/*
*
* Shell Command Set Management
*
* Author:
* WORK: fernando.ruiz@ctv.es
* HOME: correo@fernando-ruiz.com
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <time.h>
#include <termios.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <rtems.h>
#include <rtems/shell.h>
#include <rtems/shellconfig.h>
#include <rtems/libio_.h>
#include "internal.h"
/*
* Common linked list of shell commands.
*
* Because the help report is very long, there is a topic for each command.
*
* Help list the topics
* help [topic] list the commands for the topic
* help [command] help for the command
*
*/
rtems_shell_cmd_t * rtems_shell_first_cmd;
rtems_shell_topic_t * rtems_shell_first_topic;
/*
* Find the topic from the set of topics registered.
*/
rtems_shell_topic_t * rtems_shell_lookup_topic(const char * topic) {
rtems_shell_topic_t * shell_topic;
shell_topic=rtems_shell_first_topic;
while (shell_topic) {
if (!strcmp(shell_topic->topic,topic))
return shell_topic;
shell_topic=shell_topic->next;
}
return NULL;
}
/*
* Add a new topic to the list of topics
*/
static rtems_shell_topic_t * rtems_shell_add_topic(const char * topic) {
rtems_shell_topic_t * current,*aux;
if (!rtems_shell_first_topic) {
aux = malloc(sizeof(rtems_shell_topic_t));
aux->topic = topic;
aux->next = NULL;
return rtems_shell_first_topic = aux;
}
current=rtems_shell_first_topic;
if (!strcmp(topic,current->topic))
return current;
while (current->next) {
if (!strcmp(topic,current->next->topic))
return current->next;
current=current->next;
}
aux = malloc(sizeof(rtems_shell_topic_t));
aux->topic = topic;
aux->next = NULL;
current->next = aux;
return aux;
}
/*
* Find the command in the set
*/
rtems_shell_cmd_t * rtems_shell_lookup_cmd(const char * cmd) {
rtems_shell_cmd_t * shell_cmd;
shell_cmd=rtems_shell_first_cmd;
while (shell_cmd) {
if (!strcmp(shell_cmd->name,cmd)) return shell_cmd;
shell_cmd=shell_cmd->next;
};
return NULL;
}
/*
* Add a command structure to the set of known commands
*/
rtems_shell_cmd_t *rtems_shell_add_cmd_struct(
rtems_shell_cmd_t *shell_cmd
)
{
rtems_shell_cmd_t **next_ptr = &rtems_shell_first_cmd;
rtems_shell_cmd_t *existing;
/*
* Iterate through all commands and check if a command with this name is
* already present.
*/
while ((existing = *next_ptr) != NULL) {
if (strcmp(existing->name, shell_cmd->name) == 0)
return NULL;
next_ptr = &existing->next;
}
/* Ensure that the user can read and execute commands */
shell_cmd->mode |= S_IRUSR | S_IXUSR;
/* Append */
*next_ptr = shell_cmd;
rtems_shell_add_topic( shell_cmd->topic );
return shell_cmd;
}
/*
* Add a command as a set of arguments to the set and
* allocate the command structure on the fly.
*/
rtems_shell_cmd_t * rtems_shell_add_cmd(
const char *name,
const char *topic,
const char *usage,
rtems_shell_command_t command
)
{
rtems_shell_cmd_t *shell_cmd = NULL;
char *my_name = NULL;
char *my_topic = NULL;
char *my_usage = NULL;
/* Reject empty commands */
if (name == NULL || command == NULL) {
return NULL;
}
/* Allocate command stucture */
shell_cmd = (rtems_shell_cmd_t *) calloc(1, sizeof(*shell_cmd));
if (shell_cmd == NULL) {
return NULL;
}
/* Allocate strings */
my_name = strdup(name);
my_topic = strdup(topic);
my_usage = strdup(usage);
/* Assign values */
shell_cmd->name = my_name;
shell_cmd->topic = my_topic;
shell_cmd->usage = my_usage;
shell_cmd->command = command;
if (rtems_shell_add_cmd_struct(shell_cmd) == NULL) {
/* Something is wrong, free allocated resources */
free(my_usage);
free(my_topic);
free(my_name);
free(shell_cmd);
return NULL;
}
return shell_cmd;
}
/* ----------------------------------------------- *
* you can make an alias for every command.
* ----------------------------------------------- */
rtems_shell_cmd_t *rtems_shell_alias_cmd(
const char *cmd,
const char *alias
)
{
rtems_shell_cmd_t *shell_cmd, *shell_aux;
shell_aux = (rtems_shell_cmd_t *) NULL;
if (alias) {
shell_aux = rtems_shell_lookup_cmd(alias);
if (shell_aux != NULL) {
return NULL;
}
shell_cmd = rtems_shell_lookup_cmd(cmd);
if (shell_cmd != NULL) {
shell_aux = rtems_shell_add_cmd(
alias,
shell_cmd->topic,
shell_cmd->usage,
shell_cmd->command
);
if (shell_aux) {
shell_aux->alias = shell_cmd;
shell_aux->mode = shell_cmd->mode;
shell_aux->uid = shell_cmd->uid;
shell_aux->gid = shell_cmd->gid;
}
}
}
return shell_aux;
}
bool rtems_shell_can_see_cmd(const rtems_shell_cmd_t *shell_cmd)
{
return rtems_filesystem_check_access(
RTEMS_FS_PERMS_READ,
shell_cmd->mode,
shell_cmd->uid,
shell_cmd->gid
);
}
static bool rtems_shell_can_execute_cmd(const rtems_shell_cmd_t *shell_cmd)
{
return rtems_filesystem_check_access(
RTEMS_FS_PERMS_EXEC,
shell_cmd->mode,
shell_cmd->uid,
shell_cmd->gid
);
}
int rtems_shell_execute_cmd(const char *cmd, int argc, char *argv[])
{
rtems_shell_cmd_t *shell_cmd;
if (argv[0] == NULL) {
return -1;
}
shell_cmd = rtems_shell_lookup_cmd(argv[0]);
if (shell_cmd != NULL && !rtems_shell_can_see_cmd(shell_cmd)) {
shell_cmd = NULL;
}
if (shell_cmd == NULL) {
return rtems_shell_script_file(argc, argv);
} else if (rtems_shell_can_execute_cmd(shell_cmd)) {
return shell_cmd->command(argc, argv);
} else {
fprintf(stderr, "%s: Permission denied\n", cmd);
return -1;
}
}