Add caching of UCS data

5 files changed, 200 insertions, 19 deletions

diff --git a/Makefile b/Makefile
index 72b295c..b4aec4f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 CC	     = cc
-CFLAGS	     = -g -O -I. -W -Wall
+CFLAGS	     = -g -O3 -I. -W -Wall -DHAVE_PTHREAD_H
 PICFLAGS     = -fPIC
-LDFLAGS      =
+LDFLAGS      = -lpthread
 AR           = ar
 RANLIB       = ranlib
 LIB_FILE     = libucd.a
@@ -18,6 +18,11 @@ PERL         = time perl
 
 
 #
+# Headers included from libucd_int.h
+#
+HDRS = libucd_int.h ucd.h int24.h compiler.h
+
+#
 # These are the files produced by convert_ucd.pl
 #
 CVT_FILES = gen/jamo.c gen/nameslist.tab gen/nametoucs.keys gen/nametoucs.tab \
@@ -48,7 +53,7 @@ CVT_FILES = gen/jamo.c gen/nameslist.tab gen/nametoucs.keys gen/nametoucs.tab \
 LIBSRCS = proparray.c gen/nametoucs_hash.c gen/ucstoname_hash.c \
 	  gen/jamo.c gen/nameslist.c gen/nameslist_dict.c \
 	  gen/ucstoname_tab.c gen/nametoucs_tab.c nametoucs.c \
-	  ucslookup.c
+	  ucslookup.c cache.c
 
 LIBOBJS = $(patsubst %.c,%.o,$(LIBSRCS))
 SO_OBJS = $(patsubst %.c,%.lo,$(LIBSRCS))
@@ -126,23 +131,26 @@ endif
 
 # -----------------------------------------------------------------------
 
-proparray.o: proparray.c ucd.h libucd_int.h gen/proparray.c
-proparray.lo: proparray.c ucd.h libucd_int.h gen/proparray.c
+proparray.o: proparray.c ucd.h $(HDRS) gen/proparray.c
+proparray.lo: proparray.c ucd.h $(HDRS) gen/proparray.c
 
 mk_ucstoname_tab.ho: mk_ucstoname_tab.c gen/ucstoname_hash.h
 mk_nametoucs_tab.ho: mk_nametoucs_tab.c gen/nametoucs_hash.h
 
-gen/ucstoname_tab.o: gen/ucstoname_tab.c libucd_int.h
-gen/ucstoname_tab.lo: gen/ucstoname_tab.c libucd_int.h
+gen/ucstoname_tab.o: gen/ucstoname_tab.c $(HDRS)
+gen/ucstoname_tab.lo: gen/ucstoname_tab.c $(HDRS)
 
-gen/nametoucs_tab.o: gen/nametoucs_tab.c libucd_int.h
-gen/nametoucs_tab.lo: gen/nametoucs_tab.c libucd_int.h
+gen/nametoucs_tab.o: gen/nametoucs_tab.c $(HDRS)
+gen/nametoucs_tab.lo: gen/nametoucs_tab.c $(HDRS)
 
 gen/nameslist_dict.o: gen/nameslist_dict.c
 gen/nameslist_dict.lo: gen/nameslist_dict.c
 
-nametoucs.o: nametoucs.c libucd_int.h gen/nametoucs_hash.h
-nametoucs.lo: nametoucs.c libucd_int.h gen/nametoucs_hash.h
+nametoucs.o: nametoucs.c $(HDRS) gen/nametoucs_hash.h
+nametoucs.lo: nametoucs.c $(HDRS) gen/nametoucs_hash.h
+
+ucslookup.o: ucslookup.c $(HDRS) gen/ucstoname_hash.h
+ucslookup.lo: ucslookup.c $(HDRS) gen/ucstoname_hash.h
 
