pidgin/pidgin

Fix the infinite resizing freeze
release-2.x.y
2022-04-15, Belgin Știrbu
0079467afee4
Fix the infinite resizing freeze

This appears related to libpango somehow, as in Debian
Bullseye, libpango splits URLs with dashes at the end,
but in Debian Bookworm, the URLs are not split with dashes
at the end, and the bug does not appear to be triggered
in Bookworm.

This patch makes the assumption that the gtkimhtml widgets
stored in a PidginConversation normally resize in an
alternating manner. However, when the bug is triggered,
only the "entry" gtkimhtml member of PidginConversation
resizes, so we allow "entry" to resize only up to 3 times
in a row.

Testing Done:
Compiled and tested on several desktop environments on a few
GNU/Linux distros by pasting the link mentioned
here https://issues.imfreedom.org/issue/PIDGIN-17413 moving
the cursor at the beginning of the buffer, and holding
the spacebar pressed.

Bugs closed: PIDGIN-16753, PIDGIN-16999, PIDGIN-17287, PIDGIN-17413, PIDGIN-17430, PIDGIN-17568, PIDGIN-17602

Reviewed at https://reviews.imfreedom.org/r/1342/
/**
* @file stringref.c Reference-counted immutable strings
* @ingroup core
*/
/* purple
*
* Purple is the legal property of its developers, whose names are too numerous
* to list here. Please refer to the COPYRIGHT file distributed with this
* source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA
*
*/
#include "internal.h"
#include <string.h>
#include <stdarg.h>
#include "debug.h"
#include "eventloop.h"
#include "stringref.h"
/**
* The internal representation of a stringref.
*
* @note For this structure to be useful, the string contained within
* it must be immutable -- for this reason, do _not_ access it
* directly!
*/
struct _PurpleStringref {
guint32 ref; /**< The reference count of this string.
* Note that reference counts are only
* 31 bits, and the high-order bit
* indicates whether this string is up
* for GC at the next idle handler...
* But you aren't going to touch this
* anyway, right? */
char value[1]; /**< The string contained in this ref.
* Notice that it is simply "hanging
* off the end" of the ref ... this
* is to save an allocation. */
};
#define REFCOUNT(x) ((x) & 0x7fffffff)
static GList *gclist = NULL;
static void stringref_free(PurpleStringref *stringref);
static gboolean gs_idle_cb(gpointer data);
PurpleStringref *purple_stringref_new(const char *value)
{
PurpleStringref *newref;
size_t len;
if (value == NULL)
return NULL;
len = strlen(value);
newref = g_malloc(sizeof(PurpleStringref) + len);
/* g_strlcpy() takes the size of the buffer, including the NUL.
strlen() returns the length of the string, without the NUL. */
g_strlcpy(newref->value, value, len + 1);
newref->ref = 1;
return newref;
}
PurpleStringref *purple_stringref_new_noref(const char *value)
{
PurpleStringref *newref;
if (value == NULL)
return NULL;
newref = g_malloc(sizeof(PurpleStringref) + strlen(value));
strcpy(newref->value, value);
newref->ref = 0x80000000;
if (gclist == NULL)
purple_timeout_add(0, gs_idle_cb, NULL);
gclist = g_list_prepend(gclist, newref);
return newref;
}
PurpleStringref *purple_stringref_printf(const char *format, ...)
{
PurpleStringref *newref;
va_list ap;
if (format == NULL)
return NULL;
va_start(ap, format);
newref = g_malloc(sizeof(PurpleStringref) + g_printf_string_upper_bound(format, ap));
vsprintf(newref->value, format, ap);
va_end(ap);
newref->ref = 1;
return newref;
}
PurpleStringref *purple_stringref_ref(PurpleStringref *stringref)
{
if (stringref == NULL)
return NULL;
stringref->ref++;
return stringref;
}
void purple_stringref_unref(PurpleStringref *stringref)
{
if (stringref == NULL)
return;
if (REFCOUNT(--(stringref->ref)) == 0) {
if (stringref->ref & 0x80000000)
gclist = g_list_remove(gclist, stringref);
stringref_free(stringref);
}
}
const char *purple_stringref_value(const PurpleStringref *stringref)
{
return (stringref == NULL ? NULL : stringref->value);
}
int purple_stringref_cmp(const PurpleStringref *s1, const PurpleStringref *s2)
{
return (s1 == s2 ? 0 : strcmp(purple_stringref_value(s1), purple_stringref_value(s2)));
}
size_t purple_stringref_len(const PurpleStringref *stringref)
{
return strlen(purple_stringref_value(stringref));
}
static void stringref_free(PurpleStringref *stringref)
{
#ifdef DEBUG
if (REFCOUNT(stringref->ref) != 0) {
purple_debug(PURPLE_DEBUG_ERROR, "stringref", "Free of nonzero (%d) ref stringref!\n", REFCOUNT(stringref->ref));
return;
}
#endif /* DEBUG */
g_free(stringref);
}
static gboolean gs_idle_cb(gpointer data)
{
PurpleStringref *ref;
GList *del;
while (gclist != NULL) {
ref = gclist->data;
if (REFCOUNT(ref->ref) == 0) {
stringref_free(ref);
}
del = gclist;
gclist = gclist->next;
g_list_free_1(del);
}
return FALSE;
}