X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fdata%2Fcasewindow.c;h=9b04b9413c61bbace1e5b189d68e65eebe152482;hb=edf539fc797fedcdf7a71894f707d3c9728335d6;hp=71a7c1bd2fe87aa6d6127622e9803510df1367ed;hpb=5aa037d0c36fcaf2a1ad3995bffe5c32fd201124;p=pspp-builds.git

diff --git a/src/data/casewindow.c b/src/data/casewindow.c
index 71a7c1bd..9b04b941 100644
--- a/src/data/casewindow.c
+++ b/src/data/casewindow.c
@@ -1,20 +1,18 @@
-/* PSPP - computes sample statistics.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+/* PSPP - a program for statistical analysis.
+   Copyright (C) 2007, 2009 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public License as
-   published by the Free Software Foundation; either version 2 of the
-   License, or (at your option) any later version.
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
 
-   This program is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301, USA. */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
 /* This casewindow implementation in terms of an class interface
    is undoubtedly a form of over-abstraction.  However, it works
@@ -35,26 +33,26 @@
 #include "xalloc.h"
 
 /* A queue of cases. */
-struct casewindow 
+struct casewindow
   {
     /* Common data. */
-    size_t value_cnt;             /* Number of values per case. */
+    struct caseproto *proto;      /* Prototype of cases in window. */
     casenumber max_in_core_cases; /* Max cases before dumping to disk. */
     struct taint *taint;          /* Taint status. */
 
     /* Implementation data. */
-    const struct casewindow_class *class; 
+    const struct casewindow_class *class;
     void *aux;
   };
 
 /* Implementation of a casewindow. */
-struct casewindow_class 
+struct casewindow_class
   {
-    void *(*create) (struct taint *, size_t value_cnt);
+    void *(*create) (struct taint *, const struct caseproto *);
     void (*destroy) (void *aux);
     void (*push_head) (void *aux, struct ccase *);
     void (*pop_tail) (void *aux, casenumber cnt);
-    bool (*get_case) (void *aux, casenumber ofs, struct ccase *);
+    struct ccase *(*get_case) (void *aux, casenumber ofs);
     casenumber (*get_case_cnt) (const void *aux);
   };
 
@@ -65,41 +63,44 @@ static const struct casewindow_class casewindow_file_class;
 /* Creates and returns a new casewindow using the given
    parameters. */
 static struct casewindow *
-do_casewindow_create (struct taint *taint,
-                      size_t value_cnt, casenumber max_in_core_cases) 
+do_casewindow_create (struct taint *taint, const struct caseproto *proto,
+                      casenumber max_in_core_cases)
 {
   struct casewindow *cw = xmalloc (sizeof *cw);
   cw->class = (max_in_core_cases
               ? &casewindow_memory_class
               : &casewindow_file_class);
-  cw->aux = cw->class->create (taint, value_cnt);
-  cw->value_cnt = value_cnt;
+  cw->aux = cw->class->create (taint, proto);
+  cw->proto = caseproto_ref (proto);
   cw->max_in_core_cases = max_in_core_cases;
   cw->taint = taint;
   return cw;
 }
 
-/* Creates and returns a new casewindow for cases with VALUE_CNT
-   values each.  If the casewindow holds more than
+/* Creates and returns a new casewindow for cases that take the
+   form specified by PROTO.  If the casewindow holds more than
    MAX_IN_CORE_CASES cases at any time, its cases will be dumped
-   to disk; otherwise, its cases will be held in memory. */   
+   to disk; otherwise, its cases will be held in memory.
+
+   The caller retains its reference to PROTO. */
 struct casewindow *
-casewindow_create (size_t value_cnt, casenumber max_in_core_cases) 
+casewindow_create (const struct caseproto *proto, casenumber max_in_core_cases)
 {
-  return do_casewindow_create (taint_create (), value_cnt, max_in_core_cases);
+  return do_casewindow_create (taint_create (), proto, max_in_core_cases);
 }
 
