D5799 Part 2: ZStd support

13 files changed, 681 insertions, 73 deletions

diff --git a/build_files/cmake/Modules/FindZstd.cmake b/build_files/cmake/Modules/FindZstd.cmake
new file mode 100644
index 00000000000..84606d01f44
--- /dev/null
+++ b/build_files/cmake/Modules/FindZstd.cmake
@@ -0,0 +1,66 @@
+# - Find Zstd library
+# Find the native Zstd includes and library
+# This module defines
+#  ZSTD_INCLUDE_DIRS, where to find zstd.h, Set when
+#                     ZSTD_INCLUDE_DIR is found.
+#  ZSTD_LIBRARIES, libraries to link against to use Zstd.
+#  ZSTD_ROOT_DIR, The base directory to search for Zstd.
+#                 This can also be an environment variable.
+#  ZSTD_FOUND, If false, do not try to use Zstd.
+#
+# also defined, but not for general use are
+#  ZSTD_LIBRARY, where to find the Zstd library.
+
+#=============================================================================
+# Copyright 2019 Blender Foundation.
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+
+# If ZSTD_ROOT_DIR was defined in the environment, use it.
+IF(NOT ZSTD_ROOT_DIR AND NOT $ENV{ZSTD_ROOT_DIR} STREQUAL "")
+  SET(ZSTD_ROOT_DIR $ENV{ZSTD_ROOT_DIR})
+ENDIF()
+
+SET(_zstd_SEARCH_DIRS
+  ${ZSTD_ROOT_DIR}
+)
+
+FIND_PATH(ZSTD_INCLUDE_DIR
+  NAMES
+    zstd.h
+  HINTS
+    ${_zstd_SEARCH_DIRS}
+  PATH_SUFFIXES
+    include
+)
+
+FIND_LIBRARY(ZSTD_LIBRARY
+  NAMES
+    zstd
+  HINTS
+    ${_zstd_SEARCH_DIRS}
+  PATH_SUFFIXES
+    lib64 lib
+  )
+
+# handle the QUIETLY and REQUIRED arguments and set ZSTD_FOUND to TRUE if
+# all listed variables are TRUE
+INCLUDE(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(Zstd DEFAULT_MSG
+    ZSTD_LIBRARY ZSTD_INCLUDE_DIR)
+
+IF(ZSTD_FOUND)
+  SET(ZSTD_LIBRARIES ${ZSTD_LIBRARY})
+  SET(ZSTD_INCLUDE_DIRS ${ZSTD_INCLUDE_DIR})
+ENDIF()
+
+MARK_AS_ADVANCED(
+  ZSTD_INCLUDE_DIR
+  ZSTD_LIBRARY
+)
diff --git a/build_files/cmake/platform/platform_unix.cmake b/build_files/cmake/platform/platform_unix.cmake
index 7f62399ac4f..fc0c37e4c8b 100644
--- a/build_files/cmake/platform/platform_unix.cmake
+++ b/build_files/cmake/platform/platform_unix.cmake
@@ -99,6 +99,7 @@ endif()
 find_package_wrapper(JPEG REQUIRED)
 find_package_wrapper(PNG REQUIRED)
 find_package_wrapper(ZLIB REQUIRED)
+find_package_wrapper(Zstd REQUIRED)
 find_package_wrapper(Freetype REQUIRED)
 
 if(WITH_PYTHON)
diff --git a/build_files/cmake/platform/platform_win32.cmake b/build_files/cmake/platform/platform_win32.cmake
index 3773aaaffed..d44ef691d1b 100644
--- a/build_files/cmake/platform/platform_win32.cmake
+++ b/build_files/cmake/platform/platform_win32.cmake
@@ -873,3 +873,6 @@ if(WITH_HARU)
     set(WITH_HARU OFF)
   endif()
 endif()
+
+set(ZSTD_INCLUDE_DIRS ${LIBDIR}/zstd/include)
+set(ZSTD_LIBRARIES ${LIBDIR}/zstd/lib/zstd_static.lib)
diff --git a/source/blender/blenlib/BLI_fileops.h b/source/blender/blenlib/BLI_fileops.h
index 12fa73279c8..377b7bc3bc2 100644
--- a/source/blender/blenlib/BLI_fileops.h
+++ b/source/blender/blenlib/BLI_fileops.h
@@ -168,6 +168,8 @@ size_t BLI_ungzip_file_to_mem_at_pos(void *buf, size_t len, FILE *file, size_t g
     ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 bool BLI_file_magic_is_gzip(const char header[4]);
 
+bool BLI_file_magic_is_zstd(const char header[4]);
+
 size_t BLI_file_descriptor_size(int file) ATTR_WARN_UNUSED_RESULT;
 size_t BLI_file_size(const char *path) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 
diff --git a/source/blender/blenlib/BLI_filereader.h b/source/blender/blenlib/BLI_filereader.h
index dbcaa7cb1b6..8d1fa3d1596 100644
--- a/source/blender/blenlib/BLI_filereader.h
+++ b/source/blender/blenlib/BLI_filereader.h
@@ -61,7 +61,7 @@ typedef struct FileReader {
  *
  * If a FileReader is created, it has to be cleaned up and freed by calling
  * its close() function unless another FileReader has taken ownership - for example,
- * Gzip takes over the base FileReader and will clean it up when their clean() is called.
+ * Zstd and Gzip take over the base FileReader and will clean it up when their clean() is called.
  */
 
