X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;f=fusefile.c;h=59dcaa5fb746b13f90098c69c7e278b21b73490e;hb=f2a64b0bd6a5624ec37ec31a07747bfb063a7bb6;hp=41c6ed6042f6ca9462b02f19b45f6136a8eb0ae3;hpb=26b59ee2e0ee0a47f19153e629ce0c7a94bb134d;p=rrq%2Ffusefile.git

diff --git a/fusefile.c b/fusefile.c
index 41c6ed6..59dcaa5 100644
--- a/fusefile.c
+++ b/fusefile.c
@@ -45,70 +45,26 @@ struct Source {
 static struct {
     struct Source *array;
     int count;
-    int limit;
     ssize_t size;
 } sources;
 
-#define SOURCEARRAYP(i) ((void*)&sources.array[ i ])
-
-/**
- * Holds info about scratch pad file for 'write' events.
- */
 static struct {
-    char *filename;
-    int fd;
-} pad;
-
+    time_t atime;
+    time_t mtime;
+    time_t ctime;
+} times;
+    
 #if DEBUG
 static void print_source(struct Source *p) {
     fprintf( stderr, "%p { %s, %ld, %ld, %ld, %d }\n",
-	     p, p->filename, p->from, p->to, p->start, p->fd );
+	     p, p->filename, p->from, p->to, p->start, p-> fd );
 }
 #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) {
@@ -117,22 +73,78 @@ static int setup_sources(char **argv,int i,int n) {
 	return 1;
     }
     sources.count = n;
-    sources.limit = 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;
+	// 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 ) {
+	    rdonly = 1;
+	    p->fd = open( p->filename, O_RDONLY );
 	}
-	p->start = sources.size;
-	sources.size += p->to - p->from;
-	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
@@ -151,21 +163,24 @@ static int fusefile_getattr(const char *path,struct stat *stbuf) {
     fprintf( stderr, "getattr %ld\n", sources.size );
 #endif
     memset( stbuf, 0, sizeof( struct stat ) );
-    stbuf->st_mode = S_IFREG | 0444; // Hmmm
-    if ( pad.filename ) {
-	stbuf->st_mode |= 0200;
-    }
+    stbuf->st_mode = S_IFREG | 0644; // Hmmm
     stbuf->st_nlink = 1;
     stbuf->st_size = sources.size;
-    time_t now = time( 0 );
-    stbuf->st_atime = now;
-    stbuf->st_mtime = now;
-    stbuf->st_ctime = now;
+    stbuf->st_atime = times.atime;
+    stbuf->st_mtime = times.mtime;
+    stbuf->st_ctime = times.ctime;
     stbuf->st_uid = getuid();
     stbuf->st_gid = getgid();
     return 0;
 }
 
+static int fusefile_chmod(const char *path,mode_t m) {
+#if DEBUG
+    fprintf( stderr, "fusefile_chmod( %s, %d )\n", path, m );
+#endif
+    return -1;
+}
+
 static int fusefile_open(const char *path,struct fuse_file_info *fi) {
 #if DEBUG
     fprintf( stderr, "fusefile_open( %s, %d )\n", path, fi->flags );
@@ -175,98 +190,62 @@ static int fusefile_open(const char *path,struct fuse_file_info *fi) {
 	return -ENOENT;
     }
     // set O-CLOEXEC  for this opening?
+    times.atime = time( 0 );
     return 0;
 }
 
 static int find_source(off_t offset) {
     int lo = 0;
     int hi = sources.count;
-    if ( offset > sources.size ) {
+    if ( offset >= sources.size ) {
 	return -1;
     }
-    while ( lo < hi ) {
+#if DEBUG
+    fprintf( stderr, "find_source( %ld )\n", offset );
+#endif
+    while ( lo + 1 < hi ) {
 	int m = ( lo + hi ) / 2;
-	if ( sources.array[m].start > offset ) {
+	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 ( m+1 < hi && sources.array[m+1].start < offset ) {
-	    lo = m+1;
 	} else {
-	    return m;
+#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;
 }
 
