[FFmpeg-devel] [PATCH 3/4] avformat/avisynth: remove library allocation from global state

Stephen Hutchinson qyot27 at gmail.com
Tue Aug 13 22:19:59 EEST 2024


On 7/29/24 12:43 AM, Stephen Hutchinson wrote:
> As part of this, the mutexes are no longer necessary, and
> avisynth_read_close needs to check that avs->avs_library.library
> still exists before it attempts to call avisynth_context_destroy
> and dlclose.
> 
> Signed-off-by: Stephen Hutchinson <qyot27 at gmail.com>
> ---
>   libavformat/avisynth.c | 133 ++++++++++++++++++++---------------------
>   1 file changed, 64 insertions(+), 69 deletions(-)
> 
> diff --git a/libavformat/avisynth.c b/libavformat/avisynth.c
> index b01263e010..b91d77b8d8 100644
> --- a/libavformat/avisynth.c
> +++ b/libavformat/avisynth.c
> @@ -115,6 +115,7 @@ typedef struct AviSynthContext {
>       int error;
>   
>       uint32_t flags;
> +    struct AviSynthLibrary avs_library;
>   } AviSynthContext;
>   
>   static const int avs_planes_packed[1] = { 0 };
> @@ -128,20 +129,16 @@ static const int avs_planes_yuva[4]   = { AVS_PLANAR_Y, AVS_PLANAR_U,
>   static const int avs_planes_rgba[4]   = { AVS_PLANAR_G, AVS_PLANAR_B,
>                                             AVS_PLANAR_R, AVS_PLANAR_A };
>   
> -static AVMutex avisynth_mutex = AV_MUTEX_INITIALIZER;
> -
> -static AviSynthLibrary avs_library;
> -
> -static av_cold int avisynth_load_library(void)
> +static av_cold int avisynth_load_library(AviSynthContext *avs)
>   {
> -    avs_library.library = dlopen(AVISYNTH_LIB, RTLD_NOW | RTLD_LOCAL);
> -    if (!avs_library.library)
> +    avs->avs_library.library = dlopen(AVISYNTH_LIB, RTLD_NOW | RTLD_LOCAL);
> +    if (!avs->avs_library.library)
>           return AVERROR_UNKNOWN;
>   
>   #define LOAD_AVS_FUNC(name, continue_on_fail)                          \
> -        avs_library.name = (name ## _func)                             \
> -                           dlsym(avs_library.library, #name);          \
> -        if (!continue_on_fail && !avs_library.name)                    \
> +        avs->avs_library.name = (name ## _func)                             \
> +                           dlsym(avs->avs_library.library, #name);          \
> +        if (!continue_on_fail && !avs->avs_library.name)                    \
>               goto fail;
>   
>       LOAD_AVS_FUNC(avs_bit_blt, 0);
> @@ -177,7 +174,7 @@ static av_cold int avisynth_load_library(void)
>       return 0;
>   
>   fail:
> -    dlclose(avs_library.library);
> +    dlclose(avs->avs_library.library);
>       return AVERROR_UNKNOWN;
>   }
>   
> @@ -189,13 +186,13 @@ static av_cold int avisynth_context_create(AVFormatContext *s)
>       AviSynthContext *avs = s->priv_data;
>       int ret;
>   
> -    if (!avs_library.library)
> -        if (ret = avisynth_load_library())
> +    if (!avs->avs_library.library)
> +        if (ret = avisynth_load_library(avs))
>               return ret;
>   
> -    avs->env = avs_library.avs_create_script_environment(3);
> -    if (avs_library.avs_get_error) {
> -        const char *error = avs_library.avs_get_error(avs->env);
> +    avs->env = avs->avs_library.avs_create_script_environment(3);
> +    if (avs->avs_library.avs_get_error) {
> +        const char *error = avs->avs_library.avs_get_error(avs->env);
>           if (error) {
>               av_log(s, AV_LOG_ERROR, "%s\n", error);
>               return AVERROR_UNKNOWN;
> @@ -208,11 +205,11 @@ static av_cold int avisynth_context_create(AVFormatContext *s)
>   static av_cold void avisynth_context_destroy(AviSynthContext *avs)
>   {
>       if (avs->clip) {
> -        avs_library.avs_release_clip(avs->clip);
> +        avs->avs_library.avs_release_clip(avs->clip);
>           avs->clip = NULL;
>       }
>       if (avs->env) {
> -        avs_library.avs_delete_script_environment(avs->env);
> +        avs->avs_library.avs_delete_script_environment(avs->env);
>           avs->env = NULL;
>       }
>   }
