-/*
- * Copyright (C) 2006-2012 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file fd.c Helper functions for file descriptor handling. */
#include <sys/types.h>
#include <dirent.h>
#include <sys/mman.h>
-#include <fcntl.h>
-#include <sys/uio.h>
#include "para.h"
#include "error.h"
#include "string.h"
#include "fd.h"
+/**
+ * Change the name or location of a file.
+ *
+ * \param oldpath File to be moved.
+ * \param newpath Destination.
+ *
+ * This is just a simple wrapper for the rename(2) system call which returns a
+ * paraslash error code and prints an error message on failure.
+ *
+ * \return Standard.
+ *
+ * \sa rename(2).
+ */
+int xrename(const char *oldpath, const char *newpath)
+{
+ int ret = rename(oldpath, newpath);
+
+ if (ret >= 0)
+ return 1;
+ ret = -ERRNO_TO_PARA_ERROR(errno);
+ PARA_ERROR_LOG("failed to rename %s -> %s\n", oldpath, newpath);
+ return ret;
+}
+
/**
* Write an array of buffers to a file descriptor.
*
va_start(ap, fmt);
ret = xvasprintf(&msg, fmt, ap);
+ va_end(ap);
ret = write_all(fd, msg, ret);
free(msg);
return ret;
*
* If \a rfds is not \p NULL and the (non-blocking) file descriptor \a fd is
* not set in \a rfds, this function returns early without doing anything.
- * Otherwise The function tries to read up to \a sz bytes from \a fd. As for
- * xwrite(), EAGAIN is not considered an error condition. However, EOF
- * is.
+ * Otherwise The function tries to read up to \a sz bytes from \a fd, where \a
+ * sz is the sum of the lengths of all vectors in \a iov. As for xwrite(),
+ * \p EAGAIN is not considered an error condition. However, \p EOF is.
*
* \return Zero or a negative error code. If the underlying call to readv(2)
* returned zero (indicating an end of file condition) or failed for some
- * reason other than \p EAGAIN, a negative return value is returned.
+ * reason other than \p EAGAIN, a negative error code is returned.
*
* In any case, \a num_bytes contains the number of bytes that have been
* successfully read from \a fd (zero if the first readv() call failed with
*
* \param fn The file name.
*
- * \return Non-zero iff file exists.
+ * \return True iff file exists.
*/
-int file_exists(const char *fn)
+bool file_exists(const char *fn)
{
struct stat statbuf;
* This wrapper for FD_SET() passes its first two arguments to \p FD_SET. Upon
* return, \a max_fileno contains the maximum of the old_value and \a fd.
*
- * \sa para_select.
+ * \sa \ref para_select.
*/
void para_fd_set(int fd, fd_set *fds, int *max_fileno)
{
{
int ret;
+ *dir = NULL;
if (cwd) {
ret = para_open(".", O_RDONLY, 0);
if (ret < 0)
return ret;
}
-/**
- * A wrapper for fchdir().
- *
- * \param fd An open file descriptor.
- *
- * \return Standard.
- */
-static int para_fchdir(int fd)
-{
- if (fchdir(fd) < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- return 1;
-}
-
/**
* A wrapper for mkdir(2).
*
goto out;
}
*size = file_status.st_size;
+ /*
+ * If the file is empty, *size is zero and mmap() would return EINVAL
+ * (Invalid argument). This error is common enough to spend an extra
+ * error code which explicitly states the problem.
+ */
+ ret = -E_EMPTY;
+ if (*size == 0)
+ goto out;
+ /*
+ * If fd refers to a directory, mmap() returns ENODEV (No such device),
+ * at least on Linux. "Is a directory" seems to be more to the point.
+ */
+ ret = -ERRNO_TO_PARA_ERROR(EISDIR);
+ if (S_ISDIR(file_status.st_mode))
+ goto out;
+
ret = para_mmap(*size, mmap_prot, mmap_flags, fd, 0, map);
out:
if (ret < 0 || !fd_ptr)
*
* \return Standard.
*
- * \sa munmap(2), mmap_full_file().
+ * \sa munmap(2), \ref mmap_full_file().
*/
int para_munmap(void *start, size_t length)
{
*
* Common approach that opens /dev/null until it gets a file descriptor greater
* than two.
- *
- * \sa okir's Black Hats Manual.
*/
void valid_fd_012(void)
{
{
DIR *dir;
struct dirent *entry;
- int cwd_fd, ret2, ret = para_opendir(dirname, &dir, &cwd_fd);
+ int cwd_fd, ret = para_opendir(dirname, &dir, &cwd_fd);
if (ret < 0)
return ret == -ERRNO_TO_PARA_ERROR(EACCES)? 1 : ret;
ret = 1;
out:
closedir(dir);
- ret2 = para_fchdir(cwd_fd);
- if (ret2 < 0 && ret >= 0)
- ret = ret2;
+ if (fchdir(cwd_fd) < 0 && ret >= 0)
+ ret = -ERRNO_TO_PARA_ERROR(errno);
close(cwd_fd);
return ret;
}