diff options
Diffstat (limited to 'grub-core/kern/main.c')
| -rw-r--r-- | grub-core/kern/main.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/grub-core/kern/main.c b/grub-core/kern/main.c new file mode 100644 index 0000000..da71232 --- /dev/null +++ b/grub-core/kern/main.c @@ -0,0 +1,200 @@ +/* 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> + +void +grub_module_iterate (int (*hook) (struct grub_module_header *header)) +{ + struct grub_module_info *modinfo; + struct grub_module_header *header; + grub_addr_t modbase; + + modbase = grub_arch_modules_addr (); + modinfo = (struct grub_module_info *) modbase; + + /* Check if there are any modules. */ + if ((modinfo == 0) || modinfo->magic != GRUB_MODULE_MAGIC) + return; + + for (header = (struct grub_module_header *) (modbase + modinfo->offset); + header < (struct grub_module_header *) (modbase + modinfo->size); + header = (struct grub_module_header *) ((char *) header + header->size)) + { + if (hook (header)) + break; + } +} + +/* This is actualy platform-independant but used only on yeeloong and sparc. */ +#if defined (GRUB_MACHINE_MIPS_YEELOONG) || defined (GRUB_MACHINE_SPARC64) +grub_addr_t +grub_modules_get_end (void) +{ + struct grub_module_info *modinfo; + grub_addr_t modbase; + + modbase = grub_arch_modules_addr (); + modinfo = (struct grub_module_info *) modbase; + + /* Check if there are any modules. */ + if ((modinfo == 0) || modinfo->magic != GRUB_MODULE_MAGIC) + return modbase; + + return modbase + modinfo->size; +} +#endif + +/* Load all modules in core. */ +static void +grub_load_modules (void) +{ + auto int hook (struct grub_module_header *); + int hook (struct grub_module_header *header) + { + /* Not an ELF module, skip. */ + if (header->type != OBJ_TYPE_ELF) + return 0; + + 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 (); + + return 0; + } + + grub_module_iterate (hook); +} + +static void +grub_load_config (void) +{ + auto int hook (struct grub_module_header *); + int hook (struct grub_module_header *header) + { + /* Not an embedded config, skip. */ + if (header->type != OBJ_TYPE_CONFIG) + return 0; + + grub_parser_execute ((char *) header + + sizeof (struct grub_module_header)); + return 1; + } + + grub_module_iterate (hook); +} + +/* 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); +} + +/* Set the root device according to the dl prefix. */ +static void +grub_set_root_dev (void) +{ + const char *prefix; + + grub_register_variable_hook ("root", 0, grub_env_write_root); + + prefix = grub_env_get ("prefix"); + + if (prefix) + { + char *dev; + + dev = grub_file_get_device_name (prefix); + if (dev) + { + grub_env_set ("root", dev); + grub_free (dev); + } + } +} + +/* 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"); + + /* Something went wrong. Print errors here to let user know why we're entering rescue mode. */ + grub_print_error (); + grub_errno = 0; + + grub_command_execute ("normal", 0, 0); +} + +/* The main routine. */ +void +grub_main (void) +{ + /* First of all, initialize the machine. */ + grub_machine_init (); + + /* Hello. */ + grub_setcolorstate (GRUB_TERM_COLOR_HIGHLIGHT); + grub_printf ("Welcome to GRUB!\n\n"); + grub_setcolorstate (GRUB_TERM_COLOR_STANDARD); + + /* 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 (); + + /* It is better to set the root device as soon as possible, + for convenience. */ + grub_machine_set_prefix (); + grub_set_root_dev (); + grub_env_export ("root"); + grub_env_export ("prefix"); + + grub_register_core_commands (); + + grub_load_config (); + grub_load_normal_mode (); + grub_rescue_run (); +} |