[syslinux] [PATCH 6/9] linux/syslinux: implement write_to_ext() and add syslinuxext.c
Robert Yang
liezhi.yang at windriver.com
Thu Jan 1 21:05:59 PST 2015
* The write_to_ext() write file to the extX device, and handle the boot
sector.
* The syslinuxext.c is used for placing the code which are used by
extlinux and syslinux (which is syslinux_patch_bootsect()).
Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
---
libinstaller/syslinuxext.c | 7 +++
libinstaller/syslinuxext.h | 5 ++
linux/Makefile | 3 +-
linux/syslinux.c | 118 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 132 insertions(+), 1 deletion(-)
create mode 100644 libinstaller/syslinuxext.c
create mode 100644 libinstaller/syslinuxext.h
diff --git a/libinstaller/syslinuxext.c b/libinstaller/syslinuxext.c
new file mode 100644
index 0000000..bb54cef
--- /dev/null
+++ b/libinstaller/syslinuxext.c
@@ -0,0 +1,7 @@
+#define _GNU_SOURCE
+
+/* Patch syslinux_bootsect */
+void syslinux_patch_bootsect(int dev_fd)
+{
+}
+
diff --git a/libinstaller/syslinuxext.h b/libinstaller/syslinuxext.h
new file mode 100644
index 0000000..8abd8b9
--- /dev/null
+++ b/libinstaller/syslinuxext.h
@@ -0,0 +1,5 @@
+#ifndef EXT2_SUPER_OFFSET
+#define EXT2_SUPER_OFFSET 1024
+#endif
+
+void syslinux_patch_bootsect(int dev_fd);
diff --git a/linux/Makefile b/linux/Makefile
index ac1ac58..3b23867 100644
--- a/linux/Makefile
+++ b/linux/Makefile
@@ -30,7 +30,8 @@ SRCS = syslinux.c \
../libinstaller/syslxmod.c \
../libinstaller/bootsect_bin.c \
../libinstaller/ldlinuxc32_bin.c \
- ../libinstaller/ldlinux_bin.c
+ ../libinstaller/ldlinux_bin.c \
+ ../libinstaller/syslinuxext.c
OBJS = $(patsubst %.c,%.o,$(notdir $(SRCS)))
.SUFFIXES: .c .o .i .s .S
diff --git a/linux/syslinux.c b/linux/syslinux.c
index de5d272..f0c97a8 100755
--- a/linux/syslinux.c
+++ b/linux/syslinux.c
@@ -46,6 +46,7 @@
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/mount.h>
+#include <time.h>
#include "linuxioctl.h"
@@ -72,6 +73,7 @@
#include "syslxfs.h"
#include "setadv.h"
#include "syslxopt.h" /* unified options */
+#include "syslinuxext.h"
#include <ext2fs/ext2fs.h>
extern const char *program; /* Name of program */
@@ -419,6 +421,12 @@ int install_bootblock(int fd, const char *device)
{
}
+/* Construct the boot file map */
+int ext_construct_sectmap_fs(ext2_filsys fs, ext2_ino_t newino,
+ sector_t *sectors, int nsect)
+{
+}
+
static int handle_adv_on_ext(void)
{
int i, retval, found_file;
@@ -524,6 +532,116 @@ fail:
static int write_to_ext(const char *filename, const char *str, int length,
int i_flags, int dev_fd, const char *subdir)
{
+ ext2_ino_t newino;
+ struct ext2_inode inode;
+ int retval, i, modbytes, nsect;
+ ext2_file_t e2_file;
+ sector_t *sectors;
+
+ /* Remove it if it is already exists */
+ retval = ext2fs_namei(e2fs, root, cwd, filename, &newino);
+ if (retval == 0) {
+ retval = ext2fs_unlink(e2fs, cwd, filename, newino, 0);
+ if (retval) {
+ fprintf(stderr, "%s: failed to unlink: %s\n", program, filename);