 /* Create FileReader from raw file descriptor. */
@@ -71,6 +71,8 @@ FileReader *BLI_filereader_new_mmap(int filedes) ATTR_WARN_UNUSED_RESULT;
 /* Create FileReader from a region of memory. */
 FileReader *BLI_filereader_new_memory(const void *data, size_t len) ATTR_WARN_UNUSED_RESULT
     ATTR_NONNULL();
+/* Create FileReader from applying Zstd decompression on an underlying file. */
+FileReader *BLI_filereader_new_zstd(FileReader *base) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 /* Create FileReader from applying Gzip decompression on an underlying file. */
 FileReader *BLI_filereader_new_gzip(FileReader *base) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 
diff --git a/source/blender/blenlib/CMakeLists.txt b/source/blender/blenlib/CMakeLists.txt
index d2ba9e74c90..f98d15ad08b 100644
--- a/source/blender/blenlib/CMakeLists.txt
+++ b/source/blender/blenlib/CMakeLists.txt
@@ -31,6 +31,7 @@ set(INC
 
 set(INC_SYS
   ${ZLIB_INCLUDE_DIRS}
+  ${ZSTD_INCLUDE_DIRS}
   ${FREETYPE_INCLUDE_DIRS}
   ${GMP_INCLUDE_DIRS}
 )
@@ -78,6 +79,7 @@ set(SRC
   intern/filereader_file.c
   intern/filereader_gzip.c
   intern/filereader_memory.c
+  intern/filereader_zstd.c
   intern/fnmatch.c
   intern/freetypefont.c
   intern/gsqueue.c
@@ -327,6 +329,7 @@ set(LIB
 
   ${FREETYPE_LIBRARY}
   ${ZLIB_LIBRARIES}
+  ${ZSTD_LIBRARIES}
 )
 
 if(WITH_MEM_VALGRIND)
diff --git a/source/blender/blenlib/intern/fileops.c b/source/blender/blenlib/intern/fileops.c
index 6fc2222241b..31825c69737 100644
--- a/source/blender/blenlib/intern/fileops.c
+++ b/source/blender/blenlib/intern/fileops.c
@@ -262,6 +262,33 @@ bool BLI_file_magic_is_gzip(const char header[4])
   return header[0] == 0x1f && header[1] == 0x8b && header[2] == 0x08;
 }
 
