X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Futil.c;h=d292634731b662827dc8c0dfbeec0f566ab5a32a;hb=8ab9f6acce5bbc6e56d2f3fa1833be06faf46770;hp=3ac6596808bafd865a7a8c7adb97b588c7ea8997;hpb=ebdb5ef23b8e152a4793d5927b5d92d7e7b2cc4f;p=bluesky.git

diff --git a/bluesky/util.c b/bluesky/util.c
index 3ac6596..d292634 100644
--- a/bluesky/util.c
+++ b/bluesky/util.c
@@ -10,6 +10,7 @@
 #include <stdint.h>
 #include <glib.h>
 #include <string.h>
+#include <sys/mman.h>
 
 #include "bluesky-private.h"
 
@@ -59,6 +60,7 @@ gboolean bluesky_inode_is_ready(BlueSkyInode *inode)
 BlueSkyRCStr *bluesky_string_new(gpointer data, gsize len)
 {
     BlueSkyRCStr *string = g_new(BlueSkyRCStr, 1);
+    string->mmap = NULL;
     string->data = data;
     string->len = len;
     g_atomic_int_set(&string->refcount, 1);
@@ -72,6 +74,21 @@ BlueSkyRCStr *bluesky_string_new_from_gstring(GString *s)
     return bluesky_string_new(g_string_free(s, FALSE), len);
 }
 
+/* Create a new BlueSkyRCStr from a memory-mapped buffer. */
+BlueSkyRCStr *bluesky_string_new_from_mmap(BlueSkyCacheFile *mmap,
+                                           int offset, gsize len)
+{
+    g_assert(offset + len <= mmap->len);
+
+    BlueSkyRCStr *string = g_new(BlueSkyRCStr, 1);
+    string->mmap = mmap;
+    g_atomic_int_inc(&mmap->mapcount);
+    string->data = (char *)mmap->addr + offset;
+    string->len = len;
+    g_atomic_int_set(&string->refcount, 1);
+    return string;
+}
+
 void bluesky_string_ref(BlueSkyRCStr *string)
 {
     if (string == NULL)
@@ -86,7 +103,11 @@ void bluesky_string_unref(BlueSkyRCStr *string)
         return;
 
     if (g_atomic_int_dec_and_test(&string->refcount)) {
-        g_free(string->data);
+        if (string->mmap == NULL) {
+            g_free(string->data);
+        } else {
+            bluesky_mmap_unref(string->mmap);
+        }
         g_free(string);
     }
 }
@@ -102,6 +123,14 @@ BlueSkyRCStr *bluesky_string_dup(BlueSkyRCStr *string)
     if (string == NULL)
         return NULL;
 
+    if (string->mmap != NULL) {
+        BlueSkyRCStr *s;
+        s = bluesky_string_new(g_memdup(string->data, string->len),
+                               string->len);
+        bluesky_string_unref(string);
+        return s;
+    }
+
     if (g_atomic_int_dec_and_test(&string->refcount)) {
         /* There are no other shared copies, so return this one. */
         g_atomic_int_inc(&string->refcount);
@@ -119,6 +148,8 @@ BlueSkyRCStr *bluesky_string_dup(BlueSkyRCStr *string)
  * if needed). */
 void bluesky_string_resize(BlueSkyRCStr *string, gsize len)
 {
+    g_assert(string->mmap == NULL);
+
     if (string->len == len)
         return;