/* External utility functions for Modelica packages
   Modelica_Utilities.Internal

   The functions are mostly non-portable. The following #define's are used
   to define the system calls of the operating system

    _WIN32         : System calls of Windows'95, Windows'NT
                     (Note, that these system calls allow both '/' and '\'
                     as directory separator for input arguments. As return
                     argument '\' is used).
                     All system calls are from the library libc.a.
    _POSIX_        : System calls of POSIX
    _MSC_VER       : Microsoft Visual C++
    __GNUC__       : GNU C compiler
    NO_FILE_SYSTEM : A file system is not present (e.g. on dSPACE or xPC).
    MODELICA_EXPORT: Prefix used for function calls. If not defined, blank is used
                     Useful definitions:
                     - "static" that is all functions become static
                       (useful if file is included with other C-sources for an
                        embedded system)
                     - "__declspec(dllexport)" if included in a DLL and the
                       functions shall be visible outside of the DLL


    Release Notes:
      Nov. 20, 2014, by Thomas Beutlich, ITI GmbH.
        Fixed platform dependency of ModelicaInternal_readLine/_readFile (ticket #1580)

      May 21, 2013, by Martin Otter, DLR.
        Included the improvements from DS Lund:
          - Changed implementation of print to do nothing in case of missing file-system.
            Otherwise we just end up with an error message that is not written,
            and the failure in itself is not sufficiently fatal to just stop
          - Caching when reading from file

      March 26, 2013, by Martin Otter, DLR.
        Changed type of variable valueStart from int to size_t (ticket #1032)

      Jan.   5, 2013: by Martin Otter, DLR.
        Removed "static" declarations from the Modelica interface functions.

      Sept. 26, 2004: by Martin Otter, DLR.
        Added missing implementations, merged code from previous ModelicaFiles
        and clean-up of code.

      Sep.  9, 2004: by Dag Bruck, Dynasim AB.
        Further implementation and clean-up of code.

      Aug. 24, 2004: by Martin Otter, DLR.
        Adapted to Dymola 5.3 with minor improvements.

      Jan.  7, 2002: by Martin Otter, DLR.
        First version implemented.
        Only tested for _WIN32, but implemented all
        functions also for _POSIX_, with the exception of
        ModelicaInternal_getFullPath


    Copyright (C) 2002-2014, Modelica Association and DLR.


   The content of this file is free software; it can be redistributed
   and/or modified under the terms of the Modelica License 2, see the
   license conditions and the accompanying disclaimer in file
   Modelica/ModelicaLicense2.html or in Modelica.UsersGuide.ModelicaLicense2.

*/
#if !defined(MODELICA_EXPORT)
#   define MODELICA_EXPORT
#endif

#include <string.h>
#include "ModelicaUtilities.h"

static void ModelicaNotExistError(const char* name) {
   /* Print error message if a function is not implemented */
   ModelicaFormatError("C-Function \"%s\" is called\n"
                       "but is not implemented for the actual environment\n"
                       "(e.g., because there is no file system available on the machine\n"
                       "as for dSPACE or xPC systems)", name);
}

