diff options
Diffstat (limited to 'fish/alloc.c')
-rw-r--r-- | fish/alloc.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/fish/alloc.c b/fish/alloc.c new file mode 100644 index 00000000..8979acf4 --- /dev/null +++ b/fish/alloc.c @@ -0,0 +1,111 @@ +/* guestfish - the filesystem interactive shell + * Copyright (C) 2009 Red Hat Inc. + * + * This program 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 2 of the License, or + * (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <inttypes.h> + +#include "fish.h" + +static int parse_size (const char *str, off_t *size_rtn); + +int +do_alloc (int argc, char *argv[]) +{ + off_t size; + int fd; + + if (argc != 2) { + fprintf (stderr, "use 'alloc file size' to create an image\n"); + return -1; + } + + if (parse_size (argv[1], &size) == -1) + return -1; + + if (g_launched) { + fprintf (stderr, "can't allocate or add disks after launching\n"); + return -1; + } + + fd = open (argv[0], O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK|O_TRUNC, 0666); + if (fd == -1) { + perror (argv[0]); + return -1; + } + + if (posix_fallocate (fd, 0, size) == -1) { + perror ("fallocate"); + close (fd); + unlink (argv[0]); + return -1; + } + + if (close (fd) == -1) { + perror (argv[0]); + unlink (argv[0]); + return -1; + } + + if (guestfs_add_drive (g, argv[0]) == -1) { + unlink (argv[0]); + return -1; + } + + return 0; +} + +static int +parse_size (const char *str, off_t *size_rtn) +{ + uint64_t size; + char type; + + /* Note that the parsing here is looser than what is specified in the + * help, but we may tighten it up in future so beware. + */ + if (sscanf (str, "%"SCNu64"%c", &size, &type) == 2) { + switch (type) { + case 'k': case 'K': size *= 1024; break; + case 'm': case 'M': size *= 1024 * 1024; break; + case 'g': case 'G': size *= 1024 * 1024 * 1024; break; + case 's': size *= 512; break; + default: + fprintf (stderr, "could not parse size specification '%s'\n", str); + return -1; + } + } + else if (sscanf (str, "%"SCNu64, &size) == 1) + size *= 1024; + else { + fprintf (stderr, "could not parse size specification '%s'\n", str); + return -1; + } + + /* XXX 32 bit file offsets, if anyone uses them? GCC should give + * a warning here anyhow. + */ + *size_rtn = size; + + return 0; +} |