Add sup-compatible prefixes and achieve sup-compatible print output

What I've done here is to instrument sup-sync to print the text
and terms objects it constructs just before indexing a message.
Then I've made my g_mime_test program achieve (nearly) identical
output for an example email message, (just missing the body
text). Next we can start shoving this data into a Xapian index.

g_mime_test.c

@@ -21,18 +21,128 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <time.h>
 
 #include <gmime/gmime.h>
 
 #define ARRAY_SIZE(arr) (sizeof (arr) / sizeof (arr[0]))
 
-static void
-print_header (const char *name, const char *value)
+/* These prefix values are specifically chosen to be compatible
+ * with sup, (http://sup.rubyforge.org), written by
+ * William Morgan <wmorgan-sup@masanjin.net>, and released
+ * under the GNU GPL v2.
+ */
+
+typedef struct {
+    const char *name;
+    const char *prefix;
+} prefix_t;
+
+prefix_t NORMAL_PREFIX[] = {
+    { "subject", "S" },
+    { "body", "B" },
+    { "from_name", "FN" },
+    { "to_name", "TN" },
+    { "name", "N" },
+    { "attachment", "A" }
+};
+
+prefix_t BOOLEAN_PREFIX[] = {
+    { "type", "K" },
+    { "from_email", "FE" },
+    { "to_email", "TE" },
+    { "email", "E" },
+    { "date", "D" },
+    { "label", "L" },
+    { "source_id", "I" },
+    { "attachment_extension", "O" },
+    { "msgid", "Q" },
+    { "thread", "H" },
+    { "ref", "R" }
+};
+
+static const char *
+find_prefix (const char *name)
 {
-    printf ("%s:", name);
-    if (value)
-	printf ("\t%s", value);
-    printf ("\n");
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE (NORMAL_PREFIX); i++)
+	if (strcmp (name, NORMAL_PREFIX[i].name) == 0)
+	    return NORMAL_PREFIX[i].prefix;
+
+    for (i = 0; i < ARRAY_SIZE (BOOLEAN_PREFIX); i++)
+	if (strcmp (name, BOOLEAN_PREFIX[i].name) == 0)
+	    return BOOLEAN_PREFIX[i].prefix;
+
+    return "";
+}
+
+int TERM_COMBINED = 0;
+
+static void
+print_term (const char *prefix_name, const char *value)
+{
+    const char *prefix;
+
+    if (value == NULL)
+	return;
+
+    prefix = find_prefix (prefix_name);
+
+    if (TERM_COMBINED)
+	printf ("\"%s%s\", ", prefix, value);
+    else
+	printf ("[\"%s\", \"%s\"], ", value, prefix);
+}
+
+static void
+add_address_name (InternetAddress *address, const char *prefix_name)
+{
+    const char *name;
+
+    name = internet_address_get_name (address);
+
+    if (name)
+	print_term (prefix_name, name);
+}
+
+static void
+add_address_names (InternetAddressList *addresses, const char *address_type)
+{
+    int i;
+    InternetAddress *address;
+
+    for (i = 0; i < internet_address_list_length (addresses); i++) {
+	address = internet_address_list_get_address (addresses, i);
+	add_address_name (address, address_type);
+	add_address_name (address, "name");
+	add_address_name (address, "body");
+    }
+}
+
+static void
+add_address_addr (InternetAddress *address, const char *prefix_name)
+{
+    InternetAddressMailbox *mailbox = INTERNET_ADDRESS_MAILBOX (address);
+    const char *addr;
+
+    addr = internet_address_mailbox_get_addr (mailbox);
+
+    if (addr)
+	print_term (prefix_name, addr);
+}
+
+static void
+add_address_addrs (InternetAddressList *addresses, const char *address_type)
+{
+    int i;
+    InternetAddress *address;
+
+    for (i = 0; i < internet_address_list_length (addresses); i++) {
+	address = internet_address_list_get_address (addresses, i);
+	add_address_addr (address, address_type);
+	add_address_addr (address, "email");
+    }
 }
 
 int
@@ -41,22 +151,18 @@ main (int argc, char **argv)
     GMimeStream *stream;
     GMimeParser *parser;
     GMimeMessage *message;
+    InternetAddressList *addresses;
 
     const char *filename;
     FILE *file;
 
-    const char *sup_entry_headers[] = {
-	"From",
-	"Subject",
-	"Date",
-	"References",
-	"CC",
-	"To",
-	"In-Reply-To"
-    };
-    const char *value;
+    const char *value, *from;
     int i;
 
+    time_t time;
+    struct tm gm_time_tm;
+    char time_str[16]; /* YYYYMMDDHHMMSS + 1 for Y100k compatibility ;-) */
+
     if (argc < 2) {
 	fprintf (stderr, "Usage: %s <mail-message>\n",
 		 argv[0]);
@@ -79,15 +185,57 @@ main (int argc, char **argv)
 
     message = g_mime_parser_construct_message (parser);
 
-    value = g_mime_message_get_message_id (message);
-    print_header ("message_id", value);
+    printf ("text is:\n[");
+    from = g_mime_message_get_sender (message);
+    addresses = internet_address_list_parse_string (from);
 
-    for (i = 0; i < ARRAY_SIZE (sup_entry_headers); i++) {
-	value = g_mime_object_get_header (GMIME_OBJECT (message),
-					  sup_entry_headers[i]);
-	print_header (sup_entry_headers[i], value);
+    add_address_names (addresses, "from_name");
+
+    add_address_names (g_mime_message_get_all_recipients (message),
+		       "to_name");
+
+    value = g_mime_message_get_subject (message);
+    print_term ("subject", value);
+    print_term ("body", value);
+
+    printf ("]\nterms is:\n[");
+
+    TERM_COMBINED = 1;
+
+    from = g_mime_message_get_sender (message);
+    addresses = internet_address_list_parse_string (from);
+
+    add_address_addrs (addresses, "from_email");
+
+    add_address_addrs (g_mime_message_get_all_recipients (message),
+		       "to_email");
+
+    g_mime_message_get_date (message, &time, NULL);
+
+    gmtime_r (&time, &gm_time_tm);
+
+    if (strftime (time_str, sizeof (time_str),
+		  "%Y%m%d%H%M%S", &gm_time_tm) == 0) {
+	fprintf (stderr, "Internal error formatting time\n");
+	exit (1);
     }
 
+    print_term ("date", time_str);
+
+    print_term ("label", "inbox");
+    print_term ("label", "unread");
+    print_term ("type", "mail");
+
+    value = g_mime_message_get_message_id (message);
+    print_term ("msgid", value);
+
+    print_term ("source_id", "1");
+
+    value = g_mime_message_get_message_id (message);
+    print_term ("thread", value);
+
+    printf ("]\n");
+
     g_object_unref (message);
     g_object_unref (parser);
     g_object_unref (stream);