- fix illegal memory access in unregister_command function

[openocd.git] / src / helper / command.c

/***************************************************************************
 *   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)                      *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "replacements.h"
#include "target.h"
#include "command.h"
#include "configuration.h"

#include "log.h"
#include "time_support.h"
#include "jim-eventloop.h"

#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>

int fast_and_dangerous = 0;
Jim_Interp *interp = NULL;

int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
int handle_fast_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);

int run_command(command_context_t *context, command_t *c, char *words[], int num_words);

static void tcl_output(void *privData, const char *file, int line, const char *function, const char *string)
{
        Jim_Obj *tclOutput=(Jim_Obj *)privData;

        Jim_AppendString(interp, tclOutput, string, strlen(string));
}

extern command_context_t *global_cmd_ctx;

static int script_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
        /* the private data is stashed in the interp structure */
        command_t *c;
        command_context_t *context;
        int retval;
        int i;
        int nwords;
        char **words;

        /* DANGER!!!! be careful what we invoke here, since interp->cmdPrivData might
         * get overwritten by running other Jim commands! Treat it as an
         * emphemeral global variable that is used in lieu of an argument
         * to the fn and fish it out manually.
         */
        c = interp->cmdPrivData;
        if (c==NULL)
        {
                LOG_ERROR("BUG: interp->cmdPrivData==NULL");
                return JIM_ERR;
        }
        target_call_timer_callbacks_now();
        LOG_USER_N("%s", ""); /* Keep GDB connection alive*/

        LOG_DEBUG("script_command - %s", c->name);

        words = malloc(sizeof(char *) * argc);
        for (i = 0; i < argc; i++)
        {
                int len;
                const char *w=Jim_GetString(argv[i], &len);
                if (*w=='#')
                {
                        /* hit an end of line comment */
                        break;
                }
                words[i] = strdup(w);
                if (words[i] == NULL)
                {
                        return JIM_ERR;
                }
                LOG_DEBUG("script_command - %s, argv[%u]=%s", c->name, i, words[i]);
        }
        nwords = i;

        /* grab the command context from the associated data */
        context = Jim_GetAssocData(interp, "context");
        if (context == NULL)
        {
                /* Tcl can invoke commands directly instead of via command_run_line(). This would
                 * happen when the Jim Tcl interpreter is provided by eCos.
                 */
                context = global_cmd_ctx;
        }

        /* capture log output and return it */
        Jim_Obj *tclOutput = Jim_NewStringObj(interp, "", 0);
        /* a garbage collect can happen, so we need a reference count to this object */
        Jim_IncrRefCount(tclOutput);

        log_add_callback(tcl_output, tclOutput);

        retval = run_command(context, c, words, nwords);

        log_remove_callback(tcl_output, tclOutput);

        /* We dump output into this local variable */
        Jim_SetResult(interp, tclOutput);
        Jim_DecrRefCount(interp, tclOutput);

        for (i = 0; i < nwords; i++)
                free(words[i]);
        free(words);

        int *return_retval = Jim_GetAssocData(interp, "retval");
        if (return_retval != NULL)
        {
                *return_retval = retval;
        }

        return (retval==ERROR_OK)?JIM_OK:JIM_ERR;
}

/* nice short description of source file */
#define __THIS__FILE__ "command.c"

command_t* register_command(command_context_t *context, command_t *parent, char *name, int (*handler)(struct command_context_s *context, char* name, char** args, int argc), enum command_mode mode, char *help)
{
        command_t *c, *p;

        if (!context || !name)
                return NULL;

        c = malloc(sizeof(command_t));

        c->name = strdup(name);
        c->parent = parent;
        c->children = NULL;
        c->handler = handler;
        c->mode = mode;
        if (!help)
                help="";
        c->next = NULL;

        /* place command in tree */
        if (parent)
        {
                if (parent->children)
                {
                        /* find last child */
                        for (p = parent->children; p && p->next; p = p->next);
                        if (p)
                                p->next = c;
                }
                else
                {
                        parent->children = c;
                }
        }
        else
        {
                if (context->commands)
                {
                        /* find last command */
                        for (p = context->commands; p && p->next; p = p->next);
                        if (p)
                                p->next = c;
                }
                else
                {
                        context->commands = c;
                }
        }

