fixed overlay stacking bugs

diff --git a/fusefile.c b/fusefile.c
index ab97ff7f0f50c8902066075c2df1951f5c9fdb31..c8964f4d580bf1a99bd7085c9d14869b77962dbd 100644 (file)
--- a/fusefile.c
+++ b/fusefile.c
@@ -290,8 +290,9 @@ static void dup_source_item(int index) {
        fprintf( stderr, "** OOM when expanding frament table\n" );
        usage();
     }
-    memcpy( &sources.array[ index+1 ], &sources.array[ index ],
-           sizeof( struct Source ) );
+    // copy elements from [index] to [count-1] one element down
+    size_t size = ( sources.count - index - 1 ) * sizeof( struct Source ); 
+    memmove( &sources.array[ index+1 ], &sources.array[ index ], size );
 }
 
 #if DEBUG
@@ -462,28 +463,14 @@ static int find_source(off_t offset) {
     if ( offset >= sources.size ) {
        return -1;
     }
-#if DEBUG
-    fprintf( stderr, "find_source( %ld )\n", offset );
-#endif
     while ( lo + 1 < hi ) {
        int m = ( lo + hi ) / 2;
        if ( offset < sources.array[ m ].start ) {
-#if DEBUG
-           fprintf( stderr, "  offset < [%d].start: %ld\n",
-                    m, sources.array[ m ].start );
-#endif
            hi = m;
        } else {
-#if DEBUG
-           fprintf( stderr, "  offset >= [%d].start: %ld\n",
-                    m, sources.array[ m ].start );
-#endif
            lo = m;
        }
     }
-#if DEBUG
-    fprintf( stderr, "found %d\n", lo );
-#endif
     return lo;
 }
 
@@ -522,30 +509,25 @@ static int overlay_merge(char *buf,off_t beg,off_t end) {
 static int fusefile_read(const char *path, char *buf, size_t size,
                         off_t off, struct fuse_file_info *fi)
 {
-#if DEBUG
-    fprintf( stderr, "fusefile_read( %s )\n", path );
-#endif
     if( strcmp( path, "/" ) != 0 ) {
        return -ENOENT;
     }
-#if DEBUG
-    fprintf( stderr, "read %ld %ld\n", off, size );
-#endif
     size_t rr = 0; // total reading
-    while ( size > 0 ) {
 #if DEBUG
-       fprintf( stderr, "  find_source %ld %ld\n", off, size );
+    fprintf( stderr, "fusefile_read %ld + %ld\n", off, size );
 #endif
+    while ( size > 0 ) {
        int i = find_source( off );
        if ( i < 0 ) {
            return ( off == sources.size )? rr : -ENOENT;
        }
+#if DEBUG
+       fprintf( stderr, " item: %d ", i );
+       print_source(& sources.array[i] );
+#endif
        if ( sources.array[i].fd < 0 ) {
            return -ENOENT;
        }
-#if DEBUG
-       print_source( &sources.array[i] );
-#endif
        times.atime = time( 0 );
        size_t b = off - sources.array[i].start + sources.array[i].from;
        size_t n = sources.array[i].to - b;
@@ -556,20 +538,13 @@ static int fusefile_read(const char *path, char *buf, size_t size,
            fsync( sources.array[i].fd );
            sources.array[i].dirty = 0;
        }
-#if DEBUG
-       fprintf( stderr, "  seek fd=%d to %ld\n", sources.array[i].fd, b );
-#endif
        if ( lseek( sources.array[i].fd, b, SEEK_SET ) < 0 ) {
            perror( sources.array[i].filename );
            return -ENOENT;
        }
-#if DEBUG
-       fprintf( stderr, "  now read %ld from fd=%d\n",
-                n, sources.array[i].fd );
-#endif
        ssize_t r = read( sources.array[i].fd, buf + rr, n );
 #if DEBUG
-       fprintf( stderr, "  got %ld bytes\n", r );
+       fprintf( stderr, " got: %ld bytes of %ld at %ld\n", r, n, rr );
 #endif
        if ( r < 0 ) {
            perror( sources.array[i].filename );
@@ -657,29 +632,54 @@ static off_t overlay_inject_from_region(off_t beg,off_t end) {
     }
     struct Region frags[3] = {
        { sources.array[ index ].start, beg },
-       { beg, ENDSOURCE( sources.array[ index ] ) },
-       { ENDSOURCE( sources.array[ index ] ), end } };
+       { beg, end },
+       { end, ENDSOURCE( sources.array[ index ] ) } };
+#if DEBUG
+    int i;
+    for ( i = 0; i < 3; i++ ) {
+       fprintf( stderr, "frags[%d] = (%ld, %ld)\n",
+                i, frags[i].beg, frags[i].end );
+    }
+#endif
     ssize_t size = frags[0].end - frags[0].beg;
     if ( size ) {
-       // "Duplicate" the indexed source data, copying the filename
+       // Handle any portion before injection point.
        dup_source_item( index );
-       sources.array[ index ].to = sources.array[ index ].from + size;
+       off_t point = sources.array[ index ].from + size;
+       sources.array[ index ].to = point;
+#if DEBUG
+       fprintf( stderr, "item %d ", index );
+       print_source( &sources.array[ index ] );
+#endif
+       // Adjust item after injection point
        index++;
        sources.array[ index ].start = beg;
-       sources.array[ index ].from = sources.array[ index-1 ].to;
+       sources.array[ index ].from = point;
+#if DEBUG
+       fprintf( stderr, "item %d adjust ", index );
+       print_source( &sources.array[ index ] );
+#endif
     }
     size = frags[2].end        - frags[2].beg;
     if ( size ) {
+       // Handle any remaining portion following injection fragment
        dup_source_item( index );
        sources.array[ index+1 ].start = frags[2].beg;
-       sources.array[ index+1 ].from = sources.array[ index+1 ].to -size;
+       sources.array[ index+1 ].from += frags[1].end - frags[1].beg;
+#if DEBUG
+       fprintf( stderr, "item %d ", index+1 );
+       print_source( &sources.array[ index+1 ] );
+#endif
     }
-    // Replace the [index] fragment
+    // Set up the injection fragment
     sources.array[ index ].filename = overlay.source.filename;
-    sources.array[ index ].start = beg;
     sources.array[ index ].from = beg;
     sources.array[ index ].to = end;
-    sources.array[ index ].fd = overlay.source.fd; //?
+    sources.array[ index ].fd = overlay.source.fd;
+#if DEBUG
+       fprintf( stderr, "item %d ", index );
+       print_source( &sources.array[ index ] );
+#endif
     return end;
 }
 
