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Re: [PATCH] cpio and tar filesystem
From: |
Bean |
Subject: |
Re: [PATCH] cpio and tar filesystem |
Date: |
Mon, 24 Dec 2007 12:40:06 +0800 |
On Dec 24, 2007 5:48 AM, Robert Millan <address@hidden> wrote:
>Perhaps it'd be a good idea to move the arch-independant part of
>grub_emu_SOURCES to common.rmk (as grub_emu_SOURCES += foo), to avoid
>having to update all the files so often ...
yes, but i think it should be in a separate patch.
> > +struct HEAD_USTAR
> > +{
> > + char name[100];
> > + char mode[8];
> > + char uid[8];
> > + char gid[8];
> > + char size[12];
> > + char mtime[12];
> > + char chksum[8];
> > + char typeflag;
> > + char linkname[100];
> > + char magic[6];
> > + char version[2];
> > + char uname[32];
> > + char gname[32];
> > + char devmajor[8];
> > + char devminor[8];
> > + char prefix[155];
>
> These tabs should be spaces.
done.
>
> > + if (grub_disk_read (data->disk, 0, data->hofs, sizeof(hd),
> > (char*)&hd))
> > [...]
> > + if (grub_disk_read (data->disk, 0, data->hofs, sizeof(hd),
> > (char*)&hd))
>
> `(char *) &hd' here (same for all other casts).
>
> Btw, this line seems to be the same on both cases. It can be moved out of
> `if (data->mode == MODE_BCPIO)' to save some space?
>
In fact, it's not the same, in the first case, hd is of type
HEAD_BCPIO, while in the second case, hd is of type HEAD_USTAR.The two
structure has different size.
> > + if (hd.namesize & 1)
> > + hd.namesize++;
> > [...]
> > + if (data->size & 1)
> > + (*ofs)++;
>
> I find this confusing. AFAICT `hd.namesize == 1' would archieve the same and
> seems to be more consistent with your use of this variable as a counter.
>
When the name size is odd number, cpio pad another byte to make it
word align, and the same apply to file size. However, I want to keep
the original file size, so it use (*ofs)++ instead of data->size++.
> > + if ((*name = grub_malloc (hd.namesize))==NULL)
> > [...]
> > + if ((*name = grub_strdup (hd.name))==NULL)
>
> Please add some spaces: ` == NULL'
>
> > + if (grub_memcmp(hd.magic, MAGIC_USTAR, sizeof(MAGIC_USTAR) - 1))
> > [...]
> > + data->size = grub_strtoul(hd.size, NULL, 8);
>
> `grub_memcmp (', `grub_strtoul (', etc. Same for other function calls.
>
> > + return (grub_disk_read (data->disk, 0, data->dofs + file->offset,
> > + len, buf))?-1:len;
>
> ` ? -1 : len'
>
done.
> > +#ifndef GRUB_UTIL
> > + grub_dl_unref (my_mod);
> > +#endif
> > [...]
> > +#ifndef GRUB_UTIL
> > + my_mod = mod;
> > +#endif
>
> Are you sure these are still needed? We have a few modules that use them but
> AFAIK are not necessary at this time.
This is needed, the my_mod variable is used to stored the module
pointer, and we need it to increase the module reference when a file
is opened, so that the modules can't be unloaded.
Here is the new patch.
2007-12-24 Bean <address@hidden>
* conf/common.rmk (pkgdata_MODULES): Add cpio.mod.
(cpio_mod_SOURCES): New variable.
(cpio_mod_CFLAGS): Likewise.
(cpio_mod_LDFLAGS): Likewise.
* fs/cpio.c: New file.
* conf/i386-pc.rmk (grub_emu_SOURCES): Add cpio.c.
* conf/i386-efi.rmk (grub_emu_SOURCES): Likewise.
* conf/i386-linuxbios.rmk (grub_emu_SOURCES): Likewise.
* conf/powerpc-ieee1275.rmk (grub_emu_SOURCES): Likewise.
diff --git a/conf/common.rmk b/conf/common.rmk
index 0e6b81b..72edb37 100644
--- a/conf/common.rmk
+++ b/conf/common.rmk
@@ -81,7 +81,7 @@ update-grub_DATA += util/grub.d/README
# Filing systems.
pkgdata_MODULES += fshelp.mod fat.mod ufs.mod ext2.mod ntfs.mod
\
ntfscomp.mod minix.mod hfs.mod jfs.mod iso9660.mod xfs.mod \
- affs.mod sfs.mod hfsplus.mod
+ affs.mod sfs.mod hfsplus.mod cpio.mod
# For fshelp.mod.
fshelp_mod_SOURCES = fs/fshelp.c
@@ -153,6 +153,11 @@ hfsplus_mod_SOURCES = fs/hfsplus.c
hfsplus_mod_CFLAGS = $(COMMON_CFLAGS)
hfsplus_mod_LDFLAGS = $(COMMON_LDFLAGS)
+# For cpio.mod.
