[mirror_frr.git] / lib / stream.h

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Packet interface
 * Copyright (C) 1999 Kunihiro Ishiguro
 */

#ifndef _ZEBRA_STREAM_H
#define _ZEBRA_STREAM_H

#include <pthread.h>

#include "frratomic.h"
#include "mpls.h"
#include "prefix.h"

#ifdef __cplusplus
extern "C" {
#endif

/*
 * A stream is an arbitrary buffer, whose contents generally are assumed to
 * be in network order.
 *
 * A stream has the following attributes associated with it:
 *
 * - size: the allocated, invariant size of the buffer.
 *
 * - getp: the get position marker, denoting the offset in the stream where
 *         the next read (or 'get') will be from. This getp marker is
 *         automatically adjusted when data is read from the stream, the
 *         user may also manipulate this offset as they wish, within limits
 *         (see below)
 *
 * - endp: the end position marker, denoting the offset in the stream where
 *         valid data ends, and if the user attempted to write (or
 *         'put') data where that data would be written (or 'put') to.
 *
 * These attributes are all size_t values.
 *
 * Constraints:
 *
 * 1. getp can never exceed endp
 *
 * - hence if getp is equal to endp, there is no more valid data that can be
 *   gotten from the stream (though, the user may reposition getp to earlier in
 *   the stream, if they wish).
 *
 * 2. endp can never exceed size
 *
 * - hence, if endp is equal to size, then the stream is full, and no more
 *   data can be written to the stream.
 *
 * In other words the following must always be true, and the stream
 * abstraction is allowed internally to assert that the following property
 * holds true for a stream, as and when it wishes:
 *
 *        getp <= endp <= size
 *
 * It is the users responsibility to ensure this property is never violated.
 *
 * A stream therefore can be thought of like this:
 *
 * 	---------------------------------------------------
 * 	|XXXXXXXXXXXXXXXXXXXXXXXX                         |
 * 	---------------------------------------------------
 *               ^               ^                        ^
 *               getp            endp                     size
 *
 * This shows a stream containing data (shown as 'X') up to the endp offset.
 * The stream is empty from endp to size. Without adjusting getp, there are
 * still endp-getp bytes of valid data to be read from the stream.
 *
 * Methods are provided to get and put to/from the stream, as well as
 * retrieve the values of the 3 markers and manipulate the getp marker.
 *
 * Note:
 * At the moment, newly allocated streams are zero filled. Hence, one can
 * use stream_forward_endp() to effectively create arbitrary zero-fill
 * padding. However, note that stream_reset() does *not* zero-out the
 * stream. This property should **not** be relied upon.
 *
 * Best practice is to use stream_put (<stream *>, NULL, <size>) to zero out
 * any part of a stream which isn't otherwise written to.
 */

/* Stream buffer. */
struct stream {
	struct stream *next;

	/*
	 * Remainder is ***private*** to stream
	 * direct access is frowned upon!
	 * Use the appropriate functions/macros
	 */
	size_t getp;	       /* next get position */
	size_t endp;	       /* last valid data position */
	size_t size;	       /* size of data segment */
	unsigned char data[];  /* data pointer */
};

/* First in first out queue structure. */
struct stream_fifo {
	/* lock for mt-safe operations */
	pthread_mutex_t mtx;

	/* number of streams in this fifo */
	atomic_size_t count;
#if defined DEV_BUILD
	atomic_size_t max_count;
#endif

	struct stream *head;
	struct stream *tail;
};

/* Utility macros. */
#define STREAM_SIZE(S)  ((S)->size)
/* number of bytes which can still be written */
#define STREAM_WRITEABLE(S) ((S)->size - (S)->endp)
/* number of bytes still to be read */
#define STREAM_READABLE(S) ((S)->endp - (S)->getp)

#define STREAM_CONCAT_REMAIN(S1, S2, size) ((size) - (S1)->endp - (S2)->endp)

/* this macro is deprecated, but not slated for removal anytime soon */
#define STREAM_DATA(S)  ((S)->data)

/* Stream prototypes.
 * For stream_{put,get}S, the S suffix mean:
 *
 * c: character (unsigned byte)
 * w: word (two bytes)
 * l: long (two words)
 * q: quad (four words)
 */
extern struct stream *stream_new(size_t);
extern void stream_free(struct stream *);
/* Copy 'src' into 'dest', returns 'dest' */
extern struct stream *stream_copy(struct stream *dest,
				  const struct stream *src);
extern struct stream *stream_dup(const struct stream *s);

extern size_t stream_resize_inplace(struct stream **sptr, size_t newsize);

extern size_t stream_get_getp(const struct stream *s);
extern size_t stream_get_endp(const struct stream *s);
extern size_t stream_get_size(const struct stream *s);