-ucslookup.o: ucslookup.c libucd_int.h gen/ucstoname_hash.h
-ucslookup.lo: ucslookup.c libucd_int.h gen/ucstoname_hash.h
+cache.o: cache.c $(HDRS)
+cache.lo: cache.c $(HDRS)
diff --git a/cache.c b/cache.c
new file mode 100644
index 0000000..8ff7d10
--- /dev/null
+++ b/cache.c
@@ -0,0 +1,132 @@
+#include <stdlib.h>
+#include "libucd_int.h"
+#ifdef HAVE_PTHREAD_H
+# include <pthread.h>
+#endif
+
+#define CACHE_SIZE 512
+static struct unicode_character_data *_libucd_cache[CACHE_SIZE];
+
+#ifdef HAVE_PTHREAD_H
+static pthread_mutex_t _libucd_cache_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static void lock_cache(void)
+{
+  pthread_mutex_lock(&_libucd_cache_mutex);
+}
+static void unlock_cache(void)
+{
+  pthread_mutex_unlock(&_libucd_cache_mutex);
+}
+
+#else
+
+/* Single-threaded execution only */
+static void lock_cache(void)
+{
+}
+static void unlock_cache(void)
+{
+}
+#endif
+
+#if defined(HAVE_PTHREAD_H) && (defined(__i386__) || defined(__x86_64__))
+
+/* Specially optimized versions for i386 and x86-64 */
+
+struct unicode_character_data *
+unicode_character_get(struct unicode_character_data *ucd)
+{
+  struct libucd_private *pvt = (struct libucd_private *)(ucd+1);
+  asm volatile("lock ; incl %0" : "+m" (pvt->usage_ctr));
+  return ucd;
+}
+
+void
+unicode_character_put(struct unicode_character_data *ucd)
+{
+  struct libucd_private *pvt = (struct libucd_private *)(ucd+1);
+  unsigned char zero;
+  
+  asm volatile("lock ; decl %0 ; setz %1"
+	       : "+m" (pvt->usage_ctr), "=r" (zero));
+  if ( zero )
+    free(ucd);
+}
+
+#else
+
+# ifdef HAVE_PTHREAD_H
+static void lock(struct libucd_private *pvt)
+{
+  pthread_mutex_lock(&pvt->mutex);
+}
+static void unlock(struct libucd_private *pvt)
+{
+  pthread_mutex_unlock(&pvt->mutex);
+}
+# else
+static void lock(struct libucd_private *pvt)
+{
+}
+static void unlock(struct libucd_private *pvt)
+{
+}
+# endif
+
+struct unicode_character_data *
+unicode_character_get(struct unicode_character_data *ucd)
+{
+  struct libucd_private *pvt = (struct libucd_private *)(ucd+1);
+  lock(pvt);
+  pvt->usage_ctr++;
+  unlock(pvt);
+  return ucd;
+}
+
+void
+unicode_character_put(struct unicode_character_data *ucd)
+{
+  struct libucd_private *pvt = (struct libucd_private *)(ucd+1);
+  unsigned int cnt;
+  lock(pvt);
+  cnt = --pvt->usage_ctr;
+  unlock(pvt);
+  if ( !cnt )
+    free(ucd);
+}
+
+#endif
+
+struct unicode_character_data *
+unicode_character_data(int32_t ucs)
+{
+  struct unicode_character_data *ucd, *prev_ucd;
+  unsigned int bucket;
+  
+  if ( ucs < 0 || ucs > 0x10ffff )
+    return NULL;
+
+  bucket = (uint32_t)ucs % CACHE_SIZE;
+
+  lock_cache();
+  ucd = _libucd_cache[bucket];
+  if ( ucd && ucd->ucs == ucs ) {
+    ucd = unicode_character_get(ucd);
+    unlock_cache();
+    return ucd;
+  }
+  unlock_cache();
+
+  ucd = unicode_character_data_raw(ucs);
+  
+  lock_cache();
+  prev_ucd = _libucd_cache[bucket];
+  _libucd_cache[bucket] = ucd;
+  unlock_cache();
+
+  if ( prev_ucd )
+    unicode_character_put(prev_ucd);
+  
+  return ucd;
+}
diff --git a/libucd_int.h b/libucd_int.h
index 955607b..5514ac0 100644
--- a/libucd_int.h
+++ b/libucd_int.h
@@ -62,4 +62,19 @@ extern const struct _libucd_nametoucs_tab _libucd_nametoucs_tab[];
 extern const unsigned char _libucd_names_list[];
 extern const char * const _libucd_nameslist_dict[256];
 
