Replace all snprintf() calls with M_snprintf().

The Windows API has an _snprintf function that is not the same as
Unix's snprintf(): if the string is truncated then no trailing NUL
character is appended. This makes the function unsafe. Define a
replacement/wrapper called M_snprintf that works the same but always
appends a trailing NUL, for safety on Windows and other OSes that
behave like this.

Do the same thing for vsnprintf(), and update HACKING to list
snprintf/vsnprintf as forbidden functions. This fixes #375;
thanks to Quasar for pointing out the different behavior of these
functions.

10 files changed, 65 insertions, 62 deletions

diff --git a/src/hexen/am_map.c b/src/hexen/am_map.c
index 21b6c45c..cbbb3586 100644
--- a/src/hexen/am_map.c
+++ b/src/hexen/am_map.c
@@ -29,6 +29,7 @@
 #include "i_video.h"
 #include "i_swap.h"
 #include "m_controls.h"
+#include "m_misc.h"
 #include "p_local.h"
 #include "am_map.h"
 #include "am_data.h"
@@ -1474,8 +1475,8 @@ void AM_DrawDeathmatchStats(void)
         else
         {
             MN_DrTextA(PlayerColorText[order[i]], 8, yPosition);
-            snprintf(textBuffer, sizeof(textBuffer),
-                     "%d", fragCount[order[i]]);
+            M_snprintf(textBuffer, sizeof(textBuffer),
+                       "%d", fragCount[order[i]]);
             MN_DrTextA(textBuffer, 80, yPosition);
             yPosition += 10;
         }
@@ -1509,19 +1510,19 @@ static void DrawWorldTimer(void)
     worldTimer -= minutes * 60;
     seconds = worldTimer;
 
-    snprintf(timeBuffer, sizeof(timeBuffer),
-             "%.2d : %.2d : %.2d", hours, minutes, seconds);
+    M_snprintf(timeBuffer, sizeof(timeBuffer),
+               "%.2d : %.2d : %.2d", hours, minutes, seconds);
     MN_DrTextA(timeBuffer, 240, 8);
 
     if (days)
     {
         if (days == 1)
         {
-            snprintf(dayBuffer, sizeof(dayBuffer), "%.2d DAY", days);
+            M_snprintf(dayBuffer, sizeof(dayBuffer), "%.2d DAY", days);
         }
         else
         {
-            snprintf(dayBuffer, sizeof(dayBuffer), "%.2d DAYS", days);
+            M_snprintf(dayBuffer, sizeof(dayBuffer), "%.2d DAYS", days);
         }
         MN_DrTextA(dayBuffer, 240, 20);
         if (days >= 5)
diff --git a/src/hexen/h2_main.c b/src/hexen/h2_main.c
index 607bc26b..a7c3dee3 100644
--- a/src/hexen/h2_main.c
+++ b/src/hexen/h2_main.c
@@ -172,7 +172,7 @@ void D_BindVariables(void)
     {
         char buf[12];
 
-        snprintf(buf, sizeof(buf), "chatmacro%i", i);
+        M_snprintf(buf, sizeof(buf), "chatmacro%i", i);
         M_BindVariable(buf, &chat_macros[i]);
     }
 }
@@ -190,7 +190,7 @@ static void D_SetDefaultSavePath(void)
     if (!strcmp(SavePath, ""))
     {
         SavePath = malloc(10);
-	snprintf(SavePath, 10, "hexndata%c", DIR_SEPARATOR);
+	M_snprintf(SavePath, 10, "hexndata%c", DIR_SEPARATOR);
     }
 }
 
@@ -632,7 +632,7 @@ void H2_GameLoop(void)
     if (M_CheckParm("-debugfile"))
     {
         char filename[20];
-        snprintf(filename, sizeof(filename), "debug%i.txt", consoleplayer);
+        M_snprintf(filename, sizeof(filename), "debug%i.txt", consoleplayer);
         debugfile = fopen(filename, "w");
     }
     I_SetWindowTitle("Hexen");
diff --git a/src/hexen/in_lude.c b/src/hexen/in_lude.c
index b1d0c4c9..fb1b1020 100644
--- a/src/hexen/in_lude.c
+++ b/src/hexen/in_lude.c
@@ -28,6 +28,7 @@
 #include "s_sound.h"
 #include "i_system.h"
 #include "i_video.h"
+#include "m_misc.h"
 #include "p_local.h"
 #include "v_video.h"
 
