Improve LLFile to be consistent between Windows and Linux/Mac

indra/llcommon/llfile.h

@@ -41,8 +41,8 @@ typedef FILE    LLFILE;
 #include <sys/stat.h>
 
 #if LL_WINDOWS
-// windows version of stat function and stat data structure are called _stat
-typedef struct _stat    llstat;
+// windows version of stat function and stat data structure are called _statxx
+typedef struct _stat64    llstat;
 #else
 typedef struct stat     llstat;
 #include <sys/types.h>
@@ -58,33 +58,89 @@ typedef struct stat     llstat;
 
 #include "llstring.h" // safe char* -> std::string conversion
 
+/// LLFile is a class of static functions operating on paths
+/// All the functions with a path string input take UTF8 path/filenames
 class LL_COMMON_API LLFile
 {
 public:
-    // All these functions take UTF8 path/filenames.
-    static  LLFILE* fopen(const std::string& filename,const char* accessmode);  /* Flawfinder: ignore */
-    static  LLFILE* _fsopen(const std::string& filename,const char* accessmode,int  sharingFlag);
+    /// open a file with the specified access mode
+    static  LLFILE* fopen(const std::string& filename, const char* accessmode);  /* Flawfinder: ignore */
+    ///< 'accessmode' follows the rules of the Posix fopen() mode parameter
+    /// "r" open the file for reading only and positions the stream at the beginning
+    /// "r+" open the file for reading and writing and positions the stream at the beginning
+    /// "w" open the file for reading and writing and truncate it to zero length
+    /// "w+" open or create the file for reading and writing and truncate to zero length if it existed
+    /// "a" open the file for reading and writing and position the stream at the end of the file
+    /// "a+" open or create the file for reading and writing and position the stream at the end of the file
+    ///
+    /// in addition to these values, "b" can be appended to indicate binary stream access, but on Linux and Mac
+    /// this is strictly for compatibility and has no effect. On Windows this makes the file functions not
+    /// try to translate line endings. Windows also allows to append "t" to indicate text mode. If neither
+    /// "b" or "t" is defined, Windows uses the value set by _fmode which by default is _O_TEXT.
+    /// This means that it is always a good idea to append "b" specifically for binary file access to
+    /// avoid corruption of the binary consistency of the data stream when reading or writing
+    /// Other characters in 'accessmode' will usually cause an error as fopen will verify this parameter
+    /// @returns a valid LLFILE* pointer on success or NULL on failure
 
     static  int     close(LLFILE * file);
 
+    /// retrieve the content of a file into a string
     static std::string getContents(const std::string& filename);
+    ///< @returns the content of the file or an empty string on failure
 
-    // perms is a permissions mask like 0777 or 0700.  In most cases it will
-    // be overridden by the user's umask.  It is ignored on Windows.
-    // mkdir() considers "directory already exists" to be SUCCESS.
+    /// create a directory
     static  int     mkdir(const std::string& filename, int perms = 0700);
-
-    static  int     rmdir(const std::string& filename);
+    ///< perms is a permissions mask like 0777 or 0700.  In most cases it will be
+    ///  overridden by the user's umask. It is ignored on Windows.
+    ///  mkdir() considers "directory already exists" to be not an error.
+    ///  @returns 0 on success and -1 on failure.
+
+    //// remove a directory
+    static  int     rmdir(const std::string& filename, int supress_error = 0);
+    ///< pass ENOENT in the optional 'supress_error' parameter
+    ///  if you don't want a warning in the log when the directory does not exist
+    ///  @returns 0 on success and -1 on failure.
+
+    /// remove a file or directory
     static  int     remove(const std::string& filename, int supress_error = 0);
-    static  int     rename(const std::string& filename,const std::string& newname, int supress_error = 0);
-    static  bool    copy(const std::string& from, const std::string& to);
+    ///< pass ENOENT in the optional 'supress_error' parameter
+    ///  if you don't want a warning in the log when the directory does not exist
+    ///  @returns 0 on success and -1 on failure.
 
-    static  int     stat(const std::string& filename,llstat*    file_status);
-    static  bool    isdir(const std::string&    filename);
-    static  bool    isfile(const std::string&   filename);
-    static  LLFILE *    _Fiopen(const std::string& filename,
-            std::ios::openmode mode);
+    /// rename a file
+    static  int     rename(const std::string& filename, const std::string& newname, int supress_error = 0);
+    ///< it will silently overwrite newname if it exists without returning an error
+    ///  @returns 0 on success and -1 on failure.
 
