Add zlib compress (which is surprisingly fast)

.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

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

src/algo-heatshrink.c

@@ -71,4 +71,4 @@ void heatshrink_uncompress(uint8_t *input, size_t insize, uint8_t *output, size_
     }
 
     *outsize = polled;
-}
+}

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);
+}

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__

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);