> @@ -486,17 +483,17 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>        * version 9 at the minimum.  Technically, 8.1 works, but the time
>        * distance between 8.1 and 9 is very small, so just restrict it to 9. */
>   
> -    if (avs_library.avs_get_version(avs->clip) >= 9) {
> +    if (avs->avs_library.avs_get_version(avs->clip) >= 9) {
>   
> -        frame  = avs_library.avs_get_frame(avs->clip, 0);
> -        avsmap = avs_library.avs_get_frame_props_ro(avs->env, frame);
> +        frame  = avs->avs_library.avs_get_frame(avs->clip, 0);
> +        avsmap = avs->avs_library.avs_get_frame_props_ro(avs->env, frame);
>   
>           /* Field order */
>           if(avs->flags & AVISYNTH_FRAMEPROP_FIELD_ORDER) {
> -            if(avs_library.avs_prop_get_type(avs->env, avsmap, "_FieldBased") == AVS_PROPTYPE_UNSET) {
> +            if(avs->avs_library.avs_prop_get_type(avs->env, avsmap, "_FieldBased") == AVS_PROPTYPE_UNSET) {
>                   st->codecpar->field_order = AV_FIELD_UNKNOWN;
>               } else {
> -                switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_FieldBased", 0, &error)) {
> +                switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_FieldBased", 0, &error)) {
>                   case 0:
>                       st->codecpar->field_order = AV_FIELD_PROGRESSIVE;
>                       break;
> @@ -514,10 +511,10 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Color Range */
>           if(avs->flags & AVISYNTH_FRAMEPROP_RANGE) {
> -            if(avs_library.avs_prop_get_type(avs->env, avsmap, "_ColorRange") == AVS_PROPTYPE_UNSET) {
> +            if(avs->avs_library.avs_prop_get_type(avs->env, avsmap, "_ColorRange") == AVS_PROPTYPE_UNSET) {
>                   st->codecpar->color_range = AVCOL_RANGE_UNSPECIFIED;
>               } else {
> -                switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_ColorRange", 0, &error)) {
> +                switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_ColorRange", 0, &error)) {
>                   case 0:
>                       st->codecpar->color_range = AVCOL_RANGE_JPEG;
>                       break;
> @@ -532,7 +529,7 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Color Primaries */
>           if(avs->flags & AVISYNTH_FRAMEPROP_PRIMARIES) {
> -            switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_Primaries", 0, &error)) {
> +            switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_Primaries", 0, &error)) {
>               case 1:
>                   st->codecpar->color_primaries = AVCOL_PRI_BT709;
>                   break;
> @@ -576,7 +573,7 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Color Transfer Characteristics */
>           if(avs->flags & AVISYNTH_FRAMEPROP_TRANSFER) {
> -            switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_Transfer", 0, &error)) {
> +            switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_Transfer", 0, &error)) {
>               case 1:
>                   st->codecpar->color_trc = AVCOL_TRC_BT709;
>                   break;
> @@ -635,10 +632,10 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Matrix coefficients */
>           if(avs->flags & AVISYNTH_FRAMEPROP_MATRIX) {
> -            if(avs_library.avs_prop_get_type(avs->env, avsmap, "_Matrix") == AVS_PROPTYPE_UNSET) {
> +            if(avs->avs_library.avs_prop_get_type(avs->env, avsmap, "_Matrix") == AVS_PROPTYPE_UNSET) {
>                   st->codecpar->color_space = AVCOL_SPC_UNSPECIFIED;
>               } else {
> -                switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_Matrix", 0, &error)) {
> +                switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_Matrix", 0, &error)) {
>                   case 0:
>                       st->codecpar->color_space = AVCOL_SPC_RGB;
>                       break;
> @@ -689,10 +686,10 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Chroma Location */
