40 lines
838 B
C
40 lines
838 B
C
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#if HAVE_CONFIG_H
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#include <config.h>
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#endif /* HAVE_CONFIG_H */
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#include <stdio.h>
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#include <stdlib.h> /* For free(3). */
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#include "system.h"
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int
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main(void)
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{
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FILE *fp;
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char *buf;
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unsigned int random;
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if ((fp = fopen("/dev/urandom", "r")) == NULL &&
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(fp = fopen("/dev/random", "r")) == NULL) {
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perror("Cannot open random device");
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return 1;
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}
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if (fread(&random, sizeof(random), 1, fp) != 1) {
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(void)fputs("Cannot read random device.", stderr);
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return 1;
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}
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if (fclose(fp) != 0) {
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perror("Cannot close random device");
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return 1;
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}
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/* We never heard of printf(3), so we use asprintf(3)/puts(3) :-) */
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if (asprintf(&buf, "Random %zu-bit integer: %#.*x",
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sizeof(random) * 8, (int)sizeof(random) * 2, random) < 0) {
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perror("asprintf(3) failed");
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return 1;
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}
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(void)puts(buf);
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free(buf);
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return 0;
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}
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