X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=head.c;h=0c8ef3d5907b8f020b90a7780c964fe281c4e905;hb=8a9b2c6448e32f16e4b65dbd4927d9108c007acc;hp=a9d024e6216858c4282276c013d57d36bba5c270;hpb=25ab6534576eb0dbb636867ff992ab3a69ae06bc;p=oweals%2Fbusybox.git

diff --git a/head.c b/head.c
index a9d024e62..0c8ef3d59 100644
--- a/head.c
+++ b/head.c
@@ -1,8 +1,9 @@
+/* vi: set sw=4 ts=4: */
 /*
  * Mini head implementation for busybox
  *
  *
- * Copyright (C) 1999 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
@@ -21,87 +22,78 @@
  *
  */
 
-#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[] =
-"Usage: head [FILE]...\n\n"
-"Print 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";
-
-int
-head(int len, FILE *src)
+static int head(int len, FILE *fp)
 {
-    int	    i;
-    char    buffer[1024];
+	int i;
+	char *input;
 
-    for (i = 0; i < len; i++) {
-	fgets(buffer, 1024, src);
-	if (feof(src)) { break; }
-	fputs(buffer, stdout);
-    }
-    return 0;
+	for (i = 0; i < len; i++) {
+		if ((input = get_line_from_file(fp)) == NULL)
+			break;
+		fputs(input, stdout);
+		free(input);
+	}
+	return 0;
 }
 
 /* BusyBoxed head(1) */
-int
-head_main(int argc, char **argv)
+int head_main(int argc, char **argv)
 {
-    int	    i = 1;
-    char    opt;
-    int	    len = 10;
-
-    /* 1st option is potentially special */
-    if ((argc > 1) && (argv[1][0] == '-') && isDecimal(argv[1][1])) {
-	int tmplen = atoi(&argv[1][1]);
-	if (tmplen) { len = tmplen; }
-	i = 2;
-    }
+	FILE *fp;
+	int need_headers, opt, len = 10, status = EXIT_SUCCESS;
 
-    /* parse argv[] */
-    for ( ; i < argc; i++) {
-	if (argv[i][0] == '-') {
-	    opt = argv[i][1];
-	    switch (opt) {
-		case '-':
-		    break;
-		case 'h':
-		    usage(head_usage);
+	/* parse argv[] */
+	while ((opt = getopt(argc, argv, "n:")) > 0) {
+		switch (opt) {
+		case 'n':
+			len = atoi(optarg);
+			if (len >= 1)
+				break;
+			/* fallthrough */
 		default:
-		    fprintf(stderr, "head: invalid option -- %c\n", opt);
-		    usage(head_usage);
-	    }
-	} else {
-	    break;
+			show_usage();
+		}
 	}
-    }
 
-    /* get rest of argv[] or stdin if nothing's left */
-    if (i >= argc) {
-	head(len, stdin);
+	/* get rest of argv[] or stdin if nothing's left */
+	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]);
+	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;
 		}
-		head(len, src);
-		if (i < argc - 1) {
-		    fprintf(stdout, "\n");
+		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 1.3 1999/12/15 19:29:09 beppu Exp $ */
+	return status;
+}