Factor out snprintf'ing a maybe-modDir'd file name into macro G_ModDirSnprintf().

... and use it in three places. In two of these uses,
1) CON {read,write}arrayfromfile and
2) G_SavePlayer,
display an error message if the file name such generated is too long.

In the CON commands of 1), also error out if the file couldn't be opened.

git-svn-id: https://svn.eduke32.com/eduke32@2997 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/source/demo.c

@@ -173,22 +173,17 @@ void G_OpenDemoWrite(void)
 
         do
         {
-            int32_t nch;
-
             if (demonum == 10000)
                 return;
 
-            if (g_modDir[0] != '/')
-                nch=Bsnprintf(demofn, sizeof(demofn), "%s/edemo%d.edm", g_modDir, demonum++);
-            else nch=Bsnprintf(demofn, sizeof(demofn), "edemo%d.edm", demonum++);
-
-            if ((unsigned)nch >= sizeof(demofn)-1)
+            if (G_ModDirSnprintf(demofn, sizeof(demofn), "edemo%d.edm", demonum))
             {
-                // TODO: factor out this out and use everywhere else.
                 initprintf("Couldn't start demo writing: INTERNAL ERROR: file name too long\n");
                 goto error_wopen_demo;
             }
 
+            demonum++;
+
             g_demo_filePtr = Bfopen(demofn, "rb");
             if (g_demo_filePtr == NULL)
                 break;

polymer/eduke32/source/game.h

@@ -372,4 +372,13 @@ enum {
     ST_31_TWO_WAY_TRAIN = 31,
 };
 
+# define G_ModDirSnprintf(buf, size, basename, ...) \
+( \
+    ( \
+        (g_modDir[0] != '/') ? \
+            Bsnprintf(buf, size, "%s/" basename, g_modDir, ## __VA_ARGS__) : \
+            Bsnprintf(buf, size, basename, ## __VA_ARGS__) \
+    ) >= ((int32_t)size)-1 \
+)
+
 #endif

polymer/eduke32/source/gameexec.c

@@ -4224,11 +4224,18 @@ nullquote:
                         FILE *fil;
                         char temp[BMAX_PATH];
 
-                        if (g_modDir[0] != '/')
-                            Bsprintf(temp,"%s/%s",g_modDir,ScriptQuotes[q]);
-                        else Bsprintf(temp,"%s",ScriptQuotes[q]);
+                        if (G_ModDirSnprintf(temp, sizeof(temp), "%s", ScriptQuotes[q]))
+                        {
+                            OSD_Printf(CON_ERROR "file name too long\n",g_errorLineNum,keyw[g_tw]);
+                            continue;
+                        }
 
-                        if ((fil = fopen(temp,"wb")) == 0) continue;
+                        fil = fopen(temp,"wb");
+                        if (fil == NULL)
+                        {
+                            OSD_Printf(CON_ERROR "couldn't open file",g_errorLineNum,keyw[g_tw]);
+                            continue;
+                        }
 
                         fwrite(aGameArrays[j].plValues,1,sizeof(int) * aGameArrays[j].size,fil);
                         fclose(fil);

polymer/eduke32/source/savegame.c

@@ -319,12 +319,11 @@ int32_t G_SavePlayer(int32_t spot)
     {
         char temp[BMAX_PATH];
 
-        // TODO: factor this out someday...
-        if (g_modDir[0] != '/')
-            Bsnprintf(temp, sizeof(temp), "%s/%s", g_modDir, fn);
-        else
-            Bsnprintf(temp, sizeof(temp), "%s", fn);
-        temp[sizeof(temp)-1] = 0;
+        if (G_ModDirSnprintf(temp, sizeof(temp), "%s", fn))
+        {
+            OSD_Printf("G_SavePlayer: file name \"%s\" too long\n", fn);
+            return -1;
+        }
 
         errno = 0;
         fil = fopen(temp, "wb");