source: util.c @ b8a3e00

release-1.10release-1.8release-1.9
Last change on this file since b8a3e00 was b8a3e00, checked in by David Benjamin <davidben@mit.edu>, 13 years ago
Consistently use BarnOwl or barnowl BarnOwl refers to the program, barnowl is the executable and any other identifiers that are conventionally lowercase.
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File size: 20.5 KB
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1#include "owl.h"
2#include <stdlib.h>
3#include <string.h>
4#include <unistd.h>
5#include <ctype.h>
6#include <pwd.h>
7#include <sys/stat.h>
8#include <sys/types.h>
9#include <assert.h>
10#include <stdarg.h>
11#include <glib.h>
12#include <glib/gstdio.h>
13#include <glib-object.h>
14
15const char *skiptokens(const char *buff, int n) {
16  /* skips n tokens and returns where that would be. */
17  char quote = 0;
18  while (*buff && n>0) {
19      while (*buff == ' ') buff++;
20      while (*buff && (quote || *buff != ' ')) {
21        if(quote) {
22          if(*buff == quote) quote = 0;
23        } else if(*buff == '"' || *buff == '\'') {
24          quote = *buff;
25        }
26        buff++;
27      }
28      while (*buff == ' ') buff++;
29      n--;
30  }
31  return buff;
32}
33
34/* Return a "nice" version of the path.  Tilde expansion is done, and
35 * duplicate slashes are removed.  Caller must free the return.
36 */
37CALLER_OWN char *owl_util_makepath(const char *in)
38{
39  int i, j, x;
40  char *out, user[MAXPATHLEN];
41  struct passwd *pw;
42
43  out=g_new(char, MAXPATHLEN+1);
44  out[0]='\0';
45  j=strlen(in);
46  x=0;
47  for (i=0; i<j; i++) {
48    if (in[i]=='~') {
49      if ( (i==(j-1)) ||          /* last character */
50           (in[i+1]=='/') ) {     /* ~/ */
51        /* use my homedir */
52        pw=getpwuid(getuid());
53        if (!pw) {
54          out[x]=in[i];
55        } else {
56          out[x]='\0';
57          strcat(out, pw->pw_dir);
58          x+=strlen(pw->pw_dir);
59        }
60      } else {
61        /* another user homedir */
62        int a, b;
63        b=0;
64        for (a=i+1; i<j; a++) {
65          if (in[a]==' ' || in[a]=='/') {
66            break;
67          } else {
68            user[b]=in[a];
69            i++;
70            b++;
71          }
72        }
73        user[b]='\0';
74        pw=getpwnam(user);
75        if (!pw) {
76          out[x]=in[i];
77        } else {
78          out[x]='\0';
79          strcat(out, pw->pw_dir);
80          x+=strlen(pw->pw_dir);
81        }
82      }
83    } else if (in[i]=='/') {
84      /* check for a double / */
85      if (i<(j-1) && (in[i+1]=='/')) {
86        /* do nothing */
87      } else {
88        out[x]=in[i];
89        x++;
90      }
91    } else {
92      out[x]=in[i];
93      x++;
94    }
95  }
96  out[x]='\0';
97  return(out);
98}
99
100void owl_ptr_array_free(GPtrArray *array, GDestroyNotify element_free_func)
101{
102  /* TODO: when we move to requiring glib 2.22+, use
103   * g_ptr_array_new_with_free_func instead. */
104  if (element_free_func)
105    g_ptr_array_foreach(array, (GFunc)element_free_func, NULL);
106  g_ptr_array_free(array, true);
107}
108
109/* Break a command line up into argv, argc.  The caller must free
110   the returned values with g_strfreev.  If there is an error argc will be set
111   to -1, argv will be NULL and the caller does not need to free anything. The
112   returned vector is NULL-terminated. */
