X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=lib%2Fofpbuf.c;h=02c9d15f82bfaffec64e7312b5fc274a5453d3b5;hb=c391558c30d7d7eb5c20da3ba0cd4700b6890962;hp=8166d6b1c1a1f3ee29ed361fbae3afc9ef1690be;hpb=7ecb095d0bf4940406ce684c5c6d5c7adac4cf77;p=cascardo%2Fovs.git diff --git a/lib/ofpbuf.c b/lib/ofpbuf.c index 8166d6b1c..02c9d15f8 100644 --- a/lib/ofpbuf.c +++ b/lib/ofpbuf.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 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. @@ -16,52 +16,91 @@ #include #include "ofpbuf.h" -#include #include #include #include "dynamic-string.h" +#include "netdev-dpdk.h" #include "util.h" static void -ofpbuf_use__(struct ofpbuf *b, void *base, size_t allocated, - enum ofpbuf_source source) +ofpbuf_init__(struct ofpbuf *b, size_t allocated, enum ofpbuf_source source) { - b->base = b->data = base; b->allocated = allocated; b->source = source; - b->size = 0; - b->l2 = b->l3 = b->l4 = b->l7 = NULL; + b->header = NULL; + b->msg = NULL; list_poison(&b->list_node); - b->private_p = NULL; +} + +static void +ofpbuf_use__(struct ofpbuf *b, void *base, size_t allocated, size_t size, + enum ofpbuf_source source) +{ + b->base = base; + b->data = base; + b->size = size; + + ofpbuf_init__(b, allocated, source); } /* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of * memory starting at 'base'. 'base' should be the first byte of a region * obtained from malloc(). It will be freed (with free()) if 'b' is resized or * freed. */ -void +static void ofpbuf_use(struct ofpbuf *b, void *base, size_t allocated) { - ofpbuf_use__(b, base, allocated, OFPBUF_MALLOC); + ofpbuf_use__(b, base, allocated, 0, OFPBUF_MALLOC); +} + +/* Converts ds into ofpbuf 'b'. 'b' contains the 'ds->allocated' bytes of + * memory starting at 'ds->string'. 'ds' should not be modified any more. + * The memory allocated for 'ds' will be freed (with free()) if 'b' is + * resized or freed. */ +void +ofpbuf_use_ds(struct ofpbuf *b, const struct ds *ds) +{ + ofpbuf_use__(b, ds->string, ds->allocated + 1, ds->length, OFPBUF_MALLOC); } /* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of * memory starting at 'base'. 'base' should point to a buffer on the stack. - * - * An ofpbuf operation that requires reallocating data will assert-fail if this - * function was used to initialize it. + * (Nothing actually relies on 'base' being allocated on the stack. It could + * be static or malloc()'d memory. But stack space is the most common use + * case.) * * 'base' should be appropriately aligned. Using an array of uint32_t or * uint64_t for the buffer is a reasonable way to ensure appropriate alignment * for 32- or 64-bit data. * + * An ofpbuf operation that requires reallocating data will assert-fail if this + * function was used to initialize it. Thus, one need not call ofpbuf_uninit() + * on an ofpbuf initialized by this function (though doing so is harmless), + * because it is guaranteed that 'b' does not own any heap-allocated memory. */ +void +ofpbuf_use_stack(struct ofpbuf *b, void *base, size_t allocated) +{ + ofpbuf_use__(b, base, allocated, 0, OFPBUF_STACK); +} + +/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of + * memory starting at 'base'. 