summaryrefslogtreecommitdiff
path: root/head.c
diff options
context:
space:
mode:
authorMatt Kraai2000-09-27 04:09:22 +0000
committerMatt Kraai2000-09-27 04:09:22 +0000
commitc0321f9bc67e0a90dbd12f4d7b39d6991c9899cd (patch)
tree119d96c575fe50db7026ee96d476006823dd0f4b /head.c
parente7c1af1e0dc1440483d7f195f15eb0df5cf70a04 (diff)
downloadbusybox-c0321f9bc67e0a90dbd12f4d7b39d6991c9899cd.zip
busybox-c0321f9bc67e0a90dbd12f4d7b39d6991c9899cd.tar.gz
Rewrote head to perservere when it can't open a file, and share code
with cat.
Diffstat (limited to 'head.c')
-rw-r--r--head.c93
1 files changed, 43 insertions, 50 deletions
diff --git a/head.c b/head.c
index c232e11..92b43ba 100644
--- a/head.c
+++ b/head.c
@@ -26,17 +26,16 @@
#include <errno.h>
#include <stdio.h>
-int head(int len, FILE * src)
+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;
}
@@ -44,60 +43,54 @@ 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:
- errorMsg("invalid option -- %c\n", opt);
- usage(head_usage);
- }
- } else {
- break;
+ /* fallthrough */
+ default:
+ usage(head_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) {
- errorMsg("%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) {
+ fprintf(stdout, "==> %s <==\n", argv[optind]);
+ }
+ head(len, fp);
+ if (errno) {
+ errorMsg("%s: %s\n", argv[optind], strerror(errno));
+ status = EXIT_FAILURE;
+ errno = 0;
}
+ if (optind < argc - 1)
+ fprintf(stdout, "\n");
+ if (fp != stdin)
+ fclose(fp);
}
+ optind++;
}
- return(0);
-}
-/* $Id: head.c,v 1.14 2000/09/25 21:45:57 andersen Exp $ */
+ return status;
+}