X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/977f0ae037cfbf3681ef2240be5b5272224a1d0c..7b9d41b862392e119cc9657af14cd53603ab2eb5:/src/xbt/mmalloc/mmorecore.c

diff --git a/src/xbt/mmalloc/mmorecore.c b/src/xbt/mmalloc/mmorecore.c
index 9d78336d0b..a2f6cfedb9 100644
--- a/src/xbt/mmalloc/mmorecore.c
+++ b/src/xbt/mmalloc/mmorecore.c
@@ -3,8 +3,7 @@
 
    Contributed by Fred Fish at Cygnus Support.   fnf@cygnus.com */
 
-/* Copyright (c) 2010. The SimGrid Team.
- * All rights reserved.                                                     */
+/* Copyright (c) 2010-2012. The SimGrid Team. All rights reserved.          */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
@@ -21,7 +20,6 @@
 #include <sys/mman.h>
 
 #include "mmprivate.h"
-#include "xbt/ex.h"
 
 /* Cache the pagesize for the current host machine.  Note that if the host
    does not readily provide a getpagesize() function, we need to emulate it
@@ -31,38 +29,41 @@
 static size_t pagesize;
 
 #define PAGE_ALIGN(addr) (void*) (((long)(addr) + pagesize - 1) & \
-				    ~(pagesize - 1))
+                                  ~(pagesize - 1))
 
 /* Return MAP_PRIVATE if MDP represents /dev/zero.  Otherwise, return
    MAP_SHARED.  */
 #define MAP_PRIVATE_OR_SHARED(MDP) (( MDP -> flags & MMALLOC_ANONYMOUS) \
-                                    ? MAP_PRIVATE \
+                                    ? MAP_PRIVATE                       \
                                     : MAP_SHARED)
 
 /* Return MAP_ANONYMOUS if MDP uses anonymous mapping. Otherwise, return 0 */
 #define MAP_IS_ANONYMOUS(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
-                              ? MAP_ANONYMOUS \
-                              : 0)
+                               ? MAP_ANONYMOUS                      \
+                               : 0)
 
 /* Return -1 if MDP uses anonymous mapping. Otherwise, return MDP->FD */
 #define MAP_ANON_OR_FD(MDP) (((MDP) -> flags & MMALLOC_ANONYMOUS) \
-                              ? -1 \
-                  			      : (MDP) -> fd)
+                             ? -1                                 \
+                             : (MDP) -> fd)
 
 /*  Get core for the memory region specified by MDP, using SIZE as the
     amount to either add to or subtract from the existing region.  Works
-    like sbrk(), but using mmap(). */
+    like sbrk(), but using mmap().
 
-void *mmorecore(struct mdesc *mdp, int size)
+    It never returns NULL. Instead, it dies verbosely on errors. */
+
+void *mmorecore(struct mdesc *mdp, size_t size)
 {
   ssize_t test = 0;
-  void *result = NULL;
+  void *result; // please keep it uninitialized to track issues
   off_t foffset;                /* File offset at which new mapping will start */
   size_t mapbytes;              /* Number of bytes to map */
   void *moveto;                 /* Address where we wish to move "break value" to */
   void *mapto;                  /* Address we actually mapped to */
   char buf = 0;                 /* Single byte to write to extend mapped file */
 
+//  fprintf(stderr,"increase %p by %u\n",mdp,size);
   if (pagesize == 0)
     pagesize = getpagesize();
 
@@ -73,8 +74,8 @@ void *mmorecore(struct mdesc *mdp, int size)
   } else if (size < 0) {
     /* We are deallocating memory.  If the amount requested would cause
        us to try to deallocate back past the base of the mmap'd region
-       then do nothing, and return NULL.  Otherwise, deallocate the
-       memory and return the old break value. */
+       then die verbosely.  Otherwise, deallocate the memory and return
+       the old break value. */
     if (((char *) mdp->breakval) + size >= (char *) mdp->base) {
       result = (void *) mdp->breakval;
       mdp->breakval = (char *) mdp->breakval + size;
@@ -82,13 +83,16 @@ void *mmorecore(struct mdesc *mdp, int size)
       munmap(moveto,
              (size_t) (((char *) mdp->top) - ((char *) moveto)) - 1);
       mdp->top = moveto;
+    } else {
+      fprintf(stderr,"Internal error: mmap was asked to deallocate more memory than it previously allocated. Bailling out now!\n");
+      abort();
     }
   } else {
     /* We are allocating memory. Make sure we have an open file
        descriptor if not working with anonymous memory. */
     if (!(mdp->flags & MMALLOC_ANONYMOUS) && mdp->fd < 0) {
-      THROWF(system_error,0,"mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags",mdp->fd);
-      result = NULL;
+      fprintf(stderr,"Internal error: mmap file descriptor <0 (%d), without MMALLOC_ANONYMOUS being in the flags.\n",mdp->fd);
+      abort();
     } else if ((char *) mdp->breakval + size > (char *) mdp->top) {
       /* The request would move us past the end of the currently
          mapped memory, so map in enough more memory to satisfy
@@ -103,8 +107,10 @@ void *mmorecore(struct mdesc *mdp, int size)
         /* FIXME:  Test results of lseek() */
         lseek(mdp->fd, foffset + mapbytes - 1, SEEK_SET);
         test = write(mdp->fd, &buf, 1);
-        if (test == -1)
-          THROWF(system_error, 0, "write to mmap'ed fd failed! error: %s", strerror(errno));
+        if (test == -1) {
+          fprintf(stderr,"Internal error: write to mmap'ed fd failed! error: %s", strerror(errno));
+          abort();
+        }
       }
 
       /* Let's call mmap. Note that it is possible that mdp->top
@@ -113,17 +119,23 @@ void *mmorecore(struct mdesc *mdp, int size)
                    MAP_PRIVATE_OR_SHARED(mdp) | MAP_IS_ANONYMOUS(mdp) |
                    MAP_FIXED, MAP_ANON_OR_FD(mdp), foffset);
 
-      if (mapto != (void *) -1/* That's MAP_FAILED */) {
+      if (mapto == (void *) -1/* That's MAP_FAILED */) {
+        char buff[1024];
+        fprintf(stderr,"Internal error: mmap returned MAP_FAILED! error: %s\n",strerror(errno));
+        sprintf(buff,"cat /proc/%d/maps",getpid());
+        int status = system(buff);
+        if (status == -1 || !(WIFEXITED(status) && WEXITSTATUS(status) == 0))
+          fprintf(stderr, "Something went wrong when trying to %s\n", buff);
+        sleep(1);
+        abort();
+      }
 
-        if (mdp->top == 0)
-          mdp->base = mdp->breakval = mapto;
+      if (mdp->top == 0)
+        mdp->base = mdp->breakval = mapto;
 
-        mdp->top = PAGE_ALIGN((char *) mdp->breakval + size);
-        result = (void *) mdp->breakval;
-        mdp->breakval = (char *) mdp->breakval + size;
-      } else {
-	THROWF(system_error,0,"mmap returned MAP_FAILED! error: %s",strerror(errno));
-      }
+      mdp->top = PAGE_ALIGN((char *) mdp->breakval + size);
+      result = (void *) mdp->breakval;
+      mdp->breakval = (char *) mdp->breakval + size;
     } else {
       result = (void *) mdp->breakval;
       mdp->breakval = (char *) mdp->breakval + size;