fix for bug #367084: updater can fail to apply updates if files have the

"read only" attribute set.

r=bsmedberg

toolkit/mozapps/update/src/updater/updater.cpp

@@ -353,6 +353,33 @@ mstrtok(const char *delims, char **str)
   return ret;
 }
 
+static void ensure_write_permissions(const char *path)
+{
+#ifdef XP_WIN
+  (void)_chmod(path, _S_IREAD | _S_IWRITE);
+#else
+  struct stat fs;
+  if (!stat(path, &fs) && !(fs.st_mode & S_IWUSR)) {
+    (void)chmod(path, fs.st_mode | S_IWUSR);
+  }
+#endif
+}
+
+static int ensure_remove(const char *path)
+{
+  ensure_write_permissions(path);
+  int rv = remove(path);
+  if (rv)
+    LOG(("remove failed: %d,%d (%s)\n", rv, errno, path));
+  return rv;
+}
+
+static int ensure_open(const char *path, int flags, int options)
+{
+  ensure_write_permissions(path);
+  return open(path, flags, options);
+}
+
 // Ensure that the directory containing this file exists.
 static int ensure_parent_dir(const char *path)
 {
@@ -391,7 +418,7 @@ static int copy_file(const char *spath, const char *dpath)
     return READ_ERROR;
   }
 
-  AutoFD dfd = open(dpath, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, ss.st_mode);
+  AutoFD dfd = ensure_open(dpath, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, ss.st_mode);
   if (dfd < 0) {
     LOG(("copy_file: failed to open: %s,%d\n", dpath, errno));
     return WRITE_ERROR;
@@ -445,7 +472,7 @@ static int backup_restore(const char *path)
   if (rv)
     return rv;
 
-  rv = remove(backup);
+  rv = ensure_remove(backup);
   if (rv)
     return WRITE_ERROR;
 
@@ -458,7 +485,7 @@ static int backup_discard(const char *path)
   char backup[MAXPATHLEN];
   snprintf(backup, sizeof(backup), "%s" BACKUP_EXT, path);
 
-  int rv = remove(backup);
+  int rv = ensure_remove(backup);
   if (rv)
     return WRITE_ERROR;
 
@@ -591,11 +618,9 @@ RemoveFile::Execute()
     return rv;
   }
 
-  rv = remove(mFile);
-  if (rv) {
-    LOG(("remove failed: %d\n", rv));
+  rv = ensure_remove(mFile);
+  if (rv)
     return WRITE_ERROR;
-  }
 
   return OK;
 }
@@ -659,7 +684,7 @@ AddFile::Execute()
     if (rv)
       return rv;
 
-    rv = remove(mFile);
+    rv = ensure_remove(mFile);
     if (rv)
       return WRITE_ERROR;
   }
@@ -715,7 +740,7 @@ PatchFile::~PatchFile()
   // delete the temporary patch file
   char spath[MAXPATHLEN];
   snprintf(spath, MAXPATHLEN, "%s/%d.patch", gSourcePath, mPatchIndex);
-  remove(spath);
+  ensure_remove(spath);
 
   free(buf);
 }
@@ -793,7 +818,7 @@ PatchFile::Prepare()
   char spath[MAXPATHLEN];
   snprintf(spath, MAXPATHLEN, "%s/%d.patch", gSourcePath, mPatchIndex);
 
-  remove(spath);
+  ensure_remove(spath);
 
   int rv = gArchiveReader.ExtractFile(mPatchFile, spath);
   if (rv)
@@ -836,11 +861,11 @@ PatchFile::Execute()
   if (rv)
     return rv;
 
-  rv = remove(mFile);
+  rv = ensure_remove(mFile);
   if (rv)
     return WRITE_ERROR;
 
-  AutoFD ofd = open(mFile, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, ss.st_mode);
+  AutoFD ofd = ensure_open(mFile, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, ss.st_mode);
   if (ofd < 0)
     return WRITE_ERROR;
 
@@ -1011,7 +1036,7 @@ WriteStatusFile(int status)
   char filename[MAXPATHLEN];
   snprintf(filename, MAXPATHLEN, "%s/update.status", gSourcePath);
 
-  AutoFD fd = open(filename, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, 0644);
+  AutoFD fd = ensure_open(filename, O_WRONLY | O_TRUNC | O_CREAT | _O_BINARY, 0644);
   if (fd < 0)
     return;