1 files changed, 114 insertions, 49 deletions

diff --git a/libfdisk/src/context.c b/libfdisk/src/context.c
index 56ebb6c1e..f97f0a612 100644
--- a/libfdisk/src/context.c
+++ b/libfdisk/src/context.c
@@ -17,13 +17,13 @@
  *
  * The library distinguish between three types of partitioning objects.
  *
- * on-disk data
+ * on-disk label data
  *    - disk label specific
  *    - probed and read  by disklabel drivers when assign device to the context
  *      or when switch to another disk label type
  *    - only fdisk_write_disklabel() modify on-disk data
  *
- * in-memory data
+ * in-memory label data
  *    - generic data and disklabel specific data stored in struct fdisk_label
  *    - all partitioning operations are based on in-memory data only
  *
@@ -31,8 +31,12 @@
  *    - provides abstraction to present partitions to users
  *    - fdisk_partition is possible to gather to fdisk_table container
  *    - used as unified template for new partitions
+ *    - used (with fdisk_table) in fdisk scripts
  *    - the struct fdisk_partition is always completely independent object and
  *      any change to the object has no effect to in-memory (or on-disk) label data
+ *
+ * Don't forget to inform kernel about changes by fdisk_reread_partition_table()
+ * or more smart fdisk_reread_changes().
  */
 
 /**
@@ -483,7 +487,7 @@ int fdisk_is_ptcollision(struct fdisk_context *cxt)
  * </informalexample>
  *
  * Note that the recommended way to list partitions is to use
- * fdisk_get_partitions() and struct fdisk_table than ask disk driver for each
+ * fdisk_get_partitions() and struct fdisk_table then ask disk driver for each
  * individual partitions.
  *
  * Returns: maximal number of partitions for the current label.
@@ -537,7 +541,7 @@ static void reset_context(struct fdisk_context *cxt)
 			free(cxt->firstsector);
 	} else {
 		/* we close device only in primary context */
-		if (cxt->dev_fd > -1)
+		if (cxt->dev_fd > -1 && cxt->private_fd)
 			close(cxt->dev_fd);
 		free(cxt->firstsector);
 	}
@@ -555,6 +559,7 @@ static void reset_context(struct fdisk_context *cxt)
 	memset(&cxt->dev_st, 0, sizeof(cxt->dev_st));
 
 	cxt->dev_fd = -1;
+	cxt->private_fd = 0;
 	cxt->firstsector = NULL;
 	cxt->firstsector_bufsz = 0;
 
@@ -568,30 +573,12 @@ static void reset_context(struct fdisk_context *cxt)
 	fdisk_free_wipe_areas(cxt);
 }
 
-/**
- * fdisk_assign_device:
- * @cxt: context
- * @fname: path to the device to be handled
- * @readonly: how to open the device
- *
- * Open the device, discovery topology, geometry, detect disklabel and switch
- * the current label driver to reflect the probing result.
- *
- * Note that this function resets all generic setting in context. If the @cxt
- * is nested context then the device is assigned to the parental context and
- * necessary properties are copied to the @cxt. The change is propagated in
- * child->parent direction only. It's impossible to use a different device for
- * primary and nested contexts.
- *
- * Returns: 0 on success, < 0 on error.
- */
-int fdisk_assign_device(struct fdisk_context *cxt,
-			const char *fname, int readonly)
+/* fdisk_assign_device() body */
+static int fdisk_assign_fd(struct fdisk_context *cxt, int fd,
+			const char *fname, int readonly, int privfd)
 {
-	int fd;
-
-	DBG(CXT, ul_debugobj(cxt, "assigning device %s", fname));
 	assert(cxt);
+	assert(fd >= 0);
 
 	/* redirect request to parent */
 	if (cxt->parent) {
@@ -602,7 +589,7 @@ int fdisk_assign_device(struct fdisk_context *cxt,
 		 * unwanted extra warnings. */
 		fdisk_enable_listonly(cxt->parent, fdisk_is_listonly(cxt));
 