#ifdef NO_FILE_SYSTEM
  MODELICA_EXPORT void ModelicaInternal_mkdir(const char* directoryName) {
       ModelicaNotExistError("ModelicaInternal_mkdir"); }
  MODELICA_EXPORT void ModelicaInternal_rmdir(const char* directoryName) {
       ModelicaNotExistError("ModelicaInternal_rmdir"); }
  MODELICA_EXPORT int  ModelicaInternal_stat(const char* name) {
       ModelicaNotExistError("ModelicaInternal_stat"); return 0; }
  MODELICA_EXPORT void ModelicaInternal_rename(const char* oldName, const char* newName)  {
       ModelicaNotExistError("ModelicaInternal_rename"); }
  MODELICA_EXPORT void ModelicaInternal_removeFile(const char* file) {
       ModelicaNotExistError("ModelicaInternal_removeFile"); }
  MODELICA_EXPORT void ModelicaInternal_copyFile(const char* oldFile, const char* newFile) {
       ModelicaNotExistError("ModelicaInternal_copyFile"); }
  MODELICA_EXPORT void ModelicaInternal_readDirectory(const char* directory, int nFiles, const char* files[]) {
       ModelicaNotExistError("ModelicaInternal_readDirectory"); }
  MODELICA_EXPORT int  ModelicaInternal_getNumberOfFiles(const char* directory) {
       ModelicaNotExistError("ModelicaInternal_getNumberOfFiles"); return 0; }
  MODELICA_EXPORT const char* ModelicaInternal_fullPathName(const char* name) {
       ModelicaNotExistError("ModelicaInternal_fullPathName"); return 0; }
  MODELICA_EXPORT const char* ModelicaInternal_temporaryFileName(void) {
       ModelicaNotExistError("ModelicaInternal_temporaryFileName"); return 0; }
  MODELICA_EXPORT void ModelicaInternal_print(const char* string, const char* fileName) {
       if ( fileName[0] == '\0' ) {
           /* Write string to terminal */
           ModelicaFormatMessage("%s\n", string);
       }
       return; }
  MODELICA_EXPORT int  ModelicaInternal_countLines(const char* fileName) {
       ModelicaNotExistError("ModelicaInternal_countLines"); return 0; }
  MODELICA_EXPORT void ModelicaInternal_readFile(const char* fileName, const char* string[], size_t nLines) {
       ModelicaNotExistError("ModelicaInternal_readFile"); }
  MODELICA_EXPORT const char* ModelicaInternal_readLine(const char* fileName, int lineNumber, int* endOfFile) {
       ModelicaNotExistError("ModelicaInternal_readLine"); return 0; }
  MODELICA_EXPORT void ModelicaInternal_chdir(const char* directoryName) {
       ModelicaNotExistError("ModelicaInternal_chdir"); }
  MODELICA_EXPORT const char* ModelicaInternal_getcwd(int dummy) {
       ModelicaNotExistError("ModelicaInternal_getcwd"); return 0; }
  MODELICA_EXPORT void ModelicaInternal_getenv(const char* name, int convertToSlash, const char** content, int* exist) {
       ModelicaNotExistError("ModelicaInternal_getenv"); }
  MODELICA_EXPORT void ModelicaInternal_setenv(const char* name, const char* value, int convertFromSlash) {
       ModelicaNotExistError("ModelicaInternal_setenv"); }
#else

/* The standard way to detect if we have posix is to check _POSIX_VERSION,
 * which is defined in <unistd.h>
 */
#  if defined(__unix__) || defined(__linux__) || defined(__APPLE_CC__)
#    include <unistd.h>
#  endif

#  if !defined(_POSIX_) && defined(_POSIX_VERSION)
#    define _POSIX_ 1
#  endif

#  include <stdio.h>
#  include <stdlib.h>
#  include <errno.h>

#  if defined(__WATCOMC__)
#     include <direct.h>
#     include <sys/types.h>
#     include <sys/stat.h>
#  elif defined(__BORLANDC__)
#     include <direct.h>
#     include <sys/types.h>
#     include <sys/stat.h>
#     include <dirent.h>
#  elif defined(_WIN32)
#     include <direct.h>
#     include <sys/types.h>
#     include <sys/stat.h>

#     if defined(__MINGW32__) || defined(__CYGWIN__) /* MinGW and Cygwin have dirent.h */
#       include <dirent.h>
#     else /* include the opendir/readdir/closedir implementation for _WIN32 */
#       include "win32_dirent.c"
#     endif

#  elif defined(_POSIX_) || defined(__GNUC__)
#     include <dirent.h>
#     include <unistd.h>
#     include <sys/types.h>
#     include <sys/stat.h>
#  endif

#if PATH_MAX > 1024
#define BUFFER_LENGTH PATH_MAX
#else
#define BUFFER_LENGTH 1024
#endif
static char buffer[BUFFER_LENGTH];  /* Buffer for temporary storage. Should be sufficient for PATH_MAX on all standard platforms.  */

typedef enum {
   FileType_NoFile = 1,
   FileType_RegularFile,
   FileType_Directory,
   FileType_SpecialFile   /* pipe, FIFO, device, etc. */
} ModelicaFileType;



