58 lines
998 B
C
58 lines
998 B
C
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// SPDX-License-Identifier: GPL-2.0
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#define _GNU_SOURCE
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#include <errno.h>
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#include <fcntl.h>
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#include <limits.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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int main(int argc, char *argv[])
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{
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int fd;
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size_t size;
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ssize_t spliced;
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if (argc < 2) {
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fprintf(stderr, "Usage: %s INPUT [BYTES]\n", argv[0]);
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return EXIT_FAILURE;
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}
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fd = open(argv[1], O_RDONLY);
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if (fd < 0) {
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perror(argv[1]);
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return EXIT_FAILURE;
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}
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if (argc == 3)
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size = atol(argv[2]);
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else {
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struct stat statbuf;
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if (fstat(fd, &statbuf) < 0) {
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perror(argv[1]);
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return EXIT_FAILURE;
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}
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if (statbuf.st_size > INT_MAX) {
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fprintf(stderr, "%s: Too big\n", argv[1]);
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return EXIT_FAILURE;
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}
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size = statbuf.st_size;
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}
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/* splice(2) file to stdout. */
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spliced = splice(fd, NULL, STDOUT_FILENO, NULL,
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size, SPLICE_F_MOVE);
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if (spliced < 0) {
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perror("splice");
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return EXIT_FAILURE;
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}
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close(fd);
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return EXIT_SUCCESS;
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}
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