-/**
- * Insert a source fragment description into the table at <off>.
- */
-static int insert_source(struct Source *source,size_t off) {
-    int index = find_source( off );
-    // Ensure at least 5 "free" Sources in <source.array>
-    // and allocate space for 20 new otherwise.
-    if ( sources.count + 5 > sources.limit ) {
-	size_t size = sources.limit + 20;
-	struct Source *new = realloc(
-	    sources.array, size * sizeof( struct Source ) );
-	if ( new == 0 ) {
-	    return -1;
-	}
-	sources.array = new;
-	sources.limit = size;
-    }
-    if ( index < sources.count ) {
-	ssize_t b = ( sources.count - index ) * sizeof(struct Source);
-	if ( sources.array[ index ].start < off ) {
-	    // Split the <index> record at <off>
-	    // and adjust index
-	    b *= 2;
-	    memcpy( SOURCEARRAYP( index+2 ), SOURCEARRAYP( index ), b );
-	    sources.count += 2;
-	    b = off - sources.array[ index ].start;
-	    sources.array[ index + 2 ].from += b; // adjust tail fragment
-	    sources.array[ index++ ].to = b; // adjust head fragment
-	} else {
-	    // Insert the new source at <index>
-	    memcpy( SOURCEARRAYP( index+1 ), SOURCEARRAYP( index ), b );
-	    sources.count += 1;
-	}
-    } else {
-	// Append the new source to <sources> (at <index>)
-	sources.count += 1;
-    }
-    sources.array[ index ].filename = source->filename;
-    sources.array[ index ].fd = source->fd;
-    sources.array[ index ].from = source->from;
-    sources.array[ index ].to = source->to;
-    for ( ; index < sources.count; index++ ) {
-	sources.array[ index ].start = off;
-	off += sources.array[ index ].to - sources.array[ index ].from;
-    }
-    sources.size = off;
-    return index;
-}
-
-// Read <size> bytes from <off> in file
+// Read <size> bytes from <offset> in file
 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 ) {
+    if( strcmp( path, "/" ) != 0 ) {
 	return -ENOENT;
     }
 #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 -ENOENT;
+	    return ( off == sources.size )? rr : -ENOENT;
 	}
 	if ( sources.array[i].fd < 0 ) {
 	    return -ENOENT;
@@ -274,21 +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 );
@@ -301,64 +285,111 @@ static int fusefile_read(const char *path, char *buf, size_t size,
 	off += r;
 	size -= r;
     }
+#if DEBUG
+    fprintf( stderr, "  total reading %ld bytes\n", rr );
+#endif
     return rr;
 }
 
 /**
- * Write a full block of data.
+ * 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
  */
-static int write_block(int fd,const char *buf,size_t size) {
-    size_t orig = size;
+static int write_block(off_t off,const char *buf,size_t size) {
+#if DEBUG
+    fprintf( stderr, "write_block( %ld, ?, %ld )\n", off, size );
+#endif
     while ( size > 0 ) {
-	ssize_t n = write( fd, buf, size );
-	if ( n <= 0 ) {
-	    return n;
+	int index = find_source( off ); // index of source file
+	if ( index < 0 ) {
+	    return -EIO; // past EOF
+	}
+	struct Source *source = &sources.array[ index ];
+	off_t from = off - source->start + source->from;
+	off_t max = source->to - from;
+	if ( lseek( source->fd, from, SEEK_SET ) < 0 ) {
+	    return -EIO;
+	}
+	ssize_t todo = ( size < max )? size : max;
+	while ( todo > 0 ) {
+	    times.mtime = time( 0 );
+	    ssize_t n = write( source->fd, buf, todo );
+	    if ( n <= 0 ) {
+		return -EIO; // Something wrong
+	    }
+	    buf += n;
+	    todo -= n;
+	    size -= n;
+	    off += n;
 	}
     }
-    return orig;
+    return 0;
+}
+
+static int fusefile_write_buf(const char *path, struct fuse_bufvec *buf,
+			      off_t off, struct fuse_file_info *fi) {
+#if DEBUG
+    fprintf( stderr, "fusefile_write_buf( %s )\n", path );
+#endif
+    if ( strcmp( path, "/" ) != 0 ) {
+	return -ENOENT;
+    }
+
+    size_t size = 0;
+    int i;
+    for ( i = 0; i < buf->count; i++ ) {
+	struct fuse_buf *p = &buf->buf[i];
+	if ( p->flags & FUSE_BUF_IS_FD ) {
+#if DEBUG
+	    fprintf( stderr, "Content held in a file ... HELP!!\n" );
+#endif
+	    return -EIO;
+	}
+	if ( write_block( off, (char*) p->mem, p->size ) < 0 ) {
+	    return -EIO;
+	}
+	size += p->size;
+    }
+#if DEBUG
+    fprintf( stderr, "fusefile_write_buf written %ld\n", size );
+#endif
+    return size;
 }
 