/* Convert to Unix directory separators: */
#if defined(_WIN32)
   static void ModelicaConvertToUnixDirectorySeparator(char* string) {
      /* convert to Unix directory separators */
      char* c = string;
      while ( *c ) {
         if ( *c == '\\' )  {*c = '/';}
         c++;
      }
   }

   static void ModelicaConvertFromUnixDirectorySeparator(char* string) {
      /* convert from Unix directory separators */
      char* c = string;
      while ( *c ) {
         if ( *c == '/' )  {*c = '\\';}
         c++;
      }
   }
#else
#  define ModelicaConvertToUnixDirectorySeparator(string) ;
#  define ModelicaConvertFromUnixDirectorySeparator(string) ;
#endif


/* --------------------- Modelica_Utilities.Internal --------------------------------- */

MODELICA_EXPORT void ModelicaInternal_mkdir(const char* directoryName)
{
    /* Create directory */

#if defined(__WATCOMC__)
    int result = mkdir(directoryName);
#elif defined(__BORLANDC__)
    int result = _mkdir(directoryName);
#elif defined(_WIN32)
    int result = _mkdir(directoryName);
#elif defined(_POSIX_) || defined(__GNUC__)
    int result = mkdir(directoryName, S_IRUSR | S_IWUSR | S_IXUSR);
#else
    int result = -1;
    ModelicaNotExistError("ModelicaInternal_mkdir");
#endif

    if (result != 0) {
        ModelicaFormatError("Not possible to create new directory\n"
            "\"%s\":\n%s", directoryName, strerror(errno));
    }
}


MODELICA_EXPORT void ModelicaInternal_rmdir(const char* directoryName)
{
#if defined(__WATCOMC__)
    int result = rmdir(directoryName);
#elif defined(__BORLANDC__)
    int result = _rmdir(directoryName);
#elif defined(_WIN32)
    int result = _rmdir(directoryName);
#elif defined(_POSIX_) || defined(__GNUC__)
    int result = rmdir(directoryName);
#else
    int result = -1;
    ModelicaNotExistError("ModelicaInternal_rmdir");
#endif

    if (result != 0) {
        ModelicaFormatError("Not possible to remove directory\n"
            "\"%s\":\n%s", directoryName, strerror(errno));
    }
}


MODELICA_EXPORT int ModelicaInternal_stat(const char* name)
{
    /* Inquire type of file */
    ModelicaFileType type = FileType_NoFile;

#if defined(__WATCOMC__) || defined(__BORLANDC__)
     struct _stat fileInfo;
     if ( _stat(name, &fileInfo) != 0 ) {
         type = FileType_NoFile;
     } else if ( fileInfo.st_mode & S_IFREG ) {
         type = FileType_RegularFile;
     } else if ( fileInfo.st_mode & S_IFDIR ) {
         type = FileType_Directory;
     } else {
         type = FileType_SpecialFile;
     }
#elif defined(_WIN32)
     struct _stat fileInfo;
     int statReturn;
     statReturn=_stat(name, &fileInfo);
     if (statReturn!=0) {
        /* For some reason _stat requires a:\ and a:\test1 and fails on a: and a:\test1\ */
        /* It could be handled in the Modelica code, but seems better to have here */
        if (strpbrk(name,"/\\")==0 && strchr(name,':')!=0 && strchr(name,':')[1]==0 && (strchr(name,':')-name)<40) {
           char name2[100];
           strcpy(name2,name);
           strcat(name2,"\\");
           statReturn=_stat(name2, &fileInfo);
        }
    }
    if ( statReturn != 0 ) {
        type = FileType_NoFile;
    } else if ( fileInfo.st_mode & S_IFREG ) {
        type = FileType_RegularFile;
    } else if ( fileInfo.st_mode & S_IFDIR ) {
        type = FileType_Directory;
    } else {
        type = FileType_SpecialFile;
    }
#elif defined(_POSIX_) || defined(__GNUC__)
    struct stat fileInfo;
    int statReturn;
    statReturn=stat(name, &fileInfo);
    if ( statReturn != 0 ) {
        type = FileType_NoFile;
    } else if ( S_ISREG(fileInfo.st_mode) ) {
        type = FileType_RegularFile;
    } else if ( S_ISDIR(fileInfo.st_mode) ) {
        type = FileType_Directory;
    } else {
        type = FileType_SpecialFile;
    }
#else
    ModelicaNotExistError("ModelicaInternal_stat");
#endif
    return type;
}


