also join processes terminated by signal

[blank.git] / src / app / proc.cpp

diff --git a/src/app/proc.cpp b/src/app/proc.cpp
index f30c0cb2dcab508be7ee480fb63955f8fef721ff..add16d1787a4779068b6ce36b06be9c9d1d9e194 100644 (file)
--- a/src/app/proc.cpp
+++ b/src/app/proc.cpp
@@ -1,5 +1,7 @@
 #include "Process.hpp"
 
+#include "error.hpp"
+
 #ifdef _WIN32
 #  include <tchar.h>
 #  include <windows.h>
@@ -166,18 +168,18 @@ Process::Impl::Impl(
        argv[args.size()] = nullptr;
 
        if (pipe(fd_in) != 0) {
-               throw runtime_error("failed to open pipe for child process' stdin");
+               throw SysError("failed to open pipe for child process' stdin");
        }
        if (pipe(fd_out) != 0) {
-               throw runtime_error("failed to open pipe for child process' stdout");
+               throw SysError("failed to open pipe for child process' stdout");
        }
        if (pipe(fd_err) != 0) {
-               throw runtime_error("failed to open pipe for child process' stderr");
+               throw SysError("failed to open pipe for child process' stderr");
        }
 
        pid = fork();
        if (pid == -1) {
-               throw runtime_error("fork");
+               throw SysError("fork");
        } else if (pid == 0) {
 
                if (dup2(fd_in[0], STDIN_FILENO) == -1) {
@@ -228,7 +230,7 @@ size_t Process::Impl::WriteIn(const void *buffer, size_t max_len) {
                if (errno == EAGAIN) {
                        return 0;
                } else {
-                       throw runtime_error("failed to write to child process' input stream");
+                       throw SysError("failed to write to child process' input stream");
                }
        }
        return written;
@@ -248,7 +250,7 @@ size_t Process::Impl::ReadOut(void *buffer, size_t max_len) {
                if (errno == EAGAIN) {
                        return 0;
                } else {
-                       throw runtime_error("failed to read from child process' output stream");
+                       throw SysError("failed to read from child process' output stream");
                }
        }
        return ret;
@@ -268,7 +270,7 @@ size_t Process::Impl::ReadErr(void *buffer, size_t max_len) {
                if (errno == EAGAIN) {
                        return 0;
                } else {
-                       throw runtime_error("failed to read from child process' error stream");
+                       throw SysError("failed to read from child process' error stream");
                }
        }
        return ret;
@@ -281,7 +283,7 @@ void Process::Impl::Terminate() {
 #else
        if (kill(pid, SIGTERM) == -1) {
 #endif
-               throw runtime_error("failed to terminate child process");
+               throw SysError("failed to terminate child process");
        }
 }
 
@@ -307,13 +309,22 @@ int Process::Impl::Join() {
                int status;
                int result = waitpid(pid, &status, 0);
                if (result == -1) {
-                       throw runtime_error("error waiting on child process");
+                       throw SysError("error waiting on child process");
+               }
+               if (result != pid) {
+                       // should in theory only happen with WNOHANG set
+                       continue;
                }
-               if (result == pid && WIFEXITED(status)) {
+               if (WIFEXITED(status)) {
+                       // autonomous termination
                        return WEXITSTATUS(status);
                }
-               // otherwise, child probably signalled, which we don't care
-               // about (please don't tell youth welfare), so try again
+               if (WIFSIGNALED(status)) {
+                       // signalled termination
+                       return WTERMSIG(status);
+               }
+               // otherwise, child probably signalled stop/continue, which we
+               // don't care about (please don't tell youth welfare), so try again
        }
 #endif
 }