+ return retval;
+ }
+ }
+
+ /* Create new inode */
+ retval = ext2fs_new_inode(e2fs, cwd, 010755, 0, &newino);
+ if (retval) {
+ fprintf(stderr, "%s: ERROR: failed to create inode for: %s\n",
+ program, filename);
+ return retval;
+ }
+
+ /* Link the inode and the filename */
+ retval = ext2fs_link(e2fs, cwd, filename, newino, EXT2_FT_REG_FILE);
+ if (retval) {
+ fprintf(stderr, "%s: ERROR: failed to link inode for: %s.\n",
+ program, filename);
+ return retval;
+ }
+
+ if (ext2fs_test_inode_bitmap2(e2fs->inode_map, newino))
+ fprintf(stderr, "%s: warning: inode already set %s.\n",
+ program, filename);
+
+ ext2fs_inode_alloc_stats2(e2fs, newino, +1, 0);
+ memset(&inode, 0, sizeof(inode));
+ inode.i_mode = LINUX_S_IFREG | LINUX_S_IRUSR | LINUX_S_IRGRP
+ | LINUX_S_IROTH;
+ inode.i_flags |= i_flags;
+ inode.i_atime = inode.i_ctime = inode.i_mtime =
+ e2fs->now ? e2fs->now : time(0);
+ inode.i_links_count = 1;
+ if (e2fs->super->s_feature_incompat &
+ EXT3_FEATURE_INCOMPAT_EXTENTS) {
+ struct ext3_extent_header *eh;
+
+ eh = (struct ext3_extent_header *) &inode.i_block[0];
+ eh->eh_depth = 0;
+ eh->eh_entries = 0;
+ eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC);
+ i = (sizeof(inode.i_block) - sizeof(*eh)) /
+ sizeof(struct ext3_extent);
+ eh->eh_max = ext2fs_cpu_to_le16(i);
+ inode.i_flags |= EXT4_EXTENTS_FL;
+ }
+
+ retval = ext2fs_write_new_inode(e2fs, newino, &inode);
+ if (retval) {
+ fprintf(stderr, "%s: ERROR: while writting inode %d.\n",
+ program, newino);
+ return 1;
+ }
+
+ retval = ext2fs_file_open(e2fs, newino, EXT2_FILE_WRITE, &e2_file);
+ if (retval) {
+ fprintf(stderr, "%s: ERROR: failed to open %s.\n",
+ program, filename);
+ return 1;
+ }
+
+ /* Write to file */
+ if (ext_file_write(e2_file, str, length, 0) == -1)
+ goto fail;
+
+ if (strcmp(filename, "ldlinux.sys") == 0) {
+ /* Write ADV */
+ if (ext_file_write(e2_file, syslinux_adv, 2 * ADV_SIZE,
+ boot_image_len) == -1)
+ goto fail;
+
+ /* Patch syslinux_bootsect */
+ syslinux_patch_bootsect(dev_fd);
+
+ /* Patch ldlinux.sys */
+ nsect = (boot_image_len + SECTOR_SIZE - 1) >> SECTOR_SHIFT;
+ nsect += 2; /* Two sectors for the ADV */
+ sectors = alloca(sizeof(sector_t) * nsect);
+ memset(sectors, 0, nsect * sizeof *sectors);
+ /* The sectors will be modified and used by syslinux_patch() */
+ retval = ext_construct_sectmap_fs(e2fs, newino, sectors, nsect);
+ if (retval)
+ goto fail;
+
+ /* Create the modified image in memory */
+ modbytes = syslinux_patch(sectors, nsect, opt.stupid_mode,
+ opt.raid_mode, subdir, NULL);
+
+ /* Rewrite the first modbytes of ldlinux.sys */
+ if (ext_file_write(e2_file, str, modbytes, 0) == -1) {
+ fprintf(stderr, "%s: ERROR: failed to patch %s.\n", program,
+ filename);
+ goto fail;
+ }
+ }
+
+fail:
+ (void) ext2fs_file_close(e2_file);
+ return retval;
}
/* The install func for ext2, ext3 and ext4 */
--
1.9.1
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