shell: Add wildcard support

Extended shell to support wildcard characters (*, ?) and expand commands
accordingly.

Sign-off-by: Jakub Rzeszutko <jakub.rzeszutko@nordicsemi.no>

subsys/shell/CMakeLists.txt

@@ -33,3 +33,8 @@ zephyr_sources_ifdef(
   CONFIG_LOG
   shell_log_backend.c
 )
+
+zephyr_sources_ifdef(
+  CONFIG_SHELL_WILDCARD
+  shell_wildcard.c
+)

subsys/shell/Kconfig

@@ -80,6 +80,12 @@ config SHELL_ARGC_MAX
 	  If command is composed of more than defined, argument SHELL_ARGC_MAX
 	  and follwing are passed as one argument in the string.
 
+config SHELL_WILDCARD
+	bool "Enable wildcard support in shell"
+	select FNMATCH
+	help
+	  Enables using * in shell.
+
 config SHELL_ECHO_STATUS
 	bool "Enable echo on shell"
 	default y

subsys/shell/shell.c

@@ -10,6 +10,7 @@
 #include <shell/shell.h>
 #include "shell_utils.h"
 #include "shell_ops.h"
+#include "shell_wildcard.h"
 #include "shell_vt100.h"
 #include <assert.h>
 #include <atomic.h>
@@ -385,6 +386,15 @@ static const struct shell_static_entry *get_last_command(
 	*match_arg = SHELL_CMD_ROOT_LVL;
 
 	while (*match_arg < argc) {
+
+		if (IS_ENABLED(CONFIG_SHELL_WILDCARD)) {
+			/* ignore wildcard argument */
+			if (shell_wildcard_character_exist(argv[*match_arg])) {
+				(*match_arg)++;
+				continue;
+			}
+		}
+
 		entry = find_cmd(prev_cmd, *match_arg, argv[*match_arg],
 				 d_entry);
 		if (entry) {
@@ -904,6 +914,7 @@ static void shell_execute(const struct shell *shell)
 	struct shell_cmd_entry const *p_cmd = NULL;
 	size_t cmd_lvl = SHELL_CMD_ROOT_LVL;
 	size_t cmd_with_handler_lvl = 0;
+	bool wildcard_found = false;
 	size_t cmd_idx;
 	size_t argc;
 	char quote;
@@ -915,6 +926,10 @@ static void shell_execute(const struct shell *shell)
 	history_put(shell, shell->ctx->cmd_buff,
 		    shell->ctx->cmd_buff_len);
 
+	if (IS_ENABLED(CONFIG_SHELL_WILDCARD)) {
+		shell_wildcard_prepare(shell);
+	}
+
 	shell_op_cursor_end_move(shell);
 	cursor_next_line_move(shell);
 
@@ -966,6 +981,27 @@ static void shell_execute(const struct shell *shell)
 			break;
 		}
 
+		if (IS_ENABLED(CONFIG_SHELL_WILDCARD)) {
+			enum shell_wildcard_status status;
+			status = shell_wildcard_process(shell, p_cmd,
+							 argv[cmd_lvl]);
+			/* Wildcard character found but there is no matching
+			 * command.
+			 */
+			if (status == SHELL_WILDCARD_CMD_NO_MATCH_FOUND) {
+				break;
+			}
+
+			/* Wildcard character was not found function can process
+			 * argument.
+			 */
+			if (status != SHELL_WILDCARD_NOT_FOUND) {
+				++cmd_lvl;
+				wildcard_found = true;
+				continue;
+			}
+		}
+
 		cmd_get(p_cmd, cmd_lvl, cmd_idx++, &p_static_entry, &d_entry);
 
 		if ((cmd_idx == 0) || (p_static_entry == NULL)) {
@@ -975,6 +1011,27 @@ static void shell_execute(const struct shell *shell)
 		if (strcmp(argv[cmd_lvl], p_static_entry->syntax) == 0) {
 			/* checking if command has a handler */
 			if (p_static_entry->handler != NULL) {
+				if (IS_ENABLED(CONFIG_SHELL_WILDCARD)) {
+					if (wildcard_found) {
+						shell_op_cursor_end_move(shell);
+						shell_op_cond_next_line(shell);
+
+						/* An error occurred, fnmatch
+						 * argument cannot be followed
+						 * by argument with a handler to
+						 * avoid multiple function
+						 * calls.
+						 */
+						shell_fprintf(shell,SHELL_ERROR,
+							"Error: requested "
+							"multiple function "
+							"executions\r\n");
+						flag_help_clear(shell);
+
+						return;
+					}
+				}
+
 				shell->ctx->active_cmd = *p_static_entry;
 				cmd_with_handler_lvl = cmd_lvl;
 			}
@@ -985,6 +1042,17 @@ static void shell_execute(const struct shell *shell)
 		}
 	}
 
