libosmovty
0.9.3
Osmocom VTY library
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00001 /* 00002 * Buffering to output and input. 00003 * Copyright (C) 1998 Kunihiro Ishiguro 00004 * 00005 * This file is part of GNU Zebra. 00006 * 00007 * GNU Zebra is free software; you can redistribute it and/or modify 00008 * it under the terms of the GNU General Public License as published 00009 * by the Free Software Foundation; either version 2, or (at your 00010 * option) any later version. 00011 * 00012 * GNU Zebra is distributed in the hope that it will be useful, but 00013 * WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU General Public License 00018 * along with GNU Zebra; see the file COPYING. If not, write to the 00019 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 00020 * Boston, MA 02111-1307, USA. 00021 */ 00022 00023 #pragma once 00024 00025 #include <sys/types.h> 00026 00027 /* Create a new buffer. Memory will be allocated in chunks of the given 00028 size. If the argument is 0, the library will supply a reasonable 00029 default size suitable for buffering socket I/O. */ 00030 struct buffer *buffer_new(void *ctx, size_t); 00031 00032 /* Free all data in the buffer. */ 00033 void buffer_reset(struct buffer *); 00034 00035 /* This function first calls buffer_reset to release all buffered data. 00036 Then it frees the struct buffer itself. */ 00037 void buffer_free(struct buffer *); 00038 00039 /* Add the given data to the end of the buffer. */ 00040 extern void buffer_put(struct buffer *, const void *, size_t); 00041 /* Add a single character to the end of the buffer. */ 00042 extern void buffer_putc(struct buffer *, unsigned char); 00043 /* Add a NUL-terminated string to the end of the buffer. */ 00044 extern void buffer_putstr(struct buffer *, const char *); 00045 00046 /* Combine all accumulated (and unflushed) data inside the buffer into a 00047 single NUL-terminated string allocated using XMALLOC(MTYPE_TMP). Note 00048 that this function does not alter the state of the buffer, so the data 00049 is still inside waiting to be flushed. */ 00050 char *buffer_getstr(struct buffer *); 00051 00052 /* Returns 1 if there is no pending data in the buffer. Otherwise returns 0. */ 00053 int buffer_empty(struct buffer *); 00054 00055 typedef enum { 00056 /* An I/O error occurred. The buffer should be destroyed and the 00057 file descriptor should be closed. */ 00058 BUFFER_ERROR = -1, 00059 00060 /* The data was written successfully, and the buffer is now empty 00061 (there is no pending data waiting to be flushed). */ 00062 BUFFER_EMPTY = 0, 00063 00064 /* There is pending data in the buffer waiting to be flushed. Please 00065 try flushing the buffer when select indicates that the file descriptor 00066 is writeable. */ 00067 BUFFER_PENDING = 1 00068 } buffer_status_t; 00069 00070 /* Try to write this data to the file descriptor. Any data that cannot 00071 be written immediately is added to the buffer queue. */ 00072 extern buffer_status_t buffer_write(struct buffer *, int fd, 00073 const void *, size_t); 00074 00075 /* This function attempts to flush some (but perhaps not all) of 00076 the queued data to the given file descriptor. */ 00077 extern buffer_status_t buffer_flush_available(struct buffer *, int fd); 00078 00079 /* The following 2 functions (buffer_flush_all and buffer_flush_window) 00080 are for use in lib/vty.c only. They should not be used elsewhere. */ 00081 00082 /* Call buffer_flush_available repeatedly until either all data has been 00083 flushed, or an I/O error has been encountered, or the operation would 00084 block. */ 00085 extern buffer_status_t buffer_flush_all(struct buffer *, int fd); 00086 00087 /* Attempt to write enough data to the given fd to fill a window of the 00088 given width and height (and remove the data written from the buffer). 00089 00090 If !no_more, then a message saying " --More-- " is appended. 00091 If erase is true, then first overwrite the previous " --More-- " message 00092 with spaces. 00093 00094 Any write error (including EAGAIN or EINTR) will cause this function 00095 to return -1 (because the logic for handling the erase and more features 00096 is too complicated to retry the write later). 00097 */ 00098 extern buffer_status_t buffer_flush_window(struct buffer *, int fd, int width, 00099 int height, int erase, int no_more);