This patch from Adam Heath <doogie@debian.org>, makes print_file

(used by cat, grep, sed, etc) quite a bit faster.


git-svn-id: svn://busybox.net/trunk/busybox@2648 69ca8d6d-28ef-0310-b511-8ec308f3f277

3 files changed, 70 insertions, 5 deletions

diff --git a/libbb/copyfd.c b/libbb/copyfd.c
new file mode 100644
index 000000000..253a8cf6e
--- /dev/null
+++ b/libbb/copyfd.c
@@ -0,0 +1,67 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2001 Erik Andersen <andersee@debian.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include "libbb.h"
+
+
+extern size_t copyfd(int fd1, int fd2)
+{
+        char buf[32768], *writebuf;
+        int status = TRUE;
+        size_t totalread = 0, bytesread, byteswritten;
+
+        while(status) {
+                bytesread = read(fd1, &buf, sizeof(buf));
+                if(bytesread == -1) {
+                        error_msg("read: %s", strerror(errno));
+                        status = FALSE;
+                        break;
+                }
+                byteswritten = 0;
+                writebuf = buf;
+                while(bytesread) {
+                        byteswritten = write( fd2, &writebuf, bytesread );
+                        if(byteswritten == -1) {
+                                error_msg("write: %s", strerror(errno));
+                                status = FALSE;
+                                break;
+                        }
+                        bytesread -= byteswritten;
+                        writebuf += byteswritten;
+                }
+        }
+        if ( status == TRUE )
+                return totalread;
+        else
+                return -1;
+}
+
+/* END CODE */
+/*
+Local Variables:
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/
diff --git a/libbb/libbb.h b/libbb/libbb.h
index f34bee8f7..7ab06388a 100644
--- a/libbb/libbb.h
+++ b/libbb/libbb.h
@@ -128,6 +128,7 @@ extern pid_t* find_pid_by_name( char* pidName);
 extern char *find_real_root_device_name(const char* name);
 extern char *get_line_from_file(FILE *file);
 extern void print_file(FILE *file);
+extern size_t copyfd(int fd1, int fd2);
 extern int print_file_by_name(char *filename);
 extern char process_escape_sequence(const char **ptr);
 extern char *get_last_path_component(char *path);
diff --git a/libbb/print_file.c b/libbb/print_file.c
index b47723454..bfedc5eff 100644
--- a/libbb/print_file.c
+++ b/libbb/print_file.c
@@ -26,12 +26,9 @@
 
 extern void print_file(FILE *file)
 {
-        int c;
-
-        while ((c = getc(file)) != EOF)
-                putc(c, stdout);
-        fclose(file);
         fflush(stdout);
+        copyfd(fileno(file), fileno(stdout));
+        fclose(file);
 }
 
 extern int print_file_by_name(char *filename)