/**
 * Create a new stream structure; copy offset bytes from s1 to the new
 * stream; copy s2 data to the new stream; copy rest of s1 data to the
 * new stream.
 */
extern struct stream *stream_dupcat(const struct stream *s1,
				    const struct stream *s2, size_t offset);

extern void stream_set_getp(struct stream *, size_t);
extern void stream_set_endp(struct stream *, size_t);
extern void stream_forward_getp(struct stream *, size_t);
extern bool stream_forward_getp2(struct stream *, size_t);
extern void stream_rewind_getp(struct stream *s, size_t size);
extern bool stream_rewind_getp2(struct stream *s, size_t size);
extern void stream_forward_endp(struct stream *, size_t);
extern bool stream_forward_endp2(struct stream *, size_t);

/* steam_put: NULL source zeroes out size_t bytes of stream */
extern void stream_put(struct stream *, const void *, size_t);
extern int stream_putc(struct stream *, uint8_t);
extern int stream_putc_at(struct stream *, size_t, uint8_t);
extern int stream_putw(struct stream *, uint16_t);
extern int stream_putw_at(struct stream *, size_t, uint16_t);
extern int stream_put3(struct stream *, uint32_t);
extern int stream_put3_at(struct stream *, size_t, uint32_t);
extern int stream_putl(struct stream *, uint32_t);
extern int stream_putl_at(struct stream *, size_t, uint32_t);
extern int stream_putq(struct stream *, uint64_t);
extern int stream_putq_at(struct stream *, size_t, uint64_t);
extern int stream_put_ipv4(struct stream *, uint32_t);
extern int stream_put_in_addr(struct stream *s, const struct in_addr *addr);
extern bool stream_put_ipaddr(struct stream *s, struct ipaddr *ip);
extern int stream_put_in_addr_at(struct stream *s, size_t putp,
				 const struct in_addr *addr);
extern int stream_put_in6_addr_at(struct stream *s, size_t putp,
				  const struct in6_addr *addr);
extern int stream_put_prefix_addpath(struct stream *s, const struct prefix *p,
				     bool addpath_capable,
				     uint32_t addpath_tx_id);
extern int stream_put_prefix(struct stream *s, const struct prefix *p);
extern int stream_put_labeled_prefix(struct stream *, const struct prefix *,
				     mpls_label_t *, bool addpath_capable,
				     uint32_t addpath_tx_id);
extern void stream_get(void *, struct stream *, size_t);
extern bool stream_get2(void *data, struct stream *s, size_t size);
extern void stream_get_from(void *, struct stream *, size_t, size_t);
extern uint8_t stream_getc(struct stream *);
extern bool stream_getc2(struct stream *s, uint8_t *byte);
extern uint8_t stream_getc_from(struct stream *, size_t);
extern uint16_t stream_getw(struct stream *);
extern bool stream_getw2(struct stream *s, uint16_t *word);
extern uint16_t stream_getw_from(struct stream *, size_t);
extern uint32_t stream_get3(struct stream *);
extern uint32_t stream_get3_from(struct stream *, size_t);
extern uint32_t stream_getl(struct stream *);
extern bool stream_getl2(struct stream *s, uint32_t *l);
extern uint32_t stream_getl_from(struct stream *, size_t);
extern uint64_t stream_getq(struct stream *);
extern uint64_t stream_getq_from(struct stream *, size_t);
bool stream_getq2(struct stream *s, uint64_t *q);
extern uint32_t stream_get_ipv4(struct stream *);
extern bool stream_get_ipaddr(struct stream *s, struct ipaddr *ip);

/* IEEE-754 floats */
extern float stream_getf(struct stream *);
extern double stream_getd(struct stream *);
extern int stream_putf(struct stream *, float);
extern int stream_putd(struct stream *, double);

#undef stream_read
#undef stream_write

/* Deprecated: assumes blocking I/O.  Will be removed.
   Use stream_read_try instead.  */
extern int stream_read(struct stream *, int, size_t);

/* Read up to size bytes into the stream.
   Return code:
     >0: number of bytes read
     0: end-of-file
     -1: fatal error
     -2: transient error, should retry later (i.e. EAGAIN or EINTR)
   This is suitable for use with non-blocking file descriptors.
 */
extern ssize_t stream_read_try(struct stream *s, int fd, size_t size);

extern ssize_t stream_recvmsg(struct stream *s, int fd, struct msghdr *,
			      int flags, size_t size);
extern ssize_t stream_recvfrom(struct stream *s, int fd, size_t len, int flags,
			       struct sockaddr *from, socklen_t *fromlen);
extern size_t stream_write(struct stream *, const void *, size_t);

/* reset the stream. See Note above */
extern void stream_reset(struct stream *);
extern int stream_flush(struct stream *, int);
extern int stream_empty(struct stream *); /* is the stream empty? */

/* debugging */
extern void stream_hexdump(const struct stream *s);

/**
 * Reorganize the buffer data so it can fit more. This function is normally
 * called right after stream data is consumed so we can read more data
 * (the functions that consume data start with `stream_get*()` and macros
 * `STREAM_GET*()`).
 *
 * \param s stream pointer.
 */
extern void stream_pulldown(struct stream *s);

/* deprecated */
extern uint8_t *stream_pnt(struct stream *);

