X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=fd.c;h=ed61664545817d51774bdff4d1502a019f8bdfe8;hb=c458b9d45e7c6ddda6285fca3797fddff815bd0a;hp=ec174ff69ed768645bd92705d1384b0cc074ea06;hpb=07c25fac868f7122ca38da3cf9bf6637ba18214a;p=paraslash.git

diff --git a/fd.c b/fd.c
index ec174ff6..ed616645 100644
--- a/fd.c
+++ b/fd.c
@@ -1,28 +1,18 @@
 /*
  * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
  *
- *     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 2 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, write to the Free Software
- *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
 /** \file fd.c helper functions for file descriptor handling */
 
-#include "para.h"
+#include <sys/types.h>
+#include <dirent.h>
 #include <sys/mman.h>
 #include <fcntl.h>
 #include <sys/select.h>
 
+#include "para.h"
 #include "error.h"
 /**
  * check whether a file exists
@@ -70,19 +60,20 @@ int para_select(int n, fd_set *readfds, fd_set *writefds,
 }
 
 /**
- * set a file descriptor to non-blocking mode
+ * Set a file descriptor to non-blocking mode.
  *
- * \param fd The file descriptor
+ * \param fd The file descriptor.
  *
- * \returns 1 on success, -E_F_GETFL, -E_F_SETFL, on errors.
+ * \return Standard.
  */
 int mark_fd_nonblock(int fd)
 {
 	int flags = fcntl(fd, F_GETFL);
 	if (flags < 0)
-		return -E_F_GETFL;
-	if (fcntl(fd, F_SETFL, ((long)flags) | O_NONBLOCK) < 0)
-		return -E_F_SETFL;
+		return -ERRNO_TO_PARA_ERROR(errno);
+	flags = fcntl(fd, F_SETFL, ((long)flags) | O_NONBLOCK);
+	if (flags < 0)
+		return -ERRNO_TO_PARA_ERROR(errno);
 	return 1;
 }
 
@@ -146,7 +137,7 @@ again:
 }
 
 /**
- * *paraslash's wrapper for mmap
+ * Paraslash's wrapper for mmap.
  *
  * \param length number of bytes to mmap
  * \param prot either PROT_NONE or the bitwise OR of one or more of
@@ -169,3 +160,122 @@ void *para_mmap(size_t length, int prot, int flags, int fd, off_t offset)
 	exit(EXIT_FAILURE);
 }
 
+/**
+ * Wrapper for the open(2) system call.
+ *
+ * \param path The filename.
+ * \param flags The usual open(2) flags.
+ * \param mode Specifies the permissions to use.
+ *
+ * The mode parameter must be specified when O_CREAT is in the flags, and is ignored
+ * otherwise.
+ *
+ * \return The file descriptor on success, negative on errors.
+ *
+ * \sa open(2).
+ */
+int para_open(const char *path, int flags, mode_t mode)
+{
+	int ret = open(path, flags, mode);
+
+	if (ret >= 0)
+		return ret;
+	return -ERRNO_TO_PARA_ERROR(errno);
+}
+
+/**
+ * Wrapper for chdir(2).
+ *
+ * \param path the specified directory.
+ *
+ * \return Positive on success, negative on errors.
+ */
+int para_chdir(const char *path)
+{
+	int ret = chdir(path);
+
+	if (ret >= 0)
+		return 1;
+	return -ERRNO_TO_PARA_ERROR(errno);
+}
+
+/**
+ * Save the cwd and open a given directory.
+ *
+ * \param dirname Path to the directory to open.
+ * \param dir Result pointer.
+ * \param cwd File descriptor of the current working directory.
+ *
+ * \return Positive on success, negative on errors.
+ *
+ * Opening the current directory (".") and calling fchdir() to return is
+ * usually faster and more reliable than saving cwd in some buffer and calling
+ * chdir() afterwards.
+ *
+ * If \a cwd is not \p NULL "." is opened and the resulting file descriptor is
+ * stored in \a cwd. If the function returns success, and \a cwd is not \p
+ * NULL, the caller must close this file descriptor (probably after calling
+ * fchdir(*cwd)).
+ *
+ * On errors, the function undos everything, so the caller needs neither close
+ * any files, nor change back to the original working directory.
+ *
+ * \sa getcwd(3).
+ *
+ */
+int para_opendir(const char *dirname, DIR **dir, int *cwd)
+{
+	int ret;
+
+	if (cwd) {
+		ret = para_open(".", O_RDONLY, 0);
+		if (ret < 0)
+			return ret;
+		*cwd = ret;
+	}
+	ret = para_chdir(dirname);
+	if (ret < 0)
+		goto close_cwd;
+	ret = -E_OPENDIR;
+	*dir = opendir(".");
+	if (!*dir)
+		goto change_to_orig_dir;
+	return 1;
+/* Ignore return value of fchdir() and close(). We're busted anyway. */
+change_to_orig_dir:
+	if (cwd)
+		fchdir(*cwd);
+close_cwd:
+	if (cwd)
+		close(*cwd);
+	return ret;
+}
+
+/**
+ * A wrapper for fchdir().
+ *
+ * \param fd An open file descriptor
+ *
+ * \return Positive on success, negative on errors.
+ */
+int para_fchdir(int fd)
+{
+	if (fchdir(fd) < 0)
+		return -E_FCHDIR;
+	return 1;
+}
+
+/**
+ * A wrapper for mkdir(2).
+ *
+ * \param path Name of the directory to create.
+ * \param mode The permissions to use.
+ *
+ * \return Standard.
+ */
+int para_mkdir(const char *path, mode_t mode)
+{
+	if (!mkdir(path, mode))
+		return 1;
+	return -ERRNO_TO_PARA_ERROR(errno);
+}