configuration parsing and loading code for rsyncd. This is based

[rsync/rsync.git] / loadparm.c

/* This is based on loadparm.c from Samba, written by Andrew Tridgell
   and Karl Auer */

/* 
   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.
*/

/*
 *  Load parameters.
 *
 *  This module provides suitable callback functions for the params
 *  module. It builds the internal table of service details which is
 *  then used by the rest of the server.
 *
 * To add a parameter:
 *
 * 1) add it to the global or service structure definition
 * 2) add it to the parm_table
 * 3) add it to the list of available functions (eg: using FN_GLOBAL_STRING())
 * 4) If it's a global then initialise it in init_globals. If a local
 *    (ie. service) parameter then initialise it in the sDefault structure
 *  
 *
 * Notes:
 *   The configuration file is processed sequentially for speed. It is NOT
 *   accessed randomly as happens in 'real' Windows. For this reason, there
 *   is a fair bit of sequence-dependent code here - ie., code which assumes
 *   that certain things happen before others. In particular, the code which
 *   happens at the boundary between sections is delicately poised, so be
 *   careful!
 *
 */

#include "rsync.h"
#define BOOL int
#define False 0
#define True 1
#define Realloc realloc
#define PTR_DIFF(p1,p2) ((ptrdiff_t)(((char *)(p1)) - (char *)(p2)))
#define strequal(a,b) (strcasecmp(a,b)==0)
#define BOOLSTR(b) ((b) ? "Yes" : "No")
typedef char pstring[1024];
#define pstrcpy(a,b) strcpy(a,b)

/* the following are used by loadparm for option lists */
typedef enum
{
  P_BOOL,P_BOOLREV,P_CHAR,P_INTEGER,P_OCTAL,
  P_STRING,P_GSTRING,P_ENUM,P_SEP
} parm_type;

typedef enum
{
  P_LOCAL,P_GLOBAL,P_SEPARATOR,P_NONE
} parm_class;

struct enum_list {
	int value;
	char *name;
};

struct parm_struct
{
	char *label;
	parm_type type;
	parm_class class;
	void *ptr;
	struct enum_list *enum_list;
	unsigned flags;
};

static BOOL bLoaded = False;

#ifndef GLOBAL_NAME
#define GLOBAL_NAME "global"
#endif

/* some helpful bits */
#define pSERVICE(i) ServicePtrs[i]
#define iSERVICE(i) (*pSERVICE(i))
#define LP_SNUM_OK(iService) (((iService) >= 0) && ((iService) < iNumServices))

/* 
 * This structure describes global (ie., server-wide) parameters.
 */
typedef struct
{
	char *motd_file;
} global;

static global Globals;



/* 
 * This structure describes a single service. 
 */
typedef struct
{
	char *name;
	char *path;
	char *comment;
	BOOL read_only;
	BOOL list;
	int uid;
	int gid;
} service;


/* This is a default service used to prime a services structure */
static service sDefault = 
{
	NULL,    /* name */
	NULL,    /* path */
	NULL,    /* comment */
	True,    /* read only */
	True,    /* list */
	-2,      /* uid */
	-2,      /* gid */
};



/* local variables */
static service **ServicePtrs = NULL;
static int iNumServices = 0;
static int iServiceIndex = 0;
static BOOL bInGlobalSection = True;

#define NUMPARAMETERS (sizeof(parm_table) / sizeof(struct parm_struct))


/* note that we do not initialise the defaults union - it is not allowed in ANSI C */
static struct parm_struct parm_table[] =
{
  {"motd file",        P_STRING,  P_GLOBAL, &Globals.motd_file,    NULL,   0},
  {"name",             P_STRING,  P_LOCAL,  &sDefault.name,        NULL,   0},
  {"comment",          P_STRING,  P_LOCAL,  &sDefault.comment,     NULL,   0},
  {"path",             P_STRING,  P_LOCAL,  &sDefault.path,        NULL,   0},
  {"read only",        P_BOOL,    P_LOCAL,  &sDefault.read_only,   NULL,   0},
  {"list",             P_BOOL,    P_LOCAL,  &sDefault.list,        NULL,   0},
  {"uid",              P_INTEGER, P_LOCAL,  &sDefault.uid,         NULL,   0},
  {"gid",              P_INTEGER, P_LOCAL,  &sDefault.gid,         NULL,   0},
  {NULL,               P_BOOL,    P_NONE,   NULL,                  NULL,   0}
};