/*
 * Operations on struct stream_fifo.
 *
 * Each function has a safe variant, which ensures that the operation performed
 * is atomic with respect to the operations performed by all other safe
 * variants. In other words, the safe variants lock the stream_fifo's mutex
 * before performing their action. These are provided for convenience when
 * using stream_fifo in a multithreaded context, to alleviate the need for the
 * caller to implement their own synchronization around the stream_fifo.
 *
 * The following functions do not have safe variants. The caller must ensure
 * that these operations are performed safely in a multithreaded context:
 * - stream_fifo_new
 * - stream_fifo_free
 */

/*
 * Create a new stream_fifo.
 *
 * Returns:
 *    newly created stream_fifo
 */
extern struct stream_fifo *stream_fifo_new(void);

/*
 * Init or re-init an on-stack fifo. This allows use of a fifo struct without
 * requiring a malloc/free cycle.
 * Note well that the fifo must be de-inited with the 'fifo_deinit' api.
 */
void stream_fifo_init(struct stream_fifo *fifo);

/*
 * Deinit an on-stack fifo.
 */
void stream_fifo_deinit(struct stream_fifo *fifo);

/*
 * Push a stream onto a stream_fifo.
 *
 * fifo
 *    the stream_fifo to push onto
 *
 * s
 *    the stream to push onto the stream_fifo
 */
extern void stream_fifo_push(struct stream_fifo *fifo, struct stream *s);
extern void stream_fifo_push_safe(struct stream_fifo *fifo, struct stream *s);

/*
 * Pop a stream off a stream_fifo.
 *
 * fifo
 *    the stream_fifo to pop from
 *
 * Returns:
 *    the next stream in the stream_fifo
 */
extern struct stream *stream_fifo_pop(struct stream_fifo *fifo);
extern struct stream *stream_fifo_pop_safe(struct stream_fifo *fifo);

/*
 * Retrieve the next stream from a stream_fifo without popping it.
 *
 * fifo
 *    the stream_fifo to operate on
 *
 * Returns:
 *    the next stream that would be returned from stream_fifo_pop
 */
extern struct stream *stream_fifo_head(struct stream_fifo *fifo);
extern struct stream *stream_fifo_head_safe(struct stream_fifo *fifo);

/*
 * Remove all streams from a stream_fifo.
 *
 * fifo
 *    the stream_fifo to clean
 */
extern void stream_fifo_clean(struct stream_fifo *fifo);
extern void stream_fifo_clean_safe(struct stream_fifo *fifo);

/*
 * Retrieve number of streams on a stream_fifo.
 *
 * fifo
 *    the stream_fifo to retrieve the count for
 *
 * Returns:
 *    the number of streams on the stream_fifo
 */
extern size_t stream_fifo_count_safe(struct stream_fifo *fifo);

/*
 * Free a stream_fifo.
 *
 * Calls stream_fifo_clean, then deinitializes the stream_fifo and frees it.
 *
 * fifo
 *    the stream_fifo to free
 */
extern void stream_fifo_free(struct stream_fifo *fifo);

/* This is here because "<< 24" is particularly problematic in C.
 * This is because the left operand of << is integer-promoted, which means
 * an uint8_t gets converted into a *signed* int.  Shifting into the sign
 * bit of a signed int is theoretically undefined behaviour, so - the left
 * operand needs to be cast to unsigned.
 *
 * This is not a problem for 16- or 8-bit values (they don't reach the sign
 * bit), for 64-bit values (you need to cast them anyway), and neither for
 * encoding (because it's downcasted.)
 */
static inline const uint8_t *ptr_get_be64(const uint8_t *ptr, uint64_t *out)
{
	uint32_t tmp1, tmp2;

	memcpy(&tmp1, ptr, sizeof(tmp1));
	memcpy(&tmp2, ptr + sizeof(tmp1), sizeof(tmp1));

	*out = (((uint64_t)ntohl(tmp1)) << 32) | ntohl(tmp2);

	return ptr + 8;
}

static inline const uint8_t *ptr_get_be32(const uint8_t *ptr, uint32_t *out)
{
	uint32_t tmp;

	memcpy(&tmp, ptr, sizeof(tmp));
	*out = ntohl(tmp);
	return ptr + 4;
}

static inline uint8_t *ptr_get_be16(uint8_t *ptr, uint16_t *out)
{
	uint16_t tmp;

	memcpy(&tmp, ptr, sizeof(tmp));
	*out = ntohs(tmp);

	return ptr + 2;
}

/*
 * so Normal stream_getX functions assert.  Which is anathema
 * to keeping a daemon up and running when something goes south
 * Provide a stream_getX2 functions that do not assert.
 * In addition provide these macro's that upon failure
 * goto stream_failure.  This is modeled upon some NL_XX
 * macros in the linux kernel.
 *
 * This change allows for proper memory freeing
 * after we've detected an error.
 *
 * In the future we will be removing the assert in
 * the stream functions but we need a transition
 * plan.
 */
#define STREAM_GETC(S, P)                                                      \
	do {                                                                   \
		uint8_t _pval;                                                 \
		if (!stream_getc2((S), &_pval))                                \
			goto stream_failure;                                   \
		(P) = _pval;                                                   \
	} while (0)

