[disorder] / lib / queue.c

/*
 * This file is part of DisOrder.
 * Copyright (C) 2004, 2005, 2006 Richard Kettlewell
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#include <config.h>
#include "types.h"

#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <time.h>
#include <stddef.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>

#include "mem.h"
#include "queue.h"
#include "log.h"
#include "configuration.h"
#include "split.h"
#include "syscalls.h"
#include "charset.h"
#include "table.h"
#include "inputline.h"
#include "printf.h"
#include "plugin.h"
#include "basen.h"
#include "eventlog.h"
#include "disorder.h"

const char *playing_states[] = {
  "failed",
  "isscratch",
  "no_player",
  "ok",
  "paused",
  "quitting",
  "random",
  "scratched",
  "started",
  "unplayed"
};

/* the head of the queue is played next, so normally we add to the tail */
struct queue_entry qhead = { &qhead, &qhead, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

/* the head of the recent list is the oldest thing, the tail the most recently
 * played */
struct queue_entry phead = { &phead, &phead, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

static long pcount;

/* add new entry @n@ to a doubly linked list just after @b@ */
static void l_add(struct queue_entry *b, struct queue_entry *n) {
  n->prev = b;
  n->next = b->next;
  n->next->prev = n;
  n->prev->next = n;
}

/* remove an entry from a doubly-linked list */
static void l_remove(struct queue_entry *node) {
  node->next->prev = node->prev;
  node->prev->next = node->next;
}

#define VALUE(q, offset, type) *(type *)((char *)q + offset)

static int unmarshall_long(char *data, struct queue_entry *q,
			   size_t offset,
			   void (*error_handler)(const char *, void *),
			   void *u) {
  if(xstrtol(&VALUE(q, offset, long), data, 0, 0)) {
    error_handler(strerror(errno), u);
    return -1;
  }
  return 0;
}

static const char *marshall_long(const struct queue_entry *q, size_t offset) {
  char buffer[256];
  int n;

  n = byte_snprintf(buffer, sizeof buffer, "%ld", VALUE(q, offset, long));
  if(n < 0)
    fatal(errno, "error converting int");
  else if((size_t)n >= sizeof buffer)
    fatal(0, "long converted to decimal is too long");
  return xstrdup(buffer);
}

static int unmarshall_string(char *data, struct queue_entry *q,
			     size_t offset,
			     void attribute((unused)) (*error_handler)(const char *, void *),
			     void attribute((unused)) *u) {
  VALUE(q, offset, char *) = data;
  return 0;
}

static const char *marshall_string(const struct queue_entry *q, size_t offset) {
  return VALUE(q, offset, char *);
}

static int unmarshall_time_t(char *data, struct queue_entry *q,
			     size_t offset,
			     void (*error_handler)(const char *, void *),
			     void *u) {
  long_long ul;

  if(xstrtoll(&ul, data, 0, 0)) {
    error_handler(strerror(errno), u);
    return -1;
  }
  VALUE(q, offset, time_t) = ul;
  return 0;
}

static const char *marshall_time_t(const struct queue_entry *q, size_t offset) {
  char buffer[256];
  int n;

  n = byte_snprintf(buffer, sizeof buffer,
		    "%"PRIdMAX, (intmax_t)VALUE(q, offset, time_t));
  if(n < 0)
    fatal(errno, "error converting time");
  else if((size_t)n >= sizeof buffer)
    fatal(0, "time converted to decimal is too long");
  return xstrdup(buffer);
}

static int unmarshall_state(char *data, struct queue_entry *q,
			    size_t offset,
			    void (*error_handler)(const char *, void *),
			    void *u) {
  int n;

  if((n = table_find(playing_states, 0, sizeof (char *),
		     sizeof playing_states / sizeof *playing_states,
		     data)) < 0) {
    D(("state=[%s] n=%d", data, n));
    error_handler("invalid state", u);
    return -1;
  }
  VALUE(q, offset, enum playing_state) = n;
  return 0;
}

static const char *marshall_state(const struct queue_entry *q, size_t offset) {
  return playing_states[VALUE(q, offset, enum playing_state)];
}

