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/* cycletee - read from standard input and write to standard output, and write to files circularly.
Copyright (C) 1985, 1990-2006, 2008-2011 Free Software Foundation, Inc.
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 3 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, see <http://www.gnu.org/licenses/>. */
/* Mike Parker, Richard M. Stallman, and David MacKenzie
* Modified to cycletee by Liang Zhaohao */
#include <config.h>
#include <sys/types.h>
#include <signal.h>
#include <getopt.h>
#include "system.h"
#include "error.h"
#include "fadvise.h"
#include "stdio--.h"
#include "xfreopen.h"
#define min(a,b) \
({ __typeof__ (a) _a = (a); \
__typeof__ (b) _b = (b); \
_a < _b ? _a : _b; })
#define eprintf(...) \
fprintf(stderr, "Error: "); \
fprintf(stderr, __VA_ARGS__); \
fprintf(stderr, "\n");
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "cycletee"
#define AUTHORS \
proper_name ("Mike Parker"), \
proper_name ("Richard M. Stallman"), \
proper_name ("David MacKenzie"), \
proper_name ("Liang Zhaohao (liangvls@gmail.com)")
static bool tee_files (int nfiles, const char **files);
/* If true, append to output files rather than truncating them. */
static bool append;
/* If true, ignore interrupts. */
static bool ignore_interrupts;
static bool no_stdout;
static struct option const long_options[] =
{
{"append", no_argument, NULL, 'a'},
{"ignore-interrupts", no_argument, NULL, 'i'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0}
};
void
usage (int status)
{
if (status != EXIT_SUCCESS)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
fputs (_("\
Copy standard input to each FILE, and also to standard output.\n\
\n\
-a, --append append to the given FILEs, do not overwrite\n\
-i, --ignore-interrupts ignore interrupt signals\n\
-n, no output to stdout\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
fputs (_("\
\n\
If a FILE is -, copy again to standard output.\n\
"), stdout);
emit_ancillary_info ();
}
exit (status);
}
int
main (int argc, char **argv)
{
bool ok;
int optc;
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
atexit (close_stdout);
append = false;
ignore_interrupts = false;
no_stdout = false;
while ((optc = getopt_long (argc, argv, "ain", long_options, NULL)) != -1)
{
switch (optc)
{
case 'a':
append = true;
break;
case 'i':
ignore_interrupts = true;
break;
case 'n':
no_stdout = true;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (EXIT_FAILURE);
}
}
if (ignore_interrupts)
signal (SIGINT, SIG_IGN);
/* Do *not* warn if tee is given no file arguments.
POSIX requires that it work when given no arguments. */
ok = tee_files (argc - optind, (const char **) &argv[optind]);
if (close (STDIN_FILENO) != 0)
error (EXIT_FAILURE, errno, _("standard input"));
exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
}
/* Copy the standard input into each of the NFILES files in FILES
and into the standard output.
Return true if successful. */
static bool
tee_files (int nfiles, const char **files)
{
FILE **descriptors;
char buffer[BUFSIZ];
size_t bytes_read;
int i;
bool ok = true;
char const *mode_string =
(O_BINARY
? (append ? "ab" : "wb")
: (append ? "a" : "w"));
bool flag_break = false;
bool flag_continue = false;
int backup_i;
char* ptr;
char* next_ptr;
size_t len;
size_t remain;
bool has_entire_line = false;
descriptors = xnmalloc (nfiles + 1, sizeof *descriptors);
/* Move all the names `up' one in the argv array to make room for
the entry for standard output. This writes into argv[argc]. */
for (i = nfiles; i >= 1; i--)
files[i] = files[i - 1];
if (O_BINARY && ! isatty (STDIN_FILENO))
xfreopen (NULL, "rb", stdin);
if (O_BINARY && ! isatty (STDOUT_FILENO))
xfreopen (NULL, "wb", stdout);
fadvise (stdin, FADVISE_SEQUENTIAL);
/* In the array of NFILES + 1 descriptors, make
the first one correspond to standard output. */
descriptors[0] = stdout;
files[0] = _("standard output");
setvbuf (stdout, NULL, _IONBF, 0);
for (i = 1; i <= nfiles; i++)
{
descriptors[i] = (STREQ (files[i], "-")
? stdout
: fopen (files[i], mode_string));
if (descriptors[i] == NULL)
{
error (0, errno, "%s", files[i]);
ok = false;
}
else
setvbuf (descriptors[i], NULL, _IONBF, 0);
}
if(nfiles == 0) {
/* special case: only stdout */
while (1)
{
bytes_read = read (0, buffer, sizeof buffer);
#ifdef EINTR
if (bytes_read < 0 && errno == EINTR)
continue;
#endif
if (bytes_read <= 0)
break;
if(!no_stdout) {
if (descriptors[0]
&& fwrite (buffer, bytes_read, 1, descriptors[0]) != 1)
{
error (0, errno, "%s", files[0]);
descriptors[0] = NULL;
ok = false;
}
}
}
}
else {
i = 1;
while (1)
{
/* Write to all NFILES + 1 descriptors.
Standard output is the first one. */
has_entire_line = true;
bytes_read = read(0, buffer, sizeof buffer);
if (bytes_read < 0 && errno == EINTR)
{
continue;
}
if (bytes_read <= 0) {
break;
}
remain = bytes_read;
ptr = buffer;
do {
if(next_ptr = (char*)memchr(ptr, '\n', min(remain, (sizeof buffer) - (ptr - buffer))) ) {
next_ptr++;
len = (size_t) (next_ptr - ptr);
has_entire_line = true;
}
else {
len = min(remain, (sizeof buffer) - (ptr - buffer));
has_entire_line = false;
}
if(!no_stdout) {
if (descriptors[0]
&& fwrite(ptr, len, 1, descriptors[0]) != 1)
{
error (0, errno, "%s", files[0]);
descriptors[0] = NULL;
ok = false;
}
}
if (descriptors[i]
&& fwrite (ptr, len, 1, descriptors[i]) != 1)
{
error (0, errno, "%s", files[i]);
descriptors[i] = NULL;
ok = false;
}
ptr = next_ptr;
if(has_entire_line) {
/* Did read an entire line, print next line to next descriptor */
i++;
if(i > nfiles) {
i = 1;
}
}
remain -= len;
} while(has_entire_line && remain > 0);
}
}
if (bytes_read == -1)
{
error (0, errno, _("read error"));
ok = false;
}
/* Close the files, but not standard output. */
for (i = 1; i <= nfiles; i++)
if (!STREQ (files[i], "-")
&& descriptors[i] && fclose (descriptors[i]) != 0)
{
error (0, errno, "%s", files[i]);
ok = false;
}
free (descriptors);
return ok;
}