        /* just a placeholder, no handler */
        if (c->handler==NULL)
                return c;

        /* If this is a two level command, e.g. "flash banks", then the
         * "unknown" proc in startup.tcl must redirect to  this command.
         *
         * "flash banks" is translated by "unknown" to "flash_banks"
         * if such a proc exists
         */
        /* Print help for command */
        const char *t1="";
        const char *t2="";
        const char *t3="";
        /* maximum of two levels :-) */
        if (c->parent!=NULL)
        {
                t1=c->parent->name;
                t2="_";
        }
        t3=c->name;
        const char *full_name=alloc_printf("ocd_%s%s%s", t1, t2, t3);
        Jim_CreateCommand(interp, full_name, script_command, c, NULL);
        free((void *)full_name);

        /* we now need to add an overrideable proc */
        const char *override_name=alloc_printf("proc %s%s%s {args} {if {[catch {eval \"ocd_%s%s%s $args\"}]==0} {return \"\"} else { return -code error }", t1, t2, t3, t1, t2, t3);
        Jim_Eval_Named(interp, override_name, __THIS__FILE__, __LINE__ );
        free((void *)override_name);

        /* accumulate help text in Tcl helptext list.  */
    Jim_Obj *helptext=Jim_GetGlobalVariableStr(interp, "ocd_helptext", JIM_ERRMSG);
    if (Jim_IsShared(helptext))
        helptext = Jim_DuplicateObj(interp, helptext);
        Jim_Obj *cmd_entry=Jim_NewListObj(interp, NULL, 0);

        Jim_Obj *cmd_list=Jim_NewListObj(interp, NULL, 0);

        /* maximum of two levels :-) */
        if (c->parent!=NULL)
        {
                Jim_ListAppendElement(interp, cmd_list, Jim_NewStringObj(interp, c->parent->name, -1));
        }
        Jim_ListAppendElement(interp, cmd_list, Jim_NewStringObj(interp, c->name, -1));

        Jim_ListAppendElement(interp, cmd_entry, cmd_list);
        Jim_ListAppendElement(interp, cmd_entry, Jim_NewStringObj(interp, help, -1));
        Jim_ListAppendElement(interp, helptext, cmd_entry);
        return c;
}

int unregister_all_commands(command_context_t *context)
{
        command_t *c, *c2;

        if (context == NULL)
                return ERROR_OK;

        while(NULL != context->commands)
        {
                c = context->commands;

                while(NULL != c->children)
                {
                        c2 = c->children;
                        c->children = c->children->next;
                        free(c2->name);
                        c2->name = NULL;
                        free(c2);
                        c2 = NULL;
                }

                context->commands = context->commands->next;

                free(c->name);
                c->name = NULL;
                free(c);
                c = NULL;
        }

        return ERROR_OK;
}

int unregister_command(command_context_t *context, char *name)
{
        command_t *c, *p = NULL, *c2;

        if ((!context) || (!name))
                return ERROR_INVALID_ARGUMENTS;

        /* find command */
        c = context->commands;
        
        while(NULL != c)
        {               
                if (strcmp(name, c->name) == 0)
                {
                        /* unlink command */
                        if (p)
                        {
                                p->next = c->next;
                        }
                        else
                        {
                                /* first element in command list */
                                context->commands = c->next;
                        }
                        
                        /* unregister children */
                        while(NULL != c->children)
                        {
                                c2 = c->children;
                                c->children = c->children->next;
                                free(c2->name);
                                c2->name = NULL;
                                free(c2);
                                c2 = NULL;
                        }
                        
                        /* delete command */
                        free(c->name);
                        c->name = NULL;
                        free(c);
                        c = NULL;
                        return ERROR_OK;
                }
                