+bool BLI_file_magic_is_zstd(const char header[4])
+{
+  /* ZSTD files consist of concatenated frames, each either a Zstd frame or a skippable frame.
+   * Both types of frames start with a magic number: 0xFD2FB528 for Zstd frames and 0x184D2A5*
+   * for skippable frames, with the * being anything from 0 to F.
+   *
+   * To check whether a file is Zstd-compressed, we just check whether the first frame matches
+   * either. Seeking through the file until a Zstd frame is found would make things more
+   * complicated and the probability of a false positive is rather low anyways.
+   *
+   * Note that LZ4 uses a compatible format, so even though its compressed frames have a
+   * different magic number, a valid LZ4 file might also start with a skippable frame matching
+   * the second check here.
+   *
+   * For more details, see https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md
+   */
+
+  uint32_t magic = *((uint32_t *)header);
+  if (magic == 0xFD2FB528) {
+    return true;
+  }
+  if ((magic >> 4) == 0x184D2A5) {
+    return true;
+  }
+  return false;
+}
+
 /**
  * Returns true if the file with the specified name can be written.
  * This implementation uses access(2), which makes the check according
diff --git a/source/blender/blenlib/intern/filereader_zstd.c b/source/blender/blenlib/intern/filereader_zstd.c
new file mode 100644
index 00000000000..785a40cd1a1
--- /dev/null
+++ b/source/blender/blenlib/intern/filereader_zstd.c
@@ -0,0 +1,335 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2021 Blender Foundation
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup bli
+ */
+
+#include <string.h>
+#include <zstd.h>
+
+#include "BLI_blenlib.h"
+#include "BLI_endian_switch.h"
+#include "BLI_filereader.h"
+#include "BLI_math_base.h"
+
+#include "MEM_guardedalloc.h"
+
+typedef struct {
+  FileReader reader;
+
+  FileReader *base;
+
+  ZSTD_DCtx *ctx;
+  ZSTD_inBuffer in_buf;
+  size_t in_buf_max_size;
+
+  struct {
+    int num_frames;
+    size_t *compressed_ofs;
+    size_t *uncompressed_ofs;
+
+    char *cached_content;
+    int cached_frame;
+  } seek;
+} ZstdReader;
+
+static bool zstd_read_u32(FileReader *base, uint32_t *val)
+{
+  if (base->read(base, val, sizeof(uint32_t)) != sizeof(uint32_t)) {
+    return false;
+  }
+#ifdef __BIG_ENDIAN__
+  BLI_endian_switch_uint32(val);
+#endif
+  return true;
+}
+
+static bool zstd_read_seek_table(ZstdReader *zstd)
+{
+  FileReader *base = zstd->base;
+
+  /* The seek table frame is at the end of the file, so seek there
+   * and verify that there is enough data. */
+  if (base->seek(base, -4, SEEK_END) < 13) {
+    return false;
+  }
+  uint32_t magic;
+  if (!zstd_read_u32(base, &magic) || magic != 0x8F92EAB1) {
+    return false;
+  }
+
+  uint8_t flags;
+  if (base->seek(base, -5, SEEK_END) < 0 || base->read(base, &flags, 1) != 1) {
+    return false;
+  }
+  /* Bit 7 indicates checksums. Bits 5 and 6 must be zero. */
+  bool has_checksums = (flags & 0x80);
+  if (flags & 0x60) {
+    return false;
+  }
+
+  uint32_t num_frames;
+  if (base->seek(base, -9, SEEK_END) < 0 || !zstd_read_u32(base, &num_frames)) {
+    return false;
+  }
+
+  /* Each frame has either 2 or 3 uint32_t, and after that we have
+   * num_frames, flags and magic for another 9 bytes. */
+  uint32_t expected_frame_length = num_frames * (has_checksums ? 12 : 8) + 9;
+  /* The frame starts with another magic number and its length, but these
+   * two fields are not included when counting length. */
+  off64_t frame_start_ofs = 8 + expected_frame_length;
+  /* Sanity check: Before the start of the seek table frame,
+   * there must be num_frames frames, each of which at least 8 bytes long. */
+  off64_t seek_frame_start = base->seek(base, -frame_start_ofs, SEEK_END);
+  if (seek_frame_start < num_frames * 8) {
+    return false;
+  }
+
+  if (!zstd_read_u32(base, &magic) || magic != 0x184D2A5E) {
+    return false;
+  }
+
+  uint32_t frame_length;
+  if (!zstd_read_u32(base, &frame_length) || frame_length != expected_frame_length) {
+    return false;
+  }
+
+  zstd->seek.num_frames = num_frames;
+  zstd->seek.compressed_ofs = MEM_malloc_arrayN(num_frames + 1, sizeof(size_t), __func__);
+  zstd->seek.uncompressed_ofs = MEM_malloc_arrayN(num_frames + 1, sizeof(size_t), __func__);
+
+  size_t compressed_ofs = 0;
+  size_t uncompressed_ofs = 0;
+  for (int i = 0; i < num_frames; i++) {
+    uint32_t compressed_size, uncompressed_size;
+    if (!zstd_read_u32(base, &compressed_size) || !zstd_read_u32(base, &uncompressed_size)) {
+      break;
+    }
+    if (has_checksums && base->seek(base, 4, SEEK_CUR) < 0) {
+      break;
+    }
+    zstd->seek.compressed_ofs[i] = compressed_ofs;
+    zstd->seek.uncompressed_ofs[i] = uncompressed_ofs;
+    compressed_ofs += compressed_size;
+    uncompressed_ofs += uncompressed_size;
+  }
+  zstd->seek.compressed_ofs[num_frames] = compressed_ofs;
+  zstd->seek.uncompressed_ofs[num_frames] = uncompressed_ofs;
+
+  /* Seek to the end of the previous frame for the following BHead frame detection. */
+  if (seek_frame_start != compressed_ofs || base->seek(base, seek_frame_start, SEEK_SET) < 0) {
+    MEM_freeN(zstd->seek.compressed_ofs);
+    MEM_freeN(zstd->seek.uncompressed_ofs);
+    memset(&zstd->seek, 0, sizeof(zstd->seek));
+    return false;
+  }
+
+  zstd->seek.cached_frame = -1;
+
+  return true;
+}
+
+/* Find out which frame contains the given position in the uncompressed stream.
+ * Basically just bisection. */
+static int zstd_frame_from_pos(ZstdReader *zstd, size_t pos)
+{
+  int low = 0, high = zstd->seek.num_frames;
+
+  if (pos >= zstd->seek.uncompressed_ofs[zstd->seek.num_frames]) {
