X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=src%2Ftexsourc%2Fopeninou.c;h=a8a222742430c3d3c23dc5eb091c67f5cac5f2a6;hb=ae80400414b6d1c308c3e3036a267ca50549c016;hp=80db4147d64bdd7950e54a01fc6415201b7f3241;hpb=065ab3b4065a0065b5013107cd3a24e8b6cbfa57;p=putex%2Fputex.git

diff --git a/src/texsourc/openinou.c b/src/texsourc/openinou.c
index 80db414..a8a2227 100644
--- a/src/texsourc/openinou.c
+++ b/src/texsourc/openinou.c
@@ -1,398 +1,398 @@
-/* Copyright 1992 Karl Berry
-   Copyright 2007 TeX Users Group
-   Copyright 2014 Clerk Ma
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301 USA.  */
-
-#define EXTERN extern
-
-#include "yandytex.h"
-#undef name
-
-#define PATH_SEP        '/'
-#define PATH_SEP_STRING "/"
-
-#define BUILDNAMEDIRECT
-
-extern int shorten_file_name;
-
-#ifdef FUNNY_CORE_DUMP
-  extern void funny_core_dump(void);
-#endif
-
-#ifdef BUILDNAMEDIRECT
-char * xconcat (char * buffer, char * s1, char * s2)
-{
-  int n1 = strlen(s1);
-  int n2 = strlen(s2);
-
-  if (buffer == s2)
-  {
-    memmove(buffer + n1, buffer, n2 + 1);
-    strncpy(buffer, s1, n1);
-  }
-  else
-  {
-    strcpy(buffer, s1);
-    strcat(buffer + n1, s2);
-  }
-
-  return buffer;
-}
-char * xconcat3 (char *buffer, char *s1, char *s2, char *s3)
-{
-  int n1 = strlen(s1);
-  int n2 = strlen(s2);
-  int n3 = strlen(s3);
-
-  if (buffer == s3)
-  {
-    memmove(buffer + n1 + n2, buffer, n3 + 1);
-    strncpy(buffer, s1, n1);
-    strncpy(buffer + n1, s2, n2);
-  }
-  else
-  {
-    strcpy(buffer, s1);
-    strcat(buffer + n1, s2);
-    strcat(buffer + n1 + n2, s3);
-  }
-
-  return buffer;
-}
-#endif
-
-void patch_in_path (ASCII_code * buffer, ASCII_code *name, ASCII_code * path)
-{
-  if (*path == '\0')
-    strcpy((char *) buffer, (char *) name);
-  else
-    xconcat3((char *) buffer, (char *) path, "/", (char *) name);
-}
-
-int qualified (ASCII_code * name)
-{
-  if (strchr((char *) name, '/') != NULL ||
-      strchr((char *) name, '\\') != NULL ||
-      strchr((char *) name, ':') != NULL)
-    return 1;
-  else
-    return 0;
-}
-/* patch path if 
-    (i)   path not empty
-    (ii)  name not qualified
-    (iii) ext match
-*/
-int prepend_path_if(ASCII_code * buffer, ASCII_code * name, const char * ext, char *path)
-{
-  if (path == NULL)
-    return 0;
-
-  if (*path == '\0')
-    return 0;
-
-  if (qualified(name))
-    return 0;
-
-  if (strstr((char *) name, ext) == NULL)
-    return 0;
-
-  patch_in_path(buffer, name, (ASCII_code *)path);
-
-  return 1;
-}
-
-//  Following works on null-terminated strings
-void check_short_name (unsigned char *s)
-{
-  unsigned char *star, *sdot;
-  int n;
-
-  if ((star = (unsigned char *) strrchr((char *) s, '\\')) != NULL)
-    star++;
-  else if ((star = (unsigned char *) strrchr((char *) s, '/')) != NULL)
-    star++;
-  else if ((star = (unsigned char *) strchr((char *) s, ':')) != NULL)
-    star++;
-  else
-    star = s;
-
-  if ((sdot = (unsigned char *) strchr((char *) star, '.')) != NULL)
-    n = sdot - star;
-  else
-    n = strlen((char *) star);
-
-  if (n > 8)
-    strcpy((char *) star + 8, (char *) star + n);
-
-  if ((sdot = (unsigned char *) strchr((char *) star, '.')) != NULL)
