From: Karl Waclawek <kwaclaw@users.sourceforge.net>
Date: Wed, 28 Jun 2006 02:55:51 +0000 (+0000)
Subject: Fix for bug #1513566: filemap() in readfilemap.c doesn't handle zero length
X-Git-Tag: R_2_0_1~55
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f18b068f383c80752d9ff7a371ea81b5a4febb66;p=libexpat

Fix for bug #1513566: filemap() in readfilemap.c doesn't handle zero length
files, and the same issue applies to filemap() in unixfilemap.c
---

diff --git a/expat/xmlwf/readfilemap.c b/expat/xmlwf/readfilemap.c
index 42b5e038..0a91f08b 100755
--- a/expat/xmlwf/readfilemap.c
+++ b/expat/xmlwf/readfilemap.c
@@ -57,9 +57,17 @@ filemap(const char *name,
     return 0;
   }
   nbytes = sb.st_size;
+  /* malloc will return NULL with nbytes == 0, handle files with size 0 */
+  if (nbytes == 0) {
+    static const char c = '\0';
+    processor(&c, 0, name, arg);
+    close(fd);
+    return 1;
+  }
   p = malloc(nbytes);
   if (!p) {
     fprintf(stderr, "%s: out of memory\n", name);
+    close(fd);
     return 0;
   }
   n = read(fd, p, nbytes);
diff --git a/expat/xmlwf/unixfilemap.c b/expat/xmlwf/unixfilemap.c
index 22048c82..93adce32 100755
--- a/expat/xmlwf/unixfilemap.c
+++ b/expat/xmlwf/unixfilemap.c
@@ -44,6 +44,13 @@ filemap(const char *name,
   }
 
   nbytes = sb.st_size;
+  /* mmap fails for zero length files */
+  if (nbytes == 0) {
+    static const char c = '\0';
+    processor(&c, 0, name, arg);
+    close(fd);
+    return 1;
+  }
   p = (void *)mmap((caddr_t)0, (size_t)nbytes, PROT_READ,
                    MAP_FILE|MAP_PRIVATE, fd, (off_t)0);
   if (p == (void *)-1) {