@@ -537,8 +538,8 @@ static void DrNumber(int val, int x, int y, int wrapThresh)
 
     if (!(val < -9 && wrapThresh < 1000))
     {
-        snprintf(buff, sizeof(buff), "%d",
-                 val >= wrapThresh ? val % wrapThresh : val);
+        M_snprintf(buff, sizeof(buff), "%d",
+                   val >= wrapThresh ? val % wrapThresh : val);
     }
     MN_DrTextA(buff, x - MN_TextAWidth(buff) / 2, y);
 }
@@ -555,8 +556,8 @@ static void DrNumberBold(int val, int x, int y, int wrapThresh)
 
     if (!(val < -9 && wrapThresh < 1000))
     {
-        snprintf(buff, sizeof(buff), "%d",
-                 val >= wrapThresh ? val % wrapThresh : val);
+        M_snprintf(buff, sizeof(buff), "%d",
+                   val >= wrapThresh ? val % wrapThresh : val);
     }
     MN_DrTextAYellow(buff, x - MN_TextAWidth(buff) / 2, y);
 }
diff --git a/src/hexen/mn_menu.c b/src/hexen/mn_menu.c
index d12d0dc3..75433306 100644
--- a/src/hexen/mn_menu.c
+++ b/src/hexen/mn_menu.c
@@ -685,7 +685,7 @@ static boolean ReadDescriptionForSlot(int slot, char *description)
     char name[100];
     char versionText[HXS_VERSION_TEXT_LENGTH];
 
-    snprintf(name, sizeof(name), "%shex%d.hxs", SavePath, slot);
+    M_snprintf(name, sizeof(name), "%shex%d.hxs", SavePath, slot);
 
     fp = fopen(name, "rb");
 
diff --git a/src/hexen/p_acs.c b/src/hexen/p_acs.c
index a9e64517..7ae6a985 100644
--- a/src/hexen/p_acs.c
+++ b/src/hexen/p_acs.c
@@ -443,8 +443,8 @@ boolean P_StartACS(int number, int map, byte * args, mobj_t * activator,
     if (infoIndex == -1)
     {                           // Script not found
         //I_Error("P_StartACS: Unknown script number %d", number);
-        snprintf(ErrorMsg, sizeof(ErrorMsg),
-                 "P_STARTACS ERROR: UNKNOWN SCRIPT %d", number);
+        M_snprintf(ErrorMsg, sizeof(ErrorMsg),
+                   "P_STARTACS ERROR: UNKNOWN SCRIPT %d", number);
         P_SetMessage(&players[consoleplayer], ErrorMsg, true);
     }
     statePtr = &ACSInfo[infoIndex].state;
@@ -540,8 +540,8 @@ boolean P_StartLockedACS(line_t * line, byte * args, mobj_t * mo, int side)
     {
         if (!(mo->player->keys & (1 << (lock - 1))))
         {
-            snprintf(LockedBuffer, sizeof(LockedBuffer),
-                     "YOU NEED THE %s\n", TextKeyMessages[lock - 1]);
+            M_snprintf(LockedBuffer, sizeof(LockedBuffer),
+                       "YOU NEED THE %s\n", TextKeyMessages[lock - 1]);
             P_SetMessage(mo->player, LockedBuffer, true);
             S_StartSound(mo, SFX_DOOR_LOCKED);
             return false;
@@ -1692,7 +1692,7 @@ static int CmdPrintNumber(void)
 {
     char tempStr[16];
 
-    snprintf(tempStr, sizeof(tempStr), "%d", Pop());
+    M_snprintf(tempStr, sizeof(tempStr), "%d", Pop());
     M_StringConcat(PrintBuffer, tempStr, sizeof(PrintBuffer));
     return SCRIPT_CONTINUE;
 }
diff --git a/src/hexen/p_setup.c b/src/hexen/p_setup.c
index cd075651..181e19fe 100644
--- a/src/hexen/p_setup.c
+++ b/src/hexen/p_setup.c
@@ -700,7 +700,7 @@ void P_SetupLevel(int episode, int map, int playermask, skill_t skill)
     P_InitThinkers();
     leveltime = 0;
 
-    snprintf(lumpname, sizeof(lumpname), "MAP%02d", map);
+    M_snprintf(lumpname, sizeof(lumpname), "MAP%02d", map);
     lumpnum = W_GetNumForName(lumpname);
     //
     // Begin processing map lumps
diff --git a/src/hexen/p_spec.c b/src/hexen/p_spec.c
index 06a4a6ff..58f3defe 100644
--- a/src/hexen/p_spec.c
+++ b/src/hexen/p_spec.c
@@ -27,6 +27,7 @@
 
 #include "h2def.h"
 #include "i_system.h"
+#include "m_misc.h"
 #include "p_local.h"
 #include "s_sound.h"
 
@@ -428,8 +429,8 @@ static boolean CheckedLockedDoor(mobj_t * mo, byte lock)
     }
     if (!(mo->player->keys & (1 << (lock - 1))))
     {
-        snprintf(LockedBuffer, sizeof(LockedBuffer),
-                 "YOU NEED THE %s\n", TextKeyMessages[lock - 1]);
+        M_snprintf(LockedBuffer, sizeof(LockedBuffer),
+                   "YOU NEED THE %s\n", TextKeyMessages[lock - 1]);
         P_SetMessage(mo->player, LockedBuffer, true);
         S_StartSound(mo, SFX_DOOR_LOCKED);
         return false;
diff --git a/src/hexen/sb_bar.c b/src/hexen/sb_bar.c
index b35c1f51..5d2438aa 100644
--- a/src/hexen/sb_bar.c
+++ b/src/hexen/sb_bar.c
@@ -640,20 +640,20 @@ static void DrawSoundInfo(void)
             MN_DrTextA("------", xPos[0], y);
             continue;
         }
-        snprintf(text, sizeof(text), "%s", c->name);
+        M_snprintf(text, sizeof(text), "%s", c->name);
         M_ForceUppercase(text);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", c->mo->type);
+        M_snprintf(text, sizeof(text), "%d", c->mo->type);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", c->mo->x >> FRACBITS);
+        M_snprintf(text, sizeof(text), "%d", c->mo->x >> FRACBITS);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", c->mo->y >> FRACBITS);
+        M_snprintf(text, sizeof(text), "%d", c->mo->y >> FRACBITS);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", (int) c->id);
+        M_snprintf(text, sizeof(text), "%d", (int) c->id);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", c->priority);
+        M_snprintf(text, sizeof(text), "%d", c->priority);
         MN_DrTextA(text, xPos[x++], y);
-        snprintf(text, sizeof(text), "%d", c->distance);
+        M_snprintf(text, sizeof(text), "%d", c->distance);
         MN_DrTextA(text, xPos[x++], y);
     }
     UpdateState |= I_FULLSCRN;
@@ -1738,7 +1738,7 @@ static void CheatWarpFunc(player_t * player, Cheat_t * cheat)
         P_SetMessage(player, TXT_CHEATBADINPUT, true);
         return;
     }
-    snprintf(mapName, sizeof(mapName), "MAP%02d", map);
+    M_snprintf(mapName, sizeof(mapName), "MAP%02d", map);
     if (W_CheckNumForName(mapName) == -1)
     {                       // Can't find
         P_SetMessage(player, TXT_CHEATNOMAP, true);
@@ -1769,7 +1769,7 @@ static void CheatMassacreFunc(player_t * player, Cheat_t * cheat)
     char buffer[80];
 
     count = P_Massacre();
-    snprintf(buffer, sizeof(buffer), "%d MONSTERS KILLED\n", count);
+    M_snprintf(buffer, sizeof(buffer), "%d MONSTERS KILLED\n", count);
     P_SetMessage(player, buffer, true);
 }
 