#define STREAM_GETW(S, P)                                                      \
	do {                                                                   \
		uint16_t _pval;                                                \
		if (!stream_getw2((S), &_pval))                                \
			goto stream_failure;                                   \
		(P) = _pval;                                                   \
	} while (0)

#define STREAM_GETL(S, P)                                                      \
	do {                                                                   \
		uint32_t _pval;                                                \
		if (!stream_getl2((S), &_pval))                                \
			goto stream_failure;                                   \
		(P) = _pval;                                                   \
	} while (0)

#define STREAM_GETF(S, P)                                                      \
	do {                                                                   \
		union {                                                        \
			float r;                                               \
			uint32_t d;                                            \
		} _pval;                                                       \
		if (!stream_getl2((S), &_pval.d))                              \
			goto stream_failure;                                   \
		(P) = _pval.r;                                                 \
	} while (0)

#define STREAM_GETQ(S, P)                                                      \
	do {                                                                   \
		uint64_t _pval;                                                \
		if (!stream_getq2((S), &_pval))                                \
			goto stream_failure;                                   \
		(P) = _pval;                                                   \
	} while (0)

#define STREAM_GET_IPADDR(S, P)                                                \
	do {                                                                   \
		if (!stream_get_ipaddr((S), (P)))                              \
			goto stream_failure;                                   \
	} while (0)

#define STREAM_GET(P, STR, SIZE)                                               \
	do {                                                                   \
		if (!stream_get2((P), (STR), (SIZE)))                          \
			goto stream_failure;                                   \
	} while (0)

#define STREAM_FORWARD_GETP(STR, SIZE)                                         \
	do {                                                                   \
		if (!stream_forward_getp2((STR), (SIZE)))                      \
			goto stream_failure;                                   \
	} while (0)

#define STREAM_REWIND_GETP(STR, SIZE)                                          \
	do {                                                                   \
		if (!stream_rewind_getp2((STR), (SIZE)))                       \
			goto stream_failure;                                   \
	} while (0)

#define STREAM_FORWARD_ENDP(STR, SIZE)                                         \
	do {                                                                   \
		if (!stream_forward_endp2((STR), (SIZE)))                      \
			goto stream_failure;                                   \
	} while (0)