+	if (IS_ENABLED(CONFIG_SHELL_WILDCARD)) {
+		shell_wildcard_finalize(shell);
+		/* cmd_buffer has been overwritten by function finalize function
+		 * with all expanded commands. Hence shell_make_argv needs to
+		 * be called again.
+		 */
+		(void)shell_make_argv(&argc, &argv[0],
+				      shell->ctx->cmd_buff,
+				      CONFIG_SHELL_ARGC_MAX);
+	}
+
 	/* Executing the deepest found handler. */
 	if (shell->ctx->active_cmd.handler == NULL) {
 		if (shell->ctx->active_cmd.help) {

subsys/shell/shell_wildcard.c

@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2018 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <string.h>
+#include <lib/fnmatch/fnmatch.h>
+#include "shell_wildcard.h"
+#include "shell_utils.h"
+
+static void subcmd_get(const struct shell_cmd_entry *cmd,
+		       size_t idx, const struct shell_static_entry **entry,
+		       struct shell_static_entry *d_entry) {
+	assert(entry != NULL);
+	assert(st_entry != NULL);
+
+	if (cmd == NULL) {
+		*entry = NULL;
+		return;
+	}
+
+	if (cmd->is_dynamic) {
+		cmd->u.dynamic_get(idx, d_entry);
+		*entry = (d_entry->syntax != NULL) ? d_entry : NULL;
+	} else {
+		*entry = (cmd->u.entry[idx].syntax != NULL) ?
+				&cmd->u.entry[idx] : NULL;
+	}
+}
+
+static enum shell_wildcard_status command_add(char *buff, u16_t *buff_len,
+					      char const *cmd,
+					      char const *pattern)
+{
+	u16_t cmd_len = shell_strlen(cmd);
+	char *completion_addr;
+	u16_t shift;
+
+	/* +1 for space */
+	if ((*buff_len + cmd_len + 1) > CONFIG_SHELL_CMD_BUFF_SIZE) {
+		return SHELL_WILDCARD_CMD_MISSING_SPACE;
+	}
+
+	completion_addr = strstr(buff, pattern);
+
+	if (!completion_addr) {
+		return SHELL_WILDCARD_CMD_NO_MATCH_FOUND;
+	}
+
+	shift = shell_strlen(completion_addr);
+
+	/* make place for new command: + 1 for space + 1 for EOS */
+	memmove(completion_addr + cmd_len + 1, completion_addr, shift + 1);
+	memcpy(completion_addr, cmd, cmd_len);
+	/* adding space to not brake next command in the buffer */
+	completion_addr[cmd_len] = ' ';
+
+	*buff_len += cmd_len + 1; // + 1 for space
+
+	return SHELL_WILDCARD_CMD_ADDED;
+}
+
+/**
+ * @internal @brief Function for searching and adding commands to the temporary
+ * shell buffer matching to wildcard pattern.
+ *
+ * This function is internal to shell module and shall be not called directly.
+ *
+ * @param[in/out] shell		Pointer to the CLI instance.
+ * @param[in]	  cmd		Pointer to command which will be processed
+ * @param[in]	  pattern	Pointer to wildcard pattern.
+ *
+ * @retval WILDCARD_CMD_ADDED	All matching commands added to the buffer.
+ * @retval WILDCARD_CMD_ADDED_MISSING_SPACE  Not all matching commands added
+ *					     because CONFIG_SHELL_CMD_BUFF_SIZE
+ *					     is too small.
+ * @retval WILDCARD_CMD_NO_MATCH_FOUND No matching command found.
+ */
+static enum shell_wildcard_status commands_expand(const struct shell *shell,
+					      const struct shell_cmd_entry *cmd,
+					      const char *pattern)
+{
+	enum shell_wildcard_status ret_val = SHELL_WILDCARD_CMD_NO_MATCH_FOUND;
+	struct shell_static_entry const * p_static_entry = NULL;
+	struct shell_static_entry static_entry;
+	size_t cmd_idx = 0;
+	size_t cnt = 0;
+
+	do {
+		subcmd_get(cmd, cmd_idx++, &p_static_entry, &static_entry);
+
+		if (!p_static_entry) {
+			break;
+		}
+
+		if (0 == fnmatch(pattern, p_static_entry->syntax, 0)) {
+			ret_val = command_add(shell->ctx->temp_buff,
+					      &shell->ctx->cmd_tmp_buff_len,
+					      p_static_entry->syntax, pattern);
+			if (ret_val == SHELL_WILDCARD_CMD_MISSING_SPACE) {
+				shell_fprintf(shell,
+					      SHELL_WARNING,
+					      "Command buffer is too short to"
+					      "expand all commands matching "
+					      "wildcard pattern: %s\r\n",
+					      pattern);
+				break;
+			} else if (ret_val != SHELL_WILDCARD_CMD_ADDED)
+			{
