Re-add params file to git.

(This used to be commit fc50e78e2631e8253571bc236302e2859e4d1559)

1 files changed, 587 insertions, 0 deletions

diff --git a/source4/lib/util/params.c b/source4/lib/util/params.c
new file mode 100644
index 0000000000..3a9e2b9505
--- /dev/null
+++ b/source4/lib/util/params.c
@@ -0,0 +1,587 @@
+/* -------------------------------------------------------------------------- **
+ * Microsoft Network Services for Unix, AKA., Andrew Tridgell's SAMBA.
+ *
+ * This module Copyright (C) 1990-1998 Karl Auer
+ *
+ * Rewritten almost completely by Christopher R. Hertel
+ * at the University of Minnesota, September, 1997.
+ * This module Copyright (C) 1997-1998 by the University of Minnesota
+ * -------------------------------------------------------------------------- **
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ * -------------------------------------------------------------------------- **
+ *
+ * Module name: params
+ *
+ * -------------------------------------------------------------------------- **
+ *
+ *  This module performs lexical analysis and initial parsing of a
+ *  Windows-like parameter file.  It recognizes and handles four token
+ *  types:  section-name, parameter-name, parameter-value, and
+ *  end-of-file.  Comments and line continuation are handled
+ *  internally.
+ *
+ *  The entry point to the module is function pm_process().  This
+ *  function opens the source file, calls the Parse() function to parse
+ *  the input, and then closes the file when either the EOF is reached
+ *  or a fatal error is encountered.
+ *
+ *  A sample parameter file might look like this:
+ *
+ *  [section one]
+ *  parameter one = value string
+ *  parameter two = another value
+ *  [section two]
+ *  new parameter = some value or t'other
+ *
+ *  The parameter file is divided into sections by section headers:
+ *  section names enclosed in square brackets (eg. [section one]).
+ *  Each section contains parameter lines, each of which consist of a
+ *  parameter name and value delimited by an equal sign.  Roughly, the
+ *  syntax is:
+ *
+ *    <file>            :==  { <section> } EOF
+ *
+ *    <section>         :==  <section header> { <parameter line> }
+ *
+ *    <section header>  :==  '[' NAME ']'
+ *
+ *    <parameter line>  :==  NAME '=' VALUE '\n'
+ *
+ *  Blank lines and comment lines are ignored.  Comment lines are lines
+ *  beginning with either a semicolon (';') or a pound sign ('#').
+ *
+ *  All whitespace in section names and parameter names is compressed
+ *  to single spaces.  Leading and trailing whitespace is stipped from
+ *  both names and values.
+ *
+ *  Only the first equals sign in a parameter line is significant.
+ *  Parameter values may contain equals signs, square brackets and
+ *  semicolons.  Internal whitespace is retained in parameter values,
+ *  with the exception of the '\r' character, which is stripped for
+ *  historic reasons.  Parameter names may not start with a left square
+ *  bracket, an equal sign, a pound sign, or a semicolon, because these
+ *  are used to identify other tokens.
+ *
+ * -------------------------------------------------------------------------- **
+ */
+
+#include "includes.h"
+#include "system/locale.h"
+
+/* -------------------------------------------------------------------------- **
+ * Constants...
+ */
+
+#define BUFR_INC 1024
+
+
+/* we can't use FILE* due to the 256 fd limit - use this cheap hack
+   instead */
+typedef struct {
+	char *buf;
+	char *p;
+	size_t size;
+	char *bufr;
+	int   bSize;
+} myFILE;
+
+static int mygetc(myFILE *f)
+{
+	if (f->p >= f->buf+f->size) return EOF;
+        /* be sure to return chars >127 as positive values */
+	return (int)( *(f->p++) & 0x00FF );
+}
+
+static void myfile_close(myFILE *f)
+{
+	talloc_free(f);
+}
+
+/* -------------------------------------------------------------------------- **
+ * Functions...
+ */
+
+static int EatWhitespace( myFILE *InFile )
+  /* ------------------------------------------------------------------------ **
+   * Scan past whitespace (see ctype(3C)) and return the first non-whitespace
+   * character, or newline, or EOF.
