int file_seek(int fd, off_t pos, int whence)
{
struct stat __stat, *stat = &__stat;
int ret;
struct file *file;
if ((ret = fd2file(fd, &file)) != 0) {
return ret;
}
filemap_acquire(file);
switch (whence) {
case LSEEK_SET:
break;
case LSEEK_CUR:
pos += file->pos;
break;
case LSEEK_END:
if ((ret = vop_fstat(file->node, stat)) == 0) {
pos += stat->st_size;
}
break;
default:
ret = -E_INVAL;
}
if (ret == 0) {
if ((ret = vop_tryseek(file->node, pos)) == 0) {
file->pos = pos;
}
}
filemap_release(file);
return ret;
}
int file_fstat(int fd, struct stat *stat)
{
int ret;
struct file *file;
if ((ret = fd2file(fd, &file)) != 0) {
return ret;
}
filemap_acquire(file);
ret = vop_fstat(file->node, stat);
filemap_release(file);
return ret;
}
int file_open(char *path, uint32_t open_flags)
{
bool readable = 0, writable = 0;
switch (open_flags & O_ACCMODE) {
case O_RDONLY:
readable = 1;
break;
case O_WRONLY:
writable = 1;
break;
case O_RDWR:
readable = writable = 1;
break;
default:
return -E_INVAL;
}
int ret;
struct file *file;
if ((ret = filemap_alloc(NO_FD, &file)) != 0) {
return ret;
}
struct inode *node;
if ((ret = vfs_open(path, open_flags, &node)) != 0) {
filemap_free(file);
return ret;
}
file->pos = 0;
if (open_flags & O_APPEND) {
struct stat __stat, *stat = &__stat;
if ((ret = vop_fstat(node, stat)) != 0) {
vfs_close(node);
filemap_free(file);
return ret;
}
file->pos = stat->st_size;
}
file->node = node;
file->readable = readable;
file->writable = writable;
filemap_open(file);
return file->fd;
}
int file_open(char *path, uint32_t open_flags)
{
bool readable = 0, writable = 0;
switch (open_flags & O_ACCMODE) {
case O_RDONLY:
readable = 1;
break;
case O_WRONLY:
writable = 1;
break;
case O_RDWR:
readable = writable = 1;
break;
default:
return -E_INVAL;
}
//TODO: Implement other open flags.
//Try to allocate a new kernel struct file object.
struct file *file = kernel_file_pool_allocate();
file_init(file);
if(file == NULL) {
return -E_NO_MEM;
}
file->readable = readable;
file->writable = writable;
//Allocate a new file descriptor
struct file_desc_table *desc_table = fs_get_desc_table(current->fs_struct);
int fd = file_desc_table_get_unused(desc_table);
if(fd < 0) {
return -E_MFILE;
}
int ret;
//Allocate a new inode for the kernel file
struct inode *node;
ret = vfs_open(path, open_flags, &node);
if (ret != 0) {
kernel_file_pool_free(file);
return ret;
}
//Initialize file state
file->pos = 0;
if (open_flags & O_APPEND) {
struct stat __stat, *stat = &__stat;
if ((ret = vop_fstat(node, stat)) != 0) {
vfs_close(node);
kernel_file_pool_free(file);
return ret;
}
file->pos = stat->st_size;
}
//Associate the file descriptor with kernel file object
file_desc_table_associate(desc_table, fd, file);
file->node = node;
file->io_flags = 0;
return fd;
}
