Use dynamic buffer sizes for formated CEXEBuild warning/error methods

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@6292 212acab6-be3b-0410-9dea-997c60f758d6

Source/build.cpp

@@ -492,7 +492,9 @@ int CEXEBuild::add_string(const TCHAR *string, int process/*=1*/, UINT codepage/
   int i;
   if (process)
   {
-    TCHAR buf[NSIS_MAX_STRLEN*4];
+    ExpandoString<TCHAR, NSIS_MAX_STRLEN*4> buf;
+    // NOTE: It is impossible to know how much preprocessing will increase the size, we have to guess
+    buf.Reserve(_tcsclen(string) * 2);
     preprocess_string(buf, string, codepage);
     i = cur_strlist->add(buf, (WORD)codepage, true);
   }
@@ -3310,42 +3312,36 @@ bool IsStringASCII(const TCHAR* s)
 
 void CEXEBuild::warning(const TCHAR *s, ...)
 {
-  TCHAR buf[NSIS_MAX_STRLEN*10];
+  ExpandoString<TCHAR, NSIS_MAX_STRLEN + 100> buf;
   va_list val;
   va_start(val,s);
-#ifdef _WIN32
+  buf.StrFmt(s,val);
-  _vstprintf(buf,s,val);
-#else
-  _vsntprintf(buf,NSIS_MAX_STRLEN*10,s,val);
-#endif
   va_end(val);
 
   m_warnings.add(buf,0);
-  notify(MAKENSIS_NOTIFY_WARNING,buf);
+  notify(MAKENSIS_NOTIFY_WARNING,buf.GetPtr());
   if (display_warnings)
   {
-    PrintColorFmtMsg_WARN(_T("warning: %s\n"),buf);
+    PrintColorFmtMsg_WARN(_T("warning: %s\n"),buf.GetPtr());
   }
 }
 
 void CEXEBuild::warning_fl(const TCHAR *s, ...)
 {
-  TCHAR buf[NSIS_MAX_STRLEN*10];
+  ExpandoString<TCHAR, NSIS_MAX_STRLEN + 100> buf;
   va_list val;
   va_start(val,s);
-#ifdef _WIN32
+  size_t cchMsg = buf.StrFmt(s,val);
-  _vstprintf(buf,s,val);
-#else
-  _vsntprintf(buf,NSIS_MAX_STRLEN*10,s,val);
-#endif
   va_end(val);
-  _stprintf(buf+_tcslen(buf),_T(" (%s:%d)"),curfilename,linecnt);
+
+  buf.Reserve(cchMsg+2+_tcslen(curfilename)+50+1+1);
+  _stprintf(&buf[cchMsg],_T(" (%s:%u)"),curfilename,linecnt);
 
   m_warnings.add(buf,0);
-  notify(MAKENSIS_NOTIFY_WARNING,buf);
+  notify(MAKENSIS_NOTIFY_WARNING,buf.GetPtr());
   if (display_warnings)
   {
-    PrintColorFmtMsg_WARN(_T("warning: %s\n"),buf);
+    PrintColorFmtMsg_WARN(_T("warning: %s\n"),buf.GetPtr());
   }
 }
 
@@ -3353,19 +3349,16 @@ void CEXEBuild::ERROR_MSG(const TCHAR *s, ...) const
 {
   if (display_errors || notify_hwnd)
   {
-    TCHAR buf[NSIS_MAX_STRLEN*10];
+    ExpandoString<TCHAR, NSIS_MAX_STRLEN + 100> buf;
     va_list val;
     va_start(val,s);
-#ifdef _WIN32
+    buf.StrFmt(s,val);
-    _vstprintf(buf,s,val);
-#else
-    _vsntprintf(buf,NSIS_MAX_STRLEN*10,s,val);
-#endif
     va_end(val);
-    notify(MAKENSIS_NOTIFY_ERROR,buf);
+
+    notify(MAKENSIS_NOTIFY_ERROR,buf.GetPtr());
     if (display_errors)
     {
-      PrintColorFmtMsg_ERR(_T("%s"),buf);
+      PrintColorFmtMsg_ERR(_T("%s"),buf.GetPtr());
     }
   }
 }

Source/util.cpp

@@ -552,6 +552,67 @@ tstring lowercase(const tstring &str) {
   return result;
 }
 
