write_common.c

   1 /*
   2  * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file write_common.c common functions of para_audiod and para_write */
   8
   9 #include "para.h"
  10 #include "string.h"
  11 #include "list.h"
  12 #include "sched.h"
  13 #include "write.h"
  14 #include "error.h"
  15
  16 /** the array containing the names of all supported writers */
  17 const char *writer_names[] ={WRITER_NAMES};
  18
  19 /** the array of supported writers */
  20 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
  21
  22 static void wng_pre_select(__a_unused struct sched *s, struct task *t)
  23 {
  24         struct writer_node_group *g = t->private_data;
  25         int i;
  26
  27         FOR_EACH_WRITER_NODE(i, g) {
  28                 struct writer_node *wn = &g->writer_nodes[i];
  29                 t->ret = wn->writer->pre_select(s, wn);
  30                 if (t->ret < 0) {
  31                         g->eof = 1;
  32                         return;
  33                 }
  34         }
  35 }
  36
  37 static void wng_post_select(struct sched *s, struct task *t)
  38 {
  39         struct writer_node_group *g = t->private_data;
  40         int i;
  41         size_t min_written = 0;
  42
  43         FOR_EACH_WRITER_NODE(i, g) {
  44                 struct writer_node *wn = &g->writer_nodes[i];
  45                 t->ret = wn->writer->post_select(s, wn);
  46                 if (t->ret < 0) {
  47                         g->eof = 1;
  48                         return;
  49                 }
  50                 if (!i)
  51                         min_written = wn->written;
  52                 else
  53                         min_written = PARA_MIN(min_written, wn->written);
  54         }
  55 //      PARA_INFO_LOG("loaded: %zd, min_written: %zd bytes\n", *g->loaded, min_written);
  56         if (min_written) {
  57                 *g->loaded -= min_written;
  58                 FOR_EACH_WRITER_NODE(i, g)
  59                         g->writer_nodes[i].written -= min_written;
  60         }
  61         if (!*g->loaded && *g->input_eof) {
  62                 g->eof = 1;
  63                 t->ret = -E_WNG_EOF;
  64                 return;
  65         }
  66         t->ret = 1;
  67         if (*g->loaded && min_written) {
  68 //              PARA_INFO_LOG("moving %zd bytes\n", *g->loaded);
  69                 memmove(g->buf, g->buf + min_written, *g->loaded);
  70         }
  71 }
  72
  73 /**
  74  * call the open function of each writer in the group
  75  *
  76  * \param g the writer node group
  77  *
  78  * \return If at least one open function returned an error, all successful
  79  * writer notes get closed and this error value is returned. Upon success, a
  80  * task associated with \a g is registered to the scheduler and the function
  81  * returnes a positive value.
  82  * */
  83 int wng_open(struct writer_node_group *g)
  84 {
  85         int i, ret = 1;
  86
  87         PARA_NOTICE_LOG("opening wng %p with %d writer(s)\n", g, g->num_writers);
  88         register_task(&g->task);
  89         FOR_EACH_WRITER_NODE(i, g) {
  90                 struct writer_node *wn = &g->writer_nodes[i];
  91                 wn->wng = g;
  92                 ret = wn->writer->open(wn);
  93                 if (ret < 0)
  94                         goto err_out;
  95                 wn->chunk_bytes = ret;
  96                 g->max_chunk_bytes = PARA_MAX(g->max_chunk_bytes, ret);
  97         }
  98         sprintf(g->task.status, "%s", "writer node group");
  99         g->eof = 0;
 100         return 1;
 101 err_out:
 102         PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
 103         unregister_task(&g->task);
 104         while (i > 0) {
 105                 struct writer_node *wn = &g->writer_nodes[--i];
 106                 wn->writer->close(wn);
 107         }
 108         g->num_writers = 0;
 109         g->eof = 1;
 110         return ret;
 111 }
 112
 113
 114 /**
 115  * unregister a writer node group task
 116  *
 117  * \param g the group whose task is to be closed
 118  */
 119 void wng_unregister(struct writer_node_group *g)
 120 {
 121         unregister_task(&g->task);
 122         g->eof = 1;
 123 }
 124
 125 /**
 126  * call the close function of each writer in the given group
 127  *
 128  * \param g the writer node group to close
 129  *
 130  * This function also frees all resources of the given group.