#ifdef __cplusplus
}
#endif

#endif /* _ZEBRA_STREAM_H */
Commit	Line	Data
acddc0ed	1	// SPDX-License-Identifier: GPL-2.0-or-later
718e3744	2	/*
	3	* Packet interface
	4	* Copyright (C) 1999 Kunihiro Ishiguro
718e3744	5	*/
	6
	7	#ifndef _ZEBRA_STREAM_H
	8	#define _ZEBRA_STREAM_H
	9
363e24c6 QY	10	#include <pthread.h>
	11
	12	#include "frratomic.h"
9bedbb1e	13	#include "mpls.h"
02ff83c5	14	#include "prefix.h"
02ff83c5	15
5e244469 RW	16	#ifdef __cplusplus
	17	extern "C" {
	18	#endif
	19
050c013a	20	/*
	21	* A stream is an arbitrary buffer, whose contents generally are assumed to
	22	* be in network order.
	23	*
	24	* A stream has the following attributes associated with it:
	25	*
	26	* - size: the allocated, invariant size of the buffer.
	27	*
	28	* - getp: the get position marker, denoting the offset in the stream where
	29	* the next read (or 'get') will be from. This getp marker is
	30	* automatically adjusted when data is read from the stream, the
	31	* user may also manipulate this offset as they wish, within limits
	32	* (see below)
	33	*
	34	* - endp: the end position marker, denoting the offset in the stream where
	35	* valid data ends, and if the user attempted to write (or
	36	* 'put') data where that data would be written (or 'put') to.
	37	*
	38	* These attributes are all size_t values.
	39	*
	40	* Constraints:
	41	*
	42	* 1. getp can never exceed endp
	43	*
	44	* - hence if getp is equal to endp, there is no more valid data that can be
	45	* gotten from the stream (though, the user may reposition getp to earlier in
	46	* the stream, if they wish).
	47	*
	48	* 2. endp can never exceed size
	49	*
	50	* - hence, if endp is equal to size, then the stream is full, and no more
	51	* data can be written to the stream.
	52	*
	53	* In other words the following must always be true, and the stream
	54	* abstraction is allowed internally to assert that the following property
	55	* holds true for a stream, as and when it wishes:
	56	*
	57	* getp <= endp <= size
	58	*
	59	* It is the users responsibility to ensure this property is never violated.
	60	*
	61	* A stream therefore can be thought of like this:
	62	*
	63	* ---------------------------------------------------
	64	* \|XXXXXXXXXXXXXXXXXXXXXXXX \|
	65	* ---------------------------------------------------
	66	* ^ ^ ^
	67	* getp endp size
	68	*
	69	* This shows a stream containing data (shown as 'X') up to the endp offset.
	70	* The stream is empty from endp to size. Without adjusting getp, there are
	71	* still endp-getp bytes of valid data to be read from the stream.
	72	*
d62a17ae	73	* Methods are provided to get and put to/from the stream, as well as
050c013a	74	* retrieve the values of the 3 markers and manipulate the getp marker.
	75	*
	76	* Note:
	77	* At the moment, newly allocated streams are zero filled. Hence, one can
	78	* use stream_forward_endp() to effectively create arbitrary zero-fill
	79	* padding. However, note that stream_reset() does not zero-out the
	80	* stream. This property should not be relied upon.
0dab9303	81	*
	82	* Best practice is to use stream_put (<stream *>, NULL, <size>) to zero out
	83	* any part of a stream which isn't otherwise written to.
050c013a	84	*/
050c013a	85
718e3744	86	/* Stream buffer. */
d62a17ae	87	struct stream {
	88	struct stream *next;
	89
de75223e DS	90	/*
de75223e DS	91	* Remainder is *private* to stream
d62a17ae	92	* direct access is frowned upon!
	93	* Use the appropriate functions/macros
	94	*/
de75223e DS	95	size_t getp; /* next get position */
	96	size_t endp; /* last valid data position */
	97	size_t size; /* size of data segment */
83e7e1d7	98	unsigned char data[]; /* data pointer */
718e3744	99	};
	100
	101	/* First in first out queue structure. */
d62a17ae	102	struct stream_fifo {
363e24c6 QY	103	/* lock for mt-safe operations */
	104	pthread_mutex_t mtx;
	105
	106	/* number of streams in this fifo */
c8a65463	107	atomic_size_t count;
03ed85a6	108	#if defined DEV_BUILD
c8a65463	109	atomic_size_t max_count;
03ed85a6	110	#endif
718e3744	111
d62a17ae	112	struct stream *head;
d62a17ae	113	struct stream *tail;
718e3744	114	};
	115
	116	/* Utility macros. */
718e3744	117	#define STREAM_SIZE(S) ((S)->size)
d62a17ae	118	/* number of bytes which can still be written */
050c013a	119	#define STREAM_WRITEABLE(S) ((S)->size - (S)->endp)
d62a17ae	120	/* number of bytes still to be read */
050c013a	121	#define STREAM_READABLE(S) ((S)->endp - (S)->getp)
050c013a	122
d62a17ae	123	#define STREAM_CONCAT_REMAIN(S1, S2, size) ((size) - (S1)->endp - (S2)->endp)
8c71e481	124
2d34fb80 QY	125	/* this macro is deprecated, but not slated for removal anytime soon */
	126	#define STREAM_DATA(S) ((S)->data)
