From 1b484566b3efd349b9e8baaa59a92d64a86f627d Mon Sep 17 00:00:00 2001
From: Marko Lindqvist <cazfi74@gmail.com>
Date: Sat, 11 Mar 2023 07:42:21 +0200
Subject: [PATCH 8/8] sdl2: Fix help NULL dereference for improvements with
 just negated reqs

See osdn #47559

Signed-off-by: Marko Lindqvist <cazfi74@gmail.com>
---
 client/gui-sdl2/helpdlg.c | 56 +++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 26 deletions(-)

diff --git a/client/gui-sdl2/helpdlg.c b/client/gui-sdl2/helpdlg.c
index ac0a07b558..d37d947bfd 100644
--- a/client/gui-sdl2/helpdlg.c
+++ b/client/gui-sdl2/helpdlg.c
@@ -238,11 +238,11 @@ void popup_impr_info(Impr_type_id impr)
     current_help_dlg = HELP_IMPROVEMENT;
     created = TRUE;
 
-    /* create dialog */
+    /* Create dialog */
     pHelpDlg = fc_calloc(1, sizeof(struct ADVANCED_DLG));
     pStore = fc_calloc(1, sizeof(struct UNITS_BUTTONS));
 
-    /* create window */
+    /* Create window */
     title = create_utf8_from_char(_("Help : Improvements"), adj_font(12));
     title->style |= TTF_STYLE_BOLD;
 
@@ -257,7 +257,7 @@ void popup_impr_info(Impr_type_id impr)
     area = pWindow->area;
     /* ------------------ */
 
-    /* close button */
+    /* Close button */
     pCloseButton = create_themeicon(current_theme->Small_CANCEL_Icon, pWindow->dst,
                                     WF_WIDGET_HAS_INFO_LABEL
                                     | WF_RESTORE_BACKGROUND);
@@ -337,7 +337,7 @@ void popup_impr_info(Impr_type_id impr)
 #if 0
    pListToggleButton->action = toggle_full_tree_mode_in_help_dlg_callback;
    if (pStore->show_tree) {
-      set_wstate(pListToggleButton, FC_WS_NORMAL);
+     set_wstate(pListToggleButton, FC_WS_NORMAL);
    }
 #endif
 
@@ -403,33 +403,36 @@ void popup_impr_info(Impr_type_id impr)
   DownAdd(pRequirementLabel, pDock);
   pDock = pRequirementLabel;
 
-  if (requirement_vector_size(&pImpr_type->reqs) == 0) {
+  /* FIXME: this should show ranges, negated reqs, and all the
+   * MAX_NUM_REQS reqs.
+   * Currently it's limited to 1 req. Remember MAX_NUM_REQS is a compile-time
+   * definition. */
+  requirement_vector_iterate(&pImpr_type->reqs, preq) {
+    if (!preq->present) {
+      continue;
+    }
+    pRequirementLabel2 = create_iconlabel_from_chars(NULL, pWindow->dst,
+                             universal_name_translation(&preq->source, buffer,
+                                                        sizeof(buffer)),
+                                                     adj_font(12), WF_RESTORE_BACKGROUND);
+    if (preq->source.kind != VUT_ADVANCE) {
+      break; /* FIXME */
+    }
+    pRequirementLabel2->ID = MAX_ID - advance_number(preq->source.value.advance);
+    pRequirementLabel2->string_utf8->fgcol
+      = *get_tech_color(advance_number(preq->source.value.advance));
+    pRequirementLabel2->action = change_tech_callback;
+    set_wstate(pRequirementLabel2, FC_WS_NORMAL);
+    break;
+  } requirement_vector_iterate_end;
+
+  if (pRequirementLabel2 == NULL) {
     pRequirementLabel2 = create_iconlabel_from_chars(NULL, pWindow->dst,
                                                      Q_("?req:None"),
                                                      adj_font(12), 0);
     pRequirementLabel2->ID = ID_LABEL;
-  } else {
-    /* FIXME: this should show ranges, negated reqs, and all the
-     * MAX_NUM_REQS reqs.
-     * Currently it's limited to 1 req. Remember MAX_NUM_REQS is a compile-time
-     * definition. */
-    requirement_vector_iterate(&pImpr_type->reqs, preq) {
-      if (!preq->present) {
-        continue;
-      }
-      pRequirementLabel2 = create_iconlabel_from_chars(NULL, pWindow->dst,
-                             universal_name_translation(&preq->source, buffer, sizeof(buffer)),
-                             adj_font(12), WF_RESTORE_BACKGROUND);
-      if (preq->source.kind != VUT_ADVANCE) {
-        break; /* FIXME */
-      }
-      pRequirementLabel2->ID = MAX_ID - advance_number(preq->source.value.advance);
-      pRequirementLabel2->string_utf8->fgcol = *get_tech_color(advance_number(preq->source.value.advance));
-      pRequirementLabel2->action = change_tech_callback;
-      set_wstate(pRequirementLabel2, FC_WS_NORMAL);
-      break;
-    } requirement_vector_iterate_end;
   }
+
   DownAdd(pRequirementLabel2, pDock);
   pDock = pRequirementLabel2;
   pStore->pRequirementButton = pRequirementLabel2;
@@ -448,6 +451,7 @@ void popup_impr_info(Impr_type_id impr)
       break;
     }
   } requirement_vector_iterate_end;
+
   if (obsTech == NULL) {
     pObsoleteByLabel2 = create_iconlabel_from_chars(NULL, pWindow->dst,
                                                     _("Never"), adj_font(12), 0);
-- 
2.39.2