MODELICA_EXPORT void ModelicaInternal_rename(const char* oldName, const char* newName) {
   /* Changes the name of a file or of a directory */

   if ( rename(oldName, newName) != 0 ) {
      ModelicaFormatError("renaming \"%s\" to \"%s\" failed:\n%s",
                    oldName, newName, strerror(errno));
   }
}


MODELICA_EXPORT void ModelicaInternal_removeFile(const char* file) {
  /* Remove file. */
  if ( remove(file) != 0 ) {
     ModelicaFormatError("Not possible to remove file \"%s\":\n%s",
                   file, strerror(errno));
  }
}


MODELICA_EXPORT void ModelicaInternal_copyFile(const char* oldFile, const char* newFile) {
  /* Copy file */
     #ifdef _WIN32
        const char* modeOld = "rb";
        const char* modeNew = "wb";
     #else
        const char* modeOld = "r";
        const char* modeNew = "w";
     #endif
     FILE* fpOld;
     FILE* fpNew;
     ModelicaFileType type;
     int c;

  /* Check file existence */
     type = (ModelicaFileType) ModelicaInternal_stat(oldFile);
     if ( type == FileType_NoFile ) {
        ModelicaFormatError("\"%s\" cannot be copied\nbecause it does not exist", oldFile);
        return;
     } else if ( type == FileType_Directory ) {
        ModelicaFormatError("\"%s\" cannot be copied\nbecause it is a directory", oldFile);
        return;
     } else if ( type == FileType_SpecialFile ) {
        ModelicaFormatError("\"%s\" cannot be copied\n"
                      "because it is not a regular file", oldFile);
        return;
     }
     type = (ModelicaFileType) ModelicaInternal_stat(newFile);
     if ( type != FileType_NoFile ) {
        ModelicaFormatError("\"%s\" cannot be copied\nbecause the target "
                      "\"%s\" exists", oldFile, newFile);
        return;
     }

  /* Copy file */
     fpOld = fopen(oldFile, modeOld);
     if ( fpOld == NULL ) {
        ModelicaFormatError("\"%s\" cannot be copied:\n%s", oldFile, strerror(errno));
        return;
     }
     fpNew = fopen(newFile, modeNew);
     if ( fpNew == NULL ) {
        fclose(fpOld);
        ModelicaFormatError("\"%s\" cannot be copied to \"%s\":\n%s",
                      oldFile, newFile, strerror(errno));
        return;
     }
     while ( (c = getc(fpOld)) != EOF ) putc(c, fpNew);
     fclose(fpOld);
     fclose(fpNew);
}


MODELICA_EXPORT void ModelicaInternal_readDirectory(const char* directory, int nFiles,
                                           const char** files) {
  /* Get all file and directory names in a directory in any order
     (must be very careful, to call closedir if an error occurs)
  */
  #if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_WIN32) || defined(_POSIX_) || defined(__GNUC__)
     int errnoTemp;
     int iFiles  = 0;
     char *pName;
     struct dirent *pinfo;
     DIR* pdir;

     /* Open directory information inquiry */
        pdir = opendir(directory);
        if ( pdir == NULL ) {
           ModelicaFormatError("1: Not possible to get file names of \"%s\":\n%s",
                         directory, strerror(errno));
        }

     /* Read file and directory names and store them in vector "files" */
     errno = 0;
     while ( (pinfo = readdir(pdir)) != NULL ) {
        if ( (strcmp(pinfo->d_name, "." ) != 0) &&
             (strcmp(pinfo->d_name, "..") != 0) ) {
           /* Check if enough space in "files" vector */
              if ( iFiles >= nFiles ) {
                closedir(pdir);
                ModelicaFormatError("Not possible to get file names of \"%s\":\n"
                              "More files in this directory as reported by nFiles (= %i)",
                              directory, nFiles);
              }