@@ -1857,12 +1857,12 @@ static void CheatVersionFunc(player_t * player, Cheat_t * cheat)
 static void CheatDebugFunc(player_t * player, Cheat_t * cheat)
 {
     char textBuffer[50];
-    snprintf(textBuffer, sizeof(textBuffer),
-             "MAP %d (%d)  X:%5d  Y:%5d  Z:%5d",
-             P_GetMapWarpTrans(gamemap),
-             gamemap,
-             player->mo->x >> FRACBITS,
-             player->mo->y >> FRACBITS, player->mo->z >> FRACBITS);
+    M_snprintf(textBuffer, sizeof(textBuffer),
+               "MAP %d (%d)  X:%5d  Y:%5d  Z:%5d",
+               P_GetMapWarpTrans(gamemap),
+               gamemap,
+               player->mo->x >> FRACBITS,
+               player->mo->y >> FRACBITS, player->mo->z >> FRACBITS);
     P_SetMessage(player, textBuffer, true);
 }
 
@@ -1897,8 +1897,8 @@ static void CheatScriptFunc3(player_t * player, Cheat_t * cheat)
 
     if (P_StartACS(script, 0, script_args, player->mo, NULL, 0))
     {
-        snprintf(textBuffer, sizeof(textBuffer),
-                 "RUNNING SCRIPT %.2d", script);
+        M_snprintf(textBuffer, sizeof(textBuffer),
+                   "RUNNING SCRIPT %.2d", script);
         P_SetMessage(player, textBuffer, true);
     }
 }
@@ -1930,8 +1930,8 @@ static void CheatTrackFunc1(player_t * player, Cheat_t * cheat)
         P_SetMessage(player, "ERROR INITIALIZING CD", true);
     }
 
-    snprintf(buffer, sizeof(buffer), "ENTER DESIRED CD TRACK (%.2d - %.2d):\n",
-            I_CDMusFirstTrack(), I_CDMusLastTrack());
+    M_snprintf(buffer, sizeof(buffer), "ENTER DESIRED CD TRACK (%.2d - %.2d):\n",
+               I_CDMusFirstTrack(), I_CDMusLastTrack());
     P_SetMessage(player, buffer, true);
 }
 
@@ -1968,14 +1968,14 @@ static void CheatTrackFunc2(player_t * player, Cheat_t * cheat)
 
     if (!S_StartCustomCDTrack(track))
     {
-        snprintf(buffer, sizeof(buffer),
-                 "ERROR WHILE TRYING TO PLAY CD TRACK: %.2d\n", track);
+        M_snprintf(buffer, sizeof(buffer),
+                   "ERROR WHILE TRYING TO PLAY CD TRACK: %.2d\n", track);
         P_SetMessage(player, buffer, true);
     }
     else
     {
         // No error encountered while attempting to play the track
-        snprintf(buffer, sizeof(buffer), "PLAYING TRACK: %.2d\n", track);
+        M_snprintf(buffer, sizeof(buffer), "PLAYING TRACK: %.2d\n", track);
         P_SetMessage(player, buffer, true);
     }
 }
diff --git a/src/hexen/sc_man.c b/src/hexen/sc_man.c
index 35f5ec0b..bf3574c3 100644
--- a/src/hexen/sc_man.c
+++ b/src/hexen/sc_man.c
@@ -88,7 +88,7 @@ void SC_Open(char *name)
 
     if (sc_FileScripts == true)
     {
-        snprintf(fileName, sizeof(fileName), "%s%s.txt", sc_ScriptsDir, name);
+        M_snprintf(fileName, sizeof(fileName), "%s%s.txt", sc_ScriptsDir, name);
         SC_OpenFile(fileName);
     }
     else
diff --git a/src/hexen/sv_save.c b/src/hexen/sv_save.c
index dd707398..1aecc5cc 100644
--- a/src/hexen/sv_save.c
+++ b/src/hexen/sv_save.c
@@ -1940,7 +1940,7 @@ void SV_SaveGame(int slot, char *description)
     unsigned int i;
 
