X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/86948c99a6f0fd177b09b3db0ef702739ec62a27..cc1487e53905bd534dba2099d33ac2142cec7818:/src/common/textfile.cpp?ds=sidebyside

diff --git a/src/common/textfile.cpp b/src/common/textfile.cpp
index b7ab9e06ca..3334375b44 100644
--- a/src/common/textfile.cpp
+++ b/src/common/textfile.cpp
@@ -35,6 +35,7 @@
 
 #include "wx/textfile.h"
 #include "wx/filename.h"
+#include "wx/buffer.h"
 
 // ============================================================================
 // wxTextFile class implementation
@@ -85,20 +86,27 @@ bool wxTextFile::OnClose()
 }
 
 
-bool wxTextFile::OnRead(wxMBConv& conv)
+bool wxTextFile::OnRead(const wxMBConv& conv)
 {
     // file should be opened and we must be in it's beginning
-    wxASSERT( m_file.IsOpened() &&
-                (m_file.GetKind() != wxFILE_KIND_DISK || m_file.Tell() == 0) );
-
-    char buf[1025];
-    wxChar chLast = '\0';
-    wxString str;
-
-    for ( ;; )
+    wxASSERT( m_file.IsOpened() && m_file.Tell() == 0 );
+
+    // read the entire file in memory: this is not the most efficient thing to
+    // do but there is no good way to avoid it in Unicode build because if we
+    // read the file block by block we can't convert each block to Unicode
+    // separately (the last multibyte char in the block might be only partially
+    // read and so the conversion would fail) and, as the file contents is kept
+    // in memory by wxTextFile anyhow, it shouldn't be a big problem to read
+    // the file entirely
+    const size_t bufSize = (size_t)(m_file.Length() + 4 /* for trailing NULs */ );
+    size_t bufPos = 0;
+    wxCharBuffer buf(bufSize - 1 /* it adds 1 internally */);
+
+    char block[1024];
+    for ( bool eof = false; !eof; )
     {
-        // leave space for trailing NUL
-        ssize_t nRead = m_file.Read(buf, WXSIZEOF(buf) - 1);
+        // try to read up to the size of the entire block
+        ssize_t nRead = m_file.Read(block, WXSIZEOF(block));
 
         if ( nRead == wxInvalidOffset )
         {
@@ -109,71 +117,91 @@ bool wxTextFile::OnRead(wxMBConv& conv)
         if ( nRead == 0 )
             break;
 
-        buf[nRead] = '\0';
+        // this shouldn't happen but don't overwrite the buffer if it does
+        wxCHECK_MSG( bufPos + nRead <= bufSize, false,
+                     _T("read more than file length?") );
 
-        // append to the remains of the last block, don't overwrite
-        str += wxString(buf, conv);
+        // append to the buffer
+        memcpy(buf.data() + bufPos, block, nRead);
+        bufPos += nRead;
+    }
 
-        // the beginning of the current line, changes inside the loop
-        const wxChar *lineStart = str.begin();
-        const wxChar * const end = str.end();
-        for ( const wxChar *p = lineStart; p != end; p++ )
-        {
-            const wxChar ch = *p;
-            switch ( ch )
-            {
-                case '\n':
-                    // could be a DOS or Unix EOL
-                    if ( chLast == '\r' )
-                    {
-                        AddLine(wxString(lineStart, p - 1), wxTextFileType_Dos);
-                    }
-                    else // bare '\n', Unix style
-                    {
-                        AddLine(wxString(lineStart, p), wxTextFileType_Unix);
-                    }
+    const wxString str(buf, conv, bufPos);
+
+    // this doesn't risk to happen in ANSI build
+#if wxUSE_UNICODE
+    if ( bufSize > 4 && str.empty() )
+    {
+        wxLogError(_("Failed to convert file contents to Unicode."));
+        return false;
+    }
+#endif // wxUSE_UNICODE
 
+    free(buf.release()); // we don't need this memory any more
+
+
+    // now break the buffer in lines
+
+    // last processed character, we need to know if it was a CR or not
+    wxChar chLast = '\0';
+
+    // the beginning of the current line, changes inside the loop
+    wxString::const_iterator lineStart = str.begin();
+    const wxString::const_iterator end = str.end();
+    for ( wxString::const_iterator p = lineStart; p != end; p++ )
+    {
+        const wxChar ch = *p;
+        switch ( ch )
+        {
+            case '\n':
+                // could be a DOS or Unix EOL
+                if ( chLast == '\r' )
+                {
+                    AddLine(wxString(lineStart, p - 1), wxTextFileType_Dos);
+                }
+                else // bare '\n', Unix style
+                {
+                    AddLine(wxString(lineStart, p), wxTextFileType_Unix);
+                }
+
+                lineStart = p + 1;
+                break;
+
+            case '\r':
+                if ( chLast == '\r' )
+                {
+                    // Mac empty line
+                    AddLine(wxEmptyString, wxTextFileType_Mac);
                     lineStart = p + 1;
-                    break;
-
-                case '\r':
-                    if ( chLast == '\r' )
-                    {
-                        // Mac empty line
-                        AddLine(wxEmptyString, wxTextFileType_Mac);
-                        lineStart = p + 1;
-                    }
-                    //else: we don't what this is yet -- could be a Mac EOL or
-                    //      start of DOS EOL so wait for next char
-                    break;
-
-                default:
-                    if ( chLast == '\r' )
-                    {
-                        // Mac line termination
-                        AddLine(wxString(lineStart, p - 1), wxTextFileType_Mac);
-                        lineStart = p;
-                    }
-            }
-
-            chLast = ch;
+                }
+                //else: we don't know what this is yet -- could be a Mac EOL or
+                //      start of DOS EOL so wait for next char
+                break;
+
+            default:
+                if ( chLast == '\r' )
+                {
+                    // Mac line termination
+                    AddLine(wxString(lineStart, p - 1), wxTextFileType_Mac);
+                    lineStart = p;
+                }
         }
 
-        // remove the part we already processed
-        str.erase(0, lineStart - str.begin());
+        chLast = ch;
     }
 
     // anything in the last line?
-    if ( !str.empty() )
+    if ( lineStart != end )
     {
-        AddLine(str, wxTextFileType_None); // no line terminator
+        // add unterminated last line
+        AddLine(wxString(lineStart, end), wxTextFileType_None);
     }
 
     return true;
 }
 
 
-bool wxTextFile::OnWrite(wxTextFileType typeNew, wxMBConv& conv)
+bool wxTextFile::OnWrite(wxTextFileType typeNew, const wxMBConv& conv)
 {
     wxFileName fn = m_strBufferName;
 
@@ -203,4 +231,3 @@ bool wxTextFile::OnWrite(wxTextFileType typeNew, wxMBConv& conv)
 }
 
 #endif // wxUSE_TEXTFILE
-