[hackers] [sbase] Add f-flag to tail(1) and refactor code || FRIGN

From: <git_AT_suckless.org>
Date: Mon, 9 Feb 2015 16:25:08 +0100 (CET)

commit 8ae583f473250a71cc7c0fd2b68d149141d0c7fc
Author: FRIGN <dev_AT_frign.de>
Date: Mon Feb 9 15:06:17 2015 +0100

    Add f-flag to tail(1) and refactor code

diff --git a/tail.c b/tail.c
index a678a93..3ea4739 100644
--- a/tail.c
+++ b/tail.c
_AT_@ -8,26 +8,68 @@
 #include "text.h"
 #include "util.h"
 
-static void dropinit(FILE *, const char *, long);
-static void taketail(FILE *, const char *, long);
+static int fflag = 0;
+
+static void
+dropinit(FILE *fp, const char *str, long n)
+{
+ char *buf = NULL;
+ size_t size = 0;
+ ssize_t len;
+ unsigned long i = 0;
+
+ while (i < n && (len = getline(&buf, &size, fp)) != -1)
+ if (len > 0 && buf[len - 1] == '\n')
+ i++;
+ free(buf);
+ concat(fp, str, stdout, "<stdout>");
+}
+
+static void
+taketail(FILE *fp, const char *str, long n)
+{
+ char **ring = NULL;
+ long i, j;
+ size_t *size = NULL;
+
+ ring = ecalloc(n, sizeof *ring);
+ size = ecalloc(n, sizeof *size);
+
+ for (i = j = 0; getline(&ring[i], &size[i], fp) != -1; i = j = (i + 1) % n)
+ ;
+ if (ferror(fp))
+ eprintf("%s: read error:", str);
+
+ do {
+ if (ring[j]) {
+ fputs(ring[j], stdout);
+ free(ring[j]);
+ }
+ } while ((j = (j + 1) % n) != i);
+
+ free(ring);
+ free(size);
+}
 
 static void
 usage(void)
 {
- eprintf("usage: %s [-n lines] [file]\n", argv0);
+ eprintf("usage: %s [-f] [-n lines] [file ...]\n", argv0);
 }
 
 int
 main(int argc, char *argv[])
 {
- long n = 10;
         FILE *fp;
+ size_t n = 10, tmpsize;
+ int ret = 0, newline, many;
+ char *lines, *tmp;
         void (*tail)(FILE *, const char *, long) = taketail;
- char *lines;
- int ret = 0;
- int newline, many;
 
         ARGBEGIN {
+ case 'f':
+ fflag = 1;
+ break;
         case 'n':
                 lines = EARGF(usage());
                 n = estrtonum(lines, 0, LONG_MAX);
_AT_@ -40,10 +82,12 @@ main(int argc, char *argv[])
         default:
                 usage();
         } ARGEND;
- if (argc == 0) {
+
+ if (argc == 0)
                 tail(stdin, "<stdin>", n);
- } else {
- many = argc > 1;
+ else {
+ if ((many = argc > 1) && fflag)
+ usage();
                 for (newline = 0; argc > 0; argc--, argv++) {
                         if (!(fp = fopen(argv[0], "r"))) {
                                 weprintf("fopen %s:", argv[0]);
_AT_@ -55,48 +99,23 @@ main(int argc, char *argv[])
                                        newline ? "\n" : "", argv[0]);
                         newline = 1;
                         tail(fp, argv[0], n);
+
+ if (fflag && argc == 1) {
+ for(;; tmp = NULL, tmpsize = 0) {
+ while (getline(&tmp, &tmpsize, fp) != -1) {
+ fputs(tmp, stdout);
+ fflush(stdout);
+ free(tmp);
+ tmp = NULL;
+ tmpsize = 0;
+ }
+ if (ferror(fp))
+ eprintf("readline '%s':", argv[0]);
+ clearerr(fp);
+ }
+ }
                         fclose(fp);
                 }
         }
         return ret;
 }
-
-static void
-dropinit(FILE *fp, const char *str, long n)
-{
- char *buf = NULL;
- size_t size = 0;
- ssize_t len;
- unsigned long i = 0;
-
- while (i < n && ((len = getline(&buf, &size, fp)) != -1))
- if (len && buf[len - 1] == '\n')
- i++;
- free(buf);
- concat(fp, str, stdout, "<stdout>");
-}
-
-static void
-taketail(FILE *fp, const char *str, long n)
-{
- char **ring = NULL;
- long i, j;
- size_t *size = NULL;
-
- ring = ecalloc(n, sizeof *ring);
- size = ecalloc(n, sizeof *size);
-
- for (i = j = 0; getline(&ring[i], &size[i], fp) != -1; i = j = (i + 1) % n)
- ;
- if (ferror(fp))
- eprintf("%s: read error:", str);
-
- do {
- if (ring[j]) {
- fputs(ring[j], stdout);
- free(ring[j]);
- }
- } while ((j = (j+1)%n) != i);
- free(ring);
- free(size);
-}
Received on Mon Feb 09 2015 - 16:25:08 CET