Repo created

TMessagesProj/jni/voip/tgcalls/utils/gzip.cpp

@@ -0,0 +1,183 @@
+#include "utils/gzip.h"
+
+#include <zlib.h>
+
+#include "rtc_base/copy_on_write_buffer.h"
+
+namespace tgcalls {
+namespace {
+
+using uint = decltype(z_stream::avail_in);
+
+} // namespace
+
+bool isGzip(std::vector<uint8_t> const &data) {
+    if (data.size() < 2) {
+        return false;
+    }
+
+    if ((data[0] == 0x1f && data[1] == 0x8b) || (data[0] == 0x78 && data[1] == 0x9c)) {
+        return true;
+    } else {
+        return false;
+    }
+}
+
+absl::optional<std::vector<uint8_t>> gzipData(std::vector<uint8_t> const &data) {
+    z_stream stream;
+    stream.zalloc = Z_NULL;
+    stream.zfree = Z_NULL;
+    stream.opaque = Z_NULL;
+    stream.avail_in = (uint)data.size();
+    stream.next_in = (Bytef *)(void *)data.data();
+    stream.total_out = 0;
+    stream.avail_out = 0;
+
+    static const uint ChunkSize = 16384;
+
+    std::vector<uint8_t> output;
+    int compression = 9;
+    if (deflateInit2(&stream, compression, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY) == Z_OK) {
+        output.resize(ChunkSize);
+
+        while (stream.avail_out == 0) {
+            if (stream.total_out >= output.size()) {
+                output.resize(output.size() + ChunkSize);
+            }
+            stream.next_out = (uint8_t *)output.data() + stream.total_out;
+            stream.avail_out = (uInt)(output.size() - stream.total_out);
+            deflate(&stream, Z_FINISH);
+        }
+        deflateEnd(&stream);
+        output.resize(stream.total_out);
+    }
+
+    return output;
+}
+
+absl::optional<std::vector<uint8_t>> gunzipData(std::vector<uint8_t> const &data, size_t sizeLimit) {
+    if (!isGzip(data)) {
+        return absl::nullopt;
+    }
+
+    z_stream stream;
+    stream.zalloc = Z_NULL;
+    stream.zfree = Z_NULL;
+    stream.avail_in = (uint)data.size();
+    stream.next_in = (Bytef *)data.data();
+    stream.total_out = 0;
+    stream.avail_out = 0;
+
+    std::vector<uint8_t> output;
+    if (inflateInit2(&stream, 47) == Z_OK) {
+        int status = Z_OK;
+        output.resize(data.size() * 2);
+        while (status == Z_OK) {
+            if (sizeLimit > 0 && stream.total_out > sizeLimit) {
+                return absl::nullopt;
+            }
+
+            if (stream.total_out >= output.size()) {
+                output.resize(output.size() + data.size() / 2);
+            }
+            stream.next_out = (uint8_t *)output.data() + stream.total_out;
+            stream.avail_out = (uInt)(output.size() - stream.total_out);
+            status = inflate(&stream, Z_SYNC_FLUSH);
+        }
+        if (inflateEnd(&stream) == Z_OK) {
+            if (status == Z_STREAM_END) {
+                output.resize(stream.total_out);
+            } else if (sizeLimit > 0 && output.size() > sizeLimit) {
+                return absl::nullopt;
+            }
+        }
+    }
+
+    return output;
+}
+
+}
+
+/*bool TGIsGzippedData(NSData *data) {
+    const UInt8 *bytes = (const UInt8 *)data.bytes;
+    return data.length >= 2 && ((bytes[0] == 0x1f && bytes[1] == 0x8b) || (bytes[0] == 0x78 && bytes[1] == 0x9c));
+}
+
+NSData *TGGZipData(NSData *data, float level) {
+    if (data.length == 0 || TGIsGzippedData(data)) {
+        return data;
+    }
+
+    z_stream stream;
+    stream.zalloc = Z_NULL;
+    stream.zfree = Z_NULL;
+    stream.opaque = Z_NULL;
+    stream.avail_in = (uint)data.length;
+    stream.next_in = (Bytef *)(void *)data.bytes;
+    stream.total_out = 0;
+    stream.avail_out = 0;
+
+    static const NSUInteger ChunkSize = 16384;
+
+    NSMutableData *output = nil;
+    int compression = (level < 0.0f) ? Z_DEFAULT_COMPRESSION : (int)(roundf(level * 9));
+    if (deflateInit2(&stream, compression, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY) == Z_OK) {
+        output = [NSMutableData dataWithLength:ChunkSize];
+        while (stream.avail_out == 0) {
+            if (stream.total_out >= output.length) {
+                output.length += ChunkSize;
+            }
+            stream.next_out = (uint8_t *)output.mutableBytes + stream.total_out;
+            stream.avail_out = (uInt)(output.length - stream.total_out);
+            deflate(&stream, Z_FINISH);
+        }
+        deflateEnd(&stream);
+        output.length = stream.total_out;
+    }
+
+    return output;
+}
+
+NSData * _Nullable TGGUnzipData(NSData *data, uint sizeLimit)
+{
+    if (data.length == 0 || !TGIsGzippedData(data)) {
+        return nil;
+    }
+
+    z_stream stream;
+    stream.zalloc = Z_NULL;
+    stream.zfree = Z_NULL;
+    stream.avail_in = (uint)data.length;
+    stream.next_in = (Bytef *)data.bytes;
+    stream.total_out = 0;
+    stream.avail_out = 0;
+
+    NSMutableData *output = nil;
+    if (inflateInit2(&stream, 47) == Z_OK) {
+        int status = Z_OK;
+        output = [NSMutableData dataWithCapacity:data.length * 2];
+        while (status == Z_OK) {
+            if (sizeLimit > 0 && stream.total_out > sizeLimit) {
+                return nil;
+            }
+
+            if (stream.total_out >= output.length) {
+                output.length = output.length + data.length / 2;
+            }
+            stream.next_out = (uint8_t *)output.mutableBytes + stream.total_out;
+            stream.avail_out = (uInt)(output.length - stream.total_out);
+            status = inflate(&stream, Z_SYNC_FLUSH);
+        }
+        if (inflateEnd(&stream) == Z_OK) {
+            if (status == Z_STREAM_END) {
+                output.length = stream.total_out;
+            } else if (sizeLimit > 0 && output.length > sizeLimit) {
+                return nil;
+            }
+        }
+    }
+
+    return output;
+}
+
+*/

TMessagesProj/jni/voip/tgcalls/utils/gzip.h

@@ -0,0 +1,16 @@
+#ifndef TGCALLS_UTILS_GZIP_H
+#define TGCALLS_UTILS_GZIP_H
+
+#include <absl/types/optional.h>
+#include <cstdint>
+#include <vector>
+
+namespace tgcalls {
+
+bool isGzip(std::vector<uint8_t> const &data);
+absl::optional<std::vector<uint8_t>> gzipData(std::vector<uint8_t> const &data);
+absl::optional<std::vector<uint8_t>> gunzipData(std::vector<uint8_t> const &data, size_t sizeLimit);
+
+}
+
+#endif // TGCALLS_UTILS_GZIP_H