+ */
+void test_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 = 0;
+    d_stream.next_out = uncompr;
+
+    err = PREFIX(inflateInit)(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {
+        d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
+        err = PREFIX(inflate)(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END)
+            break;
+        CHECK_ERR(err, "inflate");
+    }
+
+    err = PREFIX(inflateEnd)(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (memcmp(uncompr, data, dataLen)) {
+        fprintf(stderr, "bad inflate\n");
+        exit(1);
+    }
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *d, size_t size) {
+    size_t comprLen = PREFIX(compressBound)(size);
+    size_t uncomprLen = size;
+    uint8_t *compr, *uncompr;
+
+    /* Discard inputs larger than 1Mb. */
+    static size_t kMaxSize = 1024 * 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_deflate(compr, comprLen);
+    test_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    free(compr);
+    free(uncompr);
+
+    /* This function must return 0. */
+    return 0;
+}