+cpio_mod_SOURCES = fs/cpio.c
+cpio_mod_CFLAGS = $(COMMON_CFLAGS)
+cpio_mod_LDFLAGS = $(COMMON_LDFLAGS)
+
# Partition maps.
pkgdata_MODULES += amiga.mod apple.mod pc.mod sun.mod acorn.mod gpt.mod
diff --git a/conf/i386-efi.rmk b/conf/i386-efi.rmk
index 305cbe4..397cfbb 100644
--- a/conf/i386-efi.rmk
+++ b/conf/i386-efi.rmk
@@ -51,7 +51,7 @@ grub_emu_SOURCES = commands/boot.c commands/cat.c
commands/cmp.c \
disk/loopback.c \
fs/affs.c fs/ext2.c fs/fat.c fs/fshelp.c fs/hfs.c fs/iso9660.c \
fs/jfs.c fs/minix.c fs/sfs.c fs/ufs.c fs/xfs.c fs/hfsplus.c \
- fs/ntfs.c fs/ntfscomp.c \
+ fs/ntfs.c fs/ntfscomp.c fs/cpio.c \
io/gzio.c \
kern/device.c kern/disk.c kern/dl.c kern/elf.c kern/env.c \
kern/err.c \
diff --git a/conf/i386-linuxbios.rmk b/conf/i386-linuxbios.rmk
index 8b98d3b..c33d937 100644
--- a/conf/i386-linuxbios.rmk
+++ b/conf/i386-linuxbios.rmk
@@ -76,7 +76,7 @@ grub_emu_SOURCES = commands/boot.c commands/cat.c
commands/cmp.c \
disk/host.c disk/loopback.c disk/raid.c disk/lvm.c \
fs/affs.c fs/ext2.c fs/fat.c fs/fshelp.c fs/hfs.c fs/iso9660.c \
fs/jfs.c fs/minix.c fs/sfs.c fs/ufs.c fs/xfs.c fs/hfsplus.c \
- fs/ntfs.c fs/ntfscomp.c \
+ fs/ntfs.c fs/ntfscomp.c fs/cpio.c \
io/gzio.c \
kern/device.c kern/disk.c kern/dl.c kern/elf.c kern/env.c \
kern/err.c \
diff --git a/conf/i386-pc.rmk b/conf/i386-pc.rmk
index 8c100d7..8e0f31b 100644
--- a/conf/i386-pc.rmk
+++ b/conf/i386-pc.rmk
@@ -103,7 +103,7 @@ grub_emu_SOURCES = commands/boot.c commands/cat.c
commands/cmp.c \
disk/host.c disk/loopback.c disk/raid.c disk/lvm.c \
fs/affs.c fs/ext2.c fs/fat.c fs/fshelp.c fs/hfs.c fs/iso9660.c \
fs/jfs.c fs/minix.c fs/sfs.c fs/ufs.c fs/xfs.c fs/hfsplus.c \
- fs/ntfs.c fs/ntfscomp.c \
+ fs/ntfs.c fs/ntfscomp.c fs/cpio.c \
io/gzio.c \
kern/device.c kern/disk.c kern/dl.c kern/elf.c kern/env.c \
kern/err.c \
diff --git a/conf/powerpc-ieee1275.rmk b/conf/powerpc-ieee1275.rmk
index eb440f1..af0773b 100644
--- a/conf/powerpc-ieee1275.rmk
+++ b/conf/powerpc-ieee1275.rmk
@@ -62,7 +62,7 @@ grub_emu_SOURCES = commands/boot.c commands/cat.c
commands/cmp.c \
disk/loopback.c \
fs/affs.c fs/ext2.c fs/fat.c fs/fshelp.c fs/hfs.c fs/iso9660.c \
fs/jfs.c fs/minix.c fs/sfs.c fs/ufs.c fs/xfs.c fs/hfsplus.c \
- fs/ntfs.c fs/ntfscomp.c \
+ fs/ntfs.c fs/ntfscomp.c fs/cpio.c \
io/gzio.c \
kern/device.c kern/disk.c kern/dl.c kern/elf.c kern/env.c \
kern/err.c kern/file.c kern/fs.c kern/loader.c kern/main.c \
diff --git a/fs/cpio.c b/fs/cpio.c
new file mode 100755
index 0000000..48e0514
--- /dev/null
+++ b/fs/cpio.c
@@ -0,0 +1,348 @@
+/* cpio.c - cpio and tar filesystem. */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2007 Free Software Foundation, 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/file.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/disk.h>
+#include <grub/dl.h>
+
+#define MAGIC_BCPIO 070707
+
+struct HEAD_BCPIO
+{
+ grub_uint16_t magic;
