command.c

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// SPDX-License-Identifier: GPL-2.0-or-later
 
/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
 *   oyvind.harboe@zylin.com                                               *
 *                                                                         *
 *   Copyright (C) 2008, Duane Ellis                                       *
 *   openocd@duaneeellis.com                                               *
 *                                                                         *
 *   part of this file is taken from libcli (libcli.sourceforge.net)       *
 *   Copyright (C) David Parrish (david@dparrish.com)                      *
 ***************************************************************************/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
/* @todo the inclusion of target.h here is a layering violation */
#include <jtag/jtag.h>
#include <target/target.h>
#include "command.h"
#include "configuration.h"
#include "log.h"
#include "time_support.h"
#include "jim-eventloop.h"
 
/* nice short description of source file */
#define __THIS__FILE__ "command.c"
 
struct log_capture_state {
    char *output;
};
 
static int unregister_command(struct command_context *context,
    const char *cmd_prefix, const char *name);
static int jim_command_dispatch(Jim_Interp *interp, int argc, Jim_Obj * const *argv);
static int help_add_command(struct command_context *cmd_ctx,
    const char *cmd_name, const char *help_text, const char *usage_text);
static int help_del_command(struct command_context *cmd_ctx, const char *cmd_name);
static enum command_mode get_command_mode(Jim_Interp *interp, const char *cmd_name);
 
/* set of functions to wrap jimtcl internal data */
static inline bool jimcmd_is_proc(Jim_Cmd *cmd)
{
#if defined(JIM_CMD_ISPROC)
    // JIM_VERSION >= 84
    return cmd->flags & JIM_CMD_ISPROC;
#else
    return cmd->isproc;
#endif
}
 
bool jimcmd_is_oocd_command(Jim_Cmd *cmd)
{
    return !jimcmd_is_proc(cmd) && cmd->u.native.cmdProc == jim_command_dispatch;
}
 
void *jimcmd_privdata(Jim_Cmd *cmd)
{
    return jimcmd_is_proc(cmd) ? NULL : cmd->u.native.privData;
}
 
extern struct command_context *global_cmd_ctx;
 
/* dump a single line to the log for the command.
 * Do nothing in case we are not at debug level 3 */
static void script_debug(Jim_Interp *interp, unsigned int argc, Jim_Obj * const *argv)
{
    if (debug_level < LOG_LVL_DEBUG)
        return;
 
    char *dbg = alloc_printf("command -");
    for (unsigned int i = 0; i < argc; i++) {
        const char *w = Jim_GetString(argv[i], NULL);
        char *t = alloc_printf("%s %s", dbg, w);
        free(dbg);
        dbg = t;
    }
    LOG_DEBUG("%s", dbg);
    free(dbg);
}
 
struct command_context *current_command_context(Jim_Interp *interp)
{
    /* grab the command context from the associated data */
    struct command_context *cmd_ctx = Jim_GetAssocData(interp, "context");
    if (!cmd_ctx) {
        /* Tcl can invoke commands directly instead of via command_run_line(). This would
         * happen when the Jim Tcl interpreter is provided by eCos or if we are running
         * commands in a startup script.
         *
         * A telnet or gdb server would provide a non-default command context to
         * handle piping of error output, have a separate current target, etc.
         */
        cmd_ctx = global_cmd_ctx;
    }
    return cmd_ctx;
}
 
static struct command *command_find_from_name(Jim_Interp *interp, const char *name)
{
    if (!name)
        return NULL;
 
    Jim_Obj *jim_name = Jim_NewStringObj(interp, name, -1);
    Jim_IncrRefCount(jim_name);
    Jim_Cmd *cmd = Jim_GetCommand(interp, jim_name, JIM_NONE);
    Jim_DecrRefCount(interp, jim_name);
    if (!cmd || jimcmd_is_proc(cmd) || !jimcmd_is_oocd_command(cmd))
        return NULL;
 
    return jimcmd_privdata(cmd);
}
 
static struct command *command_new(struct command_context *cmd_ctx,
    const char *full_name, const struct command_registration *cr)
{
    assert(cr->name);
 
    /*
     * If it is a command with no .usage specified,
     * log an error.
     *
     * strlen(.usage) == 0 means that the command takes no
     * arguments.
    */
    if (!cr->usage)
        LOG_ERROR("BUG: command '%s' does not have the "
            "'.usage' field filled out",
            full_name);
 
    struct command *c = calloc(1, sizeof(struct command));
    if (!c)
        return NULL;
 
    c->name = strdup(cr->name);
    if (!c->name) {
        free(c);
        return NULL;
    }
 
    c->handler = cr->handler;
    c->mode = cr->mode;
 
    if (cr->help || cr->usage)
        help_add_command(cmd_ctx, full_name, cr->help, cr->usage);
 
    return c;
}
 
static void command_free(struct Jim_Interp *interp, void *priv)
{
    struct command *c = priv;
 
    free(c->name);
    free(c);
}
 
static struct command *register_command(struct command_context *context,
    const char *cmd_prefix, const struct command_registration *cr)
{
    char *full_name;
 
    if (!context || !cr->name)
        return NULL;
 
    if (cmd_prefix)
        full_name = alloc_printf("%s %s", cmd_prefix, cr->name);
    else
        full_name = strdup(cr->name);
    if (!full_name)
        return NULL;
 