#define F(n, h) { #n, offsetof(struct queue_entry, n), marshall_##h, unmarshall_##h }

static const struct field {
  const char *name;
  size_t offset;
  const char *(*marshall)(const struct queue_entry *q, size_t offset);
  int (*unmarshall)(char *data, struct queue_entry *q, size_t offset,
		    void (*error_handler)(const char *, void *),
		    void *u);
} fields[] = {
  /* Keep this table sorted. */
  F(expected, time_t),
  F(id, string),
  F(played, time_t),
  F(scratched, string),
  F(sofar, long),
  F(state, state),
  F(submitter, string),
  F(track, string),
  F(when, time_t),
  F(wstat, long)
};

int queue_unmarshall(struct queue_entry *q, const char *s,
		     void (*error_handler)(const char *, void *),
		     void *u) {
  char **vec;
  int nvec;

  if(!(vec = split(s, &nvec, SPLIT_QUOTES, error_handler, u)))
    return -1;
  return queue_unmarshall_vec(q, nvec, vec, error_handler, u);
}

int queue_unmarshall_vec(struct queue_entry *q, int nvec, char **vec,
			 void (*error_handler)(const char *, void *),
			 void *u) {
  int n;

  if(nvec % 2 != 0) {
    error_handler("invalid marshalled queue format", u);
    return -1;
  }
  while(*vec) {
    D(("key %s value %s", vec[0], vec[1]));
    if((n = TABLE_FIND(fields, struct field, name, *vec)) < 0) {
      error_handler("unknown key in queue data", u);
      return -1;
    } else {
      if(fields[n].unmarshall(vec[1], q, fields[n].offset, error_handler, u))
	return -1;
    }
    vec += 2;
  }
  return 0;
}

void queue_fix_sofar(struct queue_entry *q) {
  long sofar;
  
  /* Fake up SOFAR field for currently-playing tracks that don't have it filled
   * in by the speaker process.  XXX this horrible bodge should go away when we
   * have a more general implementation of pausing as that field will always
   * have to be right for the playing track. */
  if((q->state == playing_started
      || q->state == playing_paused)
     && q->type & DISORDER_PLAYER_PAUSES
     && (q->type & DISORDER_PLAYER_TYPEMASK) != DISORDER_PLAYER_RAW) {
    if(q->lastpaused) {
      if(q->uptopause == -1)		/* Don't know how far thru. */
	sofar = -1;
      else if(q->lastresumed)		/* Has been paused and resumed. */
	sofar = q->uptopause + time(0) - q->lastresumed;
      else				/* Currently paused. */
	sofar = q->uptopause;
    } else				/* Never been paused. */
      sofar = time(0) - q->played;
    q->sofar = sofar;
  }
}

char *queue_marshall(const struct queue_entry *q) {
  unsigned n;
  const char *vec[sizeof fields / sizeof *fields], *v;
  char *r, *s;
  size_t len = 1;

  for(n = 0; n < sizeof fields / sizeof *fields; ++n)
    if((v = fields[n].marshall(q, fields[n].offset))) {
      vec[n] = quoteutf8(v);
      len += strlen(vec[n]) + strlen(fields[n].name) + 2;
    } else
      vec[n] = 0;
  s = r = xmalloc_noptr(len);
  for(n = 0; n < sizeof fields / sizeof *fields; ++n)
    if(vec[n]) {
      *s++ = ' ';
      s += strlen(strcpy(s, fields[n].name));
      *s++ = ' ';
      s += strlen(strcpy(s, vec[n]));
    }
  return r;
}

static void queue_read_error(const char *msg,
			     void *u) {
  fatal(0, "error parsing queue %s: %s", (const char *)u, msg);
}

static void queue_do_read(struct queue_entry *head, const char *path) {
  char *buffer;
  FILE *fp;
  struct queue_entry *q;

  if(!(fp = fopen(path, "r"))) {
    if(errno == ENOENT)
      return;			/* no queue */
    fatal(errno, "error opening %s", path);
  }
  head->next = head->prev = head;
  while(!inputline(path, fp, &buffer, '\n')) {
    q = xmalloc(sizeof *q);
    queue_unmarshall(q, buffer, queue_read_error, (void *)path);
    if(head == &qhead
       && (!q->track
	   || !q->when))
      fatal(0, "incomplete queue entry in %s", path);
    l_add(head->prev, q);
  }
  if(ferror(fp)) fatal(errno, "error reading %s", path);
  fclose(fp);
}

void queue_read(void) {
  queue_do_read(&qhead, config_get_file("queue"));
}

void recent_read(void) {
  struct queue_entry *q;

