[cfe-dev] sprintf -> snprintf conversion

[Vladimir Kirillov]

Hello, cfe-dev!

I'm using LLVM/Clang on OpenBSD. This project proactively advocates
usage of 'secure' C apis, especially related to memory bounds
checking. Thus using functions like sprintf/strcpy/etc usually spits
out a linker warning in base toolchain:

/home/proger/dev/llvm/Debug+Asserts/lib/libclangFrontend.a(DocumentXML.o)(.text+0xc65): In function `clang::DocumentXML::escapeString(char const*, unsigned long)':
/home/proger/dev/llvm/tools/clang/lib/Frontend/DocumentXML.cpp:107: warning: sprintf() is often misused, please use snprintf()

I've done some conversions from sprintf to snprintf, please commit those.

Thanks!
-------------- next part --------------
Index: include/llvm/ADT/StringExtras.h
===================================================================
--- include/llvm/ADT/StringExtras.h	(revision 117247)
+++ include/llvm/ADT/StringExtras.h	(working copy)
@@ -102,7 +102,7 @@
 
 static inline std::string ftostr(double V) {
   char Buffer[200];
-  sprintf(Buffer, "%20.6e", V);
+  snprintf(Buffer, sizeof(Buffer), "%20.6e", V);
   char *B = Buffer;
   while (*B == ' ') ++B;
   return B;
Index: lib/System/Errno.cpp
===================================================================
--- lib/System/Errno.cpp	(revision 117247)
+++ lib/System/Errno.cpp	(working copy)
@@ -63,7 +63,7 @@
 #else
   // Strange that this system doesn't even have strerror
   // but, oh well, just use a generic message
-  sprintf(buffer, "Error #%d", errnum);
+  snprintf(buffer, sizeof(buffer), "Error #%d", errnum);
 #endif
   return str;
 }
Index: tools/clang/lib/Lex/PPMacroExpansion.cpp
===================================================================
--- tools/clang/lib/Lex/PPMacroExpansion.cpp	(revision 117247)
+++ tools/clang/lib/Lex/PPMacroExpansion.cpp	(working copy)
@@ -482,8 +482,8 @@
     "Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"
   };
 
-  char TmpBuffer[100];
-  sprintf(TmpBuffer, "\"%s %2d %4d\"", Months[TM->tm_mon], TM->tm_mday,
+  char TmpBuffer[32];
+  snprintf(TmpBuffer, sizeof(TmpBuffer), "\"%s %2d %4d\"", Months[TM->tm_mon], TM->tm_mday,
           TM->tm_year+1900);
 
   Token TmpTok;
@@ -491,7 +491,7 @@
   PP.CreateString(TmpBuffer, strlen(TmpBuffer), TmpTok);
   DATELoc = TmpTok.getLocation();
 
-  sprintf(TmpBuffer, "\"%02d:%02d:%02d\"", TM->tm_hour, TM->tm_min, TM->tm_sec);
+  snprintf(TmpBuffer, sizeof(TmpBuffer), "\"%02d:%02d:%02d\"", TM->tm_hour, TM->tm_min, TM->tm_sec);
   PP.CreateString(TmpBuffer, strlen(TmpBuffer), TmpTok);
   TIMELoc = TmpTok.getLocation();
 }
Index: lib/Archive/ArchiveWriter.cpp
===================================================================
--- lib/Archive/ArchiveWriter.cpp	(revision 117247)
+++ lib/Archive/ArchiveWriter.cpp	(working copy)
@@ -82,16 +82,16 @@
   // Set the permissions mode, uid and gid
   hdr.init();
   char buffer[32];
-  sprintf(buffer, "%-8o", mbr.getMode());
+  snprintf(buffer, sizeof(buffer), "%-8o", mbr.getMode());
   memcpy(hdr.mode,buffer,8);
-  sprintf(buffer,  "%-6u", mbr.getUser());
+  snprintf(buffer, sizeof(buffer), "%-6u", mbr.getUser());
   memcpy(hdr.uid,buffer,6);
-  sprintf(buffer,  "%-6u", mbr.getGroup());
+  snprintf(buffer, sizeof(buffer), "%-6u", mbr.getGroup());
   memcpy(hdr.gid,buffer,6);
 
   // Set the last modification date
   uint64_t secondsSinceEpoch = mbr.getModTime().toEpochTime();
-  sprintf(buffer,"%-12u", unsigned(secondsSinceEpoch));
+  snprintf(buffer, sizeof(buffer), "%-12u", unsigned(secondsSinceEpoch));
   memcpy(hdr.date,buffer,12);
 
