[shell] Print command result in Zephyr platform

1. Add streamer_print_result() function for printing either:
   - "Done" or
   - "Error: <error_string_or_code>"
   after each shell command and use that in the default
   and Zephyr shell implementation. Before that Zephyr would
   not print the result at all (unlike other platforms).
2. Lock Matter stack before running a shell command on
   Zephyr platform.

Signed-off-by: Damian Krolik <[email protected]>

src/lib/shell/MainLoopDefault.cpp

@@ -163,22 +163,8 @@ void ProcessShellLine(intptr_t args)
 
     if (argc > 0)
     {
-        CHIP_ERROR retval = Engine::Root().ExecCommand(argc, argv);
-
-        if (retval != CHIP_NO_ERROR)
-        {
-            char errorStr[160];
-            bool errorStrFound = FormatCHIPError(errorStr, sizeof(errorStr), retval);
-            if (!errorStrFound)
-            {
-                errorStr[0] = 0;
-            }
-            streamer_printf(streamer_get(), "Error %s: %s\r\n", argv[0], errorStr);
-        }
-        else
-        {
-            streamer_printf(streamer_get(), "Done\r\n", argv[0]);
-        }
+        CHIP_ERROR error = Engine::Root().ExecCommand(argc, argv);
+        streamer_print_result(streamer_get(), error);
     }
     MemoryFree(line);
     streamer_printf(streamer_get(), CHIP_SHELL_PROMPT);

src/lib/shell/MainLoopZephyr.cpp

@@ -20,13 +20,22 @@
 #include <lib/core/CHIPError.h>
 #include <lib/shell/Engine.h>
 #include <lib/shell/streamer_zephyr.h>
+#include <platform/CHIPDeviceLayer.h>
 
 using chip::Shell::Engine;
 
 static int cmd_matter(const struct shell * shell, size_t argc, char ** argv)
 {
-    chip::Shell::streamer_set_shell(shell);
-    return (Engine::Root().ExecCommand(argc - 1, argv + 1) == CHIP_NO_ERROR) ? 0 : -ENOEXEC;
+    CHIP_ERROR error;
+
+    {
+        chip::DeviceLayer::StackLock lock;
+        chip::Shell::streamer_set_shell(shell);
+        error = Engine::Root().ExecCommand(argc - 1, argv + 1);
+        chip::Shell::streamer_print_result(chip::Shell::streamer_get(), error);
+    }
+
+    return error == CHIP_NO_ERROR ? 0 : -ENOEXEC;
 }
 
 static int RegisterCommands()

src/lib/shell/streamer.cpp

@@ -23,6 +23,7 @@
 
 #include "streamer.h"
 
+#include <lib/support/CodeUtils.h>
 #include <lib/support/EnforceFormat.h>
 #include <lib/support/logging/Constants.h>
 #include <limits.h>
@@ -87,5 +88,17 @@ void streamer_print_hex(streamer_t * self, const uint8_t * bytes, int len)
     }
 }
 
+void streamer_print_result(streamer_t * self, CHIP_ERROR error)
+{
+    if (error != CHIP_NO_ERROR)
+    {
+        streamer_printf(self, "Error: %" CHIP_ERROR_FORMAT "\r\n", error.Format());
+    }
+    else
+    {
+        streamer_printf(self, "Done\r\n");
+    }
+}
+
 } // namespace Shell
 } // namespace chip

src/lib/shell/streamer.h

@@ -23,6 +23,8 @@
 
 #pragma once
 
+#include <lib/core/CHIPError.h>
+
 #include <stdarg.h>
 #include <stddef.h>
 #include <stdint.h>
@@ -51,6 +53,7 @@ ssize_t streamer_write(streamer_t * self, const char * buf, size_t len);
 ssize_t streamer_vprintf(streamer_t * self, const char * fmt, va_list ap);
 ssize_t streamer_printf(streamer_t * self, const char * fmt, ...);
 void streamer_print_hex(streamer_t * self, const uint8_t * data, int len);
+void streamer_print_result(streamer_t * self, CHIP_ERROR error);
 streamer_t * streamer_get();
 
 } // namespace Shell