 /**
- * Insert a fragment at <off>. The data is appended to the pad file,
- * and a descriptor is inserted; the fragment containing <off> is
- * first split, unless <off> is at its start, and then new fragment
- * descriptor is inserted.
+ * Write a fragment at <off>. This overwrites files.
  */
 static int fusefile_write(const char *path, const char *buf, size_t size,
 			  off_t off, struct fuse_file_info *fi)
 {
 #if DEBUG
-    fprintf( stderr, "fusefile_write( %s )\n", path );
+    fprintf( stderr, "fusefile_write( %s %ld )\n", path, size );
 #endif
     if ( strcmp( path, "/" ) != 0 ) {
 	return -ENOENT;
     }
-#if DEBUG
-    fprintf( stderr, "write %ld %ld\n", off, size );
-#endif
-    // Ensure a pad was nominated
-    if ( pad.filename == 0 ) {
-	return 1;
-    }
-    static char meta[ 100 ];
-    sprintf( meta, "%ld\n%ld\n", off, size );
-    if ( write_block( pad.fd, meta, strlen( meta ) ) <= 0 ) {
-	perror( pad.filename );
+
+    if ( write_block( off, buf, size ) < 0 ) {
 	return -EIO;
     }
-    struct Source source = {
-	.filename = pad.filename,
-	.fd = pad.fd,
-	.from = lseek( pad.fd, 0, SEEK_END ),
-	.to = 0,
-	.start = 0
-    };
-    ssize_t n = write_block( pad.fd, buf, size );
-    if ( n != size ) {
-	return n;
-    }
-    source.to = source.from + size;
-    insert_source( &source, off );
     return size;
 }
 
@@ -402,27 +433,54 @@ static int fusefile_fsync(const char *path, int x, struct fuse_file_info *fi) {
     return 0;
 }
 
+/**
+ * 
+ */
+static int fusefile_truncate(const char *path, off_t len) {
+#if DEBUG
+    fprintf( stderr, "fusefile_truncate( %s, %ld )\n", path, len );
+#endif
+    if ( strcmp( path, "/" ) != 0 ) {
+	return -ENOENT;
+    }
+    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,
     .flush = fusefile_flush,
     .release = fusefile_release,
     .fsync = fusefile_fsync,
-    //void *(*init) (struct fuse_conn_info *conn);
-    //int (*write_buf) (const char *, struct fuse_bufvec *buf, off_t off,
-    //		  struct fuse_file_info *);
+    .truncate = fusefile_truncate,
     //.truncate = fusefile_truncate,
-    //.flush = fusefile_flush,
     //.release = fusefile_release,
+    .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 );
@@ -430,15 +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) {
-    int n = argc + 1;
-    char **out = calloc( n--, sizeof( char* ) );
-    memcpy( (void*) out, (void*) (*argv), argc-- * sizeof( char* ) ); 
-    out[ n++ ] = out[ argc ]; // mount point
-    out[ argc++ ] = "-odefault_permissions";
+    // note: (*argv)[ argc ] is the mount point argument
+    char *OURS[] = {
+	"-odefault_permissions",
+	(*argv)[ argc ]
+    };
+#define OURSN ( sizeof( OURS ) / 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 ] );
+    }
+    for ( i = 0; i < OURSN; i++ ) {
+	out[ argc + i ] = OURS[i];
+	//fprintf( stderr, " %s", out[ i ] );
+    }
+    out[ N ] = 0;
+    //fprintf( stderr, "\n" );
     (*argv) = out;
-    return n;
+    return N; // Don't include the terminating null pointer
 }
 
 /**
@@ -463,21 +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;
-    if ( strncmp( argv[ i ], "pad=", 4 ) == 0 ) {
-	// First argument is the pad, if any, signaled with "pad=" prefix
-	pad.filename = argv[ i++ ] + 4; // (also move arg index)
-#if DEBUG
-	fprintf( stderr, "scratch pad=%s\n", pad.filename );
-#endif
-	pad.fd = open( pad.filename, O_RDWR | O_CREAT, 0600 );
-	if ( pad.fd < 0 ) {
-	    perror( pad.filename );
-	    exit( errno );
-	}
-	lseek( pad.fd, 0, SEEK_END ); // initial seek
-    }
+    mnt = argv[ i++ ]; // First non-option argument is the mount pount
     if ( setup_sources( argv, i, argc-i ) ) {
 	return 1;
     }
@@ -487,11 +548,30 @@ int main(int argc, char *argv[])
 	    perror( mnt );
 	    return 1;
 	}
+	time_t now = time( 0 );
+	times.atime = now;
+	times.mtime = now;
+	times.ctime = now;
 	temporary = 1;
 	close( fd );
     } else if ( ! S_ISREG( stbuf.st_mode ) ) {
 	fprintf( stderr, "mountpoint is not a regular file\n" );
 	return 1;
+    } else {
+	times.atime = stbuf.st_atime;
+	times.mtime = stbuf.st_mtime;
+	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 );