-  {
-    star = sdot + 1;
-
-    n = strlen((char *) star);
-
-    if (n > 3)
-      *(star + 3) = '\0';
-  }
-}
-
-/* Following works on both null-terminated names */
-
-void retwiddle (unsigned char *s)
-{
-  while (*s != '\0')
-  {
-    if (*s == (unsigned char) pseudo_tilde)
-      *s = '~';
-    else if (*s == (unsigned char) pseudo_space)
-      *s = ' ';
-
-    s++;
-  }
-}
-
-boolean open_input (FILE ** f, kpse_file_format_type file_fmt, const char * fopen_mode)
-{
-  boolean openable = false;
-  char * file_name = NULL;
-
-#if defined (FUNNY_CORE_DUMP) && !defined (BibTeX)
-  if (file_fmt == kpse_tex_format &&
-    strncmp(name_of_file + 1, "HackyInputFileNameForCoreDump.tex", 33) == 0)
-    funny_core_dump();
-#endif
-
-  if (return_flag)
-  {
-    if (strcmp(fopen_mode, "r") == 0)
-      fopen_mode = "rb";
-  }
-
-  name_of_file[name_length + 1] = '\0';
-
-  /* reinsert '~' and ' ' in file names */  
-  if (pseudo_tilde != 0 || pseudo_space != 0)
-    retwiddle(name_of_file + 1);
-
-  if (shorten_file_name)
-    check_short_name(name_of_file + 1);
-  
-  if (open_trace_flag)
-    printf(" Open `%s' for input ", name_of_file + 1);
-
-  file_name = kpse_find_file((const_string) name_of_file + 1, file_fmt, false);
-
-  if (file_name != NULL)
-  {
-    strcpy ((char *) name_of_file + 1, file_name);
-    *f = xfopen((char *) file_name, fopen_mode);
-
-#ifdef _WIN32
-    if (name_of_file[1] == '.' && (name_of_file[2] == PATH_SEP || name_of_file[2] == '\\'))
-#else
-    if (name_of_file[1] == '.' && name_of_file[2] == PATH_SEP)
-#endif
-    {
-      unsigned i = 1;
-
-      while (name_of_file[i + 2] != '\0')
-      {
-        name_of_file[i] = name_of_file[i + 2];
-        i++;
-      }
-
-      name_of_file[i] = '\0';
-      name_length = i - 1;
-    }
-    else
-      name_length = strlen((char *) name_of_file + 1);
-      
-    if (file_fmt == kpse_tfm_format)
-    {
-      fbyte = getc(*f);
-    } 
-
-    if (strstr((char *) name_of_file + 1, ".fmt") != NULL)
-    {
-      if (format_file == NULL)
-        format_file = xstrdup((char *) name_of_file + 1);
-
-#ifdef COMPACTFORMAT
-      gz_fmt_file = gzdopen(fileno(*f), "rb9");
-#endif
-    }
-    else if (strstr((char *) name_of_file + 1, ".tfm") != NULL)
-    {
-      if (show_tfm_flag && log_opened)
-      {
-        int n; 
-        n = strlen((char *) name_of_file + 1);
-
-        if (file_offset + n > max_print_line)
-        {
-          (void) putc('\n', log_file);
-          file_offset = 0;
-        }
-        else
-          (void) putc(' ', log_file);
-
-        fprintf(log_file, "(%s)", name_of_file + 1);
-        file_offset += n + 3;
-      }
-    }
-    else if (source_direct == NULL)
-    {
-      char *s;
-
-      source_direct = xstrdup((char *) name_of_file + 1);
-
-      if (trace_flag)
-        printf("Methinks the source %s is `%s'\n", "file", source_direct);
-
-      if ((s = strrchr(source_direct, '/')) == NULL)
-        *source_direct = '\0';
-      else
-        *(s + 1) = '\0';
-
-      if (trace_flag)
-        printf("Methinks the source %s is `%s'\n", "directory", source_direct);
-    }
-
-    openable = true;