+    return -1;
+  }
+
+  while (low + 1 < high) {
+    int mid = low + ((high - low) >> 1);
+    if (zstd->seek.uncompressed_ofs[mid] <= pos) {
+      low = mid;
+    }
+    else {
+      high = mid;
+    }
+  }
+
+  return low;
+}
+
+/* Ensure that the currently loaded frame is the correct one. */
+static const char *zstd_ensure_cache(ZstdReader *zstd, int frame)
+{
+  if (zstd->seek.cached_frame == frame) {
+    /* Cached frame matches, so just return it. */
+    return zstd->seek.cached_content;
+  }
+
+  /* Cached frame doesn't match, so discard it and cache the wanted one onstead. */
+  MEM_SAFE_FREE(zstd->seek.cached_content);
+
+  size_t compressed_size = zstd->seek.compressed_ofs[frame + 1] - zstd->seek.compressed_ofs[frame];
+  size_t uncompressed_size = zstd->seek.uncompressed_ofs[frame + 1] -
+                             zstd->seek.uncompressed_ofs[frame];
+
+  char *uncompressed_data = MEM_mallocN(uncompressed_size, __func__);
+  char *compressed_data = MEM_mallocN(compressed_size, __func__);
+  if (zstd->base->seek(zstd->base, zstd->seek.compressed_ofs[frame], SEEK_SET) < 0 ||
+      zstd->base->read(zstd->base, compressed_data, compressed_size) < compressed_size) {
+    MEM_freeN(compressed_data);
+    MEM_freeN(uncompressed_data);
+    return NULL;
+  }
+
+  size_t res = ZSTD_decompressDCtx(
+      zstd->ctx, uncompressed_data, uncompressed_size, compressed_data, compressed_size);
+  MEM_freeN(compressed_data);
+  if (ZSTD_isError(res) || res < uncompressed_size) {
+    MEM_freeN(uncompressed_data);
+    return NULL;
+  }
+
+  zstd->seek.cached_frame = frame;
+  zstd->seek.cached_content = uncompressed_data;
+  return uncompressed_data;
+}
+
+static ssize_t zstd_read_seekable(FileReader *reader, void *buffer, size_t size)
+{
+  ZstdReader *zstd = (ZstdReader *)reader;
+
+  size_t end_offset = zstd->reader.offset + size, read_len = 0;
+  while (zstd->reader.offset < end_offset) {
+    int frame = zstd_frame_from_pos(zstd, zstd->reader.offset);
+    if (frame < 0) {
+      /* EOF is reached, so return as much as we can. */
+      break;
+    }
+
+    const char *framedata = zstd_ensure_cache(zstd, frame);
+    if (framedata == NULL) {
+      /* Error while reading the frame, so return as much as we can. */
+      break;
+    }
+
+    size_t frame_end_offset = min_zz(zstd->seek.uncompressed_ofs[frame + 1], end_offset);
+    size_t frame_read_len = frame_end_offset - zstd->reader.offset;
+
+    size_t offset_in_frame = zstd->reader.offset - zstd->seek.uncompressed_ofs[frame];
+    memcpy((char *)buffer + read_len, framedata + offset_in_frame, frame_read_len);
+    read_len += frame_read_len;
+    zstd->reader.offset = frame_end_offset;
+  }
+
+  return read_len;
+}
+
+static off64_t zstd_seek(FileReader *reader, off64_t offset, int whence)
+{
+  ZstdReader *zstd = (ZstdReader *)reader;
+  off64_t new_pos;
+  if (whence == SEEK_SET) {
+    new_pos = offset;
+  }
+  else if (whence == SEEK_END) {
+    new_pos = zstd->seek.uncompressed_ofs[zstd->seek.num_frames] + offset;
+  }
+  else {
+    new_pos = zstd->reader.offset + offset;
+  }
+
+  if (new_pos < 0 || new_pos > zstd->seek.uncompressed_ofs[zstd->seek.num_frames]) {
+    return -1;
+  }
+  zstd->reader.offset = new_pos;
+  return zstd->reader.offset;
+}
+
+static ssize_t zstd_read(FileReader *reader, void *buffer, size_t size)
+{
+  ZstdReader *zstd = (ZstdReader *)reader;
+  ZSTD_outBuffer output = {buffer, size, 0};
+
+  while (output.pos < output.size) {
+    if (zstd->in_buf.pos == zstd->in_buf.size) {
+      /* Ran out of buffered input data, read some more. */
+      zstd->in_buf.pos = 0;
+      ssize_t readsize = zstd->base->read(
+          zstd->base, (char *)zstd->in_buf.src, zstd->in_buf_max_size);
+
+      if (readsize > 0) {
+        /* We got some data, so mark the buffer as refilled. */
+        zstd->in_buf.size = readsize;
+      }
+      else {
+        /* The underlying file is EOF, so return as much as we can. */
+        break;
+      }
+    }
+
+    if (ZSTD_isError(ZSTD_decompressStream(zstd->ctx, &output, &zstd->in_buf))) {
+      break;
+    }
+  }
+
+  zstd->reader.offset += output.pos;
+  return output.pos;
+}
+
+static void zstd_close(FileReader *reader)
+{
+  ZstdReader *zstd = (ZstdReader *)reader;
+
+  ZSTD_freeDCtx(zstd->ctx);
+  if (zstd->reader.seek) {
+    MEM_freeN(zstd->seek.uncompressed_ofs);
+    MEM_freeN(zstd->seek.compressed_ofs);
+    MEM_freeN(zstd->seek.cached_content);
+  }
+  else {
+    MEM_freeN((void *)zstd->in_buf.src);
+  }
+
+  zstd->base->close(zstd->base);
+  MEM_freeN(zstd);
+}
+
+FileReader *BLI_filereader_new_zstd(FileReader *base)
+{
+  ZstdReader *zstd = MEM_callocN(sizeof(ZstdReader), __func__);
+
+  zstd->ctx = ZSTD_createDCtx();
+  zstd->base = base;
+
+  if (zstd_read_seek_table(zstd)) {
+    zstd->reader.read = zstd_read_seekable;
+    zstd->reader.seek = zstd_seek;
+  }
+  else {
+    zstd->reader.read = zstd_read;
+    zstd->reader.seek = NULL;
+
+    zstd->in_buf_max_size = ZSTD_DStreamInSize();
+    zstd->in_buf.src = MEM_mallocN(zstd->in_buf_max_size, "zstd in buf");
+    zstd->in_buf.size = zstd->in_buf_max_size;
+    /* This signals that the buffer has run out,
+     * which will make the read function refill it on the first call. */
+    zstd->in_buf.pos = zstd->in_buf_max_size;
+  }
+  zstd->reader.close = zstd_close;
+
+  return (FileReader *)zstd;
+}
diff --git a/source/blender/blenloader/CMakeLists.txt b/source/blender/blenloader/CMakeLists.txt
index f5baf0dcb83..89631588ed0 100644
--- a/source/blender/blenloader/CMakeLists.txt
+++ b/source/blender/blenloader/CMakeLists.txt
@@ -42,7 +42,7 @@ set(INC
 )
 