+/* This is a private data structure included in each ucd object */
+#if defined(__i386__) || defined(__x86_64__)
+# define HAVE_ATOMIC_CTR
+#endif
+
+struct libucd_private {
+#if defined(HAVE_PTHREAD_H) && !defined(HAVE_ATOMIC_CTR)
+  pthread_mutex_t mutex;
+#endif
+  volatile unsigned int usage_ctr;
+};
+
+struct unicode_character_data *
+unicode_character_data_raw(int32_t ucs);
+
 #endif
diff --git a/ucd.h b/ucd.h
index ebbc8f4..c205c47 100644
--- a/ucd.h
+++ b/ucd.h
@@ -36,6 +36,12 @@
 
 #include <stdint.h>
 
+#define LIBUCD_THREAD_SUPPORT
+
+#ifdef LIBUCD_THREAD_SUPPORT
+# include <pthread.h>
+#endif
+
 enum unicode_bidi_class {
   UC_BIDI_AL,			/* Arabic_Letter */
   UC_BIDI_AN,			/* Arabic_Number */
@@ -540,13 +546,15 @@ enum unicode_block {
 #define UC_FL_BIDI_MIRRORED		UC_FLAG(35)
 
 struct unicode_character_data {
+  int32_t ucs;			/* Actual codepoint */
+  uint16_t size;		/* Size of this structure */
+  uint16_t alloc_size;		/* Allocation size */
   uint64_t fl;			/* Flags */
   const char *name;
   const char *bidi_mirroring_glyph;
   const char *uppercase_mapping;
   const char *lowercase_mapping;
   const char *titlecase_mapping;
-  int32_t ucs;			/* Actual codepoint */
   int32_t simple_uppercase;
   int32_t simple_lowercase;
   int32_t simple_titlecase;
@@ -572,5 +580,7 @@ struct unicode_character_data {
 };
 
 struct unicode_character_data *unicode_character_data(int32_t);
+struct unicode_character_data *unicode_character_get(struct unicode_character_data *);
+void unicode_character_put(struct unicode_character_data *);
 
 #endif /* UCD_H */
diff --git a/ucslookup.c b/ucslookup.c
index 3192080..3283b0b 100644
--- a/ucslookup.c
+++ b/ucslookup.c
@@ -6,6 +6,9 @@
 #include <errno.h>
 #include "libucd_int.h"
 #include "gen/ucstoname_hash.h"
+#ifdef HAVE_PTHREAD_H
+# include <pthread.h>
+#endif
 
 /*
  * This returns the name for a specific UCS in a user-provided buffer,
@@ -98,11 +101,18 @@ alloc_copy_properties(const struct _libucd_property_array *prop,
 		      int32_t ucs, size_t namelen)
 {
   struct unicode_character_data *ucd;
+  struct libucd_private *pvt;
+  size_t size = sizeof(struct unicode_character_data)+
+    sizeof(struct libucd_private)+namelen+1;
 
-  ucd = malloc(sizeof(struct unicode_character_data)+namelen+1);
+
+  ucd = malloc(size);
   if ( !ucd )
     return NULL;
-  ucd->name = (char *)(ucd+1);
+  pvt = (struct libucd_private *)(ucd+1);
+  ucd->name = (char *)(pvt+1);
+  ucd->size = sizeof(struct unicode_character_data);
+  ucd->alloc_size = size;
 
   ucd->fl = prop->flags_block & UINT64_C(0xffffffffffff);
   ucd->bidi_mirroring_glyph = NULL; /* NYS */
@@ -138,6 +148,14 @@ alloc_copy_properties(const struct _libucd_property_array *prop,
   ucd->word_break = prop->word_break;
   ucd->line_break = prop->line_break;
 
+#if defined(HAVE_PTHREAD_H) && !defined(HAVE_ATOMIC_CTR)
+  if ( pthread_mutex_init(&pvt->mutex, NULL) ) {
+    free(ucd);
+    return NULL;
+  }
+#endif
+  pvt->usage_ctr = 2;		/* cache plus end user */
+
   return ucd;
 }
 
@@ -145,7 +163,7 @@ alloc_copy_properties(const struct _libucd_property_array *prop,
  * Standard entry point for the user
  */
 struct unicode_character_data *
-unicode_character_data(int32_t ucs)
+unicode_character_data_raw(int32_t ucs)
 {
   uint32_t hash;
   const struct _libucd_ucstoname_tab  *unt;
@@ -206,5 +224,3 @@ unicode_character_data(int32_t ucs)
 
   return ucd;
 }
-
-