Fail iconv call gracefully

No freezing when inbuf_size doesn't decrease over time.

diff --git a/src/util/string.cpp b/src/util/string.cpp
index 0a7ab5c3a406856b31507bb79541cd8ecd940dd5..e847f3a8e605f75a80f06c0c46dd0ca28d5c8302 100644 (file)
--- a/src/util/string.cpp
+++ b/src/util/string.cpp
@@ -40,7 +40,7 @@ static bool parseHexColorString(const std::string &value, video::SColor &color);
 static bool parseNamedColorString(const std::string &value, video::SColor &color);
 
 #ifndef _WIN32
-size_t convert(const char *to, const char *from, char *outbuf,
+bool convert(const char *to, const char *from, char *outbuf,
                size_t outbuf_size, char *inbuf, size_t inbuf_size)
 {
        iconv_t cd = iconv_open(to, from);
@@ -56,11 +56,18 @@ size_t convert(const char *to, const char *from, char *outbuf,
        size_t *inbuf_left_ptr = &inbuf_size;
        size_t *outbuf_left_ptr = &outbuf_size;
 
-       while (inbuf_size > 0)
+       size_t old_size = inbuf_size;
+       while (inbuf_size > 0) {
                iconv(cd, &inbuf_ptr, inbuf_left_ptr, &outbuf_ptr, outbuf_left_ptr);
+               if (inbuf_size == old_size) {
+                       iconv_close(cd);
+                       return false;
+               }
+               old_size = inbuf_size;
+       }
 
        iconv_close(cd);
-       return 0;
+       return true;
 }
 
 std::wstring utf8_to_wide(const std::string &input)
@@ -74,7 +81,13 @@ std::wstring utf8_to_wide(const std::string &input)
        char *outbuf = new char[outbuf_size];
        memset(outbuf, 0, outbuf_size);
 
-       convert("WCHAR_T", "UTF-8", outbuf, outbuf_size, inbuf, inbuf_size);
+       if (!convert("WCHAR_T", "UTF-8", outbuf, outbuf_size, inbuf, inbuf_size)) {
+               infostream << "Couldn't convert UTF-8 string 0x" << hex_encode(input)
+                       << " into wstring" << std::endl;
+               delete[] inbuf;
+               delete[] outbuf;
+               return L"<invalid UTF-8 string>";
+       }
        std::wstring out((wchar_t*)outbuf);
 
        delete[] inbuf;
@@ -101,7 +114,13 @@ std::string wide_to_utf8(const std::wstring &input)
        char *outbuf = new char[outbuf_size];
        memset(outbuf, 0, outbuf_size);
 
-       convert("UTF-8", "WCHAR_T", outbuf, outbuf_size, inbuf, inbuf_size);
+       if (!convert("UTF-8", "WCHAR_T", outbuf, outbuf_size, inbuf, inbuf_size)) {
+               infostream << "Couldn't convert wstring 0x" << hex_encode(inbuf, inbuf_size)
+                       << " into wstring" << std::endl;
+               delete[] inbuf;
+               delete[] outbuf;
+               return "<invalid wstring>";
+       }
        std::string out(outbuf);
 
        delete[] inbuf;