-		rc = fdisk_assign_device(cxt->parent, fname, readonly);
+		rc = fdisk_assign_fd(cxt->parent, fd, fname, readonly, privfd);
 		fdisk_enable_listonly(cxt->parent, org);
 
 		if (!rc)
@@ -614,16 +601,13 @@ int fdisk_assign_device(struct fdisk_context *cxt,
 
 	reset_context(cxt);
 
-	fd = open(fname, (readonly ? O_RDONLY : O_RDWR ) | O_CLOEXEC);
-	if (fd < 0)
-		goto fail;
-
 	if (fstat(fd, &cxt->dev_st) != 0)
 		goto fail;
 
 	cxt->readonly = readonly;
 	cxt->dev_fd = fd;
-	cxt->dev_path = strdup(fname);
+	cxt->private_fd = privfd;
+	cxt->dev_path = fname ? strdup(fname) : NULL;
 	if (!cxt->dev_path)
 		goto fail;
 
@@ -635,15 +619,20 @@ int fdisk_assign_device(struct fdisk_context *cxt,
 	if (fdisk_read_firstsector(cxt) < 0)
 		goto fail;
 
-	fdisk_probe_labels(cxt);
+	/* warn about obsolete stuff on the device if we aren't in list-only */
+	if (!fdisk_is_listonly(cxt) && fdisk_check_collisions(cxt) < 0)
+		goto fail;
 
+	fdisk_probe_labels(cxt);
 	fdisk_apply_label_device_properties(cxt);
 
-	/* warn about obsolete stuff on the device if we aren't in
-	 * list-only mode and there is not PT yet */
-	if (!fdisk_is_listonly(cxt) && !fdisk_has_label(cxt)
-	    && fdisk_check_collisions(cxt) < 0)
-		goto fail;
+	/* Don't report collision if there is already a valid partition table.
+	 * The bootbits are wiped when we create a *new* partition table only. */
+	if (fdisk_is_ptcollision(cxt) && fdisk_has_label(cxt)) {
+		cxt->pt_collision = 0;
+		free(cxt->collision);
+		cxt->collision = NULL;
+	}
 
 	DBG(CXT, ul_debugobj(cxt, "initialized for %s [%s]",
 			      fname, readonly ? "READ-ONLY" : "READ-WRITE"));
@@ -651,19 +640,84 @@ int fdisk_assign_device(struct fdisk_context *cxt,
 fail:
 	{
 		int rc = -errno;
-		if (fd >= 0)
-			close(fd);
 		DBG(CXT, ul_debugobj(cxt, "failed to assign device [rc=%d]", rc));
 		return rc;
 	}
 }
 
