notmuch search: Remove the chunked-searching hack.

This was a poor workaround around the fact that the existing
notmuch_threads_t object is implemented poorly. It's got a fine
iterartor-based interface, but the implementation does all of the
work up-front in _create rather than doing the work incrementally
while iterating.

So to start fixing this, first get rid of all the hacks we had working
around this. This drops the --first and --max-threads options from the
search command, (but hopefully nobody was using them
anyway---notmuch.el certainly wasn't).

6 files changed, 25 insertions, 144 deletions

diff --git a/lib/notmuch.h b/lib/notmuch.h
index 260cc22d..9b40fb69 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -322,14 +322,6 @@ notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
  * object is owned by the query and as such, will only be valid until
  * notmuch_query_destroy.
  *
- * The 'first' and 'max_threads' arguments can be used to obtain
- * partial results from the search. For example, to get results 10 at
- * a time, pass 'max_threads' as 10 and for 'first' pass the values 0,
- * 10, 20, etc. As a special case, a value of -1 for 'max_threads'
- * indicates that no limiting is to be performed. So a search with
- * 'first' == 0 and 'max_threads' == -1 will return the complete
- * results of the search.
- *
  * Typical usage might be:
  *
  *     notmuch_query_t *query;
@@ -362,8 +354,7 @@ notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
  * to call it if the query is about to be destroyed).
  */
 notmuch_threads_t *
-notmuch_query_search_threads (notmuch_query_t *query,
-			      int first, int max_threads);
+notmuch_query_search_threads (notmuch_query_t *query);
 
 /* Execute a query for messages, returning a notmuch_messages_t object
  * which can be used to iterate over the results. The returned
diff --git a/lib/query.cc b/lib/query.cc
index 686d75f9..13bdd0a1 100644
--- a/lib/query.cc
+++ b/lib/query.cc
@@ -171,9 +171,7 @@ _notmuch_threads_destructor (notmuch_threads_t *threads)
 }
 
 notmuch_threads_t *
-notmuch_query_search_threads (notmuch_query_t *query,
-			      int first,
-			      int max_threads)
+notmuch_query_search_threads (notmuch_query_t *query)
 {
     notmuch_threads_t *threads;
     notmuch_thread_t *thread;
@@ -181,7 +179,6 @@ notmuch_query_search_threads (notmuch_query_t *query,
     notmuch_messages_t *messages;
     notmuch_message_t *message;
     GHashTable *seen;
-    int messages_seen = 0, threads_seen = 0;
 
     threads = talloc (query, notmuch_threads_t);
     if (threads == NULL)
@@ -196,49 +193,27 @@ notmuch_query_search_threads (notmuch_query_t *query,
     seen = g_hash_table_new_full (g_str_hash, g_str_equal,
 				  free, NULL);
 
-    while (max_threads < 0 || threads_seen < first + max_threads)
+    for (messages = notmuch_query_search_messages (query, 0, -1);
+	 notmuch_messages_has_more (messages);
+	 notmuch_messages_advance (messages))
     {
-	int messages_seen_previously = messages_seen;
+	message = notmuch_messages_get (messages);
 
-	for (messages = notmuch_query_search_messages (query,
-						       messages_seen,
-						       max_threads);
-	     notmuch_messages_has_more (messages);
-	     notmuch_messages_advance (messages))
-	{
-	    message = notmuch_messages_get (messages);
-
-	    thread_id = notmuch_message_get_thread_id (message);
-
-	    if (! g_hash_table_lookup_extended (seen,
-						thread_id, NULL,
-						(void **) &thread))
-	    {
-		if (threads_seen >= first) {
-		    thread = _notmuch_thread_create (query, query->notmuch,
-						     thread_id,
-						     query->query_string);
-		    g_ptr_array_add (threads->threads, thread);
-		} else {
-		    thread = NULL;
-		}
-
-		g_hash_table_insert (seen, xstrdup (thread_id), thread);
-
-		threads_seen++;
-	    }
+	thread_id = notmuch_message_get_thread_id (message);
 
