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authorGravatar Manuel Novoa III <mjn3@codepoet.org>2003-03-19 09:13:01 +0000
committerGravatar Manuel Novoa III <mjn3@codepoet.org>2003-03-19 09:13:01 +0000
commitcad5364599eb5062d59e0c397ed638ddd61a8d5d (patch)
treea318d0f03aa076c74b576ea45dc543a5669e8e91 /coreutils/head.c
parente01f9662a5bd5d91be4f6b3941b57fff73cd5af1 (diff)
downloadbusybox-cad5364599eb5062d59e0c397ed638ddd61a8d5d.tar.gz
busybox-cad5364599eb5062d59e0c397ed638ddd61a8d5d.tar.bz2
Major coreutils update.
Diffstat (limited to 'coreutils/head.c')
-rw-r--r--coreutils/head.c154
1 files changed, 95 insertions, 59 deletions
diff --git a/coreutils/head.c b/coreutils/head.c
index ad21e1b95..dab4de11b 100644
--- a/coreutils/head.c
+++ b/coreutils/head.c
@@ -1,9 +1,8 @@
/* vi: set sw=4 ts=4: */
/*
- * Mini head implementation for busybox
+ * head implementation for busybox
*
- * Copyright (C) 1999 by Lineo, inc. and John Beppu
- * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
+ * Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -21,82 +20,119 @@
*
*/
+/* BB_AUDIT SUSv3 compliant */
+/* BB_AUDIT GNU compatible -c, -q, and -v options in 'fancy' configuration. */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/head.html */
+
#include <stdio.h>
-#include <getopt.h>
#include <stdlib.h>
-#include <string.h>
+#include <limits.h>
#include <ctype.h>
+#include <unistd.h>
#include "busybox.h"
-static int head(int len, FILE *fp)
-{
- int i;
- char *input;
+static const char head_opts[] =
+ "n:"
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+ "c:qv"
+#endif
+ ;
- for (i = 0; i < len; i++) {
- if ((input = get_line_from_file(fp)) == NULL)
- break;
- fputs(input, stdout);
- free(input);
- }
- return 0;
-}
+static const char header_fmt_str[] = "\n==> %s <==\n";
-/* BusyBoxed head(1) */
int head_main(int argc, char **argv)
{
+ unsigned long count = 10;
+ unsigned long i;
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+ int count_bytes = 0;
+ int header_threshhold = 1;
+#endif
+
FILE *fp;
- int need_headers, opt, len = 10, status = EXIT_SUCCESS;
+ const char *fmt;
+ char *p;
+ int opt;
+ int c;
+ int retval = EXIT_SUCCESS;
- if (( argc >= 2 ) && ( argv [1][0] == '-' ) && isdigit ( argv [1][1] )) {
- len = atoi ( &argv [1][1] );
- optind = 2;
+ /* Allow legacy syntax of an initial numeric option without -n. */
+ if ((argc > 1) && (argv[1][0] == '-')
+ /* && (isdigit)(argv[1][1]) */
+ && (((unsigned int)(argv[1][1] - '0')) <= 9)
+ ) {
+ --argc;
+ ++argv;
+ p = (*argv) + 1;
+ goto GET_COUNT;
}
- /* parse argv[] */
- while ((opt = getopt(argc, argv, "n:")) > 0) {
- switch (opt) {
- case 'n':
- len = atoi(optarg);
- if (len >= 0)
+ while ((opt = getopt(argc, argv, head_opts)) > 0) {
+ switch(opt) {
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+ case 'q':
+ header_threshhold = INT_MAX;
+ break;
+ case 'v':
+ header_threshhold = -1;
break;
- /* fallthrough */
- default:
- show_usage();
+ case 'c':
+ count_bytes = 1;
+ /* fall through */
+#endif
+ case 'n':
+ p = optarg;
+ GET_COUNT:
+ count = bb_xgetularg10(p);
+ break;
+ default:
+ bb_show_usage();
}
}
- /* get rest of argv[] or stdin if nothing's left */
- if (argv[optind] == NULL) {
- head(len, stdin);
- return status;
- }
+ argv += optind;
+ if (!*argv) {
+ *--argv = "-";
+ }
- need_headers = optind != (argc - 1);
- while (argv[optind]) {
- if (strcmp(argv[optind], "-") == 0) {
- fp = stdin;
- argv[optind] = "standard input";
- } else {
- if ((fp = wfopen(argv[optind], "r")) == NULL)
- status = EXIT_FAILURE;
- }
- if (fp) {
- if (need_headers) {
- printf("==> %s <==\n", argv[optind]);
+ fmt = header_fmt_str + 1;
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+ if (argc - optind <= header_threshhold) {
+ header_threshhold = 0;
+ }
+#else
+ if (argc <= optind + 1) {
+ fmt += 11;
+ }
+ /* Now define some things here to avoid #ifdefs in the code below.
+ * These should optimize out of the if conditions below. */
+#define header_threshhold 1
+#define count_bytes 0
+#endif
+
+ do {
+ if ((fp = bb_wfopen_input(*argv)) != NULL) {
+ if (fp == stdin) {
+ *argv = (char *) bb_msg_standard_input;
}
- head(len, fp);
- if (ferror(fp)) {
- perror_msg("%s", argv[optind]);
- status = EXIT_FAILURE;
+ if (header_threshhold) {
+ bb_printf(fmt, *argv);
}
- if (optind < argc - 1)
- putchar('\n');
- if (fp != stdin)
- fclose(fp);
+ i = count;
+ while (i && ((c = getc(fp)) != EOF)) {
+ if (count_bytes || (c == '\n')) {
+ --i;
+ }
+ putchar(c);
+ }
+ if (bb_fclose_nonstdin(fp)) {
+ bb_perror_msg("%s", *argv); /* Avoid multibyte problems. */
+ retval = EXIT_FAILURE;
+ }
+ bb_xferror_stdout();
}
- optind++;
- }
+ fmt = header_fmt_str;
+ } while (*++argv);
- return status;
+ bb_fflush_stdout_and_exit(retval);
}