Full sparsebundle implementation

BasiliskII/src/Unix/disk_sparsebundle.cpp

@@ -19,13 +19,15 @@
  */
 
 #include "disk_unix.h"
+#include "tinyxml2.h"
 
 #include <limits.h>
  
 // TODO
-// - Factory needs to actually check stuff
 // - Add to basilisk build
 // - Add to 'make links'
+// - Test on Linux
+// - Iterate through factories 
 
 typedef ssize_t (band_func)(int fd, void *buf, size_t len);
 
@@ -132,23 +134,131 @@ protected:
 	}
 };
 
+
+
+using tinyxml2::XML_NO_ERROR;
+using tinyxml2::XMLElement;
+
+// Simplistic plist parser
+struct plist {
+	plist() : doc(true, tinyxml2::COLLAPSE_WHITESPACE) { }
+	
+	bool open(const char *path) {
+		if (doc.LoadFile(path) != XML_NO_ERROR)
+			return false;
+		tinyxml2::XMLHandle hnd(&doc);
+		dict = hnd.FirstChildElement("plist").FirstChildElement("dict")
+			.ToElement();
+		return dict;
+	}
+	
+	const char *str_val(const char *key) {
+		return value(key, "string");
+	}
+
+	bool int_val(const char *key, loff_t *i) {
+		const char *v = value(key, "integer");
+		if (!v || !*v)
+			return false;
+		
+		char *endp;
+		long long ll = strtoll(v, &endp, 10);
+		if (*endp)
+			return false;
+		*i = ll;
+		return true;
+	}
+	
+protected:
+	tinyxml2::XMLDocument doc;
+	XMLElement *dict;
+	
+	const char *value(const char *key, const char *type) {
+		// Assume it's a flat plist
+		XMLElement *cur = dict->FirstChildElement();
+		bool found_key = false;
+		while (cur) {
+			if (found_key) {
+				if (strcmp(cur->Name(), type) != 0)
+					return NULL;
+				return cur->GetText();
+			}
+			found_key = strcmp(cur->Name(), "key") == 0
+				&& strcmp(cur->GetText(), key) == 0;
+			cur = cur->NextSiblingElement();
+		}
+		return NULL;
+	}
+};
+
+
+static int try_open(const char *path, bool read_only) {
+	int oflags = (read_only ? O_RDONLY : O_RDWR);
+#if defined(__MACOSX__)
+	oflags |= O_EXLOCK;
+#endif
+	int fd = open(path, oflags);
+#if defined(__MACOSX__)
+	if (fd == -1) {
+		if (errno == EOPNOTSUPP) { // no locking support
+			oflags &= ~O_EXLOCK;
+			fd = open(path, oflags);
+		} else if (errno == EAGAIN) { // already locked
+			fprintf(stderr, "sparsebundle: Refusing to double-mount\n");
+		}
+	}
+#endif
+	return fd;
+}
+
 disk_generic *disk_sparsebundle_factory(const char *path, bool read_only) {
-	if (strstr(path, ".sparsebundle") == NULL)
-		return NULL; // FIXME: real test
-	
-	// FIXME: actually read these
-	loff_t band_size = 1048576;
-	loff_t total_size = 53687091200;
-	
-	// FIXME: check for double-mount, writable
-	int token = 0;
-	read_only = false;
-	
+	// Does it look like a sparsebundle?
 	char buf[PATH_MAX + 1];
+	if (snprintf(buf, PATH_MAX, "%s/%s", path, "Info.plist") >= PATH_MAX)
+		return NULL;
+	
+	plist pl;
+	if (!pl.open(buf))
+		return NULL;	
+	
+	const char *type;
+	if (!(type = pl.str_val("diskimage-bundle-type")))
+		return NULL;
+	if (strcmp(type, "com.apple.diskimage.sparsebundle") != 0)
+		return NULL;
+	
+	
+	// Find the sparsebundle parameters
+	loff_t version, band_size, total_size;
+	if (!pl.int_val("bundle-backingstore-version", &version) || version != 1) {
+		fprintf(stderr, "sparsebundle: Bad version\n");
+		return NULL;
+	}
+	if (!pl.int_val("band-size", &band_size)
+			|| !pl.int_val("size", &total_size)) {
+		fprintf(stderr, "sparsebundle: Can't find size\n");
+		return NULL;
+	}
+	
+	
+	// Check if we can open it
+	if (snprintf(buf, PATH_MAX, "%s/%s", path, "token") >= PATH_MAX)
+		return NULL;
+	int token = try_open(buf, read_only);
+	if (token == -1 && !read_only) { // try again, read-only
+		read_only = true;
+		token = try_open(buf, read_only);
+	}
+	if (token == -1) {
+		fprintf(stderr, "sparsebundle: Can't open the bundle\n");
+		return NULL;
+	}
+	
+	
+	// We're good to go!
 	if (snprintf(buf, PATH_MAX, "%s/%s", path, "bands") >= PATH_MAX)
 		return NULL;
 	char *bands = strdup(buf);
-	
 	return new disk_sparsebundle(bands, token, read_only, band_size,
 		total_size);
 }

SheepShaver/src/Unix/Makefile.in

@@ -59,7 +59,7 @@ SRCS = ../main.cpp main_unix.cpp ../prefs.cpp ../prefs_items.cpp prefs_unix.cpp
     ../macos_util.cpp ../timer.cpp timer_unix.cpp ../xpram.cpp xpram_unix.cpp \
     ../adb.cpp ../sony.cpp ../disk.cpp ../cdrom.cpp ../scsi.cpp \
     ../gfxaccel.cpp ../video.cpp video_blit.cpp ../audio.cpp ../ether.cpp ../thunks.cpp \
-    ../serial.cpp ../extfs.cpp disk_sparsebundle.cpp \
+    ../serial.cpp ../extfs.cpp disk_sparsebundle.cpp tinyxml2.cpp \
     about_window_unix.cpp ../user_strings.cpp user_strings_unix.cpp \
     vm_alloc.cpp sigsegv.cpp rpc_unix.cpp \
     sshpty.c strlcpy.c $(SYSSRCS) $(CPUSRCS) $(MONSRCS) $(SLIRP_SRCS)