   // Get rid of trailing blanks in the name
@@ -141,9 +141,9 @@
   // Set the size field
   if (sz < 0) {
     buffer[0] = '-';
-    sprintf(&buffer[1],"%-9u",(unsigned)-sz);
+    snprintf(&buffer[1], sizeof(buffer) - 1, "%-9u", (unsigned)-sz);
   } else {
-    sprintf(buffer, "%-10u", (unsigned)sz);
+    snprintf(buffer, sizeof(buffer), "%-10u", (unsigned)sz);
   }
   memcpy(hdr.size,buffer,10);
 
@@ -290,16 +290,16 @@
   memcpy(Hdr.name,ARFILE_LLVM_SYMTAB_NAME,16);
   uint64_t secondsSinceEpoch = sys::TimeValue::now().toEpochTime();
   char buffer[32];
-  sprintf(buffer, "%-8o", 0644);
-  memcpy(Hdr.mode,buffer,8);
-  sprintf(buffer, "%-6u", sys::Process::GetCurrentUserId());
-  memcpy(Hdr.uid,buffer,6);
-  sprintf(buffer, "%-6u", sys::Process::GetCurrentGroupId());
-  memcpy(Hdr.gid,buffer,6);
-  sprintf(buffer,"%-12u", unsigned(secondsSinceEpoch));
-  memcpy(Hdr.date,buffer,12);
-  sprintf(buffer,"%-10u",symTabSize);
-  memcpy(Hdr.size,buffer,10);
+  snprintf(buffer, sizeof(buffer), "%-8o", 0644);
+  memcpy(Hdr.mode,buffer, 8);
+  snprintf(buffer, sizeof(buffer), "%-6u", sys::Process::GetCurrentUserId());
+  memcpy(Hdr.uid,buffer, 6);
+  snprintf(buffer, sizeof(buffer), "%-6u", sys::Process::GetCurrentGroupId());
+  memcpy(Hdr.gid,buffer, 6);
+  snprintf(buffer, sizeof(buffer), "%-12u", unsigned(secondsSinceEpoch));
+  memcpy(Hdr.date,buffer, 12);
+  snprintf(buffer, sizeof(buffer), "%-10u",symTabSize);
+  memcpy(Hdr.size,buffer, 10);
 
   // Write the header
   ARFile.write((char*)&Hdr, sizeof(Hdr));
Index: lib/Target/CBackend/CBackend.cpp
===================================================================
--- lib/Target/CBackend/CBackend.cpp	(revision 117247)
+++ lib/Target/CBackend/CBackend.cpp	(working copy)
@@ -746,7 +746,7 @@
     APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, &ignored);
 #if HAVE_PRINTF_A && ENABLE_CBE_PRINTF_A
   char Buffer[100];
-  sprintf(Buffer, "%a", APF.convertToDouble());
+  snprintf(Buffer, sizeof(Buffer), "%a", APF.convertToDouble());
   if (!strncmp(Buffer, "0x", 2) ||
       !strncmp(Buffer, "-0x", 3) ||
       !strncmp(Buffer, "+0x", 3))
@@ -1072,7 +1072,7 @@
         char Buffer[100];
 
         uint64_t ll = DoubleToBits(V);
-        sprintf(Buffer, "0x%llx", static_cast<long long>(ll));
+        snprintf(Buffer, sizeof(Buffer), "0x%llx", static_cast<long long>(ll));
 
         std::string Num(&Buffer[0], &Buffer[6]);
         unsigned long Val = strtoul(Num.c_str(), 0, 16);
@@ -1094,7 +1094,7 @@
 #if HAVE_PRINTF_A && ENABLE_CBE_PRINTF_A
         // Print out the constant as a floating point number.
         char Buffer[100];
-        sprintf(Buffer, "%a", V);
+        snprintf(Buffer, sizeof(Buffer), "%a", V);
         Num = Buffer;
 #else
         Num = ftostr(FPC->getValueAPF());
@@ -1343,7 +1343,7 @@
     if (!((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') ||
           (ch >= '0' && ch <= '9') || ch == '_')) {
       char buffer[5];
-      sprintf(buffer, "_%x_", ch);
+      snprintf(buffer, sizeof(buffer), "_%x_", ch);
       VarName += buffer;
     } else
       VarName += ch;
Index: lib/Target/CppBackend/CPPBackend.cpp
===================================================================
--- lib/Target/CppBackend/CPPBackend.cpp	(revision 117247)
+++ lib/Target/CppBackend/CPPBackend.cpp	(working copy)
@@ -224,7 +224,7 @@
   Out << "APFloat(";
 #if HAVE_PRINTF_A
   char Buffer[100];
-  sprintf(Buffer, "%A", APF.convertToDouble());
+  snprintf(Buffer, sizeof(Buffer), "%A", APF.convertToDouble());
   if ((!strncmp(Buffer, "0x", 2) ||
        !strncmp(Buffer, "-0x", 3) ||
        !strncmp(Buffer, "+0x", 3)) &&