'base' should point to a buffer on the stack. * (Nothing actually relies on 'base' being allocated on the stack. It could * be static or malloc()'d memory. But stack space is the most common use - * case.) */ + * case.) + * + * 'base' should be appropriately aligned. Using an array of uint32_t or + * uint64_t for the buffer is a reasonable way to ensure appropriate alignment + * for 32- or 64-bit data. + * + * An ofpbuf operation that requires reallocating data will copy the provided + * buffer into a malloc()'d buffer. Thus, it is wise to call ofpbuf_uninit() + * on an ofpbuf initialized by this function, so that if it expanded into the + * heap, that memory is freed. */ void -ofpbuf_use_stack(struct ofpbuf *b, void *base, size_t allocated) +ofpbuf_use_stub(struct ofpbuf *b, void *base, size_t allocated) { - ofpbuf_use__(b, base, allocated, OFPBUF_STACK); + ofpbuf_use__(b, base, allocated, 0, OFPBUF_STUB); } /* Initializes 'b' as an ofpbuf whose data starts at 'data' and continues for @@ -74,8 +113,7 @@ ofpbuf_use_stack(struct ofpbuf *b, void *base, size_t allocated) void ofpbuf_use_const(struct ofpbuf *b, const void *data, size_t size) { - ofpbuf_use__(b, (void *) data, size, OFPBUF_STACK); - b->size = size; + ofpbuf_use__(b, CONST_CAST(void *, data), size, size, OFPBUF_STACK); } /* Initializes 'b' as an empty ofpbuf with an initial capacity of 'size' @@ -90,8 +128,10 @@ ofpbuf_init(struct ofpbuf *b, size_t size) void ofpbuf_uninit(struct ofpbuf *b) { - if (b && b->source == OFPBUF_MALLOC) { - free(b->base); + if (b) { + if (b->source == OFPBUF_MALLOC) { + free(b->base); + } } } @@ -129,7 +169,7 @@ ofpbuf_new_with_headroom(size_t size, size_t headroom) struct ofpbuf * ofpbuf_clone(const struct ofpbuf *buffer) { - return ofpbuf_clone_data(buffer->data, buffer->size); + return ofpbuf_clone_with_headroom(buffer, 0); } /* Creates and returns a new ofpbuf whose data are copied from 'buffer'. The @@ -137,8 +177,19 @@ ofpbuf_clone(const struct ofpbuf *buffer) struct ofpbuf * ofpbuf_clone_with_headroom(const struct ofpbuf *buffer, size_t headroom) { - return ofpbuf_clone_data_with_headroom(buffer->data, buffer->size, - headroom); + struct ofpbuf *new_buffer; + + new_buffer = ofpbuf_clone_data_with_headroom(buffer->data, + buffer->size, + headroom); + if (buffer->header) { + ptrdiff_t data_delta = (char *)new_buffer->data - (char *)buffer->data; + + new_buffer->header = (char *) buffer->header + data_delta; + } + new_buffer->msg = buffer->msg; + + return new_buffer; } /* Creates and returns a new ofpbuf that initially contains a copy of the @@ -160,34 +211,6 @@ ofpbuf_clone_data_with_headroom(const void *data, size_t size, size_t headroom) return b; } -/* Frees memory that 'b' points to, as well as 'b' itself. */ -void -ofpbuf_delete(struct ofpbuf *b) -{ - if (b) { - ofpbuf_uninit(b); - free(b); - } -} - -/* 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.) */ -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. */ -size_t -ofpbuf_tailroom(const struct ofpbuf *b) -{ - return (char*)ofpbuf_end(b) - (char*)ofpbuf_tail(b); -} - static void ofpbuf_copy__(struct ofpbuf *b, uint8_t *new_base, size_t new_headroom, size_t new_tailroom) @@ -225,10 +248,16 @@ ofpbuf_resize__(struct ofpbuf *b, size_t new_headroom, size_t new_tailroom) break; case OFPBUF_STACK: - NOT_REACHED(); + OVS_NOT_REACHED(); + + case OFPBUF_STUB: + b->source = OFPBUF_MALLOC; + new_base = xmalloc(new_allocated); + ofpbuf_copy__(b, new_base, new_headroom, new_tailroom); + break; default: - NOT_REACHED(); + OVS_NOT_REACHED(); } b->allocated = new_allocated; @@ -236,20 +265,17 @@ ofpbuf_resize__(struct ofpbuf *b, size_t new_headroom, size_t new_tailroom) new_data = (char *) new_base + new_headroom; if (b->data != new_data) { - uintptr_t data_delta = (char *) new_data - (char *) b->data; - b->data = new_data; - if (b->l2) { - b->l2 = (char *) b->l2 + data_delta; - } - if (b->l3) { - b->l3 = (char *) b->l3 + data_delta; - } - if (b->l4) { - b->l4 = (char *) b->l4 + data_delta; + if (b->header) { + ptrdiff_t data_delta = (char *) b->header - (char *) b->data; + + b->header = (char *) new_data + data_delta; } - if (b->l7) { - b->l7 = (char *) b->l7 + data_delta; + if (b->msg) { + ptrdiff_t data_delta = (char *) b->msg - (char *) b->data; + + b->msg = (char *) new_data + data_delta; } + b->data = new_data; } } @@ -275,11 +301,17 @@ ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size) } } -/* Trims the size of 'b' to fit its actual content, reducing its tailroom to - * 0. Its headroom, if any, is preserved. +/* Trims the size of 'b' to fit its actual content, reducing its headroom and + * tailroom to 0, if any. * * Buffers not obtained from malloc() are not resized, since that wouldn't save - * any memory. */ + * any memory. + * + * Caller needs to updates 'b->header' and 'b->msg' so that they point to the + * same locations in the data. (If they pointed into the tailroom or headroom + * then they become invalid.) + * + */ void ofpbuf_trim(struct ofpbuf *b) { @@ -289,6 +321,38 @@ ofpbuf_trim(struct ofpbuf *b) } } +/* If 'b' is shorter than 'length' bytes, pads its tail out with zeros to that + * length. */ +void +ofpbuf_padto(struct ofpbuf *b, size_t length) +{ + if (b->size < length) { + ofpbuf_put_zeros(b, length - b->size); + } +} + +/* Shifts all of the data within the allocated space in 'b' by 'delta' bytes. + * For example, a 'delta' of 1 would cause each byte of data to move one byte + * forward (from address 'p' to 'p+1'), and a 'delta' of -1 would cause each + * byte to move one byte backward (from 'p' to 'p-1'). + * + * If used, user must make sure the 'header' and 'msg' pointers are updated + * after shifting. + */ +void +ofpbuf_shift(struct ofpbuf *b, int delta) +{ + ovs_assert(delta > 0 ? delta <= ofpbuf_tailroom(b) + : delta < 0 ? -delta <= ofpbuf_headroom(b) + : true); + + if (delta != 0) { + char *dst = (char *) b->data + delta; + memmove(dst, b->data, b->size); + b->data = dst; + } +} + /* Appends 'size' bytes of data to the tail end of 'b', reallocating and * copying its data if necessary. Returns a pointer to the first byte of the * new data, which is left uninitialized. */ @@ -324,10 +388,10 @@ ofpbuf_put(struct ofpbuf *b, const void *p, size_t size) return dst; } -/* Parses as many pairs of hex digits as possible (possibly separated by - * spaces) from the beginning of 's', appending bytes for their values to 'b'. - * Returns the first character of 's' that is not the first of a pair of hex - * digits. If 'n' is nonnull, stores the number of bytes added to 'b' in +/* Parses as many pairs of hex digits as possible (possibly separated by spaces + * or periods) from the beginning of 's', appending bytes for their values to + * 'b'. Returns the first character of 's' that is not the first of a pair of + * hex digits. If 'n' is nonnull, stores the number of bytes added to 'b' in * '*n'. */ char * ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n) @@ -337,13 +401,13 @@ ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n) uint8_t byte; bool ok; - s += strspn(s, " "); + s += strspn(s, " .