 set(INC_SYS
-  ${ZLIB_INCLUDE_DIRS}
+  ${ZSTD_INCLUDE_DIRS}
 )
 
 set(SRC
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 82fbb2083df..49c3497f996 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -1233,6 +1233,12 @@ static FileData *blo_filedata_from_file_descriptor(const char *filepath,
       rawfile = NULL; /* The Gzip FileReader takes ownership of `rawfile`. */
     }
   }
+  else if (BLI_file_magic_is_zstd(header)) {
+    file = BLI_filereader_new_zstd(rawfile);
+    if (file != NULL) {
+      rawfile = NULL; /* The Zstd FileReader takes ownership of `rawfile`. */
+    }
+  }
 
   /* Clean up `rawfile` if it wasn't taken over. */
   if (rawfile != NULL) {
@@ -1309,6 +1315,9 @@ FileData *blo_filedata_from_memory(const void *mem, int memsize, BlendFileReadRe
   if (BLI_file_magic_is_gzip(mem)) {
     file = BLI_filereader_new_gzip(mem_file);
   }
+  else if (BLI_file_magic_is_zstd(mem)) {
+    file = BLI_filereader_new_zstd(mem_file);
+  }
 
   if (file == NULL) {
     /* Compression initialization failed. */
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index 2ef4f630f15..90d58514eb5 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -78,7 +78,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <zlib.h>
 
 #ifdef WIN32
 #  include "BLI_winstuff.h"
@@ -134,14 +133,21 @@
 
 #include <errno.h>
 
+#include <zstd.h>
+
 /* Make preferences read-only. */
 #define U (*((const UserDef *)&U))
 
 /* ********* my write, buffered writing with minimum size chunks ************ */
 
 /* Use optimal allocation since blocks of this size are kept in memory for undo. */
-#define MYWRITE_BUFFER_SIZE (MEM_SIZE_OPTIMAL(1 << 17)) /* 128kb */
-#define MYWRITE_MAX_CHUNK (MEM_SIZE_OPTIMAL(1 << 15))   /* ~32kb */
+#define MEM_BUFFER_SIZE (MEM_SIZE_OPTIMAL(1 << 17)) /* 128kb */
+#define MEM_CHUNK_SIZE (MEM_SIZE_OPTIMAL(1 << 15))  /* ~32kb */
+
+#define ZSTD_BUFFER_SIZE (1 << 21) /* 2mb */
+#define ZSTD_CHUNK_SIZE (1 << 20)  /* 1mb */
+
+#define ZSTD_COMPRESSION_LEVEL 3
 
 /** Use if we want to store how many bytes have been written to the file. */
 // #define USE_WRITE_DATA_LEN
@@ -152,9 +158,16 @@
 
 typedef enum {
   WW_WRAP_NONE = 1,
-  WW_WRAP_ZLIB,
+  WW_WRAP_ZSTD,
 } eWriteWrapType;
 
+typedef struct ZstdFrame {
+  struct ZstdFrame *next, *prev;
+
+  uint32_t compressed_size;
+  uint32_t uncompressed_size;
+} ZstdFrame;
+
 typedef struct WriteWrap WriteWrap;
 struct WriteWrap {
   /* callbacks */
@@ -166,15 +179,23 @@ struct WriteWrap {
   bool use_buf;
 
   /* internal */
-  union {
-    int file_handle;
-    gzFile gz_handle;
-  } _user_data;
+  int file_handle;
+  struct {
+    ListBase threadpool;
+    ListBase tasks;
+    ThreadMutex mutex;
+    ThreadCondition condition;
+    int next_frame;
+    int num_frames;
+
+    int level;
+    ListBase frames;
+
+    bool write_error;
+  } zstd;
 };
 
 /* none */
-#define FILE_HANDLE(ww) (ww)->_user_data.file_handle
-
 static bool ww_open_none(WriteWrap *ww, const char *filepath)
 {
   int file;
@@ -182,7 +203,7 @@ static bool ww_open_none(WriteWrap *ww, const char *filepath)
   file = BLI_open(filepath, O_BINARY + O_WRONLY + O_CREAT + O_TRUNC, 0666);
 
   if (file != -1) {
-    FILE_HANDLE(ww) = file;
+    ww->file_handle = file;
     return true;
   }
 
@@ -190,39 +211,170 @@ static bool ww_open_none(WriteWrap *ww, const char *filepath)
 }
 static bool ww_close_none(WriteWrap *ww)
 {
-  return (close(FILE_HANDLE(ww)) != -1);
+  return (close(ww->file_handle) != -1);
 }
 static size_t ww_write_none(WriteWrap *ww, const char *buf, size_t buf_len)
 {
-  return write(FILE_HANDLE(ww), buf, buf_len);
+  return write(ww->file_handle, buf, buf_len);
 }
-#undef FILE_HANDLE
 
-/* zlib */
-#define FILE_HANDLE(ww) (ww)->_user_data.gz_handle
+/* zstd */
+
+typedef struct {
+  struct ZstdWriteBlockTask *next, *prev;
+  void *data;
+  size_t size;
+  int frame_number;
+  WriteWrap *ww;
+} ZstdWriteBlockTask;
 