+   *
+   *  Input:  InFile  - Input source.
+   *
+   *  Output: The next non-whitespace character in the input stream.
+   *
+   *  Notes:  Because the config files use a line-oriented grammar, we
+   *          explicitly exclude the newline character from the list of
+   *          whitespace characters.
+   *        - Note that both EOF (-1) and the nul character ('\0') are
+   *          considered end-of-file markers.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int c;
+
+  for( c = mygetc( InFile ); isspace( c ) && ('\n' != c); c = mygetc( InFile ) )
+    ;
+  return( c );
+  } /* EatWhitespace */
+
+static int EatComment( myFILE *InFile )
+  /* ------------------------------------------------------------------------ **
+   * Scan to the end of a comment.
+   *
+   *  Input:  InFile  - Input source.
+   *
+   *  Output: The character that marks the end of the comment.  Normally,
+   *          this will be a newline, but it *might* be an EOF.
+   *
+   *  Notes:  Because the config files use a line-oriented grammar, we
+   *          explicitly exclude the newline character from the list of
+   *          whitespace characters.
+   *        - Note that both EOF (-1) and the nul character ('\0') are
+   *          considered end-of-file markers.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int c;
+
+  for( c = mygetc( InFile ); ('\n'!=c) && (EOF!=c) && (c>0); c = mygetc( InFile ) )
+    ;
+  return( c );
+  } /* EatComment */
+
+/*****************************************************************************
+ * Scan backards within a string to discover if the last non-whitespace
+ * character is a line-continuation character ('\\').
+ *
+ *  Input:  line  - A pointer to a buffer containing the string to be
+ *                  scanned.
+ *          pos   - This is taken to be the offset of the end of the
+ *                  string.  This position is *not* scanned.
+ *
+ *  Output: The offset of the '\\' character if it was found, or -1 to
+ *          indicate that it was not.
+ *
+ *****************************************************************************/
+
+static int Continuation(char *line, int pos )
+{
+	pos--;
+	while( (pos >= 0) && isspace((int)line[pos]))
+		pos--;
+
+	return (((pos >= 0) && ('\\' == line[pos])) ? pos : -1 );
+}
+
+
+static bool Section( myFILE *InFile, bool (*sfunc)(const char *, void *), void *userdata )
+  /* ------------------------------------------------------------------------ **
+   * Scan a section name, and pass the name to function sfunc().
+   *
+   *  Input:  InFile  - Input source.
+   *          sfunc   - Pointer to the function to be called if the section
+   *                    name is successfully read.
+   *
+   *  Output: true if the section name was read and true was returned from
+   *          <sfunc>.  false if <sfunc> failed or if a lexical error was
+   *          encountered.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   c;
+  int   i;
+  int   end;
+  const char *func  = "params.c:Section() -";
+
+  i = 0;      /* <i> is the offset of the next free byte in bufr[] and  */
+  end = 0;    /* <end> is the current "end of string" offset.  In most  */
+              /* cases these will be the same, but if the last          */
+              /* character written to bufr[] is a space, then <end>     */
+              /* will be one less than <i>.                             */
+
+  c = EatWhitespace( InFile );    /* We've already got the '['.  Scan */
+                                  /* past initial white space.        */
+
+  while( (EOF != c) && (c > 0) )
+    {
+
+    /* Check that the buffer is big enough for the next character. */
+    if( i > (InFile->bSize - 2) )
+      {
+      char *tb;
+      
+      tb = talloc_realloc(InFile, InFile->bufr, char, InFile->bSize + BUFR_INC);
+      if( NULL == tb )
+        {
+        DEBUG(0, ("%s Memory re-allocation failure.", func) );
+        return( false );
+        }
+      InFile->bufr = tb;
+      InFile->bSize += BUFR_INC;
+      }
+
+    /* Handle a single character. */
+    switch( c )
+      {
+      case ']':                       /* Found the closing bracket.         */
+        InFile->bufr[end] = '\0';