    struct command *c = command_find_from_name(context->interp, full_name);
    if (c) {
        /* TODO: originally we treated attempting to register a cmd twice as an error
         * Sometimes we need this behaviour, such as with flash banks.
         * http://www.mail-archive.com/openocd-development@lists.berlios.de/msg11152.html */
        LOG_DEBUG("command '%s' is already registered", full_name);
        free(full_name);
        return c;
    }
 
    c = command_new(context, full_name, cr);
    if (!c) {
        free(full_name);
        return NULL;
    }
 
    if (false) /* too noisy with debug_level 3 */
        LOG_DEBUG("registering '%s'...", full_name);
    int retval = Jim_CreateCommand(context->interp, full_name,
                jim_command_dispatch, c, command_free);
    if (retval != JIM_OK) {
        command_run_linef(context, "del_help_text {%s}", full_name);
        command_run_linef(context, "del_usage_text {%s}", full_name);
        free(c);
        free(full_name);
        return NULL;
    }
 
    free(full_name);
    return c;
}
 
int __register_commands(struct command_context *cmd_ctx, const char *cmd_prefix,
    const struct command_registration *cmds, void *data,
    struct target *override_target)
{
    int retval = ERROR_OK;
    unsigned int i;
    for (i = 0; cmds[i].name || cmds[i].chain; i++) {
        const struct command_registration *cr = cmds + i;
 
        struct command *c = NULL;
        if (cr->name) {
            c = register_command(cmd_ctx, cmd_prefix, cr);
            if (!c) {
                retval = ERROR_FAIL;
                break;
            }
            c->jim_handler_data = data;
            c->jim_override_target = override_target;
        }
        if (cr->chain) {
            if (cr->name) {
                if (cmd_prefix) {
                    char *new_prefix = alloc_printf("%s %s", cmd_prefix, cr->name);
                    if (!new_prefix) {
                        retval = ERROR_FAIL;
                        break;
                    }
                    retval = __register_commands(cmd_ctx, new_prefix, cr->chain, data, override_target);
                    free(new_prefix);
                } else {
                    retval = __register_commands(cmd_ctx, cr->name, cr->chain, data, override_target);
                }
            } else {
                retval = __register_commands(cmd_ctx, cmd_prefix, cr->chain, data, override_target);
            }
            if (retval != ERROR_OK)
                break;
        }
    }
    if (retval != ERROR_OK) {
        for (unsigned int j = 0; j < i; j++)
            unregister_command(cmd_ctx, cmd_prefix, cmds[j].name);
    }
    return retval;
}
 
static __attribute__ ((format (PRINTF_ATTRIBUTE_FORMAT, 2, 3)))
int unregister_commands_match(struct command_context *cmd_ctx, const char *format, ...)
{
    Jim_Interp *interp = cmd_ctx->interp;
    va_list ap;
 
    va_start(ap, format);
    char *query = alloc_vprintf(format, ap);
    va_end(ap);
    if (!query)
        return ERROR_FAIL;
 
    char *query_cmd = alloc_printf("info commands {%s}", query);
    free(query);
    if (!query_cmd)
        return ERROR_FAIL;
 
    int retval = Jim_EvalSource(interp, __THIS__FILE__, __LINE__, query_cmd);
    free(query_cmd);
    if (retval != JIM_OK)
        return ERROR_FAIL;
 
    Jim_Obj *list = Jim_GetResult(interp);
    Jim_IncrRefCount(list);
 
    int len = Jim_ListLength(interp, list);
    for (int i = 0; i < len; i++) {
        Jim_Obj *elem = Jim_ListGetIndex(interp, list, i);
        Jim_IncrRefCount(elem);
 
        const char *name = Jim_GetString(elem, NULL);
        struct command *c = command_find_from_name(interp, name);
        if (!c) {
            /* not openocd command */
            Jim_DecrRefCount(interp, elem);
            continue;
        }
        if (false) /* too noisy with debug_level 3 */
            LOG_DEBUG("delete command \"%s\"", name);
#if JIM_VERSION >= 80
        Jim_DeleteCommand(interp, elem);
#else
        Jim_DeleteCommand(interp, name);
#endif
 
        help_del_command(cmd_ctx, name);
 
        Jim_DecrRefCount(interp, elem);
    }
 
    Jim_DecrRefCount(interp, list);
    return ERROR_OK;
}
 
int unregister_all_commands(struct command_context *context,
    const char *cmd_prefix)
{
    if (!context)
        return ERROR_OK;
 
    if (!cmd_prefix || !*cmd_prefix)
        return unregister_commands_match(context, "*");
 
    int retval = unregister_commands_match(context, "%s *", cmd_prefix);
    if (retval != ERROR_OK)
        return retval;
 
    return unregister_commands_match(context, "%s", cmd_prefix);
}
 
static int unregister_command(struct command_context *context,
    const char *cmd_prefix, const char *name)
{
    if (!context || !name)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    if (!cmd_prefix || !*cmd_prefix)
        return unregister_commands_match(context, "%s", name);
 
    return unregister_commands_match(context, "%s %s", cmd_prefix, name);
}
 
void command_output_text(struct command_context *context, const char *data)
{
    if (context && context->output_handler && data)
        context->output_handler(context, data);
}
 
