write_common.c

   1 /*
   2  * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     This program is distributed in the hope that it will be useful,
  10  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *     GNU General Public License for more details.
  13  *
  14  *     You should have received a copy of the GNU General Public License
  15  *     along with this program; if not, write to the Free Software
  16  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18
  19 /** \file write_common.c common functions of para_audiod and para_write */
  20
  21 #include "para.h"
  22 #include "string.h"
  23 #include "list.h"
  24 #include "sched.h"
  25 #include "write.h"
  26 #include "error.h"
  27
  28 /** the array containing the names of all supported writers */
  29 const char *writer_names[] ={WRITER_NAMES};
  30
  31 /** the array of supported writers */
  32 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
  33
  34 static void wng_pre_select(__a_unused struct sched *s, struct task *t)
  35 {
  36         struct writer_node_group *g = t->private_data;
  37         int i;
  38
  39         FOR_EACH_WRITER_NODE(i, g) {
  40                 struct writer_node *wn = &g->writer_nodes[i];
  41                 t->ret = wn->writer->pre_select(s, wn);
  42                 if (t->ret < 0) {
  43                         g->eof = 1;
  44                         return;
  45                 }
  46         }
  47 }
  48
  49 static void wng_post_select(struct sched *s, struct task *t)
  50 {
  51         struct writer_node_group *g = t->private_data;
  52         int i;
  53         size_t min_written = 0;
  54
  55         FOR_EACH_WRITER_NODE(i, g) {
  56                 struct writer_node *wn = &g->writer_nodes[i];
  57                 t->ret = wn->writer->post_select(s, wn);
  58                 if (t->ret < 0) {
  59                         g->eof = 1;
  60                         return;
  61                 }
  62                 if (!i)
  63                         min_written = wn->written;
  64                 else
  65                         min_written = PARA_MIN(min_written, wn->written);
  66         }
  67 //      PARA_INFO_LOG("loaded: %zd, min_written: %zd bytes\n", *g->loaded, min_written);
  68         if (min_written) {
  69                 *g->loaded -= min_written;
  70                 FOR_EACH_WRITER_NODE(i, g)
  71                         g->writer_nodes[i].written -= min_written;
  72         }
  73         if (!*g->loaded && *g->input_eof) {
  74                 g->eof = 1;
  75                 t->ret = -E_WNG_EOF;
  76                 return;
  77         }
  78         t->ret = 1;
  79         if (*g->loaded && min_written) {
  80 //              PARA_INFO_LOG("moving %zd bytes\n", *g->loaded);
  81                 memmove(g->buf, g->buf + min_written, *g->loaded);
  82         }
  83 }
  84
  85 /**
  86  * call the open function of each writer in the group
  87  *
  88  * \param g the writer node group
  89  *
  90  * \return If at least one open function returned an error, all successful
  91  * writer notes get closed and this error value is returned. Upon success, a
  92  * task associated with \a g is registered to the scheduler and the function
  93  * returnes a positive value.
  94  * */
  95 int wng_open(struct writer_node_group *g)
  96 {
  97         int i, ret = 1;
  98
  99         PARA_NOTICE_LOG("opening wng %p with %d writer(s)\n", g, g->num_writers);
 100         register_task(&g->task);
 101         FOR_EACH_WRITER_NODE(i, g) {
 102                 struct writer_node *wn = &g->writer_nodes[i];
 103                 wn->wng = g;
 104                 ret = wn->writer->open(wn);
 105                 if (ret < 0)
 106                         goto err_out;
 107                 wn->chunk_bytes = ret;
 108                 g->max_chunk_bytes = PARA_MAX(g->max_chunk_bytes, ret);
 109         }
 110         sprintf(g->task.status, "%s", "writer node group");
 111         g->eof = 0;
 112         return 1;
 113 err_out:
 114         unregister_task(&g->task);
 115         while (i > 0) {
 116                 struct writer_node *wn = &g->writer_nodes[--i];
 117                 wn->writer->close(wn);
 118         }
 119         g->num_writers = 0;
 120         g->eof = 1;
 121         return ret;
 122 }
 123
 124
 125 /**
 126  * unregister a writer node group task
 127  *
 128  * \param g the group whose task is to be closed
 129  */
 130 void wng_unregister(struct writer_node_group *g)
 131 {
 132         unregister_task(&g->task);
 133         g->eof = 1;
 134 }
 135
 136 /**
 137  * call the close function of each writer in the given group
 138  *
 139  * \param g the writer node group to close
 140  *
 141  * This function also frees all resources of the given group.
