| /* See LICENSE file for copyright and license details. */ |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "util.h" |
| |
| static void |
| head(FILE *fp, const char *fname, size_t n) |
| { |
| char *buf = NULL; |
| size_t i = 0, size = 0; |
| ssize_t len; |
| |
| while (i < n && (len = getline(&buf, &size, fp)) > 0) { |
| fputs(buf, stdout); |
| i += (buf[len - 1] == '\n'); |
| } |
| free(buf); |
| if (ferror(fp)) |
| eprintf("getline %s:", fname); |
| } |
| |
| static void |
| usage(void) |
| { |
| eprintf("usage: %s [-num | -n num] [file ...]\n", argv0); |
| } |
| |
| int |
| main(int argc, char *argv[]) |
| { |
| size_t n = 10; |
| FILE *fp; |
| int ret = 0, newline = 0, many = 0; |
| |
| ARGBEGIN { |
| case 'n': |
| n = estrtonum(EARGF(usage()), 0, MIN(LLONG_MAX, SIZE_MAX)); |
| break; |
| ARGNUM: |
| n = ARGNUMF(); |
| break; |
| default: |
| usage(); |
| } ARGEND |
| |
| if (!argc) { |
| head(stdin, "<stdin>", n); |
| } else { |
| many = argc > 1; |
| for (newline = 0; *argv; argc--, argv++) { |
| if (!strcmp(*argv, "-")) { |
| *argv = "<stdin>"; |
| fp = stdin; |
| } else if (!(fp = fopen(*argv, "r"))) { |
| weprintf("fopen %s:", *argv); |
| ret = 1; |
| continue; |
| } |
| if (many) { |
| if (newline) |
| putchar('\n'); |
| printf("==> %s <==\n", *argv); |
| } |
| newline = 1; |
| head(fp, *argv, n); |
| if (fp != stdin && fshut(fp, *argv)) |
| ret = 1; |
| } |
| } |
| |
| ret |= fshut(stdin, "<stdin>") | fshut(stdout, "<stdout>"); |
| |
| return ret; |
| } |