+/* -------------------------------------------------------------------------- **
+ * 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 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * -------------------------------------------------------------------------- **
+ *
+ * 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"
+
+extern BOOL in_client;
+
+/* -------------------------------------------------------------------------- **
+ * Constants...
+ */
+
+#define BUFR_INC 1024
+
+
+/* -------------------------------------------------------------------------- **
+ * Variables...
+ *
+ * DEBUGLEVEL - The ubiquitous DEBUGLEVEL. This determines which DEBUG()
+ * messages will be produced.
+ * bufr - pointer to a global buffer. This is probably a kludge,
+ * but it was the nicest kludge I could think of (for now).
+ * bSize - The size of the global buffer <bufr>.
+ */
+
+static char *bufr = NULL;
+static int bSize = 0;
+
+/* 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 *end_section_p;
+} 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)
+{
+ if (!f)
+ return;
+ SAFE_FREE(f->buf);
+ SAFE_FREE(f);
+}
+
+/* Find the end of the section. We must use mb functions for this. */
+static int FindSectionEnd(myFILE *f)
+{
+ f->end_section_p = strchr_m(f->p, ']');
+ return f->end_section_p ? 1 : 0;
+}
+
+static int AtSectionEnd(myFILE *f)
+{
+ if (f->p == f->end_section_p + 1) {
+ f->end_section_p = NULL;
+ return 1;
+ }
+ return 0;
+}
+
+/* -------------------------------------------------------------------------- **
+ * Functions...
+ */
+ /* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static int EatWhitespace( myFILE *InFile )
+{
+ int c;
+
+ for( c = mygetc( InFile ); isspace( c ) && ('\n' != c); c = mygetc( InFile ) )
+ ;
+ return( c );
+}
+
+ /* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static int EatComment( myFILE *InFile )
+{
+ int c;
+
+ for( c = mygetc( InFile ); ('\n'!=c) && (EOF!=c) && (c>0); c = mygetc( InFile ) )
+ ;
+ return( c );
+}
+
+/*****************************************************************************
+ * 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 );
+}
+
+/* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static BOOL Section( myFILE *InFile, BOOL (*sfunc)(const char *) )
+{
+ 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>. */
+
+
+ /* Find the end of the section. We must use mb functions for this. */
+ if (!FindSectionEnd(InFile)) {
+ DEBUG(0, ("%s No terminating ']' character in section.\n", func) );
+ return False;
+ }
+
+ 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 > (bSize - 2) ) {
+ char *tb;
+
+ tb = (char *)SMB_REALLOC( bufr, bSize +BUFR_INC );
+ if( NULL == tb ) {
+ DEBUG(0, ("%s Memory re-allocation failure.", func) );
+ return False;
+ }
+ bufr = tb;
+ bSize += BUFR_INC;
+ }
+
+ /* Handle a single character other than section end. */
+ switch( c ) {
+ case '\n': /* Got newline before closing ']'. */
+ i = Continuation( bufr, i ); /* Check for line continuation. */
+ if( i < 0 ) {
+ bufr[end] = '\0';
+ DEBUG(0, ("%s Badly formed line in configuration file: %s\n", func, bufr ));
+ return False;
+ }
+ end = ( (i > 0) && (' ' == 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. */
+ bufr[end] = ' ';
+ i = end + 1;
+ c = EatWhitespace( InFile );
+ } else {
+ bufr[i++] = c;
+ end = i;
+ c = mygetc( InFile );
+ }
+ }
+
+ if (AtSectionEnd(InFile)) {
+ /* Got to the closing bracket. */
+ 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(bufr) ) /* Got a valid name. Deal with it. */
+ return False;
+ EatComment( InFile ); /* Finish off the line. */
+ return True;
+ }
+
+ }
+
+ /* We arrive here if we've met the EOF before the closing bracket. */
+ DEBUG(0, ("%s Unexpected EOF in the configuration file: %s\n", func, bufr ));
+ return False;
+}
+
+/* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static BOOL Parameter( myFILE *InFile, BOOL (*pfunc)(const char *, const char *), int c )
+{
+ 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 > (bSize - 2) ) {
+ /* Ensure there's space for next char. */
+ char *tb = (char *)SMB_REALLOC( bufr, bSize + BUFR_INC );