 /**
+ * fdisk_assign_device:
+ * @cxt: context
+ * @fname: path to the device to be handled
+ * @readonly: how to open the device
+ *
+ * Open the device, discovery topology, geometry, detect disklabel, check for
+ * collisions and switch the current label driver to reflect the probing
+ * result.
+ *
+ * If in standard mode (!= non-listonly mode) then also detects for collisions.
+ * The result is accessible by fdisk_get_collision() and
+ * fdisk_is_ptcollision().  The collision (e.g. old obsolete PT) may be removed
+ * by fdisk_enable_wipe().  Note that new PT and old PT may be on different
+ * locations.
+ *
+ * Note that this function resets all generic setting in context.
+ *
+ * If the @cxt is nested context (necessary for example to edit BSD or PMBR)
+ * then the device is assigned to the parental context and necessary properties
+ * are copied to the @cxt. The change is propagated in child->parent direction
+ * only. It's impossible to use a different device for primary and nested
+ * contexts.
+ *
+ * Returns: 0 on success, < 0 on error.
+ */
+int fdisk_assign_device(struct fdisk_context *cxt,
+			const char *fname, int readonly)
+{
+	int fd, rc;
+
+	DBG(CXT, ul_debugobj(cxt, "assigning device %s", fname));
+	assert(cxt);
+
+	fd = open(fname, (readonly ? O_RDONLY : O_RDWR ) | O_CLOEXEC);
+	if (fd < 0) {
+		rc = -errno;
+		DBG(CXT, ul_debugobj(cxt, "failed to assign device [rc=%d]", rc));
+		return rc;
+	}
+
+	rc = fdisk_assign_fd(cxt, fd, fname, readonly, 1);
+	if (rc)
+		close(fd);
+	return rc;
+}
+
+/**
+ * fdisk_assign_device_by_fd:
+ * @cxt: context
+ * @fd: device file descriptor
+ * @fname: path to the device (used for dialogs, debugging, partition names, ...)
+ * @readonly: how to use the device
+ *
+ * Like fdisk_assign_device(), but caller is responsible to open and close the
+ * device. The library only fsync() the device on fdisk_deassign_device().
+ *
+ * The device has to be open O_RDWR on @readonly=0.
+ *
+ * Returns: 0 on success, < 0 on error.
+ */
+int fdisk_assign_device_by_fd(struct fdisk_context *cxt, int fd,
+			const char *fname, int readonly)
+{
+	return fdisk_assign_fd(cxt, fd, fname, readonly, 0);
+}
+
+/**
  * fdisk_deassign_device:
  * @cxt: context
  * @nosync: disable fsync()
  *
- * Close device and call fsync(). If the @cxt is nested context than the
+ * Close device and call fsync(). If the @cxt is nested context then the
  * request is redirected to the parent.
  *
  * Returns: 0 on success, < 0 on error.
@@ -683,15 +737,19 @@ int fdisk_deassign_device(struct fdisk_context *cxt, int nosync)
 
 	DBG(CXT, ul_debugobj(cxt, "de-assigning device %s", cxt->dev_path));
 
-	if (cxt->readonly)
+	if (cxt->readonly && cxt->private_fd)
 		close(cxt->dev_fd);
 	else {
-		if (fsync(cxt->dev_fd) || close(cxt->dev_fd)) {
+		if (fsync(cxt->dev_fd)) {
+			fdisk_warn(cxt, _("%s: fsync device failed"),
+					cxt->dev_path);
+			return -errno;
+		}
+		if (cxt->private_fd && close(cxt->dev_fd)) {
 			fdisk_warn(cxt, _("%s: close device failed"),
 					cxt->dev_path);
 			return -errno;
 		}
-
 		if (!nosync) {
 			fdisk_info(cxt, _("Syncing disks."));
 			sync();
@@ -700,7 +758,6 @@ int fdisk_deassign_device(struct fdisk_context *cxt, int nosync)
 
 	free(cxt->dev_path);
 	cxt->dev_path = NULL;
-
 	cxt->dev_fd = -1;
 
 	return 0;
@@ -720,7 +777,7 @@ int fdisk_deassign_device(struct fdisk_context *cxt, int nosync)
 int fdisk_reassign_device(struct fdisk_context *cxt)
 {
 	char *devname;
-	int rdonly, rc;
+	int rdonly, rc, fd, privfd;
 
 	assert(cxt);
 	assert(cxt->dev_fd >= 0);
@@ -732,11 +789,19 @@ int fdisk_reassign_device(struct fdisk_context *cxt)
 		return -ENOMEM;
 
 	rdonly = cxt->readonly;
+	fd = cxt->dev_fd;
+	privfd = cxt->private_fd;
 
 	fdisk_deassign_device(cxt, 1);
-	rc = fdisk_assign_device(cxt, devname, rdonly);
-	free(devname);
 
+	if (privfd)
+		/* reopen and assign */
+		rc = fdisk_assign_device(cxt, devname, rdonly);
+	else
+		/* assign only */
+		rc = fdisk_assign_fd(cxt, fd, devname, rdonly, privfd);
+
+	free(devname);
 	return rc;
 }
 
@@ -774,7 +839,7 @@ int fdisk_reread_partition_table(struct fdisk_context *cxt)
 		fdisk_info(cxt,	_(
 			"The kernel still uses the old table. The "
 			"new table will be used at the next reboot "
-			"or after you run partprobe(8) or kpartx(8)."));
+			"or after you run partprobe(8) or partx(8)."));
 		return -errno;
 	}