Merge pull request #21207 from vespa-engine/havardpe/better-error-messages

better error messages

2 files changed, 29 insertions, 4 deletions

diff --git a/vespalib/src/vespa/vespalib/util/child_process.cpp b/vespalib/src/vespa/vespalib/util/child_process.cpp
index 7193a445f9a..694bed60f1b 100644
--- a/vespalib/src/vespa/vespalib/util/child_process.cpp
+++ b/vespalib/src/vespa/vespalib/util/child_process.cpp
@@ -67,7 +67,9 @@ ChildProcess::Reader::OnReceiveData(const void *data, size_t length)
         return;
     }
     if (buf == nullptr) { // EOF
-        _gotEOF = true;
+        if (--_num_streams == 0) {
+            _gotEOF = true;
+        }
     } else {
         _queue.push(std::string(buf, length));
     }
@@ -107,11 +109,12 @@ ChildProcess::Reader::updateEOF()
 }
 
 
-ChildProcess::Reader::Reader()
+ChildProcess::Reader::Reader(int num_streams)
     : _lock(),
       _cond(),
       _queue(),
       _data(),
+      _num_streams(num_streams),
       _gotEOF(false),
       _waitCnt(0),
       _readEOF(false)
@@ -203,7 +206,7 @@ ChildProcess::checkProc()
 
 
 ChildProcess::ChildProcess(const char *cmd)
-    : _reader(),
+    : _reader(1),
       _proc(cmd, true, &_reader),
       _running(false),
       _failed(false),
@@ -213,6 +216,17 @@ ChildProcess::ChildProcess(const char *cmd)
     _failed  = !_running;
 }
 
+ChildProcess::ChildProcess(const char *cmd, capture_stderr_tag)
+    : _reader(2),
+      _proc(cmd, true, &_reader, &_reader),
+      _running(false),
+      _failed(false),
+      _exitCode(-918273645)
+{
+    _running = _proc.CreateWithShell();
+    _failed  = !_running;
+}
+
 
 ChildProcess::~ChildProcess() = default;
 
diff --git a/vespalib/src/vespa/vespalib/util/child_process.h b/vespalib/src/vespa/vespalib/util/child_process.h
index 646a2c7c6c9..877c56a8cb1 100644
--- a/vespalib/src/vespa/vespalib/util/child_process.h
+++ b/vespalib/src/vespa/vespalib/util/child_process.h
@@ -28,6 +28,7 @@ private:
         std::condition_variable _cond;
         std::queue<std::string> _queue;
         std::string             _data;
+        int                     _num_streams;
         bool                    _gotEOF;
         int                     _waitCnt;
         bool                    _readEOF;
@@ -38,7 +39,7 @@ private:
         void updateEOF();
 
     public:
-        Reader();
+        Reader(int num_streams);
         ~Reader() override;
 
         uint32_t read(char *buf, uint32_t len, int msTimeout);
@@ -57,6 +58,7 @@ private:
 public:
     ChildProcess(const ChildProcess &) = delete;
     ChildProcess &operator=(const ChildProcess &) = delete;
+    struct capture_stderr_tag{};
     
     /**
      * @brief Run a child process
@@ -66,6 +68,15 @@ public:
      **/
     explicit ChildProcess(const char *cmd);
 
+    /**
+     * @brief Run a child process
+     *
+     * Starts a process running the given command. stderr is
+     * redirected into stdout.
+     * @param cmd A shell command line to run
+     **/
+    explicit ChildProcess(const char *cmd, capture_stderr_tag);
+
     /** @brief destructor doing cleanup if needed */
     ~ChildProcess();