-static bool ww_open_zlib(WriteWrap *ww, const char *filepath)
+static void *zstd_write_task(void *userdata)
 {
-  gzFile file;
+  ZstdWriteBlockTask *task = userdata;
+  WriteWrap *ww = task->ww;
 
-  file = BLI_gzopen(filepath, "wb1");
+  size_t out_buf_len = ZSTD_compressBound(task->size);
+  void *out_buf = MEM_mallocN(out_buf_len, "Zstd out buffer");
+  size_t out_size = ZSTD_compress(
+      out_buf, out_buf_len, task->data, task->size, ZSTD_COMPRESSION_LEVEL);
 
-  if (file != Z_NULL) {
-    FILE_HANDLE(ww) = file;
-    return true;
+  MEM_freeN(task->data);
+
+  BLI_mutex_lock(&ww->zstd.mutex);
+
+  while (ww->zstd.next_frame != task->frame_number) {
+    BLI_condition_wait(&ww->zstd.condition, &ww->zstd.mutex);
   }
 
-  return false;
+  if (ZSTD_isError(out_size)) {
+    ww->zstd.write_error = true;
+  }
+  else {
+    if (ww_write_none(ww, out_buf, out_size) == out_size) {
+      ZstdFrame *frameinfo = MEM_mallocN(sizeof(ZstdFrame), "zstd frameinfo");
+      frameinfo->uncompressed_size = task->size;
+      frameinfo->compressed_size = out_size;
+      BLI_addtail(&ww->zstd.frames, frameinfo);
+    }
+    else {
+      ww->zstd.write_error = true;
+    }
+  }
+
+  ww->zstd.next_frame++;
+
+  BLI_mutex_unlock(&ww->zstd.mutex);
+  BLI_condition_notify_all(&ww->zstd.condition);
+
+  MEM_freeN(out_buf);
+  return NULL;
+}
+
+static bool ww_open_zstd(WriteWrap *ww, const char *filepath)
+{
+  if (!ww_open_none(ww, filepath)) {
+    return false;
+  }
+
+  /* Leave one thread open for the main writing logic, unless we only have one HW thread. */
+  int num_threads = max_ii(1, BLI_system_thread_count() - 1);
+  BLI_threadpool_init(&ww->zstd.threadpool, zstd_write_task, num_threads);
+  BLI_mutex_init(&ww->zstd.mutex);
+  BLI_condition_init(&ww->zstd.condition);
+
+  return true;
 }
-static bool ww_close_zlib(WriteWrap *ww)
+
+static void zstd_write_u32_le(WriteWrap *ww, uint32_t val)
+{
+#ifdef __BIG_ENDIAN__
+  BLI_endian_switch_uint32(&val);
+#endif
+  ww_write_none(ww, (char *)&val, sizeof(uint32_t));
+}
+
+/* In order to implement efficient seeking when reading the .blend, we append
+ * a skippable frame that encodes information about the other frames present
+ * in the file.
+ * The format here follows the upstream spec for seekable files:
+ * https://github.com/facebook/zstd/blob/master/contrib/seekable_format/zstd_seekable_compression_format.md
+ * If this information is not present in a file (e.g. if it was compressed
+ * with external tools), it can still be opened in Blender, but seeking will
+ * not be supported, so more memory might be needed. */
+static void zstd_write_seekable_frames(WriteWrap *ww)
+{
+  /* Write seek table header (magic number and frame size). */
+  zstd_write_u32_le(ww, 0x184D2A5E);
+
+  /* The actual frame number might not match ww->zstd.num_frames if there was a write error. */
+  const uint32_t num_frames = BLI_listbase_count(&ww->zstd.frames);
+  /* Each frame consists of two u32, so 8 bytes each.
+   * After the frames, a footer containing two u32 and one byte (9 bytes total) is written. */
+  const uint32_t frame_size = num_frames * 8 + 9;
+  zstd_write_u32_le(ww, frame_size);
+
+  /* Write seek table entries. */
+  LISTBASE_FOREACH (ZstdFrame *, frame, &ww->zstd.frames) {
+    zstd_write_u32_le(ww, frame->compressed_size);
+    zstd_write_u32_le(ww, frame->uncompressed_size);
+  }
+
+  /* Write seek table footer (number of frames, option flags and second magic number). */
+  zstd_write_u32_le(ww, num_frames);
+  const char flags = 0; /* We don't store checksums for each frame. */
+  ww_write_none(ww, &flags, 1);
+  zstd_write_u32_le(ww, 0x8F92EAB1);
+}
+
+static bool ww_close_zstd(WriteWrap *ww)
 {
-  return (gzclose(FILE_HANDLE(ww)) == Z_OK);
+  BLI_threadpool_end(&ww->zstd.threadpool);
+  BLI_freelistN(&ww->zstd.tasks);
+
+  BLI_mutex_end(&ww->zstd.mutex);
+  BLI_condition_end(&ww->zstd.condition);
+
+  zstd_write_seekable_frames(ww);
+  BLI_freelistN(&ww->zstd.frames);
+
+  return ww_close_none(ww) && !ww->zstd.write_error;
 }
-static size_t ww_write_zlib(WriteWrap *ww, const char *buf, size_t buf_len)
+
+static size_t ww_write_zstd(WriteWrap *ww, const char *buf, size_t buf_len)
 {
-  return gzwrite(FILE_HANDLE(ww), buf, buf_len);
+  if (ww->zstd.write_error) {
+    return 0;
+  }
+
+  ZstdWriteBlockTask *task = MEM_mallocN(sizeof(ZstdWriteBlockTask), __func__);
+  task->data = MEM_mallocN(buf_len, __func__);
+  memcpy(task->data, buf, buf_len);
+  task->size = buf_len;
+  task->frame_number = ww->zstd.num_frames++;
+  task->ww = ww;
+
+  BLI_mutex_lock(&ww->zstd.mutex);
+  BLI_addtail(&ww->zstd.tasks, task);
+
+  /* If there's a free worker thread, just push the block into that thread.
+   * Otherwise, we wait for the earliest thread to finish.
+   * We look up the earliest thread while holding the mutex, but release it
+   * before joining the thread to prevent a deadlock. */
+  ZstdWriteBlockTask *first_task = ww->zstd.tasks.first;
+  BLI_mutex_unlock(&ww->zstd.mutex);
+  if (!BLI_available_threads(&ww->zstd.threadpool)) {
+    BLI_threadpool_remove(&ww->zstd.threadpool, first_task);
+
+    /* If the task list was empty before we pushed our task, there should
+     * always be a free thread. */
+    BLI_assert(first_task != task);
+    BLI_remlink(&ww->zstd.tasks, first_task);
+    MEM_freeN(first_task);
+  }
+  BLI_threadpool_insert(&ww->zstd.threadpool, task);
+
+  return buf_len;
 }
-#undef FILE_HANDLE
 
