diff options
author | Damjan Marion <damarion@cisco.com> | 2016-12-19 23:05:39 +0100 |
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committer | Damjan Marion <damarion@cisco.com> | 2016-12-28 12:25:14 +0100 |
commit | 7cd468a3d7dee7d6c92f69a0bb7061ae208ec727 (patch) | |
tree | 5de62f8dbd3a752f5a676ca600e43d2652d1ff1a /src/vppinfra/random_buffer.h | |
parent | 696f1adec0df3b8f161862566dd9c86174302658 (diff) |
Reorganize source tree to use single autotools instance
Change-Id: I7b51f88292e057c6443b12224486f2d0c9f8ae23
Signed-off-by: Damjan Marion <damarion@cisco.com>
Diffstat (limited to 'src/vppinfra/random_buffer.h')
-rw-r--r-- | src/vppinfra/random_buffer.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/vppinfra/random_buffer.h b/src/vppinfra/random_buffer.h new file mode 100644 index 00000000000..eb318548b0a --- /dev/null +++ b/src/vppinfra/random_buffer.h @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/* + Copyright (c) 2005 Eliot Dresselhaus + + Permission is hereby granted, free of charge, to any person obtaining + a copy of this software and associated documentation files (the + "Software"), to deal in the Software without restriction, including + without limitation the rights to use, copy, modify, merge, publish, + distribute, sublicense, and/or sell copies of the Software, and to + permit persons to whom the Software is furnished to do so, subject to + the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +*/ + +#ifndef included_clib_random_buffer_h +#define included_clib_random_buffer_h + +#include <vppinfra/clib.h> +#include <vppinfra/random_isaac.h> + +typedef struct +{ + /* Two parallel ISAAC contexts for speed. */ + isaac_t ctx[2]; + + /* Random buffer. */ + uword *buffer; + + /* Cache up to 1 word worth of bytes for random data + less than one word at a time. */ + uword n_cached_bytes; + + union + { + u8 cached_bytes[sizeof (uword)]; + uword cached_word; + }; +} +clib_random_buffer_t; + +always_inline void +clib_random_buffer_free (clib_random_buffer_t * b) +{ + vec_free (b->buffer); +} + +/* Fill random buffer. */ +void clib_random_buffer_fill (clib_random_buffer_t * b, uword n_words); + +/* Initialize random buffer. */ +void clib_random_buffer_init (clib_random_buffer_t * b, uword seed); + +/* Returns word aligned random data, possibly filling buffer. */ +always_inline void * +clib_random_buffer_get_data (clib_random_buffer_t * b, uword n_bytes) +{ + uword n_words, i, l; + + l = b->n_cached_bytes; + if (n_bytes <= l) + { + b->n_cached_bytes = l - n_bytes; + return &b->cached_bytes[l]; + } + + n_words = n_bytes / sizeof (uword); + if (n_bytes % sizeof (uword)) + n_words++; + + /* Enough random words left? */ + if (PREDICT_FALSE (n_words > vec_len (b->buffer))) + clib_random_buffer_fill (b, n_words); + + i = vec_len (b->buffer) - n_words; + _vec_len (b->buffer) = i; + + if (n_bytes < sizeof (uword)) + { + b->cached_word = b->buffer[i]; + b->n_cached_bytes = sizeof (uword) - n_bytes; + return b->cached_bytes; + } + else + return b->buffer + i; +} + +#endif /* included_clib_random_buffer_h */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |