[PATCH 4/8] rework handling of data from udevinfo for more efficient memory usage

[Rob Taylor]

This patch reworks the handling of the output of udevinfo so that the 
output is
parsed into an intermediatary form (with a hash table of sysfpath to 
structures
pointing directly into the output as captured). This is converted into
HotplugEvents one at a time when needed by coldplug_get_hotplug_event.
---
  hald/linux/coldplug.c |  175 
++++++++++++++++++++++++++++++++-----------------
  1 files changed, 115 insertions(+), 60 deletions(-)

diff --git a/hald/linux/coldplug.c b/hald/linux/coldplug.c
index 3ad7199..dbc1830 100644
--- a/hald/linux/coldplug.c
+++ b/hald/linux/coldplug.c
@@ -55,23 +55,107 @@ struct sysfs_device {
  static GHashTable *sysfs_to_udev_map;
  static GSList *device_list;
  static char dev_root[HAL_PATH_MAX];
+static gchar *udevinfo_stdout = NULL;

-static void hotplug_event_free (HotplugEvent *ev)
+typedef struct _UdevInfo UdevInfo;
+
+struct _UdevInfo
+{
+	const char *sysfs_path;
+	const char *device_file;
+	const char *vendor;
+	const char *model;
+	const char *revision;
+	const char *serial;
+	const char *fsusage;
+	const char *fstype;
+	const char *fsversion;
+	const char *fsuuid;
+	const char *fslabel;
+};
+
+static void udev_info_free (gpointer data)
+{
+	g_slice_free(UdevInfo, data);
+}
+
+
+static HotplugEvent*
+udev_info_to_hotplug_event (const UdevInfo *info)
  {
-	g_slice_free(HotplugEvent, ev);
+	HotplugEvent *hotplug_event;
+	gchar *str;
+
+	hotplug_event = g_slice_new0 (HotplugEvent);
+	g_strlcpy (hotplug_event->sysfs.sysfs_path, "/sys", 
sizeof(hotplug_event->sysfs.sysfs_path));
+	g_strlcat (hotplug_event->sysfs.sysfs_path, info->sysfs_path, 
sizeof(hotplug_event->sysfs.sysfs_path));
+
+	HAL_INFO(("creating HotplugEvent for %s", 
hotplug_event->sysfs.sysfs_path));
+
+	if (info->device_file) {
+		g_snprintf (hotplug_event->sysfs.device_file, 
sizeof(hotplug_event->sysfs.device_file),
+			"%s/%s", dev_root, info->device_file);
+	HAL_INFO(("with device file %s", hotplug_event->sysfs.device_file));
+	}
+	if ((str = hal_util_strdup_valid_utf8(info->vendor)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.vendor, str, 
sizeof(hotplug_event->sysfs.vendor));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->model)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.model, str, 
sizeof(hotplug_event->sysfs.model));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->revision)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.revision, str, 
sizeof(hotplug_event->sysfs.revision));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->serial)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.serial, str, 
sizeof(hotplug_event->sysfs.serial));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->fsusage)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.fsusage, str, 
sizeof(hotplug_event->sysfs.fsusage));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->fstype)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.fstype, str, 
sizeof(hotplug_event->sysfs.fstype));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->fsversion)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.fsversion, str, 
sizeof(hotplug_event->sysfs.fsversion));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->fsuuid)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.fsuuid, str, 
sizeof(hotplug_event->sysfs.fsuuid));
+		g_free (str);
+	}
+
+	if ((str = hal_util_strdup_valid_utf8(info->fslabel)) != NULL) {
+		g_strlcpy (hotplug_event->sysfs.fslabel, str, 
sizeof(hotplug_event->sysfs.fslabel));
+		g_free (str);
+	}
+
+	return hotplug_event;
  }

+
  static gboolean
  hal_util_init_sysfs_to_udev_map (void)
  {
  	char *udevdb_export_argv[] = { "/usr/bin/udevinfo", "-e", NULL };
  	char *udevroot_argv[] = { "/usr/bin/udevinfo", "-r", NULL };
-	char *udevinfo_stdout;
  	int udevinfo_exitcode;
-	HotplugEvent *hotplug_event = NULL;
+	UdevInfo *info = NULL;
  	char *p;

-	sysfs_to_udev_map = g_hash_table_new_full (g_str_hash, g_str_equal, 
g_free, hotplug_event_free);
+	sysfs_to_udev_map = g_hash_table_new_full (g_str_hash, g_str_equal, 
g_free, udev_info_free);

  	/* get udevroot */
  	if (g_spawn_sync ("/", udevroot_argv, NULL, 0, NULL, NULL,
@@ -114,7 +198,6 @@ hal_util_init_sysfs_to_udev_map (void)
  	p = udevinfo_stdout;
  	while (p[0] != '\0') {
  		char *line, *end;
-		gchar *str;

  		/* get line, terminate and move to next line */
  		line = p;
@@ -126,79 +209,49 @@ hal_util_init_sysfs_to_udev_map (void)

  		/* insert device */
  		if (line[0] == '\0') {
-			if (hotplug_event != NULL) {
-				g_hash_table_insert (sysfs_to_udev_map, g_strdup 
(hotplug_event->sysfs.sysfs_path), hotplug_event);
-				HAL_INFO (("found (udevdb export) '%s' -> '%s'",
-					   hotplug_event->sysfs.sysfs_path, 
hotplug_event->sysfs.device_file));
-				hotplug_event = NULL;
+			if (info != NULL) {
+				g_hash_table_insert (sysfs_to_udev_map, g_strdup_printf ("/sys%s", 
info->sysfs_path), info);
+				HAL_INFO (("found (udevdb export) '/sys%s' -> '%s/%s'",
+					   info->sysfs_path, dev_root, info->device_file));
+				info = NULL;
  			}
  			continue;
  		}

