X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=head.c;h=0c8ef3d5907b8f020b90a7780c964fe281c4e905;hb=8a9b2c6448e32f16e4b65dbd4927d9108c007acc;hp=f4ebe05c9a66b27025fd84530e7793d1c7519d81;hpb=7ab9c7ee52db8759d457819f5480378fa3aa97cc;p=oweals%2Fbusybox.git

diff --git a/head.c b/head.c
index f4ebe05c9..0c8ef3d59 100644
--- a/head.c
+++ b/head.c
@@ -3,7 +3,7 @@
  * Mini head implementation for busybox
  *
  *
- * Copyright (C) 1999,2000 by Lineo, inc.
+ * Copyright (C) 1999,2000,2001 by Lineo, inc.
  * Written by John Beppu <beppu@lineo.com>
  *
  * This program is free software; you can redistribute it and/or modify
@@ -22,32 +22,23 @@
  *
  */
 
-#include "internal.h"
 #include <errno.h>
 #include <stdio.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <string.h>
+#include "busybox.h"
 
-const char head_usage[] =
-	"head [OPTION] [FILE]...\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
-	"\nPrint first 10 lines of each FILE to standard output.\n"
-	"With more than one FILE, precede each with a header giving the\n"
-	"file name. With no FILE, or when FILE is -, read standard input.\n\n"
-
-	"Options:\n" "\t-n NUM\t\tPrint first NUM lines instead of first 10\n"
-#endif
-	;
-
-int head(int len, FILE * src)
+static int head(int len, FILE *fp)
 {
 	int i;
-	char buffer[1024];
+	char *input;
 
 	for (i = 0; i < len; i++) {
-		fgets(buffer, 1024, src);
-		if (feof(src)) {
+		if ((input = get_line_from_file(fp)) == NULL)
 			break;
-		}
-		fputs(buffer, stdout);
+		fputs(input, stdout);
+		free(input);
 	}
 	return 0;
 }
@@ -55,61 +46,54 @@ int head(int len, FILE * src)
 /* BusyBoxed head(1) */
 int head_main(int argc, char **argv)
 {
-	char opt;
-	int len = 10, tmplen, i;
+	FILE *fp;
+	int need_headers, opt, len = 10, status = EXIT_SUCCESS;
 
 	/* parse argv[] */
-	for (i = 1; i < argc; i++) {
-		if (argv[i][0] == '-') {
-			opt = argv[i][1];
-			switch (opt) {
-			case 'n':
-				tmplen = 0;
-				if (++i < argc)
-					tmplen = atoi(argv[i]);
-				if (tmplen < 1)
-					usage(head_usage);
-				len = tmplen;
+	while ((opt = getopt(argc, argv, "n:")) > 0) {
+		switch (opt) {
+		case 'n':
+			len = atoi(optarg);
+			if (len >= 1)
 				break;
-			case '-':
-			case 'h':
-				usage(head_usage);
-			default:
-				fprintf(stderr, "head: invalid option -- %c\n", opt);
-				usage(head_usage);
-			}
-		} else {
-			break;
+			/* fallthrough */
+		default:
+			show_usage();
 		}
 	}
 
 	/* get rest of argv[] or stdin if nothing's left */
-	if (i >= argc) {
+	if (argv[optind] == NULL) {
 		head(len, stdin);
+		return status;
+	} 
 
-	} else {
-		int need_headers = ((argc - i) > 1);
-
-		for (; i < argc; i++) {
-			FILE *src;
-
-			src = fopen(argv[i], "r");
-			if (!src) {
-				fprintf(stderr, "head: %s: %s\n", argv[i],
-						strerror(errno));
-			} else {
-				/* emulating GNU behaviour */
-				if (need_headers) {
-					fprintf(stdout, "==> %s <==\n", argv[i]);
-				}
-				head(len, src);
-				if (i < argc - 1) {
-					fprintf(stdout, "\n");
-				}
+	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]);
 			}
+			head(len, fp);
+			if (errno) {
+				perror_msg("%s", argv[optind]);
+				status = EXIT_FAILURE;
+				errno = 0;
+			}
+			if (optind < argc - 1)
+				putchar('\n');
+			if (fp != stdin)
+				fclose(fp);
 		}
+		optind++;
 	}
-	exit(0);
-}
 
-/* $Id: head.c,v 1.10 2000/05/12 19:41:47 erik Exp $ */
+	return status;
+}