[Evolution-hackers] Fix for "agressive" memory segmentation

[Philip Van Hoof <spam pvanhoof be>]

Camel makes some "aggressive" memory segmentation happen when loading
the folder summary.

This fixes that.

This is NOT yet the mmap() idea. That will come later.


-- 
Philip Van Hoof, software developer at x-tend 
home: me at pvanhoof dot be 
gnome: pvanhoof at gnome dot org 
work: vanhoof at x-tend dot be 
http://www.pvanhoof.be - http://www.x-tend.be

Index: camel-folder-summary.c
===================================================================
RCS file: /cvs/gnome/evolution-data-server/camel/camel-folder-summary.c,v
retrieving revision 1.148
diff -u -r1.148 camel-folder-summary.c
--- camel-folder-summary.c	12 Apr 2006 19:14:13 -0000	1.148
+++ camel-folder-summary.c	6 Jul 2006 18:28:30 -0000
@@ -1625,17 +1625,19 @@
 	if (ct)
 		camel_content_type_unref(ct);
 
-	mi->subject = camel_pstring_strdup(subject);
-	mi->from = camel_pstring_strdup(from);
-	mi->to = camel_pstring_strdup(to);
-	mi->cc = camel_pstring_strdup(cc);
-	mi->mlist = camel_pstring_strdup(mlist);
+	mi->subject = camel_pstring_strdup_or_reuse (subject);
+	mi->from = camel_pstring_strdup_or_reuse (from);
+	mi->to = camel_pstring_strdup_or_reuse(to);
+	mi->cc = camel_pstring_strdup_or_reuse(cc);
+	mi->mlist = camel_pstring_strdup_or_reuse(mlist);
 
+/*
 	g_free(subject);
 	g_free(from);
 	g_free(to);
 	g_free(cc);
 	g_free(mlist);
+*/
 
 	mi->user_flags = NULL;
 	mi->user_tags = NULL;
@@ -1711,18 +1713,19 @@
 	camel_file_util_decode_string(in, &mlist);
 
 	mi->uid = uid;
-	mi->subject = camel_pstring_strdup(subject);
-	mi->from = camel_pstring_strdup(from);
-	mi->to = camel_pstring_strdup(to);
-	mi->cc = camel_pstring_strdup(cc);
-	mi->mlist = camel_pstring_strdup(mlist);
+	mi->subject = camel_pstring_strdup_or_reuse (subject);
+	mi->from = camel_pstring_strdup_or_reuse (from);
+	mi->to = camel_pstring_strdup_or_reuse (to);
+	mi->cc = camel_pstring_strdup_or_reuse (cc);
+	mi->mlist = camel_pstring_strdup_or_reuse (mlist);
 
+/*
 	g_free(subject);
 	g_free(from);
 	g_free(to);
 	g_free(cc);
 	g_free(mlist);
-
+*/
 	mi->content = NULL;
 
 	camel_file_util_decode_fixed_int32(in, &mi->message_id.id.part.hi);
Index: camel-string-utils.c
===================================================================
RCS file: /cvs/gnome/evolution-data-server/camel/camel-string-utils.c,v
retrieving revision 1.5
diff -u -r1.5 camel-string-utils.c
--- camel-string-utils.c	15 Sep 2005 17:35:45 -0000	1.5
+++ camel-string-utils.c	6 Jul 2006 18:28:31 -0000
@@ -186,6 +186,48 @@
 	return p;
 }
 
+
+
+/**
+ * camel_pstring_strdup_or_reuse:
+ * @s: String to copy.
+ * 
+ * Create a new pooled string entry for the string @s.  A pooled
+ * string is a table where common strings are uniquified to the same
+ * pointer value.  They are also refcounted, so freed when no longer
+ * in use.  In a thread-safe manner.
+ * 
+ * The NULL and empty strings are special cased to constant values.
+ *
+ * Return value: A pointer to an equivalent string of @s.  Use
+ * camel_pstring_free() when it is no longer needed.
+ **/
+const char *camel_pstring_strdup_or_reuse (const char *s)
+{
+	char *p;
+	void *pcount;
+	int count;
+
+	if (s == NULL)
+		return NULL;
+	if (s[0] == 0)
+		return "";
+
+	pthread_mutex_lock(&pstring_lock);
+	if (pstring_table == NULL)
+		pstring_table = g_hash_table_new(g_str_hash, g_str_equal);
+
+	if (g_hash_table_lookup_extended(pstring_table, s, (void **)&p, &pcount)) {
+		count = GPOINTER_TO_INT(pcount)+1;
+		g_hash_table_insert(pstring_table, p, GINT_TO_POINTER(count));
+		g_free (s);
+	} else {
+		p = s;
+		g_hash_table_insert(pstring_table, p, GINT_TO_POINTER(1));
+	}
+	pthread_mutex_unlock(&pstring_lock);
+	return p;
+}
 /**
  * camel_pstring_free:
  * @s: String to free.
Index: camel-string-utils.h
===================================================================
RCS file: /cvs/gnome/evolution-data-server/camel/camel-string-utils.h,v
retrieving revision 1.5
diff -u -r1.5 camel-string-utils.h
--- camel-string-utils.h	31 Aug 2005 04:21:56 -0000	1.5
+++ camel-string-utils.h	6 Jul 2006 18:28:31 -0000
@@ -43,6 +43,8 @@
 char camel_toupper(char c);
 
 const char *camel_pstring_strdup(const char *s);
+const char *camel_pstring_strdup_or_reuse (const char *s);
+
 void camel_pstring_free(const char *s);
 
 #ifdef __cplusplus