Roughly implemented automatic .wav extraction in cdrskin

libburn/libdax_audioxtr.c

@@ -27,7 +27,7 @@ extern struct libdax_msgs *libdax_messenger;
 
 int libdax_audioxtr_new(struct libdax_audioxtr **xtr, char *path, int flag)
 {
- int ret;
+ int ret= -1;
  struct libdax_audioxtr *o;
 
  o= *xtr= (struct libdax_audioxtr *) malloc(sizeof(struct libdax_audioxtr));
@@ -45,12 +45,12 @@ int libdax_audioxtr_new(struct libdax_audioxtr **xtr, char *path, int flag)
 
  ret= libdax_audioxtr_open(o,0);
  if(ret<=0)
-   goto failure;
+   {ret= -2*(ret<0); goto failure;}
 
  return(1);
 failure:
  libdax_audioxtr_destroy(xtr,0);
- return(-1);
+ return(ret);
 }
 
 
@@ -197,3 +197,24 @@ int libdax_audioxtr_read(struct libdax_audioxtr *o,
  return(ret);
 }
 
+
+int libdax_audioxtr_detach_fd(struct libdax_audioxtr *o, int *fd, int flag)
+{
+ if(o->fd<0)
+   return(-1);
+ if(strcmp(o->fmt,".wav")!=0)
+   return(0);
+ if(flag&1) {
+   *fd= o->fd;
+ } else {
+   *fd= dup(o->fd);
+   if(*fd>=0 && strcmp(o->path,"-")!=0)
+     close(o->fd);
+ }
+ if(*fd>=0) {
+   o->fd= -1;
+   return(1);
+ }
+ return(-1);
+}
+

libburn/libdax_audioxtr.h

@@ -9,6 +9,7 @@
 
                             /* Public Macros */
 
+/* Maximum size for address paths and fmt_info strings */
 #define LIBDAX_AUDIOXTR_STRLEN 4096
 
 
@@ -35,7 +36,10 @@ struct libdax_audioxtr;
     @param path Address of the audio file to extract. "-" is stdin (but might
                 be not suitable for all futurely supported formats).
     @param flag Bitfield for control purposes (unused yet, submit 0)
-    @return >0 success, <=0 failure
+    @return >0 success
+             0 unsuitable format
+            -1 severe error
+            -2 path not found
 */
 int libdax_audioxtr_new(struct libdax_audioxtr **xtr, char *path, int flag);
 
@@ -71,6 +75,21 @@ int libdax_audioxtr_read(struct libdax_audioxtr *xtr,
                          char buffer[], int buffer_size, int flag);
 
 
+/** Try to obtain a file descriptor which will deliver extracted data
+    to normal calls of read(2). This may fail because the format is
+    unsuitable for that, but ".wav" is ok. If this call succeeds the xtr
+    object will have forgotten its file descriptor and libdax_audioxtr_read()
+    will return a usage error. One may use *fd after libdax_audioxtr_destroy()
+    and will have to close it via close(2) when done with it.
+    @param xtr Opaque handle to extractor
+    @param fd Eventually returns the file descriptor number
+    @param flag Bitfield for control purposes
+                bit0= do not dup(2) and close(2) but hand out original fd
+    @return 1 success, 0 cannot hand out fd , -1 severe error
+*/
+int libdax_audioxtr_detach_fd(struct libdax_audioxtr *o, int *fd, int flag);
+
+
 /** Clean up after extraction and destroy extractor object.
     @param xtr Opaque handle to extractor, *xtr is allowed to be NULL,
                *xtr is set to NULL by this function