35 lines
713 B
C
35 lines
713 B
C
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/*
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* Given a filename, outputs a 32bit key for use in
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* context keyed payload encoding. The key is derived from
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* XOR-ing the st_size and st_mtime fields of the
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* relevant struct stat for this file.
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*
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* Author: Dimitris Glynos <dimitris at census-labs.com>
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*/
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#include <stdio.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <unistd.h>
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int main(int argc, char *argv[])
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{
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char *filename;
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struct stat stat_buf;
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if (argc != 2) {
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fprintf(stderr, "usage: %s <filename>\n", argv[0]);
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return 1;
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}
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filename = argv[1];
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if (stat(filename, &stat_buf) == -1) {
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perror("error while stat(2)-ing file");
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return 1;
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}
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printf("%#.8lx\n", stat_buf.st_mtime ^ stat_buf.st_size);
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return 0;
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}
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