Ignore SIGPIPE in writer thread (*nix only). Reason:

Writing to a pipe with no reader raises a signal and returns
error.  The Child class handles the error returned.  Not ignoring
the signal would result in aborting the process.


git-svn-id: https://svn.microneil.com/svn/CodeDweller/branches/adeniz_1@115 d34b734f-a00e-4b39-a726-e4eeb87269ab

child.cpp

@@ -848,6 +848,7 @@ namespace CodeDweller {
 
     childStarted = false;
     childExited = false;
+    childExitedInferred = false;
     exitCodeObtainedFlag = false;
     exitCode = 0;
 
@@ -1021,7 +1022,7 @@ namespace CodeDweller {
   }
 
   bool Child::isRunning() const {
-    return childStarted && !childExited;
+    return childStarted && !childExited && !childExitedInferred;
   }
 
   bool Child::errorOccurred(std::string &errorDescription) const {
@@ -1137,7 +1138,7 @@ namespace CodeDweller {
 			   &startInfo,    // STARTUPINFO pointer 
 			   &processInfo); // receives PROCESS_INFORMATION 
 
-    // If an error occurs, exit the application. 
+    // If an error occurs, throw.
     if (!status ) {
       throw std::runtime_error("Error from CreateProcess with "
 			       "command line \"" + cmdline + "\":  " +
@@ -1484,6 +1485,7 @@ namespace CodeDweller {
       nBytesRead = ::read(inputFileDescriptor,
                           bufferPtr,
                           bufferCapacity);
+
       if (-1 == nBytesRead) {
 
         if (stopReaderFlag) {
@@ -1497,6 +1499,8 @@ namespace CodeDweller {
       } else if (0 == nBytesRead) {
 
         // EOF; child exited.
+        childExitedInferred = true;
+        stopWriterFlag = true;
         break;
 
       }
@@ -1539,6 +1543,14 @@ namespace CodeDweller {
 
   void Child::writeToChild() {
 
+#ifndef _WIN32
+
+    // Writing to a broken pipe raises SIGPIPE.  Ignore that signal;
+    // the error is handled by the return value of ::write.
+    signal(SIGPIPE, SIG_IGN);
+
+#endif
+
     std::vector<char> localWriteBuffer(bufferCapacity);
     size_t nLocalWriteBytes;
 

child.hpp

@@ -910,7 +910,6 @@ namespace CodeDweller {
     */
     template<typename T>
     size_t writeAndShrink(T &data) {
-
       if (!isRunning()) {
         throw std::logic_error("No child process is running.");
       }
@@ -934,6 +933,7 @@ namespace CodeDweller {
       std::copy(data.begin(),
                 data.begin() + nBytesToCopy,
                 &(writeBuffer[nWriteBytes]));
+
       nWriteBytes += nBytesToCopy;
 
       data.erase(data.begin(), data.begin() + nBytesToCopy);
@@ -1307,9 +1307,13 @@ namespace CodeDweller {
     /// True if the child process was successfully started.
     bool childStarted;
 
-    /// True if the child process has exited.
+    /// True if a system call indicates that the child process has
+    /// exited.
     bool childExited;
 
+    /// True if the child exited for any other reason.
+    bool childExitedInferred;
+
     /// Child executable path and command-line parameters.
     std::vector<std::string> cmdArgs;