+				break;
+			}
+			cnt++;
+		}
+	} while(cmd_idx);
+
+	if (cnt > 0)
+	{
+		shell_pattern_remove(shell->ctx->temp_buff,
+				     &shell->ctx->cmd_tmp_buff_len, pattern);
+	}
+
+	return ret_val;
+}
+
+bool shell_wildcard_character_exist(const char *str)
+{
+	size_t str_len = shell_strlen(str);
+
+	for (size_t i = 0; i < str_len; i++) {
+		if ((str[i] == '?') || (str[i] == '*')) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+void shell_wildcard_prepare(const struct shell *shell)
+{
+	/* Wildcard can be correctly handled under following conditions:
+	 * - wildcard command does not have a handler
+	 * - wildcard command is on the deepest commands level
+	 * - other commands on the same level as wildcard command shall also not
+	 *   have a handler
+	 *
+	 * Algorithm:
+	 * 1. Command buffer is copied to Temp buffer.
+	 * 2. Algorithm goes through Command buffer to find handlers and
+	 *    subcommands.
+	 * 3. If algorithm will find a wildcard character it switches to Temp
+	 *    buffer.
+	 * 4. In the Temp buffer command with found wildcard character is
+	 *    changed into matching command(s).
+	 * 5. Algorithm switch back to Command buffer and analyzes next command.
+	 * 6. When all arguments are analyzed from Command buffer, Temp buffer
+	 *    is copied to Command buffer.
+	 * 7. Last found handler is executed with all arguments in the Command
+	 *    buffer.
+	 */
+
+	memset(shell->ctx->temp_buff, 0, sizeof(shell->ctx->temp_buff));
+	memcpy(shell->ctx->temp_buff,
+			shell->ctx->cmd_buff,
+			shell->ctx->cmd_buff_len);
+
+	/* Function shell_spaces_trim must be used instead of shell_make_argv.
+	 * At this point it is important to keep temp_buff as a one string.
+	 * It will allow to find wildcard commands easily with strstr function.
+	 */
+	shell_spaces_trim(shell->ctx->temp_buff);
+
+	/* +1 for EOS*/
+	shell->ctx->cmd_tmp_buff_len = shell_strlen(shell->ctx->temp_buff) + 1;
+}
+
+
+enum shell_wildcard_status shell_wildcard_process(const struct shell *shell,
+					      const struct shell_cmd_entry *cmd,
+					      const char *pattern)
+{
+	enum shell_wildcard_status ret_val = SHELL_WILDCARD_NOT_FOUND;
+
+	if (cmd == NULL) {
+		return ret_val;
+	}
+
+	if (!shell_wildcard_character_exist(pattern)) {
+		return ret_val;
+	}
+
+	/* Function will search commands tree for commands matching wildcard
+	 * pattern stored in argv[cmd_lvl]. If match is found wildcard pattern
+	 * will be replaced by matching commands in temp_buffer. If there is no
+	 * space to add all matching commands function will add as many as
+	 * possible. Next it will continue to search for next wildcard pattern
+	 * and it will try to add matching commands.
+	 */
+	ret_val = commands_expand(shell, cmd, pattern);
+
+	return ret_val;
+}
+
+void shell_wildcard_finalize(const struct shell *shell)
+{
+	memcpy(shell->ctx->cmd_buff,
+	       shell->ctx->temp_buff,
+	       shell->ctx->cmd_tmp_buff_len);
+	shell->ctx->cmd_buff_len = shell->ctx->cmd_tmp_buff_len;
+}

subsys/shell/shell_wildcard.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef SHELL_SHELL_WILDCARDS_H__
+#define SHELL_SHELL_WILDCARDS_H__
+
+#include <shell/shell.h>
+
+enum shell_wildcard_status {
+	SHELL_WILDCARD_CMD_ADDED,
+	SHELL_WILDCARD_CMD_MISSING_SPACE,
+	SHELL_WILDCARD_CMD_NO_MATCH_FOUND, /* no matching command */
+	SHELL_WILDCARD_NOT_FOUND /* wildcard character not found */
+};
+
+
+bool shell_wildcard_character_exist(const char *str);
+
+void shell_wildcard_prepare(const struct shell *shell);
+
+/* Function expands wildcards in the shell temporary buffer */
+enum shell_wildcard_status shell_wildcard_process(const struct shell *shell,
+					      const struct shell_cmd_entry *cmd,
+					      const char *pattern);
+
+void shell_wildcard_finalize(const struct shell *shell);
+
+
+#endif /* SHELL_SHELL_WILDCARDS_H__ */