Shell: Introduce shell_hexdump

This introduces shell_hexdump API which can be used to print an array
such as a network buffer.

Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: Vudentz

include/shell/shell.h

@@ -624,6 +624,15 @@ int shell_stop(const struct shell *shell);
 void shell_fprintf(const struct shell *shell, enum shell_vt100_color color,
 		   const char *fmt, ...);
 
+/**
+ * @brief Print data in hexadecimal format.
+ *
+ * @param[in] shell	Pointer to the shell instance.
+ * @param[in] data	Pointer to data.
+ * @param[in] len	Length of data.
+ */
+void shell_hexdump(const struct shell *shell, const u8_t *data, size_t len);
+
 /**
  * @brief Print info message to the shell.
  *

subsys/shell/shell.c

@@ -1355,6 +1355,28 @@ void shell_fprintf(const struct shell *shell, enum shell_vt100_color color,
 	k_mutex_unlock(&shell->ctx->wr_mtx);
 }
 
+void shell_hexdump(const struct shell *shell, const u8_t *data, size_t len)
+{
+	int n = 0;
+
+	while (len--) {
+		if (n % 16 == 0) {
+			shell_fprintf(shell, SHELL_NORMAL, "%08X: ", n);
+		}
+
+		shell_fprintf(shell, SHELL_NORMAL, "%02X ", *data++);
+
+		n++;
+		if (n % 16 == 0) {
+			shell_print(shell, "");
+		}
+	}
+
+	if (n % 16) {
+		shell_print(shell, "");
+	}
+}
+
 int shell_prompt_change(const struct shell *shell, const char *prompt)
 {
 	__ASSERT_NO_MSG(shell);