grub/normal/main.c
2009-06-10 21:04:23 +00:00

573 lines
12 KiB
C

/* main.c - the normal mode main routine */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2000,2001,2002,2003,2005,2006,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/kernel.h>
#include <grub/normal.h>
#include <grub/dl.h>
#include <grub/misc.h>
#include <grub/file.h>
#include <grub/mm.h>
#include <grub/term.h>
#include <grub/env.h>
#include <grub/parser.h>
#include <grub/reader.h>
#include <grub/menu_viewer.h>
#define GRUB_DEFAULT_HISTORY_SIZE 50
/* Read a line from the file FILE. */
char *
grub_file_getline (grub_file_t file)
{
char c;
int pos = 0;
int literal = 0;
char *cmdline;
int max_len = 64;
/* Initially locate some space. */
cmdline = grub_malloc (max_len);
if (! cmdline)
return 0;
while (1)
{
if (grub_file_read (file, &c, 1) != 1)
break;
/* Skip all carriage returns. */
if (c == '\r')
continue;
/* Replace tabs with spaces. */
if (c == '\t')
c = ' ';
/* The previous is a backslash, then... */
if (literal)
{
/* If it is a newline, replace it with a space and continue. */
if (c == '\n')
{
c = ' ';
/* Go back to overwrite the backslash. */
if (pos > 0)
pos--;
}
literal = 0;
}
if (c == '\\')
literal = 1;
if (pos == 0)
{
if (! grub_isspace (c))
cmdline[pos++] = c;
}
else
{
if (pos >= max_len)
{
char *old_cmdline = cmdline;
max_len = max_len * 2;
cmdline = grub_realloc (cmdline, max_len);
if (! cmdline)
{
grub_free (old_cmdline);
return 0;
}
}
if (c == '\n')
break;
cmdline[pos++] = c;
}
}
cmdline[pos] = '\0';
/* If the buffer is empty, don't return anything at all. */
if (pos == 0)
{
grub_free (cmdline);
cmdline = 0;
}
return cmdline;
}
static void
free_menu (grub_menu_t menu)
{
grub_menu_entry_t entry = menu->entry_list;
while (entry)
{
grub_menu_entry_t next_entry = entry->next;
grub_free ((void *) entry->title);
grub_free ((void *) entry->sourcecode);
entry = next_entry;
}
grub_free (menu);
grub_env_unset_data_slot ("menu");
}
static void
free_menu_entry_classes (struct grub_menu_entry_class *head)
{
/* Free all the classes. */
while (head)
{
struct grub_menu_entry_class *next;
grub_free (head->name);
next = head->next;
grub_free (head);
head = next;
}
}
/* Add a menu entry to the current menu context (as given by the environment
variable data slot `menu'). As the configuration file is read, the script
parser calls this when a menu entry is to be created. */
grub_err_t
grub_normal_add_menu_entry (int argc, const char **args,
const char *sourcecode)
{
const char *menutitle = 0;
const char *menusourcecode;
grub_menu_t menu;
grub_menu_entry_t *last;
int failed = 0;
int i;
struct grub_menu_entry_class *classes_head; /* Dummy head node for list. */
struct grub_menu_entry_class *classes_tail;
/* Allocate dummy head node for class list. */
classes_head = grub_malloc (sizeof (struct grub_menu_entry_class));
if (! classes_head)
return grub_errno;
classes_head->name = 0;
classes_head->next = 0;
classes_tail = classes_head;
menu = grub_env_get_data_slot ("menu");
if (! menu)
return grub_error (GRUB_ERR_MENU, "no menu context");
last = &menu->entry_list;
menusourcecode = grub_strdup (sourcecode);
if (! menusourcecode)
return grub_errno;
/* Parse menu arguments. */
for (i = 0; i < argc; i++)
{
/* Capture arguments. */
if (grub_strncmp ("--", args[i], 2) == 0)
{
const char *arg = &args[i][2];
/* Handle menu class. */
if (grub_strcmp(arg, "class") == 0)
{
char *class_name;
struct grub_menu_entry_class *new_class;
i++;
class_name = grub_strdup (args[i]);
if (! class_name)
{