void command_print_sameline(struct command_invocation *cmd, const char *format, ...)
{
    char *string;
 
    va_list ap;
    va_start(ap, format);
 
    string = alloc_vprintf(format, ap);
    if (string && cmd) {
        /* we want this collected in the log + we also want to pick it up as a tcl return
         * value.
         *
         * The latter bit isn't precisely neat, but will do for now.
         */
        Jim_AppendString(cmd->ctx->interp, cmd->output, string, -1);
        /* We already printed it above
         * command_output_text(context, string); */
        free(string);
    }
 
    va_end(ap);
}
 
void command_print(struct command_invocation *cmd, const char *format, ...)
{
    char *string;
 
    va_list ap;
    va_start(ap, format);
 
    string = alloc_vprintf(format, ap);
    if (string && cmd) {
        strcat(string, "\n");   /* alloc_vprintf guaranteed the buffer to be at least one
                     *char longer */
        /* we want this collected in the log + we also want to pick it up as a tcl return
         * value.
         *
         * The latter bit isn't precisely neat, but will do for now.
         */
        Jim_AppendString(cmd->ctx->interp, cmd->output, string, -1);
        /* We already printed it above
         * command_output_text(context, string); */
        free(string);
    }
 
    va_end(ap);
}
 
static bool command_can_run(struct command_context *cmd_ctx, struct command *c, const char *full_name)
{
    if (c->mode == COMMAND_ANY || c->mode == cmd_ctx->mode)
        return true;
 
    /* Many commands may be run only before/after 'init' */
    const char *when;
    switch (c->mode) {
        case COMMAND_CONFIG:
            when = "before";
            break;
        case COMMAND_EXEC:
            when = "after";
            break;
        /* handle the impossible with humor; it guarantees a bug report! */
        default:
            when = "if Cthulhu is summoned by";
            break;
    }
    LOG_ERROR("The '%s' command must be used %s 'init'.",
            full_name ? full_name : c->name, when);
    return false;
}
 
static int jim_exec_command(Jim_Interp *interp, struct command_context *context,
        struct command *c, int argc, Jim_Obj * const *argv)
{
    /* use c->handler */
    const char **words = malloc(argc * sizeof(char *));
    if (!words) {
        LOG_ERROR("Out of memory");
        return JIM_ERR;
    }
 
    for (int i = 0; i < argc; i++)
        words[i] = Jim_GetString(argv[i], NULL);
 
    struct command_invocation cmd = {
        .ctx = context,
        .current = c,
        .name = c->name,
        .argc = argc - 1,
        .argv = words + 1,
        .jimtcl_argv = argv + 1,
    };
 
    cmd.output = Jim_NewEmptyStringObj(context->interp);
    Jim_IncrRefCount(cmd.output);
 
    int retval = c->handler(&cmd);
    if (retval == ERROR_COMMAND_SYNTAX_ERROR) {
        /* Print help for command */
        command_run_linef(context, "usage %s", words[0]);
    } else if (retval == ERROR_COMMAND_CLOSE_CONNECTION) {
        /* just fall through for a shutdown request */
    } else {
        if (retval != ERROR_OK)
            LOG_DEBUG("Command '%s' failed with error code %d",
                        words[0], retval);
        /*
         * Use the command output as the Tcl result.
         * Drop last '\n' to allow command output concatenation
         * while keep using command_print() everywhere.
         */
        const char *output_txt = Jim_String(cmd.output);
        int len = strlen(output_txt);
        if (len && output_txt[len - 1] == '\n')
            --len;
        Jim_SetResultString(context->interp, output_txt, len);
    }
    Jim_DecrRefCount(context->interp, cmd.output);
 
    free(words);
 
    if (retval == ERROR_OK)
        return JIM_OK;
 
    // used by telnet server to close one connection
    if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
        return JIM_EXIT;
 
    return JIM_ERR;
}
 
int command_run_line(struct command_context *context, char *line)
{
    /* all the parent commands have been registered with the interpreter
     * so, can just evaluate the line as a script and check for
     * results
     */
    /* run the line thru a script engine */
    int retcode;
    /* Beware! This code needs to be reentrant. It is also possible
     * for OpenOCD commands to be invoked directly from Tcl. This would
     * happen when the Jim Tcl interpreter is provided by eCos for
     * instance.
     */
    struct target *saved_target_override = context->current_target_override;
    context->current_target_override = NULL;
 
    Jim_Interp *interp = context->interp;
    struct command_context *old_context = Jim_GetAssocData(interp, "context");
    Jim_DeleteAssocData(interp, "context");
    retcode = Jim_SetAssocData(interp, "context", NULL, context);
    if (retcode == JIM_OK) {
        retcode = Jim_Eval_Named(interp, line, NULL, 0);
        Jim_DeleteAssocData(interp, "context");
        int inner_retcode = Jim_SetAssocData(interp, "context", NULL, old_context);
        if (retcode == JIM_OK)
            retcode = inner_retcode;
    }
    context->current_target_override = saved_target_override;
 
    if (retcode == JIM_RETURN)
        retcode = interp->returnCode;
 
    if (retcode == JIM_OK) {
        const char *result;
        int reslen;
 
        result = Jim_GetString(Jim_GetResult(interp), &reslen);
        if (reslen > 0) {
            command_output_text(context, result);
            command_output_text(context, "\n");
        }
        return ERROR_OK;
    }
 
    if (retcode == JIM_EXIT) {
        // used by telnet server to close one connection
        return ERROR_COMMAND_CLOSE_CONNECTION;
    }
 
