wait: fix support for wait -1

Only on unix systems. Does waitpid(-1, ...) to wait for any child
process to exit.

Signed-off-by: Steve Bennett <steveb@workware.net.au>

2 files changed, 17 insertions, 6 deletions

diff --git a/jim-exec.c b/jim-exec.c
index 74a4d18..be18fbb 100644
--- a/jim-exec.c
+++ b/jim-exec.c
@@ -614,6 +614,12 @@ static int Jim_WaitCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     if (phandle == JIM_BAD_PHANDLE) {
         pid = -1;
     }
+    else if (pid < 0) {
+        /* This catches the case where pid=-1. It is only supported on unix where
+         * the returned phandle is a pid, so can simply assign here
+         */
+        pid = phandle;
+    }
 
     errCodeObj = JimMakeErrorCode(interp, pid, status, NULL);
 
diff --git a/jimiocompat.c b/jimiocompat.c
index 665a65a..8e7f3f2 100644
--- a/jimiocompat.c
+++ b/jimiocompat.c
@@ -102,15 +102,20 @@ long JimProcessPid(phandle_t pid)
  * Returns the phandle of the process identified by 'pid' or JIM_BAD_PHANDLE on error.
  * Note that on success, the handle will no longer be valid.
  * It can only be used as a token (e.g. to look up the wait table)
+ *
+ * Note that Windows doesn't support waitpid(-1, ...) to wait for any child process
+ * so just always return JIM_BAD_PHANDLE in that case.
  */
 phandle_t JimWaitPid(long pid, int *status, int nohang)
 {
-    HANDLE h = OpenProcess(PROCESS_QUERY_INFORMATION | SYNCHRONIZE, FALSE, pid);
-    if (h) {
-        long pid = waitpid(h, status, nohang);
-        CloseHandle(h);
-        if (pid > 0) {
-            return h;
+    if (pid > 0) {
+        HANDLE h = OpenProcess(PROCESS_QUERY_INFORMATION | SYNCHRONIZE, FALSE, pid);
+        if (h) {
+            long pid = waitpid(h, status, nohang);
+            CloseHandle(h);
+            if (pid > 0) {
+                return h;
+            }
         }
     }
     return JIM_BAD_PHANDLE;