>           if(avs->flags & AVISYNTH_FRAMEPROP_CHROMA_LOCATION) {
> -            if(avs_library.avs_prop_get_type(avs->env, avsmap, "_ChromaLocation") == AVS_PROPTYPE_UNSET) {
> +            if(avs->avs_library.avs_prop_get_type(avs->env, avsmap, "_ChromaLocation") == AVS_PROPTYPE_UNSET) {
>                   st->codecpar->chroma_location = AVCHROMA_LOC_UNSPECIFIED;
>               } else {
> -                switch (avs_library.avs_prop_get_int(avs->env, avsmap, "_ChromaLocation", 0, &error)) {
> +                switch (avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_ChromaLocation", 0, &error)) {
>                   case 0:
>                       st->codecpar->chroma_location = AVCHROMA_LOC_LEFT;
>                       break;
> @@ -719,12 +716,12 @@ static int avisynth_create_stream_video(AVFormatContext *s, AVStream *st)
>   
>           /* Sample aspect ratio */
>           if(avs->flags & AVISYNTH_FRAMEPROP_SAR) {
> -            sar_num = avs_library.avs_prop_get_int(avs->env, avsmap, "_SARNum", 0, &error);
> -            sar_den = avs_library.avs_prop_get_int(avs->env, avsmap, "_SARDen", 0, &error);
> +            sar_num = avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_SARNum", 0, &error);
> +            sar_den = avs->avs_library.avs_prop_get_int(avs->env, avsmap, "_SARDen", 0, &error);
>               st->sample_aspect_ratio = (AVRational){ sar_num, sar_den };
>           }
>   
> -        avs_library.avs_release_video_frame(frame);
> +        avs->avs_library.avs_release_video_frame(frame);
>       } else {
>           st->codecpar->field_order = AV_FIELD_UNKNOWN;
>           /* AviSynth works with frame-based video, detecting field order can
> @@ -753,9 +750,9 @@ static int avisynth_create_stream_audio(AVFormatContext *s, AVStream *st)
>       st->duration                        = avs->vi->num_audio_samples;
>       avpriv_set_pts_info(st, 64, 1, avs->vi->audio_samples_per_second);
>   
> -    if (avs_library.avs_get_version(avs->clip) >= 10)
> +    if (avs->avs_library.avs_get_version(avs->clip) >= 10)
>           av_channel_layout_from_mask(&st->codecpar->ch_layout,
> -                                    avs_library.avs_get_channel_mask(avs->vi));
> +                                    avs->avs_library.avs_get_channel_mask(avs->vi));
>   
>       switch (avs->vi->sample_type) {
>       case AVS_SAMPLE_INT8:
> @@ -817,13 +814,13 @@ static int avisynth_open_file(AVFormatContext *s)
>       if (ret = avisynth_context_create(s))
>           return ret;
>   
> -    if (!avs_library.avs_check_version(avs->env, 7)) {
> +    if (!avs->avs_library.avs_check_version(avs->env, 7)) {
>           AVS_Value args[] = {
>               avs_new_value_string(s->url),
>               avs_new_value_bool(1) // filename is in UTF-8
>           };
> -        val = avs_library.avs_invoke(avs->env, "Import",
> -                                     avs_new_value_array(args, 2), 0);
> +        val = avs->avs_library.avs_invoke(avs->env, "Import",
> +                                          avs_new_value_array(args, 2), 0);
>       } else {
>           AVS_Value arg;
>   #ifdef _WIN32
> @@ -837,7 +834,7 @@ static int avisynth_open_file(AVFormatContext *s)
>   #else
>           arg = avs_new_value_string(s->url);
>   #endif
> -        val = avs_library.avs_invoke(avs->env, "Import", arg, 0);
> +        val = avs->avs_library.avs_invoke(avs->env, "Import", arg, 0);
>   #ifdef _WIN32
>           av_free(filename_ansi);
>   #endif
> @@ -854,14 +851,14 @@ static int avisynth_open_file(AVFormatContext *s)
>           goto fail;
>       }
>   
> -    avs->clip = avs_library.avs_take_clip(val, avs->env);
> -    avs->vi   = avs_library.avs_get_video_info(avs->clip);
> +    avs->clip = avs->avs_library.avs_take_clip(val, avs->env);
> +    avs->vi   = avs->avs_library.avs_get_video_info(avs->clip);
>   
>       /* On Windows, FFmpeg supports AviSynth interface version 6 or higher.