                /* remember the last command for unlinking */
                p = c;
                c = c->next;
        }

        return ERROR_OK;
}

void command_output_text(command_context_t *context, const char *data)
{
        if( context && context->output_handler && data  ){
                context->output_handler( context, data );
        }
}

void command_print_n(command_context_t *context, char *format, ...)
{
        char *string;

        va_list ap;
        va_start(ap, format);

        string = alloc_vprintf(format, ap);
        if (string != NULL)
        {
                /* 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.
                 */
                LOG_USER_N("%s", string);
                // We already printed it above
                //command_output_text(context, string);
                free(string);
        }

        va_end(ap);
}

void command_print(command_context_t *context, char *format, ...)
{
        char *string;

        va_list ap;
        va_start(ap, format);

        string = alloc_vprintf(format, ap);
        if (string != NULL)
        {
                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.
                 */
                LOG_USER_N("%s", string);
                // We already printed it above
                //command_output_text(context, string);
                free(string);
        }

        va_end(ap);
}

int run_command(command_context_t *context, command_t *c, char *words[], int num_words)
{
        int start_word=0;
        if (!((context->mode == COMMAND_CONFIG) || (c->mode == COMMAND_ANY) || (c->mode == context->mode) ))
        {
                /* Config commands can not run after the config stage */
                LOG_ERROR("Illegal mode for command");
                return ERROR_FAIL;
        }

        int retval = c->handler(context, c->name, words + start_word + 1, num_words - start_word - 1);
        if (retval == ERROR_COMMAND_SYNTAX_ERROR)
        {
                /* Print help for command */
                const char *t1="";
                const char *t2="";
                const char *t3="";
                /* maximum of two levels :-) */
                if (c->parent!=NULL)
                {
                        t1=c->parent->name;
                        t2=" ";
                }
                t3=c->name;
                command_run_linef(context, "help {%s%s%s}", t1, t2, t3);
        }
        else if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
        {
                /* just fall through for a shutdown request */
        }
        else if (retval != ERROR_OK)
        {
                /* we do not print out an error message because the command *should*
                 * have printed out an error
                 */
                LOG_DEBUG("Command failed with error code %d", retval);
        }

        return retval;
}

int command_run_line(command_context_t *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 retval=ERROR_FAIL;
        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.
         */
        Jim_DeleteAssocData(interp, "context");
        retcode = Jim_SetAssocData(interp, "context", NULL, context);
        if (retcode == JIM_OK)
        {
                /* associated the return value */
                Jim_DeleteAssocData(interp, "retval");
                retcode = Jim_SetAssocData(interp, "retval", NULL, &retval);
                if (retcode == JIM_OK)
                {
                        retcode = Jim_Eval_Named(interp, line, __THIS__FILE__, __LINE__ );

                        Jim_DeleteAssocData(interp, "retval");
                }
                Jim_DeleteAssocData(interp, "context");
        }
        if (retcode == JIM_ERR) {
                if (retval!=ERROR_COMMAND_CLOSE_CONNECTION)
                {
                        /* We do not print the connection closed error message */
                        Jim_PrintErrorMessage(interp);
                }
                if (retval==ERROR_OK)
                {
                        /* It wasn't a low level OpenOCD command that failed */
                        return ERROR_FAIL;
                }
                return retval;
        } else if (retcode == JIM_EXIT) {
                /* ignore. */
                /* exit(Jim_GetExitCode(interp)); */
        } else {
                const char *result;
                int reslen;

                result = Jim_GetString(Jim_GetResult(interp), &reslen);
                if (reslen) {
                        int i;
                        char buff[256+1];
                        for (i = 0; i < reslen; i += 256)
                        {
                                int chunk;
                                chunk = reslen - i;
                                if (chunk > 256)
                                        chunk = 256;
                                strncpy(buff, result+i, chunk);
                                buff[chunk] = 0;
                                LOG_USER_N("%s", buff);
                        }
                        LOG_USER_N("%s", "\n");
                }
        }
        return retval;
}

int command_run_linef(command_context_t *context, char *format, ...)
{
        int retval=ERROR_FAIL;
        char *string;
        va_list ap;
        va_start(ap, format);
        string = alloc_vprintf(format, ap);
        if (string!=NULL)
        {
                retval=command_run_line(context, string);
        }
        va_end(ap);
        return retval;
}

void command_set_output_handler(command_context_t* context, int (*output_handler)(struct command_context_s *context, const char* line), void *priv)
{
        context->output_handler = output_handler;
        context->output_handler_priv = priv;
}

command_context_t* copy_command_context(command_context_t* context)
{
        command_context_t* copy_context = malloc(sizeof(command_context_t));

