57 lines
969 B
C
57 lines
969 B
C
#include <common.h>
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#include <command.h>
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#include <linux/stat.h>
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#include <malloc.h>
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#include <fs.h>
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#define MAGIC 0x19691228
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static int do_alternate(int argc, char *argv[])
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{
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void *buf;
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size_t size;
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ulong *ptr, val = 0, bitcount = 0;
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if (argc != 2)
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return COMMAND_ERROR_USAGE;
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buf = read_file(argv[1], &size);
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if (!buf)
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return 1;
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ptr = buf;
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if ((*ptr) != MAGIC) {
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printf("Wrong magic! Expected 0x%08x, got 0x%08lx.\n", MAGIC, *ptr);
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return 1;
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}
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ptr++;
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while ((ulong)ptr <= (ulong)buf + size && !(val = *ptr++))
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bitcount += 32;
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if (val) {
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do {
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if (val & 1)
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break;
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bitcount++;
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} while (val >>= 1);
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}
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printf("Bitcount : %ld\n", bitcount);
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free(buf);
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return (bitcount & 1) ? 3 : 2;
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}
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static const __maybe_unused char cmd_alternate_help[] =
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"Usage: alternate <file>"
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"\n";
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BAREBOX_CMD_START(alternate)
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.cmd = do_alternate,
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.usage = "count zero bits in a file",
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BAREBOX_CMD_HELP(cmd_alternate_help)
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BAREBOX_CMD_END
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