 /* Destroys casewindow CW.
    Returns true if CW was tainted, which is caused by an I/O
    error or by taint propagation to the casewindow. */
 bool
-casewindow_destroy (struct casewindow *cw) 
+casewindow_destroy (struct casewindow *cw)
 {
   bool ok = true;
-  if (cw != NULL) 
+  if (cw != NULL)
     {
       cw->class->destroy (cw->aux);
       ok = taint_destroy (cw->taint);
+      caseproto_unref (cw->proto);
       free (cw);
     }
   return ok;
@@ -107,7 +108,7 @@ casewindow_destroy (struct casewindow *cw)
 
 /* Swaps the contents of casewindows A and B. */
 static void
-casewindow_swap (struct casewindow *a, struct casewindow *b) 
+casewindow_swap (struct casewindow *a, struct casewindow *b)
 {
   struct casewindow tmp = *a;
   *a = *b;
@@ -116,17 +117,17 @@ casewindow_swap (struct casewindow *a, struct casewindow *b)
 
 /* Dumps the contents of casewindow OLD to disk. */
 static void
-casewindow_to_disk (struct casewindow *old) 
+casewindow_to_disk (struct casewindow *old)
 {
   struct casewindow *new;
-  new = do_casewindow_create (taint_clone (old->taint), old->value_cnt, 0);
+  new = do_casewindow_create (taint_clone (old->taint), old->proto, 0);
   while (casewindow_get_case_cnt (old) > 0 && !casewindow_error (new))
     {
-      struct ccase c;
-      if (!casewindow_get_case (old, 0, &c))
+      struct ccase *c = casewindow_get_case (old, 0);
+      if (c == NULL)
         break;
       casewindow_pop_tail (old, 1);
-      casewindow_push_head (new, &c);
+      casewindow_push_head (new, c);
     }
   casewindow_swap (old, new);
   casewindow_destroy (new);
@@ -135,7 +136,7 @@ casewindow_to_disk (struct casewindow *old)
 /* Pushes case C at the head of casewindow CW.
    Case C becomes owned by the casewindow. */
 void
-casewindow_push_head (struct casewindow *cw, struct ccase *c) 
+casewindow_push_head (struct casewindow *cw, struct ccase *c)
 {
   if (!casewindow_error (cw))
     {
@@ -145,86 +146,84 @@ casewindow_push_head (struct casewindow *cw, struct ccase *c)
           casenumber case_cnt = cw->class->get_case_cnt (cw->aux);
           if (case_cnt > cw->max_in_core_cases
               && cw->class == &casewindow_memory_class)
-            casewindow_to_disk (cw); 
+            casewindow_to_disk (cw);
         }
     }
   else
-    case_destroy (c);
+    case_unref (c);
 }
 
 /* Deletes CASE_CNT cases at the tail of casewindow CW. */
 void
-casewindow_pop_tail (struct casewindow *cw, casenumber case_cnt) 
+casewindow_pop_tail (struct casewindow *cw, casenumber case_cnt)
 {
-  if (!casewindow_error (cw)) 
+  if (!casewindow_error (cw))
     cw->class->pop_tail (cw->aux, case_cnt);
 }
 
-/* Copies the case that is CASE_IDX cases away from CW's tail
-   into C.  Returns true if successful, false on an I/O error or
-   if CW is otherwise tainted.  On failure, nullifies case C. */
-bool
-casewindow_get_case (const struct casewindow *cw_, casenumber case_idx,
-                     struct ccase *c) 
+/* Returns the case that is CASE_IDX cases away from CW's tail
+   into C, or a null pointer on an I/O error or if CW is
+   otherwise tainted.  The caller must call case_unref() on the
+   returned case when it is no longer needed. */
+struct ccase *
+casewindow_get_case (const struct casewindow *cw_, casenumber case_idx)
 {
   struct casewindow *cw = (struct casewindow *) cw_;
 
   assert (case_idx >= 0 && case_idx < casewindow_get_case_cnt (cw));
-  if (!casewindow_error (cw))
-    return cw->class->get_case (cw->aux, case_idx, c);
-  else 
-    {
-      case_nullify (c);
-      return false;
-    }
+  if (casewindow_error (cw))
+    return NULL;
+  return cw->class->get_case (cw->aux, case_idx);
 }
 