	127
d62a17ae	128	/* Stream prototypes.
4b201d46	129	* For stream_{put,get}S, the S suffix mean:
	130	*
	131	* c: character (unsigned byte)
	132	* w: word (two bytes)
	133	* l: long (two words)
	134	* q: quad (four words)
	135	*/
d62a17ae	136	extern struct stream *stream_new(size_t);
d62a17ae	137	extern void stream_free(struct stream *);
f8c511cd MS	138	/* Copy 'src' into 'dest', returns 'dest' */
	139	extern struct stream stream_copy(struct stream dest,
	140	const struct stream *src);
	141	extern struct stream stream_dup(const struct stream s);
43888669	142
43888669 DS	143	extern size_t stream_resize_inplace(struct stream **sptr, size_t newsize);
43888669 DS	144
f8c511cd MS	145	extern size_t stream_get_getp(const struct stream *s);
	146	extern size_t stream_get_endp(const struct stream *s);
	147	extern size_t stream_get_size(const struct stream *s);
8cc4198f	148
8c71e481 PM	149	/**
	150	* Create a new stream structure; copy offset bytes from s1 to the new
	151	* stream; copy s2 data to the new stream; copy rest of s1 data to the
	152	* new stream.
	153	*/
f8c511cd MS	154	extern struct stream stream_dupcat(const struct stream s1,
f8c511cd MS	155	const struct stream *s2, size_t offset);
8c71e481	156
d62a17ae	157	extern void stream_set_getp(struct stream *, size_t);
	158	extern void stream_set_endp(struct stream *, size_t);
	159	extern void stream_forward_getp(struct stream *, size_t);
4adddf0a	160	extern bool stream_forward_getp2(struct stream *, size_t);
06cf2c0c QY	161	extern void stream_rewind_getp(struct stream *s, size_t size);
06cf2c0c QY	162	extern bool stream_rewind_getp2(struct stream *s, size_t size);
d62a17ae	163	extern void stream_forward_endp(struct stream *, size_t);
4adddf0a	164	extern bool stream_forward_endp2(struct stream *, size_t);
8cc4198f	165
8cc4198f	166	/* steam_put: NULL source zeroes out size_t bytes of stream */
d62a17ae	167	extern void stream_put(struct stream , const void , size_t);
d7c0a89a QY	168	extern int stream_putc(struct stream *, uint8_t);
	169	extern int stream_putc_at(struct stream *, size_t, uint8_t);
	170	extern int stream_putw(struct stream *, uint16_t);
	171	extern int stream_putw_at(struct stream *, size_t, uint16_t);
	172	extern int stream_put3(struct stream *, uint32_t);
	173	extern int stream_put3_at(struct stream *, size_t, uint32_t);
	174	extern int stream_putl(struct stream *, uint32_t);
	175	extern int stream_putl_at(struct stream *, size_t, uint32_t);
d62a17ae	176	extern int stream_putq(struct stream *, uint64_t);
d62a17ae	177	extern int stream_putq_at(struct stream *, size_t, uint64_t);
d7c0a89a	178	extern int stream_put_ipv4(struct stream *, uint32_t);
d3d77ec4	179	extern int stream_put_in_addr(struct stream s, const struct in_addr addr);
31f937fb	180	extern bool stream_put_ipaddr(struct stream s, struct ipaddr ip);
d3d77ec4 MS	181	extern int stream_put_in_addr_at(struct stream *s, size_t putp,
	182	const struct in_addr *addr);
	183	extern int stream_put_in6_addr_at(struct stream *s, size_t putp,
	184	const struct in6_addr *addr);
be92fc9f DA	185	extern int stream_put_prefix_addpath(struct stream s, const struct prefix p,
be92fc9f DA	186	bool addpath_capable,
d7c0a89a	187	uint32_t addpath_tx_id);
d3d77ec4	188	extern int stream_put_prefix(struct stream s, const struct prefix p);
5f040085	189	extern int stream_put_labeled_prefix(struct stream , const struct prefix ,
be92fc9f	190	mpls_label_t *, bool addpath_capable,
ec15e1b5	191	uint32_t addpath_tx_id);
d62a17ae	192	extern void stream_get(void , struct stream , size_t);
051cc28c	193	extern bool stream_get2(void data, struct stream s, size_t size);
d62a17ae	194	extern void stream_get_from(void , struct stream , size_t, size_t);
d7c0a89a QY	195	extern uint8_t stream_getc(struct stream *);
	196	extern bool stream_getc2(struct stream s, uint8_t byte);
	197	extern uint8_t stream_getc_from(struct stream *, size_t);
	198	extern uint16_t stream_getw(struct stream *);
051cc28c	199	extern bool stream_getw2(struct stream s, uint16_t word);
d7c0a89a QY	200	extern uint16_t stream_getw_from(struct stream *, size_t);
	201	extern uint32_t stream_get3(struct stream *);
	202	extern uint32_t stream_get3_from(struct stream *, size_t);
	203	extern uint32_t stream_getl(struct stream *);
051cc28c	204	extern bool stream_getl2(struct stream s, uint32_t l);
d7c0a89a	205	extern uint32_t stream_getl_from(struct stream *, size_t);
d62a17ae	206	extern uint64_t stream_getq(struct stream *);
d62a17ae	207	extern uint64_t stream_getq_from(struct stream *, size_t);
c2b5a4e5	208	bool stream_getq2(struct stream s, uint64_t q);
d7c0a89a	209	extern uint32_t stream_get_ipv4(struct stream *);
