libc: Add shell support

This is useful as a placeholder for all commands common to applications.
For now we start with malloc stats, useful in debugging HEAP issues.

Signed-off-by: Chaitanya Tata <[email protected]>

Author: krish2718

doc/releases/release-notes-3.5.rst

@@ -232,6 +232,58 @@ Devicetree
 Libraries / Subsystems
 **********************
 
+* Management
+
+  * Introduced MCUmgr client support with handlers for img_mgmt and os_mgmt.
+
+  * Added response checking to MCUmgr's :c:enumerator:`MGMT_EVT_OP_CMD_RECV`
+    notification callback to allow applications to reject MCUmgr commands.
+
+  * MCUmgr SMP version 2 error translation (to legacy MCUmgr error code) is now
+    supported in function handlers by setting ``mg_translate_error`` of
+    :c:struct:`mgmt_group` when registering a transport. See
+    :c:type:`smp_translate_error_fn` for function details.
+* shell
+
+  * Added an application shell module with helpers common to all applications.
+
+  * Fixed an issue with MCUmgr img_mgmt group whereby the size of the upload in
+    the initial packet was not checked.
+
+  * Fixed an issue with MCUmgr fs_mgmt group whereby some status codes were not
+    checked properly, this meant that the error returned might not be the
+    correct error, but would only occur in situations where an error was
+    already present.
+
+  * Fixed an issue whereby the SMP response function did not check to see if
+    the initial zcbor map was created successfully.
+
+  * Fixes an issue with MCUmgr shell_mgmt group whereby the length of a
+    received command was not properly checked.
+
+  * Added optional mutex locking support to MCUmgr img_mgmt group, which can
+    be enabled with :kconfig:option:`CONFIG_MCUMGR_GRP_IMG_MUTEX`.
+
+  * Added MCUmgr settings management group, which allows for manipulation of
+    zephyr settings from a remote device, see :ref:`mcumgr_smp_group_3` for
+    details.
+
+  * Added :kconfig:option:`CONFIG_MCUMGR_GRP_IMG_ALLOW_CONFIRM_NON_ACTIVE_IMAGE_SECONDARY`
+    and :kconfig:option:`CONFIG_MCUMGR_GRP_IMG_ALLOW_CONFIRM_NON_ACTIVE_IMAGE_ANY`
+    that allow to control whether MCUmgr client will be allowed to confirm
+    non-active images.
+
+  * Added :kconfig:option:`CONFIG_MCUMGR_GRP_IMG_ALLOW_ERASE_PENDING` that allows
+    to erase slots pending for next boot, that are not revert slots.
+
+* File systems
+
+  * Added support for ext2 file system.
+  * Added support of mounting littlefs on the block device from the shell/fs.
+  * Added alignment parameter to FS_LITTLEFS_DECLARE_CUSTOM_CONFIG macro, it can speed up read/write
+    operation for SDMMC devices in case when we align buffers on CONFIG_SDHC_BUFFER_ALIGNMENT,
+    because we can avoid extra copy of data from card bffer to read/prog buffer.
+
 HALs
 ****
 

subsys/shell/modules/CMakeLists.txt

@@ -16,3 +16,7 @@ zephyr_sources_ifdef(
   CONFIG_DEVMEM_SHELL
   devmem_service.c
   )
+zephyr_sources_ifdef(
+  CONFIG_APP_SHELL
+  app_service.c
+  )

subsys/shell/modules/Kconfig

@@ -45,3 +45,9 @@ config DEVMEM_SHELL
 	select GETOPT
 	help
 	  This shell command provides read/write access to physical memory.
+
+config APP_SHELL
+	bool "application shell (common to all applications)"
+	default y if !SHELL_MINIMAL
+	help
+	  This shell module provides access to common helpers.

subsys/shell/modules/app_service.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2023 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/sys/printk.h>
+#include <zephyr/shell/shell.h>
+#include <zephyr/init.h>
+#include <zephyr/kernel.h>
+#include <kernel_internal.h>
+#if defined(CONFIG_LOG_RUNTIME_FILTERING)
+#include <zephyr/logging/log_ctrl.h>
+#endif
+
+#include <malloc.h>
+
+static int cmd_app_heap(const struct shell *sh, size_t argc, char **argv)
+{
+#if __GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ < 33)
+	/* mallinfo() was deprecated in glibc 2.33 and removed in 2.34. */
+	struct mallinfo mi = mallinfo();
+#else
+	struct mallinfo2 mi = mallinfo2();
+#endif /* __GLIBC__ < 2 && (__GLIBC__ == 2 && __GLIBC_MINOR__ < 33) */
+
+	ARG_UNUSED(argc);
+	ARG_UNUSED(argv);
+
+	shell_print(sh, "Heap size: %d bytes", mi.arena);
+	shell_print(sh, "  used: %d bytes", mi.uordblks);
+	shell_print(sh, "  free: %d bytes", mi.fordblks);
+	shell_print(sh, "  max used: %d bytes", mi.usmblks);
+	shell_print(sh, "  free fastbin: %d bytes", mi.fsmblks);
+
+	return 0;
+}
+
+SHELL_STATIC_SUBCMD_SET_CREATE(sub_app,
+	SHELL_CMD(heap, NULL, "app heap", cmd_app_heap),
+	SHELL_SUBCMD_SET_END /* Array terminated. */
+);
+
+SHELL_CMD_REGISTER(app, &sub_app, "application commands", NULL);