        *copy_context = *context;

        return copy_context;
}

int command_done(command_context_t *context)
{
        free(context);
        context = NULL;

        return ERROR_OK;
}

/* find full path to file */
static int jim_find(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
        if (argc != 2)
                return JIM_ERR;
        const char *file = Jim_GetString(argv[1], NULL);
        char *full_path = find_file(file);
        if (full_path == NULL)
                return JIM_ERR;
        Jim_Obj *result = Jim_NewStringObj(interp, full_path, strlen(full_path));
        free(full_path);

        Jim_SetResult(interp, result);
        return JIM_OK;
}

static int jim_echo(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
        if (argc != 2)
                return JIM_ERR;
        const char *str = Jim_GetString(argv[1], NULL);
        LOG_USER("%s", str);
        return JIM_OK;
}

static size_t openocd_jim_fwrite(const void *_ptr, size_t size, size_t n, void *cookie)
{
        size_t nbytes;
        const char *ptr;
        Jim_Interp *interp;

        /* make it a char easier to read code */
        ptr = _ptr;
        interp = cookie;
        nbytes = size * n;
        if (ptr == NULL || interp == NULL || nbytes == 0) {
                return 0;
        }

        /* do we have to chunk it? */
        if (ptr[nbytes] == 0)
        {
                /* no it is a C style string */
                LOG_USER_N("%s", ptr);
                return strlen(ptr);
        }
        /* GRR we must chunk - not null terminated */
        while (nbytes) {
                char chunk[128+1];
                int x;

                x = nbytes;
                if (x > 128) {
                        x = 128;
                }
                /* copy it */
                memcpy(chunk, ptr, x);
                /* terminate it */
                chunk[n] = 0;
                /* output it */
                LOG_USER_N("%s", chunk);
                ptr += x;
                nbytes -= x;
        }

        return n;
}

static size_t openocd_jim_fread(void *ptr, size_t size, size_t n, void *cookie)
{
        /* TCL wants to read... tell him no */
        return 0;
}

static int openocd_jim_vfprintf(void *cookie, const char *fmt, va_list ap)
{
        char *cp;
        int n;
        Jim_Interp *interp;

        n = -1;
        interp = cookie;
        if (interp == NULL)
                return n;

        cp = alloc_vprintf(fmt, ap);
        if (cp)
        {
                LOG_USER_N("%s", cp);
                n = strlen(cp);
                free(cp);
        }
        return n;
}

static int openocd_jim_fflush(void *cookie)
{
        /* nothing to flush */
        return 0;
}

static char* openocd_jim_fgets(char *s, int size, void *cookie)
{
        /* not supported */
        errno = ENOTSUP;
        return NULL;
}


static int jim_capture(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
        if (argc != 2)
                return JIM_ERR;
        int retcode;
        const char *str = Jim_GetString(argv[1], NULL);

        /* capture log output and return it */
        Jim_Obj *tclOutput = Jim_NewStringObj(interp, "", 0);
        /* a garbage collect can happen, so we need a reference count to this object */
        Jim_IncrRefCount(tclOutput);

        log_add_callback(tcl_output, tclOutput);

        retcode = Jim_Eval_Named(interp, str, __THIS__FILE__, __LINE__ );

        log_remove_callback(tcl_output, tclOutput);

        /* We dump output into this local variable */
        Jim_SetResult(interp, tclOutput);
        Jim_DecrRefCount(interp, tclOutput);

        return retcode;
}

command_context_t* command_init()
{
        command_context_t* context = malloc(sizeof(command_context_t));
        extern const char startup_tcl[];

        context->mode = COMMAND_EXEC;
        context->commands = NULL;
        context->current_target = 0;
        context->output_handler = NULL;
        context->output_handler_priv = NULL;

#ifdef JIM_EMBEDDED
        Jim_InitEmbedded();
        /* Create an interpreter */
        interp = Jim_CreateInterp();
        /* Add all the Jim core commands */
        Jim_RegisterCoreCommands(interp);
#endif

        Jim_CreateCommand(interp, "ocd_find", jim_find, NULL, NULL);
        Jim_CreateCommand(interp, "echo", jim_echo, NULL, NULL);
        Jim_CreateCommand(interp, "capture", jim_capture, NULL, NULL);