@@ -699,9 +699,14 @@ static void overlay_inject() {
     }
     size_t count = 0;
     size_t size = sizeof( overlay.count );
-    if ( read( overlay.source.fd, &count, size ) != size ) {
-       fprintf( stderr, "** error injecting %s\n", overlay.source.filename );
-       usage();
+    size_t n;
+    if ( ( n = read( overlay.source.fd, &count, size ) ) != size ) {
+       if ( n != 0 ) {
+           fprintf( stderr, "** error injecting %s\n",
+                    overlay.source.filename );
+           usage();
+       }
+       fprintf( stderr, "** ignoring empty %s\n", overlay.source.filename );
     }
     if ( count == 0 ) {
        close( overlay.source.fd );
@@ -717,12 +722,16 @@ static void overlay_inject() {
     for ( i = 0; i < count; i++ ) {
        off_t beg = overlay.table[i].beg;
        while ( beg < overlay.table[i].end ) {
+#if DEBUG
+           fprintf( stderr, "inject [%ld,%ld] ", beg, overlay.table[i].end );
+           print_source( &overlay.source );
+#endif
+           
            beg = overlay_inject_from_region( beg, overlay.table[i].end );
        }
     }
     free( overlay.table );
     overlay.table = 0;
-    close( overlay.source.fd );
 }
 
 /**
@@ -731,7 +740,7 @@ static void overlay_inject() {
 static void overlay_post_setup() {
     char *end;
     while ( ( end = strchr( overlay.source.filename, ':' ) ) ) {
-       *end = 0; //  
+       *end = 0; //
        overlay_inject();
        overlay.source.filename = end + 1;
     }
@@ -796,7 +805,6 @@ static int fusefile_write_buf(const char *path, struct fuse_bufvec *buf,
     if ( strcmp( path, "/" ) != 0 ) {
        return -ENOENT;
     }
-
     size_t size = 0;
     int i;
     for ( i = 0; i < buf->count; i++ ) {
@@ -967,9 +975,10 @@ static int dump_fragments(int push) {
                  ENDSOURCE( sources.array[ src ] ) <= x; src++ ) {
            // Dump sources.array[src] in full
            if ( !push ) {
-               fprintf( stdout, "%s/%ld:%ld\n",
+               fprintf( stdout, "A %s/%ld:%ld\n",
                         sources.array[ src ].filename,
-                        pos - sources.array[ src ].start,
+                        pos - sources.array[ src ].start +
+                        sources.array[ src ].from,
                         sources.array[ src ].to );
            }
            pos = ENDSOURCE( sources.array[ src ] );
@@ -977,10 +986,13 @@ static int dump_fragments(int push) {
        if ( ( src < sources.count ) && ( sources.array[ src ].start < x ) ) {
            // Dump sources.array[src] up to x;
            if ( !push ) {
-               fprintf( stdout, "%s/%ld:%ld\n",
+               fprintf( stdout, "B %s/%ld:%ld\n",
                         sources.array[ src ].filename,
-                        pos - sources.array[ src ].start,
-                        x - sources.array[ src ].start );
+                        sources.array[ src ].from,
+                        //pos - sources.array[ src ].start,
+                        x - sources.array[ src ].start +
+                        sources.array[ src ].from
+                        );
            }
            pos = ENDSOURCE( sources.array[ src ] );
        }
@@ -1041,6 +1053,7 @@ static int setup_argv(int argc,char ***argv) {
     // note: (*argv)[ argc ] is the mount point argument
     char *OURS[] = {
        "-odefault_permissions",
+       //"-s", // Forced single-threading
        (*argv)[ argc ]
     };
 #define OURSN ( sizeof( OURS ) / sizeof( char* ) )