grub/grub-core/kern/main.c
Matthew Garrett 1fe26ab4a0 * grub-core/kern/main.c (grub_set_prefix_and_root): Set variable
cmdpath to firmware directory.
2013-11-14 15:53:32 +01:00

312 lines
7.4 KiB
C

/* main.c - the kernel main routine */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2002,2003,2005,2006,2008,2009 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/misc.h>
#include <grub/symbol.h>
#include <grub/dl.h>
#include <grub/term.h>
#include <grub/file.h>
#include <grub/device.h>
#include <grub/env.h>
#include <grub/mm.h>
#include <grub/command.h>
#include <grub/reader.h>
#include <grub/parser.h>
#ifdef GRUB_MACHINE_PCBIOS
#include <grub/machine/memory.h>
#endif
grub_addr_t
grub_modules_get_end (void)
{
struct grub_module_info *modinfo;
modinfo = (struct grub_module_info *) grub_modbase;
/* Check if there are any modules. */
if ((modinfo == 0) || modinfo->magic != GRUB_MODULE_MAGIC)
return grub_modbase;
return grub_modbase + modinfo->size;
}
/* Load all modules in core. */
static void
grub_load_modules (void)
{
struct grub_module_header *header;
FOR_MODULES (header)
{
/* Not an ELF module, skip. */
if (header->type != OBJ_TYPE_ELF)
continue;
if (! grub_dl_load_core ((char *) header + sizeof (struct grub_module_header),
(header->size - sizeof (struct grub_module_header))))
grub_fatal ("%s", grub_errmsg);
if (grub_errno)
grub_print_error ();
}
}
static char *load_config;
static void
grub_load_config (void)
{
struct grub_module_header *header;
FOR_MODULES (header)
{
/* Not an embedded config, skip. */
if (header->type != OBJ_TYPE_CONFIG)
continue;
load_config = grub_malloc (header->size - sizeof (struct grub_module_header) + 1);
if (!load_config)
{
grub_print_error ();
break;
}
grub_memcpy (load_config, (char *) header +
sizeof (struct grub_module_header),
header->size - sizeof (struct grub_module_header));
load_config[header->size - sizeof (struct grub_module_header)] = 0;
break;
}
}
/* Write hook for the environment variables of root. Remove surrounding
parentheses, if any. */
static char *
grub_env_write_root (struct grub_env_var *var __attribute__ ((unused)),
const char *val)
{
/* XXX Is it better to check the existence of the device? */
grub_size_t len = grub_strlen (val);
if (val[0] == '(' && val[len - 1] == ')')
return grub_strndup (val + 1, len - 2);
return grub_strdup (val);
}
static void
grub_set_prefix_and_root (void)
{
char *device = NULL;
char *path = NULL;
char *fwdevice = NULL;
char *fwpath = NULL;
char *prefix = NULL;
struct grub_module_header *header;
FOR_MODULES (header)
if (header->type == OBJ_TYPE_PREFIX)
prefix = (char *) header + sizeof (struct grub_module_header);
grub_register_variable_hook ("root", 0, grub_env_write_root);
grub_machine_get_bootlocation (&fwdevice, &fwpath);
if (fwdevice)
{
char *cmdpath;
cmdpath = grub_xasprintf ("(%s)%s", fwdevice, fwpath ? : "");
if (cmdpath)
{
grub_env_set ("cmdpath", cmdpath);
grub_env_export ("cmdpath");
grub_free (cmdpath);
}
}
if (prefix)
{
char *pptr = NULL;
if (prefix[0] == '(')
{
pptr = grub_strrchr (prefix, ')');
if (pptr)
{
device = grub_strndup (prefix + 1, pptr - prefix - 1);
pptr++;
}
}
if (!pptr)
pptr = prefix;
if (pptr[0])
path = grub_strdup (pptr);
}
