Call OpenProcess() from within __archive_create_child()

Move the Windows specific to the Windows version of the helper, making
the existing code shorter and simpler.

This means that the child "handle" type will vary across the two
platforms - something that we've already been doing with waitpid.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>

Author: evelikov

libarchive/archive_read_support_filter_program.c

@@ -400,7 +400,6 @@ __archive_read_program(struct archive_read_filter *self, const char *cmd)
 	static const size_t out_buf_len = 65536;
 	char *out_buf;
 	const char *prefix = "Program: ";
-	pid_t child;
 	int ret;
 	size_t l;
 
@@ -428,7 +427,7 @@ __archive_read_program(struct archive_read_filter *self, const char *cmd)
 	state->out_buf_len = out_buf_len;
 
 	ret = __archive_create_child(cmd, &state->child_stdin,
-	    &state->child_stdout, &child);
+	    &state->child_stdout, &state->child);
 	if (ret != ARCHIVE_OK) {
 		free(state->out_buf);
 		archive_string_free(&state->description);
@@ -438,21 +437,6 @@ __archive_read_program(struct archive_read_filter *self, const char *cmd)
 		    cmd);
 		return (ARCHIVE_FATAL);
 	}
-#if defined(_WIN32) && !defined(__CYGWIN__)
-	state->child = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, child);
-	if (state->child == NULL) {
-		child_stop(self, state);
-		free(state->out_buf);
-		archive_string_free(&state->description);
-		free(state);
-		archive_set_error(&self->archive->archive, EINVAL,
-		    "Can't initialize filter; unable to run program \"%s\"",
-		    cmd);
-		return (ARCHIVE_FATAL);
-	}
-#else
-	state->child = child;
-#endif
 
 	self->data = state;
 	self->read = program_filter_read;

libarchive/archive_write_add_filter_program.c

@@ -211,7 +211,6 @@ int
 __archive_write_program_open(struct archive_write_filter *f,
     struct archive_write_program_data *data, const char *cmd)
 {
-	pid_t child;
 	int ret;
 
 	if (data->child_buf == NULL) {
@@ -227,26 +226,12 @@ __archive_write_program_open(struct archive_write_filter *f,
 	}
 
 	ret = __archive_create_child(cmd, &data->child_stdin,
-		    &data->child_stdout, &child);
+		    &data->child_stdout, &data->child);
 	if (ret != ARCHIVE_OK) {
 		archive_set_error(f->archive, EINVAL,
 		    "Can't launch external program: %s", cmd);
 		return (ARCHIVE_FATAL);
 	}
-#if defined(_WIN32) && !defined(__CYGWIN__)
-	data->child = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, child);
-	if (data->child == NULL) {
-		close(data->child_stdin);
-		data->child_stdin = -1;
-		close(data->child_stdout);
-		data->child_stdout = -1;
-		archive_set_error(f->archive, EINVAL,
-		    "Can't launch external program: %s", cmd);
-		return (ARCHIVE_FATAL);
-	}
-#else
-	data->child = child;
-#endif
 	return (ARCHIVE_OK);
 }
 

libarchive/filter_fork.h

@@ -34,7 +34,11 @@
 
 int
 __archive_create_child(const char *cmd, int *child_stdin, int *child_stdout,
+#if defined(_WIN32) && !defined(__CYGWIN__)
+	HANDLE *out_child);
+#else
 	pid_t *out_child);
+#endif
 
 void
 __archive_check_child(int in, int out);

libarchive/filter_fork_windows.c

@@ -33,7 +33,7 @@
 
 int
 __archive_create_child(const char *cmd, int *child_stdin, int *child_stdout,
-		pid_t *out_child)
+		HANDLE *out_child)
 {
 	HANDLE childStdout[2], childStdin[2],childStderr;
 	SECURITY_ATTRIBUTES secAtts;
@@ -45,6 +45,7 @@ __archive_create_child(const char *cmd, int *child_stdin, int *child_stdout,
 	char *arg0, *ext;
 	int i, l;
 	DWORD fl, fl_old;
+	HANDLE child;
 
 	childStdout[0] = childStdout[1] = INVALID_HANDLE_VALUE;
 	childStdin[0] = childStdin[1] = INVALID_HANDLE_VALUE;
@@ -155,13 +156,19 @@ __archive_create_child(const char *cmd, int *child_stdin, int *child_stdout,
 	*child_stdout = _open_osfhandle((intptr_t)childStdout[0], _O_RDONLY);
 	*child_stdin = _open_osfhandle((intptr_t)childStdin[1], _O_WRONLY);
 
+	child = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE,
+		childInfo.dwProcessId);
+	if (child == NULL) // INVALID_HANDLE_VALUE ?
+		goto fail;
+
+	*out_child = child;
+
 	CloseHandle(childStdout[1]);
 	CloseHandle(childStdin[0]);
 
 	archive_string_free(&cmdline);
 	archive_string_free(&fullpath);
 	__archive_cmdline_free(acmd);
-	*out_child = childInfo.dwProcessId;
 	return ARCHIVE_OK;
 
 fail: