avcodec/lcldec: Use ff_inflate_init/end(), cleanup generically

Returns better error messages in case of error and deduplicates
the inflateInit() code and also allows to cleanup generically
in case of errors as it is save to call ff_inflate_end() if
ff_inflate_init() has not been called successfully.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

configure

@@ -2990,7 +2990,7 @@ xma1_decoder_select="wmapro_decoder"
 xma2_decoder_select="wmapro_decoder"
 ylc_decoder_select="bswapdsp"
 zerocodec_decoder_select="inflate_wrapper"
-zlib_decoder_deps="zlib"
+zlib_decoder_select="inflate_wrapper"
 zlib_encoder_deps="zlib"
 zmbv_decoder_select="inflate_wrapper"
 zmbv_encoder_deps="zlib"

libavcodec/lcldec.c

@@ -51,6 +51,7 @@
 #include "thread.h"
 
 #if CONFIG_ZLIB_DECODER
+#include "zlib_wrapper.h"
 #include <zlib.h>
 #endif
 
@@ -66,7 +67,7 @@ typedef struct LclDecContext {
     // Decompression buffer
     unsigned char* decomp_buf;
 #if CONFIG_ZLIB_DECODER
-    z_stream zstream;
+    FFZStream zstream;
 #endif
 } LclDecContext;
 
@@ -133,26 +134,27 @@ static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsign
 static int zlib_decomp(AVCodecContext *avctx, const uint8_t *src, int src_len, int offset, int expected)
 {
     LclDecContext *c = avctx->priv_data;
-    int zret = inflateReset(&c->zstream);
+    z_stream *const zstream = &c->zstream.zstream;
+    int zret = inflateReset(zstream);
     if (zret != Z_OK) {
         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
         return AVERROR_UNKNOWN;
     }
-    c->zstream.next_in = src;
-    c->zstream.avail_in = src_len;
-    c->zstream.next_out = c->decomp_buf + offset;
-    c->zstream.avail_out = c->decomp_size - offset;
-    zret = inflate(&c->zstream, Z_FINISH);
+    zstream->next_in   = src;
+    zstream->avail_in  = src_len;
+    zstream->next_out  = c->decomp_buf + offset;
+    zstream->avail_out = c->decomp_size - offset;
+    zret = inflate(zstream, Z_FINISH);
     if (zret != Z_OK && zret != Z_STREAM_END) {
         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
         return AVERROR_UNKNOWN;
     }
-    if (expected != (unsigned int)c->zstream.total_out) {
+    if (expected != (unsigned int)zstream->total_out) {
         av_log(avctx, AV_LOG_ERROR, "Decoded size differs (%d != %lu)\n",
-               expected, c->zstream.total_out);
+               expected, zstream->total_out);
         return AVERROR_UNKNOWN;
     }
-    return c->zstream.total_out;
+    return zstream->total_out;
 }
 #endif
 
@@ -608,18 +610,8 @@ static av_cold int decode_init(AVCodecContext *avctx)
 
     /* If needed init zlib */
 #if CONFIG_ZLIB_DECODER
-    if (avctx->codec_id == AV_CODEC_ID_ZLIB) {
-        int zret;
-        c->zstream.zalloc = Z_NULL;
-        c->zstream.zfree = Z_NULL;
-        c->zstream.opaque = Z_NULL;
-        zret = inflateInit(&c->zstream);
-        if (zret != Z_OK) {
-            av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
-            av_freep(&c->decomp_buf);
-            return AVERROR_UNKNOWN;
-        }
-    }
+    if (avctx->codec_id == AV_CODEC_ID_ZLIB)
+        return ff_inflate_init(&c->zstream, avctx);
 #endif
 
     return 0;
@@ -631,8 +623,7 @@ static av_cold int decode_end(AVCodecContext *avctx)
 
     av_freep(&c->decomp_buf);
 #if CONFIG_ZLIB_DECODER
-    if (avctx->codec_id == AV_CODEC_ID_ZLIB)
-        inflateEnd(&c->zstream);
+    ff_inflate_end(&c->zstream);
 #endif
 
     return 0;
@@ -649,7 +640,7 @@ const AVCodec ff_mszh_decoder = {
     .close          = decode_end,
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
-    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 };
 #endif
 
@@ -664,6 +655,6 @@ const AVCodec ff_zlib_decoder = {
     .close          = decode_end,
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
-    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
 };
 #endif