Up until now, using NULL as key in av_dict_get() on a non-empty
AVDictionary would crash; using NULL as key in av_dict_set()
would also crash for a non-empty AVDictionary unless AV_DICT_MULTIKEY
was set; in case the dictionary was initially empty or AV_DICT_MULTIKEY
was set, it was even possible for av_dict_set() to succeed when
adding a NULL key, namely when one uses a value != NULL and
the AV_DICT_DONT_STRDUP_VAL flag. Using av_dict_get() on such
an AVDictionary will usually lead to crashes, though.
Fix this by actually checking for key in both functions; error out
if they are NULL.
While just at it, also stop relying on av_strdup(NULL) to return NULL
in av_dict_set().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
When appending two values (due to AV_DICT_APPEND), the earlier code
would first zero-allocate a buffer of the required size and then
copy both parts into it via av_strlcat(). This is problematic,
as it leads to quadratic performance in case of frequent enlargements.
Fix this by using av_realloc() (which is hopefully designed to handle
such cases in a better way than simply throwing the buffer we already
have away) and by copying the string via memcpy() (after all, we already
calculated the strlen of both strings).
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
If a key already exists in an AVDictionary and the AV_DICT_APPEND flag
is set, the old entry is at first discarded from the dictionary, but
a pointer to the value is kept. Lateron enough memory to store the
appended string is allocated; should this allocation fail, the old string
is not freed and hence leaks. This commit changes this by moving
creating the combined value to an earlier point in the function,
which also ensures that the AVDictionary is unchanged in case of errors.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
We know that an AVDictionary is not empty if we have just added
an entry to it, so only check for it being empty on the branch
that does not do so.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Deleting a non-existing item should not invalidate existing entries returned
with av_dict_get.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Marton Balint <cus@passwd.hu>
Unfortunately this was not explicitly documented and thus
might be risky.
But all uses I could find in FFmpeg and one in VLC had a memleak
in these cases, and I could not find any that relied on the previous
behaviour.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
This allows getting rid of the many, slightly differing, implementations
of basically the same thing.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
This avoids temporaries or ugly casting in the calling code where
const dictionaries are used. Esp. helpful when writing C++ wrappers
for an AVDictionary having const member functions and CTORs with const
references.
Signed-off-by: Roman Fietze <roman.fietze@telemotive.de>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
As far as I can tell the code should not change behaviour
depending on locale in any of these places.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Memory passed to av_realloc must come from malloc,
calloc or realloc, and not e.g. memalign. realloc(3):
The realloc() function changes the size of the memory block pointed to
by ptr to size bytes. (...) Unless ptr is NULL, it must have been
returned by an earlier call to malloc(), calloc() or realloc().
The issue has been found by debugallocation, a part of google-perftools:
http://code.google.com/p/gperftools/ .
This makes fate pass when using LD_PRELOAD-ed debugallocation.
See also earlier discussion
http://ffmpeg.org/pipermail/ffmpeg-devel/2013-January/137234.html
Signed-off-by: Paweł Hajdan, Jr <phajdan@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This adds a function to retrieve the number of entries in a
dictionary and updates the places directly accessing what should
be an opaque struct to use this new function instead.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Andreas Rheinhardt
Limin Wang
Marton Balint
Thilo Borgmann
Vittorio Giovara
Michael Niedermayer
Lukasz Marek
Luca Barbato
wm4
Reimar Döffinger
Janne Grunau
Diego Biurrun
Roman Fietze
Patrice Clement
Clément Bœsch
Paweł Hajdan, Jr
Justin Ruggles
Martin Storsjö
Mans Rullgard
Anton Khirnov