From ffdb902b029226c448f1287eb84f11c354e9957e Mon Sep 17 00:00:00 2001
From: Jannis Achstetter <kripton@kripserver.net>
Date: Tue, 8 Jun 2021 21:17:30 +0200
Subject: [PATCH] Add zlib compress (which is surprisingly fast)

---
 .gitmodules           |  9 +++++++++
 lib/snappy            |  1 +
 lib/zlib              |  1 +
 lib/zstd              |  1 +
 src/CMakeLists.txt    |  9 +++++++++
 src/algo-heatshrink.c |  2 +-
 src/algo-zlib.c       | 20 ++++++++++++++++++++
 src/algo-zlib.h       | 10 ++++++++++
 src/main.c            |  9 +++++++++
 9 files changed, 61 insertions(+), 1 deletion(-)
 create mode 160000 lib/snappy
 create mode 160000 lib/zlib
 create mode 160000 lib/zstd
 create mode 100644 src/algo-zlib.c
 create mode 100644 src/algo-zlib.h

diff --git a/.gitmodules b/.gitmodules
index 4fb59e2..d04a4a3 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,12 @@
 [submodule "lib/heatshrink"]
 	path = lib/heatshrink
 	url = https://github.com/kripton/heatshrink.git
+[submodule "lib/snappy"]
+	path = lib/snappy
+	url = https://github.com/kripton/snappy.git
+[submodule "lib/zstd"]
+	path = lib/zstd
+	url = https://github.com/kripton/zstd.git
+[submodule "lib/zlib"]
+	path = lib/zlib
+	url = https://github.com/kripton/zlib.git
diff --git a/lib/snappy b/lib/snappy
new file mode 160000
index 0000000..b638ebe
--- /dev/null
+++ b/lib/snappy
@@ -0,0 +1 @@
+Subproject commit b638ebe5d95ec4559921a72f8c2bbc4b1b5a2fd0
diff --git a/lib/zlib b/lib/zlib
new file mode 160000
index 0000000..4773d80
--- /dev/null
+++ b/lib/zlib
@@ -0,0 +1 @@
+Subproject commit 4773d8033b53126cf4bf48bebc41338c90a78332
diff --git a/lib/zstd b/lib/zstd
new file mode 160000
index 0000000..8a3bdfa
--- /dev/null
+++ b/lib/zstd
@@ -0,0 +1 @@
+Subproject commit 8a3bdfaa7bb2944dbed1ce9dede39f512d6da3f9
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f5a54b4..91834a7 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -12,12 +12,14 @@ pico_sdk_init()
 
 ## Include the CMakeLists-files of (non-pico-sdk)-libraries we will be using
 include(../lib/heatshrink/CMakeLists.txt)
+include(../lib/zlib/interfaceLibForPicoSDK.cmake)
 
 ## Add our own C/C++ files here
 ## Sorted alphabetically
 add_executable(${CMAKE_PROJECT_NAME}
     ${TINYUSB_LIBNETWORKING_SOURCES}
     algo-heatshrink.c
+    algo-zlib.c
     main.c
 )
 
@@ -29,6 +31,12 @@ target_compile_definitions(${CMAKE_PROJECT_NAME}
     PUBLIC HEATSHRINK_STATIC_LOOKAHEAD_BITS=6
 )
 
+## Config for the zlib library to reduce memory usage
+target_compile_definitions(${CMAKE_PROJECT_NAME}
+    PUBLIC MAX_WBITS=9
+    PUBLIC MAX_MEM_LEVEL=4
+)
+
 ## Needed so tusb_config.h is found by the tinyUSB-library included in the pico-sdk
 target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
     ${CMAKE_CURRENT_LIST_DIR}
@@ -39,6 +47,7 @@ target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
 target_link_libraries(${CMAKE_PROJECT_NAME}
     heatshrink
     pico_stdlib
+    zlib
 )
 
 ## enable usb output, disable uart output
diff --git a/src/algo-heatshrink.c b/src/algo-heatshrink.c
index aacf3f5..d2381ea 100644
--- a/src/algo-heatshrink.c
+++ b/src/algo-heatshrink.c
@@ -71,4 +71,4 @@ void heatshrink_uncompress(uint8_t *input, size_t insize, uint8_t *output, size_
     }
 
     *outsize = polled;
-}
\ No newline at end of file
+}
diff --git a/src/algo-zlib.c b/src/algo-zlib.c
new file mode 100644
index 0000000..6aa223d
--- /dev/null
+++ b/src/algo-zlib.c
@@ -0,0 +1,20 @@
+#include "algo-zlib.h"
+
+#include "../lib/zlib/zlib.h"
+
+void zlib_init()
+{
+}
+
+void zlib_compress(uint8_t *input, size_t insize, uint8_t *output, size_t *outsize)
+{
+    long unsigned int outsize2 = *outsize;
+    compress2(output, &outsize2, input, insize, 4);
+    *outsize = outsize2;
+}
+
+void zlib_uncompress(uint8_t *input, size_t insize, uint8_t *output, size_t *outsize)
+{
+    long unsigned int outsize2 = *outsize;
+    uncompress(output, &outsize2, input, insize);
+}
diff --git a/src/algo-zlib.h b/src/algo-zlib.h
new file mode 100644
index 0000000..c1618b8
--- /dev/null
+++ b/src/algo-zlib.h
@@ -0,0 +1,10 @@
+#ifndef __ALGO_ZLIB_H__
+#define __ALGO_ZLIB_H__
+
+#include "pico/stdlib.h"
+
+void zlib_init();
+void zlib_compress(uint8_t* input, size_t insize, uint8_t* output, size_t* outsize);
+void zlib_uncompress(uint8_t* input, size_t insize, uint8_t* output, size_t* outsize);
+
+#endif // __ALGO_ZLIB_H__
diff --git a/src/main.c b/src/main.c
index cee8dd1..717023f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -16,6 +16,7 @@
 #include "picotool_binary_information.h"
 
 #include "algo-heatshrink.h"
+#include "algo-zlib.h"
 
 
 // TEST VECTORS
@@ -50,6 +51,7 @@ struct algo {
 
 enum {
     ALGO_HEATSHRINK,
+    ALGO_ZLIB,
     // Add more HERE
     ALGO_NUM_TOTAL
 };
@@ -180,6 +182,13 @@ int main() {
     algos[ALGO_HEATSHRINK].uncompress = heatshrink_uncompress;
     algos[ALGO_HEATSHRINK].init();
 
+    // Algo 0: zlib
+    sprintf(algos[ALGO_ZLIB].name, "ZLIB");
+    algos[ALGO_ZLIB].init = zlib_init;
+    algos[ALGO_ZLIB].compress = zlib_compress;
+    algos[ALGO_ZLIB].uncompress = zlib_uncompress;
+    algos[ALGO_ZLIB].init();
+
     finish_time = time_us_32();
     elapsed_time = finish_time - start_time;
     printf("%luµs\n", elapsed_time);