apps/irssi/src/core/write-buffer.c

   1 /*
   2  write-buffer.c : irssi
   3
   4     Copyright (C) 2001 Timo Sirainen
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21 #include "module.h"
  22 #include "signals.h"
  23 #include "commands.h"
  24 #include "settings.h"
  25 #include "write-buffer.h"
  26
  27 #define BUFFER_BLOCK_SIZE 2048
  28
  29 typedef struct {
  30         char *active_block;
  31         int active_block_pos;
  32
  33         GSList *blocks;
  34 } BUFFER_REC;
  35
  36 static GSList *empty_blocks;
  37 static GHashTable *buffers;
  38 static int block_count;
  39
  40 static int write_buffer_max_blocks;
  41 static int timeout_tag;
  42
  43 static void write_buffer_new_block(BUFFER_REC *rec)
  44 {
  45         char *block;
  46
  47         if (empty_blocks == NULL)
  48                 block = g_malloc(BUFFER_BLOCK_SIZE);
  49         else {
  50                 block = empty_blocks->data;
  51                 empty_blocks = g_slist_remove(empty_blocks, block);
  52         }
  53
  54         block_count++;
  55         rec->active_block = block;
  56         rec->active_block_pos = 0;
  57         rec->blocks = g_slist_append(rec->blocks, block);
  58 }
  59
  60 int write_buffer(int handle, const void *data, int size)
  61 {
  62         BUFFER_REC *rec;
  63         const char *cdata = data;
  64         int next_size;
  65
  66         if (write_buffer_max_blocks <= 0) {
  67                 /* no write buffer */
  68                 return write(handle, data, size);
  69         }
  70
  71         if (size <= 0)
  72                 return size;
  73
  74         rec = g_hash_table_lookup(buffers, GINT_TO_POINTER(handle));
  75         if (rec == NULL) {
  76                 rec = g_new0(BUFFER_REC, 1);
  77                 write_buffer_new_block(rec);
  78                 g_hash_table_insert(buffers, GINT_TO_POINTER(handle), rec);
  79         }
  80
  81         while (size > 0) {
  82                 if (rec->active_block_pos == BUFFER_BLOCK_SIZE)
  83                         write_buffer_new_block(rec);
  84
  85                 next_size = size < BUFFER_BLOCK_SIZE-rec->active_block_pos ?
  86                         size : BUFFER_BLOCK_SIZE-rec->active_block_pos;
  87                 memcpy(rec->active_block+rec->active_block_pos,
  88                        cdata, next_size);
  89
  90                 rec->active_block_pos += next_size;
  91                 cdata += next_size;
  92                 size -= next_size;
  93         }
  94
  95         if (block_count > write_buffer_max_blocks)
  96                 write_buffer_flush();
  97
  98         return size;
  99 }
 100
 101 static int write_buffer_flush_rec(void *handlep, BUFFER_REC *rec)
 102 {
 103         GSList *tmp;
 104         int handle, size;
 105
 106         handle = GPOINTER_TO_INT(handlep);
 107         for (tmp = rec->blocks; tmp != NULL; tmp = tmp->next) {
 108                 size = tmp->data != rec->active_block ? BUFFER_BLOCK_SIZE :
 109                         rec->active_block_pos;
 110                 write(handle, tmp->data, size);
 111         }
 112
 113         empty_blocks = g_slist_concat(empty_blocks, rec->blocks);
 114         g_free(rec);
 115         return TRUE;
 116 }
 117
 118 void write_buffer_flush(void)
 119 {
 120         g_slist_foreach(empty_blocks, (GFunc) g_free, NULL);
 121         g_slist_free(empty_blocks);
 122         empty_blocks = NULL;
 123
 124         g_hash_table_foreach_remove(buffers,
 125                                     (GHRFunc) write_buffer_flush_rec, NULL);
 126         block_count = 0;
 127 }
 128
 129 static int flush_timeout(void)
 130 {
 131         write_buffer_flush();
 132         return 1;
 133 }
 134
 135 static void read_settings(void)
 136 {
 137         write_buffer_flush();
 138
 139         write_buffer_max_blocks =
 140                 settings_get_size("write_buffer_size") / BUFFER_BLOCK_SIZE;
 141
 142         if (settings_get_time("write_buffer_timeout") > 0) {
 143                 if (timeout_tag == -1) {
 144                         timeout_tag = g_timeout_add(settings_get_time("write_buffer_timeout"),
 145                                                     (GSourceFunc) flush_timeout,
 146                                                     NULL);
 147                 }
 148         } else if (timeout_tag != -1) {
 149                 g_source_remove(timeout_tag);
 150                 timeout_tag = -1;
 151         }
 152 }
 153
 154 static void cmd_flushbuffer(void)
 155 {
 156         write_buffer_flush();
 157 }
 158
 159 void write_buffer_init(void)
 160 {
 161         settings_add_time("misc", "write_buffer_timeout", "0");
 162         settings_add_size("misc", "write_buffer_size", "0");
 163
 164         buffers = g_hash_table_new((GHashFunc) g_direct_hash,
 165                                    (GCompareFunc) g_direct_equal);
 166
 167         empty_blocks = NULL;
 168         block_count = 0;
 169
 170         timeout_tag = -1;
 171         read_settings();
 172         signal_add("setup changed", (SIGNAL_FUNC) read_settings);
 173         command_bind("flushbuffer", NULL, (SIGNAL_FUNC) cmd_flushbuffer);
 174 }
 175
 176 void write_buffer_deinit(void)
 177 {
 178         if (timeout_tag != -1)
 179                 g_source_remove(timeout_tag);
 180
 181         write_buffer_flush();
 182         g_hash_table_destroy(buffers);
 183
 184         g_slist_foreach(empty_blocks, (GFunc) g_free, NULL);
 185         g_slist_free(empty_blocks);
 186
 187         signal_remove("setup changed", (SIGNAL_FUNC) read_settings);
 188         command_unbind("flushbuffer",  (SIGNAL_FUNC) cmd_flushbuffer);
 189 }