113CALLER_OWN char **owl_parseline(const char *line, int *argc)
114{
115  GPtrArray *argv;
116  int i, len, between=1;
117  GString *curarg;
118  char quote;
119
120  argv = g_ptr_array_new();
121  len=strlen(line);
122  curarg = g_string_new("");
123  quote='\0';
124  if (argc) *argc=0;
125  for (i=0; i<len+1; i++) {
126    /* find the first real character */
127    if (between) {
128      if (line[i]==' ' || line[i]=='\t' || line[i]=='\0') {
129        continue;
130      } else {
131        between=0;
132        i--;
133        continue;
134      }
135    }
136
137    /* deal with a quote character */
138    if (line[i]=='"' || line[i]=="'"[0]) {
139      /* if this type of quote is open, close it */
140      if (quote==line[i]) {
141        quote='\0';
142        continue;
143      }
144
145      /* if no quoting is open then open with this */
146      if (quote=='\0') {
147        quote=line[i];
148        continue;
149      }
150
151      /* if another type of quote is open then treat this as a literal */
152      g_string_append_c(curarg, line[i]);
153      continue;
154    }
155
156    /* if it's not a space or end of command, then use it */
157    if (line[i]!=' ' && line[i]!='\t' && line[i]!='\n' && line[i]!='\0') {
158      g_string_append_c(curarg, line[i]);
159      continue;
160    }
161
162    /* otherwise, if we're not in quotes, add the whole argument */
163    if (quote=='\0') {
164      /* add the argument */
165      g_ptr_array_add(argv, g_string_free(curarg, false));
166      curarg = g_string_new("");
167      between=1;
168      continue;
169    }
170
171    /* if it is a space and we're in quotes, then use it */
172    g_string_append_c(curarg, line[i]);
173  }
174
175  if (argc) *argc = argv->len;
176  g_ptr_array_add(argv, NULL);
177  g_string_free(curarg, true);
178
179  /* check for unbalanced quotes */
180  if (quote!='\0') {
181    owl_ptr_array_free(argv, g_free);
182    if (argc) *argc = -1;
183    return(NULL);
184  }
185
186  return (char**)g_ptr_array_free(argv, false);
187}
188
189/* Appends a quoted version of arg suitable for placing in a
190 * command-line to a GString. Does not append a space. */
191void owl_string_append_quoted_arg(GString *buf, const char *arg)
192{
193  const char *argp;
194  if (arg[0] == '\0') {
195    /* Quote the empty string. */
196    g_string_append(buf, "''");
197  } else if (arg[strcspn(arg, "'\" \n\t")] == '\0') {
198    /* If there are no nasty characters, return as-is. */
199    g_string_append(buf, arg);
200  } else if (!strchr(arg, '\'')) {
201    /* Single-quote if possible. */
202    g_string_append_c(buf, '\'');
203    g_string_append(buf, arg);
204    g_string_append_c(buf, '\'');
205  } else {
206    /* Nasty case: double-quote, but change all internal "s to "'"'"
207     * so that they are single-quoted because we're too cool for
208     * backslashes.
209     */
210    g_string_append_c(buf, '"');
211    for (argp = arg; *argp; argp++) {
212      if (*argp == '"')
213        g_string_append(buf, "\"'\"'\"");
214      else
215        g_string_append_c(buf, *argp);
216    }
217    g_string_append_c(buf, '"');
218  }
219}
220
221/*
222 * Appends 'tmpl' to 'buf', replacing any instances of '%q' with arguments from
223 * the varargs provided, quoting them to be safe for placing in a BarnOwl
224 * command line.
225 */
226void owl_string_appendf_quoted(GString *buf, const char *tmpl, ...)