 142  */
 143 void wng_close(struct writer_node_group *g)
 144 {
 145         int i;
 146
 147         if (!g)
 148                 return;
 149         PARA_NOTICE_LOG("closing wng with %d writer(s)\n", g->num_writers);
 150         FOR_EACH_WRITER_NODE(i, g) {
 151                 struct writer_node *wn = &g->writer_nodes[i];
 152                 wn->writer->close(wn);
 153         }
 154         free(g->writer_nodes);
 155         free(g);
 156 }
 157
 158 /**
 159  * allocate and initialize a new writer_node_group struct
 160  *
 161  * \param num_writers the number of writer nodes for the new group
 162  *
 163  * \return Pointer to the new writer node group
 164  */
 165 struct writer_node_group *wng_new(unsigned num_writers)
 166 {
 167         struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
 168         g->num_writers = num_writers;
 169         g->writer_nodes = para_calloc(num_writers
 170                 * sizeof(struct writer_node));
 171         g->task.private_data = g;
 172         g->task.post_select = wng_post_select;
 173         g->task.pre_select = wng_pre_select;
 174         return g;
 175 }
 176
 177 /**
 178  * call the init function of each supported paraslash writer
 179  */
 180 void init_supported_writers(void)
 181 {
 182         int i;
 183
 184         FOR_EACH_WRITER(i)
 185                 writers[i].init(&writers[i]);
 186 }
 187 /**
 188  * check if given string is a valid command line for any writer
 189  *
 190  * \param \wa string of the form writer_name:options
 191  * \param writer_num contains the number of the writer upon success
 192  *
 193  * This function checks whether \a wa starts with the name of a supported
 194  * paraslash writer, optinally followed by a colon and any options for that
 195  * writer.  If a valid writer name was found and further are present, the
 196  * remaining part of \a wa is passed to that writer's config parser.
 197  *
 198  * \return On success, a pointer to the gengetopt args info struct is returned
 199  * and \a writer_num contains the number of the writer. Otherwise this function
 200  * returns \p NULL.
 201  */
 202 void *check_writer_arg(const char *wa, int *writer_num)
 203 {
 204         int i;
 205
 206         *writer_num = -E_WRITE_COMMON_SYNTAX;
 207         PARA_INFO_LOG("checking  %s\n", wa);
 208         FOR_EACH_WRITER(i) {
 209                 const char *name = writer_names[i];
 210                 size_t len = strlen(name);
 211                 char c;
 212                 if (strlen(wa) < len)
 213                         continue;
 214                 if (strncmp(name, wa, len))
 215                         continue;
 216                 c = wa[len];
 217                 if (c && c != ' ')
 218                         continue;
 219                 if (c && !writers[i].parse_config)
 220                         return NULL;
 221                 *writer_num = i;
 222                 return writers[i].parse_config(c? wa + len + 1 : "");
 223         }
 224         PARA_ERROR_LOG("%s", "writer not found\n");
 225         return NULL;
 226 }
 227
 228 /**
 229  * setup a writer node group with only one writer, the default writer
 230  *
 231  * The writer which is set up depends on the OS. It defaults to alsa for Linux,
 232  * osx_write for OS X, file writer if neither of these is supported.
 233  *
 234  * \return pointer to the allocated writer node group
 235  */
 236 struct writer_node_group *setup_default_wng(void)
 237 {
 238         struct writer_node_group *wng = wng_new(1);
 239         wng->writer_nodes[0].writer = &writers[DEFAULT_WRITER];
 240         PARA_INFO_LOG("using default writer: %s %p\n",
 241                 writer_names[DEFAULT_WRITER], writers[DEFAULT_WRITER].parse_config);
 242         wng->writer_nodes[0].conf = writers[DEFAULT_WRITER].parse_config("");
 243         return wng;
 244 }