X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;f=fusefile.c;h=59dcaa5fb746b13f90098c69c7e278b21b73490e;hb=a56b1315a88e0c89573e99a22e7ae6353f845760;hp=476ca9d8fb1ffa847e094150b44223a816ed7603;hpb=d7e225ba17002eec13f528e33fe4fc7c54788388;p=rrq%2Ffusefile.git

diff --git a/fusefile.c b/fusefile.c
index 476ca9d..59dcaa5 100644
--- a/fusefile.c
+++ b/fusefile.c
@@ -61,49 +61,10 @@ static void print_source(struct Source *p) {
 }
 #endif
 
-// Scan the source specification, and return the length of the
-// inclusion. "filename/from,to"
-// filename
-// filename/from
-// filename/-to
-// filename/from-to
-static size_t scan_source(char *in,struct Source *p) {
-    int e = strlen( in );
-    int i = e-1;
-    int s = -1;
-    int m = -1;
-    // scan for last '/' and last '-'
-    for ( ; i >= 0; i-- ) {
-	if ( in[i] == '/' ) {
-	    s = i;
-	    break;
-	}
-	if ( in[i] == '-' ) {
-	    m = i;
-	}
-    }
-#if DEBUG
-    fprintf( stderr, "m=%d s=%d\n", m, s );
-#endif
-    // Copy the filename, and set from and to
-    p->filename = strndup( in, ( s < 0 )? e : s );
-    struct stat buf;
-    if ( stat( p->filename, & buf ) ) {
-	perror( p->filename );
-	return 1; 
-    }
-    p->from = ( s < 0 )? 0 : atol( in+s+1 );
-    if ( p->from < 0 ) {
-	p->from = 0;
-    }
-#if DEBUG
-    fprintf( stderr, "p->from=%ld\n", p->from );
-#endif
-    p->to = ( m < 0 )? buf.st_size : atol( in+m+1 );
-    if ( p->from > p->to || p->to > buf.st_size ) {
-	return 1;
-    }
-    return 0;
+static char *range;
+static unsigned int c;
+static int RANGE(int s,int n ) {
+    return ( s == n ) && *(range+c) == 0;
 }
 
 static int setup_sources(char **argv,int i,int n) {
@@ -115,22 +76,75 @@ static int setup_sources(char **argv,int i,int n) {
     int j = 0;
     sources.size = 0;
     for ( ; j < n; i++, j++ ) {
+	struct stat filestat;
 	struct Source *p = sources.array + j;
-	if ( scan_source( argv[i], p ) ) {
-	    // should free everything malloc-ed
-	    return 1;
-	}
-	p->start = sources.size;
-	sources.size += p->to - p->from;
+	// Open the fragment file rw if possible, else ro
+	range = strrchr( argv[i], '/' ); // last '/'
+	p->filename = range? strndup( argv[i], range - argv[i] ) : argv[i];
 	p->fd = open( p->filename, O_RDWR );
+	int rdonly = 0;
 	if ( p->fd < 0 ) {
-	    fprintf( stderr, "** %s opened read-only\n", p->filename );
+	    rdonly = 1;
 	    p->fd = open( p->filename, O_RDONLY );
 	}
 	if ( p->fd < 0 ) {
 	    perror( p->filename );
+	    return 1; // Error return
+	}
+	if ( stat( p->filename, &filestat ) ) {
+	    perror( p->filename );
+	    return 1; 
+	}
+	if ( rdonly ) {
+	    fprintf( stderr, "** %s opened read-only\n", p->filename );
+	}
+	p->from = 0;
+	p->to = filestat.st_size;
+	// Process any range variation
+	if ( range && *(++range) ) {
+	    int a,b;
+	    if ( 0 ) {
+	    } else if ( RANGE( sscanf( range, "%d:%d%n", &a, &b, &c ), 2 )) {
+		p->from = ( a < 0 )? ( p->to + a ) : a;
+		p->to = ( b < 0 )? ( p->to + b ) : b;
+	    } else if ( RANGE( sscanf( range, "%d+%d%n", &a, &b, &c ), 2 )) {
+		p->from = ( a < 0 )? ( p->to + a ) : a;
+		p->to = ( ( b < 0 )? p->to : p->from ) + b;
+	    } else if ( RANGE( sscanf( range, "%d+%n", &a, &c ), 1 )) {
+		p->from = ( a < 0 )? ( p->to + a ) : a;
+	    } else if ( RANGE( sscanf( range, ":%d%n", &b, &c ), 1 )) {
+		p->to = ( b < 0 )? ( p->to + b ) : b;
+	    } else if ( RANGE( sscanf( range, "%d:%n", &a, &c ), 1 )) {
+		p->from = ( a < 0 )? ( p->to + a ) : a;
+	    } else if ( RANGE( sscanf( range, "%d%n", &a, &c ), 1 )) {
+		if ( a >= 0 ) {
+		    p->from = a;
+		} else {
+		    p->from = p->to + a;
+		}
+	    } else if ( RANGE( sscanf( range, ":%n", &c), 0 ) ) {
+		// to end from start
+	    } else {
+		fprintf( stderr, "** BAD RANGE: %s\n", argv[i] );
+		return 1;
+	    }
+	}
+	if ( ( filestat.st_mode &  S_IFMT ) == S_IFCHR ) {
+	    filestat.st_size = p->to; // Pretend size of character device
+	}
+	if ( p->from < 0 ) {
+	    p->from = 0;
+	}
+	if ( p->to > filestat.st_size ) {
+	    p->to = filestat.st_size;
+	}
+	if ( p->from >= p->to || p->from >= filestat.st_size ) {
+	    fprintf( stderr, "** BAD RANGE: %s [%ld:%ld]\n",
+		     argv[i], p->from, p->to );
 	    return 1;
 	}
+	p->start = sources.size; // the fusefile position of fragment
+	sources.size += p->to - p->from;
 #if DEBUG
 	print_source( p );
 #endif
@@ -186,14 +200,28 @@ 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;
 }
 