  queue_do_read(&phead, config_get_file("recent"));
  /* reset pcount after loading */
  pcount = 0;
  q = phead.next;
  while(q != &phead) {
    ++pcount;
    q = q->next;
  }
}

static void queue_do_write(const struct queue_entry *head, const char *path) {
  char *tmp;
  FILE *fp;
  struct queue_entry *q;

  byte_xasprintf(&tmp, "%s.new", path);
  if(!(fp = fopen(tmp, "w"))) fatal(errno, "error opening %s", tmp);
  for(q = head->next; q != head; q = q->next)
    if(fprintf(fp, "%s\n", queue_marshall(q)) < 0)
      fatal(errno, "error writing %s", tmp);
  if(fclose(fp) < 0) fatal(errno, "error closing %s", tmp);
  if(rename(tmp, path) < 0) fatal(errno, "error replacing %s", path);
}

void queue_write(void) {
  queue_do_write(&qhead, config_get_file("queue"));
}

void recent_write(void) {
  queue_do_write(&phead, config_get_file("recent"));
}

void queue_id(struct queue_entry *q) {
  static unsigned long serial;
  unsigned long a[3];
  char buffer[128];

  a[0] = serial++ & 0xFFFFFFFFUL;
  a[1] = time(0) & 0xFFFFFFFFUL;
  a[2] = getpid() & 0xFFFFFFFFUL;
  basen(a, 3, buffer, sizeof buffer, 62);
  q->id = xstrdup(buffer);
}

struct queue_entry *queue_add(const char *track, const char *submitter,
			      int where) {
  struct queue_entry *q, *beforeme;

  q = xmalloc(sizeof *q);
  q->track = xstrdup(track);
  q->submitter = submitter ? xstrdup(submitter) : 0;
  q->state = playing_unplayed;
  queue_id(q);
  time(&q->when);
  switch(where) {
  case WHERE_START:
    l_add(&qhead, q);
    break;
  case WHERE_END:
    l_add(qhead.prev, q);
    break;
  case WHERE_BEFORE_RANDOM:
    /* We want to find the point in the queue before the block of random tracks
     * at the end. */
    beforeme = &qhead;
    while(beforeme->prev != &qhead
	  && beforeme->prev->state == playing_random)
      beforeme = beforeme->prev;
    l_add(beforeme->prev, q);
    break;
  }
  /* submitter will be a null pointer for a scratch */
  if(submitter)
    notify_queue(track, submitter);
  eventlog_raw("queue", queue_marshall(q), (const char *)0);
  return q;
}

int queue_move(struct queue_entry *q, int delta, const char *who) {
  int moved = 0;
  char buffer[20];

  /* not the most efficient approach but hopefuly relatively comprehensible:
   * the idea is that for each step we determine which nodes are affected, and
   * fill in all the links starting at the 'prev' end and moving towards the
   * 'next' end. */
  
  while(delta > 0 && q->prev != &qhead) {
    struct queue_entry *n, *p, *pp;

    n = q->next;
    p = q->prev;
    pp = p->prev;
    pp->next = q;
    q->prev = pp;
    q->next = p;
    p->prev = q;
    p->next = n;
    n->prev = p;
    --delta;
    ++moved;
  }

  while(delta < 0 && q->next != &qhead) {
    struct queue_entry *n, *p, *nn;

    p = q->prev;
    n = q->next;
    nn = n->next;
    p->next = n;
    n->prev = p;
    n->next = q;
    q->prev = n;
    q->next = nn;
    nn->prev = q;
    ++delta;
    --moved;
  }

  if(moved) {
    info("user %s moved %s", who, q->id);
    notify_queue_move(q->track, who);
    sprintf(buffer, "%d", moved);
    eventlog("moved", who, (char *)0);
  }
  
  return delta;
}

static int find_in_list(struct queue_entry *needle,
			int nqs, struct queue_entry **qs) {
  int n;

  for(n = 0; n < nqs; ++n)
    if(qs[n] == needle)
      return 1;
  return 0;
}

void queue_moveafter(struct queue_entry *target,
		     int nqs, struct queue_entry **qs,
		     const char *who) {
  struct queue_entry *q;
  int n;

