From 4def68f4c077d333ae0752a122b2560f118116cc Mon Sep 17 00:00:00 2001
From: Jonathan Phippen <jophippe@microsoft.com>
Date: Wed, 17 Jul 2024 15:09:39 -0700
Subject: [PATCH] Added valgrind to container and updated sample and README to
 show example of checking for memory leaks

---
 NativeBlink/.devcontainer/Dockerfile |  2 +-
 NativeBlink/CMakeLists.txt           |  8 ++++++--
 NativeBlink/CMakePresets.json        |  8 ++++++++
 NativeBlink/README.md                | 26 ++++++++++++++++++++++++++
 NativeBlink/main.c                   |  6 ++++++
 5 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/NativeBlink/.devcontainer/Dockerfile b/NativeBlink/.devcontainer/Dockerfile
index 706f8ff..e7e10c8 100644
--- a/NativeBlink/.devcontainer/Dockerfile
+++ b/NativeBlink/.devcontainer/Dockerfile
@@ -1,6 +1,6 @@
 FROM mcr.microsoft.com/azurespheresdk:latest
 
 RUN apt update && \
-    apt install -y libncurses5 gdb && \
+    apt install -y libncurses5 gdb valgrind && \
     apt autoremove -y && \
     apt clean -y
diff --git a/NativeBlink/CMakeLists.txt b/NativeBlink/CMakeLists.txt
index 3c6c0e3..6254566 100644
--- a/NativeBlink/CMakeLists.txt
+++ b/NativeBlink/CMakeLists.txt
@@ -6,12 +6,16 @@ cmake_minimum_required(VERSION 3.20)
 project(HelloWorld_HighLevelApp C)
 include(CTest)
 
-azsphere_configure_tools(TOOLS_REVISION "23.05")
-azsphere_configure_api(TARGET_API_SET "16")
+azsphere_configure_tools(TOOLS_REVISION "24.03")
+azsphere_configure_api(TARGET_API_SET "17")
 
 add_executable(${PROJECT_NAME} main.c led.c)
 target_link_libraries(${PROJECT_NAME} applibs gcc_s c)
 
+if(LEAK)
+    target_compile_definitions(${PROJECT_NAME} PUBLIC LEAK)
+endif()
+
 # TARGET_HARDWARE and TARGET_DEFINITION relate to the hardware definition targeted by this sample.
 # When using this sample with other hardware, replace TARGET_HARDWARE with the name of that hardware.
 # For example, to target the Avnet MT3620 Starter Kit, use the value "avnet_mt3620_sk".
diff --git a/NativeBlink/CMakePresets.json b/NativeBlink/CMakePresets.json
index 2bd5b5f..dbdf6cb 100644
--- a/NativeBlink/CMakePresets.json
+++ b/NativeBlink/CMakePresets.json
@@ -52,6 +52,14 @@
       "cacheVariables": {
         "CMAKE_BUILD_TYPE": "Release"
       }
+    },
+    {
+      "name": "x86-Debug-Leak",
+      "displayName": "x86-Debug-Leak",
+      "inherits": "x86-Debug",
+      "cacheVariables": {
+        "LEAK": true
+      }
     }
   ],
   "buildPresets": [
diff --git a/NativeBlink/README.md b/NativeBlink/README.md
index 68b4bb8..698e5e1 100644
--- a/NativeBlink/README.md
+++ b/NativeBlink/README.md
@@ -83,6 +83,32 @@ When debugging, open the Terminal Window (Ctrl + `) to see program output, which
 
     ![Screenshot that shows how to run the CTests.](.media/run_ctests.png)
 
+### Check for memory leaks
+
+1. Use the Toolbar to select the configure preset "x86-Debug-Leak", and wait for CMake to finish generating the cache.
+
+    (Alternatively, open the Command Palette, run the command "CMake: Select Configure Preset", select the "x86-Debug-Leak" Preset.)
+
+2. Use the Toolbar to build.
+
+    (Alternatively, open the Command Palette and run the command "CMake: Build" to build.)
+
+3. Open the Terminal Window (Ctrl + `) and run the following command to start running Valgrind on the app:
+```
+valgrind --leak-check=full --show-leak-kinds=definite out/x86-Debug-Leak/HelloWorld_HighLevelApp
+```
+
+4. After the app runs for a while, stop the app (Ctrl + C) and observe the output from Valgrind. Note that Valgrind correctly identifies memory that is definitely lost in main():
+```
+HEAP SUMMARY:
+    in use at exit: 146,511 bytes in 7 blocks
+  total heap usage: 7 allocs, 0 frees, 146,511 bytes allocated
+
+8 bytes in 2 blocks are definitely lost in loss record 2 of 6
+   at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
+   by 0x10931F: main (main.c:66)
+```
+
 ## Project expectations
 
 ### Expected support for the code
diff --git a/NativeBlink/main.c b/NativeBlink/main.c
index 2d08f2f..0e62496 100644
--- a/NativeBlink/main.c
+++ b/NativeBlink/main.c
@@ -9,6 +9,7 @@
 // - gpio (digital input for button)
 // - log (displays messages in the Device Output window during debugging)
 
+#include <stdlib.h>
 #include <stdbool.h>
 #include <errno.h>
 #include <string.h>
@@ -60,5 +61,10 @@ int main(void)
         nanosleep(&sleepTime, NULL);
         LED_Off(fd);
         nanosleep(&sleepTime, NULL);
+#ifdef LEAK
+        // Intentionally leak here to show an example of using valgrind to detect memory leaks
+        int* leak = (int*)malloc(sizeof(int));
+        *leak = 1;
+#endif
     }
 }
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