227{
228  va_list ap;
229  va_start(ap, tmpl);
230  owl_string_vappendf_quoted(buf, tmpl, ap);
231  va_end(ap);
232}
233
234void owl_string_vappendf_quoted(GString *buf, const char *tmpl, va_list ap)
235{
236  const char *p = tmpl, *last = tmpl;
237  while (true) {
238    p = strchr(p, '%');
239    if (p == NULL) break;
240    if (*(p+1) != 'q') {
241      p++;
242      if (*p) p++;
243      continue;
244    }
245    g_string_append_len(buf, last, p - last);
246    owl_string_append_quoted_arg(buf, va_arg(ap, char *));
247    p += 2; last = p;
248  }
249
250  g_string_append(buf, last);
251}
252
253CALLER_OWN char *owl_string_build_quoted(const char *tmpl, ...)
254{
255  GString *buf = g_string_new("");
256  va_list ap;
257  va_start(ap, tmpl);
258  owl_string_vappendf_quoted(buf, tmpl, ap);
259  va_end(ap);
260  return g_string_free(buf, false); 
261}
262
263/* Returns a quoted version of arg suitable for placing in a
264 * command-line. Result should be freed with g_free. */
265CALLER_OWN char *owl_arg_quote(const char *arg)
266{
267  GString *buf = g_string_new("");;
268  owl_string_append_quoted_arg(buf, arg);
269  return g_string_free(buf, false);
270}
271
272/* caller must free the return */
273CALLER_OWN char *owl_util_minutes_to_timestr(int in)
274{
275  int days, hours;
276  long run;
277  char *out;
278
279  run=in;
280
281  days=run/1440;
282  run-=days*1440;
283  hours=run/60;
284  run-=hours*60;
285
286  if (days>0) {
287    out=g_strdup_printf("%i d %2.2i:%2.2li", days, hours, run);
288  } else {
289    out=g_strdup_printf("    %2.2i:%2.2li", hours, run);
290  }
291  return(out);
292}
293
294/* These are in order of their value in owl.h */
295static const struct {
296  int number;
297  const char *name;
298} color_map[] = {
299  {OWL_COLOR_INVALID, "invalid"},
300  {OWL_COLOR_DEFAULT, "default"},
301  {OWL_COLOR_BLACK, "black"},
302  {OWL_COLOR_RED, "red"},
303  {OWL_COLOR_GREEN, "green"},
304  {OWL_COLOR_YELLOW,"yellow"},
305  {OWL_COLOR_BLUE, "blue"},
306  {OWL_COLOR_MAGENTA, "magenta"},
307  {OWL_COLOR_CYAN, "cyan"},
308  {OWL_COLOR_WHITE, "white"},
309};
310
311/* Return the owl color associated with the named color.  Return -1
312 * if the named color is not available
313 */
314int owl_util_string_to_color(const char *color)
315{
316  int c, i;
317  char *p;
318
319  for (i = 0; i < (sizeof(color_map)/sizeof(color_map[0])); i++)
320    if (strcasecmp(color, color_map[i].name) == 0)
321      return color_map[i].number;
322
323  c = strtol(color, &p, 10);
324  if (p != color && c >= -1 && c < COLORS) {
325    return(c);
326  }
327  return(OWL_COLOR_INVALID);
328}
329
330/* Return a string name of the given owl color */
331const char *owl_util_color_to_string(int color)
332{
333  if (color >= OWL_COLOR_INVALID && color <= OWL_COLOR_WHITE)
334    return color_map[color - OWL_COLOR_INVALID].name;
335  return("Unknown color");
336}
337
338/* Get the default tty name.  Caller must free the return */
339CALLER_OWN char *owl_util_get_default_tty(void)
340{
341  const char *tmp;
342  char *out;
343
344  if (getenv("DISPLAY")) {
345    out=g_strdup(getenv("DISPLAY"));
346  } else if ((tmp=ttyname(fileno(stdout)))!=NULL) {
347    out=g_strdup(tmp);
348    if (!strncmp(out, "/dev/", 5)) {
349      g_free(out);
350      out=g_strdup(tmp+5);
351    }
352  } else {
353    out=g_strdup("unknown");
354  }
355  return(out);
356}
357
358/* strip leading and trailing new lines.  Caller must free the
359 * return.
