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34 lines
504 B
C
34 lines
504 B
C
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#define _DEFAULT_SOURCE
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#include <unistd.h>
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#include <sys/random.h>
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#include <pthread.h>
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#include <errno.h>
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int getentropy(void *buffer, size_t len)
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{
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int cs, ret = 0;
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char *pos = buffer;
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if (len > 256) {
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errno = EIO;
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return -1;
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}
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pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
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while (len) {
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ret = getrandom(pos, len, 0);
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if (ret < 0) {
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if (errno == EINTR) continue;
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else break;
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}
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pos += ret;
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len -= ret;
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ret = 0;
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}
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pthread_setcancelstate(cs, 0);
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return ret;
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}
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