Add 'notmuch count' command to show the count of matching messages

Getting the count of matching threads or messages is a fairly
expensive operation. Xapian provides a very efficient mechanism that
returns an approximate value, so use that for this new command.

This returns the number of matching messages, not threads, as that is
cheap to compute.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 110 insertions, 0 deletions

diff --git a/notmuch-count.c b/notmuch-count.c
new file mode 100644
index 00000000..77aa4338
--- /dev/null
+++ b/notmuch-count.c
@@ -0,0 +1,110 @@
+/* notmuch - Not much of an email program, (just index and search)
+ *
+ * Copyright © 2009 Carl Worth
+ * Copyright © 2009 Keith Packard
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see http://www.gnu.org/licenses/ .
+ *
+ * Author: Keith Packard <keithp@keithp.com>
+ */
+
+#include "notmuch-client.h"
+
+int
+notmuch_count_command (void *ctx, int argc, char *argv[])
+{
+    notmuch_config_t *config;
+    notmuch_database_t *notmuch;
+    notmuch_query_t *query;
+    char *query_str;
+    int i;
+#if 0
+    char *opt, *end;
+    int i, first = 0, max_threads = -1;
+    notmuch_sort_t sort = NOTMUCH_SORT_NEWEST_FIRST;
+#endif
+
+    for (i = 0; i < argc && argv[i][0] == '-'; i++) {
+	if (strcmp (argv[i], "--") == 0) {
+	    i++;
+	    break;
+	}
+#if 0
+	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) {
+	    opt = argv[i] + sizeof ("--sort=") - 1;
+	    if (strcmp (opt, "oldest-first") == 0) {
+		sort = NOTMUCH_SORT_OLDEST_FIRST;
+	    } else if (strcmp (opt, "newest-first") == 0) {
+		sort = NOTMUCH_SORT_NEWEST_FIRST;
+	    } else {
+		fprintf (stderr, "Invalid value for --sort: %s\n", opt);
+		return 1;
+	    }
+	} else
+#endif
+	{
+	    fprintf (stderr, "Unrecognized option: %s\n", argv[i]);
+	    return 1;
+	}
+    }
+
+    argc -= i;
+    argv += i;
+
+    config = notmuch_config_open (ctx, NULL, NULL);
+    if (config == NULL)
+	return 1;
+
+    notmuch = notmuch_database_open (notmuch_config_get_database_path (config),
+				     NOTMUCH_DATABASE_MODE_READ_ONLY);
+    if (notmuch == NULL)
+	return 1;
+
+    query_str = query_string_from_args (ctx, argc, argv);
+    if (query_str == NULL) {
+	fprintf (stderr, "Out of memory.\n");
+	return 1;
+    }
+    if (*query_str == '\0') {
+	fprintf (stderr, "Error: notmuch count requires at least one count term.\n");
+	return 1;
+    }
+
+    query = notmuch_query_create (notmuch, query_str);
+    if (query == NULL) {
+	fprintf (stderr, "Out of memory\n");
+	return 1;
+    }
+
+    printf ("%u\n", notmuch_query_count_messages(query));
+
+    notmuch_query_destroy (query);
+    notmuch_database_close (notmuch);
+
+    return 0;
+}