+2003-01-08 Bruno Haible <bruno@clisp.org>
+
+ * safe-read.h: Update from current gnulib version.
+ * safe-read.c: Update from current gnulib version.
+ * safe-write.h: Update from current gnulib version.
+ * safe-write.c: Update from current gnulib version.
+ * full-write.h: Update from current gnulib version.
+ * full-write.c: Update from current gnulib version.
+
2002-12-16 Bruno Haible <bruno@clisp.org>
* copy-file.c: Include <sys/utime.h> if <utime.h> doesn't exist.
-/* An interface to write() that writes all it is asked to write.
+/* An interface to read and write that retries (if necessary) until complete.
- Copyright (C) 1993, 1994, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
- Foundation, Inc.
+ Copyright (C) 1993, 1994, 1997-2003 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
#endif
/* Specification. */
-#include "full-write.h"
+#ifdef FULL_READ
+# include "full-read.h"
+#else
+# include "full-write.h"
+#endif
#include <errno.h>
#ifndef errno
extern int errno;
#endif
-#include "safe-write.h"
+#ifdef FULL_READ
+# include "safe-read.h"
+# define safe_rw safe_read
+# define full_rw full_read
+# undef const
+# define const /* empty */
+#else
+# include "safe-write.h"
+# define safe_rw safe_write
+# define full_rw full_write
+#endif
-/* Write COUNT bytes at BUF to descriptor FD, retrying if interrupted
- or if partial writes occur. Return the number of bytes successfully
- written, setting errno if that is less than COUNT. */
+#ifdef FULL_READ
+/* Set errno to zero upon EOF. */
+# define ZERO_BYTE_TRANSFER_ERRNO 0
+#else
+/* Some buggy drivers return 0 when one tries to write beyond
+ a device's end. (Example: Linux 1.2.13 on /dev/fd0.)
+ Set errno to ENOSPC so they get a sensible diagnostic. */
+# define ZERO_BYTE_TRANSFER_ERRNO ENOSPC
+#endif
+
+/* Write(read) COUNT bytes at BUF to(from) descriptor FD, retrying if
+ interrupted or if a partial write(read) occurs. Return the number
+ of bytes transferred.
+ When writing, set errno if fewer than COUNT bytes are written.
+ When reading, if fewer than COUNT bytes are read, you must examine
+ errno to distinguish failure from EOF (errno == 0). */
size_t
-full_write (int fd, const void *buf, size_t count)
+full_rw (int fd, const void *buf, size_t count)
{
- size_t total_written = 0;
+ size_t total = 0;
+ const char *ptr = buf;
- if (count > 0)
+ while (count > 0)
{
- const char *ptr = buf;
-
- do
+ size_t n_rw = safe_rw (fd, ptr, count);
+ if (n_rw == (size_t) -1)
+ break;
+ if (n_rw == 0)
{
- size_t written = safe_write (fd, ptr, count);
- if (written == (size_t)-1)
- break;
- if (written == 0)
- {
- /* Some buggy drivers return 0 when you fall off a device's
- end. (Example: Linux 1.2.13 on /dev/fd0.) */
- errno = ENOSPC;
- break;
- }
- total_written += written;
- ptr += written;
- count -= written;
+ errno = ZERO_BYTE_TRANSFER_ERRNO;
+ break;
}
- while (count > 0);
+ total += n_rw;
+ ptr += n_rw;
+ count -= n_rw;
}
- return total_written;
+ return total;
}
-/* An interface to read() that retries after interrupts.
- Copyright (C) 1993, 1994, 1998, 2002 Free Software Foundation, Inc.
+/* An interface to read and write that retries after interrupts.
+ Copyright (C) 1993, 1994, 1998, 2002-2003 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
#endif
/* Specification. */
-#include "safe-read.h"
+#ifdef SAFE_WRITE
+# include "safe-write.h"
+#else
+# include "safe-read.h"
+#endif
/* Get ssize_t. */
#include <sys/types.h>
extern int errno;
#endif
+#ifdef EINTR
+# define IS_EINTR(x) ((x) == EINTR)
+#else
+# define IS_EINTR(x) 0
+#endif
+
#include <limits.h>
-/* We don't pass an nbytes count > SSIZE_MAX to read() - POSIX says the
- effect would be implementation-defined. Also we don't pass an nbytes
- count > INT_MAX but <= SSIZE_MAX to read() - this triggers a bug in
- Tru64 5.1. */
-#define MAX_BYTES_TO_READ INT_MAX
+#ifndef CHAR_BIT
+# define CHAR_BIT 8
+#endif
+
+/* The extra casts work around common compiler bugs. */
+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+/* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
+ It is necessary at least when t == time_t. */
+#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
+ ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
+#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
-/* Read up to COUNT bytes at BUF from descriptor FD, retrying if interrupted.