+
+    // copy the contents of file from 'from' to 'to' filename
+    static  bool    copy(const std::string& from, const std::string& to);
+    ///< @returns true on success and false on failure.
+
+    /// return the file stat structure for filename
+    static  int     stat(const std::string& filename, llstat* file_status, int supress_error = ENOENT);
+    ///< for compatibility with existing uses of LL_File::stat() we use ENOENT as default in the
+    ///  optional 'supress_error' parameter to avoid spamming the log with warnings when the API
+    ///  is used to detect if a file exists
+    ///  @returns 0 on success and -1 on failure.
+
+    /// get the file or directory attributes for filename
+    static  unsigned short getattr(const std::string& filename, int supress_error = 0);
+    ///< a more lightweight function on Windows to stat, that just returns the file attribute flags
+    ///  pass ENOENT in the optional 'supress_error' parameter if you don't want a warning
+    ///  in the log when the file or directory does not exist
+    ///  @returns 0 on failure and a st_mode value with either S_IFDIR or S_IFREG set otherwise
+    ///  together with the three access bits which under Windows only the write bit is relevant.
+
+    /// check if filename is an existing directory
+    static  bool    isdir(const std::string& filename);
+    ///< @returns true if the path is for an existing directory
+
+    /// check if filename is an existing file
+    static  bool    isfile(const std::string& filename);
+    ///< @returns true if the path is for an existing file
+
+    /// return a path to the temporary directory on the system
     static  const char * tmpdir();
 };
 

indra/llcommon/llsys.cpp

@@ -1348,10 +1348,6 @@ bool gunzip_file(const std::string& srcfile, const std::string& dstfile)
     } while(gzeof(src) == 0);
     fclose(dst);
     dst = NULL;
-#if LL_WINDOWS
-    // Rename in windows needs the dstfile to not exist.
-    LLFile::remove(dstfile, ENOENT);
-#endif
     if (LLFile::rename(tmpfile, dstfile) == -1) goto err;       /* Flawfinder: ignore */
     retval = true;
 err:
@@ -1399,10 +1395,6 @@ bool gzip_file(const std::string& srcfile, const std::string& dstfile)
 
     gzclose(dst);
     dst = NULL;
-#if LL_WINDOWS
-    // Rename in windows needs the dstfile to not exist.
-    LLFile::remove(dstfile);
-#endif
     if (LLFile::rename(tmpfile, dstfile) == -1) goto err;       /* Flawfinder: ignore */
     retval = true;
  err:

indra/llcrashlogger/llcrashlogger.cpp

@@ -576,10 +576,6 @@ bool LLCrashLogger::init()
     std::string old_log_file = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "crashreport.log.old");
     std::string log_file = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "crashreport.log");
 
-#if LL_WINDOWS
-    LLAPRFile::remove(old_log_file);
-#endif
-
     LLFile::rename(log_file.c_str(), old_log_file.c_str());
 
     // Set the log file to crashreport.log

indra/llfilesystem/llfilesystem.cpp

@@ -103,9 +103,6 @@ bool LLFileSystem::renameFile(const LLUUID& old_file_id, const LLAssetType::ETyp
     const std::string old_filename = LLDiskCache::metaDataToFilepath(old_file_id, old_file_type);
     const std::string new_filename = LLDiskCache::metaDataToFilepath(new_file_id, new_file_type);
 
-    // Rename needs the new file to not exist.
-    LLFileSystem::removeFile(new_file_id, new_file_type, ENOENT);
-
     if (LLFile::rename(old_filename, new_filename) != 0)
     {
         // We would like to return false here indicating the operation

indra/llui/llviewereventrecorder.cpp

@@ -34,8 +34,6 @@ LLViewerEventRecorder::LLViewerEventRecorder() {
   logEvents = false;
   // Remove any previous event log file
   std::string old_log_ui_events_to_llsd_file = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "SecondLife_Events_log.old");
-  LLFile::remove(old_log_ui_events_to_llsd_file, ENOENT);
-
 
   mLogFilename = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "SecondLife_Events_log.llsd");
   LLFile::rename(mLogFilename, old_log_ui_events_to_llsd_file, ENOENT);

indra/newview/llappviewer.cpp

@@ -2398,7 +2398,6 @@ void LLAppViewer::initLoggingAndGetLastDuration()
         if (gDirUtilp->fileExists(user_data_path_cef_log))
         {
             std::string user_data_path_cef_old = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "cef.old");
-            LLFile::remove(user_data_path_cef_old, ENOENT);
             LLFile::rename(user_data_path_cef_log, user_data_path_cef_old);
         }
     }

indra/newview/llvoicevivox.cpp

@@ -1014,7 +1014,6 @@ bool LLVivoxVoiceClient::startAndLaunchDaemon()
             std::string old_log = gDirUtilp->getExpandedFilename(LL_PATH_LOGS, "SLVoice.old");
             if (gDirUtilp->fileExists(new_log))
             {
-                LLFile::remove(old_log, ENOENT);
                 LLFile::rename(new_log, old_log);
             }