/*
* Copyright (C) 2005 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <main/kconsole.h>
#include <console/console.h>
#include <console/chardev.h>
#include <print.h>
#include <panic.h>
#include <typedefs.h>
#include <arch/types.h>
#include <list.h>
#include <arch.h>
#include <func.h>
#include <macros.h>
#define MAX_CMDLINE 256
/** Simple kernel console.
*
* The console is realized by kernel thread kconsole.
* It doesn't understand any commands on its own, but
* makes it possible for other kernel subsystems to
* register their own commands.
*/
/** Locking.
*
* There is a list of cmd_info_t structures. This list
* is protected by cmd_lock spinlock. Note that specially
* the link elements of cmd_info_t are protected by
* this lock.
*
* Each cmd_info_t also has its own lock, which protects
* all elements thereof except the link element.
*
* cmd_lock must be acquired before any cmd_info lock.
* When locking two cmd info structures, structure with
* lower address must be locked first.
*/
spinlock_t cmd_lock; /**< Lock protecting command list. */
link_t cmd_head; /**< Command list. */
static cmd_info_t *parse_cmdline(char *cmdline, size_t len);
static int cmd_help(cmd_arg_t *cmd);
static cmd_info_t help_info;
/** Initialize kconsole data structures. */
void kconsole_init(void)
{
spinlock_initialize(&cmd_lock);
list_initialize(&cmd_head);
help_info.name = "help";
help_info.description = "List supported commands.";
help_info.func = cmd_help;
help_info.argc = 0;
help_info.argv = NULL;
spinlock_initialize(&help_info.lock);
link_initialize(&help_info.link);
if (!cmd_register(&help_info))
panic("could not register command\n");
}
/** Register kconsole command.
*
* @param cmd Structure describing the command.
*
* @return 0 on failure, 1 on success.
*/
int cmd_register(cmd_info_t *cmd)
{
ipl_t ipl;
link_t *cur;
ipl = interrupts_disable();
spinlock_lock(&cmd_lock);
/*
* Make sure the command is not already listed.
*/
for (cur = cmd_head.next; cur != &cmd_head; cur = cur->next) {
cmd_info_t *hlp;
hlp = list_get_instance(cur, cmd_info_t, link);
if (hlp == cmd) {
/* The command is already there. */
spinlock_unlock(&cmd_lock);
interrupts_restore(ipl);
return 0;
}
/* Avoid deadlock. */
if (hlp < cmd) {
spinlock_lock(&hlp->lock);
spinlock_lock(&cmd->lock);
} else {
spinlock_lock(&cmd->lock);
spinlock_lock(&hlp->lock);
}
if ((strcmp(hlp
->name
, cmd
->name
, strlen(cmd
->name
)) == 0)) { /* The command is already there. */
spinlock_unlock(&hlp->lock);
spinlock_unlock(&cmd->lock);
spinlock_unlock(&cmd_lock);
interrupts_restore(ipl);
return 0;
}
spinlock_unlock(&hlp->lock);
spinlock_unlock(&cmd->lock);
}
/*
* Now the command can be added.
*/
list_append(&cmd->link, &cmd_head);
spinlock_unlock(&cmd_lock);
interrupts_restore(ipl);
return 1;
}
/** Kernel console managing thread.
*
* @param arg Not used.
*/
void kconsole(void *arg)
{
char cmdline[MAX_CMDLINE+1];
cmd_info_t *cmd_info;
count_t len;
if (!stdin) {
printf("%s: no stdin\n", __FUNCTION__
); return;
}
while (true) {
len
= gets(stdin
, cmdline
, sizeof(cmdline
)); cmdline[len] = '\0';
cmd_info = parse_cmdline(cmdline, len);
if (!cmd_info) {
continue;
}
(void) cmd_info->func(cmd_info->argv);
}
}
/** Parse command line.
*
* @param cmdline Command line as read from input device.
* @param len Command line length.
*
* @return Structure describing the command.
*/
cmd_info_t *parse_cmdline(char *cmdline, size_t len)
{
index_t start = 0, end = 0;
bool found_start = false;
cmd_info_t *cmd = NULL;
link_t *cur;
ipl_t ipl;
int i;
for (i = 0; i < len; i++) {
if (!found_start) {
if (is_white(cmdline[i]))
start++;
else
found_start = true;
} else {
if (is_white(cmdline[i]))
break;
}
}
end = i - 1;
if (!found_start) {
/* Command line did not contain alphanumeric word. */
return NULL;
}
ipl = interrupts_disable();
spinlock_lock(&cmd_lock);
for (cur = cmd_head.next; cur != &cmd_head; cur = cur->next) {
cmd_info_t *hlp;
hlp = list_get_instance(cur, cmd_info_t, link);
spinlock_lock(&hlp->lock);
if (strcmp(hlp
->name
, &cmdline
[start
], (end
- start
) + 1) == 0) { cmd = hlp;
break;
}
spinlock_unlock(&hlp->lock);
}
spinlock_unlock(&cmd_lock);
if (!cmd) {
/* Unknown command. */
interrupts_restore(ipl);
return NULL;
}
/* cmd == hlp is locked */
/*
* TODO:
* The command line must be further analyzed and
* the parameters therefrom must be matched and
* converted to those specified in the cmd info
* structure.
*/
spinlock_unlock(&cmd->lock);
interrupts_restore(ipl);
return cmd;
}
/** List supported commands.
*
* @param cmd Argument vector.
*
* @return 0 on failure, 1 on success.
*/
int cmd_help(cmd_arg_t *cmd)
{
link_t *cur;
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&cmd_lock);
for (cur = cmd_head.next; cur != &cmd_head; cur = cur->next) {
cmd_info_t *hlp;
hlp = list_get_instance(cur, cmd_info_t, link);
spinlock_lock(&hlp->lock);
printf("%s\t%s\n", hlp
->name
, hlp
->description
);
spinlock_unlock(&hlp->lock);
}
spinlock_unlock(&cmd_lock);
interrupts_restore(ipl);
return 1;
}