- Return the actual number of bytes read, zero for EOF, or (size_t) -1
- for an error. */
+#ifndef INT_MAX
+# define INT_MAX TYPE_MAXIMUM (int)
+#endif
+
+#ifdef SAFE_WRITE
+# define safe_rw safe_write
+# define rw write
+#else
+# define safe_rw safe_read
+# define rw read
+# undef const
+# define const /* empty */
+#endif
+
+/* Read(write) up to COUNT bytes at BUF from(to) descriptor FD, retrying if
+ interrupted. Return the actual number of bytes read(written), zero for EOF,
+ or SAFE_READ_ERROR(SAFE_WRITE_ERROR) upon error. */
size_t
-safe_read (int fd, void *buf, size_t count)
+safe_rw (int fd, void const *buf, size_t count)
{
- size_t total_read = 0;
+ ssize_t result;
- if (count > 0)
+ /* POSIX limits COUNT to SSIZE_MAX, but we limit it further, requiring
+ that COUNT <= INT_MAX, to avoid triggering a bug in Tru64 5.1.
+ When decreasing COUNT, keep the file pointer block-aligned.
+ Note that in any case, read(write) may succeed, yet read(write)
+ fewer than COUNT bytes, so the caller must be prepared to handle
+ partial results. */
+ if (count > INT_MAX)
+ count = INT_MAX & ~8191;
+
+ do
{
- char *ptr = (char *) buf;
- do
- {
- size_t nbytes_to_read = count;
- ssize_t result;
-
- /* Limit the number of bytes to read in one round, to avoid running
- into unspecified behaviour. But keep the file pointer block
- aligned when doing so. */
- if (nbytes_to_read > MAX_BYTES_TO_READ)
- nbytes_to_read = MAX_BYTES_TO_READ & ~8191;
-
- result = read (fd, ptr, nbytes_to_read);
- if (result < 0)
- {
-#ifdef EINTR
- if (errno == EINTR)
- continue;
-#endif
- return result;
- }
- total_read += result;
- ptr += result;
- count -= result;
- }
- while (count > 0);
+ result = rw (fd, buf, count);
}
+ while (result < 0 && IS_EINTR (errno));
- return total_read;
+ return (size_t) result;
}
#include <stddef.h>
+#define SAFE_READ_ERROR ((size_t) -1)
+
/* Read up to COUNT bytes at BUF from descriptor FD, retrying if interrupted.
- Return the actual number of bytes read, zero for EOF, or (size_t) -1
- for an error. */
+ Return the actual number of bytes read, zero for EOF, or SAFE_READ_ERROR
+ upon error. */
extern size_t safe_read (int fd, void *buf, size_t count);
-/* An interface to write() that retries after interrupts.
- Copyright (C) 1993, 1994, 1998, 2002 Free Software Foundation, Inc.
+/* An interface to write that retries after interrupts.
+ Copyright (C) 2002 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
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-/* Specification. */
-#include "safe-write.h"
-
-/* Get ssize_t. */
-#include <sys/types.h>
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-#include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
-
-#include <limits.h>
-
-/* We don't pass an nbytes count > SSIZE_MAX to write() - POSIX says the
- effect would be implementation-defined. Also we don't pass an nbytes
- count > INT_MAX but <= SSIZE_MAX to write() - this triggers a bug in
- Tru64 5.1. */
-#define MAX_BYTES_TO_READ INT_MAX
-
-/* Write up to COUNT bytes at BUF to descriptor FD, retrying if interrupted.
- Return the actual number of bytes written, zero for EOF, or (size_t) -1
- for an error. */
-size_t
-safe_write (int fd, const void *buf, size_t count)
-{
- size_t total_written = 0;
-
- if (count > 0)
- {
- const char *ptr = (const char *) buf;
- do
- {
- size_t nbytes_to_write = count;
- ssize_t result;
-
- /* Limit the number of bytes to write in one round, to avoid running
- into unspecified behaviour. But keep the file pointer block
- aligned when doing so. */
- if (nbytes_to_write > MAX_BYTES_TO_READ)
- nbytes_to_write = MAX_BYTES_TO_READ & ~8191;
-
- result = write (fd, ptr, nbytes_to_write);
- if (result < 0)
- {
-#ifdef EINTR
- if (errno == EINTR)
- continue;
-#endif
- return result;
- }
- total_written += result;
- ptr += result;
- count -= result;
- }
- while (count > 0);
- }
-
- return total_written;
-}
+#define SAFE_WRITE
+#include "safe-read.c"
#include <stddef.h>
+#define SAFE_WRITE_ERROR ((size_t) -1)
+
/* Write up to COUNT bytes at BUF to descriptor FD, retrying if interrupted.
- Return the actual number of bytes written, zero for EOF, or (size_t) -1
- for an error. */
+ Return the actual number of bytes written, zero for EOF, or SAFE_WRITE_ERROR
+ upon error. */
extern size_t safe_write (int fd, const void *buf, size_t count);
projects / thirdparty / gettext.git / commitdiff