  /* Normalize */
  if(!target)
    target = &qhead;
  else
    while(find_in_list(target, nqs, qs))
      target = target->prev;
  /* Do the move */
  for(n = 0; n < nqs; ++n) {
    q = qs[n];
    l_remove(q);
    l_add(target, q);
    target = q;
    /* Log the individual tracks */
    info("user %s moved %s", who, q->id);
    notify_queue_move(q->track, who);
  }
  /* Report that the queue changed to the event log */
  eventlog("moved", who, (char *)0);
}

void queue_remove(struct queue_entry *which, const char *who) {
  if(who) {
    info("user %s removed %s", who, which->id);
    notify_queue_move(which->track, who);
  }
  eventlog("removed", which->id, who, (const char *)0);
  l_remove(which);
}

struct queue_entry *queue_find(const char *key) {
  struct queue_entry *q;

  for(q = qhead.next;
      q != &qhead && strcmp(q->track, key) && strcmp(q->id, key);
      q = q->next)
    ;
  return q != &qhead ? q : 0;
}

void queue_played(struct queue_entry *q) {
  while(pcount && pcount >= config->history) {
    eventlog("recent_removed", phead.next->id, (char *)0);
    l_remove(phead.next);
    pcount--;
  }
  if(config->history) {
    eventlog_raw("recent_added", queue_marshall(q), (char *)0);
    l_add(phead.prev, q);
    ++pcount;
  }
}

