From b77b77130ad1732903236e327b6f2665c7ade200 Mon Sep 17 00:00:00 2001
From: Perry Werneck <perry.werneck@gmail.com>
Date: Wed, 20 Nov 2019 11:38:48 -0300
Subject: [PATCH] Adjustments in selection to help the diagnose of segfaults on print dialog.

---
 src/include/lib3270/selection.h | 16 ++++++++++++++--
 src/selection/get.c             | 34 +++++++++++++++++++++++++++++++++-
 2 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/src/include/lib3270/selection.h b/src/include/lib3270/selection.h
index 38ddc06..55fceae 100644
--- a/src/include/lib3270/selection.h
+++ b/src/include/lib3270/selection.h
@@ -190,7 +190,7 @@
 	LIB3270_EXPORT int lib3270_get_selection_rectangle(H3270 *hSession, unsigned int *row, unsigned int *col, unsigned int *width, unsigned int *height);
 
 	/**
-	 * @brief Get selection contents.
+	 * @brief Create a new selection block.
 	 *
 	 * @param hSession	Session handle.
 	 * @param cut		Non zero to clear selected contents.
@@ -199,7 +199,19 @@
 	 * @return NULL on error (sets errno), pointer to a rectangle containing the selected area (release it with lib3270_free).
 	 *
 	 */
-	LIB3270_EXPORT lib3270_selection * lib3270_get_selection(H3270 *hSession, int cut, int all);
+	LIB3270_EXPORT lib3270_selection * lib3270_selection_new(H3270 *hSession, int cut, int all);
+
+	LIB3270_EXPORT lib3270_selection * LIB3270_DEPRECATED(lib3270_get_selection(H3270 *hSession, int cut, int all));
+
+	/**
+	 * @brief Get the length of the selection block.
+	 *
+	 * @param selection	Selection block.
+	 *
+	 * @return The length of the selection block.
+	 *
+	 */
+	LIB3270_EXPORT size_t lib3270_selection_get_length(const lib3270_selection *selection);
 
 	/**
 	 * @brief Get bitmasked flag for the current selection.
diff --git a/src/selection/get.c b/src/selection/get.c
index b69b7c9..651e06f 100644
--- a/src/selection/get.c
+++ b/src/selection/get.c
@@ -31,6 +31,8 @@
  #include <lib3270.h>
  #include <lib3270/session.h>
  #include <lib3270/selection.h>
+ #include <lib3270/trace.h>
+ #include <lib3270/log.h>
  #include "3270ds.h"
 
  /*--[ Implement ]------------------------------------------------------------------------------------*/
@@ -144,8 +146,23 @@ LIB3270_EXPORT char * lib3270_cut_selected(H3270 *hSession)
 	return lib3270_get_selected_text(hSession,0,LIB3270_SELECTION_CUT);
 }
 
+static size_t get_selection_length(unsigned int width, unsigned int height)
+{
+	return sizeof(lib3270_selection) + (sizeof(lib3270_selection_element) * ((width*height)+1));
+}
+
+LIB3270_EXPORT size_t lib3270_selection_get_length(const lib3270_selection *selection)
+{
+	return get_selection_length(selection->bounds.width,selection->bounds.height);
+}
+
 LIB3270_EXPORT lib3270_selection * lib3270_get_selection(H3270 *hSession, int cut, int all)
 {
+	return lib3270_selection_new(hSession,cut,all);
+}
+
+LIB3270_EXPORT lib3270_selection * lib3270_selection_new(H3270 *hSession, int cut, int all)
+{
 	if(check_online_session(hSession))
 		return NULL;
 
@@ -164,7 +181,10 @@ LIB3270_EXPORT lib3270_selection * lib3270_get_selection(H3270 *hSession, int cu
 	}
 
 	// Get output buffer.
-	lib3270_selection * selection = lib3270_malloc(sizeof(lib3270_selection) + (sizeof(lib3270_selection_element) * (width*height)));
+	size_t length = get_selection_length(width, height);
+	lib3270_selection * selection = lib3270_malloc(length);
+
+	memset(selection,0,length);
 
 	selection->bounds.col		= col;
 	selection->bounds.row		= row;
@@ -172,6 +192,16 @@ LIB3270_EXPORT lib3270_selection * lib3270_get_selection(H3270 *hSession, int cu
 	selection->bounds.width		= width;
 	selection->cursor_address	= lib3270_get_cursor_address(hSession);
 
+	debug(
+		"width=%u height=%u length=%u (sz=%u szHeader=%u szElement=%u)",
+			selection->bounds.width,
+			selection->bounds.height,
+			((selection->bounds.width * selection->bounds.height) + 1),
+			(unsigned int) length,
+			(unsigned int) sizeof(lib3270_selection),
+			(unsigned int) sizeof(lib3270_selection_element)
+	);
+
 	unsigned int dstaddr = 0;
 
 	for(row=0;row < selection->bounds.height; row++)
@@ -206,5 +236,7 @@ LIB3270_EXPORT lib3270_selection * lib3270_get_selection(H3270 *hSession, int cu
 
 	}
 
+	debug("dstaddr=%u length=%u",(unsigned int) dstaddr, (unsigned int) length);
+
 	return selection;
 }
--
libgit2 0.21.2