360 */
361CALLER_OWN char *owl_util_stripnewlines(const char *in)
362{
363 
364  char  *tmp, *ptr1, *ptr2, *out;
365
366  ptr1=tmp=g_strdup(in);
367  while (ptr1[0]=='\n') {
368    ptr1++;
369  }
370  ptr2=ptr1+strlen(ptr1)-1;
371  while (ptr2>ptr1 && ptr2[0]=='\n') {
372    ptr2[0]='\0';
373    ptr2--;
374  }
375
376  out=g_strdup(ptr1);
377  g_free(tmp);
378  return(out);
379}
380
381
382/* If filename is a link, recursively resolve symlinks.  Otherwise, return the filename
383 * unchanged.  On error, call owl_function_error and return NULL.
384 *
385 * This function assumes that filename eventually resolves to an acutal file.
386 * If you want to check this, you should stat() the file first.
387 *
388 * The caller of this function is responsible for freeing the return value.
389 *
390 * Error conditions are the same as g_file_read_link.
391 */
392CALLER_OWN gchar *owl_util_recursive_resolve_link(const char *filename)
393{
394  gchar *last_path = g_strdup(filename);
395  GError *err = NULL;
396
397  while (g_file_test(last_path, G_FILE_TEST_IS_SYMLINK)) {
398    gchar *link_path = g_file_read_link(last_path, &err);
399    if (link_path == NULL) {
400      owl_function_error("Cannot resolve symlink %s: %s",
401                         last_path, err->message);
402      g_error_free(err);
403      g_free(last_path);
404      return NULL;
405    }
406
407    /* Deal with obnoxious relative paths. If we really care, all this
408     * is racy. Whatever. */
409    if (!g_path_is_absolute(link_path)) {
410      char *last_dir = g_path_get_dirname(last_path);
411      char *tmp = g_build_path(G_DIR_SEPARATOR_S,
412                               last_dir,
413                               link_path,
414                               NULL);
415      g_free(last_dir);
416      g_free(link_path);
417      link_path = tmp;
418    }
419
420    g_free(last_path);
421    last_path = link_path;
422  }
423  return last_path;
424}
425
426/* Delete all lines matching "line" from the named file.  If no such
427 * line is found the file is left intact.  If backup==1 then leave a
428 * backup file containing the original contents.  The match is
429 * case-insensitive.
430 *
431 * Returns the number of lines removed on success.  Returns -1 on failure.
432 */
433int owl_util_file_deleteline(const char *filename, const char *line, int backup)
434{
435  char *backupfile, *newfile, *buf = NULL;
436  gchar *actual_filename; /* gchar; we need to g_free it */
437  FILE *old, *new;
438  struct stat st;
439  int numremoved = 0;
440
441  if ((old = fopen(filename, "r")) == NULL) {
442    owl_function_error("Cannot open %s (for reading): %s",
443                       filename, strerror(errno));
444    return -1;
445  }
446
447  if (fstat(fileno(old), &st) != 0) {
448    owl_function_error("Cannot stat %s: %s", filename, strerror(errno));
449    return -1;
450  }
451
452  /* resolve symlinks, because link() fails on symlinks, at least on AFS */
453  actual_filename = owl_util_recursive_resolve_link(filename);
454  if (actual_filename == NULL)
455    return -1; /* resolving the symlink failed, but we already logged this error */
456
457  newfile = g_strdup_printf("%s.new", actual_filename);
458  if ((new = fopen(newfile, "w")) == NULL) {
459    owl_function_error("Cannot open %s (for writing): %s",
460                       actual_filename, strerror(errno));
461    g_free(newfile);
462    fclose(old);
463    g_free(actual_filename);
464    return -1;
465  }
466
