#include "ext2_fs.h"
#include "ext2fs.h"
+#ifndef HAVE_STRNLEN
+/*
+ * Incredibly, libc5 doesn't appear to have strnlen. So we have to
+ * provide our own.
+ */
+static int my_strnlen(const char * s, int count)
+{
+ const char *cp = s;
+
+ while (count-- && *cp)
+ cp++;
+ return cp - s;
+}
+#define strnlen(str, x) my_strnlen((str),(x))
+#endif
+
errcode_t ext2fs_symlink(ext2_filsys fs, ext2_ino_t parent, ext2_ino_t ino,
const char *name, const char *target)
{
int fastlink, inlinelink;
unsigned int target_len;
char *block_buf = 0;
+ int drop_refcount = 0;
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
- /* The Linux kernel doesn't allow for links longer than a block */
+ /*
+ * The Linux kernel doesn't allow for links longer than a block
+ * (counting the NUL terminator)
+ */
target_len = strnlen(target, fs->blocksize + 1);
- if (target_len > fs->blocksize) {
+ if (target_len >= fs->blocksize) {
retval = EXT2_ET_INVALID_ARGUMENT;
goto cleanup;
}
/*
* Allocate a data block for slow links
*/
- retval = ext2fs_get_mem(fs->blocksize+1, &block_buf);
+ retval = ext2fs_get_mem(fs->blocksize, &block_buf);
if (retval)
goto cleanup;
- memset(block_buf, 0, fs->blocksize+1);
+ memset(block_buf, 0, fs->blocksize);
strncpy(block_buf, target, fs->blocksize);
memset(&inode, 0, sizeof(struct ext2_inode));
ext2fs_inode_size_set(fs, &inode, target_len);
/* The time fields are set by ext2fs_write_new_inode() */
- inlinelink = !fastlink &&
- ext2fs_has_feature_inline_data(fs->super) &&
- (target_len < fs->blocksize);
+ inlinelink = !fastlink && ext2fs_has_feature_inline_data(fs->super);
if (fastlink) {
/* Fast symlinks, target stored in inode */
strcpy((char *)&inode.i_block, target);
}
/*
+ * Update accounting....
+ */
+ if (!fastlink && !inlinelink)
+ ext2fs_block_alloc_stats2(fs, blk, +1);
+ ext2fs_inode_alloc_stats2(fs, ino, +1, 0);
+ drop_refcount = 1;
+
+ /*
* Link the symlink into the filesystem hierarchy
*/
if (name) {
if (retval)
goto cleanup;
}
-
- /*
- * Update accounting....
- */
- if (!fastlink && !inlinelink)
- ext2fs_block_alloc_stats2(fs, blk, +1);
- ext2fs_inode_alloc_stats2(fs, ino, +1, 0);
+ drop_refcount = 0;
cleanup:
if (block_buf)
ext2fs_free_mem(&block_buf);
+ if (drop_refcount) {
+ if (!fastlink && !inlinelink)
+ ext2fs_block_alloc_stats2(fs, blk, -1);
+ ext2fs_inode_alloc_stats2(fs, ino, -1, 0);
+ }
return retval;
}
+
+/*
+ * Test whether an inode is a fast symlink.
+ *
+ * A fast symlink has its symlink data stored in inode->i_block.
+ */
+int ext2fs_is_fast_symlink(struct ext2_inode *inode)
+{
+ return LINUX_S_ISLNK(inode->i_mode) && EXT2_I_SIZE(inode) &&
+ EXT2_I_SIZE(inode) < sizeof(inode->i_block);
+}