I wasn't too sure why 'tee' used streams to be honest. It looks like
it was for an option that was never implemented:
commit 8ddf2904779fefb47e4caa68632341a22f18cffa
Author: Jim Meyering <[email protected]>
AuthorDate: Mon Jul 26 07:11:27 1999 +0000
Commit: Jim Meyering <[email protected]>
CommitDate: Mon Jul 26 07:11:27 1999 +0000
(tee): Convert from open/fds to using fopen/streams for
output, in preparation for addition of new compression option.
My main rationale for this patch though is to make it easier to
experiment with things like splice.
-- 8< --
We disable buffering on the streams anyways, so we were effectively
calling the write system call previously despite using streams.
* src/iopoll.h (fclose_wait, fwrite_wait): Remove declarations.
(close_wait, write_wait): Add declarations.
* src/iopoll.c (fwait_for_nonblocking_write, fclose_wait, fwrite_wait):
Remove functions.
(wait_for_nonblocking_write): New function based on
fwait_for_nonblocking_write.
(close_wait): New function based on fclose_wait.
(write_wait): New function based on fwrite_wait.
* src/tee.c: Include fcntl--.h. Don't include stdio--.h.
(get_next_out): Operate on file descriptors instead of streams.
(fail_output): Likewise. Remove clearerr call since we no longer call
fwrite on stdout.
(tee_files): Operate on file descriptors instead of streams. Remove
calls to setvbuf.
---
src/iopoll.c | 53 ++++++++++++++++++++++++----------------------------
src/iopoll.h | 4 ++--
src/tee.c | 40 ++++++++++++++++-----------------------
3 files changed, 42 insertions(+), 55 deletions(-)
diff --git a/src/iopoll.c b/src/iopoll.c
index 5d87839a3..ff4e223ac 100644
--- a/src/iopoll.c
+++ b/src/iopoll.c
@@ -177,62 +177,57 @@ iopoll_output_ok (int fdout)
Return true, if EAGAIN has been successfully handled. */
static bool
-fwait_for_nonblocking_write (FILE *f)
+wait_for_nonblocking_write (int fd)
{
if (! IS_EAGAIN (errno))
/* non-recoverable write error */
return false;
- int fd = fileno (f);
- if (fd == -1)
- goto fail;
-
/* wait for the file descriptor to become writable */
if (iopoll_internal (-1, fd, true, false) != 0)
- goto fail;
+ {
+ errno = EAGAIN;
+ return false;
+ }
/* successfully waited for the descriptor to become writable */
- clearerr (f);
return true;
-
-fail:
- errno = EAGAIN;
- return false;
}
-
-/* wrapper for fclose() that also waits for F if non blocking. */
+/* wrapper for close() that also waits for FD if non blocking. */
extern bool
-fclose_wait (FILE *f)
+close_wait (int fd)
{
- for (;;)
- {
- if (fflush (f) == 0)
- break;
-
- if (! fwait_for_nonblocking_write (f))
- break;
- }
-
- return fclose (f) == 0;
+ while (wait_for_nonblocking_write (fd))
+ ;
+ return close (fd) == 0;
}
-/* wrapper for fwrite() that also waits for F if non blocking. */
+/* wrapper for write() that also waits for FD if non blocking. */
extern bool
-fwrite_wait (char const *buf, ssize_t size, FILE *f)
+write_wait (int fd, void const *buffer, size_t size)
{
- for (;;)
+ unsigned char const *buf = buffer;
+
+ while (true)
{
- const size_t written = fwrite (buf, 1, size, f);
+ ssize_t written = write (fd, buf, size);
+ if (written < 0)
+ {
+ if (errno == EINTR)
+ continue;
+ written = 0;
+ }
+
size -= written;
affirm (size >= 0);
if (size <= 0) /* everything written */
return true;
- if (! fwait_for_nonblocking_write (f))
+ if (! wait_for_nonblocking_write (fd))
return false;
buf += written;
diff --git a/src/iopoll.h b/src/iopoll.h
index 0177a4d25..1711fdab9 100644
--- a/src/iopoll.h
+++ b/src/iopoll.h
@@ -5,5 +5,5 @@ int iopoll (int fdin, int fdout, bool block);
bool iopoll_input_ok (int fdin);
bool iopoll_output_ok (int fdout);
-bool fclose_wait (FILE *f);
-bool fwrite_wait (char const *buf, ssize_t size, FILE *f);
+bool close_wait (int fd);
+bool write_wait (int fd, void const *buffer, size_t size);
diff --git a/src/tee.c b/src/tee.c
index ffd4b20ec..32a18e340 100644
--- a/src/tee.c
+++ b/src/tee.c
@@ -24,8 +24,8 @@
