X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=lib%2Fofpbuf.h;h=8008cb47fe36a3d3611e1fd1b360a5ca772f6209;hb=HEAD;hp=34fcf5f7f956430e753a633ea4a9c118983a98cf;hpb=7ecb095d0bf4940406ce684c5c6d5c7adac4cf77;p=cascardo%2Fovs.git diff --git a/lib/ofpbuf.h b/lib/ofpbuf.h index 34fcf5f7f..8008cb47f 100644 --- a/lib/ofpbuf.h +++ b/lib/ofpbuf.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2015, 2016 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -20,42 +20,94 @@ #include #include #include "list.h" +#include "packets.h" #include "util.h" #ifdef __cplusplus extern "C" { #endif -enum ofpbuf_source { +enum OVS_PACKED_ENUM ofpbuf_source { OFPBUF_MALLOC, /* Obtained via malloc(). */ - OFPBUF_STACK /* Stack space or static buffer. */ + OFPBUF_STACK, /* Un-movable stack space or static buffer. */ + OFPBUF_STUB, /* Starts on stack, may expand into heap. */ }; /* Buffer for holding arbitrary data. An ofpbuf is automatically reallocated - * as necessary if it grows too large for the available memory. */ + * as necessary if it grows too large for the available memory. + * + * 'header' and 'msg' conventions: + * + * OpenFlow messages: 'header' points to the start of the OpenFlow + * header, while 'msg' is the OpenFlow msg body. + * When parsing, the 'data' will move past these, as data is being + * pulled from the OpenFlow message. + * + * Caution: buffer manipulation of 'struct ofpbuf' must always update + * the 'header' and 'msg' pointers. + * + * + * Actions: When encoding OVS action lists, the 'header' is used + * as a pointer to the beginning of the current action (see ofpact_put()). + * + * rconn: Reuses 'header' as a private pointer while queuing. + */ struct ofpbuf { void *base; /* First byte of allocated space. */ - size_t allocated; /* Number of bytes allocated. */ - enum ofpbuf_source source; /* Source of memory allocated as 'base'. */ - void *data; /* First byte actually in use. */ - size_t size; /* Number of bytes in use. */ - - void *l2; /* Link-level header. */ - void *l3; /* Network-level header. */ - void *l4; /* Transport-level header. */ - void *l7; /* Application data. */ + uint32_t size; /* Number of bytes in use. */ + uint32_t allocated; /* Number of bytes allocated. */ - struct list list_node; /* Private list element for use by owner. */ - void *private_p; /* Private pointer for use by owner. */ + void *header; /* OpenFlow header. */ + void *msg; /* message's body */ + struct ovs_list list_node; /* Private list element for use by owner. */ + enum ofpbuf_source source; /* Source of memory allocated as 'base'. */ }; -/* Declares NAME as a SIZE-byte array aligned properly for storing any kind of - * data. For use with ofpbuf_use_stack(). */ -#define OFPBUF_STACK_BUFFER(NAME, SIZE) uint64_t NAME[DIV_ROUND_UP(SIZE, 8)] +/* An initializer for a struct ofpbuf that will be initially empty and uses the + * space in STUB (which should be an array) as a stub. This is the initializer + * form of ofpbuf_use_stub(). + * + * Usage example: + * + * uint64_t stub[1024 / 8]; // 1 kB stub properly aligned for 64-bit data. + * struct ofpbuf ofpbuf = OFPBUF_STUB_INITIALIZER(stub); + */ +#define OFPBUF_STUB_INITIALIZER(STUB) { \ + .base = (STUB), \ + .data = (STUB), \ + .size = 0, \ + .allocated = sizeof (STUB), \ + .header = NULL, \ + .msg = NULL, \ + .list_node = OVS_LIST_POISON, \ + .source = OFPBUF_STUB, \ + } -void ofpbuf_use(struct ofpbuf *, void *, size_t); +/* An initializer for a struct ofpbuf whose data starts at DATA and continues + * for SIZE bytes. This is appropriate for an ofpbuf that will be used to + * inspect existing data, without moving it around or reallocating it, and + * generally without modifying it at all. This is the initializer form of + * ofpbuf_use_const(). + */ +static inline struct ofpbuf +ofpbuf_const_initializer(const void *data, size_t size) +{ + return (struct ofpbuf) { + .base = CONST_CAST(void *, data), + .data = CONST_CAST(void *, data), + .size = size, + .allocated = size, + .header = NULL, + .msg = NULL, + .list_node = OVS_LIST_POISON, + .source = OFPBUF_STACK, + }; +} + +void ofpbuf_use_ds(struct ofpbuf *, const struct ds *); void ofpbuf_use_stack(struct ofpbuf *, void *, size_t); +void ofpbuf_use_stub(struct ofpbuf *, void *, size_t); void ofpbuf_use_const(struct ofpbuf *, const void *, size_t); void ofpbuf_init(struct ofpbuf *, size_t); @@ -70,12 +122,14 @@ struct ofpbuf *ofpbuf_clone_with_headroom(const struct ofpbuf *, struct ofpbuf *ofpbuf_clone_data(const void *, size_t); struct ofpbuf *ofpbuf_clone_data_with_headroom(const void *, size_t, size_t headroom); -void ofpbuf_delete(struct ofpbuf *); +static inline void ofpbuf_delete(struct ofpbuf *); -void *ofpbuf_at(const struct ofpbuf *, size_t offset, size_t size); -void *ofpbuf_at_assert(const struct ofpbuf *, size_t offset, size_t size); -void *ofpbuf_tail(const struct ofpbuf *); -void *ofpbuf_end(const struct ofpbuf *); +static inline void *ofpbuf_at(const struct ofpbuf *, size_t offset, + size_t size); +static inline void *ofpbuf_at_assert(const struct ofpbuf *, size_t offset, + size_t size); +static inline void *ofpbuf_tail(const struct ofpbuf *); +static inline void *ofpbuf_end(const struct ofpbuf *); void *ofpbuf_put_uninit(struct ofpbuf *, size_t); void *ofpbuf_put_zeros(struct ofpbuf *, size_t); @@ -86,25 +140,133 @@ void *ofpbuf_push_uninit(struct ofpbuf *b, size_t); void *ofpbuf_push_zeros(struct ofpbuf *, size_t); void *ofpbuf_push(struct ofpbuf *b, const void *, size_t); -size_t ofpbuf_headroom(const struct ofpbuf *); -size_t ofpbuf_tailroom(const struct ofpbuf *); +static inline size_t ofpbuf_headroom(const struct ofpbuf *); +static inline size_t ofpbuf_tailroom(const struct ofpbuf *); +static inline size_t ofpbuf_msgsize(const struct ofpbuf *); void ofpbuf_prealloc_headroom(struct ofpbuf *, size_t); void ofpbuf_prealloc_tailroom(struct ofpbuf *, size_t); void ofpbuf_trim(struct ofpbuf *); +void ofpbuf_padto(struct ofpbuf *, size_t); +void ofpbuf_shift(struct ofpbuf *, int); -void ofpbuf_clear(struct ofpbuf *); -void *ofpbuf_pull(struct ofpbuf *, size_t); -void *ofpbuf_try_pull(struct ofpbuf *, size_t); +static inline void ofpbuf_clear(struct ofpbuf *); +static inline void *ofpbuf_pull(struct ofpbuf *, size_t); +static inline void *ofpbuf_try_pull(struct ofpbuf *, size_t); void *ofpbuf_steal_data(struct ofpbuf *); char *ofpbuf_to_string(const struct ofpbuf *, size_t maxbytes); +static inline struct ofpbuf *ofpbuf_from_list(const struct ovs_list *); +void ofpbuf_list_delete(struct ovs_list *); +static inline bool ofpbuf_equal(const struct ofpbuf *, const struct ofpbuf *); + + +/* Frees memory that 'b' points to, as well as 'b' itself. */ +static inline void ofpbuf_delete(struct ofpbuf *b) +{ + if (b) { + ofpbuf_uninit(b); + free(b); + } +} + +/* If 'b' contains at least 'offset + size' bytes of data, returns a pointer to + * byte 'offset'. Otherwise, returns a null pointer. */ +static inline void *ofpbuf_at(const struct ofpbuf *b, size_t offset, + size_t size) +{ + return offset + size <= b->size ? (char *) b->data + offset : NULL; +} -static inline struct ofpbuf *ofpbuf_from_list(const struct list *list) +/* Returns a pointer to byte 'offset' in 'b', which must contain at least + * 'offset + size' bytes of data. */ +static inline void *ofpbuf_at_assert(const struct ofpbuf *b, size_t offset, + size_t size) +{ + ovs_assert(offset + size <= b->size); + return ((char *) b->data) + offset; +} + +/* Returns a pointer to byte following the last byte of data in use in 'b'. */ +static inline void *ofpbuf_tail(const struct ofpbuf *b) +{ + return (char *) b->data + b->size; +} + +/* Returns a pointer to byte following the last byte allocated for use (but + * not necessarily in use) in 'b'. */ +static inline void *ofpbuf_end(const struct ofpbuf *b) +{ + return (char *) b->base + b->allocated; +} + +/* Returns the number of bytes of headroom in 'b', that is, the number of bytes + * of unused space in ofpbuf 'b' before the data that is in use. (Most + * commonly, the data in a ofpbuf is at its beginning, and thus the ofpbuf's + * headroom is 0.) */ +static inline size_t ofpbuf_headroom(const struct ofpbuf *b) +{ + return (char*)b->data - (char*)b->base; +} + +/* Returns the number of bytes that may be appended to the tail end of ofpbuf + * 'b' before the ofpbuf must be reallocated. */ +static inline size_t ofpbuf_tailroom(const struct ofpbuf *b) +{ + return (char*)ofpbuf_end(b) - (char*)ofpbuf_tail(b); +} + +/* Returns the number of bytes from 'b->header' to 'b->msg', that is, the + * length of 'b''s header. */ +static inline size_t +ofpbuf_headersize(const struct ofpbuf *b) +{ + return (char *)b->msg - (char *)b->header; +} + +/* Returns the number of bytes from 'b->msg' to 'b->data + b->size', that is, + * the length of the used space in 'b' starting from 'msg'. */ +static inline size_t +ofpbuf_msgsize(const struct ofpbuf *b) +{ + return (char *)ofpbuf_tail(b) - (char *)b->msg; +} + +/* Clears any data from 'b'. */ +static inline void ofpbuf_clear(struct ofpbuf *b) +{ + b->data = b->base; + b->size = 0; +} + +/* Removes 'size' bytes from the head end of 'b', which must contain at least + * 'size' bytes of data. Returns the first byte of data removed. */ +static inline void *ofpbuf_pull(struct ofpbuf *b, size_t size) +{ + void *data = b->data; + b->data = (char*)b->data + size; + b->size = b->size - size; + return data; +} + +/* If 'b' has at least 'size' bytes of data, removes that many bytes from the + * head end of 'b' and returns the first byte removed. Otherwise, returns a + * null pointer without modifying 'b'. */ +static inline void *ofpbuf_try_pull(struct ofpbuf *b, size_t size) +{ + return b->size >= size ? ofpbuf_pull(b, size) : NULL; +} + +static inline struct ofpbuf *ofpbuf_from_list(const struct ovs_list *list) { return CONTAINER_OF(list, struct ofpbuf, list_node); } -void ofpbuf_list_delete(struct list *); + +static inline bool ofpbuf_equal(const struct ofpbuf *a, const struct ofpbuf *b) +{ + return a->size == b->size && + memcmp(a->data, b->data, a->size) == 0; +} #ifdef __cplusplus }