>        * This includes AviSynth 2.6 RC1 or higher, and AviSynth+ r1718 or higher,
>        * and excludes 2.5 and the 2.6 alphas. */
>   
> -    if (avs_library.avs_get_version(avs->clip) < 6) {
> +    if (avs->avs_library.avs_get_version(avs->clip) < 6) {
>           av_log(s, AV_LOG_ERROR,
>                  "AviSynth version is too old. Please upgrade to either AviSynth 2.6 >= RC1 or AviSynth+ >= r1718.\n");
>           ret = AVERROR_UNKNOWN;
> @@ -869,7 +866,7 @@ static int avisynth_open_file(AVFormatContext *s)
>       }
>   
>       /* Release the AVS_Value as it will go out of scope. */
> -    avs_library.avs_release_value(val);
> +    avs->avs_library.avs_release_value(val);
>   
>       if (ret = avisynth_create_stream(s))
>           goto fail;
> @@ -917,7 +914,7 @@ static int avisynth_read_packet_video(AVFormatContext *s, AVPacket *pkt,
>       if (discard)
>           return 0;
>   
> -    bits = avs_library.avs_bits_per_pixel(avs->vi);
> +    bits = avs->avs_library.avs_bits_per_pixel(avs->vi);
>   
>       /* Without the cast to int64_t, calculation overflows at about 9k x 9k
>        * resolution. */
> @@ -934,8 +931,8 @@ static int avisynth_read_packet_video(AVFormatContext *s, AVPacket *pkt,
>       pkt->duration = 1;
>       pkt->stream_index = avs->curr_stream;
>   
> -    frame = avs_library.avs_get_frame(avs->clip, n);
> -    error = avs_library.avs_clip_get_error(avs->clip);
> +    frame = avs->avs_library.avs_get_frame(avs->clip, n);
> +    error = avs->avs_library.avs_clip_get_error(avs->clip);
>       if (error) {
>           av_log(s, AV_LOG_ERROR, "%s\n", error);
>           avs->error = 1;
> @@ -946,26 +943,26 @@ static int avisynth_read_packet_video(AVFormatContext *s, AVPacket *pkt,
>       dst_p = pkt->data;
>       for (i = 0; i < avs->n_planes; i++) {
>           plane = avs->planes[i];
> -        src_p = avs_library.avs_get_read_ptr_p(frame, plane);
> -        pitch = avs_library.avs_get_pitch_p(frame, plane);
> +        src_p = avs->avs_library.avs_get_read_ptr_p(frame, plane);
> +        pitch = avs->avs_library.avs_get_pitch_p(frame, plane);
>   
> -        rowsize     = avs_library.avs_get_row_size_p(frame, plane);
> -        planeheight = avs_library.avs_get_height_p(frame, plane);
> +        rowsize     = avs->avs_library.avs_get_row_size_p(frame, plane);
> +        planeheight = avs->avs_library.avs_get_height_p(frame, plane);
>   
>           /* Flip RGB video. */
> -        if (avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR)   ||
> -            avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR48) ||
> -            avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR64)) {
> +        if (avs->avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR)   ||
> +            avs->avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR48) ||
> +            avs->avs_library.avs_is_color_space(avs->vi, AVS_CS_BGR64)) {
>               src_p = src_p + (planeheight - 1) * pitch;
>               pitch = -pitch;
>           }
>   
> -        avs_library.avs_bit_blt(avs->env, dst_p, rowsize, src_p, pitch,
> -                                 rowsize, planeheight);
> +        avs->avs_library.avs_bit_blt(avs->env, dst_p, rowsize, src_p, pitch,
> +                                     rowsize, planeheight);
>           dst_p += rowsize * planeheight;
>       }
>   
> -    avs_library.avs_release_video_frame(frame);
> +    avs->avs_library.avs_release_video_frame(frame);
>       return 0;
>   }
>   
> @@ -1025,8 +1022,8 @@ static int avisynth_read_packet_audio(AVFormatContext *s, AVPacket *pkt,
>       pkt->duration = samples;
>       pkt->stream_index = avs->curr_stream;
>   
> -    avs_library.avs_get_audio(avs->clip, pkt->data, n, samples);
> -    error = avs_library.avs_clip_get_error(avs->clip);
> +    avs->avs_library.avs_get_audio(avs->clip, pkt->data, n, samples);
> +    error = avs->avs_library.avs_clip_get_error(avs->clip);
>       if (error) {
>           av_log(s, AV_LOG_ERROR, "%s\n", error);
>           avs->error = 1;
> @@ -1040,16 +1037,9 @@ static av_cold int avisynth_read_header(AVFormatContext *s)
>   {
>       int ret;
>   
> -    // Calling library must implement a lock for thread-safe opens.
> -    if (ff_mutex_lock(&avisynth_mutex))
> -        return AVERROR_UNKNOWN;
> -
> -    if (ret = avisynth_open_file(s)) {
> -        ff_mutex_unlock(&avisynth_mutex);
> +    if (ret = avisynth_open_file(s))
>           return ret;
> -    }
>   
> -    ff_mutex_unlock(&avisynth_mutex);
>       return 0;
>   }
>   
> @@ -1085,8 +1075,13 @@ static int avisynth_read_packet(AVFormatContext *s, AVPacket *pkt)
>   
>   static av_cold int avisynth_read_close(AVFormatContext *s)
>   {
> -    avisynth_context_destroy(s->priv_data);
> -    dlclose(avs_library.library);
> +    AviSynthContext *avs = s->priv_data;
> +
> +    if (avs->avs_library.library) {
> +        avisynth_context_destroy(s->priv_data);
> +        dlclose(avs->avs_library.library);
> +    }
> +
>       return 0;
>   }
>   

Pushed.


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