From 6e7ef5ec358c495a3c82f86d3d9d73ededa42983 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Tue, 15 Sep 2009 10:42:01 +0000
Subject: [PATCH] Probetest, to test the demuxers probe functions against
 random and not so random input.

Originally committed as revision 19853 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 tools/probetest.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)
 create mode 100644 tools/probetest.c

diff --git a/tools/probetest.c b/tools/probetest.c
new file mode 100644
index 0000000000..a49bb41454
--- /dev/null
+++ b/tools/probetest.c
@@ -0,0 +1,119 @@
+/*
+ * copyright (c) 2009 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdlib.h>
+
+#include "libavformat/avformat.h"
+#include "libavcodec/put_bits.h"
+#include "libavutil/lfg.h"
+
+static int score_array[1000]; //this must be larger than the number of formats
+static int failures=0;
+
+static void probe(AVProbeData *pd, int type, int p, int size)
+{
+    int i;
+    AVInputFormat *fmt;
+
+    for(fmt = first_iformat; fmt != NULL; fmt = fmt->next) {
+        if (fmt->flags & AVFMT_NOFILE)
+            continue;
+        if (fmt->read_probe) {
+            int score = fmt->read_probe(pd);
+            if(score > score_array[i] && score > AVPROBE_SCORE_MAX/4){
+                score_array[i]= score;
+                fprintf(stderr, "Failure of %s probing code with score=%d type=%d p=%X size=%d\n", fmt->name, score, type, p, size);
+                failures++;
+            }
+        }
+        i++;
+    }
+}
+
+int main(int argc, char **argv)
+{
+    unsigned int p, i, type, size, retry;
+    AVProbeData pd;
+    AVLFG state;
+    PutBitContext pb;
+
+    avcodec_register_all();
+    av_register_all();
+
+    av_lfg_init(&state, 0xdeadbeef);
+
+    pd.buf= NULL;
+    for(size= 1; size < 65537; size*=2){
+        pd.buf_size= size;
+        pd.buf= av_realloc(pd.buf, size + AVPROBE_PADDING_SIZE);
+        pd.filename= "";
+
+        fprintf(stderr, "testing size=%d\n", size);
+
+        for(retry=0; retry<4097; retry+= FFMAX(size,32)){
+            for(type=0; type < 4; type++){
+                for(p=0; p<4096; p++){
+                    unsigned hist=0;
+                    init_put_bits(&pb, pd.buf, size);
+                    switch(type){
+                    case 0:
+                        for(i=0; i<size*8; i++){
+                            put_bits(&pb, 1, (av_lfg_get(&state)&0xFFFFFFFF) > p<<20);
+                        }
+                        break;
+                    case 1:
+                        for(i=0; i<size*8; i++){
+                            unsigned int p2= hist ? p&0x3F : (p>>6);
+                            unsigned int v= (av_lfg_get(&state)&0xFFFFFFFF) > p2<<26;
+                            put_bits(&pb, 1, v);
+                            hist= v;
+                        }
+                        break;
+                    case 2:
+                        for(i=0; i<size*8; i++){
+                            unsigned int p2= (p >> (hist*3)) & 7;
+                            unsigned int v= (av_lfg_get(&state)&0xFFFFFFFF) > p2<<29;
+                            put_bits(&pb, 1, v);
+                            hist= (2*hist + v)&3;
+                        }
+                        break;
+                    case 3:
+                        for(i=0; i<size; i++){
+                            int c=0;
+                            while(p&63){
+                                c= (av_lfg_get(&state)&0xFFFFFFFF)>>24;
+                                if     (c >= 'a' && c <= 'z' && (p&1)) break;
+                                else if(c >= 'A' && c <= 'Z' && (p&2)) break;
+                                else if(c >= '0' && c <= '9' && (p&4)) break;
+                                else if(c == ' '&& (p&8)) break;
+                                else if(c == 0 && (p&16)) break;
+                                else if(c == 1 && (p&32)) break;
+                            }
+                            pd.buf[i]= c;
+                        }
+                    }
+                    flush_put_bits(&pb);
+                    probe(&pd, type, p, size);
+                }
+            }
+        }
+    }
+    return failures;
+}