+        if( 0 == end )                  /* Don't allow an empty name.       */
+          {
+          DEBUG(0, ("%s Empty section name in configuration file.\n", func ));
+          return( false );
+          }
+        if( !sfunc(InFile->bufr,userdata) )            /* Got a valid name.  Deal with it. */
+          return( false );
+        (void)EatComment( InFile );     /* Finish off the line.             */
+        return( true );
+
+      case '\n':                      /* Got newline before closing ']'.    */
+        i = Continuation( InFile->bufr, i );    /* Check for line continuation.     */
+        if( i < 0 )
+          {
+          InFile->bufr[end] = '\0';
+          DEBUG(0, ("%s Badly formed line in configuration file: %s\n",
+                   func, InFile->bufr ));
+          return( false );
+          }
+        end = ( (i > 0) && (' ' == InFile->bufr[i - 1]) ) ? (i - 1) : (i);
+        c = mygetc( InFile );             /* Continue with next line.         */
+        break;
+
+      default:                        /* All else are a valid name chars.   */
+        if( isspace( c ) )              /* One space per whitespace region. */
+          {
+          InFile->bufr[end] = ' ';
+          i = end + 1;
+          c = EatWhitespace( InFile );
+          }
+        else                            /* All others copy verbatim.        */
+          {
+          InFile->bufr[i++] = c;
+          end = i;
+          c = mygetc( InFile );
+          }
+      }
+    }
+
+  /* We arrive here if we've met the EOF before the closing bracket. */
+  DEBUG(0, ("%s Unexpected EOF in the configuration file\n", func));
+  return( false );
+  } /* Section */
+
+static bool Parameter( myFILE *InFile, bool (*pfunc)(const char *, const char *, void *), int c, void *userdata )
+  /* ------------------------------------------------------------------------ **
+   * Scan a parameter name and value, and pass these two fields to pfunc().
+   *
+   *  Input:  InFile  - The input source.
+   *          pfunc   - A pointer to the function that will be called to
+   *                    process the parameter, once it has been scanned.
+   *          c       - The first character of the parameter name, which
+   *                    would have been read by Parse().  Unlike a comment
+   *                    line or a section header, there is no lead-in
+   *                    character that can be discarded.
+   *
+   *  Output: true if the parameter name and value were scanned and processed
+   *          successfully, else false.
+   *
+   *  Notes:  This function is in two parts.  The first loop scans the
+   *          parameter name.  Internal whitespace is compressed, and an
+   *          equal sign (=) terminates the token.  Leading and trailing
+   *          whitespace is discarded.  The second loop scans the parameter
+   *          value.  When both have been successfully identified, they are
+   *          passed to pfunc() for processing.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   i       = 0;    /* Position within bufr. */
+  int   end     = 0;    /* bufr[end] is current end-of-string. */
+  int   vstart  = 0;    /* Starting position of the parameter value. */
+  const char *func    = "params.c:Parameter() -";
+
+  /* Read the parameter name. */
+  while( 0 == vstart )  /* Loop until we've found the start of the value. */
+    {
+
+    if( i > (InFile->bSize - 2) )       /* Ensure there's space for next char.    */
+      {
+      char *tb;
+      
+      tb = talloc_realloc(InFile, InFile->bufr, char, InFile->bSize + BUFR_INC );
+      if( NULL == tb )
+        {
+        DEBUG(0, ("%s Memory re-allocation failure.", func) );
+        return( false );
+        }
+      InFile->bufr = tb;
+      InFile->bSize += BUFR_INC;
+      }
+
+    switch( c )
+      {
+      case '=':                 /* Equal sign marks end of param name. */
+        if( 0 == end )              /* Don't allow an empty name.      */
+          {
+          DEBUG(0, ("%s Invalid parameter name in config. file.\n", func ));
+          return( false );
+          }
+        InFile->bufr[end++] = '\0';         /* Mark end of string & advance.   */
