X-Git-Url: http://woldlab.caltech.edu/gitweb/?p=tabix.git;a=blobdiff_plain;f=bgzf.c;h=94e6194700f6d9f633939804a7bade4bf58c9df2;hp=7a936a89819176181e23e511a437a12892fbe310;hb=3be5ff47495762af7f2ebec145bc8f9c7674593d;hpb=f14cecb6523bd4275c2858c2d54167c94db25ede

diff --git a/bgzf.c b/bgzf.c
index 7a936a8..94e6194 100644
--- a/bgzf.c
+++ b/bgzf.c
@@ -111,6 +111,32 @@ report_error(BGZF* fp, const char* message) {
     fp->error = message;
 }
 
+int is_bgzipped(const char *fn)
+{
+    BGZF *fp;
+    uint8_t buf[10],magic[10]="\037\213\010\4\0\0\0\0\0\377";
+    int n;
+
+    if ((fp = bgzf_open(fn, "r")) == 0) 
+    {
+        fprintf(stderr, "[is_bgzipped] failed to open the file: %s\n",fn);
+        return -1;
+    }
+
+#ifdef _USE_KNETFILE
+    n = knet_read(fp->x.fpr, buf, 10);
+#else
+    n = fread(buf, 1, 10, fp->file);
+#endif
+    bgzf_close(fp);
+
+    if ( n!=10 ) 
+        return -1;
+
+    if ( !memcmp(magic, buf, 10) ) return 1;
+    return 0;
+}
+
 static BGZF *bgzf_read_init()
 {
 	BGZF *fp;