 /* --- end compression types --- */
 
@@ -231,11 +383,11 @@ static void ww_handle_init(eWriteWrapType ww_type, WriteWrap *r_ww)
   memset(r_ww, 0, sizeof(*r_ww));
 
   switch (ww_type) {
-    case WW_WRAP_ZLIB: {
-      r_ww->open = ww_open_zlib;
-      r_ww->close = ww_close_zlib;
-      r_ww->write = ww_write_zlib;
-      r_ww->use_buf = false;
+    case WW_WRAP_ZSTD: {
+      r_ww->open = ww_open_zstd;
+      r_ww->close = ww_close_zstd;
+      r_ww->write = ww_write_zstd;
+      r_ww->use_buf = true;
       break;
     }
     default: {
@@ -257,10 +409,17 @@ static void ww_handle_init(eWriteWrapType ww_type, WriteWrap *r_ww)
 typedef struct {
   const struct SDNA *sdna;
 
-  /** Use for file and memory writing (fixed size of #MYWRITE_BUFFER_SIZE). */
-  uchar *buf;
-  /** Number of bytes used in #WriteData.buf (flushed when exceeded). */
-  size_t buf_used_len;
+  struct {
+    /** Use for file and memory writing (size stored in max_size). */
+    uchar *buf;
+    /** Number of bytes used in #WriteData.buf (flushed when exceeded). */
+    size_t used_len;
+
+    /** Maximum size of the buffer. */
+    size_t max_size;
+    /** Threshold above which writes get their own chunk. */
+    size_t chunk_size;
+  } buffer;
 
 #ifdef USE_WRITE_DATA_LEN
   /** Total number of bytes written. */
@@ -276,7 +435,7 @@ typedef struct {
   bool use_memfile;
 
   /**
-   * Wrap writing, so we can use zlib or
+   * Wrap writing, so we can use zstd or
    * other compression types later, see: G_FILE_COMPRESS
    * Will be NULL for UNDO.
    */
@@ -296,7 +455,15 @@ static WriteData *writedata_new(WriteWrap *ww)
   wd->ww = ww;
 
   if ((ww == NULL) || (ww->use_buf)) {
-    wd->buf = MEM_mallocN(MYWRITE_BUFFER_SIZE, "wd->buf");
+    if (ww == NULL) {
+      wd->buffer.max_size = MEM_BUFFER_SIZE;
+      wd->buffer.chunk_size = MEM_CHUNK_SIZE;
+    }
+    else {
+      wd->buffer.max_size = ZSTD_BUFFER_SIZE;
+      wd->buffer.chunk_size = ZSTD_CHUNK_SIZE;
+    }
+    wd->buffer.buf = MEM_mallocN(wd->buffer.max_size, "wd->buffer.buf");
   }
 
   return wd;
@@ -330,8 +497,8 @@ static void writedata_do_write(WriteData *wd, const void *mem, size_t memlen)
 
 static void writedata_free(WriteData *wd)
 {
-  if (wd->buf) {
-    MEM_freeN(wd->buf);
+  if (wd->buffer.buf) {
+    MEM_freeN(wd->buffer.buf);
   }
   MEM_freeN(wd);
 }
@@ -348,9 +515,9 @@ static void writedata_free(WriteData *wd)
  */
 static void mywrite_flush(WriteData *wd)
 {
-  if (wd->buf_used_len != 0) {
-    writedata_do_write(wd, wd->buf, wd->buf_used_len);
-    wd->buf_used_len = 0;
+  if (wd->buffer.used_len != 0) {
+    writedata_do_write(wd, wd->buffer.buf, wd->buffer.used_len);
+    wd->buffer.used_len = 0;
   }
 }
 