 /* Returns the number of cases in casewindow CW. */
 casenumber
-casewindow_get_case_cnt (const struct casewindow *cw) 
+casewindow_get_case_cnt (const struct casewindow *cw)
 {
   return cw->class->get_case_cnt (cw->aux);
 }
 
-/* Returns the number of values per case in casewindow CW. */
-size_t
-casewindow_get_value_cnt (const struct casewindow *cw) 
+/* Returns the case prototype for the cases in casewindow CW.
+   The caller must not unref the returned prototype. */
+const struct caseproto *
+casewindow_get_proto (const struct casewindow *cw)
 {
-  return cw->value_cnt;
+  return cw->proto;
 }
 
 /* Returns true if casewindow CW is tainted.
    A casewindow is tainted by an I/O error or by taint
    propagation to the casewindow. */
 bool
-casewindow_error (const struct casewindow *cw) 
+casewindow_error (const struct casewindow *cw)
 {
   return taint_is_tainted (cw->taint);
 }
 
 /* Marks casewindow CW tainted. */
 void
-casewindow_force_error (struct casewindow *cw) 
+casewindow_force_error (struct casewindow *cw)
 {
   taint_set_taint (cw->taint);
 }
 
 /* Returns casewindow CW's taint object. */
 const struct taint *
-casewindow_get_taint (const struct casewindow *cw) 
+casewindow_get_taint (const struct casewindow *cw)
 {
   return cw->taint;
 }
 
 /* In-memory casewindow data. */
-struct casewindow_memory 
+struct casewindow_memory
   {
     struct deque deque;
-    struct ccase *cases;
+    struct ccase **cases;
   };
 
 static void *
-casewindow_memory_create (struct taint *taint UNUSED, size_t value_cnt UNUSED) 
+casewindow_memory_create (struct taint *taint UNUSED,
+                          const struct caseproto *proto UNUSED)
 {
   struct casewindow_memory *cwm = xmalloc (sizeof *cwm);
   cwm->cases = deque_init (&cwm->deque, 4, sizeof *cwm->cases);
@@ -232,11 +231,11 @@ casewindow_memory_create (struct taint *taint UNUSED, size_t value_cnt UNUSED)
 }
 
 static void
-casewindow_memory_destroy (void *cwm_) 
+casewindow_memory_destroy (void *cwm_)
 {
   struct casewindow_memory *cwm = cwm_;
-  while (!deque_is_empty (&cwm->deque)) 
-    case_destroy (&cwm->cases[deque_pop_front (&cwm->deque)]);
+  while (!deque_is_empty (&cwm->deque))
+    case_unref (cwm->cases[deque_pop_front (&cwm->deque)]);
   free (cwm->cases);
   free (cwm);
 }
@@ -247,7 +246,7 @@ casewindow_memory_push_head (void *cwm_, struct ccase *c)
   struct casewindow_memory *cwm = cwm_;
   if (deque_is_full (&cwm->deque))
     cwm->cases = deque_expand (&cwm->deque, cwm->cases, sizeof *cwm->cases);
-  case_move (&cwm->cases[deque_push_back (&cwm->deque)], c);
+  cwm->cases[deque_push_back (&cwm->deque)] = c;
 }
 
 static void
@@ -255,26 +254,25 @@ casewindow_memory_pop_tail (void *cwm_, casenumber case_cnt)
 {
   struct casewindow_memory *cwm = cwm_;
   assert (deque_count (&cwm->deque) >= case_cnt);
-  while (case_cnt-- > 0) 
-    case_destroy (&cwm->cases[deque_pop_front (&cwm->deque)]);
+  while (case_cnt-- > 0)
+    case_unref (cwm->cases[deque_pop_front (&cwm->deque)]);
 }
 