failed = 1;
break;
}
/* Create a new class and add it at the tail of the list. */
new_class = grub_malloc (sizeof (struct grub_menu_entry_class));
if (! new_class)
{
grub_free (class_name);
failed = 1;
break;
}
/* Fill in the new class node. */
new_class->name = class_name;
new_class->next = 0;
/* Link the tail to it, and make it the new tail. */
classes_tail->next = new_class;
classes_tail = new_class;
continue;
}
else
{
/* Handle invalid argument. */
failed = 1;
grub_error (GRUB_ERR_MENU,
"invalid argument for menuentry: %s", args[i]);
break;
}
}
/* Capture title. */
if (! menutitle)
{
menutitle = grub_strdup (args[i]);
}
else
{
failed = 1;
grub_error (GRUB_ERR_MENU,
"too many titles for menuentry: %s", args[i]);
break;
}
}
/* Validate arguments. */
if ((! failed) && (! menutitle))
{
grub_error (GRUB_ERR_MENU, "menuentry is missing title");
failed = 1;
}
/* If argument parsing failed, free any allocated resources. */
if (failed)
{
free_menu_entry_classes (classes_head);
grub_free ((void *) menutitle);
grub_free ((void *) menusourcecode);
/* Here we assume that grub_error has been used to specify failure details. */
return grub_errno;
}
/* Add the menu entry at the end of the list. */
while (*last)
last = &(*last)->next;
*last = grub_malloc (sizeof (**last));
if (! *last)
{
free_menu_entry_classes (classes_head);
grub_free ((void *) menutitle);
grub_free ((void *) menusourcecode);
return grub_errno;
}
(*last)->title = menutitle;
(*last)->classes = classes_head;
(*last)->next = 0;
(*last)->sourcecode = menusourcecode;
menu->size++;
return GRUB_ERR_NONE;
}
static grub_menu_t
read_config_file (const char *config)
{
grub_file_t file;
grub_parser_t old_parser = 0;
auto grub_err_t getline (char **line, int cont);
grub_err_t getline (char **line, int cont __attribute__ ((unused)))
{
while (1)
{
char *buf;
*line = buf = grub_file_getline (file);
if (! buf)
return grub_errno;
if (buf[0] == '#')
{
if (buf[1] == '!')
{
grub_parser_t parser;
grub_named_list_t list;
buf += 2;
while (grub_isspace (*buf))
buf++;
if (! old_parser)
old_parser = grub_parser_get_current ();
list = GRUB_AS_NAMED_LIST (grub_parser_class.handler_list);
parser = grub_named_list_find (list, buf);
if (parser)
grub_parser_set_current (parser);
else
{
char cmd_name[8 + grub_strlen (buf)];
/* Perhaps it's not loaded yet, try the autoload
command. */
grub_strcpy (cmd_name, "parser.");
grub_strcat (cmd_name, buf);
grub_command_execute (cmd_name, 0, 0);
}
}
grub_free (*line);
}
else
break;
}
return GRUB_ERR_NONE;
}
grub_menu_t newmenu;
newmenu = grub_env_get_data_slot ("menu");
if (! newmenu)
{
newmenu = grub_malloc (sizeof (*newmenu));
if (! newmenu)
return 0;
newmenu->size = 0;
newmenu->entry_list = 0;
grub_env_set_data_slot ("menu", newmenu);
}
/* Try to open the config file. */
file = grub_file_open (config);
if (! file)
return 0;
grub_reader_loop (getline);
grub_file_close (file);
if (old_parser)
grub_parser_set_current (old_parser);
return newmenu;
}
/* Initialize the screen. */
void
grub_normal_init_page (void)
{
grub_uint8_t width, margin;
#define TITLE ("GNU GRUB version " PACKAGE_VERSION)
width = grub_getwh () >> 8;
margin = (width - (sizeof(TITLE) + 7)) / 2;
grub_cls ();
grub_putchar ('\n');
while (margin--)
grub_putchar (' ');
grub_printf ("%s\n\n", TITLE);
#undef TITLE
}
static int reader_nested;
/* Read the config file CONFIG and execute the menu interface or
the command line interface if BATCH is false. */
void
grub_normal_execute (const char *config, int nested, int batch)
{
