47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/* go-rec-nb-big.c -- nonblocking receive of something big on a channel.
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Copyright 2009 The Go Authors. All rights reserved.
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Use of this source code is governed by a BSD-style
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license that can be found in the LICENSE file. */
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#include <stdint.h>
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#include "channel.h"
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/* Return true if a value was received, false if not. */
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_Bool
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__go_receive_nonblocking_big (struct __go_channel* channel, void *val,
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_Bool *closed)
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{
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uintptr_t element_size;
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size_t alloc_size;
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size_t offset;
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if (channel == NULL)
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{
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if (closed != NULL)
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*closed = 0;
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return 0;
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}
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element_size = channel->element_type->__size;
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alloc_size = (element_size + sizeof (uint64_t) - 1) / sizeof (uint64_t);
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int data = __go_receive_nonblocking_acquire (channel);
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if (data != RECEIVE_NONBLOCKING_ACQUIRE_DATA)
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{
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__builtin_memset (val, 0, element_size);
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if (closed != NULL)
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*closed = data == RECEIVE_NONBLOCKING_ACQUIRE_CLOSED;
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return 0;
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}
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offset = channel->next_fetch * alloc_size;
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__builtin_memcpy (val, &channel->data[offset], element_size);
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__go_receive_release (channel);
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return 1;
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}
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