[src/trunk]: src/usr.bin/head Remove 2**31 limit on the number of lines or by...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/30cc9030789e
branches:  trunk
changeset: 753539:30cc9030789e
user:      joerg <joerg%NetBSD.org@localhost>
date:      Wed Mar 31 21:52:11 2010 +0000

description:
Remove 2**31 limit on the number of lines or bytes to process.
For the byte operations, process in blocks of 64KB.

diffstat:

 usr.bin/head/head.c |  57 ++++++++++++++++++++++++++++++++++------------------
 1 files changed, 37 insertions(+), 20 deletions(-)

diffs (120 lines):

diff -r 429d97d2db99 -r 30cc9030789e usr.bin/head/head.c
--- a/usr.bin/head/head.c       Wed Mar 31 21:01:03 2010 +0000
+++ b/usr.bin/head/head.c       Wed Mar 31 21:52:11 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: head.c,v 1.21 2010/03/31 15:01:51 joerg Exp $  */
+/*     $NetBSD: head.c,v 1.22 2010/03/31 21:52:11 joerg Exp $  */
 
 /*
  * Copyright (c) 1980, 1987, 1992, 1993
@@ -39,7 +39,7 @@
 #if 0
 static char sccsid[] = "@(#)head.c     8.2 (Berkeley) 5/4/95";
 #else
-__RCSID("$NetBSD: head.c,v 1.21 2010/03/31 15:01:51 joerg Exp $");
+__RCSID("$NetBSD: head.c,v 1.22 2010/03/31 21:52:11 joerg Exp $");
 #endif
 #endif /* not lint */
 
@@ -48,6 +48,7 @@
 #include <ctype.h>
 #include <err.h>
 #include <errno.h>
+#include <inttypes.h>
 #include <limits.h>
 #include <locale.h>
 #include <stdio.h>
@@ -61,7 +62,7 @@
  * Bill Joy UCB August 24, 1977
  */
 
-static void head(FILE *, long, long);
+static void head(FILE *, intmax_t, intmax_t);
 static void obsolete(char *[]);
 __dead static void usage(void);
 
@@ -72,8 +73,8 @@
        int ch;
        FILE *fp;
        int first;
-       long linecnt;
-       long bytecnt;
+       uintmax_t linecnt;
+       uintmax_t bytecnt;
        char *ep;
        int eval = 0;
        int qflag = 0;
@@ -87,22 +88,18 @@
                switch(ch) {
                case 'c':
                        errno = 0;
-                       bytecnt = strtol(optarg, &ep, 10);
-                       if ((bytecnt == LONG_MIN || bytecnt == LONG_MAX) &&
-                           errno == ERANGE)
+                       bytecnt = strtoimax(optarg, &ep, 10);
+                       if ((bytecnt == INTMAX_MAX && errno == ERANGE) ||
+                           *ep || bytecnt <= 0)
                                err(1, "illegal byte count -- %s", optarg);
-                       else if (*ep || bytecnt <= 0)
-                               errx(1, "illegal byte count -- %s", optarg);
                        break;
 
                case 'n':
                        errno = 0;
-                       linecnt = strtol(optarg, &ep, 10);
-                       if ((linecnt == LONG_MIN || linecnt == LONG_MAX) &&
-                           errno == ERANGE)
+                       linecnt = strtoimax(optarg, &ep, 10);
+                       if ((linecnt == INTMAX_MAX && errno == ERANGE) ||
+                           *ep || linecnt <= 0)
                                err(1, "illegal line count -- %s", optarg);
-                       else if (*ep || linecnt <= 0)
-                               errx(1, "illegal line count -- %s", optarg);
                        break;
 
                case 'q':
@@ -143,19 +140,39 @@
 }
 
 static void
-head(FILE *fp, long cnt, long bytecnt)
+head(FILE *fp, intmax_t cnt, intmax_t bytecnt)
 {
+       char buf[65536];
+       size_t len, rv, rv2;
        int ch;
 
-       if (bytecnt)
-               cnt = bytecnt;
-       while (cnt--)
+       if (bytecnt) {
+               while (bytecnt) {
+                       len = sizeof(buf);
+                       if (bytecnt > (intmax_t)sizeof(buf))
+                               len = sizeof(buf);
+                       else
+                               len = bytecnt;
+                       rv = fread(buf, 1, len, fp);
+                       if (rv == 0)
+                               break; /* Distinguish EOF and error? */
+                       rv2 = fwrite(buf, 1, rv, stdout);
+                       if (rv2 != rv) {
+                               if (feof(stdout))
+                                       errx(1, "EOF on stdout");
+                               else
+                                       err(1, "failure writing to stdout");
+                       }
+                       bytecnt -= rv;
+               }
+       } else {
                while ((ch = getc(fp)) != EOF) {
                        if (putchar(ch) == EOF)
                                err(1, "stdout");
-                       if (ch == '\n' || bytecnt)
+                       if (ch == '\n' && --cnt == 0)
                                break;
                }
+       }
 }
 
 static void