write_common.c

   1 /*
   2  * Copyright (C) 2006-2009 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 <regex.h>
  10
  11 #include "para.h"
  12 #include "string.h"
  13 #include "list.h"
  14 #include "sched.h"
  15 #include "ggo.h"
  16 #include "write.h"
  17 #include "error.h"
  18
  19 /** the array containing the names of all supported writers */
  20 const char *writer_names[] ={WRITER_NAMES};
  21
  22 /** the array of supported writers */
  23 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
  24
  25 static void wng_pre_select(struct sched *s, struct task *t)
  26 {
  27         struct writer_node_group *g = container_of(t, struct writer_node_group, task);
  28         int i;
  29
  30         FOR_EACH_WRITER_NODE(i, g) {
  31                 struct writer_node *wn = &g->writer_nodes[i];
  32                 struct writer *w = writers + wn->writer_num;
  33                 if (!w->pre_select)
  34                         continue;
  35                 t->error = w->pre_select(s, wn);
  36                 if (t->error < 0)
  37                         return;
  38         }
  39         /*
  40          * Force a minimal delay if something was written during the previous
  41          * call to wng_post_select(). This is necessary because the filter
  42          * chain might still have data for us which it couldn't convert during
  43          * the previous run due to its buffer size constraints. In this case we
  44          * do not want to wait until the next input data arrives as this could
  45          * lead to buffer underruns.
  46          */
  47         if (g->last_written == 0)
  48                 return;
  49         s->timeout.tv_sec = 0;
  50         s->timeout.tv_usec = 1;
  51 }
  52
  53 static void wng_post_select(struct sched *s, struct task *t)
  54 {
  55         struct writer_node_group *g = container_of(t, struct writer_node_group, task);
  56         int i;
  57         size_t min_written = 0, max_written = 0;
  58
  59         FOR_EACH_WRITER_NODE(i, g) {
  60                 struct writer_node *wn = &g->writer_nodes[i];
  61                 struct writer *w = writers + wn->writer_num;
  62                 t->error = w->post_select(s, wn);
  63                 if (t->error < 0)
  64                         return;
  65                 if (!i)
  66                         min_written = wn->written;
  67                 else
  68                         min_written = PARA_MIN(min_written, wn->written);
  69                 max_written = PARA_MAX(max_written, wn->written);
  70         }
  71         g->last_written = max_written;
  72         //PARA_INFO_LOG("loaded: %zd, min_written: %zd bytes\n", *g->loaded, min_written);
  73         if (min_written) {
  74                 *g->loaded -= min_written;
  75                 FOR_EACH_WRITER_NODE(i, g)
  76                         g->writer_nodes[i].written -= min_written;
  77         }
  78         if (!*g->loaded && *g->input_error) {
  79                 t->error = *g->input_error;
  80                 return;
  81         }
  82         if (*g->loaded && min_written) {
  83 //              PARA_INFO_LOG("moving %zd bytes\n", *g->loaded);
  84                 memmove(*g->bufp, *g->bufp + min_written, *g->loaded);
  85         }
  86 }
  87
  88 /**
  89  * call the open function of each writer in the group
  90  *
  91  * \param g the writer node group
  92  *
  93  * \return If at least one open function returned an error, all successful
  94  * writer notes get closed and this error value is returned. Upon success, a
  95  * task associated with \a g is registered to the scheduler and the function
  96  * returns a positive value.
  97  * */
  98 int wng_open(struct writer_node_group *g)
  99 {
 100         int i, ret = 1;
 101
 102         PARA_NOTICE_LOG("opening wng %p with %d writer(s)\n", g, g->num_writers);
 103         FOR_EACH_WRITER_NODE(i, g) {
 104                 struct writer_node *wn = &g->writer_nodes[i];
 105                 struct writer *w = writers + wn->writer_num;
 106                 wn->wng = g;
 107                 ret = w->open(wn);
 108                 if (ret < 0)
 109                         goto err_out;
 110         }
 111         sprintf(g->task.status, "%s", "writer node group");
 112         register_task(&g->task);
 113         g->open = 1;
 114         return 1;
 115 err_out:
 116         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 117         while (i > 0) {
 118                 struct writer_node *wn = &g->writer_nodes[--i];
 119                 struct writer *w = writers + wn->writer_num;
 120                 w->close(wn);
 121         }
 122         free(g->writer_nodes);
 123         g->num_writers = 0;
 124         g->task.error = -E_TASK_UNREGISTERED;
 125         return ret;
 126 }
 127
 128 /**
 129  * call the close function of each writer in the given group
 130  *
 131  * \param g the writer node group to close
 132  *
 133  * This function also frees all resources of the given group.