    Jim_MakeErrorMessage(interp);
    /* error is broadcast */
    LOG_USER("%s", Jim_GetString(Jim_GetResult(interp), NULL));
 
    return ERROR_FAIL;
}
 
int command_run_linef(struct command_context *context, const char *format, ...)
{
    int retval = ERROR_FAIL;
    char *string;
    va_list ap;
    va_start(ap, format);
    string = alloc_vprintf(format, ap);
    if (string) {
        retval = command_run_line(context, string);
        free(string);
    }
    va_end(ap);
    return retval;
}
 
void command_set_output_handler(struct command_context *context,
    command_output_handler_t output_handler, void *priv)
{
    context->output_handler = output_handler;
    context->output_handler_priv = priv;
}
 
struct command_context *copy_command_context(struct command_context *context)
{
    struct command_context *copy_context = malloc(sizeof(struct command_context));
 
    *copy_context = *context;
 
    return copy_context;
}
 
void command_done(struct command_context *cmd_ctx)
{
    if (!cmd_ctx)
        return;
 
    free(cmd_ctx);
}
 
/* find full path to file */
COMMAND_HANDLER(handle_find)
{
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    char *full_path = find_file(CMD_ARGV[0]);
    if (!full_path)
        return ERROR_COMMAND_ARGUMENT_INVALID;
 
    command_print(CMD, "%s", full_path);
    free(full_path);
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(handle_echo)
{
    if (CMD_ARGC == 2 && !strcmp(CMD_ARGV[0], "-n")) {
        LOG_USER_N("%s", CMD_ARGV[1]);
        return ERROR_OK;
    }
 
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    LOG_USER("%s", CMD_ARGV[0]);
    return ERROR_OK;
}
 
static void tcl_output(void *privData, const char *file, unsigned int line,
    const char *function, const char *string)
{
    struct log_capture_state *state = privData;
    char *old = state->output;
 
    state->output = alloc_printf("%s%s", old ? old : "", string);
    free(old);
    if (!state->output)
        LOG_ERROR("Out of memory");
}
 
/*
 * Return both the progress output (LOG_INFO and higher)
 * and the tcl return value of a command.
 */
COMMAND_HANDLER(handle_command_capture)
{
    struct log_capture_state state = {NULL};
 
    if (CMD_ARGC != 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    /* disable polling during capture. This avoids capturing output
     * from polling.
     *
     * This is necessary in order to avoid accidentally getting a non-empty
     * string for tcl fn's.
     */
    bool save_poll_mask = jtag_poll_mask();
 
    log_add_callback(tcl_output, &state);
 
    int jimretval = Jim_EvalObj(CMD_CTX->interp, CMD_JIMTCL_ARGV[0]);
    const char *cmd_result = Jim_GetString(Jim_GetResult(CMD_CTX->interp), NULL);
 
    log_remove_callback(tcl_output, &state);
 
    jtag_poll_unmask(save_poll_mask);
 
    if (state.output && *state.output)
        command_print(CMD, "%s", state.output);
 
    if (cmd_result && *cmd_result)
        command_print(CMD, "%s", cmd_result);
 
    free(state.output);
 
    return (jimretval == JIM_OK) ? ERROR_OK : ERROR_FAIL;
}
 
struct help_entry {
    struct list_head lh;
    char *cmd_name;
    char *help;
    char *usage;
};
 
static COMMAND_HELPER(command_help_show, struct help_entry *c,
    bool show_help, const char *cmd_match);
 
static COMMAND_HELPER(command_help_show_list, bool show_help, const char *cmd_match)
{
    struct help_entry *entry;
 
    list_for_each_entry(entry, CMD_CTX->help_list, lh)
        CALL_COMMAND_HANDLER(command_help_show, entry, show_help, cmd_match);
    return ERROR_OK;
}
 
#define HELP_LINE_WIDTH(_n) (int)(76 - (2 * _n))
 
static void command_help_show_indent(unsigned int n)
{
    for (unsigned int i = 0; i < n; i++)
        LOG_USER_N("  ");
}
static void command_help_show_wrap(const char *str, unsigned int n, unsigned int n2)
{
    const char *cp = str, *last = str;
    while (*cp) {
        const char *next = last;
        do {
            cp = next;
            do {
                next++;
            } while (*next != ' ' && *next != '\t' && *next != '\0');
        } while ((next - last < HELP_LINE_WIDTH(n)) && *next != '\0');
        if (next - last < HELP_LINE_WIDTH(n))
            cp = next;
        command_help_show_indent(n);
        LOG_USER("%.*s", (int)(cp - last), last);
        last = cp + 1;
        n = n2;
    }
}
 
static COMMAND_HELPER(command_help_show, struct help_entry *c,
    bool show_help, const char *cmd_match)
{
    unsigned int n = 0;
    for (const char *s = strchr(c->cmd_name, ' '); s; s = strchr(s + 1, ' '))
        n++;
 
