2004-04-21 03:06:03 +00:00
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#include <u.h>
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#include <libc.h>
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ulong
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truerand(void)
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{
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int i, n;
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uchar buf[sizeof(ulong)];
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static int randfd = -1;
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if(randfd < 0){
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randfd = open("/dev/random", OREAD);
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2005-08-11 03:20:57 +00:00
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if(randfd < 0)
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randfd = open("/dev/srandom", OREAD); /* OpenBSD */
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if(randfd < 0)
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sysfatal("can't open /dev/random: %r");
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2004-04-21 03:06:03 +00:00
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fcntl(randfd, F_SETFD, FD_CLOEXEC);
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}
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for(i=0; i<sizeof(buf); i += n)
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if((n = readn(randfd, buf+i, sizeof(buf)-i)) < 0)
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sysfatal("can't read /dev/random: %r");
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return *((ulong*)buf);
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}
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