 134  */
 135 void wng_close(struct writer_node_group *g)
 136 {
 137         int i;
 138
 139         if (!g || !g->open)
 140                 return;
 141         PARA_NOTICE_LOG("closing wng with %d writer(s)\n", g->num_writers);
 142         FOR_EACH_WRITER_NODE(i, g) {
 143                 struct writer_node *wn = &g->writer_nodes[i];
 144                 struct writer *w = writers + wn->writer_num;
 145                 w->close(wn);
 146         }
 147         free(g->writer_nodes);
 148         free(g);
 149 }
 150
 151 /**
 152  * allocate and initialize a new writer_node_group struct
 153  *
 154  * \param num_writers the number of writer nodes for the new group
 155  *
 156  * \return Pointer to the new writer node group
 157  */
 158 struct writer_node_group *wng_new(unsigned num_writers)
 159 {
 160         struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
 161         g->num_writers = num_writers;
 162         g->writer_nodes = para_calloc(num_writers
 163                 * sizeof(struct writer_node));
 164         g->task.post_select = wng_post_select;
 165         g->task.pre_select = wng_pre_select;
 166         return g;
 167 }
 168
 169 /**
 170  * Call the init function of each supported paraslash writer.
 171  */
 172 void writer_init(void)
 173 {
 174         int i;
 175
 176         FOR_EACH_WRITER(i)
 177                 writers[i].init(&writers[i]);
 178 }
 179 /**
 180  * check if given string is a valid command line for any writer
 181  *
 182  * \param \wa string of the form writer_name:options
 183  * \param writer_num contains the number of the writer upon success
 184  *
 185  * This function checks whether \a wa starts with the name of a supported
 186  * paraslash writer, optionally followed by a colon and any options for that
 187  * writer.  If a valid writer name was found and further are present, the
 188  * remaining part of \a wa is passed to that writer's config parser.
 189  *
 190  * \return On success, a pointer to the gengetopt args info struct is returned
 191  * and \a writer_num contains the number of the writer. Otherwise this function
 192  * returns \p NULL.
 193  */
 194 void *check_writer_arg(const char *wa, int *writer_num)
 195 {
 196         int i;
 197
 198         *writer_num = -E_WRITE_COMMON_SYNTAX;
 199         PARA_INFO_LOG("checking  %s\n", wa);
 200         FOR_EACH_WRITER(i) {
 201                 const char *name = writer_names[i];
 202                 size_t len = strlen(name);
 203                 char c;
 204                 if (strlen(wa) < len)
 205                         continue;
 206                 if (strncmp(name, wa, len))
 207                         continue;
 208                 c = wa[len];
 209                 if (c && c != ' ')
 210                         continue;
 211                 if (c && !writers[i].parse_config)
 212                         return NULL;
 213                 *writer_num = i;
 214                 return writers[i].parse_config(c? wa + len + 1 : "");
 215         }
 216         PARA_ERROR_LOG("writer not found\n");
 217         return NULL;
 218 }
 219
 220 /**
 221  * setup a writer node group with only one writer, the default writer
 222  *
 223  * The writer which is set up depends on the OS. It defaults to alsa for Linux,
 224  * osx_write for OS X, file writer if neither of these is supported.
 225  *
 226  * \return pointer to the allocated writer node group
 227  */
 228 struct writer_node_group *setup_default_wng(void)
 229 {
 230         struct writer_node_group *wng = wng_new(1);
 231         wng->writer_nodes[0].writer_num = DEFAULT_WRITER;
 232         PARA_INFO_LOG("using default writer: %s %p\n",
 233                 writer_names[DEFAULT_WRITER], writers[DEFAULT_WRITER].parse_config);
 234         wng->writer_nodes[0].conf = writers[DEFAULT_WRITER].parse_config("");
 235         return wng;
 236 }
 237 /**
 238  * Print the help text of all writers to stdout.
 239  *
 240  * \param detailed Whether to print the detailed help text.
 241  */
 242 void print_writer_helps(int detailed)
 243 {
 244         int i;
 245
 246         printf_or_die("\nAvailable writers: \n\t");
 247         FOR_EACH_WRITER(i)
 248                 printf_or_die("%s%s", i? " " : "", writer_names[i]);
 249         printf_or_die("\n\n");
 250         FOR_EACH_WRITER(i) {
 251                 struct writer *w = writers + i;
 252
 253                 if (!w->help.short_help)
 254                         continue;
 255                 printf_or_die("Options for %s:\n", writer_names[i]);
 256                 ggo_print_help(&w->help, detailed);
 257         }
 258 }