Rewrote head to perservere when it can't open a file, and share code

with cat.

1 files changed, 43 insertions, 50 deletions

diff --git a/coreutils/head.c b/coreutils/head.c
index c232e1153..92b43bae2 100644
--- a/coreutils/head.c
+++ b/coreutils/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;
+}