Add a mechanism to AVClass to allow objects to signal their state to
generic code. When an object flags itself with the 'initialized' state,
print an error (and fail, after the next major bump) if the caller
attempts to set non-runtime options.
The options-setting functions share several operations at their
beginnings - locating the option and the object to operate on, handling
the read-only and deprecated flags, and constructing the pointer to the
target value. Some of the functions also do not perform some of the
checks, although they should. E.g. a deprecation warning is currently
only printed for av_opt_set().
Introduce a prologue function that is called from every av_opt_set*()
and performs all these common initialization operations.
In one of the failure paths of av_opt_get_array, the ret variable
was accidentally declared again, shadowing the outer one and once when
jumping to the fail label would return the still uninitialised outer
one.
To fix this simply remove the local declaration of ret that shadowed
the outer one.
Introduced in d89930f866
Fixes: CID1618663 Uninitialized scalar variable
In one failure path for av_opt_set_array, the ret variable
was declared again, shadowing the outer one and writing the
return value to the wrong one and then after the goto returning
the uninitialized one instead.
Introduced in 450a3f58ed
Fixes: CID1619242 Uninitialized scalar variable
Previously one could only replace the entire array with a new one
deserialized from a string. The new API allows inserting, replacing, and
removing arbitrary element ranges.
There are lots of files that don't need it: The number of object
files that actually need it went down from 2011 to 884 here.
Keep it for external users in order to not cause breakages.
Also improve the other headers a bit while just at it.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
GCC 9-13 do not emit warnings for this at all optimization
levels even when -Wmaybe-uninitialized is not disabled.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
A pointer conversion is UB if the resulting pointer is not
correctly aligned for the resultant type, even if no
load/store is ever performed through that pointer (C11 6.3.2.3 (7)).
This may happen in opt_copy_elem(), because the pointers are
converted even when they belong to a type that does not guarantee
sufficient alignment.
Fix this by deferring the cast after having checked the type.
Also make the casts -Wcast-qual safe and avoid an indirection
for src.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is not documented to be safe and in any case it is nonsense:
Currently av_strdup(NULL) returns NULL and in order to distinguish
this from a genuine allocation failure, opt_copy_elem()
checked afterwards whether src was actually NULL. But then one
can simply check in advance whether one should call av_strdup()
at all.
set_string() was even worse and returned ENOMEM in case the value
to be duplicated is NULL; this only worked because
av_opt_set_defaults2() does not check the return value at all
(given that it can't propagate it).
These two places account for 389114 of 390356 av_strdup(NULL)
calls during one FATE run.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Replace the opt_size() function, currently only called from
av_opt_copy(), with
* a constant array of element sizes
* a function that signals whether an option type is POD (i.e.
memcpyable) or not
Will be useful in following commits.
av_get_sample/pix_fmt() return their respective enums
and are therefore not of the type int (*)(const char*),
yet they are called as-if they were of this type.
This works in practice, but is actually undefined behaviour.
With Clang 17 UBSan these violations are flagged, affecting lots
of tests. The number of failing tests went down from 3363 to 164
here with this patch.
Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It uses the int64_t instead of the double member.
(This code can currently not be reached: av_opt_get() calls
av_opt_find2() with NULL as unit in which case AV_OPT_TYPE_CONST
options are never returned, leading av_opt_get() to always
return AVERROR_OPTION_NOT_FOUND when searching for AV_OPT_TYPE_CONST*.
For the same reason the code read_number() will never be called
from get_number() when searching for an option of type
AV_OPT_TYPE_CONST. The other callers of read_number() also only
call it with types other than AV_OPT_TYPE_CONST.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
If the dictionary provided on input contains multiple entries for an
option (relevant for flags modifying the previous value with '+' or
'-') and the option is not found in the target object, only the last
entry would be returned to the caller.
Pass AV_DICT_MULTIKEY to av_dict_set() to make sure all such entries are
returned.
Before:
overlay AVOptions:
x <string> ..FV....... set the x expression (default "0")
y <string> ..FV....... set the y expression (default "0")
eof_action <int> ..FV....... Action to take when encountering EOF from secondary input (from 0 to 2) (default repeat)
repeat 0 ..FV....... Repeat the previous frame.
endall 1 ..FV....... End both streams.
pass 2 ..FV....... Pass through the main input.
eval <int> ..FV....... specify when to evaluate expressions (from 0 to 1) (default frame)
After:
a
overlay AVOptions:
x <string> ..FV....... set the x expression (default "0")
y <string> ..FV....... set the y expression (default "0")
eof_action <int> ..FV....... Action to take when encountering EOF from secondary input (from 0 to 2) (default repeat)
repeat 0 ..FV....... Repeat the previous frame.
endall 1 ..FV....... End both streams.
pass 2 ..FV....... Pass through the main input.
eval <int> ..FV....... specify when to evaluate expressions (from 0 to 1) (default frame)
Signed-off-by: softworkz <softworkz@hotmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>
Make get_int/set_int symetric. The int64_t to double to int64_t
conversion is unprecise for large value.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Anton Khirnov
Marvin Scholz
Timo Rothenpieler
James Almer
Andreas Rheinhardt
Soft Works
Zhao Zhili
Limin Wang