Added -push action, to push overlay data into source fragments.

diff --git a/fusefile.8 b/fusefile.8
index 6af36f49202ba1dc85f3e20690e54d8646ab0582..194f4aa83558057c4c62d859dbab9a2219445940 100644 (file)
--- a/fusefile.8
+++ b/fusefile.8
@@ -8,6 +8,8 @@ fusefile, fusedisk \- FUSE file mount for combining file fragments
 .br
 .B fusefile \fB-dump\fR \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ...
 .br
+.B fusefile \fB-push\fR \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ...
+.br
 .B fusedisk \fR[\fIfuse-opts\fR] \fBmountpoint\fR \fR[\fIoverlay\fR] \fIfilename/from-to\fR ...
 
 .SH DESCRIPTION
@@ -33,12 +35,18 @@ from the fragments.
 
 The option \fB-dump\fR as first argument together with a fusefile
 setup will print the setup to standard output rather than establishing
-a fusefile mount. This is of most use with a prior overlay setup,
-where then the printout includes the portions of updates that have
-been captured in the overlay. The printout is the series of fusefile
+a fusefile mount. This is of most use with a prior overlay setup where
+then the printout includes the portions of updates that have been
+captured in the overlay. The printout is the series of fusefile
 fragment argments to give in order to intersperse the captured overlay
 portions according to the overlay table.
 
+The option \fB-push\fR as first argument together with a fusefile
+setup will push the overlay into the sources (except for
+write-protected fragments). This is only of use with a prior overlay
+setup where then the updates that have been captured in the overlay
+get pushed into the fragments.
+
 \fBfusedisk\fR is a helper script to set up a \fBfusefile\fR as a
 block device (via \fIfuseblk\fR) by using the device mapper
 (\fBdmsetup\fR) to manage an empty block device mapping where content

diff --git a/fusefile.c b/fusefile.c
index 9e5cb45d835b771e73548b8b443461474fcaa487..69750fad1507d9db3626b9927bac2bb642235ab2 100644 (file)
--- a/fusefile.c
+++ b/fusefile.c
@@ -717,6 +717,40 @@ static int fusefile_write(const char *path, const char *buf, size_t size,
     return size;
 }
 
+#define PUSHBUF 104857600
+/**
+ * Write data from overlay to source.
+ */
+static void push_oly(off_t beg, off_t end) {
+    static char * buffer = 0;
+    // Pretend that there isn't an overlay
+    char *filename = overlay.source.filename;
+    if ( buffer == 0 ) {
+       buffer = malloc( PUSHBUF );
+       if ( buffer == 0 ) {
+           fprintf( stderr, "** OOM!!\n" );
+           exit( 1 );
+       }
+    }
+    overlay.source.filename = 0;
+    while ( beg < end ) {
+       off_t size = end - beg;
+       if ( size > PUSHBUF ) {
+           size = PUSHBUF;
+       }
+       if ( lseek( overlay.source.fd, beg, SEEK_SET ) < 0 ) {
+           fprintf( stderr, "** Cannot seek overlay at %ld\n", beg );
+           break;
+       }
+       size = read( overlay.source.fd, buffer, size );
+       if ( write_block( beg, buffer, size ) < 0 ) {
+           fprintf( stderr, "** Cannot push %ld bytes at %ld\n", size, beg );
+       }
+       beg += size;
+    }
+    overlay.source.filename = filename;
+}
+
 static void fusefile_destroy(void *data) {
     char *mnt = (char*) data; // As passed to fuse_main
 #if DEBUG
@@ -804,7 +838,7 @@ void *fusefile_init(struct fuse_conn_info *fci) {
 /**
  * Dump the current fragmentation to stdout.
  */
-static int dump_fragments() {
+static int dump_fragments(int push) {
     int oly = 0;
     int src = 0;
     size_t pos = 0;
@@ -814,25 +848,33 @@ static int dump_fragments() {
        for ( ; src < sources.count && 
                  ENDSOURCE( sources.array[ src ] ) <= x; src++ ) {
            // Dump sources.array[src] in full
-           fprintf( stdout, "%s/%ld:%ld\n",
-                    sources.array[ src ].filename,
-                    pos - sources.array[ src ].start,
-                    sources.array[ src ].to );
+           if ( !push ) {
+               fprintf( stdout, "%s/%ld:%ld\n",
+                        sources.array[ src ].filename,
+                        pos - sources.array[ src ].start,
+                        sources.array[ src ].to );
+           }
            pos = ENDSOURCE( sources.array[ src ] );
        }
        if ( ( src < sources.count ) && ( sources.array[ src ].start < x ) ) {
            // Dump sources.array[src] up to x;
-           fprintf( stdout, "%s/%ld:%ld\n",
-                    sources.array[ src ].filename,
-                    pos - sources.array[ src ].start,
-                    x - sources.array[ src ].start );
+           if ( !push ) {
+               fprintf( stdout, "%s/%ld:%ld\n",
+                        sources.array[ src ].filename,
+                        pos - sources.array[ src ].start,
+                        x - sources.array[ src ].start );
+           }
            pos = ENDSOURCE( sources.array[ src ] );
        }
        if ( oly < overlay.count ) {
-           fprintf( stdout, "%s/%ld:%ld\n",
-                    overlay.source.filename,
-                    overlay.table[ oly ].beg,
-                    overlay.table[ oly ].end );
+           if ( !push ) {
+               fprintf( stdout, "%s/%ld:%ld\n",
+                        overlay.source.filename,
+                        overlay.table[ oly ].beg,
+                        overlay.table[ oly ].end );
+           } else {
+               push_oly( overlay.table[ oly ].beg, overlay.table[ oly ].end );
+           }
            pos = overlay.table[ oly++ ].end;
        }
        for ( ; src < sources.count &&
@@ -975,7 +1017,10 @@ int main(int argc, char *argv[])
     }
     fuseargc = setup_argv( fuseargc, &argv );
     if ( strcmp( "-dump", argv[ 1 ] ) == 0 ) {
-       return dump_fragments();
+       return dump_fragments( 0 );
+    }
+    if ( strcmp( "-push", argv[ 1 ] ) == 0 ) {
+       return dump_fragments( 1 );
     }
     struct fuse_args args = FUSE_ARGS_INIT( fuseargc, argv );
     if ( fuse_parse_cmdline( &args, &mnt, &mt, &fg ) ) {