+/*
+ * ExpandoStrFmtVaList returns the number of characters written excluding
+ * the \0 terminator or 0 on error.
+ * realloc() is used on *ppMalloc if cchStack is not 
+ * large enough to hold the formated string.
+*/
+size_t ExpandoStrFmtVaList(wchar_t*Stack, size_t cchStack, wchar_t**ppMalloc, const wchar_t*FmtStr, va_list Args)
+{
+#ifdef _WIN32
+// For _vsnwprintf, the \0 terminator is not part of the size
+#define ExpandoStrFmtVaList_vsnwprintf(d,c,f,v) _vsnwprintf((d),(c)?(c)-1:0,(f),(v))
+#else
+#define ExpandoStrFmtVaList_vsnwprintf vswprintf
+#endif
+#if defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
+  const bool cansizecalc = true, msvcbackdoor = false;
+#else
+  static char testedsizecalc = 0;
+  if (!testedsizecalc)
+  {
+#ifdef _WIN32
+    size_t cch = ExpandoStrFmtVaList_vsnwprintf(0, INT_MAX, L"333", Args);
+#else
+    wchar_t testbuf[1+1];
+    size_t cch = ExpandoStrFmtVaList_vsnwprintf(testbuf, COUNTOF(testbuf), L"333", Args);
+#endif
+    testedsizecalc = (3 == cch) + 1;
+  }
+#ifdef _WIN32
+  const bool msvcbackdoor = !!(testedsizecalc - 1), cansizecalc = false;
+#else
+  const bool cansizecalc = !!(testedsizecalc - 1), msvcbackdoor = false;
+#endif
+#endif
+  size_t &cchAvail = cchStack, cch;
+  wchar_t *&dest = Stack, *mem = *ppMalloc;
+  for(;;)
+  {
+    cch = ExpandoStrFmtVaList_vsnwprintf(dest, cchAvail, FmtStr, Args);
+    if (-1 == cch)
+    {
+      cch = 0;
+      if (cansizecalc) break; // vswprintf error, abort!
+      if (msvcbackdoor)
+        cchAvail = ExpandoStrFmtVaList_vsnwprintf(0, INT_MAX, FmtStr, Args) + 1;
+      else
+        cchAvail = 4 * STD_MAX(cchAvail, (size_t)500);
+    }
+    else
+    {
+      if (cch < cchAvail) break; // We are done.
+      cchAvail = ++cch; // cch from vswprintf did not include the \0 terminator
+    }
+    dest = mem = (wchar_t*) realloc(mem, cchAvail * sizeof(wchar_t));
+    if (!mem) return 0;
+  }
+  *ppMalloc = mem;
+  return cch;
+}
+
+
 int sane_system(const TCHAR *command) {
 #ifdef _WIN32
 

Source/util.h

@@ -56,6 +56,30 @@ tstring lowercase(const tstring&);
 tstring get_string_prefix(const tstring& str, const tstring& separator);
 tstring get_string_suffix(const tstring& str, const tstring& separator);
 
+size_t ExpandoStrFmtVaList(wchar_t*Stack, size_t cchStack, wchar_t**ppMalloc, const wchar_t*FmtStr, va_list Args);
+
+template<typename T, size_t S> class ExpandoString {
+  T m_stack[S ? S : 1], *m_heap;
+public:
+  ExpandoString() : m_heap(0) {}
+  ~ExpandoString() { free(m_heap); }
+  void Reserve(size_t cch)
+  {
+    if (S && cch <= S) return ;
+    void *p = realloc(m_heap, cch * sizeof(T));
+    if (!p) throw std::bad_alloc();
+    m_heap = (T*) p;
+  }
+  size_t StrFmt(const T*FmtStr, va_list Args)
+  {
+    size_t n = ExpandoStrFmtVaList(m_stack, COUNTOF(m_stack), &m_heap, FmtStr, Args);
+    if (!n && *FmtStr) throw std::bad_alloc();
+    return n;
+  }
+  T* GetPtr() { return m_heap ? m_heap : m_stack; }
+  operator T*() { return GetPtr(); }
+};
+
 int sane_system(const TCHAR *command);
 
 void PrintColorFmtMsg(unsigned int type, const TCHAR *fmtstr, va_list args);