-  }
-
-  {
-    unsigned temp_length = strlen((char *) name_of_file + 1);
-    name_of_file[temp_length + 1] = ' ';
-  }
-
-  return openable;
-}
-
-/* At least check for I/O error (such as disk full) when closing */
-/* Would be better to check while writing - but this is better than nothing */
-/* This is used for both input and output files, but never mind ... */
-
-/* now a_close returns -1 on error --- which could be used by caller */
-/* probably want to ignore on input files ... */
-
-// check_fclose not used by anything
-int check_fclose (FILE * f)
-{
-  if (f == NULL)
-    return 0;
-
-  if (ferror(f) || fclose (f))
-  {
-    perrormod("\n! I/O Error");
-    uexit(EXIT_FAILURE);
-  }
-
-  return 0;
-}
-
-char * xstrdup_name (void)
-{
-  if (qualified(name_of_file + 1))
-    *log_line = '\0';
-  else
-  {
-    (void) getcwd(log_line, sizeof(log_line));
-    strcat(log_line, PATH_SEP_STRING);
-  }
-
-  strcat(log_line, (char *) name_of_file + 1);
-  unixify(log_line);
-  return xstrdup(log_line);
-}
-
-boolean open_output (FILE ** f, const char * fopen_mode)
-{
-  unsigned temp_length;
-
-  name_of_file[name_length + 1] = '\0';
-
-  if (pseudo_tilde != 0 || pseudo_space !=  0)
-    retwiddle(name_of_file + 1);
-
-  /* 8 + 3 file names on Windows NT 95/Feb/20 */
-  if (shorten_file_name)
-    check_short_name(name_of_file + 1);
-
-  if (prepend_path_if(name_of_file + 1, name_of_file + 1, ".dvi", dvi_directory) ||
-      prepend_path_if(name_of_file + 1, name_of_file + 1, ".log", log_directory) ||
-      prepend_path_if(name_of_file + 1, name_of_file + 1, ".aux", aux_directory) ||
-      prepend_path_if(name_of_file + 1, name_of_file + 1, ".fmt", fmt_directory) ||
-      prepend_path_if(name_of_file + 1, name_of_file + 1, ".pdf", pdf_directory))
-  {
-    if (open_trace_flag)
-      printf("After prepend %s\n", name_of_file + 1);
-  }
-
-  if (open_trace_flag)
-    printf(" Open `%s' for output ", name_of_file + 1);
-
-  *f = fopen((char *) name_of_file + 1, fopen_mode);
-
-  if (*f == NULL)
-  {
-    string temp_dir = kpse_var_value("TEXMFOUTPUT");
-
-    if (temp_dir != NULL)
-    {
-#ifdef BUILDNAMEDIRECT
-      unsigned char temp_name[file_name_size];
-      xconcat3((char *) temp_name, temp_dir, PATH_SEP_STRING, (char *) name_of_file + 1);
-#else
-      string temp_name = concat3(temp_dir, PATH_SEP_STRING, name_of_file + 1);
-#endif
-
-      if (deslash)
-        unixify((char *) temp_name);
-      
-      /* but we can assume this is opening here for *output* */
-      *f = fopen((char *) temp_name, fopen_mode);
-      /* If this succeeded, change name_of_file accordingly. */
-      if (*f)
-        strcpy((char *) name_of_file + 1, (char *) temp_name);
-
-#ifndef BUILDNAMEDIRECT
-      free (temp_name);
-#endif
-    }
-  }
-
-#ifdef COMPACTFORMAT
-  if (strstr((char *) name_of_file + 1, ".fmt") != NULL)
-    gz_fmt_file = gzdopen(fileno(*f), "wb9");
-#endif
-
-  if (strstr((char *) name_of_file + 1, ".dvi") != NULL)
-    dvi_file_name = xstrdup_name();
-  else if (strstr((char *) name_of_file + 1, ".pdf") != NULL)
-    pdf_file_name = xstrdup_name();
-  else if (strstr((char *) name_of_file + 1, ".log") != NULL)
