/* Functions for communicating with a remote tape drive.
- Copyright 1988, 1992, 1994, 1996, 1997, 1999 Free Software Foundation, Inc.
+
+ Copyright 1988, 1992, 1994, 1996, 1997, 1999, 2000, 2001, 2004 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
code, courtesy of Dan Kegel. */
#include "system.h"
-
-#include "basename.h"
-#include "safe-read.h"
+#include "common.h"
+#include <safe-read.h>
+#include <full-write.h>
/* Try hard to get EOPNOTSUPP defined. 486/ISC has it in net/errno.h,
3B2/SVR3 has it in sys/inet.h. Otherwise, like on MSDOS, use EINVAL. */
#include "rmt.h"
-/* FIXME: Just to shut up -Wall. */
-int rexec ();
-
/* Exit status if exec errors. */
#define EXIT_ON_EXEC_ERROR 128
char *rmt_path__;
\f
-/*----------------------------------------------------------------------.
-| Close remote tape connection HANDLE, and reset errno to ERRNO_VALUE. |
-`----------------------------------------------------------------------*/
-
+/* Close remote tape connection HANDLE, and reset errno to ERRNO_VALUE. */
static void
_rmt_shutdown (int handle, int errno_value)
{
close (WRITE_SIDE (handle));
READ_SIDE (handle) = -1;
WRITE_SIDE (handle) = -1;
- errno = errno_value; /* FIXME: errno should be read-only */
+ errno = errno_value;
}
-/*-------------------------------------------------------------------------.
-| Attempt to perform the remote tape command specified in BUFFER on remote |
-| tape connection HANDLE. Return 0 if successful, -1 on error. |
-`-------------------------------------------------------------------------*/
-
+/* Attempt to perform the remote tape command specified in BUFFER on
+ remote tape connection HANDLE. Return 0 if successful, -1 on
+ error. */
static int
do_command (int handle, const char *buffer)
{
- size_t length;
- RETSIGTYPE (*pipe_handler) ();
-
/* Save the current pipe handler and try to make the request. */
- pipe_handler = signal (SIGPIPE, SIG_IGN);
- length = strlen (buffer);
- if (full_write (WRITE_SIDE (handle), buffer, length) == length)
- {
- signal (SIGPIPE, pipe_handler);
- return 0;
- }
+ size_t length = strlen (buffer);
+ RETSIGTYPE (*pipe_handler) () = signal (SIGPIPE, SIG_IGN);
+ ssize_t written = full_write (WRITE_SIDE (handle), buffer, length);
+ signal (SIGPIPE, pipe_handler);
+
+ if (written == length)
+ return 0;
/* Something went wrong. Close down and go home. */
- signal (SIGPIPE, pipe_handler);
_rmt_shutdown (handle, EIO);
return -1;
}
if (*cursor == 'E' || *cursor == 'F')
{
- errno = atoi (cursor + 1); /* FIXME: errno should be read-only */
-
/* Skip the error message line. */
/* FIXME: there is better to do than merely ignoring error messages
break;
}
+ errno = atoi (cursor + 1);
+
if (*cursor == 'F')
_rmt_shutdown (handle, errno);
return cursor + 1;
}
-/*----------------------------------------------------------------------.
-| Read and return the status from remote tape connection HANDLE. If an |
-| error occurred, return -1 and set errno. |
-`----------------------------------------------------------------------*/
-
-static long
+/* Read and return the status from remote tape connection HANDLE. If
+ an error occurred, return -1 and set errno. */
+static long int
get_status (int handle)
{
char command_buffer[COMMAND_BUFFER_SIZE];
const char *status = get_status_string (handle, command_buffer);
- return status ? atol (status) : -1L;
+ if (status)
+ {
+ long int result = atol (status);
+ if (0 <= result)
+ return result;
+ errno = EIO;
+ }
+ return -1;
}
static off_t
for (; *status == ' ' || *status == '\t'; status++)
continue;
-
+
negative = *status == '-';
status += negative || *status == '+';
-
+
for (;;)
{
int digit = *status++ - '0';
#if WITH_REXEC
-/*-------------------------------------------------------------------------.