  		/* new device */
  		if (strncmp(line, "P: ", 3) == 0) {
-			hotplug_event = g_slice_new0 (HotplugEvent);
-			g_strlcpy (hotplug_event->sysfs.sysfs_path, "/sys", 
sizeof(hotplug_event->sysfs.sysfs_path));
-			g_strlcat (hotplug_event->sysfs.sysfs_path, &line[3], 
sizeof(hotplug_event->sysfs.sysfs_path));
+			info = g_slice_new0 (UdevInfo);
+			info->sysfs_path = &line[3];
  			continue;
  		}

  		/* only valid if we have an actual device */
-		if (hotplug_event == NULL)
+		if (info == NULL)
  			continue;

  		if (strncmp(line, "N: ", 3) == 0) {
-			g_snprintf (hotplug_event->sysfs.device_file, 
sizeof(hotplug_event->sysfs.device_file),
-				    "%s/%s", dev_root, &line[3]);
+			info->device_file = &line[3];
  		} else if (strncmp(line, "E: ID_VENDOR=", 13) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[13])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.vendor, str, 
sizeof(hotplug_event->sysfs.vendor));
-				g_free (str);
-			}
+			info->vendor = &line[13];
  		} else if (strncmp(line, "E: ID_MODEL=", 12) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[12])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.model, str, 
sizeof(hotplug_event->sysfs.model));
-				g_free (str);
-			}
+			info->model = &line[12];
  		} else if (strncmp(line, "E: ID_REVISION=", 15) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[15])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.revision, str, 
sizeof(hotplug_event->sysfs.revision));
-				g_free (str);
-			}
+			info->revision = &line[15];
  		} else if (strncmp(line, "E: ID_SERIAL=", 13) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[13])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.serial, str, 
sizeof(hotplug_event->sysfs.serial));
-				g_free (str);
-			}
+			info->serial = &line[13];
  		} else if (strncmp(line, "E: ID_FS_USAGE=", 15) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[15])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.fsusage, str, 
sizeof(hotplug_event->sysfs.fsusage));
-				g_free (str);
-			}
+			info->fsusage = &line[15];
  		} else if (strncmp(line, "E: ID_FS_TYPE=", 14) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[14])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.fstype, str, 
sizeof(hotplug_event->sysfs.fstype));
-				g_free (str);
-			}
+			info->fstype = &line[14];
  		} else if (strncmp(line, "E: ID_FS_VERSION=", 17) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[17])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.fsversion, str, 
sizeof(hotplug_event->sysfs.fsversion));
-				g_free (str);
-			}
+			info->fsversion = &line[17];
  		} else if (strncmp(line, "E: ID_FS_UUID=", 14) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[14])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.fsuuid, str, 
sizeof(hotplug_event->sysfs.fsuuid));
-				g_free (str);
-			}
+			info->fsuuid = &line[14];
  		} else if (strncmp(line, "E: ID_FS_LABEL=", 15) == 0) {
-			if ((str = hal_util_strdup_valid_utf8(&line[15])) != NULL) {
-				g_strlcpy (hotplug_event->sysfs.fslabel, str, 
sizeof(hotplug_event->sysfs.fslabel));
-				g_free (str);
-			}
+			info->fslabel = &line[15];
  		}
  	}

-	g_free(udevinfo_stdout);
  	return TRUE;

  error:
@@ -211,19 +264,20 @@ error:
  static HotplugEvent
  *coldplug_get_hotplug_event(const gchar *sysfs_path, const gchar 
*subsystem, HotplugEventType type)
  {
-	HotplugEvent *hotplug_event, *hotplug_event_udev;
+	HotplugEvent *hotplug_event;
  	const char *pos;
  	gchar path[HAL_PATH_MAX];
  	struct stat statbuf;
-
-	hotplug_event = g_slice_new0 (HotplugEvent);
+	UdevInfo *info;

  	/* lookup if udev has something stored in its database */
-	hotplug_event_udev = (HotplugEvent *) g_hash_table_lookup 
(sysfs_to_udev_map, sysfs_path);
-	if (hotplug_event_udev != NULL) {
-		memcpy(hotplug_event, hotplug_event_udev, sizeof(HotplugEvent));
+	info = (UdevInfo*) g_hash_table_lookup (sysfs_to_udev_map, sysfs_path);
+	if (info) {
+		hotplug_event = udev_info_to_hotplug_event (info);
  		HAL_INFO (("new event (dev node from udev) '%s' '%s'", 
hotplug_event->sysfs.sysfs_path, hotplug_event->sysfs.device_file));
  	} else {
+		hotplug_event = g_slice_new0 (HotplugEvent);
+
  		/* device is not in udev database */
  		g_strlcpy(hotplug_event->sysfs.sysfs_path, sysfs_path, 
sizeof(hotplug_event->sysfs.sysfs_path));

@@ -543,6 +597,7 @@ coldplug_synthesize_events (void)
  	}

  	g_hash_table_destroy (sysfs_to_udev_map);
+	g_free (udevinfo_stdout);
  	return TRUE;

  error: