If the base address doesn't match, try to map at the required base

address instead.

5 files changed, 22 insertions, 10 deletions

diff --git a/Makefile b/Makefile
index 3a73508..fbbd173 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 TEST     = teststore test_mmap ftrunctest testbuddy testalloc testrecovery
 SONAME   = libpsm.so.0
-VERSION  = 0.1.3
+VERSION  = 0.1.4
 LIBPSM	 = libpsm.so libpsm.a
 
 CFILES   = arena.c bitops.c \
diff --git a/README b/README
index 1d929ae..4d2aa35 100644
--- a/README
+++ b/README
@@ -54,7 +54,8 @@ The LPSM library installs a signal handler for SIGSEGV.
 
 * Functions to use in unmanaged mode:
 
-void *lpsm_arena_init(const char *datafile, const char *logfile, size_t *arena_size)
+void *lpsm_arena_init(const char *datafile, const char *logfile,
+                      size_t *arena_size, void *arena_base)
 
 	Open the persistent memory arena that consists of the two
 	files datafile and logfile.  If these files don't exist, they
@@ -64,6 +65,10 @@ void *lpsm_arena_init(const char *datafile, const char *logfile, size_t *arena_s
 
 	It returns a pointer to the arena, or NULL on error.
 
+	If arena_base is set, try to map the arena at that particular
+	base address.  If arena_base is NULL, use an
+	architecture-specific default value.
+
 
 pid_t lpsm_checkpoint(double ratio, enum psmsync wait)
 
diff --git a/arena.c b/arena.c
index f28cb45..0de97d9 100644
--- a/arena.c
+++ b/arena.c
@@ -285,15 +285,15 @@ static int lpsm_recover_log(void)
  * playback (crash recovery) if the log file exists
  * and is nonempty.
  */
-void *lpsm_arena_init(const char *main_file, const char *log_file, size_t *arena_len)
+void *lpsm_arena_init(const char *main_file, const char *log_file,
+		      size_t *arena_len, void *arena_ptr)
 {
-  void *arena_ptr;
   struct sigaction sigact;
   struct flock lock;
   off_t file_len, len = arena_len ? *arena_len : 0;
   size_t file_pages, len_pages;
 
-  arena_ptr = ARENA_ADDRESS;
+  arena_ptr = arena_ptr ? arena_ptr : ARENA_ADDRESS;
 
   PM = malloc(sizeof(struct lpsm_arena));
   if ( !PM )
diff --git a/lpsm.h b/lpsm.h
index 485d669..0af85bf 100644
--- a/lpsm.h
+++ b/lpsm.h
@@ -39,7 +39,7 @@ enum psmsync {
   PSMSYNC_SYNC			/* Wait until this writeback finishes */
 };
 
-void *lpsm_arena_init(const char *, const char *, size_t *);
+void *lpsm_arena_init(const char *, const char *, size_t *, void *);
 pid_t lpsm_checkpoint(double, enum psmsync);
 int lpsm_extend(size_t);
 void lpsm_shutdown(void);
diff --git a/mgmt.c b/mgmt.c
index c123d7d..956520a 100644
--- a/mgmt.c
+++ b/mgmt.c
@@ -59,11 +59,9 @@ void **lpsm_init(const char *main_file, const char *log_file)
 {
   size_t arena_len = sizeof(struct arena_header); /* Minimum initial size */
 
-  if ( !lpsm_arena_init(main_file, log_file, &arena_len) )
+  if ( !(AH = lpsm_arena_init(main_file, log_file, &arena_len, NULL)) )
     return NULL;		/* Failed to initialize arena */
 
-  AH = (struct arena_header *)PM->arena;
-
   if ( memcmp(AH->arena_magic, lpsm_arena_magic, 16) != 0 ) {
     if ( memcmp(AH->arena_magic, lpsm_arena_zero, 16) == 0 ) {
       size_t total_size, bitmap_size;
@@ -128,10 +126,19 @@ void **lpsm_init(const char *main_file, const char *log_file)
        AH->arena_byteorder != 0x12345678 ||
        AH->arena_bytesize  != CHAR_BIT   ||
        AH->arena_ptrsize   != sizeof(void *) ||
-       AH->arena_base      != (void *)AH ||
        AH->buddy_order_min != BUDDY_ORDER_MIN ) {
     return NULL;		/* Incompatible or corrupt arena */
   }
 
+  if ( AH->arena_base != (void *)AH ) {
+    void *arena_base = AH->arena_base;
+    /* Arena mapped in the wrong place */
+    lpsm_shutdown();		/* Nothing written... */
+    if ( !(AH = lpsm_arena_init(main_file, log_file, &arena_len, arena_base)) )
+      return NULL;		/* Failed to initialize arena */
+    if ( AH->arena_base != (void *)AH )
+      return NULL;		/* Something went weird... */
+  }
+
   return AH->root_data_ptrs;
 }