-	    notmuch_message_destroy (message);
-
-	    messages_seen++;
+	if (! g_hash_table_lookup_extended (seen,
+					    thread_id, NULL,
+					    (void **) &thread))
+	{
+	    thread = _notmuch_thread_create (query, query->notmuch,
+					     thread_id,
+					     query->query_string);
+	    g_ptr_array_add (threads->threads, thread);
 
-	    if (max_threads >= 0 && threads_seen >= first + max_threads)
-		break;
+	    g_hash_table_insert (seen, xstrdup (thread_id), thread);
 	}
 
-	/* Stop if we're not seeing any more messages. */
-	if (messages_seen == messages_seen_previously)
-	    break;
+	notmuch_message_destroy (message);
     }
 
     g_hash_table_unref (seen);
diff --git a/notmuch-search.c b/notmuch-search.c
index fc2baaa7..dc44eb66 100644
--- a/notmuch-search.c
+++ b/notmuch-search.c
@@ -20,40 +20,24 @@
 
 #include "notmuch-client.h"
 
-/* If the user asks for more than this number of threads, then break
-   the results down into chunks so that results start appearing
-   quickly rather than the user having to wait until all results are
-   available before anything appears.
-
-   Since each subsequent chunk ends up having to re-do threading work
-   done by all previous chunks, we double the chunk size repeatedly
-   until all desired results have been returned.
-*/
-#define NOTMUCH_SEARCH_INITIAL_CHUNK_SIZE 100
-
-/* Do the actual search for a chunk of threads and display the results,
-   (returning the number of threads found in this chunk). */
-static int
+static void
 do_search_threads (const void *ctx,
 		   notmuch_query_t *query,
-		   notmuch_sort_t sort,
-		   int first, int max_threads)
+		   notmuch_sort_t sort)
 {
     notmuch_thread_t *thread;
     notmuch_threads_t *threads;
     notmuch_tags_t *tags;
     time_t date;
     const char *relative_date;
-    int num_threads = 0;
 
-    for (threads = notmuch_query_search_threads (query, first, max_threads);
+    for (threads = notmuch_query_search_threads (query);
 	 notmuch_threads_has_more (threads);
 	 notmuch_threads_advance (threads))
     {
 	int first_tag = 1;
 
 	thread = notmuch_threads_get (threads);
-	num_threads++;
 
 	if (sort == NOTMUCH_SORT_OLDEST_FIRST)
 	    date = notmuch_thread_get_oldest_date (thread);
@@ -84,8 +68,6 @@ do_search_threads (const void *ctx,
 
 	notmuch_thread_destroy (thread);
     }
-
-    return num_threads;
 }
 
 int
@@ -95,32 +77,16 @@ notmuch_search_command (void *ctx, int argc, char *argv[])
     notmuch_database_t *notmuch;
     notmuch_query_t *query;
     char *query_str;
-    int i, first = 0, max_threads = -1;
-    char *opt, *end;
+    char *opt;
     notmuch_sort_t sort = NOTMUCH_SORT_NEWEST_FIRST;
-    int chunk_size;
-    int threads_in_chunk;
+    int i;
 
     for (i = 0; i < argc && argv[i][0] == '-'; i++) {
 	if (strcmp (argv[i], "--") == 0) {
 	    i++;
 	    break;
 	}
-	if (STRNCMP_LITERAL (argv[i], "--first=") == 0) {
-	    opt = argv[i] + sizeof ("--first=") - 1;
-	    first = strtoul (opt, &end, 10);
-	    if (*opt == '\0' || *end != '\0') {
-		fprintf (stderr, "Invalid value for --first: %s\n", opt);
-		return 1;
-	    }
-	} else if (STRNCMP_LITERAL (argv[i], "--max-threads=") == 0) {
-	    opt = argv[i] + sizeof ("--max-threads=") - 1;
-	    max_threads = strtoul (opt, &end, 10);
-	    if (*opt == '\0' || *end != '\0') {
-		fprintf (stderr, "Invalid value for --max-threads: %s\n", opt);
-		return 1;
-	    }
-	} else if (STRNCMP_LITERAL (argv[i], "--sort=") == 0) {
+        if (STRNCMP_LITERAL (argv[i], "--sort=") == 0) {
 	    opt = argv[i] + sizeof ("--sort=") - 1;
 	    if (strcmp (opt, "oldest-first") == 0) {
 		sort = NOTMUCH_SORT_OLDEST_FIRST;
@@ -166,25 +132,7 @@ notmuch_search_command (void *ctx, int argc, char *argv[])
 