+ grub_uint16_t dev;
+ grub_uint16_t ino;
+ grub_uint16_t mode;
+ grub_uint16_t uid;
+ grub_uint16_t gid;
+ grub_uint16_t nlink;
+ grub_uint16_t rdev;
+ grub_uint16_t mtime_1;
+ grub_uint16_t mtime_2;
+ grub_uint16_t namesize;
+ grub_uint16_t filesize_1;
+ grub_uint16_t filesize_2;
+} __attribute__ ((packed));
+
+#define MAGIC_USTAR "ustar"
+
+struct HEAD_USTAR
+{
+ char name[100];
+ char mode[8];
+ char uid[8];
+ char gid[8];
+ char size[12];
+ char mtime[12];
+ char chksum[8];
+ char typeflag;
+ char linkname[100];
+ char magic[6];
+ char version[2];
+ char uname[32];
+ char gname[32];
+ char devmajor[8];
+ char devminor[8];
+ char prefix[155];
+} __attribute__ ((packed));
+
+#define HEAD_LENG sizeof(struct HEAD_USTAR)
+
+#define MODE_BCPIO 1
+#define MODE_USTAR 2
+
+struct grub_cpio_data
+{
+ grub_disk_t disk;
+ grub_uint32_t hofs;
+ grub_uint32_t dofs;
+ grub_uint32_t size;
+ int mode;
+};
+
+#ifndef GRUB_UTIL
+static grub_dl_t my_mod;
+#endif
+
+static grub_err_t
+grub_cpio_find_file (struct grub_cpio_data *data, char **name,
+ grub_uint32_t * ofs)
+{
+ if (data->mode == MODE_BCPIO)
+ {
+ struct HEAD_BCPIO hd;
+
+ if (grub_disk_read
+ (data->disk, 0, data->hofs, sizeof (hd), (char *) &hd))
+ return grub_errno;
+
+ if (hd.magic != MAGIC_BCPIO)
+ return grub_error (GRUB_ERR_BAD_FS, "Invalid cpio archive");
+
+ data->size = (((grub_uint32_t) hd.filesize_1) << 16) + hd.filesize_2;
+ if (data->size == 0)
+ {
+ *ofs = 0;
+ return GRUB_ERR_NONE;
+ }
+
+ if (hd.namesize & 1)
+ hd.namesize++;
+
+ if ((*name = grub_malloc (hd.namesize)) == NULL)
+ return grub_errno;
+
+ if (grub_disk_read (data->disk, 0, data->hofs + sizeof (hd),
+ hd.namesize, *name))
+ {
+ grub_free (*name);
+ return grub_errno;
+ }
+
+ data->dofs = data->hofs + sizeof (hd) + hd.namesize;
+ *ofs = data->dofs + data->size;
+ if (data->size & 1)
+ (*ofs)++;
+ }
+ else
+ {
+ struct HEAD_USTAR hd;
+
+ if (grub_disk_read
+ (data->disk, 0, data->hofs, sizeof (hd), (char *) &hd))
+ return grub_errno;
+
+ if (!hd.name[0])
+ {
+ *ofs = 0;
+ return GRUB_ERR_NONE;
+ }
+
+ if (grub_memcmp (hd.magic, MAGIC_USTAR, sizeof (MAGIC_USTAR) - 1))
+ return grub_error (GRUB_ERR_BAD_FS, "Invalid tar archive");
+
+ if ((*name = grub_strdup (hd.name)) == NULL)
+ return grub_errno;
+
+ data->size = grub_strtoul (hd.size, NULL, 8);
+ data->dofs = data->hofs + GRUB_DISK_SECTOR_SIZE;
+ *ofs = data->dofs + ((data->size + GRUB_DISK_SECTOR_SIZE - 1) &
+ ~(GRUB_DISK_SECTOR_SIZE - 1));
+ }
+ return GRUB_ERR_NONE;
+}
+
+static struct grub_cpio_data *
+grub_cpio_mount (grub_disk_t disk)
+{
+ char hd[HEAD_LENG];
+ struct grub_cpio_data *data;
+ int mode;
+
+ if (grub_disk_read (disk, 0, 0, sizeof (hd), hd))
+ goto fail;
+
+ if (((struct HEAD_BCPIO *) hd)->magic == MAGIC_BCPIO)
+ mode = MODE_BCPIO;
+ else if (!grub_memcmp (((struct HEAD_USTAR *) hd)->magic, MAGIC_USTAR,
+ sizeof (MAGIC_USTAR) - 1))