31f937fb	210	extern bool stream_get_ipaddr(struct stream s, struct ipaddr ip);
718e3744	211
16f1b9ee	212	/* IEEE-754 floats */
d62a17ae	213	extern float stream_getf(struct stream *);
	214	extern double stream_getd(struct stream *);
	215	extern int stream_putf(struct stream *, float);
	216	extern int stream_putd(struct stream *, double);
16f1b9ee	217
718e3744	218	#undef stream_read
718e3744	219	#undef stream_write
262feb1a	220
d62a17ae	221	/* Deprecated: assumes blocking I/O. Will be removed.
262feb1a	222	Use stream_read_try instead. */
d62a17ae	223	extern int stream_read(struct stream *, int, size_t);
262feb1a	224
262feb1a	225	/* Read up to size bytes into the stream.
	226	Return code:
	227	>0: number of bytes read
	228	0: end-of-file
	229	-1: fatal error
	230	-2: transient error, should retry later (i.e. EAGAIN or EINTR)
	231	This is suitable for use with non-blocking file descriptors.
	232	*/
	233	extern ssize_t stream_read_try(struct stream *s, int fd, size_t size);
	234
d62a17ae	235	extern ssize_t stream_recvmsg(struct stream s, int fd, struct msghdr ,
	236	int flags, size_t size);
	237	extern ssize_t stream_recvfrom(struct stream *s, int fd, size_t len, int flags,
	238	struct sockaddr from, socklen_t fromlen);
	239	extern size_t stream_write(struct stream , const void , size_t);
718e3744	240
8cc4198f	241	/* reset the stream. See Note above */
d62a17ae	242	extern void stream_reset(struct stream *);
	243	extern int stream_flush(struct stream *, int);
	244	extern int stream_empty(struct stream ); / is the stream empty? */
050c013a	245
9d72660d	246	/* debugging */
f1bc75da	247	extern void stream_hexdump(const struct stream *s);
9d72660d	248
91804f63 RZ	249	/**
	250	* Reorganize the buffer data so it can fit more. This function is normally
	251	* called right after stream data is consumed so we can read more data
	252	* (the functions that consume data start with `stream_get*()` and macros
	253	* `STREAM_GET*()`).
	254	*
	255	* \param s stream pointer.
	256	*/
	257	extern void stream_pulldown(struct stream *s);
	258
050c013a	259	/* deprecated */
d7c0a89a	260	extern uint8_t stream_pnt(struct stream );
718e3744	261
363e24c6 QY	262	/*
	263	* Operations on struct stream_fifo.
	264	*
	265	* Each function has a safe variant, which ensures that the operation performed
	266	* is atomic with respect to the operations performed by all other safe
	267	* variants. In other words, the safe variants lock the stream_fifo's mutex
	268	* before performing their action. These are provided for convenience when
	269	* using stream_fifo in a multithreaded context, to alleviate the need for the
	270	* caller to implement their own synchronization around the stream_fifo.
	271	*
	272	* The following functions do not have safe variants. The caller must ensure
	273	* that these operations are performed safely in a multithreaded context:
	274	* - stream_fifo_new
	275	* - stream_fifo_free
	276	*/
	277
	278	/*
	279	* Create a new stream_fifo.
	280	*
	281	* Returns:
	282	* newly created stream_fifo
	283	*/
d62a17ae	284	extern struct stream_fifo *stream_fifo_new(void);
363e24c6	285
f8c511cd MS	286	/*
	287	* Init or re-init an on-stack fifo. This allows use of a fifo struct without
	288	* requiring a malloc/free cycle.
	289	* Note well that the fifo must be de-inited with the 'fifo_deinit' api.
	290	*/
	291	void stream_fifo_init(struct stream_fifo *fifo);
	292
	293	/*
	294	* Deinit an on-stack fifo.
	295	*/
	296	void stream_fifo_deinit(struct stream_fifo *fifo);
	297
363e24c6 QY	298	/*
	299	* Push a stream onto a stream_fifo.
	300	*
	301	* fifo
	302	* the stream_fifo to push onto
	303	*
	304	* s
	305	* the stream to push onto the stream_fifo
	306	*/
d62a17ae	307	extern void stream_fifo_push(struct stream_fifo fifo, struct stream s);
363e24c6 QY	308	extern void stream_fifo_push_safe(struct stream_fifo fifo, struct stream s);
	309
	310	/*
	311	* Pop a stream off a stream_fifo.
	312	*
	313	* fifo
	314	* the stream_fifo to pop from
	315	*
	316	* Returns:
	317	* the next stream in the stream_fifo
	318	*/
d62a17ae	319	extern struct stream stream_fifo_pop(struct stream_fifo fifo);
363e24c6 QY	320	extern struct stream stream_fifo_pop_safe(struct stream_fifo fifo);
	321
	322	/*
	323	* Retrieve the next stream from a stream_fifo without popping it.
	324	*
	325	* fifo
	326	* the stream_fifo to operate on
	327	*
	328	* Returns:
	329	* the next stream that would be returned from stream_fifo_pop
	330	*/
d62a17ae	331	extern struct stream stream_fifo_head(struct stream_fifo fifo);
363e24c6 QY	332	extern struct stream stream_fifo_head_safe(struct stream_fifo fifo);
	333
	334	/*
	335	* Remove all streams from a stream_fifo.
	336	*
	337	* fifo
	338	* the stream_fifo to clean