 131  */
 132 void wng_close(struct writer_node_group *g)
 133 {
 134         int i;
 135
 136         if (!g)
 137                 return;
 138         PARA_NOTICE_LOG("closing wng with %d writer(s)\n", g->num_writers);
 139         FOR_EACH_WRITER_NODE(i, g) {
 140                 struct writer_node *wn = &g->writer_nodes[i];
 141                 wn->writer->close(wn);
 142         }
 143         free(g->writer_nodes);
 144         free(g);
 145 }
 146
 147 /**
 148  * allocate and initialize a new writer_node_group struct
 149  *
 150  * \param num_writers the number of writer nodes for the new group
 151  *
 152  * \return Pointer to the new writer node group
 153  */
 154 struct writer_node_group *wng_new(unsigned num_writers)
 155 {
 156         struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
 157         g->num_writers = num_writers;
 158         g->writer_nodes = para_calloc(num_writers
 159                 * sizeof(struct writer_node));
 160         g->task.private_data = g;
 161         g->task.post_select = wng_post_select;
 162         g->task.pre_select = wng_pre_select;
 163         return g;
 164 }
 165
 166 /**
 167  * call the init function of each supported paraslash writer
 168  */
 169 void init_supported_writers(void)
 170 {
 171         int i;
 172
 173         FOR_EACH_WRITER(i)
 174                 writers[i].init(&writers[i]);
 175 }
 176 /**
 177  * check if given string is a valid command line for any writer
 178  *
 179  * \param \wa string of the form writer_name:options
 180  * \param writer_num contains the number of the writer upon success
 181  *
 182  * This function checks whether \a wa starts with the name of a supported
 183  * paraslash writer, optinally followed by a colon and any options for that
 184  * writer.  If a valid writer name was found and further are present, the
 185  * remaining part of \a wa is passed to that writer's config parser.
 186  *
 187  * \return On success, a pointer to the gengetopt args info struct is returned
 188  * and \a writer_num contains the number of the writer. Otherwise this function
 189  * returns \p NULL.
 190  */
 191 void *check_writer_arg(const char *wa, int *writer_num)
 192 {
 193         int i;
 194
 195         *writer_num = -E_WRITE_COMMON_SYNTAX;
 196         PARA_INFO_LOG("checking  %s\n", wa);
 197         FOR_EACH_WRITER(i) {
 198                 const char *name = writer_names[i];
 199                 size_t len = strlen(name);
 200                 char c;
 201                 if (strlen(wa) < len)
 202                         continue;
 203                 if (strncmp(name, wa, len))
 204                         continue;
 205                 c = wa[len];
 206                 if (c && c != ' ')
 207                         continue;
 208                 if (c && !writers[i].parse_config)
 209                         return NULL;
 210                 *writer_num = i;
 211                 return writers[i].parse_config(c? wa + len + 1 : "");
 212         }
 213         PARA_ERROR_LOG("%s", "writer not found\n");
 214         return NULL;
 215 }
 216
 217 /**
 218  * setup a writer node group with only one writer, the default writer
 219  *
 220  * The writer which is set up depends on the OS. It defaults to alsa for Linux,
 221  * osx_write for OS X, file writer if neither of these is supported.
 222  *
 223  * \return pointer to the allocated writer node group
 224  */
 225 struct writer_node_group *setup_default_wng(void)
 226 {
 227         struct writer_node_group *wng = wng_new(1);
 228         wng->writer_nodes[0].writer = &writers[DEFAULT_WRITER];
 229         PARA_INFO_LOG("using default writer: %s %p\n",
 230                 writer_names[DEFAULT_WRITER], writers[DEFAULT_WRITER].parse_config);
 231         wng->writer_nodes[0].conf = writers[DEFAULT_WRITER].parse_config("");
 232         return wng;
 233 }