-| Execute /etc/rmt as user USER on remote system HOST using rexec. Return |
-| a file descriptor of a bidirectional socket for stdin and stdout. If |
-| USER is zero, use the current username. |
-| |
-| By default, this code is not used, since it requires that the user have |
-| a .netrc file in his/her home directory, or that the application |
-| designer be willing to have rexec prompt for login and password info. |
-| This may be unacceptable, and .rhosts files for use with rsh are much |
-| more common on BSD systems. |
-`-------------------------------------------------------------------------*/
+/* Execute /etc/rmt as user USER on remote system HOST using rexec.
+ Return a file descriptor of a bidirectional socket for stdin and
+ stdout. If USER is zero, use the current username.
+ By default, this code is not used, since it requires that the user
+ have a .netrc file in his/her home directory, or that the
+ application designer be willing to have rexec prompt for login and
+ password info. This may be unacceptable, and .rhosts files for use
+ with rsh are much more common on BSD systems. */
static int
_rmt_rexec (char *host, char *user)
{
default: abort ();
}
+#ifdef O_APPEND
if (oflag & O_APPEND) strcat (buf, "|O_APPEND");
+#endif
if (oflag & O_CREAT) strcat (buf, "|O_CREAT");
#ifdef O_DSYNC
if (oflag & O_DSYNC) strcat (buf, "|O_DSYNC");
if (oflag & O_TRUNC) strcat (buf, "|O_TRUNC");
}
-/*------------------------------------------------------------------------.
-| Open a file (a magnetic tape device?) on the system specified in PATH, |
-| as the given user. PATH has the form `[USER@]HOST:FILE'. OPEN_MODE is |
-| O_RDONLY, O_WRONLY, etc. If successful, return the remote pipe number |
-| plus BIAS. REMOTE_SHELL may be overridden. On error, return -1. |
-`------------------------------------------------------------------------*/
-
+/* Open a file (a magnetic tape device?) on the system specified in
+ PATH, as the given user. PATH has the form `[USER@]HOST:FILE'.
+ OPEN_MODE is O_RDONLY, O_WRONLY, etc. If successful, return the
+ remote pipe number plus BIAS. REMOTE_SHELL may be overridden. On
+ error, return -1. */
int
rmt_open__ (const char *path, int open_mode, int bias, const char *remote_shell)
{
if (remote_pipe_number == MAXUNIT)
{
- errno = EMFILE; /* FIXME: errno should be read-only */
+ errno = EMFILE;
return -1;
}
close (from_remote[remote_pipe_number][PREAD]);
close (from_remote[remote_pipe_number][PWRITE]);
-#if !MSDOS
- setuid (getuid ());
- setgid (getgid ());
-#endif
+ sys_reset_uid_gid ();
if (remote_user)
execl (remote_shell, remote_shell_basename, remote_host,
return remote_pipe_number + bias;
}
-/*----------------------------------------------------------------.
-| Close remote tape connection HANDLE and shut down. Return 0 if |
-| successful, -1 on error. |
-`----------------------------------------------------------------*/
-
+/* Close remote tape connection HANDLE and shut down. Return 0 if
+ successful, -1 on error. */
int
rmt_close__ (int handle)
{
- int status;
+ long int status;
if (do_command (handle, "C\n") == -1)
return -1;
return status;
}
-/*-------------------------------------------------------------------------.
-| Read up to LENGTH bytes into BUFFER from remote tape connection HANDLE. |
-| Return the number of bytes read on success, -1 on error. |
-`-------------------------------------------------------------------------*/
-
-ssize_t
+/* Read up to LENGTH bytes into BUFFER from remote tape connection HANDLE.