    /* If the match string occurs anywhere, we print out
     * stuff for this command. */
    bool is_match = strstr(c->cmd_name, cmd_match) ||
        (c->usage && strstr(c->usage, cmd_match)) ||
        (c->help && strstr(c->help, cmd_match));
 
    if (is_match) {
        if (c->usage && strlen(c->usage) > 0) {
            char *msg = alloc_printf("%s %s", c->cmd_name, c->usage);
            command_help_show_wrap(msg, n, n + 5);
            free(msg);
        } else {
            command_help_show_wrap(c->cmd_name, n, n + 5);
        }
    }
 
    if (is_match && show_help) {
        char *msg;
 
        enum command_mode mode = get_command_mode(CMD_CTX->interp, c->cmd_name);
 
        /* Normal commands are runtime-only; highlight exceptions */
        if (mode != COMMAND_EXEC) {
            const char *stage_msg = "";
 
            switch (mode) {
                case COMMAND_CONFIG:
                    stage_msg = " (configuration command)";
                    break;
                case COMMAND_ANY:
                    stage_msg = " (command valid any time)";
                    break;
                case COMMAND_UNKNOWN:
                default:
                    stage_msg = " (?mode error?)";
                    break;
            }
            msg = alloc_printf("%s%s", c->help ? c->help : "", stage_msg);
        } else
            msg = alloc_printf("%s", c->help ? c->help : "");
 
        if (!msg) {
            LOG_ERROR("Out of memory");
            return ERROR_FAIL;
        }
 
        command_help_show_wrap(msg, n + 3, n + 3);
        free(msg);
    }
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(handle_help_command)
{
    bool full = strcmp(CMD_NAME, "help") == 0;
    int retval;
    char *cmd_match;
 
    if (CMD_ARGC <= 0)
        cmd_match = strdup("");
 
    else {
        cmd_match = strdup(CMD_ARGV[0]);
 
        for (unsigned int i = 1; i < CMD_ARGC && cmd_match; ++i) {
            char *prev = cmd_match;
            cmd_match = alloc_printf("%s %s", prev, CMD_ARGV[i]);
            free(prev);
        }
    }
 
    if (!cmd_match) {
        LOG_ERROR("unable to build search string");
        return -ENOMEM;
    }
    retval = CALL_COMMAND_HANDLER(command_help_show_list, full, cmd_match);
 
    free(cmd_match);
    return retval;
}
 
static char *alloc_concatenate_strings(int argc, const char **argv)
{
    assert(argc >= 1);
 
    char *all = strdup(argv[0]);
    if (!all) {
        LOG_ERROR("Out of memory");
        return NULL;
    }
 
    for (int i = 1; i < argc; ++i) {
        char *prev = all;
        all = alloc_printf("%s %s", all, argv[i]);
        free(prev);
        if (!all) {
            LOG_ERROR("Out of memory");
            return NULL;
        }
    }
 
    return all;
}
 
static int jim_command_dispatch(Jim_Interp *interp, int argc, Jim_Obj * const *argv)
{
    /* check subcommands */
    if (argc > 1) {
        char *s = alloc_printf("%s %s", Jim_GetString(argv[0], NULL), Jim_GetString(argv[1], NULL));
        Jim_Obj *js = Jim_NewStringObj(interp, s, -1);
        Jim_IncrRefCount(js);
        free(s);
        Jim_Cmd *cmd = Jim_GetCommand(interp, js, JIM_NONE);
        if (cmd) {
            int retval = Jim_EvalObjPrefix(interp, js, argc - 2, argv + 2);
            Jim_DecrRefCount(interp, js);
            return retval;
        }
        Jim_DecrRefCount(interp, js);
    }
 
    script_debug(interp, argc, argv);
 
    struct command *c = jim_to_command(interp);
    if (!c->handler) {
        Jim_EvalObjPrefix(interp, Jim_NewStringObj(interp, "usage", -1), 1, argv);
        return JIM_ERR;
    }
 
    struct command_context *cmd_ctx = current_command_context(interp);
 
    if (!command_can_run(cmd_ctx, c, Jim_GetString(argv[0], NULL)))
        return JIM_ERR;
 
    target_call_timer_callbacks();
 
    /*
     * Black magic of overridden current target:
     * If the command we are going to handle has a target prefix,
     * override the current target temporarily for the time
     * of processing the command.
     * current_target_override is used also for event handlers
     * therefore we prevent touching it if command has no prefix.
     * Previous override is saved and restored back to ensure
     * correct work when jim_command_dispatch() is re-entered.
     */
    struct target *saved_target_override = cmd_ctx->current_target_override;
    if (c->jim_override_target)
        cmd_ctx->current_target_override = c->jim_override_target;
 
    int retval = jim_exec_command(interp, cmd_ctx, c, argc, argv);
 
    if (c->jim_override_target)
        cmd_ctx->current_target_override = saved_target_override;
 
    return retval;
}
 
static enum command_mode get_command_mode(Jim_Interp *interp, const char *cmd_name)
{
    if (!cmd_name)
        return COMMAND_UNKNOWN;
 