	339	*/
d62a17ae	340	extern void stream_fifo_clean(struct stream_fifo *fifo);
363e24c6 QY	341	extern void stream_fifo_clean_safe(struct stream_fifo *fifo);
	342
	343	/*
	344	* Retrieve number of streams on a stream_fifo.
	345	*
	346	* fifo
	347	* the stream_fifo to retrieve the count for
	348	*
	349	* Returns:
	350	* the number of streams on the stream_fifo
	351	*/
	352	extern size_t stream_fifo_count_safe(struct stream_fifo *fifo);
	353
	354	/*
	355	* Free a stream_fifo.
	356	*
	357	* Calls stream_fifo_clean, then deinitializes the stream_fifo and frees it.
	358	*
	359	* fifo
	360	* the stream_fifo to free
	361	*/
d62a17ae	362	extern void stream_fifo_free(struct stream_fifo *fifo);
718e3744	363
937652c6 DL	364	/* This is here because "<< 24" is particularly problematic in C.
	365	* This is because the left operand of << is integer-promoted, which means
	366	* an uint8_t gets converted into a signed int. Shifting into the sign
	367	* bit of a signed int is theoretically undefined behaviour, so - the left
	368	* operand needs to be cast to unsigned.
	369	*
	370	* This is not a problem for 16- or 8-bit values (they don't reach the sign
	371	* bit), for 64-bit values (you need to cast them anyway), and neither for
	372	* encoding (because it's downcasted.)
	373	*/
0c969118 DA	374	static inline const uint8_t ptr_get_be64(const uint8_t ptr, uint64_t *out)
	375	{
	376	uint32_t tmp1, tmp2;
	377
	378	memcpy(&tmp1, ptr, sizeof(tmp1));
	379	memcpy(&tmp2, ptr + sizeof(tmp1), sizeof(tmp1));
	380
	381	*out = (((uint64_t)ntohl(tmp1)) << 32) \| ntohl(tmp2);
	382
	383	return ptr + 8;
	384	}
	385
1be1693e	386	static inline const uint8_t ptr_get_be32(const uint8_t ptr, uint32_t *out)
937652c6 DL	387	{
937652c6 DL	388	uint32_t tmp;
1be1693e	389
937652c6 DL	390	memcpy(&tmp, ptr, sizeof(tmp));
	391	*out = ntohl(tmp);
	392	return ptr + 4;
	393	}
	394
74e2bd89 AK	395	static inline uint8_t ptr_get_be16(uint8_t ptr, uint16_t *out)
	396	{
	397	uint16_t tmp;
	398
	399	memcpy(&tmp, ptr, sizeof(tmp));
	400	*out = ntohs(tmp);
	401
	402	return ptr + 2;
	403	}
	404
051cc28c DS	405	/*
	406	* so Normal stream_getX functions assert. Which is anathema
	407	* to keeping a daemon up and running when something goes south
	408	* Provide a stream_getX2 functions that do not assert.
	409	* In addition provide these macro's that upon failure
	410	* goto stream_failure. This is modeled upon some NL_XX
	411	* macros in the linux kernel.
	412	*
	413	* This change allows for proper memory freeing
	414	* after we've detected an error.
	415	*
	416	* In the future we will be removing the assert in
	417	* the stream functions but we need a transition
	418	* plan.
	419	*/
996c9314 LB	420	#define STREAM_GETC(S, P) \
	421	do { \
	422	uint8_t _pval; \
	423	if (!stream_getc2((S), &_pval)) \
	424	goto stream_failure; \
	425	(P) = _pval; \
051cc28c DS	426	} while (0)
051cc28c DS	427
996c9314 LB	428	#define STREAM_GETW(S, P) \
	429	do { \
	430	uint16_t _pval; \
	431	if (!stream_getw2((S), &_pval)) \
	432	goto stream_failure; \
	433	(P) = _pval; \
051cc28c DS	434	} while (0)
051cc28c DS	435
996c9314 LB	436	#define STREAM_GETL(S, P) \
	437	do { \
	438	uint32_t _pval; \
	439	if (!stream_getl2((S), &_pval)) \
	440	goto stream_failure; \
	441	(P) = _pval; \
051cc28c DS	442	} while (0)
051cc28c DS	443
c2b5a4e5 QY	444	#define STREAM_GETF(S, P) \
	445	do { \
	446	union { \
	447	float r; \
	448	uint32_t d; \
	449	} _pval; \
741b1c4f	450	if (!stream_getl2((S), &_pval.d)) \
c2b5a4e5 QY	451	goto stream_failure; \
	452	(P) = _pval.r; \
	453	} while (0)
	454
	455	#define STREAM_GETQ(S, P) \
	456	do { \
	457	uint64_t _pval; \
	458	if (!stream_getq2((S), &_pval)) \
	459	goto stream_failure; \
	460	(P) = _pval; \
	461	} while (0)
	462
31f937fb SM	463	#define STREAM_GET_IPADDR(S, P) \
	464	do { \
	465	if (!stream_get_ipaddr((S), (P))) \
	466	goto stream_failure; \
	467	} while (0)
	468
996c9314 LB	469	#define STREAM_GET(P, STR, SIZE) \
	470	do { \
	471	if (!stream_get2((P), (STR), (SIZE))) \
	472	goto stream_failure; \
051cc28c DS	473	} while (0)
051cc28c DS	474
4adddf0a QY	475	#define STREAM_FORWARD_GETP(STR, SIZE) \
	476	do { \
	477	if (!stream_forward_getp2((STR), (SIZE))) \
	478	goto stream_failure; \
	479	} while (0)
	480
06cf2c0c QY	481	#define STREAM_REWIND_GETP(STR, SIZE) \
	482	do { \
	483	if (!stream_rewind_getp2((STR), (SIZE))) \
	484	goto stream_failure; \
	485	} while (0)
	486
4adddf0a QY	487	#define STREAM_FORWARD_ENDP(STR, SIZE) \
	488	do { \
	489	if (!stream_forward_endp2((STR), (SIZE))) \
	490	goto stream_failure; \
	491	} while (0)
	492
5e244469 RW	493	#ifdef __cplusplus
	494	}
	495	#endif
	496
718e3744	497	#endif /* _ZEBRA_STREAM_H */