file operation wrapping

Data Structures
struct	lws_fop_fd
struct	lws_fops_index
struct	lws_plat_file_ops

Typedefs
typedef struct lws_fop_fd *	lws_fop_fd_t

Functions
LWS_VISIBLE LWS_EXTERN struct lws_plat_file_ops *LWS_WARN_UNUSED_RESULT	lws_get_fops (struct lws_context *context)
LWS_VISIBLE LWS_EXTERN void	lws_set_fops (struct lws_context *context, const struct lws_plat_file_ops *fops)
LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT	lws_vfs_tell (lws_fop_fd_t fop_fd)
LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT	lws_vfs_get_length (lws_fop_fd_t fop_fd)
LWS_VISIBLE LWS_EXTERN uint32_t LWS_WARN_UNUSED_RESULT	lws_vfs_get_mod_time (lws_fop_fd_t fop_fd)
LWS_VISIBLE LWS_EXTERN lws_fileofs_t	lws_vfs_file_seek_set (lws_fop_fd_t fop_fd, lws_fileofs_t offset)
LWS_VISIBLE LWS_EXTERN lws_fileofs_t	lws_vfs_file_seek_end (lws_fop_fd_t fop_fd, lws_fileofs_t offset)
LWS_VISIBLE LWS_EXTERN lws_fop_fd_t LWS_WARN_UNUSED_RESULT	lws_vfs_file_open (const struct lws_plat_file_ops *fops, const char *vfs_path, lws_fop_flags_t *flags)
LWS_VISIBLE LWS_EXTERN lws_fop_fd_t	_lws_plat_file_open (const struct lws_plat_file_ops *fops, const char *filename, const char *vpath, lws_fop_flags_t *flags)
LWS_VISIBLE LWS_EXTERN int	_lws_plat_file_close (lws_fop_fd_t *fop_fd)
LWS_VISIBLE LWS_EXTERN lws_fileofs_t	_lws_plat_file_seek_cur (lws_fop_fd_t fop_fd, lws_fileofs_t offset)
LWS_VISIBLE LWS_EXTERN int	_lws_plat_file_read (lws_fop_fd_t fop_fd, lws_filepos_t *amount, uint8_t *buf, lws_filepos_t len)
LWS_VISIBLE LWS_EXTERN int	_lws_plat_file_write (lws_fop_fd_t fop_fd, lws_filepos_t *amount, uint8_t *buf, lws_filepos_t len)
LWS_VISIBLE LWS_EXTERN int	lws_alloc_vfs_file (struct lws_context *context, const char *filename, uint8_t **buf, lws_filepos_t *amount)

Variables
struct lws_plat_file_ops	fops_zip

Detailed Description

File operation wrapping

Use these helper functions if you want to access a file from the perspective of a specific wsi, which is usually the case. If you just want contextless file access, use the fops callbacks directly with NULL wsi instead of these helpers.

If so, then it calls the platform handler or user overrides where present (as defined in info->fops)

The advantage from all this is user code can be portable for file operations without having to deal with differences between platforms.

Function Documentation

lws_get_fops()

LWS_VISIBLE LWS_EXTERN struct lws_plat_file_ops* LWS_WARN_UNUSED_RESULT lws_get_fops

(

struct lws_context *

context

)

#include <lib/libwebsockets.h>

lws_get_fops() - get current file ops

Parameters

context

context

lws_vfs_file_open()

LWS_VISIBLE LWS_EXTERN lws_fop_fd_t LWS_WARN_UNUSED_RESULT lws_vfs_file_open	(	const struct lws_plat_file_ops *	fops,
		const char *	vfs_path,
		lws_fop_flags_t *	flags
	)

#include <lib/libwebsockets.h>

lws_plat_file_open() - open vfs filepath

Parameters

fops	file ops struct that applies to this descriptor
vfs_path	filename to open
flags	pointer to open flags

The vfs_path is scanned for known fops signatures, and the open directed to any matching fops open.

User code should use this api to perform vfs opens.

returns semi-opaque handle

lws_vfs_file_seek_end()

LWS_VISIBLE LWS_EXTERN lws_fileofs_t lws_vfs_file_seek_end	(	lws_fop_fd_t	fop_fd,
		lws_fileofs_t	offset
	)

#include <lib/libwebsockets.h>

lws_vfs_file_seek_end() - seek relative to end of file

Parameters

fop_fd	fop_fd we are seeking in
offset	offset from start of file

lws_vfs_file_seek_set()

LWS_VISIBLE LWS_EXTERN lws_fileofs_t lws_vfs_file_seek_set	(	lws_fop_fd_t	fop_fd,
		lws_fileofs_t	offset
	)

#include <lib/libwebsockets.h>

lws_vfs_file_seek_set() - seek relative to start of file

Parameters

fop_fd	fop_fd we are seeking in
offset	offset from start of file

lws_vfs_get_length()

LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT lws_vfs_get_length

(

lws_fop_fd_t

fop_fd

)

#include <lib/libwebsockets.h>

lws_vfs_get_length() - get current file total length in bytes

Parameters

fop_fd

fop_fd we are asking about

lws_vfs_get_mod_time()

LWS_VISIBLE LWS_EXTERN uint32_t LWS_WARN_UNUSED_RESULT lws_vfs_get_mod_time

(

lws_fop_fd_t

fop_fd

)

#include <lib/libwebsockets.h>

lws_vfs_get_mod_time() - get time file last modified

Parameters

fop_fd

fop_fd we are asking about

lws_vfs_tell()

LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT lws_vfs_tell

(

lws_fop_fd_t

fop_fd

)

#include <lib/libwebsockets.h>

lws_vfs_tell() - get current file position

Parameters

fop_fd

fop_fd we are asking about