/***************************************************************************
Initialise the global parameter structure.
***************************************************************************/
static void init_globals(void)
{
}

/***************************************************************************
Initialise the sDefault parameter structure.
***************************************************************************/
static void init_locals(void)
{
}


/*
   In this section all the functions that are used to access the 
   parameters from the rest of the program are defined 
*/

#define FN_GLOBAL_STRING(fn_name,ptr) \
 char *fn_name(void) {return(*(char **)(ptr) ? *(char **)(ptr) : "");}
#define FN_GLOBAL_BOOL(fn_name,ptr) \
 BOOL fn_name(void) {return(*(BOOL *)(ptr));}
#define FN_GLOBAL_CHAR(fn_name,ptr) \
 char fn_name(void) {return(*(char *)(ptr));}
#define FN_GLOBAL_INTEGER(fn_name,ptr) \
 int fn_name(void) {return(*(int *)(ptr));}

#define FN_LOCAL_STRING(fn_name,val) \
 char *fn_name(int i) {return((LP_SNUM_OK(i)&&pSERVICE(i)->val)?pSERVICE(i)->val : (sDefault.val?sDefault.val:""));}
#define FN_LOCAL_BOOL(fn_name,val) \
 BOOL fn_name(int i) {return(LP_SNUM_OK(i)? pSERVICE(i)->val : sDefault.val);}
#define FN_LOCAL_CHAR(fn_name,val) \
 char fn_name(int i) {return(LP_SNUM_OK(i)? pSERVICE(i)->val : sDefault.val);}
#define FN_LOCAL_INTEGER(fn_name,val) \
 int fn_name(int i) {return(LP_SNUM_OK(i)? pSERVICE(i)->val : sDefault.val);}


FN_GLOBAL_STRING(lp_motd_file, &Globals.motd_file)
FN_LOCAL_STRING(lp_name, name)
FN_LOCAL_STRING(lp_comment, comment)
FN_LOCAL_STRING(lp_path, path)
FN_LOCAL_BOOL(lp_read_only, read_only)
FN_LOCAL_BOOL(lp_list, list)
FN_LOCAL_INTEGER(lp_uid, uid)
FN_LOCAL_INTEGER(lp_gid, gid)

/* local prototypes */
static int    strwicmp( char *psz1, char *psz2 );
static int    map_parameter( char *parmname);
static BOOL   set_boolean( BOOL *pb, char *parmvalue );
static int    getservicebyname(char *name, service *pserviceDest);
static void   copy_service( service *pserviceDest, 
                            service *pserviceSource);
static BOOL   do_parameter(char *parmname, char *parmvalue);
static BOOL   do_section(char *sectionname);


/***************************************************************************
initialise a service to the defaults
***************************************************************************/
static void init_service(service *pservice)
{
  bzero((char *)pservice,sizeof(service));
  copy_service(pservice,&sDefault);
}

static void string_set(char **s, char *v)
{
	if (*s) free(*s);
	if (!v) {
		*s = NULL;
		return;
	}
	*s = strdup(v);
	if (!*s) exit_cleanup(1);
}


/***************************************************************************
add a new service to the services array initialising it with the given 
service
***************************************************************************/
static int add_a_service(service *pservice, char *name)
{
  int i;
  service tservice;
  int num_to_alloc = iNumServices+1;

  tservice = *pservice;

  /* it might already exist */
  if (name) 
    {
      i = getservicebyname(name,NULL);
      if (i >= 0)
	return(i);
    }

  i = iNumServices;

  ServicePtrs = (service **)Realloc(ServicePtrs,sizeof(service *)*num_to_alloc);
  if (ServicePtrs)
	  pSERVICE(iNumServices) = (service *)malloc(sizeof(service));

  if (!ServicePtrs || !pSERVICE(iNumServices))
	  return(-1);

  iNumServices++;

  init_service(pSERVICE(i));
  copy_service(pSERVICE(i),&tservice);
  if (name)
    string_set(&iSERVICE(i).name,name);  

  return(i);
}

/***************************************************************************
Do a case-insensitive, whitespace-ignoring string compare.
***************************************************************************/
static int strwicmp(char *psz1, char *psz2)
{
   /* if BOTH strings are NULL, return TRUE, if ONE is NULL return */
   /* appropriate value. */
   if (psz1 == psz2)
      return (0);
   else
      if (psz1 == NULL)
         return (-1);
      else
          if (psz2 == NULL)
              return (1);