467  if (fchmod(fileno(new), st.st_mode & 0777) != 0) {
468    owl_function_error("Cannot set permissions on %s: %s",
469                       actual_filename, strerror(errno));
470    unlink(newfile);
471    fclose(new);
472    g_free(newfile);
473    fclose(old);
474    g_free(actual_filename);
475    return -1;
476  }
477
478  while (owl_getline_chomp(&buf, old))
479    if (strcasecmp(buf, line) != 0)
480      fprintf(new, "%s\n", buf);
481    else
482      numremoved++;
483  g_free(buf);
484
485  fclose(new);
486  fclose(old);
487
488  if (backup) {
489    backupfile = g_strdup_printf("%s.backup", actual_filename);
490    unlink(backupfile);
491    if (link(actual_filename, backupfile) != 0) {
492      owl_function_error("Cannot link %s: %s", backupfile, strerror(errno));
493      g_free(backupfile);
494      unlink(newfile);
495      g_free(newfile);
496      return -1;
497    }
498    g_free(backupfile);
499  }
500
501  if (rename(newfile, actual_filename) != 0) {
502    owl_function_error("Cannot move %s to %s: %s",
503                       newfile, actual_filename, strerror(errno));
504    numremoved = -1;
505  }
506
507  unlink(newfile);
508  g_free(newfile);
509
510  g_free(actual_filename);
511
512  return numremoved;
513}
514
515/* Return the base class or instance from a zephyr class, by removing
516   leading `un' or trailing `.d'.
517   The caller is responsible for freeing the allocated string.
518*/
519CALLER_OWN char *owl_util_baseclass(const char *class)
520{
521  char *start, *end;
522
523  while(!strncmp(class, "un", 2)) {
524    class += 2;
525  }
526
527  start = g_strdup(class);
528  end = start + strlen(start) - 1;
529  while(end > start && *end == 'd' && *(end-1) == '.') {
530    end -= 2;
531  }
532  *(end + 1) = 0;
533
534  return start;
535}
536
537const char * owl_get_datadir(void)
538{
539  const char * datadir = getenv("BARNOWL_DATA_DIR");
540  if(datadir != NULL)
541    return datadir;
542  return DATADIR;
543}
544
545const char * owl_get_bindir(void)
546{
547  const char * bindir = getenv("BARNOWL_BIN_DIR");
548  if(bindir != NULL)
549    return bindir;
550  return BINDIR;
551}
552
553/* Strips format characters from a valid utf-8 string. Returns the
554   empty string if 'in' does not validate.  Caller must free the return. */
555CALLER_OWN char *owl_strip_format_chars(const char *in)
556{
557  char *r;
558  if (g_utf8_validate(in, -1, NULL)) {
559    const char *s, *p;
560    r = g_new(char, strlen(in)+1);
561    r[0] = '\0';
562    s = in;
563    p = strchr(s, OWL_FMTEXT_UC_STARTBYTE_UTF8);
564    while(p) {
565      /* If it's a format character, copy up to it, and skip all
566         immediately following format characters. */
567      if (owl_fmtext_is_format_char(g_utf8_get_char(p))) {
568        strncat(r, s, p-s);
569        p = g_utf8_next_char(p);
570        while (owl_fmtext_is_format_char(g_utf8_get_char(p))) {
571          p = g_utf8_next_char(p);
572        }
573        s = p;
574        p = strchr(s, OWL_FMTEXT_UC_STARTBYTE_UTF8);
575      }
576      else {
577        p = strchr(p+1, OWL_FMTEXT_UC_STARTBYTE_UTF8);
578      }
579    }
580    if (s) strcat(r,s);
581  }
582  else {
583    r = g_strdup("");
584  }
585  return r;
586}
587
588/* If in is not UTF-8, convert from ISO-8859-1. We may want to allow
589 * the caller to specify an alternative in the future. We also strip
590 * out characters in Unicode Plane 16, as we use that plane internally
591 * for formatting.
592 * Caller must free the return.