/*
Local Variables:
c-basic-offset:2
comment-column:40
fill-column:79
End:
*/
Commit	Line	Data
460b9539	1	/*
	2	* This file is part of DisOrder.
	3	* Copyright (C) 2004, 2005, 2006 Richard Kettlewell
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
	18	* USA
	19	*/
	20
	21	#include <config.h>
	22	#include "types.h"
	23
	24	#include <string.h>
	25	#include <stdio.h>
	26	#include <errno.h>
	27	#include <stdlib.h>
	28	#include <time.h>
	29	#include <stddef.h>
	30	#include <sys/types.h>
	31	#include <sys/socket.h>
	32	#include <unistd.h>
	33
	34	#include "mem.h"
	35	#include "queue.h"
	36	#include "log.h"
	37	#include "configuration.h"
	38	#include "split.h"
	39	#include "syscalls.h"
	40	#include "charset.h"
	41	#include "table.h"
	42	#include "inputline.h"
	43	#include "printf.h"
	44	#include "plugin.h"
	45	#include "basen.h"
	46	#include "eventlog.h"
	47	#include "disorder.h"
	48
	49	const char *playing_states[] = {
	50	"failed",
	51	"isscratch",
	52	"no_player",
	53	"ok",
	54	"paused",
	55	"quitting",
	56	"random",
	57	"scratched",
	58	"started",
	59	"unplayed"
	60	};
	61
	62	/* the head of the queue is played next, so normally we add to the tail */
	63	struct queue_entry qhead = { &qhead, &qhead, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
	64
65	/* the head of the recent list is the oldest thing, the tail the most recently
66	* played */
67	struct queue_entry phead = { &phead, &phead, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
68
69	static long pcount;
70
71	/* add new entry @n@ to a doubly linked list just after @b@ */
72	static void l_add(struct queue_entry b, struct queue_entry n) {
73	n->prev = b;
74	n->next = b->next;
75	n->next->prev = n;
76	n->prev->next = n;
77	}
78
79	/* remove an entry from a doubly-linked list */
80	static void l_remove(struct queue_entry *node) {
81	node->next->prev = node->prev;
82	node->prev->next = node->next;
83	}
84
85	#define VALUE(q, offset, type) (type )((char *)q + offset)
86
87	static int unmarshall_long(char data, struct queue_entry q,
88	size_t offset,
89	void (error_handler)(const char , void *),
90	void *u) {
91	if(xstrtol(&VALUE(q, offset, long), data, 0, 0)) {
92	error_handler(strerror(errno), u);
93	return -1;
94	}
95	return 0;
96	}
97
98	static const char marshall_long(const struct queue_entry q, size_t offset) {
99	char buffer[256];
100	int n;
101
102	n = byte_snprintf(buffer, sizeof buffer, "%ld", VALUE(q, offset, long));
103	if(n < 0)
104	fatal(errno, "error converting int");
105	else if((size_t)n >= sizeof buffer)
106	fatal(0, "long converted to decimal is too long");
107	return xstrdup(buffer);
108	}
109
110	static int unmarshall_string(char data, struct queue_entry q,
111	size_t offset,
112	void attribute((unused)) (error_handler)(const char , void *),
113	void attribute((unused)) *u) {
114	VALUE(q, offset, char *) = data;
115	return 0;
116	}
117
118	static const char marshall_string(const struct queue_entry q, size_t offset) {
119	return VALUE(q, offset, char *);
120	}
121
122	static int unmarshall_time_t(char data, struct queue_entry q,
123	size_t offset,
124	void (error_handler)(const char , void *),
125	void *u) {
126	long_long ul;
127
128	if(xstrtoll(&ul, data, 0, 0)) {
129	error_handler(strerror(errno), u);
130	return -1;
131	}
132	VALUE(q, offset, time_t) = ul;
133	return 0;
134	}
135
136	static const char marshall_time_t(const struct queue_entry q, size_t offset) {
137	char buffer[256];
138	int n;
139
140	n = byte_snprintf(buffer, sizeof buffer,
141	"%"PRIdMAX, (intmax_t)VALUE(q, offset, time_t));
142	if(n < 0)
143	fatal(errno, "error converting time");
144	else if((size_t)n >= sizeof buffer)
145	fatal(0, "time converted to decimal is too long");
146	return xstrdup(buffer);
147	}
148
149	static int unmarshall_state(char data, struct queue_entry q,
150	size_t offset,
151	void (error_handler)(const char , void *),
152	void *u) {
153	int n;
154
155	if((n = table_find(playing_states, 0, sizeof (char *),
156	sizeof playing_states / sizeof *playing_states,
157	data)) < 0) {
158	D(("state=[%s] n=%d", data, n));
159	error_handler("invalid state", u);
160	return -1;
161	}
162	VALUE(q, offset, enum playing_state) = n;
163	return 0;
164	}
165
166	static const char marshall_state(const struct queue_entry q, size_t offset) {
167	return playing_states[VALUE(q, offset, enum playing_state)];
168	}
169
170	#define F(n, h) { #n, offsetof(struct queue_entry, n), marshall_##h, unmarshall_##h }
171
172	static const struct field {
173	const char *name;
174	size_t offset;
175	const char (marshall)(const struct queue_entry *q, size_t offset);