+ if( NULL == tb ) {
+ DEBUG(0, ("%s Memory re-allocation failure.", func) );
+ return False;
+ }
+ bufr = tb;
+ 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;
+ }
+ bufr[end++] = '\0'; /* Mark end of string & advance. */
+ i = end; /* New string starts here. */
+ vstart = end; /* New string is parameter value. */
+ bufr[i] = '\0'; /* New string is nul, for now. */
+ break;
+
+ case '\n': /* Find continuation char, else error. */
+ i = Continuation( bufr, i );
+ if( i < 0 ) {
+ bufr[end] = '\0';
+ DEBUG(1,("%s Ignoring badly formed line in configuration file: %s\n", func, bufr ));
+ return True;
+ }
+ end = ( (i > 0) && (' ' == bufr[i - 1]) ) ? (i - 1) : (i);
+ c = mygetc( InFile ); /* Read past eoln. */
+ break;
+
+ case '\0': /* Shouldn't have EOF within param name. */
+ case EOF:
+ bufr[i] = '\0';
+ DEBUG(1,("%s Unexpected end-of-file at: %s\n", func, bufr ));
+ return True;
+
+ default:
+ if(isspace( c )) {
+ /* One ' ' per whitespace region. */
+ bufr[end] = ' ';
+ i = end + 1;
+ c = EatWhitespace( InFile );
+ } else {
+ 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 > (bSize - 2) ) {
+ /* Make sure there's enough room. */
+ char *tb = (char *)SMB_REALLOC( bufr, bSize + BUFR_INC );
+ if( NULL == tb ) {
+ DEBUG(0, ("%s Memory re-allocation failure.", func));
+ return False;
+ }
+ bufr = tb;
+ 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( bufr, i );
+ if( i < 0 ) {
+ c = 0;
+ } else {
+ for( end = i; (end >= 0) && isspace((int)bufr[end]); end-- )
+ ;
+ c = mygetc( InFile );
+ }
+ break;
+
+ default: /* All others verbatim. Note that spaces do not advance <end>. This allows trimming */
+ bufr[i++] = c;
+ if( !isspace( c ) ) /* of whitespace at the end of the line. */
+ end = i;
+ c = mygetc( InFile );
+ break;
+ }
+ }
+ bufr[end] = '\0'; /* End of value. */
+
+ return( pfunc( bufr, &bufr[vstart] ) ); /* Pass name & value to pfunc(). */
+}
+
+/* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static BOOL Parse( myFILE *InFile,
+ BOOL (*sfunc)(const char *),
+ BOOL (*pfunc)(const char *, const char *) )
+{
+ 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 ) )
+ return False;
+ c = EatWhitespace( InFile );
+ break;
+
+ case '\\': /* Bogus backslash. */
+ c = EatWhitespace( InFile );
+ break;
+
+ default: /* Parameter line. */
+ if( !Parameter( InFile, pfunc, c ) )
+ return False;
+ c = EatWhitespace( InFile );
+ break;
+ }
+ }
+ return True;
+}
+
+/* ------------------------------------------------------------------------ **
+ * 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
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+static myFILE *OpenConfFile( const char *FileName )
+{
+ const char *func = "params.c:OpenConfFile() -";
+ int lvl = in_client?1:0;
+ myFILE *ret;
+
+ ret = SMB_MALLOC_P(myFILE);
+ if (!ret)
+ return NULL;
+
+ ret->buf = file_load(FileName, &ret->size);
+ if( NULL == ret->buf ) {
+ DEBUG( lvl, ("%s Unable to open configuration file \"%s\":\n\t%s\n",
+ func, FileName, strerror(errno)) );
+ SAFE_FREE(ret);
+ return NULL;
+ }
+
+ ret->p = ret->buf;
+ ret->end_section_p = NULL;
+ return( ret );
+}
+
+/* ------------------------------------------------------------------------ **
+ * 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.
+ *
+ * ------------------------------------------------------------------------ **
+ */
+
+BOOL pm_process( const char *FileName,
+ BOOL (*sfunc)(const char *),
+ BOOL (*pfunc)(const char *, const char *) )
+{
+ 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 != bufr ) {
+ /* If we already have a buffer */
+ /* (recursive call), then just */
+ /* use it. */
+ result = Parse( InFile, sfunc, pfunc );
+ } else {
+ bSize = BUFR_INC;
+ bufr = (char *)SMB_MALLOC( bSize );
+ if( NULL == bufr ) {
+ DEBUG(0,("%s memory allocation failure.\n", func));
+ myfile_close(InFile);
+ return False;
+ }
+
+ result = Parse( InFile, sfunc, pfunc );
+ SAFE_FREE( bufr );
+ bufr = NULL;
+ bSize = 0;
+ }
+
+ myfile_close(InFile);
+
+ if( !result ) {
+ DEBUG(0,("%s Failed. Error returned from params.c:parse().\n", func));
+ return False;
+ }
+
+ return True;
+}
projects / samba / blobdiff