1 files changed, 116 insertions, 0 deletions
diff --git a/lib/trace-cmd/trace-compress-zlib.c b/lib/trace-cmd/trace-compress-zlib.c
new file mode 100644
index 00000000..413a0764
--- /dev/null
+++ b/lib/trace-cmd/trace-compress-zlib.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (C) 2021, VMware, Tzvetomir Stoyanov tz.stoyanov@gmail.com>
+ *
+ */
+#include <stdlib.h>
+#include <dlfcn.h>
+#include <zlib.h>
+#include <errno.h>
+
+#include "trace-cmd-private.h"
+
+#define __ZLIB_NAME		"zlib"
+#define __ZLIB_WEIGTH		10
+
+static int zlib_compress(void *ctx, const void *in, int in_bytes, void *out, int out_bytes)
+{
+	unsigned long obytes = out_bytes;
+	int ret;
+
+	ret = compress2((unsigned char *)out, &obytes,
+			(unsigned char *)in, (unsigned long)in_bytes, Z_BEST_COMPRESSION);
+	switch (ret) {
+	case Z_OK:
+		return obytes;
+	case Z_BUF_ERROR:
+		errno = -ENOBUFS;
+		break;
+	case Z_MEM_ERROR:
+		errno = -ENOMEM;
+		break;
+	case Z_STREAM_ERROR:
+		errno = -EINVAL;
+		break;
+	case Z_ERRNO:
+		break;
+	default:
+		errno = -EFAULT;
+		break;
+	}
+
+	return -1;
+}
+
+static int zlib_decompress(void *ctx, const void *in, int in_bytes, void *out, int out_bytes)
+{
+	unsigned long obytes = out_bytes;
+	int ret;
+
+	ret = uncompress((unsigned char *)out, &obytes,
+			 (unsigned char *)in, (unsigned long)in_bytes);
+	switch (ret) {
+	case Z_OK:
+		return obytes;
+	case Z_BUF_ERROR:
+		errno = -ENOBUFS;
+		break;
+	case Z_MEM_ERROR:
+		errno = -ENOMEM;
+		break;
+	case Z_DATA_ERROR:
+		errno = -EINVAL;
+		break;
+	case Z_ERRNO:
+		break;
+	default:
+		errno = -EFAULT;
+		break;
+	}
+
+	return -1;
+}
+
+static unsigned int zlib_compress_bound(void *ctx, unsigned int in_bytes)
+{
+	return compressBound(in_bytes);
+}
+
+static bool zlib_is_supported(const char *name, const char *version)
+{
+	const char *zver;
+
+	if (!name)
+		return false;
+	if (strlen(name) != strlen(__ZLIB_NAME) || strcmp(name, __ZLIB_NAME))
+		return false;
+
+	if (!version)
+		return true;
+
+	zver = zlibVersion();
+	if (!zver)
+		return false;
+
+	/* Compare the major version number */
+	if (atoi(version) <= atoi(zver))
+		return true;
+
+	return false;
+}
+
+int tracecmd_zlib_init(void)
+{
+	struct tracecmd_compression_proto proto;
+
+	memset(&proto, 0, sizeof(proto));
+	proto.name = __ZLIB_NAME;
+	proto.version = zlibVersion();
+	proto.weight = __ZLIB_WEIGTH;
+	proto.compress = zlib_compress;
+	proto.uncompress = zlib_decompress;
+	proto.is_supported = zlib_is_supported;
+	proto.compress_size = zlib_compress_bound;
+
+	return tracecmd_compress_proto_register(&proto);
+}