     // Open the output file
-    snprintf(fileName, sizeof(fileName), "%shex6.hxs", SavePath);
+    M_snprintf(fileName, sizeof(fileName), "%shex6.hxs", SavePath);
     OpenStreamOut(fileName);
 
     // Write game save description
@@ -2000,7 +2000,7 @@ void SV_SaveMap(boolean savePlayers)
     SavingPlayers = savePlayers;
 
     // Open the output file
-    snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
+    M_snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
     OpenStreamOut(fileName);
 
     // Place a header marker
@@ -2048,7 +2048,7 @@ void SV_LoadGame(int slot)
     }
 
     // Create the name
-    snprintf(fileName, sizeof(fileName), "%shex6.hxs", SavePath);
+    M_snprintf(fileName, sizeof(fileName), "%shex6.hxs", SavePath);
 
     // Load the file
     M_ReadFile(fileName, &SaveBuffer);
@@ -2192,7 +2192,7 @@ void SV_MapTeleport(int map, int position)
     TargetPlayerAddrs = NULL;
 
     gamemap = map;
-    snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
+    M_snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
     if (!deathmatch && ExistingFile(fileName))
     {                           // Unarchive map
         SV_LoadMap();
@@ -2342,7 +2342,7 @@ boolean SV_RebornSlotAvailable(void)
 {
     char fileName[100];
 
-    snprintf(fileName, sizeof(fileName), "%shex%d.hxs", SavePath, REBORN_SLOT);
+    M_snprintf(fileName, sizeof(fileName), "%shex%d.hxs", SavePath, REBORN_SLOT);
     return ExistingFile(fileName);
 }
 
@@ -2363,7 +2363,7 @@ void SV_LoadMap(void)
     RemoveAllThinkers();
 
     // Create the name
-    snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
+    M_snprintf(fileName, sizeof(fileName), "%shex6%02d.hxs", SavePath, gamemap);
 
     // Load the file
     M_ReadFile(fileName, &SaveBuffer);
@@ -3204,11 +3204,11 @@ static void ClearSaveSlot(int slot)
 
     for (i = 0; i < MAX_MAPS; i++)
     {
-        snprintf(fileName, sizeof(fileName),
-                 "%shex%d%02d.hxs", SavePath, slot, i);
+        M_snprintf(fileName, sizeof(fileName),
+                   "%shex%d%02d.hxs", SavePath, slot, i);
         remove(fileName);
     }
-    snprintf(fileName, sizeof(fileName), "%shex%d.hxs", SavePath, slot);
+    M_snprintf(fileName, sizeof(fileName), "%shex%d.hxs", SavePath, slot);
     remove(fileName);
 }
 
@@ -3228,21 +3228,21 @@ static void CopySaveSlot(int sourceSlot, int destSlot)
 
     for (i = 0; i < MAX_MAPS; i++)
     {
-        snprintf(sourceName, sizeof(sourceName),
-                 "%shex%d%02d.hxs", SavePath, sourceSlot, i);
+        M_snprintf(sourceName, sizeof(sourceName),
+                   "%shex%d%02d.hxs", SavePath, sourceSlot, i);
         if (ExistingFile(sourceName))
         {
-            snprintf(destName, sizeof(destName),
-                     "%shex%d%02d.hxs", SavePath, destSlot, i);
+            M_snprintf(destName, sizeof(destName),
+                       "%shex%d%02d.hxs", SavePath, destSlot, i);
             CopyFile(sourceName, destName);
         }
     }
-    snprintf(sourceName, sizeof(sourceName),
-             "%shex%d.hxs", SavePath, sourceSlot);
+    M_snprintf(sourceName, sizeof(sourceName),
+               "%shex%d.hxs", SavePath, sourceSlot);
     if (ExistingFile(sourceName))
     {
-        snprintf(destName, sizeof(destName),
-                 "%shex%d.hxs", SavePath, destSlot);
+        M_snprintf(destName, sizeof(destName),
+                   "%shex%d.hxs", SavePath, destSlot);
         CopyFile(sourceName, destName);
     }
 }