5bc8c005a8
Signed-off-by: Pere Orga <gotrunks@gmail.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
48 lines
1.0 KiB
C
48 lines
1.0 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* readahead implementation for busybox
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*
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* Preloads the given files in RAM, to reduce access time.
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* Does this by calling the readahead(2) system call.
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*
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* Copyright (C) 2006 Michael Opdenacker <michael@free-electrons.com>
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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//usage:#define readahead_trivial_usage
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//usage: "[FILE]..."
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//usage:#define readahead_full_usage "\n\n"
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//usage: "Preload FILEs to RAM"
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#include "libbb.h"
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int readahead_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int readahead_main(int argc UNUSED_PARAM, char **argv)
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{
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int retval = EXIT_SUCCESS;
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if (!argv[1]) {
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bb_show_usage();
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}
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while (*++argv) {
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int fd = open_or_warn(*argv, O_RDONLY);
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if (fd >= 0) {
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off_t len;
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int r;
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/* fdlength was reported to be unreliable - use seek */
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len = xlseek(fd, 0, SEEK_END);
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xlseek(fd, 0, SEEK_SET);
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r = readahead(fd, 0, len);
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close(fd);
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if (r >= 0)
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continue;
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}
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retval = EXIT_FAILURE;
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}
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return retval;
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}
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