From d65ff0057f77e3d7d0aed9dd78196248b526f9b2 Mon Sep 17 00:00:00 2001
From: Carl Worth <cworth@cworth.org>
Date: Fri, 3 Aug 2007 22:44:13 -0700
Subject: [PATCH] Allow "/h <category> <length>" for histograms of words of a
 particular length

---
 mnemon.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 68 insertions(+), 12 deletions(-)

diff --git a/mnemon.c b/mnemon.c
index 446d449..7123464 100644
--- a/mnemon.c
+++ b/mnemon.c
@@ -115,7 +115,21 @@ xstrdup (const char *s)
     char *ret;
 
     ret = strdup (s);
-    if (s == NULL) {
+    if (ret == NULL) {
+	fprintf (stderr, "Error: out of memory\n");
+	exit (1);
+    }
+
+    return ret;
+}
+
+static char *
+xstrndup (const char *s, size_t n)
+{
+    char *ret;
+
+    ret = strndup (s, n);
+    if (ret == NULL) {
 	fprintf (stderr, "Error: out of memory\n");
 	exit (1);
     }
@@ -797,6 +811,27 @@ mnemon_item_in_category (void *closure, item_t *item)
     return (mnemon_item_category (mnemon, item) == category);
 }
 
+typedef struct _item_in_category_of_length_closure
+{
+    mnemon_t *mnemon;
+    category_t *category;
+    int length;
+} item_in_category_of_length_closure_t;
+
+static int
+mnemon_item_in_category_of_length (void *closure, item_t *item)
+{
+    item_in_category_of_length_closure_t *iicolc = closure;
+    mnemon_t *mnemon = iicolc->mnemon;
+    category_t *category = iicolc->category;
+    int length = iicolc->length;
+
+    if (mnemon_item_category (mnemon, item) != category)
+	return 0;
+
+    return strlen (item->challenge) == length;
+}
+
 static void
 mnemon_select_item (mnemon_t	 *mnemon,
 		    bin_t	**bin_ret,
@@ -873,7 +908,8 @@ print_histogram_bar (double	size,
 
 static void
 mnemon_print_histogram (mnemon_t    *mnemon,
-			const char  *category_name)
+			const char  *category_name,
+			int	     length)
 {
     int i, last_score, max;
     category_t *category = NULL;
@@ -882,6 +918,7 @@ mnemon_print_histogram (mnemon_t    *mnemon,
     item_match_predicate_t *predicate = NULL;
     void *closure = NULL;
     item_in_category_closure_t item_in_category;
+    item_in_category_of_length_closure_t item_in_category_of_length;
 
     if (mnemon->num_bins == 0)
 	return;
@@ -889,10 +926,18 @@ mnemon_print_histogram (mnemon_t    *mnemon,
     if (category_name) {
 	category = mnemon_get_category_if_exists (mnemon, category_name);
 	if (category) {
-	    predicate = mnemon_item_in_category;
-	    item_in_category.mnemon = mnemon;
-	    item_in_category.category = category;
-	    closure = &item_in_category;
+	    if (length) {
+		predicate = mnemon_item_in_category_of_length;
+		item_in_category_of_length.mnemon = mnemon;
+		item_in_category_of_length.category = category;
+		item_in_category_of_length.length = length;
+		closure = &item_in_category_of_length;
+	    } else {
+		predicate = mnemon_item_in_category;
+		item_in_category.mnemon = mnemon;
+		item_in_category.category = category;
+		closure = &item_in_category;
+	    }
 	}
     }
 
@@ -921,15 +966,26 @@ mnemon_handle_command (mnemon_t		*mnemon,
 		       const char	*command)
 {
     const char *arg;
+    int len;
     switch (command[0]) {
 	case 'h':
+	{
+	    char *category = NULL;
+	    int length = 0;
+
 	    arg = command + 1;
-	    while (*arg && isspace (*arg))
-		arg++;
-	    if (*arg == '\0')
-		arg = NULL;
-	    mnemon_print_histogram (mnemon, arg);
-	    break;
+	    arg += strspn (arg, " \t");
+	    len = strcspn (arg, " \t");
+	    if (len) {
+		category = xstrndup (arg, len);
+		arg += len;
+		arg += strspn (arg, " \t");
+		if (*arg)
+		    length = atoi (arg);
+	    }
+	    mnemon_print_histogram (mnemon, category, length);
+	}
+	break;
         default:
 	    printf ("Unknown command: %s\n", command);
 	    break;
-- 
2.43.0