+        i       = end;              /* New string starts here.         */
+        vstart  = end;              /* New string is parameter value.  */
+        InFile->bufr[i] = '\0';             /* New string is nul, for now.     */
+        break;
+
+      case '\n':                /* Find continuation char, else error. */
+        i = Continuation( InFile->bufr, i );
+        if( i < 0 )
+          {
+          InFile->bufr[end] = '\0';
+          DEBUG(1,("%s Ignoring badly formed line in configuration file: %s\n",
+                   func, InFile->bufr ));
+          return( true );
+          }
+        end = ( (i > 0) && (' ' == InFile->bufr[i - 1]) ) ? (i - 1) : (i);
+        c = mygetc( InFile );       /* Read past eoln.                   */
+        break;
+
+      case '\0':                /* Shouldn't have EOF within param name. */
+      case EOF:
+        InFile->bufr[i] = '\0';
+        DEBUG(1,("%s Unexpected end-of-file at: %s\n", func, InFile->bufr ));
+        return( true );
+
+      default:
+        if( isspace( c ) )     /* One ' ' per whitespace region.       */
+          {
+          InFile->bufr[end] = ' ';
+          i = end + 1;
+          c = EatWhitespace( InFile );
+          }
+        else                   /* All others verbatim.                 */
+          {
+          InFile->bufr[i++] = c;
+          end = i;
+          c = mygetc( InFile );
+          }
+      }
+    }
+
+  /* Now parse the value. */
+  c = EatWhitespace( InFile );  /* Again, trim leading whitespace. */
+  while( (EOF !=c) && (c > 0) )
+    {
+
+    if( i > (InFile->bSize - 2) )       /* Make sure there's enough room. */
+      {
+      char *tb;
+      
+      tb = talloc_realloc(InFile, InFile->bufr, char, InFile->bSize + BUFR_INC );
+      if( NULL == tb )
+        {
+        DEBUG(0, ("%s Memory re-allocation failure.", func) );
+        return( false );
+        }
+      InFile->bufr = tb;
+      InFile->bSize += BUFR_INC;
+      }
+
+    switch( c )
+      {
+      case '\r':              /* Explicitly remove '\r' because the older */
+        c = mygetc( InFile );   /* version called fgets_slash() which also  */
+        break;                /* removes them.                            */
+
+      case '\n':              /* Marks end of value unless there's a '\'. */
+        i = Continuation( InFile->bufr, i );
+        if( i < 0 )
+          c = 0;
+        else
+          {
+          for( end = i; (end >= 0) && isspace((int)InFile->bufr[end]); end-- )
+            ;
+          c = mygetc( InFile );
+          }
+        break;
+
+      default:               /* All others verbatim.  Note that spaces do */
+        InFile->bufr[i++] = c;       /* not advance <end>.  This allows trimming  */
+        if( !isspace( c ) )  /* of whitespace at the end of the line.     */
+          end = i;
+        c = mygetc( InFile );
+        break;
+      }
+    }
+  InFile->bufr[end] = '\0';          /* End of value. */
+
+  return( pfunc( InFile->bufr, &InFile->bufr[vstart], userdata ) );   /* Pass name & value to pfunc().  */
+  } /* Parameter */
+
+static bool Parse( myFILE *InFile,
+                   bool (*sfunc)(const char *, void *),
+                   bool (*pfunc)(const char *, const char *, void *),
+				   void *userdata )
+  /* ------------------------------------------------------------------------ **
+   * Scan & parse the input.
+   *
+   *  Input:  InFile  - Input source.
+   *          sfunc   - Function to be called when a section name is scanned.
+   *                    See Section().
+   *          pfunc   - Function to be called when a parameter is scanned.
+   *                    See Parameter().
+   *
+   *  Output: true if the file was successfully scanned, else false.
+   *
+   *  Notes:  The input can be viewed in terms of 'lines'.  There are four
+   *          types of lines:
+   *            Blank      - May contain whitespace, otherwise empty.
+   *            Comment    - First non-whitespace character is a ';' or '#'.
+   *                         The remainder of the line is ignored.
+   *            Section    - First non-whitespace character is a '['.
+   *            Parameter  - The default case.