-    log_file_name = xstrdup_name();
-
-  temp_length = strlen((char *) name_of_file + 1);
-  name_of_file[temp_length + 1] = ' ';
-
-  if (*f)
-    name_length = temp_length;
-  
-  return (*f != NULL);
+/* Copyright 1992 Karl Berry
+   Copyright 2007 TeX Users Group
+   Copyright 2014 Clerk Ma
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301 USA.  */
+
+#define EXTERN extern
+
+#include "yandytex.h"
+#undef name
+
+#define PATH_SEP        '/'
+#define PATH_SEP_STRING "/"
+
+#define BUILDNAMEDIRECT
+
+extern int shorten_file_name;
+
+#ifdef FUNNY_CORE_DUMP
+  extern void funny_core_dump(void);
+#endif
+
+#ifdef BUILDNAMEDIRECT
+char * xconcat (char * buffer, char * s1, char * s2)
+{
+  int n1 = strlen(s1);
+  int n2 = strlen(s2);
+
+  if (buffer == s2)
+  {
+    memmove(buffer + n1, buffer, n2 + 1);
+    strncpy(buffer, s1, n1);
+  }
+  else
+  {
+    strcpy(buffer, s1);
+    strcat(buffer + n1, s2);
+  }
+
+  return buffer;
+}
+char * xconcat3 (char *buffer, char *s1, char *s2, char *s3)
+{
+  int n1 = strlen(s1);
+  int n2 = strlen(s2);
+  int n3 = strlen(s3);
+
+  if (buffer == s3)
+  {
+    memmove(buffer + n1 + n2, buffer, n3 + 1);
+    strncpy(buffer, s1, n1);
+    strncpy(buffer + n1, s2, n2);
+  }
+  else
+  {
+    strcpy(buffer, s1);
+    strcat(buffer + n1, s2);
+    strcat(buffer + n1 + n2, s3);
+  }
+
+  return buffer;
+}
+#endif
+
+void patch_in_path (ASCII_code * buffer, ASCII_code *name, ASCII_code * path)
+{
+  if (*path == '\0')
+    strcpy((char *) buffer, (char *) name);
+  else
+    xconcat3((char *) buffer, (char *) path, "/", (char *) name);
+}
+
+int qualified (ASCII_code * name)
+{
+  if (strchr((char *) name, '/') != NULL ||
+      strchr((char *) name, '\\') != NULL ||
+      strchr((char *) name, ':') != NULL)
+    return 1;
+  else
+    return 0;
+}
+/* patch path if 
+    (i)   path not empty
+    (ii)  name not qualified
+    (iii) ext match
+*/
+int prepend_path_if(ASCII_code * buffer, ASCII_code * name, const char * ext, char *path)
+{
+  if (path == NULL)
+    return 0;
+
+  if (*path == '\0')
+    return 0;
+
+  if (qualified(name))
+    return 0;
+
+  if (strstr((char *) name, ext) == NULL)
+    return 0;
+
+  patch_in_path(buffer, name, (ASCII_code *)path);
+
+  return 1;
+}
+
+//  Following works on null-terminated strings
+void check_short_name (unsigned char *s)
+{
+  unsigned char *star, *sdot;
+  int n;
+
+  if ((star = (unsigned char *) strrchr((char *) s, '\\')) != NULL)
+    star++;
+  else if ((star = (unsigned char *) strrchr((char *) s, '/')) != NULL)
+    star++;
+  else if ((star = (unsigned char *) strchr((char *) s, ':')) != NULL)
+    star++;
+  else
+    star = s;
+
+  if ((sdot = (unsigned char *) strchr((char *) star, '.')) != NULL)
+    n = sdot - star;
+  else
+    n = strlen((char *) star);
+
+  if (n > 8)
+    strcpy((char *) star + 8, (char *) star + n);
+
+  if ((sdot = (unsigned char *) strchr((char *) star, '.')) != NULL)
+  {
+    star = sdot + 1;
+
+    n = strlen((char *) star);
+
+    if (n > 3)
+      *(star + 3) = '\0';
+  }
+}
+
+/* Following works on both null-terminated names */
+
+void retwiddle (unsigned char *s)
+{
+  while (*s != '\0')
