# HG changeset patch
# User Adam Chlipala <adam@chlipala.net>
# Date 1447966924 18000
# Node ID 6e580e31907786fcea8bc3db656e831884297c3f
# Parent  6d56080f495c529eec8e8fdbae1935e2691b599e
Fix condition for installing new cache entries

diff -r 6d56080f495c -r 6e580e319077 src/c/urweb.c
--- a/src/c/urweb.c	Thu Nov 19 13:18:58 2015 -0500
+++ b/src/c/urweb.c	Thu Nov 19 16:02:04 2015 -0500
@@ -504,8 +504,8 @@
   size_t output_buffer_size;
 
   // Sqlcache.
-  int numRecording;
-  int recordingOffset;
+  int numRecording, recordingCapacity;
+  int *recordingOffsets;
   uw_Sqlcache_Update *cacheUpdate;
   uw_Sqlcache_Update *cacheUpdateTail;
   uw_Sqlcache_Unlock *cacheUnlock;
@@ -596,7 +596,8 @@
   ctx->output_buffer_size = 1;
 
   ctx->numRecording = 0;
-  ctx->recordingOffset = 0;
+  ctx->recordingCapacity = 0;
+  ctx->recordingOffsets = malloc(0);
   ctx->cacheUpdate = NULL;
   ctx->cacheUpdateTail = NULL;
 
@@ -669,6 +670,8 @@
 
   free(ctx->output_buffer);
 
+  free(ctx->recordingOffsets);
+
   free(ctx);
 }
 
@@ -692,6 +695,7 @@
   ctx->usedSig = 0;
   ctx->needsResig = 0;
   ctx->remoteSock = -1;
+  ctx->numRecording = 0;
 }
 
 void uw_reset_keep_request(uw_context ctx) {
@@ -1739,17 +1743,16 @@
 }
 
 void uw_recordingStart(uw_context ctx) {
-  if (ctx->numRecording++ == 0) {
-    ctx->recordingOffset = ctx->page.front - ctx->page.start;
+  if (ctx->numRecording == ctx->recordingCapacity) {
+    ++ctx->recordingCapacity;
+    ctx->recordingOffsets = realloc(ctx->recordingOffsets, sizeof(int) * ctx->recordingCapacity);
   }
+  ctx->recordingOffsets[ctx->numRecording] = ctx->page.front - ctx->page.start;
+  ++ctx->numRecording;
 }
 
 char *uw_recordingRead(uw_context ctx) {
-  // Only the outermost recorder can read unless the recording is empty.
-  char *recording = ctx->page.start + ctx->recordingOffset;
-  if (--ctx->numRecording > 0 && recording != ctx->page.front) {
-    return NULL;
-  }
+  char *recording = ctx->page.start + ctx->recordingOffsets[--ctx->numRecording];
   return strdup(recording);
 }
 
@@ -4709,6 +4712,7 @@
     while (numKeys-- > 0) {
       buf = uw_Sqlcache_keyCopy(buf, keys[numKeys]);
       size_t len = buf - key;
+      
       entry = uw_Sqlcache_find(cache, key, len, 1);
       if (!entry) {
         entry = calloc(1, sizeof(uw_Sqlcache_Entry));
@@ -4720,7 +4724,7 @@
     }
     free(key);
   }
-  if (entry->value && entry->value->timeValid < value->timeValid) {
+  if (!entry->value || entry->value->timeValid < value->timeValid) {
     uw_Sqlcache_freeValue(entry->value);
     entry->value = value;
     entry->value->timeValid = timeNow;
diff -r 6d56080f495c -r 6e580e319077 src/lru_cache.sml
--- a/src/lru_cache.sml	Thu Nov 19 13:18:58 2015 -0500
+++ b/src/lru_cache.sml	Thu Nov 19 16:02:04 2015 -0500
@@ -65,6 +65,7 @@
 
         val revArgs = paramRepeatRev (fn p => "p" ^ p) ", "
 
+        val argNums = List.tabulate (params, fn i => "p" ^ Int.toString i)
     in
         Print.box
             [string ("static uw_Sqlcache_Cache cacheStruct" ^ i ^ " = {"),
@@ -119,7 +120,12 @@
              newline,
              string "  } else {",
              newline,
-             (*string ("    puts(\"SQLCACHE: miss " ^ i ^ ".\");"),
+             (*string ("    printf(\"SQLCACHE: miss " ^ i ^ " " ^ String.concatWith ", " (List.tabulate (params, fn _ => "%s")) ^ ".\\n\""),
+             (case argNums of
+                  [] => Print.box []
+                 | _ => Print.box [string ", ",
+                                   p_list string argNums]),
+             string ");",
              newline,*)
              string "    uw_recordingStart(ctx);",
              newline,
@@ -159,6 +165,8 @@
              newline,
              string ("  uw_Sqlcache_flush(ctx, cache" ^ i ^ ", ks);"),
              newline,
+             (*string ("  puts(\"SQLCACHE: flushed " ^ i ^ ".\");"),
+             newline,*)
              string "  return uw_unit_v;",
              newline,
              string "}",
diff -r 6d56080f495c -r 6e580e319077 tests/fib.ur
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/fib.ur	Thu Nov 19 16:02:04 2015 -0500
@@ -0,0 +1,10 @@
+fun fib n =
+    if n = 0 then
+        0
+    else if n = 1 then
+        1
+    else
+        fib (n - 1) + fib (n - 2)
+
+fun main n : transaction page =
+    return <xml>{[fib n]}</xml>