176	int (unmarshall)(char data, struct queue_entry *q, size_t offset,
177	void (error_handler)(const char , void *),
178	void *u);
179	} fields[] = {
180	/* Keep this table sorted. */
181	F(expected, time_t),
182	F(id, string),
183	F(played, time_t),
184	F(scratched, string),
185	F(sofar, long),
186	F(state, state),
187	F(submitter, string),
188	F(track, string),
189	F(when, time_t),
190	F(wstat, long)
191	};
192
193	int queue_unmarshall(struct queue_entry q, const char s,
194	void (error_handler)(const char , void *),
195	void *u) {
196	char **vec;
197	int nvec;
198
199	if(!(vec = split(s, &nvec, SPLIT_QUOTES, error_handler, u)))
200	return -1;
201	return queue_unmarshall_vec(q, nvec, vec, error_handler, u);
202	}
203
204	int queue_unmarshall_vec(struct queue_entry q, int nvec, char *vec,
205	void (error_handler)(const char , void *),
206	void *u) {
207	int n;
208
209	if(nvec % 2 != 0) {
210	error_handler("invalid marshalled queue format", u);
211	return -1;
212	}
213	while(*vec) {
214	D(("key %s value %s", vec[0], vec[1]));
215	if((n = TABLE_FIND(fields, struct field, name, *vec)) < 0) {
216	error_handler("unknown key in queue data", u);
217	return -1;
218	} else {
219	if(fields[n].unmarshall(vec[1], q, fields[n].offset, error_handler, u))
220	return -1;
221	}
222	vec += 2;
223	}
224	return 0;
225	}
226
227	void queue_fix_sofar(struct queue_entry *q) {
228	long sofar;
229
230	/* Fake up SOFAR field for currently-playing tracks that don't have it filled
231	* in by the speaker process. XXX this horrible bodge should go away when we
232	* have a more general implementation of pausing as that field will always
233	* have to be right for the playing track. */
234	if((q->state == playing_started
235	\|\| q->state == playing_paused)
236	&& q->type & DISORDER_PLAYER_PAUSES
237	&& (q->type & DISORDER_PLAYER_TYPEMASK) != DISORDER_PLAYER_RAW) {
238	if(q->lastpaused) {
239	if(q->uptopause == -1) /* Don't know how far thru. */
240	sofar = -1;
241	else if(q->lastresumed) /* Has been paused and resumed. */
242	sofar = q->uptopause + time(0) - q->lastresumed;
243	else /* Currently paused. */
244	sofar = q->uptopause;
245	} else /* Never been paused. */
246	sofar = time(0) - q->played;
247	q->sofar = sofar;
248	}
249	}
250
251	char queue_marshall(const struct queue_entry q) {
252	unsigned n;
253	const char vec[sizeof fields / sizeof fields], *v;
254	char r, s;
255	size_t len = 1;
256
257	for(n = 0; n < sizeof fields / sizeof *fields; ++n)
258	if((v = fields[n].marshall(q, fields[n].offset))) {
259	vec[n] = quoteutf8(v);
260	len += strlen(vec[n]) + strlen(fields[n].name) + 2;
261	} else
262	vec[n] = 0;
263	s = r = xmalloc_noptr(len);
264	for(n = 0; n < sizeof fields / sizeof *fields; ++n)
265	if(vec[n]) {
266	*s++ = ' ';
267	s += strlen(strcpy(s, fields[n].name));
268	*s++ = ' ';
269	s += strlen(strcpy(s, vec[n]));
270	}
271	return r;
272	}
273
274	static void queue_read_error(const char *msg,
275	void *u) {
276	fatal(0, "error parsing queue %s: %s", (const char *)u, msg);
277	}
278
279	static void queue_do_read(struct queue_entry head, const char path) {
280	char *buffer;
281	FILE *fp;
282	struct queue_entry *q;
283
284	if(!(fp = fopen(path, "r"))) {
285	if(errno == ENOENT)
286	return; /* no queue */
287	fatal(errno, "error opening %s", path);
288	}
289	head->next = head->prev = head;
290	while(!inputline(path, fp, &buffer, '\n')) {
291	q = xmalloc(sizeof *q);
292	queue_unmarshall(q, buffer, queue_read_error, (void *)path);
293	if(head == &qhead
294	&& (!q->track
295	\|\| !q->when))
296	fatal(0, "incomplete queue entry in %s", path);
297	l_add(head->prev, q);
298	}
299	if(ferror(fp)) fatal(errno, "error reading %s", path);
300	fclose(fp);
301	}
302
303	void queue_read(void) {
304	queue_do_read(&qhead, config_get_file("queue"));
305	}
306
307	void recent_read(void) {
308	struct queue_entry *q;
309
310	queue_do_read(&phead, config_get_file("recent"));
311	/* reset pcount after loading */
312	pcount = 0;
313	q = phead.next;
314	while(q != &phead) {
315	++pcount;
316	q = q->next;
317	}
318	}
319
320	static void queue_do_write(const struct queue_entry head, const char path) {
321	char *tmp;
322	FILE *fp;
323	struct queue_entry *q;
324
325	byte_xasprintf(&tmp, "%s.new", path);
326	if(!(fp = fopen(tmp, "w"))) fatal(errno, "error opening %s", tmp);
327	for(q = head->next; q != head; q = q->next)
328	if(fprintf(fp, "%s\n", queue_marshall(q)) < 0)
329	fatal(errno, "error writing %s", tmp);
330	if(fclose(fp) < 0) fatal(errno, "error closing %s", tmp);