@@ -210,14 +238,14 @@ static int fusefile_read(const char *path, char *buf, size_t size,
 #if DEBUG
     fprintf( stderr, "read %ld %ld\n", off, size );
 #endif
-    size_t rr = 0;
+    size_t rr = 0; // total reading
     while ( size > 0 ) {
 #if DEBUG
-	fprintf( stderr, "find_source %ld %ld\n", off, size );
+	fprintf( stderr, "  find_source %ld %ld\n", off, size );
 #endif
 	int i = find_source( off );
 	if ( i < 0 ) {
-	    return ( off == sources.size )? 0 : -ENOENT;
+	    return ( off == sources.size )? rr : -ENOENT;
 	}
 	if ( sources.array[i].fd < 0 ) {
 	    return -ENOENT;
@@ -225,21 +253,26 @@ static int fusefile_read(const char *path, char *buf, size_t size,
 #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;
 	if ( n > size ) {
 	    n = size;
 	}
+#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, "get %ld bytes at %ld\n", n, rr );
+	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\n", r );
 #endif
 	if ( r < 0 ) {
 	    perror( sources.array[i].filename );
@@ -252,10 +285,31 @@ static int fusefile_read(const char *path, char *buf, size_t size,
 	off += r;
 	size -= r;
     }
-    times.atime = time( 0 );
+#if DEBUG
+    fprintf( stderr, "  total reading %ld bytes\n", rr );
+#endif
     return rr;
 }
 
+/**
+ * Poll for IO readiness.
+ */
+int fusefile_poll(const char *path, struct fuse_file_info *fi,
+		   struct fuse_pollhandle *ph, unsigned *reventsp )
+{
+#if DEBUG
+    fprintf( stderr, "fusefile_poll( %s ) %p %d\n", path, ph, *reventsp );
+#endif
+    if( strcmp( path, "/" ) != 0 ) {
+	return -ENOENT;
+    }
+    if ( ph ) {
+	return fuse_notify_poll( ph );
+    }
+    return 0;
+}
+
+
 /**
  * Write a full block of data over the sources at the offset
  */
@@ -269,8 +323,8 @@ static int write_block(off_t off,const char *buf,size_t size) {
 	    return -EIO; // past EOF
 	}
 	struct Source *source = &sources.array[ index ];
-	off_t from = off - source->start;
-	off_t max = source->to - source->from - from;
+	off_t from = off - source->start + source->from;
+	off_t max = source->to - from;
 	if ( lseek( source->fd, from, SEEK_SET ) < 0 ) {
 	    return -EIO;
 	}
@@ -392,11 +446,25 @@ static int fusefile_truncate(const char *path, off_t len) {
     return -EIO;
 }
 