+ Return the number of bytes read on success, SAFE_READ_ERROR on error. */
+size_t
rmt_read__ (int handle, char *buffer, size_t length)
{
char command_buffer[COMMAND_BUFFER_SIZE];
- ssize_t status, rlen;
+ size_t status;
+ size_t rlen;
size_t counter;
sprintf (command_buffer, "R%lu\n", (unsigned long) length);
if (do_command (handle, command_buffer) == -1
- || (status = get_status (handle)) == -1)
- return -1;
+ || (status = get_status (handle)) == SAFE_READ_ERROR)
+ return SAFE_READ_ERROR;
for (counter = 0; counter < status; counter += rlen, buffer += rlen)
{
rlen = safe_read (READ_SIDE (handle), buffer, status - counter);
- if (rlen <= 0)
+ if (rlen == SAFE_READ_ERROR || rlen == 0)
{
_rmt_shutdown (handle, EIO);
- return -1;
+ return SAFE_READ_ERROR;
}
}
return status;
}
-/*-------------------------------------------------------------------------.
-| Write LENGTH bytes from BUFFER to remote tape connection HANDLE. Return |
-| the number of bytes written on success, -1 on error. |
-`-------------------------------------------------------------------------*/
-
-ssize_t
+/* Write LENGTH bytes from BUFFER to remote tape connection HANDLE.
+ Return the number of bytes written. */
+size_t
rmt_write__ (int handle, char *buffer, size_t length)
{
char command_buffer[COMMAND_BUFFER_SIZE];
RETSIGTYPE (*pipe_handler) ();
+ size_t written;
sprintf (command_buffer, "W%lu\n", (unsigned long) length);
if (do_command (handle, command_buffer) == -1)
- return -1;
+ return 0;
pipe_handler = signal (SIGPIPE, SIG_IGN);
- if (full_write (WRITE_SIDE (handle), buffer, length) == length)
+ written = full_write (WRITE_SIDE (handle), buffer, length);
+ signal (SIGPIPE, pipe_handler);
+ if (written == length)
{
- signal (SIGPIPE, pipe_handler);
- return get_status (handle);
+ long int r = get_status (handle);
+ if (r < 0)
+ return 0;
+ if (r == length)
+ return length;
+ written = r;
}
/* Write error. */
- signal (SIGPIPE, pipe_handler);
_rmt_shutdown (handle, EIO);
- return -1;
+ return written;
}
-/*------------------------------------------------------------------------.
-| Perform an imitation lseek operation on remote tape connection HANDLE. |
-| Return the new file offset if successful, -1 if on error. |
-`------------------------------------------------------------------------*/
-
+/* Perform an imitation lseek operation on remote tape connection
+ HANDLE. Return the new file offset if successful, -1 if on error. */
off_t
rmt_lseek__ (int handle, off_t offset, int whence)
{
uintmax_t u = offset < 0 ? - (uintmax_t) offset : (uintmax_t) offset;
char *p = operand_buffer + sizeof operand_buffer;
+ *--p = 0;
do
*--p = '0' + (int) (u % 10);
while ((u /= 10) != 0);
return get_status_off (handle);
}
-/*-----------------------------------------------------------------------.
-| Perform a raw tape operation on remote tape connection HANDLE. Return |
-| the results of the ioctl, or -1 on error. |
-`-----------------------------------------------------------------------*/
-
+/* Perform a raw tape operation on remote tape connection HANDLE.
+ Return the results of the ioctl, or -1 on error. */
int
rmt_ioctl__ (int handle, int operation, char *argument)
{
switch (operation)
{
default:
- errno = EOPNOTSUPP; /* FIXME: errno should be read-only */
+ errno = EOPNOTSUPP;
return -1;
#ifdef MTIOCTOP
? - (uintmax_t) ((struct mtop *) argument)->mt_count
: (uintmax_t) ((struct mtop *) argument)->mt_count);
char *p = operand_buffer + sizeof operand_buffer;
-
+
+ *--p = 0;
do
*--p = '0' + (int) (u % 10);
while ((u /= 10) != 0);
case MTIOCGET:
{
ssize_t status;
- ssize_t counter;
+ size_t counter;
/* Grab the status and read it directly into the structure. This
assumes that the status buffer is not padded and that 2 shorts
for (; status > 0; status -= counter, argument += counter)
{
counter = safe_read (READ_SIDE (handle), argument, status);
- if (counter <= 0)
+ if (counter == SAFE_READ_ERROR || counter == 0)
{
_rmt_shutdown (handle, EIO);
return -1;
projects / chaz / tar / blobdiff