X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;f=lib%2Fmmap.c;h=aa63622259d50034fce4b774dc600c92dcf1828b;hb=86919305a08aa88b3a60c3216752291ba7f0b496;hp=e461e1ee2838d48f0aded5e1b59765cf1a567a22;hpb=4bb1ae1d27874e3c1bf2817b740da096ac322f15;p=libucw.git

diff --git a/lib/mmap.c b/lib/mmap.c
index e461e1ee..aa636222 100644
--- a/lib/mmap.c
+++ b/lib/mmap.c
@@ -1,7 +1,10 @@
 /*
- *	Sherlock Library -- Mapping of Files
+ *	UCW Library -- Mapping of Files
  *
- *	(c) 1999 Martin Mares <mj@ucw.cz>
+ *	(c) 1999--2002 Martin Mares <mj@ucw.cz>
+ *
+ *	This software may be freely distributed and used according to the terms
+ *	of the GNU Lesser General Public License.
  */
 
 #include "lib/lib.h"
@@ -12,11 +15,6 @@
 #include <sys/stat.h>
 #include <sys/mman.h>
 
-#ifndef MAP_FAILED
-#warning System includes do not define MAP_FAILED.
-#define MAP_FAILED ((void *)-1L)
-#endif
-
 void *
 mmap_file(byte *name, unsigned *len, int writeable)
 {
@@ -25,17 +23,19 @@ mmap_file(byte *name, unsigned *len, int writeable)
   void *x;
 
   if (fd < 0)
-    return NULL;
+    die("open(%s): %m", name);
   if (fstat(fd, &st) < 0)
-    x = NULL;
-  else
+    die("fstat(%s): %m", name);
+  if (len)
+    *len = st.st_size;
+  if (st.st_size)
     {
-      if (len)
-	*len = st.st_size;
       x = mmap(NULL, st.st_size, writeable ? (PROT_READ | PROT_WRITE) : PROT_READ, MAP_SHARED, fd, 0);
       if (x == MAP_FAILED)
-	x = NULL;
+	die("mmap(%s): %m", name);
     }
+  else	/* For empty file, we can return any non-zero address */
+    x = "";
   close(fd);
   return x;
 }