     notmuch_query_set_sort (query, sort);
 
-    /* If we receive a max-threads option, then the user is
-       responsible for any chunking and we return all results at
-       once. */
-    if (max_threads < 0)
-	chunk_size = NOTMUCH_SEARCH_INITIAL_CHUNK_SIZE;
-    else
-	chunk_size = max_threads;
-
-    do {
-	threads_in_chunk = do_search_threads (ctx, query, sort,
-					      first, chunk_size);
-	if (chunk_size == max_threads)
-	    break;
-
-	first += chunk_size;
-
-	chunk_size *= 2;
-
-    } while (threads_in_chunk);
+    do_search_threads (ctx, query, sort);
 
     notmuch_query_destroy (query);
     notmuch_database_close (notmuch);
diff --git a/notmuch-show.c b/notmuch-show.c
index c7f13204..edebacaa 100644
--- a/notmuch-show.c
+++ b/notmuch-show.c
@@ -238,7 +238,7 @@ notmuch_show_command (void *ctx, unused (int argc), unused (char *argv[]))
 	return 1;
     }
 
-    for (threads = notmuch_query_search_threads (query, 0, -1);
+    for (threads = notmuch_query_search_threads (query);
 	 notmuch_threads_has_more (threads);
 	 notmuch_threads_advance (threads))
     {
diff --git a/notmuch.1 b/notmuch.1
index c5a7711f..2be77f99 100644
--- a/notmuch.1
+++ b/notmuch.1
@@ -154,29 +154,6 @@ Supported options for
 include
 .RS 4
 .TP 4
-.BR \-\-max\-threads= <value>
-
-Restricts displayed search results to a subset of the complete results
-that would match the terms. With this option, no more than <value>
-thread results will be displayed. If this option is not used, then all
-matching threads will be displayed. See also the
-.B \-\-first
-option.
-
-.TP
-.BR \-\-first= <value>
-
-Omits the first <value> threads from the search results that would
-otherwise be displayed. Together with the
-.BR \-\-max\-threads
-option, this can be used to perform incremental searches. For example,
-the first 50 thread results can be displayed with
-.B "\-\-first=0 \-\-max\-threads=50"
-and the next 50 could be displayed with
-.B "\-\-first=50 \-\-max\-threads=50"
-etc.
-
-.TP
 .BR \-\-sort= ( newest\-first | oldest\-first )
 
 This option can be used to present results in either chronological order
diff --git a/notmuch.c b/notmuch.c
index b84e2844..f45b6924 100644
--- a/notmuch.c
+++ b/notmuch.c
@@ -162,16 +162,6 @@ command_t commands[] = {
       "\n"
       "\t\tSupported options for search include:\n"
       "\n"
-      "\t\t--max-threads=<value>\n"
-      "\n"
-      "\t\t\tRestricts displayed search results to a subset\n"
-      "\t\t\tof the results that would match the terms.\n"
-      "\n"
-      "\t\t--first=<value>\n"
-      "\n"
-      "\t\t\tOmits the first <value> threads from the search\n"
-      "\t\t\tresults that would otherwise be displayed.\n"
-      "\n"
       "\t\t--sort=(newest-first|oldest-first)\n"
       "\n"
       "\t\t\tPresent results in either chronological order\n"