593 */
594CALLER_OWN char *owl_validate_or_convert(const char *in)
595{
596  if (g_utf8_validate(in, -1, NULL)) {
597    return owl_strip_format_chars(in);
598  }
599  else {
600    return g_convert(in, -1,
601                     "UTF-8", "ISO-8859-1",
602                     NULL, NULL, NULL);
603  }
604}
605/*
606 * Validate 'in' as UTF-8, and either return a copy of it, or an empty
607 * string if it is invalid utf-8.
608 * Caller must free the return.
609 */
610CALLER_OWN char *owl_validate_utf8(const char *in)
611{
612  char *out;
613  if (g_utf8_validate(in, -1, NULL)) {
614    out = g_strdup(in);
615  } else {
616    out = g_strdup("");
617  }
618  return out;
619}
620
621/* This is based on _extract() and _isCJ() from perl's Text::WrapI18N */
622int owl_util_can_break_after(gunichar c)
623{
624 
625  if (c == ' ') return 1;
626  if (c >= 0x3000 && c <= 0x312f) {
627    /* CJK punctuations, Hiragana, Katakana, Bopomofo */
628    if (c == 0x300a || c == 0x300c || c == 0x300e ||
629        c == 0x3010 || c == 0x3014 || c == 0x3016 ||
630        c == 0x3018 || c == 0x301a)
631      return 0;
632    return 1;
633  }
634  if (c >= 0x31a0 && c <= 0x31bf) {return 1;}  /* Bopomofo */
635  if (c >= 0x31f0 && c <= 0x31ff) {return 1;}  /* Katakana extension */
636  if (c >= 0x3400 && c <= 0x9fff) {return 1;}  /* Han Ideogram */
637  if (c >= 0xf900 && c <= 0xfaff) {return 1;}  /* Han Ideogram */
638  if (c >= 0x20000 && c <= 0x2ffff) {return 1;}  /* Han Ideogram */
639  return 0;
640}
641
642/* caller must free the return */
643CALLER_OWN char *owl_escape_highbit(const char *str)
644{
645  GString *out = g_string_new("");
646  unsigned char c;
647  while((c = (*str++))) {
648    if(c == '\\') {
649      g_string_append(out, "\\\\");
650    } else if(c & 0x80) {
651      g_string_append_printf(out, "\\x%02x", (int)c);
652    } else {
653      g_string_append_c(out, c);
654    }
655  }
656  return g_string_free(out, 0);
657}
658
659/* innards of owl_getline{,_chomp} below */
660static int owl_getline_internal(char **s, FILE *fp, int newline)
661{
662  int size = 0;
663  int target = 0;
664  int count = 0;
665  int c;
666
667  while (1) {
668    c = getc(fp);
669    if ((target + 1) > size) {
670      size += BUFSIZ;
671      *s = g_renew(char, *s, size);
672    }
673    if (c == EOF)
674      break;
675    count++;
676    if (c != '\n' || newline)
677        (*s)[target++] = c;
678    if (c == '\n')
679      break;
680  }
681  (*s)[target] = 0;
682
683  return count;
684}
685
686/* Read a line from fp, allocating memory to hold it, returning the number of
687 * byte read.  *s should either be NULL or a pointer to memory allocated with
688 * g_malloc; it will be g_renew'd as appropriate.  The caller must
689 * eventually free it.  (This is roughly the interface of getline in the gnu
690 * libc).
691 *
692 * The final newline will be included if it's there.
693 */
694int owl_getline(char **s, FILE *fp)
695{
696  return owl_getline_internal(s, fp, 1);
697}
698
699/* As above, but omitting the final newline */
700int owl_getline_chomp(char **s, FILE *fp)
701{
702  return owl_getline_internal(s, fp, 0);
703}
704
705/* Read the rest of the input available in fp into a string. */
706CALLER_OWN char *owl_slurp(FILE *fp)
707{
708  char *buf = NULL;
709  char *p;
710  int size = 0;
711  int count;
712
713  while (1) {
714    buf = g_renew(char, buf, size + BUFSIZ);
715    p = &buf[size];
716    size += BUFSIZ;
717
718    if ((count = fread(p, 1, BUFSIZ, fp)) < BUFSIZ)
719      break;
720  }
721  p[count] = 0;
722
723  return buf;
724}
725
726int owl_util_get_colorpairs(void) {
727#ifndef NCURSES_EXT_COLORS
728  /* Without ext-color support (an ABI change), ncurses only supports 256
729   * different color pairs. However, it gives us a larger number even if your
730   * ncurses is compiled without ext-color. */
731  return MIN(COLOR_PAIRS, 256);
732#else
733  return COLOR_PAIRS;
734#endif
735}
736
737gulong owl_dirty_window_on_signal(owl_window *w, gpointer sender, const gchar *detailed_signal)
738{
739  return owl_signal_connect_object(sender, detailed_signal, G_CALLBACK(owl_window_dirty), w, G_CONNECT_SWAPPED);
740}
741
742typedef struct { /*noproto*/
743  GObject  *sender;
744  gulong    signal_id;
745} SignalData;
746
747static void _closure_invalidated(gpointer data, GClosure *closure);
748
749/*
750 * GObject's g_signal_connect_object has a documented bug. This function is
751 * identical except it does not leak the signal handler.
752 */
753gulong owl_signal_connect_object(gpointer sender, const gchar *detailed_signal, GCallback c_handler, gpointer receiver, GConnectFlags connect_flags)
754{
755  g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (sender), 0);
756  g_return_val_if_fail (detailed_signal != NULL, 0);
757  g_return_val_if_fail (c_handler != NULL, 0);
758
759  if (receiver) {
760    SignalData *sdata;
761    GClosure *closure;
762    gulong signal_id;
763
764    g_return_val_if_fail (G_IS_OBJECT (receiver), 0);
765
766    closure = ((connect_flags & G_CONNECT_SWAPPED) ? g_cclosure_new_object_swap : g_cclosure_new_object) (c_handler, receiver);
767    signal_id = g_signal_connect_closure (sender, detailed_signal, closure, connect_flags & G_CONNECT_AFTER);
768
769    /* Register the missing hooks */
770    sdata = g_slice_new0(SignalData);
771    sdata->sender = sender;
772    sdata->signal_id = signal_id;
773
774    g_closure_add_invalidate_notifier(closure, sdata, _closure_invalidated);
775
776    return signal_id;
777  } else {
778    return g_signal_connect_data(sender, detailed_signal, c_handler, NULL, NULL, connect_flags);
779  }
780}
781
782/*
783 * There are three ways the signal could come to an end:
784 *
785 * 1. The user explicitly disconnects it with the returned signal_id.
786 *    - In that case, the disconnection unref's the closure, causing it
787 *      to first be invalidated. The handler's already disconnected, so
788 *      we have no work to do.
789 * 2. The sender gets destroyed.
790 *    - GObject will disconnect each signal which then goes into the above
791 *      case. Our handler does no work.
792 * 3. The receiver gets destroyed.
793 *    - The GClosure was created by g_cclosure_new_object_{,swap} which gets
794 *      invalidated when the receiver is destroyed. We then follow through case 1
795 *      again, but *this* time, the handler has not been disconnected. We then
796 *      clean up ourselves.
797 *
798 * We can't actually hook into this process earlier with weakrefs as GObject
799 * will, on object dispose, first disconnect signals, then invalidate closures,
800 * and notify weakrefs last.
801 */
802static void _closure_invalidated(gpointer data, GClosure *closure)
803{
804  SignalData *sdata = data;
805  if (g_signal_handler_is_connected(sdata->sender, sdata->signal_id)) {
806    g_signal_handler_disconnect(sdata->sender, sdata->signal_id);
807  }
808  g_slice_free(SignalData, sdata);
809}
810
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