    Jim_Obj *s = Jim_NewStringObj(interp, cmd_name, -1);
    Jim_IncrRefCount(s);
    Jim_Cmd *cmd = Jim_GetCommand(interp, s, JIM_NONE);
    Jim_DecrRefCount(interp, s);
 
    if (!cmd || !(jimcmd_is_proc(cmd) || jimcmd_is_oocd_command(cmd)))
        return COMMAND_UNKNOWN;
 
    /* tcl proc */
    if (jimcmd_is_proc(cmd))
        return COMMAND_ANY;
 
    struct command *c = jimcmd_privdata(cmd);
    return c->mode;
}
 
COMMAND_HANDLER(handle_command_mode)
{
    enum command_mode mode = CMD_CTX->mode;
 
    if (CMD_ARGC) {
        char *full_name = alloc_concatenate_strings(CMD_ARGC, CMD_ARGV);
        if (!full_name)
            return ERROR_FAIL;
 
        mode = get_command_mode(CMD_CTX->interp, full_name);
 
        free(full_name);
    }
 
    const char *mode_str;
    switch (mode) {
        case COMMAND_ANY:
            mode_str = "any";
            break;
        case COMMAND_CONFIG:
            mode_str = "config";
            break;
        case COMMAND_EXEC:
            mode_str = "exec";
            break;
        case COMMAND_UNKNOWN:
        default:
            mode_str = "unknown";
            break;
    }
    command_print(CMD, "%s", mode_str);
    return ERROR_OK;
}
 
int help_del_all_commands(struct command_context *cmd_ctx)
{
    struct help_entry *curr, *n;
 
    list_for_each_entry_safe(curr, n, cmd_ctx->help_list, lh) {
        list_del(&curr->lh);
        free(curr->cmd_name);
        free(curr->help);
        free(curr->usage);
        free(curr);
    }
    return ERROR_OK;
}
 
static int help_del_command(struct command_context *cmd_ctx, const char *cmd_name)
{
    struct help_entry *curr;
 
    list_for_each_entry(curr, cmd_ctx->help_list, lh) {
        if (!strcmp(cmd_name, curr->cmd_name)) {
            list_del(&curr->lh);
            free(curr->cmd_name);
            free(curr->help);
            free(curr->usage);
            free(curr);
            break;
        }
    }
 
    return ERROR_OK;
}
 
static int help_add_command(struct command_context *cmd_ctx,
    const char *cmd_name, const char *help_text, const char *usage_text)
{
    int cmp = -1; /* add after curr */
    struct help_entry *curr;
 
    list_for_each_entry_reverse(curr, cmd_ctx->help_list, lh) {
        cmp = strcmp(cmd_name, curr->cmd_name);
        if (cmp >= 0)
            break;
    }
 
    struct help_entry *entry;
    if (cmp) {
        entry = calloc(1, sizeof(*entry));
        if (!entry) {
            LOG_ERROR("Out of memory");
            return ERROR_FAIL;
        }
        entry->cmd_name = strdup(cmd_name);
        if (!entry->cmd_name) {
            LOG_ERROR("Out of memory");
            free(entry);
            return ERROR_FAIL;
        }
        list_add(&entry->lh, &curr->lh);
    } else {
        entry = curr;
    }
 
    if (help_text) {
        char *text = strdup(help_text);
        if (!text) {
            LOG_ERROR("Out of memory");
            return ERROR_FAIL;
        }
        free(entry->help);
        entry->help = text;
    }
 
    if (usage_text) {
        char *text = strdup(usage_text);
        if (!text) {
            LOG_ERROR("Out of memory");
            return ERROR_FAIL;
        }
        free(entry->usage);
        entry->usage = text;
    }
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(handle_help_add_command)
{
    if (CMD_ARGC != 2)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    const char *help = !strcmp(CMD_NAME, "add_help_text") ? CMD_ARGV[1] : NULL;
    const char *usage = !strcmp(CMD_NAME, "add_usage_text") ? CMD_ARGV[1] : NULL;
    if (!help && !usage) {
        LOG_ERROR("command name '%s' is unknown", CMD_NAME);
        return ERROR_COMMAND_SYNTAX_ERROR;
    }
    const char *cmd_name = CMD_ARGV[0];
    return help_add_command(CMD_CTX, cmd_name, help, usage);
}
 
/* sleep command sleeps for <n> milliseconds
 * this is useful in target startup scripts
 */
COMMAND_HANDLER(handle_sleep_command)
{
    bool busy = false;
    if (CMD_ARGC == 2) {
        if (strcmp(CMD_ARGV[1], "busy") == 0)
            busy = true;
        else
            return ERROR_COMMAND_SYNTAX_ERROR;
    } else if (CMD_ARGC < 1 || CMD_ARGC > 2)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    unsigned long duration = 0;
    int retval = parse_ulong(CMD_ARGV[0], &duration);
    if (retval != ERROR_OK)
        return retval;
 
    if (!busy) {
        int64_t then = timeval_ms();
        while (timeval_ms() - then < (int64_t)duration) {
            target_call_timer_callbacks_now();
            keep_alive();
            usleep(1000);
        }
    } else
        busy_sleep(duration);
 