@@ -374,20 +541,20 @@ static void mywrite(WriteData *wd, const void *adr, size_t len)
   wd->write_len += len;
 #endif
 
-  if (wd->buf == NULL) {
+  if (wd->buffer.buf == NULL) {
     writedata_do_write(wd, adr, len);
   }
   else {
     /* if we have a single big chunk, write existing data in
      * buffer and write out big chunk in smaller pieces */
-    if (len > MYWRITE_MAX_CHUNK) {
-      if (wd->buf_used_len != 0) {
-        writedata_do_write(wd, wd->buf, wd->buf_used_len);
-        wd->buf_used_len = 0;
+    if (len > wd->buffer.chunk_size) {
+      if (wd->buffer.used_len != 0) {
+        writedata_do_write(wd, wd->buffer.buf, wd->buffer.used_len);
+        wd->buffer.used_len = 0;
       }
 
       do {
-        size_t writelen = MIN2(len, MYWRITE_MAX_CHUNK);
+        size_t writelen = MIN2(len, wd->buffer.chunk_size);
         writedata_do_write(wd, adr, writelen);
         adr = (const char *)adr + writelen;
         len -= writelen;
@@ -397,14 +564,14 @@ static void mywrite(WriteData *wd, const void *adr, size_t len)
     }
 
     /* if data would overflow buffer, write out the buffer */
-    if (len + wd->buf_used_len > MYWRITE_BUFFER_SIZE - 1) {
-      writedata_do_write(wd, wd->buf, wd->buf_used_len);
-      wd->buf_used_len = 0;
+    if (len + wd->buffer.used_len > wd->buffer.max_size - 1) {
+      writedata_do_write(wd, wd->buffer.buf, wd->buffer.used_len);
+      wd->buffer.used_len = 0;
     }
 
     /* append data at end of buffer */
-    memcpy(&wd->buf[wd->buf_used_len], adr, len);
-    wd->buf_used_len += len;
+    memcpy(&wd->buffer.buf[wd->buffer.used_len], adr, len);
+    wd->buffer.used_len += len;
   }
 }
 
@@ -435,9 +602,9 @@ static WriteData *mywrite_begin(WriteWrap *ww, MemFile *compare, MemFile *curren
  */
 static bool mywrite_end(WriteData *wd)
 {
-  if (wd->buf_used_len != 0) {
-    writedata_do_write(wd, wd->buf, wd->buf_used_len);
-    wd->buf_used_len = 0;
+  if (wd->buffer.used_len != 0) {
+    writedata_do_write(wd, wd->buffer.buf, wd->buffer.used_len);
+    wd->buffer.used_len = 0;
   }
 
   if (wd->use_memfile) {
@@ -1155,7 +1322,6 @@ bool BLO_write_file(Main *mainvar,
                     ReportList *reports)
 {
   char tempname[FILE_MAX + 1];
-  eWriteWrapType ww_type;
   WriteWrap ww;
 
   eBLO_WritePathRemap remap_mode = params->remap_mode;
@@ -1177,14 +1343,7 @@ bool BLO_write_file(Main *mainvar,
   /* open temporary file, so we preserve the original in case we crash */
   BLI_snprintf(tempname, sizeof(tempname), "%s@", filepath);
 
-  if (write_flags & G_FILE_COMPRESS) {
-    ww_type = WW_WRAP_ZLIB;
-  }
-  else {
-    ww_type = WW_WRAP_NONE;
-  }
-
-  ww_handle_init(ww_type, &ww);
+  ww_handle_init((write_flags & G_FILE_COMPRESS) ? WW_WRAP_ZSTD : WW_WRAP_NONE, &ww);
 
   if (ww.open(&ww, tempname) == false) {
     BKE_reportf(
diff --git a/source/blender/windowmanager/CMakeLists.txt b/source/blender/windowmanager/CMakeLists.txt
index b7fbb9bb82b..4d65726fe2b 100644
--- a/source/blender/windowmanager/CMakeLists.txt
+++ b/source/blender/windowmanager/CMakeLists.txt
@@ -48,10 +48,6 @@ set(INC
   ${CMAKE_BINARY_DIR}/source/blender/makesdna/intern
 )
 
-set(INC_SYS
-  ${ZLIB_INCLUDE_DIRS}
-)
-
 set(SRC
   intern/wm.c
   intern/wm_cursors.c
diff --git a/source/blender/windowmanager/intern/wm_files.c b/source/blender/windowmanager/intern/wm_files.c
index c3789abf2dd..f83511e76f0 100644
--- a/source/blender/windowmanager/intern/wm_files.c
+++ b/source/blender/windowmanager/intern/wm_files.c
@@ -516,8 +516,13 @@ static int wm_read_exotic(const char *name)
   /* check for compressed .blend */
   FileReader *compressed_file = NULL;
   if (BLI_file_magic_is_gzip(header)) {
+    /* In earlier versions of Blender (before 3.0), compressed files used Gzip instead of Zstd.
+     * While these files will no longer be written, there still needs to be reading support. */
     compressed_file = BLI_filereader_new_gzip(rawfile);
   }
+  else if (BLI_file_magic_is_zstd(header)) {
+    compressed_file = BLI_filereader_new_zstd(rawfile);
+  }
 
   /* If a compression signature matches, try decompressing the start and check if it's a .blend */
   if (compressed_file != NULL) {