/*
- * Buffering to output and input.
+ * Buffering to output and input.
* Copyright (C) 1998 Kunihiro Ishiguro
*
* This file is part of GNU Zebra.
* 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 GNU Zebra; see the file COPYING. If not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * You should have received a copy of the GNU General Public License along
+ * with this program; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _ZEBRA_BUFFER_H
#define _ZEBRA_BUFFER_H
-/* Buffer master. */
-struct buffer
-{
- /* Data list. */
- struct buffer_data *head;
- struct buffer_data *tail;
-
- /* XXX: These unsigned longs should be size_t's */
- /* Current allocated data. */
- unsigned long alloc;
-
- /* Size of each buffer_data chunk. */
- unsigned long size;
-
- /* For allocation. */
- struct buffer_data *unused_head;
- struct buffer_data *unused_tail;
-
- /* Current total length of this buffer. */
- unsigned long length;
-};
-
-/* Data container. */
-struct buffer_data
-{
- struct buffer_data *next;
- struct buffer_data *prev;
-
- /* Current pointer. */
- unsigned long cp;
-
- /* Start pointer. */
- unsigned long sp;
-
- /* Actual data stream (variable length). */
- unsigned char data[0]; /* real dimension is buffer->size */
-};
-
-/* Buffer prototypes. */
-struct buffer *buffer_new (size_t);
-int buffer_write (struct buffer *, const void *, size_t);
-void buffer_free (struct buffer *);
-char *buffer_getstr (struct buffer *);
-int buffer_putc (struct buffer *, u_char);
-int buffer_putstr (struct buffer *, const char *);
-void buffer_reset (struct buffer *);
-int buffer_flush_all (struct buffer *, int);
-int buffer_flush_vty_all (struct buffer *, int, int, int);
-int buffer_flush_window (struct buffer *, int, int, int, int, int);
-int buffer_empty (struct buffer *);
-
-/* buffer_flush_available attempts to flush the queued data to the given
- file descriptor. It returns 0 if the buffers are now empty (after
- flushing), or 1 if more data remains on the buffer queue (must be flushed
- later). This function (unlike the other buffer_flush* functions) is
- designed to work with non-blocking file descriptors. */
-int buffer_flush_available(struct buffer *, int fd);
+/* Create a new buffer. Memory will be allocated in chunks of the given
+ size. If the argument is 0, the library will supply a reasonable
+ default size suitable for buffering socket I/O. */
+extern struct buffer *buffer_new(size_t);
+
+/* Free all data in the buffer. */
+extern void buffer_reset(struct buffer *);
+
+/* This function first calls buffer_reset to release all buffered data.
+ Then it frees the struct buffer itself. */
+extern void buffer_free(struct buffer *);
+
+/* Add the given data to the end of the buffer. */
+extern void buffer_put(struct buffer *, const void *, size_t);
+/* Add a single character to the end of the buffer. */
+extern void buffer_putc(struct buffer *, uint8_t);
+/* Add a NUL-terminated string to the end of the buffer. */
+extern void buffer_putstr(struct buffer *, const char *);
+/* Add given data, inline-expanding \n to \r\n */
+extern void buffer_put_crlf(struct buffer *b, const void *p, size_t size);
+
+/* Combine all accumulated (and unflushed) data inside the buffer into a
+ single NUL-terminated string allocated using XMALLOC(MTYPE_TMP). Note
+ that this function does not alter the state of the buffer, so the data
+ is still inside waiting to be flushed. */
+char *buffer_getstr(struct buffer *);
+
+/* Returns 1 if there is no pending data in the buffer. Otherwise returns 0. */
+int buffer_empty(struct buffer *);
+
+typedef enum {
+ /* An I/O error occurred. The buffer should be destroyed and the
+ file descriptor should be closed. */
+ BUFFER_ERROR = -1,
+
+ /* The data was written successfully, and the buffer is now empty
+ (there is no pending data waiting to be flushed). */
+ BUFFER_EMPTY = 0,
+
+ /* There is pending data in the buffer waiting to be flushed. Please
+ try flushing the buffer when select indicates that the file
+ descriptor
+ is writeable. */
+ BUFFER_PENDING = 1
+} buffer_status_t;
+
+/* Try to write this data to the file descriptor. Any data that cannot
+ be written immediately is added to the buffer queue. */
+extern buffer_status_t buffer_write(struct buffer *, int fd, const void *,
+ size_t);
+
+/* This function attempts to flush some (but perhaps not all) of
+ the queued data to the given file descriptor. */
+extern buffer_status_t buffer_flush_available(struct buffer *, int fd);
+
+/* The following 2 functions (buffer_flush_all and buffer_flush_window)
+ are for use in lib/vty.c only. They should not be used elsewhere. */
+
+/* Call buffer_flush_available repeatedly until either all data has been
+ flushed, or an I/O error has been encountered, or the operation would
+ block. */
+extern buffer_status_t buffer_flush_all(struct buffer *, int fd);
+
+/* Attempt to write enough data to the given fd to fill a window of the
+ given width and height (and remove the data written from the buffer).
+
+ If !no_more, then a message saying " --More-- " is appended.
+ If erase is true, then first overwrite the previous " --More-- " message
+ with spaces.
+
+ Any write error (including EAGAIN or EINTR) will cause this function
+ to return -1 (because the logic for handling the erase and more features
+ is too complicated to retry the write later).
+*/
+extern buffer_status_t buffer_flush_window(struct buffer *, int fd, int width,
+ int height, int erase, int no_more);
#endif /* _ZEBRA_BUFFER_H */
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