grub_menu_t menu = 0;
read_command_list ();
read_fs_list ();
read_handler_list ();
grub_command_execute ("parser.sh", 0, 0);
reader_nested = nested;
if (config)
{
menu = read_config_file (config);
/* Ignore any error. */
grub_errno = GRUB_ERR_NONE;
}
if (! batch)
{
if (menu && menu->size)
{
grub_menu_viewer_show_menu (menu, nested);
if (nested)
free_menu (menu);
}
}
}
/* This starts the normal mode. */
void
grub_enter_normal_mode (const char *config)
{
grub_normal_execute (config, 0, 0);
}
/* Enter normal mode from rescue mode. */
static grub_err_t
grub_cmd_normal (struct grub_command *cmd,
int argc, char *argv[])
{
grub_unregister_command (cmd);
if (argc == 0)
{
/* Guess the config filename. It is necessary to make CONFIG static,
so that it won't get broken by longjmp. */
static char *config;
const char *prefix;
prefix = grub_env_get ("prefix");
if (prefix)
{
config = grub_malloc (grub_strlen (prefix) + sizeof ("/grub.cfg"));
if (! config)
goto quit;
grub_sprintf (config, "%s/grub.cfg", prefix);
grub_enter_normal_mode (config);
grub_free (config);
}
else
grub_enter_normal_mode (0);
}
else
grub_enter_normal_mode (argv[0]);
quit:
return 0;
}
void
grub_cmdline_run (int nested)
{
grub_reader_t reader = grub_reader_get_current ();
reader_nested = nested;
if (reader->init)
reader->init ();
grub_reader_loop (0);
}
static grub_err_t
grub_normal_reader_init (void)
{
grub_normal_init_page ();
grub_setcursor (1);
grub_printf ("\
[ Minimal BASH-like line editing is supported. For the first word, TAB\n\
lists possible command completions. Anywhere else TAB lists possible\n\
device/file completions.%s ]\n\n",
reader_nested ? " ESC at any time exits." : "");
return 0;
}
static char cmdline[GRUB_MAX_CMDLINE];
static grub_err_t
grub_normal_read_line (char **line, int cont)
{
grub_parser_t parser = grub_parser_get_current ();
char prompt[8 + grub_strlen (parser->name)];
grub_sprintf (prompt, "%s:%s> ", parser->name, (cont) ? "" : "grub");
while (1)
{
cmdline[0] = 0;
if (grub_cmdline_get (prompt, cmdline, sizeof (cmdline), 0, 1))
break;
if ((reader_nested) || (cont))
{
*line = 0;
return grub_errno;
}
}
*line = grub_strdup (cmdline);
return 0;
}
static struct grub_reader grub_normal_reader =
{
.name = "normal",
.init = grub_normal_reader_init,
.read_line = grub_normal_read_line
};
static char *
grub_env_write_pager (struct grub_env_var *var __attribute__ ((unused)),
const char *val)
{
grub_set_more ((*val == '1'));
return grub_strdup (val);
}
GRUB_MOD_INIT(normal)
{
/* Normal mode shouldn't be unloaded. */
if (mod)
grub_dl_ref (mod);
grub_menu_viewer_register (&grub_normal_text_menu_viewer);
grub_set_history (GRUB_DEFAULT_HISTORY_SIZE);
grub_reader_register ("normal", &grub_normal_reader);
grub_reader_set_current (&grub_normal_reader);
grub_register_variable_hook ("pager", 0, grub_env_write_pager);
/* Register a command "normal" for the rescue mode. */
grub_register_command_prio ("normal", grub_cmd_normal,
0, "Enter normal mode", 0);
/* Reload terminal colors when these variables are written to. */
grub_register_variable_hook ("color_normal", NULL, grub_env_write_color_normal);
grub_register_variable_hook ("color_highlight", NULL, grub_env_write_color_highlight);
/* Preserve hooks after context changes. */
grub_env_export ("color_normal");
grub_env_export ("color_highlight");
}
GRUB_MOD_FINI(normal)
{
grub_set_history (0);
grub_reader_unregister (&grub_normal_reader);
grub_register_variable_hook ("pager", 0, 0);
grub_fs_autoload_hook = 0;
free_handler_list ();
}