-static bool
-casewindow_memory_get_case (void *cwm_, casenumber ofs, struct ccase *c) 
+static struct ccase *
+casewindow_memory_get_case (void *cwm_, casenumber ofs)
 {
   struct casewindow_memory *cwm = cwm_;
-  case_clone (c, &cwm->cases[deque_front (&cwm->deque, ofs)]);
-  return true;
+  return case_ref (cwm->cases[deque_front (&cwm->deque, ofs)]);
 }
 
 static casenumber
-casewindow_memory_get_case_cnt (const void *cwm_) 
+casewindow_memory_get_case_cnt (const void *cwm_)
 {
   const struct casewindow_memory *cwm = cwm_;
   return deque_count (&cwm->deque);
 }
 
-static const struct casewindow_class casewindow_memory_class = 
+static const struct casewindow_class casewindow_memory_class =
   {
     casewindow_memory_create,
     casewindow_memory_destroy,
@@ -285,24 +283,24 @@ static const struct casewindow_class casewindow_memory_class =
   };
 
 /* On-disk casewindow data. */
-struct casewindow_file 
+struct casewindow_file
   {
     struct case_tmpfile *file;
     casenumber head, tail;
   };
 
 static void *
-casewindow_file_create (struct taint *taint, size_t value_cnt) 
+casewindow_file_create (struct taint *taint, const struct caseproto *proto)
 {
   struct casewindow_file *cwf = xmalloc (sizeof *cwf);
-  cwf->file = case_tmpfile_create (value_cnt);
+  cwf->file = case_tmpfile_create (proto);
   cwf->head = cwf->tail = 0;
   taint_propagate (case_tmpfile_get_taint (cwf->file), taint);
   return cwf;
 }
 
 static void
-casewindow_file_destroy (void *cwf_) 
+casewindow_file_destroy (void *cwf_)
 {
   struct casewindow_file *cwf = cwf_;
   case_tmpfile_destroy (cwf->file);
@@ -310,15 +308,15 @@ casewindow_file_destroy (void *cwf_)
 }
 
 static void
-casewindow_file_push_head (void *cwf_, struct ccase *c) 
+casewindow_file_push_head (void *cwf_, struct ccase *c)
 {
   struct casewindow_file *cwf = cwf_;
-  if (case_tmpfile_put_case (cwf->file, cwf->head, c)) 
+  if (case_tmpfile_put_case (cwf->file, cwf->head, c))
     cwf->head++;
 }
 
 static void
-casewindow_file_pop_tail (void *cwf_, casenumber cnt) 
+casewindow_file_pop_tail (void *cwf_, casenumber cnt)
 {
   struct casewindow_file *cwf = cwf_;
   assert (cnt <= cwf->head - cwf->tail);
@@ -327,21 +325,21 @@ casewindow_file_pop_tail (void *cwf_, casenumber cnt)
     cwf->head = cwf->tail = 0;
 }
 
-static bool
-casewindow_file_get_case (void *cwf_, casenumber ofs, struct ccase *c) 
+static struct ccase *
+casewindow_file_get_case (void *cwf_, casenumber ofs)
 {
   struct casewindow_file *cwf = cwf_;
-  return case_tmpfile_get_case (cwf->file, cwf->tail + ofs, c);
+  return case_tmpfile_get_case (cwf->file, cwf->tail + ofs);
 }
 
 static casenumber
-casewindow_file_get_case_cnt (const void *cwf_) 
+casewindow_file_get_case_cnt (const void *cwf_)
 {
   const struct casewindow_file *cwf = cwf_;
   return cwf->head - cwf->tail;
 }
 
-static const struct casewindow_class casewindow_file_class = 
+static const struct casewindow_class casewindow_file_class =
   {
     casewindow_file_create,
     casewindow_file_destroy,