           /* Allocate Modelica memory for file/directory name and copy name */
              pName = ModelicaAllocateStringWithErrorReturn(strlen(pinfo->d_name));
              if ( pName == NULL ) {
                errnoTemp = errno;
                closedir(pdir);
                if ( errnoTemp == 0 ) {
                   ModelicaFormatError("Not possible to get file names of \"%s\":\n"
                                 "Not enough storage", directory);
                } else {
                   ModelicaFormatError("Not possible to get file names of \"%s\":\n%s",
                                 directory, strerror(errnoTemp));
                }
              }
              strcpy(pName, pinfo->d_name);

           /* Save pointer to file */
              files[iFiles] = pName;
              iFiles++;
        }
     }

     if ( errno != 0 ) {
        errnoTemp = errno;
        closedir(pdir);
        ModelicaFormatError("Not possible to get file names of \"%s\":\n%s",
                      directory, strerror(errnoTemp));
     }


     /* Check, whether the whole "files" vector is filled and close inquiry */
        if ( iFiles != nFiles) {
           closedir(pdir);
           ModelicaFormatError("Not possible to get file names of \"%s\":\n"
                         "Less files (= %d) found as defined by argument nNames (= %d)",
                         directory, iFiles, nFiles);
        }

        if ( closedir(pdir) != 0 ) {
           ModelicaFormatError("Not possible to get file names of \"%s\":\n",
                         directory, strerror(errno));
        }

  #else
     ModelicaNotExistError("ModelicaInternal_readDirectory");
  #endif
}


MODELICA_EXPORT int ModelicaInternal_getNumberOfFiles(const char* directory) {
    /* Get number of files and directories in a directory */

#if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_WIN32) || defined(_POSIX_) || defined(__GNUC__)
    int nFiles = 0;
    int errnoTemp;
    struct dirent *pinfo;
    DIR* pdir;

    pdir = opendir(directory);
    if ( pdir == NULL ) goto Modelica_ERROR;
    errno = 0;
    while ( (pinfo = readdir(pdir)) != NULL ) {
        if ( (strcmp(pinfo->d_name, "." ) != 0) &&
            (strcmp(pinfo->d_name, "..") != 0) ) {
            nFiles++;
        }
    }
    errnoTemp = errno;
    closedir(pdir);
    if ( errnoTemp != 0 ) {errno = errnoTemp; goto Modelica_ERROR;}

    return nFiles;

Modelica_ERROR: ModelicaFormatError("Not possible to get number of files in \"%s\":\n%s",
                                    directory, strerror(errno));
       return 0;
#else
       ModelicaNotExistError("ModelicaInternal_getNumberOfFiles");
       return 0;
#endif
}


/* --------------------- Modelica_Utilities.Files ------------------------------------- */

MODELICA_EXPORT const char* ModelicaInternal_fullPathName(const char* name)
{
    /* Get full path name of file or directory */

    char* fullName=0;

#if defined(_WIN32) || (_BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED || (_POSIX_VERSION >= 200112L))
#if (_BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED || _POSIX_VERSION >= 200112L)
    /* realpath availability: 4.4BSD, POSIX.1-2001. Using the behaviour of NULL: POSIX.1-2008 */
    char* tempName = realpath(name, buffer);
#else
    char* tempName = _fullpath(buffer, name, sizeof(buffer));
#endif
    if (tempName == NULL) {
        ModelicaFormatError("Not possible to construct full path name of \"%s\"\n%s",
            name, strerror(errno));
        return "";
    }
    fullName = ModelicaAllocateString(strlen(tempName));
    strcpy(fullName, tempName);
    ModelicaConvertToUnixDirectorySeparator(fullName);
#elif defined(_POSIX_)
    /* No such system call in _POSIX_ available (except realpath above) */
    char* cwd = getcwd(buffer, sizeof(buffer));
    if (cwd == NULL) {
        ModelicaFormatError("Not possible to get current working directory:\n%s",
            strerror(errno));
    }
    fullName = ModelicaAllocateString(strlen(cwd) + strlen(name) + 1);
    if (name[0] != '/') {
        /* Any name beginning with "/" is regarded as already being a full path. */
        strcpy(fullName, cwd);
        strcat(fullName, "/");
    }
    strcat(fullName, name);
#else
    ModelicaNotExistError("ModelicaInternal_fullPathName");
#endif