        /* Set Jim's STDIO */
        interp->cookie_stdin = interp;
        interp->cookie_stdout = interp;
        interp->cookie_stderr = interp;
        interp->cb_fwrite = openocd_jim_fwrite;
        interp->cb_fread = openocd_jim_fread ;
        interp->cb_vfprintf = openocd_jim_vfprintf;
        interp->cb_fflush = openocd_jim_fflush;
        interp->cb_fgets = openocd_jim_fgets;

        add_default_dirs();

#ifdef JIM_EMBEDDED
        Jim_EventLoopOnLoad(interp);
#endif
        if (Jim_Eval_Named(interp, startup_tcl, "embedded:startup.tcl",1)==JIM_ERR)
        {
                LOG_ERROR("Failed to run startup.tcl (embedded into OpenOCD compile time)");
                Jim_PrintErrorMessage(interp);
                exit(-1);
        }

        register_command(context, NULL, "sleep", handle_sleep_command,
                                         COMMAND_ANY, "<n> [busy] - sleep for n milliseconds. \"busy\" means busy wait");

        register_command(context, NULL, "fast", handle_fast_command,
                                         COMMAND_ANY, "fast <enable/disable> - place at beginning of config files. Sets defaults to fast and dangerous.");

        return context;
}

int command_context_mode(command_context_t *cmd_ctx, enum command_mode mode)
{
        if (!cmd_ctx)
                return ERROR_INVALID_ARGUMENTS;

        cmd_ctx->mode = mode;
        return ERROR_OK;
}

/* sleep command sleeps for <n> miliseconds
 * this is useful in target startup scripts
 */
int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        unsigned long duration = 0;
        int busy = 0;

        if (argc==1)
        {

        } else if (argc==2)
        {
                if (strcmp(args[1], "busy")!=0)
                        return ERROR_COMMAND_SYNTAX_ERROR;
                busy = 1;
        } else
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }

        duration = strtoul(args[0], NULL, 0);

        if (busy)
        {
                busy_sleep(duration);
        } else
        {
                long long then=timeval_ms();
                while ((timeval_ms()-then)<duration)
                {
                        target_call_timer_callbacks_now();
                        usleep(1000);
                }
        }

        return ERROR_OK;
}

int handle_fast_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc!=1)
                return ERROR_COMMAND_SYNTAX_ERROR;

        fast_and_dangerous = strcmp("enable", args[0])==0;

        return ERROR_OK;
}

void process_jim_events(void)
{
#ifdef JIM_EMBEDDED
        static int recursion = 0;

        if (!recursion)
        {
                recursion++;
                Jim_ProcessEvents (interp, JIM_ALL_EVENTS|JIM_DONT_WAIT);
                recursion--;
        }
#endif
}

void register_jim(struct command_context_s *cmd_ctx, const char *name, int (*cmd)(Jim_Interp *interp, int argc, Jim_Obj *const *argv), const char *help)
{
        Jim_CreateCommand(interp, name, cmd, NULL, NULL);

        /* FIX!!! it would be prettier to invoke add_help_text...
           accumulate help text in Tcl helptext list.  */
        Jim_Obj *helptext=Jim_GetGlobalVariableStr(interp, "ocd_helptext", JIM_ERRMSG);
        if (Jim_IsShared(helptext))
                helptext = Jim_DuplicateObj(interp, helptext);

        Jim_Obj *cmd_entry=Jim_NewListObj(interp, NULL, 0);

        Jim_Obj *cmd_list=Jim_NewListObj(interp, NULL, 0);
        Jim_ListAppendElement(interp, cmd_list, Jim_NewStringObj(interp, name, -1));

        Jim_ListAppendElement(interp, cmd_entry, cmd_list);
        Jim_ListAppendElement(interp, cmd_entry, Jim_NewStringObj(interp, help, -1));
        Jim_ListAppendElement(interp, helptext, cmd_entry);
}


/* return global variable long value or 0 upon failure */
long jim_global_long(const char *variable)
{
        Jim_Obj *objPtr=Jim_GetGlobalVariableStr(interp, variable, JIM_ERRMSG);
        long t;
        if (Jim_GetLong(interp, objPtr, &t)==JIM_OK)
        {
                return t;
        }
        return 0;
}