[lldb] Replace sprintf with snprintf (NFC)

[kastiglione]

Summary

On macOS, sprintf is deprecated, using snprintf is recommended instead.

[JDevlieghere]

This looks fine, but I wonder if using llvm::formatv wouldn't make this a whole lot easier?

[kastiglione]

That may be better, I don't really know. I would prefer to merge this as is (and leave a printf->formatv migration for another time).

[JDevlieghere]

Ship it

lldb/source/Core/SourceManager.cpp

for (uint32_t line = start_line; line <= end_line; ++line) {
 
         if (bp_count > 0)
           prefix = llvm::formatv("[{0}]", bp_count);
         else
           prefix = "    ";
       }
 
       char buffer[3];
-      sprintf(buffer, "%2.2s", (line == curr_line) ? current_line_cstr : "");
+      snprintf(buffer, sizeof(buffer), "%2.2s",
+               (line == curr_line) ? current_line_cstr : "");
       std::string current_line_highlight(buffer);
 
       auto debugger_sp = m_debugger_wp.lock();
       if (should_show_stop_line_with_ansi(debugger_sp)) {
         current_line_highlight = ansi::FormatAnsiTerminalCodes(
             (debugger_sp->GetStopShowLineMarkerAnsiPrefix() +
              current_line_highlight +
              debugger_sp->GetStopShowLineMarkerAnsiSuffix())

lldb/source/DataFormatters/StringPrinter.cpp

if (llvm::isPrint(*buffer))
     return {buffer, 1};
 
   unsigned escaped_len;
   constexpr unsigned max_buffer_size = 7;
   uint8_t data[max_buffer_size];
   switch (escape_style) {
   case StringPrinter::EscapeStyle::CXX:
     // Prints 4 characters, then a \0 terminator.
-    escaped_len = sprintf((char *)data, "\\x%02x", *buffer);
+    escaped_len = snprintf((char *)data, max_buffer_size, "\\x%02x", *buffer);
     break;
   case StringPrinter::EscapeStyle::Swift:
     // Prints up to 6 characters, then a \0 terminator.
-    escaped_len = sprintf((char *)data, "\\u{%x}", *buffer);
+    escaped_len = snprintf((char *)data, max_buffer_size, "\\u{%x}", *buffer);
     break;
   }
   lldbassert(escaped_len > 0 && "unknown string escape style");
   return {data, escaped_len};
 }
 
 template <>
 DecodedCharBuffer GetPrintableImpl<StringElementType::UTF8>(
if (isprint32(codepoint))
     return {buffer, utf8_encoded_len};
 
   unsigned escaped_len;
   constexpr unsigned max_buffer_size = 13;
   uint8_t data[max_buffer_size];
   switch (escape_style) {
   case StringPrinter::EscapeStyle::CXX:
     // Prints 10 characters, then a \0 terminator.
-    escaped_len = sprintf((char *)data, "\\U%08x", codepoint);
+    escaped_len = snprintf((char *)data, max_buffer_size, "\\U%08x", codepoint);
     break;
   case StringPrinter::EscapeStyle::Swift:
     // Prints up to 12 characters, then a \0 terminator.
-    escaped_len = sprintf((char *)data, "\\u{%x}", codepoint);
+    escaped_len = snprintf((char *)data, max_buffer_size, "\\u{%x}", codepoint);
     break;
   }
   lldbassert(escaped_len > 0 && "unknown string escape style");
   return {data, escaped_len};
 }
 
 // Given a sequence of bytes, this function returns: a sequence of bytes to
 // actually print out + a length the following unscanned position of the buffer

lldb/source/Host/macosx/objcxx/Host.mm

bool Host::GetProcessInfo(lldb::pid_t pid, ProcessInstanceInfo &process_info) {
   return false;
 }
 
 #if TARGET_OS_OSX
 static void PackageXPCArguments(xpc_object_t message, const char *prefix,
                                 const Args &args) {
   size_t count = args.GetArgumentCount();
   char buf[50]; // long enough for 'argXXX'
-  memset(buf, 0, 50);
-  sprintf(buf, "%sCount", prefix);
+  memset(buf, 0, sizeof(buf));
+  snprintf(buf, sizeof(buf), "%sCount", prefix);
   xpc_dictionary_set_int64(message, buf, count);
   for (size_t i = 0; i < count; i++) {
-    memset(buf, 0, 50);
-    sprintf(buf, "%s%zi", prefix, i);
+    memset(buf, 0, sizeof(buf));
+    snprintf(buf, sizeof(buf), "%s%zi", prefix, i);
     xpc_dictionary_set_string(message, buf, args.GetArgumentAtIndex(i));
   }
 }
 
 static void PackageXPCEnvironment(xpc_object_t message, llvm::StringRef prefix,
                                   const Environment &env) {
   xpc_dictionary_set_int64(message, (prefix + "Count").str().c_str(),
                            env.size());