+void *fusefile_init(struct fuse_conn_info *fci) {
+#if DEBUG
+    fprintf( stderr, "fusefile_init( %d, %d )\n", fci->async_read, fci->want );
+#endif
+    // Disable asynchronous reading
+    fci->async_read = 0;
+    fci->want &= ~FUSE_CAP_ASYNC_READ;
+#if DEBUG
+    fprintf( stderr, "fusefile_init( %d, %d )\n", fci->async_read, fci->want );
+#endif
+    return 0;
+}
+
 static struct fuse_operations fusefile_oper = {
     .getattr = fusefile_getattr,
     .chmod = fusefile_chmod,
     .open = fusefile_open,
     .read = fusefile_read,
+    .poll = fusefile_poll,
     .write = fusefile_write,
     .write_buf = fusefile_write_buf,
     .destroy = fusefile_destroy,
@@ -406,13 +474,13 @@ static struct fuse_operations fusefile_oper = {
     .truncate = fusefile_truncate,
     //.truncate = fusefile_truncate,
     //.release = fusefile_release,
-    //void *(*init) (struct fuse_conn_info *conn);
+    .init = fusefile_init,
 };
 
 static void usage() {
     char *usage =
 "Usage: fusefile [ <fuse options> ] <mount> <file/from-to> ... \n"
-"Mounts a virtual, read-only file that is a concatenation of file fragments\n"
+"Mounts a virtual, file that is a concatenation of file fragments\n"
 	;
     fprintf( stderr, "%s", usage );
     exit( 1 );
@@ -420,28 +488,31 @@ static void usage() {
 
 /**
  * Set up the arguments for the fuse_main call, adding our own.
+ * argv[argc] is the mount point argument
  */
 static int setup_argv(int argc,char ***argv) {
+    // note: (*argv)[ argc ] is the mount point argument
     char *OURS[] = {
 	"-odefault_permissions",
-	(*argv)[ --argc ]  // note: (*argv)[ argc-1 ] = the mount point
+	(*argv)[ argc ]
     };
 #define OURSN ( sizeof( OURS ) / sizeof( char* ) )
-    int N = argc + OURSN; // new argv-tobe size, excluding null
-    char **out = malloc( ( N + 1 ) * sizeof( char* ) );
+    int N = argc + OURSN;
+    // Allocate new arg array plus terminating null pointer
+    char **out = malloc( ( N + 1 ) * sizeof( char* ) ); 
     int i;
     for ( i = 0; i < argc; i++ ) {
 	out[ i ] = (*argv)[i];
-	fprintf( stderr, " %s", out[ i ] );
+	//fprintf( stderr, " %s", out[ i ] );
     }
     for ( i = 0; i < OURSN; i++ ) {
 	out[ argc + i ] = OURS[i];
-	fprintf( stderr, " %s", out[ i ] );
+	//fprintf( stderr, " %s", out[ i ] );
     }
     out[ N ] = 0;
-    fprintf( stderr, "\n" );
+    //fprintf( stderr, "\n" );
     (*argv) = out;
-    return N;
+    return N; // Don't include the terminating null pointer
 }
 
 /**
@@ -466,8 +537,8 @@ int main(int argc, char *argv[])
     if ( i > argc - 2 ) { // At least mount point plus one source
 	usage();
     }
-    mnt = argv[ i++ ]; // First non-option argument is the mount pount
     fuseargc = i;
+    mnt = argv[ i++ ]; // First non-option argument is the mount pount
     if ( setup_sources( argv, i, argc-i ) ) {
 	return 1;
     }
@@ -492,6 +563,16 @@ int main(int argc, char *argv[])
 	times.ctime = stbuf.st_ctime;
     }
 
+    {
+	int fd = open( mnt, O_RDWR, S_IRUSR | S_IWUSR );
+	if ( fd < 0 ) {
+	    perror( mnt );
+	    return 1;
+	}
+	if ( lseek( fd, sources.size, SEEK_SET ) < 0 ) {
+	    return -EIO;
+	}
+    }
     fuseargc = setup_argv( fuseargc, &argv );
     struct fuse_args args = FUSE_ARGS_INIT( fuseargc, argv );
     if ( fuse_parse_cmdline( &args, &mnt, &mt, &fg ) ) {