\t\r\n"); byte = hexits_value(s, 2, &ok); if (!ok) { if (n) { *n = b->size - initial_size; } - return (char *) s; + return CONST_CAST(char *, s); } ofpbuf_put(b, &byte, 1); @@ -356,7 +420,7 @@ ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n) void ofpbuf_reserve(struct ofpbuf *b, size_t size) { - assert(!b->size); + ovs_assert(!b->size); ofpbuf_prealloc_tailroom(b, size); b->data = (char*)b->data + size; } @@ -395,67 +459,6 @@ ofpbuf_push(struct ofpbuf *b, const void *p, size_t size) return dst; } -/* If 'b' contains at least 'offset + size' bytes of data, returns a pointer to - * byte 'offset'. Otherwise, returns a null pointer. */ -void * -ofpbuf_at(const struct ofpbuf *b, size_t offset, size_t size) -{ - return offset + size <= b->size ? (char *) b->data + offset : NULL; -} - -/* Returns a pointer to byte 'offset' in 'b', which must contain at least - * 'offset + size' bytes of data. */ -void * -ofpbuf_at_assert(const struct ofpbuf *b, size_t offset, size_t size) -{ - assert(offset + size <= b->size); - return ((char *) b->data) + offset; -} - -/* Returns the byte following the last byte of data in use in 'b'. */ -void * -ofpbuf_tail(const struct ofpbuf *b) -{ - return (char *) b->data + b->size; -} - -/* Returns the byte following the last byte allocated for use (but not - * necessarily in use) by 'b'. */ -void * -ofpbuf_end(const struct ofpbuf *b) -{ - return (char *) b->base + b->allocated; -} - -/* Clears any data from 'b'. */ -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. */ -void * -ofpbuf_pull(struct ofpbuf *b, size_t size) -{ - void *data = b->data; - assert(b->size >= size); - b->data = (char*)b->data + 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'. */ -void * -ofpbuf_try_pull(struct ofpbuf *b, size_t size) -{ - return b->size >= size ? ofpbuf_pull(b, size) : NULL; -} - /* Returns the data in 'b' as a block of malloc()'d memory and frees the buffer * within 'b'. (If 'b' itself was dynamically allocated, e.g. with * ofpbuf_new(), then it should still be freed with, e.g., ofpbuf_delete().) */ @@ -463,6 +466,7 @@ void * ofpbuf_steal_data(struct ofpbuf *b) { void *p; + if (b->source == OFPBUF_MALLOC && b->data == b->base) { p = b->data; } else { @@ -471,7 +475,10 @@ ofpbuf_steal_data(struct ofpbuf *b) free(b->base); } } - b->base = b->data = NULL; + b->base = NULL; + b->data = NULL; + b->header = NULL; + b->msg = NULL; return p; } @@ -483,7 +490,7 @@ ofpbuf_to_string(const struct ofpbuf *b, size_t maxbytes) struct ds s; ds_init(&s); - ds_put_format(&s, "size=%zu, allocated=%zu, head=%zu, tail=%zu\n", + ds_put_format(&s, "size=%"PRIu32", allocated=%"PRIu32", head=%"PRIuSIZE", tail=%"PRIuSIZE"\n", b->size, b->allocated, ofpbuf_headroom(b), ofpbuf_tailroom(b)); ds_put_hex_dump(&s, b->data, MIN(b->size, maxbytes), 0, false); @@ -493,12 +500,11 @@ ofpbuf_to_string(const struct ofpbuf *b, size_t maxbytes) /* Removes each of the "struct ofpbuf"s on 'list' from the list and frees * them. */ void -ofpbuf_list_delete(struct list *list) +ofpbuf_list_delete(struct ovs_list *list) { - struct ofpbuf *b, *next; + struct ofpbuf *b; - LIST_FOR_EACH_SAFE (b, next, list_node, list) { - list_remove(&b->list_node); + LIST_FOR_EACH_POP (b, list_node, list) { ofpbuf_delete(b); } }