if (!device && fwdevice)
device = fwdevice;
else if (fwdevice && (device[0] == ',' || !device[0]))
{
/* We have a partition, but still need to fill in the drive. */
char *comma, *new_device;
for (comma = fwdevice; *comma; )
{
if (comma[0] == '\\' && comma[1] == ',')
{
comma += 2;
continue;
}
if (*comma == ',')
break;
comma++;
}
if (*comma)
{
char *drive = grub_strndup (fwdevice, comma - fwdevice);
new_device = grub_xasprintf ("%s%s", drive, device);
grub_free (drive);
}
else
new_device = grub_xasprintf ("%s%s", fwdevice, device);
grub_free (fwdevice);
grub_free (device);
device = new_device;
}
else
grub_free (fwdevice);
if (fwpath && !path)
{
grub_size_t len = grub_strlen (fwpath);
while (len > 1 && fwpath[len - 1] == '/')
fwpath[--len] = 0;
if (len >= sizeof (GRUB_TARGET_CPU "-" GRUB_PLATFORM) - 1
&& grub_memcmp (fwpath + len - (sizeof (GRUB_TARGET_CPU "-" GRUB_PLATFORM) - 1), GRUB_TARGET_CPU "-" GRUB_PLATFORM,
sizeof (GRUB_TARGET_CPU "-" GRUB_PLATFORM) - 1) == 0)
fwpath[len - (sizeof (GRUB_TARGET_CPU "-" GRUB_PLATFORM) - 1)] = 0;
path = fwpath;
}
else
grub_free (fwpath);
if (device)
{
char *prefix_set;
prefix_set = grub_xasprintf ("(%s)%s", device, path ? : "");
if (prefix_set)
{
grub_env_set ("prefix", prefix_set);
grub_free (prefix_set);
}
grub_env_set ("root", device);
}
grub_free (device);
grub_free (path);
grub_print_error ();
}
/* Load the normal mode module and execute the normal mode if possible. */
static void
grub_load_normal_mode (void)
{
/* Load the module. */
grub_dl_load ("normal");
/* Print errors if any. */
grub_print_error ();
grub_errno = 0;
grub_command_execute ("normal", 0, 0);
}
static void
reclaim_module_space (void)
{
grub_addr_t modstart, modend;
if (!grub_modbase)
return;
#ifdef GRUB_MACHINE_PCBIOS
modstart = GRUB_MEMORY_MACHINE_DECOMPRESSION_ADDR;
#else
modstart = grub_modbase;
#endif
modend = grub_modules_get_end ();
grub_modbase = 0;
#if GRUB_KERNEL_PRELOAD_SPACE_REUSABLE
grub_mm_init_region ((void *) modstart, modend - modstart);
#else
(void) modstart;
(void) modend;
#endif
}
/* The main routine. */
void __attribute__ ((noreturn))
grub_main (void)
{
/* First of all, initialize the machine. */
grub_machine_init ();
grub_boot_time ("After machine init.");
/* Hello. */
grub_setcolorstate (GRUB_TERM_COLOR_HIGHLIGHT);
grub_printf ("Welcome to GRUB!\n\n");
grub_setcolorstate (GRUB_TERM_COLOR_STANDARD);
grub_load_config ();
grub_boot_time ("Before loading embedded modules.");
/* Load pre-loaded modules and free the space. */
grub_register_exported_symbols ();
#ifdef GRUB_LINKER_HAVE_INIT
grub_arch_dl_init_linker ();
#endif
grub_load_modules ();
grub_boot_time ("After loading embedded modules.");
/* It is better to set the root device as soon as possible,
for convenience. */
grub_set_prefix_and_root ();
grub_env_export ("root");
grub_env_export ("prefix");
/* Reclaim space used for modules. */
reclaim_module_space ();
grub_boot_time ("After reclaiming module space.");
grub_register_core_commands ();
grub_boot_time ("Before execution of embedded config.");
if (load_config)
grub_parser_execute (load_config);
grub_boot_time ("After execution of embedded config. Attempt to go to normal mode");
grub_load_normal_mode ();
grub_rescue_run ();
}