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/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010-2018 Andy Green <andy@warmcat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation:
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*
* included from libwebsockets.h
*/
/*! \defgroup fops file operation wrapping
*
* ##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.
*/
//@{
/** struct lws_plat_file_ops - Platform-specific file operations
*
* These provide platform-agnostic ways to deal with filesystem access in the
* library and in the user code.
*/
#if defined(LWS_WITH_ESP32)
/* sdk preprocessor defs? compiler issue? gets confused with member names */
#define LWS_FOP_OPEN _open
#define LWS_FOP_CLOSE _close
#define LWS_FOP_SEEK_CUR _seek_cur
#define LWS_FOP_READ _read
#define LWS_FOP_WRITE _write
#else
#define LWS_FOP_OPEN open
#define LWS_FOP_CLOSE close
#define LWS_FOP_SEEK_CUR seek_cur
#define LWS_FOP_READ read
#define LWS_FOP_WRITE write
#endif
#define LWS_FOP_FLAGS_MASK ((1 << 23) - 1)
#define LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP (1 << 24)
#define LWS_FOP_FLAG_COMPR_IS_GZIP (1 << 25)
#define LWS_FOP_FLAG_MOD_TIME_VALID (1 << 26)
#define LWS_FOP_FLAG_VIRTUAL (1 << 27)
struct lws_plat_file_ops;
struct lws_fop_fd {
lws_filefd_type fd;
/**< real file descriptor related to the file... */
const struct lws_plat_file_ops *fops;
/**< fops that apply to this fop_fd */
void *filesystem_priv;
/**< ignored by lws; owned by the fops handlers */
lws_filepos_t pos;
/**< generic "position in file" */
lws_filepos_t len;
/**< generic "length of file" */
lws_fop_flags_t flags;
/**< copy of the returned flags */
uint32_t mod_time;
/**< optional "modification time of file", only valid if .open()
* set the LWS_FOP_FLAG_MOD_TIME_VALID flag */
};
typedef struct lws_fop_fd *lws_fop_fd_t;
struct lws_fops_index {
const char *sig; /* NULL or vfs signature, eg, ".zip/" */
uint8_t len; /* length of above string */
};
struct lws_plat_file_ops {
lws_fop_fd_t (*LWS_FOP_OPEN)(const struct lws_plat_file_ops *fops,
const char *filename, const char *vpath,
lws_fop_flags_t *flags);
/**< Open file (always binary access if plat supports it)
* vpath may be NULL, or if the fops understands it, the point at which
* the filename's virtual part starts.
* *flags & LWS_FOP_FLAGS_MASK should be set to O_RDONLY or O_RDWR.
* If the file may be gzip-compressed,
* LWS_FOP_FLAG_COMPR_ACCEPTABLE_GZIP is set. If it actually is
* gzip-compressed, then the open handler should OR
* LWS_FOP_FLAG_COMPR_IS_GZIP on to *flags before returning.
*/
int (*LWS_FOP_CLOSE)(lws_fop_fd_t *fop_fd);
/**< close file AND set the pointer to NULL */
lws_fileofs_t (*LWS_FOP_SEEK_CUR)(lws_fop_fd_t fop_fd,
lws_fileofs_t offset_from_cur_pos);
/**< seek from current position */
int (*LWS_FOP_READ)(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
uint8_t *buf, lws_filepos_t len);
/**< Read from file, on exit *amount is set to amount actually read */
int (*LWS_FOP_WRITE)(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
uint8_t *buf, lws_filepos_t len);
/**< Write to file, on exit *amount is set to amount actually written */
struct lws_fops_index fi[3];
/**< vfs path signatures implying use of this fops */
const struct lws_plat_file_ops *next;
/**< NULL or next fops in list */
/* Add new things just above here ---^
* This is part of the ABI, don't needlessly break compatibility */
};
/**
* lws_get_fops() - get current file ops
*
* \param context: context
*/
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_vfs_tell() - get current file position
*
* \param fop_fd: fop_fd we are asking about
*/
LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT
lws_vfs_tell(lws_fop_fd_t fop_fd);
/**
* lws_vfs_get_length() - get current file total length in bytes
*
* \param fop_fd: fop_fd we are asking about
*/
LWS_VISIBLE LWS_EXTERN lws_filepos_t LWS_WARN_UNUSED_RESULT
lws_vfs_get_length(lws_fop_fd_t fop_fd);
/**
* lws_vfs_get_mod_time() - get time file last modified
*
* \param fop_fd: fop_fd we are asking about
*/
LWS_VISIBLE LWS_EXTERN uint32_t LWS_WARN_UNUSED_RESULT
lws_vfs_get_mod_time(lws_fop_fd_t fop_fd);
/**
* lws_vfs_file_seek_set() - seek relative to start of file
*
* \param fop_fd: fop_fd we are seeking in
* \param offset: offset from start of file
*/
LWS_VISIBLE LWS_EXTERN lws_fileofs_t
lws_vfs_file_seek_set(lws_fop_fd_t fop_fd, lws_fileofs_t offset);
/**
* lws_vfs_file_seek_end() - seek relative to end of file
*
* \param fop_fd: fop_fd we are seeking in
* \param offset: offset from start of file
*/
LWS_VISIBLE LWS_EXTERN lws_fileofs_t
lws_vfs_file_seek_end(lws_fop_fd_t fop_fd, lws_fileofs_t offset);
extern struct lws_plat_file_ops fops_zip;
/**
* lws_plat_file_open() - open vfs filepath
*
* \param fops: file ops struct that applies to this descriptor
* \param vfs_path: filename to open
* \param 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_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_plat_file_close() - close file
*
* \param fop_fd: file handle to close
*/
static LWS_INLINE int
lws_vfs_file_close(lws_fop_fd_t *fop_fd)
{
if (*fop_fd && (*fop_fd)->fops)
return (*fop_fd)->fops->LWS_FOP_CLOSE(fop_fd);
return 0;
}
/**
* lws_plat_file_seek_cur() - close file
*
*
* \param fop_fd: file handle
* \param offset: position to seek to
*/
static LWS_INLINE lws_fileofs_t
lws_vfs_file_seek_cur(lws_fop_fd_t fop_fd, lws_fileofs_t offset)
{
return fop_fd->fops->LWS_FOP_SEEK_CUR(fop_fd, offset);
}
/**
* lws_plat_file_read() - read from file
*
* \param fop_fd: file handle
* \param amount: how much to read (rewritten by call)
* \param buf: buffer to write to
* \param len: max length
*/
static LWS_INLINE int LWS_WARN_UNUSED_RESULT
lws_vfs_file_read(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
uint8_t *buf, lws_filepos_t len)
{
return fop_fd->fops->LWS_FOP_READ(fop_fd, amount, buf, len);
}
/**
* lws_plat_file_write() - write from file
*
* \param fop_fd: file handle
* \param amount: how much to write (rewritten by call)
* \param buf: buffer to read from
* \param len: max length
*/
static LWS_INLINE int LWS_WARN_UNUSED_RESULT
lws_vfs_file_write(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
uint8_t *buf, lws_filepos_t len)
{
return fop_fd->fops->LWS_FOP_WRITE(fop_fd, amount, buf, len);
}
/* these are the platform file operations implementations... they can
* be called directly and used in fops arrays
*/
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);
//@}
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