    return ERROR_OK;
}
 
static const struct command_registration command_subcommand_handlers[] = {
    {
        .name = "mode",
        .mode = COMMAND_ANY,
        .handler = handle_command_mode,
        .usage = "[command_name ...]",
        .help = "Returns the command modes allowed by a command: "
            "'any', 'config', or 'exec'. If no command is "
            "specified, returns the current command mode. "
            "Returns 'unknown' if an unknown command is given. "
            "Command can be multiple tokens.",
    },
    COMMAND_REGISTRATION_DONE
};
 
static const struct command_registration command_builtin_handlers[] = {
    {
        .name = "ocd_find",
        .mode = COMMAND_ANY,
        .handler = handle_find,
        .help = "find full path to file",
        .usage = "file",
    },
    {
        .name = "capture",
        .mode = COMMAND_ANY,
        .handler = handle_command_capture,
        .help = "Capture progress output and return as tcl return value. If the "
                "progress output was empty, return tcl return value.",
        .usage = "command",
    },
    {
        .name = "echo",
        .handler = handle_echo,
        .mode = COMMAND_ANY,
        .help = "Logs a message at \"user\" priority. "
            "Option \"-n\" suppresses trailing newline",
        .usage = "[-n] string",
    },
    {
        .name = "add_help_text",
        .handler = handle_help_add_command,
        .mode = COMMAND_ANY,
        .help = "Add new command help text; "
            "Command can be multiple tokens.",
        .usage = "command_name helptext_string",
    },
    {
        .name = "add_usage_text",
        .handler = handle_help_add_command,
        .mode = COMMAND_ANY,
        .help = "Add new command usage text; "
            "command can be multiple tokens.",
        .usage = "command_name usage_string",
    },
    {
        .name = "sleep",
        .handler = handle_sleep_command,
        .mode = COMMAND_ANY,
        .help = "Sleep for specified number of milliseconds.  "
            "\"busy\" will busy wait instead (avoid this).",
        .usage = "milliseconds ['busy']",
    },
    {
        .name = "help",
        .handler = handle_help_command,
        .mode = COMMAND_ANY,
        .help = "Show full command help; "
            "command can be multiple tokens.",
        .usage = "[command_name]",
    },
    {
        .name = "usage",
        .handler = handle_help_command,
        .mode = COMMAND_ANY,
        .help = "Show basic command usage; "
            "command can be multiple tokens.",
        .usage = "[command_name]",
    },
    {
        .name = "command",
        .mode = COMMAND_ANY,
        .help = "core command group (introspection)",
        .chain = command_subcommand_handlers,
        .usage = "",
    },
    COMMAND_REGISTRATION_DONE
};
 
struct command_context *command_init(const char *startup_tcl, Jim_Interp *interp)
{
    struct command_context *context = calloc(1, sizeof(struct command_context));
 
    context->mode = COMMAND_EXEC;
 
    /* context can be duplicated. Put list head on separate mem-chunk to keep list consistent */
    context->help_list = malloc(sizeof(*context->help_list));
    INIT_LIST_HEAD(context->help_list);
 
    /* Create a jim interpreter if we were not handed one */
    if (!interp) {
        /* Create an interpreter */
        interp = Jim_CreateInterp();
        /* Add all the Jim core commands */
        Jim_RegisterCoreCommands(interp);
        Jim_InitStaticExtensions(interp);
    }
 
    context->interp = interp;
 
    register_commands(context, NULL, command_builtin_handlers);
 
    Jim_SetAssocData(interp, "context", NULL, context);
    if (Jim_Eval_Named(interp, startup_tcl, "embedded:startup.tcl", 1) == JIM_ERR) {
        LOG_ERROR("Failed to run startup.tcl (embedded into OpenOCD)");
        Jim_MakeErrorMessage(interp);
        LOG_USER_N("%s", Jim_GetString(Jim_GetResult(interp), NULL));
        exit(-1);
    }
    Jim_DeleteAssocData(interp, "context");
 
    return context;
}
 
void command_exit(struct command_context *context)
{
    if (!context)
        return;
 
    Jim_FreeInterp(context->interp);
    free(context->help_list);
    command_done(context);
}
 
int command_context_mode(struct command_context *cmd_ctx, enum command_mode mode)
{
    if (!cmd_ctx)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    cmd_ctx->mode = mode;
    return ERROR_OK;
}
 
void process_jim_events(struct command_context *cmd_ctx)
{
    static int recursion;
    if (recursion)
        return;
 
    recursion++;
    Jim_ProcessEvents(cmd_ctx->interp, JIM_ALL_EVENTS | JIM_DONT_WAIT);
    recursion--;
}
 
#define DEFINE_PARSE_NUM_TYPE(name, type, func, min, max) \
    int parse ## name(const char *str, type * ul) \
    { \
        if (!*str) { \
            LOG_ERROR("Invalid command argument"); \
            return ERROR_COMMAND_ARGUMENT_INVALID; \
        } \
        char *end; \
        errno = 0; \
        *ul = func(str, &end, 0); \
        if (*end) { \
            LOG_ERROR("Invalid command argument"); \
            return ERROR_COMMAND_ARGUMENT_INVALID; \
        } \
        if ((max == *ul) && (errno == ERANGE)) { \
            LOG_ERROR("Argument overflow"); \
            return ERROR_COMMAND_ARGUMENT_OVERFLOW; \
        } \
        if (min && (min == *ul) && (errno == ERANGE)) { \
            LOG_ERROR("Argument underflow"); \
            return ERROR_COMMAND_ARGUMENT_UNDERFLOW; \
        } \
        return ERROR_OK; \
    }
DEFINE_PARSE_NUM_TYPE(_ulong, unsigned long, strtoul, 0, ULONG_MAX)
DEFINE_PARSE_NUM_TYPE(_ullong, unsigned long long, strtoull, 0, ULLONG_MAX)
DEFINE_PARSE_NUM_TYPE(_long, long, strtol, LONG_MIN, LONG_MAX)
DEFINE_PARSE_NUM_TYPE(_llong, long long, strtoll, LLONG_MIN, LLONG_MAX)
 