    return fullName;
}

MODELICA_EXPORT const char* ModelicaInternal_temporaryFileName(void)
{
    /* Get full path name of a temporary */

    char* fullName;

    char* tempName = tmpnam(NULL);
    if (tempName == NULL) {
        ModelicaFormatError("Not possible to get temporary filename\n%s", strerror(errno));
        return "";
    }
    fullName = ModelicaAllocateString(strlen(tempName));
    strcpy(fullName, tempName);
    ModelicaConvertToUnixDirectorySeparator(fullName);

    return fullName;
}



/* --------------------- Abstract data type for stream handles --------------------- */

/* Improved for caching of the open files */
static char cached_fileName[300];
static FILE*cached_fp=0;
static int cached_line;

static void CacheFileForReading(FILE*f,const char*fileName, int line) {
    if (cached_fp!=0) {
        FILE*f1=cached_fp;
        cached_fp=0;
        fclose(f1);
    }
    if (fileName==0 || strlen(fileName)+1>=sizeof(cached_fileName)) {
        /* Do not add, close file */
        if (f)
            fclose(f);
        return;
    }
    strcpy(cached_fileName, fileName);
    cached_fp=f;
    cached_line=line;
}
static void CloseCachedFile() {
    CacheFileForReading(0,0,0);
}

static FILE* ModelicaStreams_openFileForReading(const char* fileName, int line) {
   /* Open text file for reading */
      FILE* fp;
      int c;

   /* Open file */
      if (cached_fp && line!=0 && line>=cached_line && strncmp(fileName, cached_fileName, sizeof(cached_fileName))==0) {
          /* Cached value */
          line-=cached_line;
          fp=cached_fp;
          cached_fp=0;
      } else {
        fp = fopen(fileName, "r");
        if ( fp == NULL ) {
            ModelicaFormatError("Not possible to open file \"%s\" for reading:\n"
                "%s\n", fileName, strerror(errno));
        }
      }
      c = 1;
      while ( line!=0 && c!=EOF) {
          c = fgetc(fp);
          while ( c != '\n' && c != EOF ) {
              c = fgetc(fp);
          }
          line--;
      }
      return fp;
}

MODELICA_EXPORT void ModelicaStreams_closeFile(const char* fileName) {
   /* close file */
    if (cached_fp && strncmp(fileName, cached_fileName, sizeof(cached_fileName))==0) {
        CloseCachedFile(); /* Closes it */
    }
}


static FILE* ModelicaStreams_openFileForWriting(const char* fileName) {
   /* Open text file for writing (with append) */
      FILE* fp;

   /* Check fileName */
      if ( strlen(fileName) == 0 ) {
         ModelicaError("fileName is an empty string.\n"
                       "Opening of file is aborted\n");
      }

   /* Open file */
      ModelicaStreams_closeFile(fileName);
      fp = fopen(fileName, "a");
      if ( fp == NULL ) {
         ModelicaFormatError("Not possible to open file \"%s\" for writing:\n"
                             "%s\n", fileName, strerror(errno));
      }
      return fp;
}


/* --------------------- Modelica_Utilities.Streams ----------------------------------- */

MODELICA_EXPORT void ModelicaInternal_print(const char* string, const char* fileName) {
  /* Write string to terminal or to file */

     if ( fileName[0] == '\0' ) {
        /* Write string to terminal */
           ModelicaFormatMessage("%s\n", string);
     } else {
        /* Write string to file */
           FILE* fp = ModelicaStreams_openFileForWriting(fileName);
           if ( fputs(string,fp) < 0 ) goto Modelica_ERROR2;
           if ( fputs("\n",fp)   < 0 ) goto Modelica_ERROR2;
           fclose(fp);
           return;

           Modelica_ERROR2: fclose(fp);
                            ModelicaFormatError("Error when writing string to file \"%s\":\n"
                                                "%s\n", fileName, strerror(errno));
     }
}