+ mode = MODE_USTAR;
+ else
+ goto fail;
+
+ data = (struct grub_cpio_data *) grub_malloc (sizeof (*data));
+ if (!data)
+ goto fail;
+
+ data->disk = disk;
+ data->mode = mode;
+
+ return data;
+
+fail:
+ grub_error (GRUB_ERR_BAD_FS, "not a cpio filesystem");
+ return 0;
+}
+
+static grub_err_t
+grub_cpio_dir (grub_device_t device, const char *path,
+ int (*hook) (const char *filename, int dir))
+{
+ struct grub_cpio_data *data;
+ grub_uint32_t ofs;
+ char *prev, *name, *np;
+ int len;
+
+#ifndef GRUB_UTIL
+ grub_dl_ref (my_mod);
+#endif
+
+ prev = 0;
+
+ data = grub_cpio_mount (device->disk);
+ if (!data)
+ goto fail;
+
+ np = path + 1;
+ len = grub_strlen (path) - 1;
+
+ data->hofs = 0;
+ while (1)
+ {
+ if (grub_cpio_find_file (data, &name, &ofs))
+ goto fail;
+
+ if (!ofs)
+ break;
+
+ if (grub_memcmp (np, name, len) == 0)
+ {
+ char *p, *n;
+
+ n = name + len;
+ if (*n == '/')
+ n++;
+
+ p = grub_strchr (name + len, '/');
+ if (p)
+ *p = 0;
+
+ if ((!prev) || (grub_strcmp (prev, name) != 0))
+ {
+ hook (name + len, p != NULL);
+ if (prev)
+ grub_free (prev);
+ prev = name;
+ }
+ else
+ grub_free (name);
+ }
+ data->hofs = ofs;
+ }
+
+fail:
+
+ if (prev)
+ grub_free (prev);
+
+ if (data)
+ grub_free (data);
+
+#ifndef GRUB_UTIL
+ grub_dl_unref (my_mod);
+#endif
+
+ return grub_errno;
+}
+
+static grub_err_t
+grub_cpio_open (grub_file_t file, const char *name)
+{
+ struct grub_cpio_data *data;
+ grub_uint32_t ofs;
+ char *fn;
+
+#ifndef GRUB_UTIL
+ grub_dl_ref (my_mod);
+#endif
+
+ data = grub_cpio_mount (file->device->disk);
+ if (!data)
+ goto fail;
+
+ data->hofs = 0;
+ while (1)
+ {
+ if (grub_cpio_find_file (data, &fn, &ofs))
+ goto fail;
+
+ if (!ofs)
+ break;
+
+ if (grub_strcmp (name + 1, fn) == 0)
+ {
+ file->data = data;
+ file->size = data->size;
+ grub_free (fn);
+
+ return GRUB_ERR_NONE;
+ }
+
+ grub_free (fn);
+ data->hofs = ofs;
+ }
+
+fail:
+
+ if (data)
+ grub_free (data);
+
+#ifndef GRUB_UTIL
+ grub_dl_unref (my_mod);
+#endif
+
+ return grub_errno;
+}
+
+static grub_ssize_t
+grub_cpio_read (grub_file_t file, char *buf, grub_size_t len)
+{
+ struct grub_cpio_data *data;
+
+ data = file->data;
+ return (grub_disk_read (data->disk, 0, data->dofs + file->offset,
+ len, buf)) ? -1 : len;
+}
+
+static grub_err_t
+grub_cpio_close (grub_file_t file)
+{
+ grub_free (file->data);
+
+#ifndef GRUB_UTIL
+ grub_dl_unref (my_mod);
+#endif
+
+ return grub_errno;
+}
+
+static struct grub_fs grub_cpio_fs = {
+ .name = "cpiofs",
+ .dir = grub_cpio_dir,
+ .open = grub_cpio_open,
+ .read = grub_cpio_read,
+ .close = grub_cpio_close,
+ .label = 0,
+ .next = 0
+};
+
+GRUB_MOD_INIT (cpio)
+{
+ grub_fs_register (&grub_cpio_fs);
+#ifndef GRUB_UTIL
+ my_mod = mod;
+#endif
+}
+
+GRUB_MOD_FINI (cpio)
+{
+ grub_fs_unregister (&grub_cpio_fs);
+}
--
Bean
Re: [PATCH] cpio and tar filesystem, Robert Millan, 2007/12/23