fd: Open-code para_chdir().

[paraslash.git] / fd.c

diff --git a/fd.c b/fd.c
index 180032daa6d0f7bf11a63984480842b007c316c6..cc38f1afba150e0de41fff093c0c5b7ccb24e377 100644 (file)
--- a/fd.c
+++ b/fd.c
@@ -37,26 +37,27 @@ int xrename(const char *oldpath, const char *newpath)
 }
 
 /**
- * Write an array of buffers to a file descriptor.
+ * Write an array of buffers, handling non-fatal errors.
  *
- * \param fd The file descriptor.
+ * \param fd The file descriptor to write to.
  * \param iov Pointer to one or more buffers.
  * \param iovcnt The number of buffers.
  *
- * EAGAIN/EWOULDBLOCK is not considered a fatal error condition. For example
- * DCCP CCID3 has a sending wait queue which fills up and is emptied
- * asynchronously. The EAGAIN case means that there is currently no space in
- * the wait queue, but this can change at any moment.
+ * EAGAIN, EWOULDBLOCK and EINTR are not considered error conditions. If a
+ * write operation fails with EAGAIN or EWOULDBLOCK, the number of bytes that
+ * have been written so far is returned. In the EINTR case the operation is
+ * retried. Short writes are handled by issuing a subsequent write operation
+ * for the remaining part.
  *
  * \return Negative on fatal errors, number of bytes written else.
  *
  * For blocking file descriptors, this function returns either the sum of all
- * buffer sizes, or the error code of the fatal error that caused the last
- * write call to fail.
+ * buffer sizes or a negative error code which indicates the fatal error that
+ * caused a write call to fail.
  *
- * For nonblocking file descriptors there is a third possibility: Any positive
- * return value less than the sum of the buffer sizes indicates that some bytes
- * have been written but the next write would block.
+ * For nonblocking file descriptors there is a third possibility: Any
+ * non-negative return value less than the sum of the buffer sizes indicates
+ * that a write operation returned EAGAIN/EWOULDBLOCK.
  *
  * \sa writev(2), \ref xwrite().
  */
@@ -303,20 +304,6 @@ out:
        return ret;
 }
 
-/**
- * Check whether a file exists.
- *
- * \param fn The file name.
- *
- * \return True iff file exists.
- */
-bool file_exists(const char *fn)
-{
-       struct stat statbuf;
-
-       return !stat(fn, &statbuf);
-}
-
 /**
  * Set a file descriptor to blocking mode.
  *
@@ -405,22 +392,6 @@ int para_open(const char *path, int flags, mode_t mode)
        return -ERRNO_TO_PARA_ERROR(errno);
 }
 
-/**
- * Wrapper for chdir(2).
- *
- * \param path The specified directory.
- *
- * \return Standard.
- */
-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.
  *
@@ -456,9 +427,10 @@ static int para_opendir(const char *dirname, DIR **dir, int *cwd)
                        return ret;
                *cwd = ret;
        }
-       ret = para_chdir(dirname);
-       if (ret < 0)
+       if (chdir(dirname) != 0) {
+               ret = -ERRNO_TO_PARA_ERROR(errno);
                goto close_cwd;
+       }
        *dir = opendir(".");
        if (*dir)
                return 1;