MODELICA_EXPORT int ModelicaInternal_countLines(const char* fileName)
/* Get number of lines of a file */
{
    int c;
    int nLines = 0;
    int start_of_line = 1;
    /* If true, next character starts a new line. */

    FILE* fp = ModelicaStreams_openFileForReading(fileName, 0);

    /* Count number of lines */
    while ((c = fgetc(fp)) != EOF) {
        if (start_of_line) {
            nLines++;
            start_of_line = 0;
        }
        if (c == '\n') start_of_line = 1;
    }
    fclose(fp);
    return nLines;
}

MODELICA_EXPORT void ModelicaInternal_readFile(const char* fileName, const char* string[], size_t nLines) {
  /* Read file into string vector string[nLines] */
     FILE* fp = ModelicaStreams_openFileForReading(fileName, 0);
     char*  line;
     int    c, c2;
     size_t lineLen;
     size_t iLines;
     long   offset;
     size_t nc;
     char localbuf[200]; /* To avoid fseek */

  /* Read data from file */
     iLines = 1;
     while ( iLines <= nLines ) {
        /* Determine length of next line */
           offset  = ftell(fp);
           lineLen = 0;
           c = fgetc(fp);
           c2 = c;
           while ( c != '\n' && c != EOF ) {
              if (lineLen < sizeof(localbuf)) localbuf[lineLen]=c;
              lineLen++;
              c2 = c;
              c = fgetc(fp);
           }

           if ( lineLen > 0 && c2 == '\r' ) {
              lineLen--;
           }
        /* Allocate storage for next line */
           line = ModelicaAllocateStringWithErrorReturn(lineLen);
           if ( line == NULL ) {
              fclose(fp);
              ModelicaFormatError("Not enough memory to allocate string for reading line %i from file\n"
                                  "\"%s\".\n"
                                  "(this file contains %i lines)\n", iLines, fileName, nLines);
           }

        /* Read next line */
              if (lineLen<=sizeof(localbuf)) {
                 memcpy(line, localbuf, lineLen);
              } else {
              if ( fseek(fp, offset, SEEK_SET != 0) ) {
                 fclose(fp);
                 ModelicaFormatError("Error when reading line %i from file\n\"%s\":\n"
                                     "%s\n", iLines, fileName, strerror(errno));
              }
              nc = ( iLines < nLines ? lineLen+1 : lineLen);
              if ( fread(line, sizeof(char), nc, fp) != nc ) {
                 fclose(fp);
                 ModelicaFormatError("Error when reading line %i from file\n\"%s\"\n",
                                     iLines, fileName);
              }
           }
           line[lineLen] = '\0';
           string[iLines-1] = line;
           iLines++;
     }
     fclose(fp);
}


MODELICA_EXPORT const char* ModelicaInternal_readLine(const char* fileName, int lineNumber, int* endOfFile) {
  /* Read line lineNumber from file fileName */
     FILE*  fp = ModelicaStreams_openFileForReading(fileName, lineNumber-1);
     char*  line;
     int    c, c2;
     size_t lineLen;
     long   offset;
     char   localbuf[200]; /* To avoid fseek */

  if (feof(fp)) goto END_OF_FILE;

  /* Determine length of line lineNumber */
     offset  = ftell(fp);
     lineLen = 0;
     c = fgetc(fp);
     c2 = c;
     while ( c != '\n' && c != EOF ) {
        if (lineLen<sizeof(localbuf)) localbuf[lineLen]=c;
        lineLen++;
        c2 = c;
        c = fgetc(fp);
     }
     if ( lineLen == 0 && c == EOF ) goto END_OF_FILE;

  /* Read line lineNumber */
     if ( lineLen > 0 && c2 == '\r' ) {
        lineLen--;
     }
     line = ModelicaAllocateStringWithErrorReturn(lineLen);
     if ( line == NULL ) goto Modelica_ERROR3;

     if (lineLen <= sizeof(localbuf)) {
        memcpy(line, localbuf, lineLen);
     } else {
        if ( fseek(fp, offset, SEEK_SET) != 0 ) goto Modelica_ERROR3;
        if ( fread(line, sizeof(char), lineLen, fp) != lineLen ) goto Modelica_ERROR3;
        fgetc(fp); /* Read the EOF/new-line. */
     }
     CacheFileForReading(fp, fileName, lineNumber);
     line[lineLen] = '\0';
     *endOfFile = 0;
     return line;