#define DEFINE_PARSE_WRAPPER(name, type, min, max, functype, funcname) \
    int parse ## name(const char *str, type * ul) \
    { \
        functype n; \
        int retval = parse ## funcname(str, &n); \
        if (retval != ERROR_OK) \
            return retval; \
        if (n > max) \
            return ERROR_COMMAND_ARGUMENT_OVERFLOW; \
        if (min) \
            return ERROR_COMMAND_ARGUMENT_UNDERFLOW; \
        *ul = n; \
        return ERROR_OK; \
    }
 
#define DEFINE_PARSE_ULONGLONG(name, type, min, max) \
    DEFINE_PARSE_WRAPPER(name, type, min, max, unsigned long long, _ullong)
DEFINE_PARSE_ULONGLONG(_uint, unsigned int, 0, UINT_MAX)
DEFINE_PARSE_ULONGLONG(_u64,  uint64_t, 0, UINT64_MAX)
DEFINE_PARSE_ULONGLONG(_u32,  uint32_t, 0, UINT32_MAX)
DEFINE_PARSE_ULONGLONG(_u16,  uint16_t, 0, UINT16_MAX)
DEFINE_PARSE_ULONGLONG(_u8,   uint8_t,  0, UINT8_MAX)
 
DEFINE_PARSE_ULONGLONG(_target_addr, target_addr_t, 0, TARGET_ADDR_MAX)
 
#define DEFINE_PARSE_LONGLONG(name, type, min, max) \
    DEFINE_PARSE_WRAPPER(name, type, min, max, long long, _llong)
DEFINE_PARSE_LONGLONG(_int, int,     n < INT_MIN,   INT_MAX)
DEFINE_PARSE_LONGLONG(_s64, int64_t, n < INT64_MIN, INT64_MAX)
DEFINE_PARSE_LONGLONG(_s32, int32_t, n < INT32_MIN, INT32_MAX)
DEFINE_PARSE_LONGLONG(_s16, int16_t, n < INT16_MIN, INT16_MAX)
DEFINE_PARSE_LONGLONG(_s8,  int8_t,  n < INT8_MIN,  INT8_MAX)
 
static int command_parse_bool(const char *in, bool *out,
    const char *on, const char *off)
{
    if (strcasecmp(in, on) == 0)
        *out = true;
    else if (strcasecmp(in, off) == 0)
        *out = false;
    else
        return ERROR_COMMAND_SYNTAX_ERROR;
    return ERROR_OK;
}
 
int command_parse_bool_arg(const char *in, bool *out)
{
    if (command_parse_bool(in, out, "on", "off") == ERROR_OK)
        return ERROR_OK;
    if (command_parse_bool(in, out, "enable", "disable") == ERROR_OK)
        return ERROR_OK;
    if (command_parse_bool(in, out, "true", "false") == ERROR_OK)
        return ERROR_OK;
    if (command_parse_bool(in, out, "yes", "no") == ERROR_OK)
        return ERROR_OK;
    if (command_parse_bool(in, out, "1", "0") == ERROR_OK)
        return ERROR_OK;
    return ERROR_COMMAND_SYNTAX_ERROR;
}
 
COMMAND_HELPER(command_parse_str_to_buf, const char *str, void *buf, unsigned int buf_len)
{
    assert(str);
    assert(buf);
 
    int ret = str_to_buf(str, buf, buf_len);
    if (ret == ERROR_OK)
        return ret;
 
    /* Provide a clear error message to the user */
    if (ret == ERROR_INVALID_NUMBER) {
        command_print(CMD, "'%s' is not a valid number", str);
    } else if (ret == ERROR_NUMBER_EXCEEDS_BUFFER) {
        command_print(CMD, "Number %s exceeds %u bits", str, buf_len);
    } else {
        command_print(CMD, "Could not parse number '%s'", str);
    }
 
    return ERROR_COMMAND_ARGUMENT_INVALID;
}
 
COMMAND_HELPER(handle_command_parse_bool, bool *out, const char *label)
{
    switch (CMD_ARGC) {
        case 1: {
            const char *in = CMD_ARGV[0];
            if (command_parse_bool_arg(in, out) != ERROR_OK) {
                LOG_ERROR("%s: argument '%s' is not valid", CMD_NAME, in);
                return ERROR_COMMAND_SYNTAX_ERROR;
            }
        }
            /* fallthrough */
        case 0:
            LOG_INFO("%s is %s", label, *out ? "enabled" : "disabled");
            break;
        default:
            return ERROR_COMMAND_SYNTAX_ERROR;
    }
    return ERROR_OK;
}