   /* sync the strings on first non-whitespace */
   while (1)
   {
      while (isspace(*psz1))
         psz1++;
      while (isspace(*psz2))
         psz2++;
      if (toupper(*psz1) != toupper(*psz2) || *psz1 == '\0' || *psz2 == '\0')
         break;
      psz1++;
      psz2++;
   }
   return (*psz1 - *psz2);
}

/***************************************************************************
Map a parameter's string representation to something we can use. 
Returns False if the parameter string is not recognised, else TRUE.
***************************************************************************/
static int map_parameter(char *parmname)
{
   int iIndex;

   if (*parmname == '-')
     return(-1);

   for (iIndex = 0; parm_table[iIndex].label; iIndex++) 
      if (strwicmp(parm_table[iIndex].label, parmname) == 0)
         return(iIndex);

   rprintf(FERROR, "Unknown parameter encountered: \"%s\"\n", parmname);
   return(-1);
}


/***************************************************************************
Set a boolean variable from the text value stored in the passed string.
Returns True in success, False if the passed string does not correctly 
represent a boolean.
***************************************************************************/
static BOOL set_boolean(BOOL *pb, char *parmvalue)
{
   BOOL bRetval;

   bRetval = True;
   if (strwicmp(parmvalue, "yes") == 0 ||
       strwicmp(parmvalue, "true") == 0 ||
       strwicmp(parmvalue, "1") == 0)
      *pb = True;
   else
      if (strwicmp(parmvalue, "no") == 0 ||
          strwicmp(parmvalue, "False") == 0 ||
          strwicmp(parmvalue, "0") == 0)
         *pb = False;
      else
      {
         rprintf(FERROR, "Badly formed boolean in configuration file: \"%s\".\n",
               parmvalue);
         bRetval = False;
      }
   return (bRetval);
}

/***************************************************************************
Find a service by name. Otherwise works like get_service.
***************************************************************************/
static int getservicebyname(char *name, service *pserviceDest)
{
   int iService;

   for (iService = iNumServices - 1; iService >= 0; iService--)
      if (strwicmp(iSERVICE(iService).name, name) == 0) 
      {
         if (pserviceDest != NULL)
	   copy_service(pserviceDest, pSERVICE(iService));
         break;
      }

   return (iService);
}



/***************************************************************************
Copy a service structure to another

***************************************************************************/
static void copy_service(service *pserviceDest, 
                         service *pserviceSource)
{
  int i;

  for (i=0;parm_table[i].label;i++)
    if (parm_table[i].ptr && parm_table[i].class == P_LOCAL) {
	void *def_ptr = parm_table[i].ptr;
	void *src_ptr = 
	  ((char *)pserviceSource) + PTR_DIFF(def_ptr,&sDefault);
	void *dest_ptr = 
	  ((char *)pserviceDest) + PTR_DIFF(def_ptr,&sDefault);

	switch (parm_table[i].type)
	  {
	  case P_BOOL:
	  case P_BOOLREV:
	    *(BOOL *)dest_ptr = *(BOOL *)src_ptr;
	    break;

	  case P_INTEGER:
	  case P_ENUM:
	  case P_OCTAL:
	    *(int *)dest_ptr = *(int *)src_ptr;
	    break;

	  case P_CHAR:
	    *(char *)dest_ptr = *(char *)src_ptr;
	    break;

	  case P_STRING:
	    string_set(dest_ptr,*(char **)src_ptr);
	    break;

	  default:
	    break;
	  }
      }
}


/***************************************************************************
Process a parameter for a particular service number. If snum < 0
then assume we are in the globals
***************************************************************************/
static BOOL lp_do_parameter(int snum, char *parmname, char *parmvalue)
{
   int parmnum, i;
   void *parm_ptr=NULL; /* where we are going to store the result */
   void *def_ptr=NULL;

   parmnum = map_parameter(parmname);

   if (parmnum < 0)
     {
       rprintf(FERROR, "Ignoring unknown parameter \"%s\"\n", parmname);
       return(True);
     }

   def_ptr = parm_table[parmnum].ptr;