  /* End-of-File or error */
     END_OF_FILE: fclose(fp);
                  *endOfFile = 1;
                  line = ModelicaAllocateString(0);
                  return line;

     Modelica_ERROR3: fclose(fp);
                      ModelicaFormatError("Error when reading line %i from file\n\"%s\":\n%s",
                                          lineNumber, fileName, strerror(errno));
                      return "";
}


/* --------------------- Modelica_Utilities.System ------------------------------------ */

MODELICA_EXPORT void ModelicaInternal_chdir(const char* directoryName)
{
/* Change current working directory. */
#if defined(__WATCOMC__)
    int result = chdir(directoryName);
#elif defined(__BORLANDC__)
    int result = chdir(directoryName);
#elif defined(_WIN32)
    int result = _chdir(directoryName);
#elif defined(_POSIX_) || defined(__GNUC__)
    int result = chdir(directoryName);
#else
    int result = -1;
    ModelicaNotExistError("ModelicaInternal_chdir");
#endif

    if (result != 0) {
        ModelicaFormatError("Not possible to change current working directory to\n"
            "\"%s\":\n%s", directoryName, strerror(errno));
    }
}


MODELICA_EXPORT const char* ModelicaInternal_getcwd(int dummy)
{
    const char* cwd;
    char* directory;

#if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_POSIX_) || defined(__GNUC__)
    cwd = getcwd(buffer, sizeof(buffer));
#elif defined(_WIN32)
    cwd = _getcwd(buffer, sizeof(buffer));
#else
    ModelicaNotExistError("ModelicaInternal_getcwd");
    cwd = "";
#endif

    if (cwd == NULL) {
        ModelicaFormatError("Not possible to get current working directory:\n%s",
            strerror(errno));
        cwd = "";
    }

    directory = ModelicaAllocateString(strlen(cwd));
    strcpy(directory, cwd);
    ModelicaConvertToUnixDirectorySeparator(directory);
    return directory;
}


MODELICA_EXPORT void ModelicaInternal_getenv(const char* name, int convertToSlash, const char** content, int* exist)
{
    /* Get content of environment variable */
    char* value = getenv(name);
    char* result;

    if (value == NULL) {
        result = ModelicaAllocateString(0);
        result[0] = '\0';
        *exist = 0;
    } else {
        result = ModelicaAllocateString(strlen(value));
        strcpy(result, value);
        if ( convertToSlash == 1 ) ModelicaConvertToUnixDirectorySeparator(result);
        *exist = 1;
    }
    *content = result;
}


MODELICA_EXPORT void ModelicaInternal_setenv(const char* name, const char* value, int convertFromSlash)
{
#if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_WIN32) || defined(_POSIX_) || defined(__GNUC__)

    size_t valueStart;
    if (strlen(name) + strlen(value) + 1 > sizeof(buffer)) {
        ModelicaFormatError("Environment variable\n"
            "\"%s\"=\"%s\"\n"
            "cannot be set, because the internal buffer\n"
            "in file \"ModelicaInternal.c\" is too small (= %d)",
            name, value, sizeof(buffer));
    }

    strcpy(buffer,name);
    strcat(buffer, "=");
    valueStart = strlen(buffer);
    strcat(buffer, value);

    if ( convertFromSlash == 1 ) ModelicaConvertFromUnixDirectorySeparator(&buffer[valueStart]);
#endif

    /* Set environment variable */
#if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_POSIX_) || defined(__GNUC__)
    if (putenv(buffer) != 0) {
        ModelicaFormatError("Environment variable\n"
            "\"%s\"=\"%s\"\n"
            "cannot be set: %s", name, value, strerror(errno));
    }

#elif defined(_WIN32)
    if (_putenv(buffer) != 0) {
        ModelicaFormatError("Environment variable\n"
            "\"%s\"=\"%s\"\n"
            "cannot be set: %s", name, value, strerror(errno));
    }
#else
    ModelicaNotExistError("ModelicaInternal_setenv");
#endif
}

#endif
