X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;f=fusefile.c;h=a1bf2bd926792844ecee3c989dd131da641d69e2;hb=HEAD;hp=37f8a2c0448de17eb35174090fdae01393cdbcec;hpb=5101a793944fe2285cd5077897bc15c3f1681349;p=rrq%2Ffusefile.git

diff --git a/fusefile.c b/fusefile.c
index 37f8a2c..a1bf2bd 100644
--- a/fusefile.c
+++ b/fusefile.c
@@ -41,6 +41,8 @@ struct Region {
     off_t end;
 };
 
+#define REGIONKEEP(r) ((r,beg == r.end)?: 0 : 1)
+
 struct Source {
     char *filename;
     ssize_t from;
@@ -50,6 +52,8 @@ struct Source {
     int dirty;
 };
 
+#define ENDSOURCE( S ) ( S.start + ( S.to - S.from ) )
+
 static struct {
     struct Source *array;
     int count;
@@ -65,12 +69,12 @@ static struct {
 /**
  * Overlay
  */
-static struct {
+static struct Overlay {
     struct Source source;
     struct Region *table;
     size_t count;
     size_t limit;
-} overlay;
+} overlay; // The current overlay.
 
 static void usage();
 
@@ -270,13 +274,25 @@ static void overlay_mark(off_t beg,off_t end) {
 #endif
 }
 
-static void setup_overlay(char *filename) {
-    overlay.source.filename = filename;
-    overlay.source.fd = open( filename, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR );
-    if ( overlay.source.fd < 0 ) {
-	perror( filename );
+/**
+ * Capture overlay filenames for processing after source fragments.
+ */
+static void overlay_setup(char *filenames) {
+    overlay.source.filename = filenames;
+}
+
+// Duplicate the source record data at the given index.
+static void dup_source_item(int index) {
+    sources.count++;
+    sources.array = realloc(
+	sources.array, sources.count * sizeof( struct Source ) );
+    if ( sources.array == 0 ) {
+	fprintf( stderr, "** OOM when expanding frament table\n" );
 	usage();
     }
+    // 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
@@ -313,7 +329,7 @@ static int setup_source(struct Source *p,char *frag) {
 	perror( p->filename );
 	return 1; // Error return
     }
-    if ( ( range == 0 ) && stat( p->filename, &filestat ) ) {
+    if ( ( range != 0 ) && stat( p->filename, &filestat ) ) {
 	perror( p->filename );
 	return 1; 
     }
@@ -447,28 +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;
 }
 
@@ -507,30 +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;
@@ -541,20 +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 );
@@ -626,6 +616,145 @@ static void overlay_load() {
     }
 }
 
+/**
+ * Inject an overlay fragment into the source table, end return the
+ * end of the injected fragment.
+ */
+static off_t overlay_inject_from_region(off_t beg,off_t end) {
+    int index = find_source( beg );
+    if ( index < 0 ) {
+	fprintf( stderr, "** Injecting %s at %ld failed\n",
+		 overlay.source.filename, beg );
+	usage();
+    }
+    if ( end > ENDSOURCE( sources.array[ index ] ) ) {
+	end = ENDSOURCE( sources.array[ index ] );
+    }
+    struct Region frags[3] = {
+	{ sources.array[ index ].start, beg },
+	{ 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 ) {
+	// Handle any portion before injection point.
+	dup_source_item( index );
+	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 = 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 += frags[1].end - frags[1].beg;
+#if DEBUG
+	fprintf( stderr, "item %d ", index+1 );
+	print_source( &sources.array[ index+1 ] );
+#endif
+    }
+    // Set up the injection fragment
+    sources.array[ index ].filename = overlay.source.filename;
+    sources.array[ index ].from = beg;
+    sources.array[ index ].to = end;
+    sources.array[ index ].fd = overlay.source.fd;
+#if DEBUG
+	fprintf( stderr, "item %d ", index );
+	print_source( &sources.array[ index ] );
+#endif
+    return end;
+}
+
+/**
+ * Inject the current (unopened) overlay into the source list.
+ */
+static void overlay_inject() {
+    overlay.source.fd = open( overlay.source.filename, O_RDONLY );
+    if ( overlay.source.fd < 0 ) {
+	perror( overlay.source.filename );
+	usage();
+    }
+    
+    if ( lseek( overlay.source.fd, overlay.source.to, SEEK_SET ) < 0 ) {
+	perror( overlay.source.filename );
+	usage();
+    }
+    size_t count = 0;
+    size_t size = sizeof( overlay.count );
+    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 );
+	return;
+    }
+    size = count * sizeof( struct Region );
+    overlay.table = calloc( sizeof( struct Region ), count );
+    if ( read( overlay.source.fd, overlay.table, size ) != size ) {
+	fprintf( stderr, "** error injecting %s\n", overlay.source.filename );
+	usage();
+    }
+    size_t i;
+    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;
+}
+
+/**
+ * Each stacked overlay file is nested into to source list
+ */
+static void overlay_post_setup() {
+    char *end;
+    while ( ( end = strchr( overlay.source.filename, ':' ) ) ) {
+	*end = 0; //
+	overlay_inject();
+	overlay.source.filename = end + 1;
+    }
+    if ( *overlay.source.filename ) {
+	overlay.source.fd = open( overlay.source.filename,
+				  O_RDWR | O_CREAT, S_IRUSR | S_IWUSR );
+	if ( overlay.source.fd < 0 ) {
+	    perror( overlay.source.filename );
+	    usage();
+	}
+	overlay_load();
+    }
+}
+
 /**
  * Write a full block of data over the sources at the offset
  */
@@ -676,7 +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++ ) {
@@ -717,6 +845,40 @@ 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
@@ -799,12 +961,10 @@ void *fusefile_init(struct fuse_conn_info *fci) {
     return 0;
 }
 
-#define ENDSOURCE( S ) ( S.start + ( S.to - S.from ) )
-
 /**
  * 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 +974,37 @@ 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 ].from,
+			 sources.array[ src ].to );
+	    }
 	    pos = ENDSOURCE( sources.array[ src ] );
 	}
-	if ( sources.array[ src ].start < x ) {
+	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,
+			 sources.array[ src ].from +
+			 pos - sources.array[ src ].start,
+			 x - sources.array[ src ].start +
+			 sources.array[ src ].from
+			 );
+	    }
 	    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 &&
@@ -881,6 +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* ) )
@@ -926,11 +1099,10 @@ int main(int argc, char *argv[])
     }
     fuseargc = i;
     mnt = argv[ i++ ]; // First non-option argument is the mount pount
-    char *overlaytag = "-overlay:";
-    int overlaytagsize = strlen( overlaytag );
-    if ( strncmp( argv[i], overlaytag, overlaytagsize ) == 0 ) {
-	// consume "-overlay:filename"
-	setup_overlay( argv[i++] + overlaytagsize ); // Need a writable file
+    #define OVERLAYTAG "-overlay:"
+    if ( strncmp( argv[i], OVERLAYTAG, strlen( OVERLAYTAG ) ) == 0 ) {
+	// consume "-overlay:filename[,filename]*"
+	overlay_setup( argv[i++] + strlen( OVERLAYTAG ) );
 	if ( i >= argc ) {
 	    usage();
 	}
@@ -940,7 +1112,7 @@ int main(int argc, char *argv[])
     }
     if ( overlay.source.filename ) {
 	overlay.source.to = sources.size; // Register total size.
-	overlay_load();
+	overlay_post_setup();
     }
     if ( stat( mnt, &stbuf ) == -1 ) {
 	int fd = open( mnt, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR );
@@ -975,7 +1147,10 @@ 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 ) ) {