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43 lines
691 B
C
43 lines
691 B
C
#include <ent/ent.h>
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#if defined(ENT_URANDOM)
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#warning "libent: using /dev/urandom..."
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#include <assert.h>
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#include <errno.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <sys/types.h>
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int
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ent_getentropy(void* buf, size_t len)
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{
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int fd;
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ssize_t ret;
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char* cuf = buf;
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assert(len <= 256);
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if (-1 == (fd = open("/dev/urandom", O_RDONLY))) {
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return -1;
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}
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while (len != 0 && (ret = read(fd, cuf, len)) != 0) {
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if (ret == -1) {
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if (errno == EINTR)
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continue;
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break;
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}
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len -= ret;
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cuf += ret;
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}
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(void) close(fd);
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if (ret == 0) {
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ret = -1;
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errno = EIO;
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}
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return ret < 0 ? ret : 0;
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}
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#endif /* ENT_USE_URANDOM */
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