libubox/blob.h
Felix Fietkau 77a629375d blob/blobmsg: add explicit typecasts for attribute iterators
Fixes C++ compatibility.

Reported in https://forum.lede-project.org/t/blobmsg-for-each-attr-from-c/389

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2016-11-29 14:02:57 +01:00

257 lines
6.6 KiB
C

/*
* blob - library for generating/parsing tagged binary data
*
* Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _BLOB_H__
#define _BLOB_H__
#include <stdbool.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include "utils.h"
#define BLOB_COOKIE 0x01234567
enum {
BLOB_ATTR_UNSPEC,
BLOB_ATTR_NESTED,
BLOB_ATTR_BINARY,
BLOB_ATTR_STRING,
BLOB_ATTR_INT8,
BLOB_ATTR_INT16,
BLOB_ATTR_INT32,
BLOB_ATTR_INT64,
BLOB_ATTR_LAST
};
#define BLOB_ATTR_ID_MASK 0x7f000000
#define BLOB_ATTR_ID_SHIFT 24
#define BLOB_ATTR_LEN_MASK 0x00ffffff
#define BLOB_ATTR_ALIGN 4
#define BLOB_ATTR_EXTENDED 0x80000000
struct blob_attr {
uint32_t id_len;
char data[];
} __packed;
struct blob_attr_info {
unsigned int type;
unsigned int minlen;
unsigned int maxlen;
bool (*validate)(const struct blob_attr_info *, struct blob_attr *);
};
struct blob_buf {
struct blob_attr *head;
bool (*grow)(struct blob_buf *buf, int minlen);
int buflen;
void *buf;
};
/*
* blob_data: returns the data pointer for an attribute
*/
static inline void *
blob_data(const struct blob_attr *attr)
{
return (void *) attr->data;
}
/*
* blob_id: returns the id of an attribute
*/
static inline unsigned int
blob_id(const struct blob_attr *attr)
{
int id = (be32_to_cpu(attr->id_len) & BLOB_ATTR_ID_MASK) >> BLOB_ATTR_ID_SHIFT;
return id;
}
static inline bool
blob_is_extended(const struct blob_attr *attr)
{
return !!(attr->id_len & cpu_to_be32(BLOB_ATTR_EXTENDED));
}
/*
* blob_len: returns the length of the attribute's payload
*/
static inline unsigned int
blob_len(const struct blob_attr *attr)
{
return (be32_to_cpu(attr->id_len) & BLOB_ATTR_LEN_MASK) - sizeof(struct blob_attr);
}
/*
* blob_raw_len: returns the complete length of an attribute (including the header)
*/
static inline unsigned int
blob_raw_len(const struct blob_attr *attr)
{
return blob_len(attr) + sizeof(struct blob_attr);
}
/*
* blob_pad_len: returns the padded length of an attribute (including the header)
*/
static inline unsigned int
blob_pad_len(const struct blob_attr *attr)
{
unsigned int len = blob_raw_len(attr);
len = (len + BLOB_ATTR_ALIGN - 1) & ~(BLOB_ATTR_ALIGN - 1);
return len;
}
static inline uint8_t
blob_get_u8(const struct blob_attr *attr)
{
return *((uint8_t *) attr->data);
}
static inline uint16_t
blob_get_u16(const struct blob_attr *attr)
{
uint16_t *tmp = (uint16_t*)attr->data;
return be16_to_cpu(*tmp);
}
static inline uint32_t
blob_get_u32(const struct blob_attr *attr)
{
uint32_t *tmp = (uint32_t*)attr->data;
return be32_to_cpu(*tmp);
}
static inline uint64_t
blob_get_u64(const struct blob_attr *attr)
{
uint32_t *ptr = (uint32_t *) blob_data(attr);
uint64_t tmp = ((uint64_t) be32_to_cpu(ptr[0])) << 32;
tmp |= be32_to_cpu(ptr[1]);
return tmp;
}
static inline int8_t
blob_get_int8(const struct blob_attr *attr)
{
return blob_get_u8(attr);
}
static inline int16_t
blob_get_int16(const struct blob_attr *attr)
{
return blob_get_u16(attr);
}
static inline int32_t
blob_get_int32(const struct blob_attr *attr)
{
return blob_get_u32(attr);
}
static inline int64_t
blob_get_int64(const struct blob_attr *attr)
{
return blob_get_u64(attr);
}
static inline const char *
blob_get_string(const struct blob_attr *attr)
{
return attr->data;
}
static inline struct blob_attr *
blob_next(const struct blob_attr *attr)
{
return (struct blob_attr *) ((char *) attr + blob_pad_len(attr));
}
extern void blob_fill_pad(struct blob_attr *attr);
extern void blob_set_raw_len(struct blob_attr *attr, unsigned int len);
extern bool blob_attr_equal(const struct blob_attr *a1, const struct blob_attr *a2);
extern int blob_buf_init(struct blob_buf *buf, int id);
extern void blob_buf_free(struct blob_buf *buf);
extern bool blob_buf_grow(struct blob_buf *buf, int required);
extern struct blob_attr *blob_new(struct blob_buf *buf, int id, int payload);
extern void *blob_nest_start(struct blob_buf *buf, int id);
extern void blob_nest_end(struct blob_buf *buf, void *cookie);
extern struct blob_attr *blob_put(struct blob_buf *buf, int id, const void *ptr, unsigned int len);
extern bool blob_check_type(const void *ptr, unsigned int len, int type);
extern int blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max);
extern struct blob_attr *blob_memdup(struct blob_attr *attr);
extern struct blob_attr *blob_put_raw(struct blob_buf *buf, const void *ptr, unsigned int len);
static inline struct blob_attr *
blob_put_string(struct blob_buf *buf, int id, const char *str)
{
return blob_put(buf, id, str, strlen(str) + 1);
}
static inline struct blob_attr *
blob_put_u8(struct blob_buf *buf, int id, uint8_t val)
{
return blob_put(buf, id, &val, sizeof(val));
}
static inline struct blob_attr *
blob_put_u16(struct blob_buf *buf, int id, uint16_t val)
{
val = cpu_to_be16(val);
return blob_put(buf, id, &val, sizeof(val));
}
static inline struct blob_attr *
blob_put_u32(struct blob_buf *buf, int id, uint32_t val)
{
val = cpu_to_be32(val);
return blob_put(buf, id, &val, sizeof(val));
}
static inline struct blob_attr *
blob_put_u64(struct blob_buf *buf, int id, uint64_t val)
{
val = cpu_to_be64(val);
return blob_put(buf, id, &val, sizeof(val));
}
#define blob_put_int8 blob_put_u8
#define blob_put_int16 blob_put_u16
#define blob_put_int32 blob_put_u32
#define blob_put_int64 blob_put_u64
#define __blob_for_each_attr(pos, attr, rem) \
for (pos = (struct blob_attr *) attr; \
rem > 0 && (blob_pad_len(pos) <= rem) && \
(blob_pad_len(pos) >= sizeof(struct blob_attr)); \
rem -= blob_pad_len(pos), pos = blob_next(pos))
#define blob_for_each_attr(pos, attr, rem) \
for (rem = attr ? blob_len(attr) : 0, \
pos = (struct blob_attr *) (attr ? blob_data(attr) : NULL); \
rem > 0 && (blob_pad_len(pos) <= rem) && \
(blob_pad_len(pos) >= sizeof(struct blob_attr)); \
rem -= blob_pad_len(pos), pos = blob_next(pos))
#endif