+   * 
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int    c;
+
+  c = EatWhitespace( InFile );
+  while( (EOF != c) && (c > 0) )
+    {
+    switch( c )
+      {
+      case '\n':                        /* Blank line. */
+        c = EatWhitespace( InFile );
+        break;
+
+      case ';':                         /* Comment line. */
+      case '#':
+        c = EatComment( InFile );
+        break;
+
+      case '[':                         /* Section Header. */
+        if( !Section( InFile, sfunc, userdata ) )
+          return( false );
+        c = EatWhitespace( InFile );
+        break;
+
+      case '\\':                        /* Bogus backslash. */
+        c = EatWhitespace( InFile );
+        break;
+
+      default:                          /* Parameter line. */
+        if( !Parameter( InFile, pfunc, c, userdata ) )
+          return( false );
+        c = EatWhitespace( InFile );
+        break;
+      }
+    }
+  return( true );
+  } /* Parse */
+
+static myFILE *OpenConfFile( const char *FileName )
+  /* ------------------------------------------------------------------------ **
+   * Open a configuration file.
+   *
+   *  Input:  FileName  - The pathname of the config file to be opened.
+   *
+   *  Output: A pointer of type (char **) to the lines of the file
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  const char *func = "params.c:OpenConfFile() -";
+  myFILE *ret;
+
+  ret = talloc(talloc_autofree_context(), myFILE);
+  if (!ret) return NULL;
+
+  ret->buf = file_load(FileName, &ret->size, ret);
+  if( NULL == ret->buf )
+    {
+    DEBUG( 1,
+      ("%s Unable to open configuration file \"%s\":\n\t%s\n",
+      func, FileName, strerror(errno)) );
+    talloc_free(ret);
+    return NULL;
+    }
+
+  ret->p = ret->buf;
+  ret->bufr = NULL;
+  ret->bSize = 0;
+  return( ret );
+  } /* OpenConfFile */
+
+bool pm_process( const char *FileName,
+                 bool (*sfunc)(const char *, void *),
+                 bool (*pfunc)(const char *, const char *, void *),
+				 void *userdata)
+  /* ------------------------------------------------------------------------ **
+   * Process the named parameter file.
+   *
+   *  Input:  FileName  - The pathname of the parameter file to be opened.
+   *          sfunc     - A pointer to a function that will be called when
+   *                      a section name is discovered.
+   *          pfunc     - A pointer to a function that will be called when
+   *                      a parameter name and value are discovered.
+   *
+   *  Output: TRUE if the file was successfully parsed, else FALSE.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   result;
+  myFILE *InFile;
+  const char *func = "params.c:pm_process() -";
+
+  InFile = OpenConfFile( FileName );          /* Open the config file. */
+  if( NULL == InFile )
+    return( false );
+
+  DEBUG( 3, ("%s Processing configuration file \"%s\"\n", func, FileName) );
+
+  if( NULL != InFile->bufr )                          /* If we already have a buffer */
+    result = Parse( InFile, sfunc, pfunc, userdata );   /* (recursive call), then just */
+                                              /* use it.                     */
+
+  else                                        /* If we don't have a buffer   */
+    {                                         /* allocate one, then parse,   */
+    InFile->bSize = BUFR_INC;                         /* then free.                  */
+    InFile->bufr = talloc_array(InFile, char, InFile->bSize );
+    if( NULL == InFile->bufr )
+      {
+      DEBUG(0,("%s memory allocation failure.\n", func));
+      myfile_close(InFile);
+      return( false );
+      }
+    result = Parse( InFile, sfunc, pfunc, userdata );
+    InFile->bufr  = NULL;
+    InFile->bSize = 0;
+    }
+
+  myfile_close(InFile);
+
+  if( !result )                               /* Generic failure. */
+    {
+    DEBUG(0,("%s Failed.  Error returned from params.c:parse().\n", func));
+    return( false );
+    }
+
+  return( true );                             /* Generic success. */
+  } /* pm_process */
+
+/* -------------------------------------------------------------------------- */