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#include "inc.h"
static char getdents_buf[GETDENTS_BUFSIZ];
ssize_t fs_read(ino_t ino_nr, struct fsdriver_data *data, size_t bytes,
off_t pos, int __unused call)
{
size_t off, chunk, block_size, cum_io;
off_t f_size;
struct inode *i_node;
struct buf *bp;
int r;
/* Try to get inode according to its index. */
if ((i_node = get_inode(ino_nr)) == NULL)
return EINVAL; /* No inode found. */
f_size = i_node->i_stat.st_size;
if (pos >= f_size)
return 0; /* EOF */
/* Limit the request to the remainder of the file size. */
if ((off_t)bytes > f_size - pos)
bytes = (size_t)(f_size - pos);
block_size = v_pri.logical_block_size_l;
cum_io = 0;
r = OK;
/* Split the transfer into chunks that don't span two blocks. */
while (bytes > 0) {
off = pos % block_size;
chunk = block_size - off;
if (chunk > bytes)
chunk = bytes;
/* Read 'chunk' bytes. */
bp = read_extent_block(&i_node->extent, pos);
if (bp == NULL)
panic("bp not valid in rw_chunk; this can't happen");
r = fsdriver_copyout(data, cum_io, b_data(bp)+off, chunk);
lmfs_put_block(bp);
if (r != OK)
break;
/* Update counters and pointers. */
bytes -= chunk; /* Bytes yet to be read. */
cum_io += chunk; /* Bytes read so far. */
pos += chunk; /* Position within the file. */
}
return (r == OK) ? cum_io : r;
}
ssize_t fs_getdents(ino_t ino_nr, struct fsdriver_data *data, size_t bytes,
off_t *pos)
{
struct fsdriver_dentry fsdentry;
struct inode *i_node;
off_t cur_pos;
int r, len;
char *cp;
if ((i_node = get_inode(ino_nr)) == NULL)
return EINVAL;
if (*pos < 0 || *pos > SSIZE_MAX)
return EINVAL;
r = read_directory(i_node);
if (r != OK)
return r;
fsdriver_dentry_init(&fsdentry, data, bytes, getdents_buf,
sizeof(getdents_buf));
r = OK;
for (cur_pos = *pos; cur_pos < i_node->dir_size; cur_pos++) {
/* Compute the length of the name */
cp = memchr(i_node->dir_contents[cur_pos].name, '\0', NAME_MAX);
if (cp == NULL)
len = NAME_MAX;
else
len = cp - i_node->dir_contents[cur_pos].name;
r = fsdriver_dentry_add(&fsdentry,
i_node->dir_contents[cur_pos].i_node->i_stat.st_ino,
i_node->dir_contents[cur_pos].name, len,
IFTODT(i_node->dir_contents[cur_pos].i_node->i_stat.st_mode));
if (r <= 0)
break;
}
if (r >= 0 && (r = fsdriver_dentry_finish(&fsdentry)) >= 0)
*pos = cur_pos;
return r;
}
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