tools/target_bsf_fuzzer: simplify the loop feeding packets to the filter

And use a single AVPacket for the entire process.
This more closely follows the suggested API usage in the doxy.

Signed-off-by: James Almer <jamrial@gmail.com>

tools/target_bsf_fuzzer.c

@@ -43,7 +43,7 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
     const uint8_t *last = data;
     const uint8_t *end = data + size;
     AVBSFContext *bsf = NULL;
-    AVPacket *in, *out;
+    AVPacket *pkt;
     uint64_t keyframes = 0;
     uint64_t flushpattern = -1;
     int res;
@@ -118,9 +118,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         return 0; // Failure of av_bsf_init() does not imply that a issue was found
     }
 
-    in = av_packet_alloc();
-    out = av_packet_alloc();
-    if (!in || !out)
+    pkt = av_packet_alloc();
+    if (!pkt)
         error("Failed memory allocation");
 
     while (data < end) {
@@ -133,11 +132,11 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (data + sizeof(fuzz_tag) > end)
             data = end;
 
-        res = av_new_packet(in, data - last);
+        res = av_new_packet(pkt, data - last);
         if (res < 0)
             error("Failed memory allocation");
-        memcpy(in->data, last, data - last);
-        in->flags = (keyframes & 1) * AV_PKT_FLAG_DISCARD + (!!(keyframes & 2)) * AV_PKT_FLAG_KEY;
+        memcpy(pkt->data, last, data - last);
+        pkt->flags = (keyframes & 1) * AV_PKT_FLAG_DISCARD + (!!(keyframes & 2)) * AV_PKT_FLAG_KEY;
         keyframes = (keyframes >> 2) + (keyframes<<62);
         data += sizeof(fuzz_tag);
         last = data;
@@ -146,28 +145,20 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
             av_bsf_flush(bsf);
         flushpattern = (flushpattern >> 3) + (flushpattern << 61);
 
-        while (in->size) {
-            res = av_bsf_send_packet(bsf, in);
-            if (res < 0 && res != AVERROR(EAGAIN))
-                break;
-            res = av_bsf_receive_packet(bsf, out);
-            if (res < 0)
-                break;
-            av_packet_unref(out);
+        res = av_bsf_send_packet(bsf, pkt);
+        if (res < 0) {
+            av_packet_unref(pkt);
+            continue;
         }
-        av_packet_unref(in);
+        while (av_bsf_receive_packet(bsf, pkt) >= 0)
+            av_packet_unref(pkt);
     }
 
-    res = av_bsf_send_packet(bsf, NULL);
-    while (!res) {
-        res = av_bsf_receive_packet(bsf, out);
-        if (res < 0)
-            break;
-        av_packet_unref(out);
-    }
+    av_bsf_send_packet(bsf, NULL);
+    while (av_bsf_receive_packet(bsf, pkt) >= 0)
+        av_packet_unref(pkt);
 
-    av_packet_free(&in);
-    av_packet_free(&out);
+    av_packet_free(&pkt);
     av_bsf_free(&bsf);
     return 0;
 }