From: David Bremner <bremner@debian.org>

This is format is whitespace separated tokens, encoded by
util/hex-escape.c
---
 notmuch-restore.c |   81 +++++++++++++++++++++++++++++++++++++++++------------
 1 files changed, 63 insertions(+), 18 deletions(-)

diff --git a/notmuch-restore.c b/notmuch-restore.c
index 87d9772..f618b47 100644
--- a/notmuch-restore.c
+++ b/notmuch-restore.c
@@ -19,6 +19,7 @@
  */
 
 #include "notmuch-client.h"
+#include "dump-restore-private.h"
 
 int
 notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
@@ -35,6 +36,7 @@ notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
     regex_t regex;
     int rerr;
     int opt_index;
+    int input_format = DUMP_FORMAT_SUP;
 
     config = notmuch_config_open (ctx, NULL, NULL);
     if (config == NULL)
@@ -48,6 +50,7 @@ notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
     synchronize_flags = notmuch_config_get_maildir_synchronize_flags (config);
 
     notmuch_opt_desc_t options[] = {
+	FORMAT_DESC (input_format),
 	{ NOTMUCH_OPT_POSITION, &input_file_name, 0, 0, 0 },
 	{ NOTMUCH_OPT_BOOLEAN,  &accumulate, "accumulate", 'a', 0 },
 	{ 0, 0, 0, 0, 0 }
@@ -81,33 +84,63 @@ notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
      * non-space characters for the message-id, then one or more
      * spaces, then a list of space-separated tags as a sequence of
      * characters within literal '(' and ')'. */
-    if ( xregcomp (&regex,
-		   "^([^ ]+) \\(([^)]*)\\)$",
-		   REG_EXTENDED) )
-	INTERNAL_ERROR("compile time constant regex failed.");
+    if (input_format == DUMP_FORMAT_SUP) {
+	if ( xregcomp (&regex,
+		       "^([^ ]+) \\(([^)]*)\\)$",
+		       REG_EXTENDED) )
+	    INTERNAL_ERROR("compile time constant regex failed.");
+    }
+
+
+    /* These are out here to re-use the buffers with hex_decode */
+
+    char *message_id = NULL;
+    size_t message_id_size = 0;
+    char *tag = NULL;
+    size_t tag_size = 0;
 
     while ((line_len = getline (&line, &line_size, input)) != -1) {
 	regmatch_t match[3];
-	char *message_id, *file_tags, *tag, *next;
+	char  *file_tags, *next;
 	notmuch_message_t *message = NULL;
+
 	notmuch_status_t status;
 	notmuch_tags_t *db_tags;
 	char *db_tags_str;
 
 	chomp_newline (line);
 
-	rerr = xregexec (&regex, line, 3, match, 0);
-	if (rerr == REG_NOMATCH)
-	{
-	    fprintf (stderr, "Warning: Ignoring invalid input line: %s\n",
-		     line);
+	/* Silently ignore blank lines */
+
+	if (line[0] == '\0') {
 	    continue;
 	}
 
-	message_id = xstrndup (line + match[1].rm_so,
-			       match[1].rm_eo - match[1].rm_so);
-	file_tags = xstrndup (line + match[2].rm_so,
-			      match[2].rm_eo - match[2].rm_so);
+	if (input_format == DUMP_FORMAT_SUP) {
+	    rerr = xregexec (&regex, line, 3, match, 0);
+	    if (rerr == REG_NOMATCH)
+	    {
+		fprintf (stderr, "Warning: Ignoring invalid input line: %s\n",
+			 line);
+		continue;
+	    }
+	    message_id = talloc_strndup (notmuch, line + match[1].rm_so,
+					 match[1].rm_eo - match[1].rm_so);
+	    file_tags = talloc_strndup (notmuch, line + match[2].rm_so,
+					match[2].rm_eo - match[2].rm_so);
+	} else {
+	    char *p = line;
+	    char *raw_mid;
+
+	    raw_mid = strsep (&p, " \t");
+
+	    if (hex_decode (notmuch, raw_mid,
+			    &message_id, &message_id_size) != HEX_SUCCESS)
+		return 1;
+
+	    file_tags = xstrdup (p);
+	}
+
 
 	status = notmuch_database_find_message (notmuch, message_id, &message);
 	if (status || message == NULL) {
@@ -153,7 +186,16 @@ notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
 
 	next = file_tags;
 	while (next) {
-	    tag = strsep (&next, " ");
+	    char *raw_tag = strsep (&next, " ");
+
+	    if (input_format == DUMP_FORMAT_NOTMUCH) {
+		if (hex_decode (notmuch, raw_tag,
+				&tag, &tag_size) != HEX_SUCCESS)
+		    return 1;
+	    } else {
+		tag = talloc_strdup (notmuch, raw_tag);
+	    }
+
 	    if (*tag == '\0')
 		continue;
 	    status = notmuch_message_add_tag (message, tag);
@@ -175,11 +217,14 @@ notmuch_restore_command (unused (void *ctx), int argc, char *argv[])
 	if (message)
 	    notmuch_message_destroy (message);
 	message = NULL;
-	free (message_id);
-	free (file_tags);
+	if (input_format == DUMP_FORMAT_SUP) {
+	    talloc_free (message_id);
+	    talloc_free (file_tags);
+	}
     }
 
-    regfree (&regex);
+    if (input_format == DUMP_FORMAT_SUP)
+	regfree (&regex);
 
     if (line)
 	free (line);
-- 
1.7.7.3