   /* we might point at a service, the default service or a global */
   if (snum < 0) {
     parm_ptr = def_ptr;
   } else {
       if (parm_table[parmnum].class == P_GLOBAL) {
	   rprintf(FERROR, "Global parameter %s found in service section!\n",parmname);
	   return(True);
	 }
       parm_ptr = ((char *)pSERVICE(snum)) + PTR_DIFF(def_ptr,&sDefault);
   }

   /* now switch on the type of variable it is */
   switch (parm_table[parmnum].type)
     {
     case P_BOOL:
       set_boolean(parm_ptr,parmvalue);
       break;

     case P_BOOLREV:
       set_boolean(parm_ptr,parmvalue);
       *(BOOL *)parm_ptr = ! *(BOOL *)parm_ptr;
       break;

     case P_INTEGER:
       *(int *)parm_ptr = atoi(parmvalue);
       break;

     case P_CHAR:
       *(char *)parm_ptr = *parmvalue;
       break;

     case P_OCTAL:
       sscanf(parmvalue,"%o",(int *)parm_ptr);
       break;

     case P_STRING:
       string_set(parm_ptr,parmvalue);
       break;

     case P_GSTRING:
       strcpy((char *)parm_ptr,parmvalue);
       break;

     case P_ENUM:
	     for (i=0;parm_table[parmnum].enum_list[i].name;i++) {
		     if (strequal(parmvalue, parm_table[parmnum].enum_list[i].name)) {
			     *(int *)parm_ptr = parm_table[parmnum].enum_list[i].value;
			     break;
		     }
	     }
	     break;
     case P_SEP:
	     break;
     }

   return(True);
}

/***************************************************************************
Process a parameter.
***************************************************************************/
static BOOL do_parameter(char *parmname, char *parmvalue)
{
   return lp_do_parameter(bInGlobalSection?-2:iServiceIndex, parmname, parmvalue);
}

/***************************************************************************
Process a new section (service). At this stage all sections are services.
Later we'll have special sections that permit server parameters to be set.
Returns True on success, False on failure.
***************************************************************************/
static BOOL do_section(char *sectionname)
{
   BOOL bRetval;
   BOOL isglobal = (strwicmp(sectionname, GLOBAL_NAME) == 0);
   bRetval = False;

   /* if we were in a global section then do the local inits */
   if (bInGlobalSection && !isglobal)
     init_locals();

   /* if we've just struck a global section, note the fact. */
   bInGlobalSection = isglobal;   

   /* check for multiple global sections */
   if (bInGlobalSection)
   {
     return(True);
   }

   /* if we have a current service, tidy it up before moving on */
   bRetval = True;

   if (iServiceIndex >= 0)
     bRetval = True;

   /* if all is still well, move to the next record in the services array */
   if (bRetval)
     {
       /* We put this here to avoid an odd message order if messages are */
       /* issued by the post-processing of a previous section. */

       if ((iServiceIndex=add_a_service(&sDefault,sectionname)) < 0)
	 {
	   rprintf(FERROR,"Failed to add a new service\n");
	   return(False);
	 }
     }

   return (bRetval);
}


/***************************************************************************
Load the services array from the services file. Return True on success, 
False on failure.
***************************************************************************/
BOOL lp_load(char *pszFname)
{
  pstring n2;
  BOOL bRetval;
 
  bRetval = False;

  bInGlobalSection = True;
  
  init_globals();

  pstrcpy(n2,pszFname);

  /* We get sections first, so have to start 'behind' to make up */
  iServiceIndex = -1;
  bRetval = pm_process(n2, do_section, do_parameter);
  
  bLoaded = True;

  return (bRetval);
}


/***************************************************************************
return the max number of services
***************************************************************************/
int lp_numservices(void)
{
  return(iNumServices);
}

/***************************************************************************
Return the number of the service with the given name, or -1 if it doesn't
exist. Note that this is a DIFFERENT ANIMAL from the internal function
getservicebyname()! This works ONLY if all services have been loaded, and
does not copy the found service.
***************************************************************************/
int lp_number(char *name)
{
   int iService;

   for (iService = iNumServices - 1; iService >= 0; iService--)
      if (strequal(lp_name(iService), name)) 
         break;

   return (iService);
}