#include "system.h"
#include "argmatch.h"
#include "fadvise.h"
+#include "fcntl--.h"
#include "iopoll.h"
-#include "stdio--.h"
#include "xbinary-io.h"
#include "iopoll.h"
@@ -194,10 +194,10 @@ main (int argc, char **argv)
ATTRIBUTE_PURE
static int
-get_next_out (FILE **descriptors, int nfiles, int idx)
+get_next_out (int *descriptors, int nfiles, int idx)
{
for (idx++; idx <= nfiles; idx++)
- if (descriptors[idx])
+ if (0 <= descriptors[idx])
return idx;
return -1; /* no outputs remaining */
}
@@ -206,21 +206,19 @@ get_next_out (FILE **descriptors, int nfiles, int idx)
Return true if this indicates a reportable error. */
static bool
-fail_output (FILE **descriptors, char **files, int i)
+fail_output (int *descriptors, char **files, int i)
{
int w_errno = errno;
bool fail = errno != EPIPE
|| output_error == output_error_exit
|| output_error == output_error_warn;
- if (descriptors[i] == stdout)
- clearerr (stdout); /* Avoid redundant close_stdout diagnostic. */
if (fail)
{
error (output_error == output_error_exit
|| output_error == output_error_exit_nopipe,
w_errno, "%s", quotef (files[i]));
}
- descriptors[i] = NULL;
+ descriptors[i] = -1;
return fail;
}
@@ -233,16 +231,13 @@ static bool
tee_files (int nfiles, char **files, bool pipe_check)
{
size_t n_outputs = 0;
- FILE **descriptors;
+ int *descriptors;
bool *out_pollable IF_LINT ( = NULL);
char buffer[BUFSIZ];
ssize_t bytes_read = 0;
int first_out = 0; /* idx of first non-null output in descriptors */
bool ok = true;
- char const *mode_string =
- (O_BINARY
- ? (append ? "ab" : "wb")
- : (append ? "a" : "w"));
+ int flags = O_WRONLY | O_CREAT | O_BINARY | (append ? O_APPEND : O_TRUNC);
xset_binary_mode (STDIN_FILENO, O_BINARY);
xset_binary_mode (STDOUT_FILENO, O_BINARY);
@@ -255,18 +250,17 @@ tee_files (int nfiles, char **files, bool pipe_check)
if (pipe_check)
out_pollable = xnmalloc (nfiles + 1, sizeof *out_pollable);
files--;
- descriptors[0] = stdout;
+ descriptors[0] = STDOUT_FILENO;
if (pipe_check)
- out_pollable[0] = iopoll_output_ok (fileno (descriptors[0]));
+ out_pollable[0] = iopoll_output_ok (descriptors[0]);
files[0] = bad_cast (_("standard output"));
- setvbuf (stdout, NULL, _IONBF, 0);
n_outputs++;
for (int i = 1; i <= nfiles; i++)
{
/* Do not treat "-" specially - as mandated by POSIX. */
- descriptors[i] = fopen (files[i], mode_string);
- if (descriptors[i] == NULL)
+ descriptors[i] = open (files[i], flags, MODE_RW_UGO);
+ if (descriptors[i] < 0)
{
if (pipe_check)
out_pollable[i] = false;
@@ -278,8 +272,7 @@ tee_files (int nfiles, char **files, bool pipe_check)
else
{
if (pipe_check)
- out_pollable[i] = iopoll_output_ok (fileno (descriptors[i]));
- setvbuf (descriptors[i], NULL, _IONBF, 0);
+ out_pollable[i] = iopoll_output_ok (descriptors[i]);
n_outputs++;
}
}
@@ -289,8 +282,7 @@ tee_files (int nfiles, char **files, bool pipe_check)
if (pipe_check && out_pollable[first_out])
{
/* Monitor for input, or errors on first valid output. */
- int err = iopoll (STDIN_FILENO, fileno (descriptors[first_out]),
- true);
+ int err = iopoll (STDIN_FILENO, descriptors[first_out], true);
/* Close the output if it became a broken pipe. */
if (err == IOPOLL_BROKEN_OUTPUT)
@@ -318,8 +310,8 @@ tee_files (int nfiles, char **files, bool pipe_check)
/* Write to all NFILES + 1 descriptors.
Standard output is the first one. */
for (int i = 0; i <= nfiles; i++)
- if (descriptors[i]
- && ! fwrite_wait (buffer, bytes_read, descriptors[i]))
+ if (0 <= descriptors[i]
+ && ! write_wait (descriptors[i], buffer, bytes_read))
{
if (fail_output (descriptors, files, i))
ok = false;
@@ -337,7 +329,7 @@ tee_files (int nfiles, char **files, bool pipe_check)
/* Close the files, but not standard output. */
for (int i = 1; i <= nfiles; i++)
- if (descriptors[i] && ! fclose_wait (descriptors[i]))
+ if (0 <= descriptors[i] && ! close_wait (descriptors[i]))
{
error (0, errno, "%s", quotef (files[i]));
ok = false;
--
2.53.0