+  {
+    if (*s == (unsigned char) pseudo_tilde)
+      *s = '~';
+    else if (*s == (unsigned char) pseudo_space)
+      *s = ' ';
+
+    s++;
+  }
+}
+
+boolean open_input (FILE ** f, kpse_file_format_type file_fmt, const char * fopen_mode)
+{
+  boolean openable = false;
+  char * file_name = NULL;
+
+#if defined (FUNNY_CORE_DUMP) && !defined (BibTeX)
+  if (file_fmt == kpse_tex_format &&
+    strncmp(name_of_file + 1, "HackyInputFileNameForCoreDump.tex", 33) == 0)
+    funny_core_dump();
+#endif
+
+  if (return_flag)
+  {
+    if (strcmp(fopen_mode, "r") == 0)
+      fopen_mode = "rb";
+  }
+
+  name_of_file[name_length + 1] = '\0';
+
+  /* reinsert '~' and ' ' in file names */  
+  if (pseudo_tilde != 0 || pseudo_space != 0)
+    retwiddle(name_of_file + 1);
+
+  if (shorten_file_name)
+    check_short_name(name_of_file + 1);
+  
+  if (open_trace_flag)
+    printf(" Open `%s' for input ", name_of_file + 1);
+
+  file_name = kpse_find_file((const_string) name_of_file + 1, file_fmt, false);
+
+  if (file_name != NULL)
+  {
+    strcpy ((char *) name_of_file + 1, file_name);
+    *f = xfopen((char *) file_name, fopen_mode);
+
+#ifdef _WIN32
+    if (name_of_file[1] == '.' && (name_of_file[2] == PATH_SEP || name_of_file[2] == '\\'))
+#else
+    if (name_of_file[1] == '.' && name_of_file[2] == PATH_SEP)
+#endif
+    {
+      unsigned i = 1;
+
+      while (name_of_file[i + 2] != '\0')
+      {
+        name_of_file[i] = name_of_file[i + 2];
+        i++;
+      }
+
+      name_of_file[i] = '\0';
+      name_length = i - 1;
+    }
+    else
+      name_length = strlen((char *) name_of_file + 1);
+      
+    if (file_fmt == kpse_tfm_format)
+    {
+      fbyte = getc(*f);
+    } 
+
+    if (strstr((char *) name_of_file + 1, ".fmt") != NULL)
+    {
+      if (format_file == NULL)
+        format_file = xstrdup((char *) name_of_file + 1);
+
+#ifdef COMPACTFORMAT
+      gz_fmt_file = gzdopen(fileno(*f), "rb9");
+#endif
+    }
+    else if (strstr((char *) name_of_file + 1, ".tfm") != NULL)
+    {
+      if (show_tfm_flag && log_opened)
+      {
+        int n; 
+        n = strlen((char *) name_of_file + 1);
+
+        if (file_offset + n > max_print_line)
+        {
+          (void) putc('\n', log_file);
+          file_offset = 0;
+        }
+        else
+          (void) putc(' ', log_file);
+
+        fprintf(log_file, "(%s)", name_of_file + 1);
+        file_offset += n + 3;
+      }
+    }
+    else if (source_direct == NULL)
+    {
+      char *s;
+
+      source_direct = xstrdup((char *) name_of_file + 1);
+
+      if (trace_flag)
+        printf("Methinks the source %s is `%s'\n", "file", source_direct);
+
+      if ((s = strrchr(source_direct, '/')) == NULL)
+        *source_direct = '\0';
+      else
+        *(s + 1) = '\0';
+
+      if (trace_flag)
+        printf("Methinks the source %s is `%s'\n", "directory", source_direct);
+    }
+
+    openable = true;
+  }
+
+  {
+    unsigned temp_length = strlen((char *) name_of_file + 1);
+    name_of_file[temp_length + 1] = ' ';
+  }
+
+  return openable;
+}
+
+/* At least check for I/O error (such as disk full) when closing */
