ceph: don't write output on error

Accumulate all output, and write it at the end.  This way we can avoid
writing it if any of the commands fail.

Fixes: #1954
Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/src/tools/ceph.cc b/src/tools/ceph.cc
index 1bf3c00d2d8f65841ae563230653947b42c34dc8..919354657e8de1591eb89c5cb6a2789535884318 100644 (file)
--- a/src/tools/ceph.cc
+++ b/src/tools/ceph.cc
@@ -210,22 +210,6 @@ int main(int argc, const char **argv)
     }
   }
 
-  // output
-  int out_fd;
-  bool close_out_fd = false;
-  if (out_file.empty() || out_file == "-") {
-    out_fd = STDOUT_FILENO;
-  } else {
-    out_fd = TEMP_FAILURE_RETRY(::open(out_file.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0644));
-    if (out_fd < 0) {
-      int ret = errno;
-      derr << " failed to create file '" << out_file << "': "
-          << cpp_strerror(ret) << dendl;
-      return 1;
-    }
-    close_out_fd = true;
-  }
-
   CephToolCtx *ctx = ceph_tool_common_init(mode, concise);
   if (!ctx) {
     derr << "ceph_tool_common_init failed." << dendl;
@@ -234,6 +218,7 @@ int main(int argc, const char **argv)
   signal(SIGINT, SIG_DFL);
   signal(SIGTERM, SIG_DFL);
 
+  bufferlist outbl;
   int ret = 0;
   switch (mode) {
     case CEPH_TOOL_MODE_ONE_SHOT_OBSERVER: // fall through
@@ -261,18 +246,10 @@ int main(int argc, const char **argv)
          }
 
          bufferlist obl;
-         if (do_command(ctx, cmd, indata, obl))
+         if (do_command(ctx, cmd, indata, obl) < 0)
            ret = 1;
-         if (obl.length()) {
-           int err = obl.write_fd(out_fd);
-           if (err) {
-             derr << " failed to write " << obl.length() << " bytes to " << out_file << ": "
-                  << cpp_strerror(err) << dendl;
-             goto out;
-           }
-           if (!concise && !out_file.empty())
-             cerr << " wrote " << obl.length() << " byte payload to " << out_file << std::endl;
-         }
+         else
+           outbl.claim(obl);
        }
       }
       if (ceph_tool_messenger_shutdown())
@@ -286,10 +263,31 @@ int main(int argc, const char **argv)
       break;
     }
   }
+ 
+  if (ret == 0 && outbl.length()) {
+    // output
+    int err;
+    if (out_file.empty() || out_file == "-") {
+      err = outbl.write_fd(STDOUT_FILENO);
+    } else {
+      int out_fd = TEMP_FAILURE_RETRY(::open(out_file.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0644));
+      if (out_fd < 0) {
+       int ret = errno;
+       derr << " failed to create file '" << out_file << "': "
+            << cpp_strerror(ret) << dendl;
+       return 1;
+      }
+      err = outbl.write_fd(out_fd);
+      ::close(out_fd);
+    }
+    if (err) {
+      derr << " failed to write " << outbl.length() << " bytes to " << out_file << ": "
+          << cpp_strerror(err) << dendl;
+      ret = 1;
+    } else if (!concise && !out_file.empty())
+      cerr << " wrote " << outbl.length() << " byte payload to " << out_file << std::endl;
+  }
 
- out:
-  if (close_out_fd)
-    ::close(out_fd);
   if (ceph_tool_common_shutdown(ctx))
     ret = 1;
   return ret;