331	if(rename(tmp, path) < 0) fatal(errno, "error replacing %s", path);
332	}
333
334	void queue_write(void) {
335	queue_do_write(&qhead, config_get_file("queue"));
336	}
337
338	void recent_write(void) {
339	queue_do_write(&phead, config_get_file("recent"));
340	}
341
342	void queue_id(struct queue_entry *q) {
343	static unsigned long serial;
344	unsigned long a[3];
345	char buffer[128];
346
347	a[0] = serial++ & 0xFFFFFFFFUL;
348	a[1] = time(0) & 0xFFFFFFFFUL;
349	a[2] = getpid() & 0xFFFFFFFFUL;
350	basen(a, 3, buffer, sizeof buffer, 62);
351	q->id = xstrdup(buffer);
352	}
353
354	struct queue_entry queue_add(const char track, const char *submitter,
355	int where) {
459d4402	356	struct queue_entry q, beforeme;
460b9539	357
	358	q = xmalloc(sizeof *q);
	359	q->track = xstrdup(track);
	360	q->submitter = submitter ? xstrdup(submitter) : 0;
	361	q->state = playing_unplayed;
	362	queue_id(q);
	363	time(&q->when);
	364	switch(where) {
	365	case WHERE_START:
	366	l_add(&qhead, q);
	367	break;
	368	case WHERE_END:
	369	l_add(qhead.prev, q);
	370	break;
	371	case WHERE_BEFORE_RANDOM:
459d4402	372	/* We want to find the point in the queue before the block of random tracks
	373	* at the end. */
	374	beforeme = &qhead;
	375	while(beforeme->prev != &qhead
	376	&& beforeme->prev->state == playing_random)
	377	beforeme = beforeme->prev;
	378	l_add(beforeme->prev, q);
460b9539	379	break;
	380	}
	381	/* submitter will be a null pointer for a scratch */
	382	if(submitter)
	383	notify_queue(track, submitter);
	384	eventlog_raw("queue", queue_marshall(q), (const char *)0);
	385	return q;
	386	}
	387
	388	int queue_move(struct queue_entry q, int delta, const char who) {
	389	int moved = 0;
	390	char buffer[20];
	391
	392	/* not the most efficient approach but hopefuly relatively comprehensible:
	393	* the idea is that for each step we determine which nodes are affected, and
	394	* fill in all the links starting at the 'prev' end and moving towards the
	395	* 'next' end. */
	396
	397	while(delta > 0 && q->prev != &qhead) {
	398	struct queue_entry n, p, *pp;
	399
	400	n = q->next;
	401	p = q->prev;
	402	pp = p->prev;
	403	pp->next = q;
	404	q->prev = pp;
	405	q->next = p;
	406	p->prev = q;
	407	p->next = n;
	408	n->prev = p;
	409	--delta;
	410	++moved;
	411	}
	412
	413	while(delta < 0 && q->next != &qhead) {
	414	struct queue_entry n, p, *nn;
	415
	416	p = q->prev;
	417	n = q->next;
	418	nn = n->next;
	419	p->next = n;
	420	n->prev = p;
	421	n->next = q;
	422	q->prev = n;
	423	q->next = nn;
	424	nn->prev = q;
	425	++delta;
	426	--moved;
	427	}
	428
	429	if(moved) {
	430	info("user %s moved %s", who, q->id);
	431	notify_queue_move(q->track, who);
	432	sprintf(buffer, "%d", moved);
	433	eventlog("moved", who, (char *)0);
	434	}
	435
	436	return delta;
	437	}
	438
	439	static int find_in_list(struct queue_entry *needle,
	440	int nqs, struct queue_entry **qs) {
	441	int n;
	442
443	for(n = 0; n < nqs; ++n)
444	if(qs[n] == needle)
445	return 1;
446	return 0;
447	}
448
449	void queue_moveafter(struct queue_entry *target,
450	int nqs, struct queue_entry **qs,
451	const char *who) {
452	struct queue_entry *q;
453	int n;
454
455	/* Normalize */
456	if(!target)
457	target = &qhead;
458	else
459	while(find_in_list(target, nqs, qs))
460	target = target->prev;
461	/* Do the move */
462	for(n = 0; n < nqs; ++n) {
463	q = qs[n];
464	l_remove(q);
465	l_add(target, q);
466	target = q;
467	/* Log the individual tracks */
468	info("user %s moved %s", who, q->id);
469	notify_queue_move(q->track, who);
470	}
471	/* Report that the queue changed to the event log */
472	eventlog("moved", who, (char *)0);
473	}
474
475	void queue_remove(struct queue_entry which, const char who) {
476	if(who) {
477	info("user %s removed %s", who, which->id);
478	notify_queue_move(which->track, who);
479	}
480	eventlog("removed", which->id, who, (const char *)0);
481	l_remove(which);
482	}
483
484	struct queue_entry queue_find(const char key) {
485	struct queue_entry *q;
486
487	for(q = qhead.next;
488	q != &qhead && strcmp(q->track, key) && strcmp(q->id, key);
489	q = q->next)
490	;
491	return q != &qhead ? q : 0;
492	}
493
494	void queue_played(struct queue_entry *q) {
495	while(pcount && pcount >= config->history) {
496	eventlog("recent_removed", phead.next->id, (char *)0);
497	l_remove(phead.next);
498	pcount--;
499	}
500	if(config->history) {
501	eventlog_raw("recent_added", queue_marshall(q), (char *)0);
502	l_add(phead.prev, q);
503	++pcount;
504	}
505	}
506
507	/*
508	Local Variables:
509	c-basic-offset:2
510	comment-column:40
511	fill-column:79
512	End:
513	*/