+/* Would be better to check while writing - but this is better than nothing */
+/* This is used for both input and output files, but never mind ... */
+
+/* now a_close returns -1 on error --- which could be used by caller */
+/* probably want to ignore on input files ... */
+
+// check_fclose not used by anything
+int check_fclose (FILE * f)
+{
+  if (f == NULL)
+    return 0;
+
+  if (ferror(f) || fclose (f))
+  {
+    perrormod("\n! I/O Error");
+    uexit(EXIT_FAILURE);
+  }
+
+  return 0;
+}
+
+char * xstrdup_name (void)
+{
+  if (qualified(name_of_file + 1))
+    *log_line = '\0';
+  else
+  {
+    (void) getcwd(log_line, sizeof(log_line));
+    strcat(log_line, PATH_SEP_STRING);
+  }
+
+  strcat(log_line, (char *) name_of_file + 1);
+  unixify(log_line);
+  return xstrdup(log_line);
+}
+
+boolean open_output (FILE ** f, const char * fopen_mode)
+{
+  unsigned temp_length;
+
+  name_of_file[name_length + 1] = '\0';
+
+  if (pseudo_tilde != 0 || pseudo_space !=  0)
+    retwiddle(name_of_file + 1);
+
+  /* 8 + 3 file names on Windows NT 95/Feb/20 */
+  if (shorten_file_name)
+    check_short_name(name_of_file + 1);
+
+  if (prepend_path_if(name_of_file + 1, name_of_file + 1, ".dvi", dvi_directory) ||
+      prepend_path_if(name_of_file + 1, name_of_file + 1, ".log", log_directory) ||
+      prepend_path_if(name_of_file + 1, name_of_file + 1, ".aux", aux_directory) ||
+      prepend_path_if(name_of_file + 1, name_of_file + 1, ".fmt", fmt_directory) ||
+      prepend_path_if(name_of_file + 1, name_of_file + 1, ".pdf", pdf_directory))
+  {
+    if (open_trace_flag)
+      printf("After prepend %s\n", name_of_file + 1);
+  }
+
+  if (open_trace_flag)
+    printf(" Open `%s' for output ", name_of_file + 1);
+
+  *f = fopen((char *) name_of_file + 1, fopen_mode);
+
+  if (*f == NULL)
+  {
+    string temp_dir = kpse_var_value("TEXMFOUTPUT");
+
+    if (temp_dir != NULL)
+    {
+#ifdef BUILDNAMEDIRECT
+      unsigned char temp_name[file_name_size];
+      xconcat3((char *) temp_name, temp_dir, PATH_SEP_STRING, (char *) name_of_file + 1);
+#else
+      string temp_name = concat3(temp_dir, PATH_SEP_STRING, name_of_file + 1);
+#endif
+
+      if (deslash)
+        unixify((char *) temp_name);
+      
+      /* but we can assume this is opening here for *output* */
+      *f = fopen((char *) temp_name, fopen_mode);
+      /* If this succeeded, change name_of_file accordingly. */
+      if (*f)
+        strcpy((char *) name_of_file + 1, (char *) temp_name);
+
+#ifndef BUILDNAMEDIRECT
+      free (temp_name);
+#endif
+    }
+  }
+
+#ifdef COMPACTFORMAT
+  if (strstr((char *) name_of_file + 1, ".fmt") != NULL)
+    gz_fmt_file = gzdopen(fileno(*f), "wb9");
+#endif
+
+  if (strstr((char *) name_of_file + 1, ".dvi") != NULL)
+    dvi_file_name = xstrdup_name();
+  else if (strstr((char *) name_of_file + 1, ".pdf") != NULL)
+    pdf_file_name = xstrdup_name();
+  else if (strstr((char *) name_of_file + 1, ".log") != NULL)
+    log_file_name = xstrdup_name();
+
+  temp_length = strlen((char *) name_of_file + 1);
+  name_of_file[temp_length + 1] = ' ';
+
+  if (*f)
+    name_length = temp_length;
+  
+  return (*f != NULL);
 }
\ No newline at end of file