diff options
Diffstat (limited to 'grub-core/commands/blocklist.c')
| -rw-r--r-- | grub-core/commands/blocklist.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/grub-core/commands/blocklist.c b/grub-core/commands/blocklist.c new file mode 100644 index 0000000..944449b --- /dev/null +++ b/grub-core/commands/blocklist.c @@ -0,0 +1,160 @@ +/* blocklist.c - print the block list of a file */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2006,2007 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/dl.h> +#include <grub/misc.h> +#include <grub/file.h> +#include <grub/mm.h> +#include <grub/disk.h> +#include <grub/partition.h> +#include <grub/command.h> +#include <grub/i18n.h> + +GRUB_MOD_LICENSE ("GPLv3+"); + +/* Context for grub_cmd_blocklist. */ +struct blocklist_ctx +{ + unsigned long start_sector; + unsigned num_sectors; + int num_entries; + grub_disk_addr_t part_start; +}; + +/* Helper for grub_cmd_blocklist. */ +static void +print_blocklist (grub_disk_addr_t sector, unsigned num, + unsigned offset, unsigned length, struct blocklist_ctx *ctx) +{ + if (ctx->num_entries++) + grub_printf (","); + + grub_printf ("%llu", (unsigned long long) (sector - ctx->part_start)); + if (num > 0) + grub_printf ("+%u", num); + if (offset != 0 || length != 0) + grub_printf ("[%u-%u]", offset, offset + length); +} + +/* Helper for grub_cmd_blocklist. */ +static void +read_blocklist (grub_disk_addr_t sector, unsigned offset, unsigned length, + void *data) +{ + struct blocklist_ctx *ctx = data; + + if (ctx->num_sectors > 0) + { + if (ctx->start_sector + ctx->num_sectors == sector + && offset == 0 && length >= GRUB_DISK_SECTOR_SIZE) + { + ctx->num_sectors += length >> GRUB_DISK_SECTOR_BITS; + sector += length >> GRUB_DISK_SECTOR_BITS; + length &= (GRUB_DISK_SECTOR_SIZE - 1); + } + + if (!length) + return; + print_blocklist (ctx->start_sector, ctx->num_sectors, 0, 0, ctx); + ctx->num_sectors = 0; + } + + if (offset) + { + unsigned l = length + offset; + l &= (GRUB_DISK_SECTOR_SIZE - 1); + l -= offset; + print_blocklist (sector, 0, offset, l, ctx); + length -= l; + sector++; + offset = 0; + } + + if (!length) + return; + + if (length & (GRUB_DISK_SECTOR_SIZE - 1)) + { + if (length >> GRUB_DISK_SECTOR_BITS) + { + print_blocklist (sector, length >> GRUB_DISK_SECTOR_BITS, 0, 0, ctx); + sector += length >> GRUB_DISK_SECTOR_BITS; + } + print_blocklist (sector, 0, 0, length & (GRUB_DISK_SECTOR_SIZE - 1), ctx); + } + else + { + ctx->start_sector = sector; + ctx->num_sectors = length >> GRUB_DISK_SECTOR_BITS; + } +} + +static grub_err_t +grub_cmd_blocklist (grub_command_t cmd __attribute__ ((unused)), + int argc, char **args) +{ + grub_file_t file; + char buf[GRUB_DISK_SECTOR_SIZE]; + struct blocklist_ctx ctx = { + .start_sector = 0, + .num_sectors = 0, + .num_entries = 0, + .part_start = 0 + }; + + if (argc < 1) + return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected")); + + file = grub_file_open (args[0], GRUB_FILE_TYPE_PRINT_BLOCKLIST + | GRUB_FILE_TYPE_NO_DECOMPRESS); + if (! file) + return grub_errno; + + if (! file->device->disk) + return grub_error (GRUB_ERR_BAD_DEVICE, + "this command is available only for disk devices"); + + ctx.part_start = grub_partition_get_start (file->device->disk->partition); + + file->read_hook = read_blocklist; + file->read_hook_data = &ctx; + + while (grub_file_read (file, buf, sizeof (buf)) > 0) + ; + + if (ctx.num_sectors > 0) + print_blocklist (ctx.start_sector, ctx.num_sectors, 0, 0, &ctx); + + grub_file_close (file); + + return grub_errno; +} + +static grub_command_t cmd; + +GRUB_MOD_INIT(blocklist) +{ + cmd = grub_register_command ("blocklist", grub_cmd_blocklist, + N_("FILE"), N_("Print a block list.")); +} + +GRUB_MOD_FINI(blocklist) +{ + grub_unregister_command (cmd); +} |