tor-android/external/badvpn_dns/ncd/NCDPlaceholderDb.h

96 lines
3.9 KiB
C

/**
* @file NCDPlaceholderDb.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef BADVPN_NCDPLACEHOLDERDB_H
#define BADVPN_NCDPLACEHOLDERDB_H
#include <stddef.h>
#include <misc/debug.h>
#include <ncd/NCDStringIndex.h>
struct NCDPlaceholderDb__entry {
NCD_string_id_t *varnames;
size_t num_names;
};
/**
* Associates variable placeholder numbers to variable names.
* This is populated by {@link NCDInterpProcess_Init} when converting the {@link NCDValue}
* objects in the AST to compact representations in {@link NCDValMem}. Variables are
* replaced with placeholder identifiers (integers), which this object associates
* with their names.
* During interpretation, when a statement is being initialized, the compact form held
* by {@link NCDInterpProcess} is byte-copied, and placeholders are replaced with the
* values of corresponding variables using {@link NCDVal_ReplacePlaceholders}.
*/
typedef struct {
struct NCDPlaceholderDb__entry *arr;
size_t count;
size_t capacity;
NCDStringIndex *string_index;
} NCDPlaceholderDb;
/**
* Initializes the placeholder database.
* Returns 1 on success, and 0 on failure.
*/
int NCDPlaceholderDb_Init (NCDPlaceholderDb *o, NCDStringIndex *string_index) WARN_UNUSED;
/**
* Frees the placeholder database.
*/
void NCDPlaceholderDb_Free (NCDPlaceholderDb *o);
/**
* Adds a variable to the database.
*
* @param varname name of the variable (text, including dots). Must not be NULL.
* @param out_plid on success, the placeholder identifier will be returned here. Must
* not be NULL.
* @return 1 on success, 0 on failure
*/
int NCDPlaceholderDb_AddVariable (NCDPlaceholderDb *o, const char *varname, int *out_plid) WARN_UNUSED;
/**
* Retrieves the name of the variable associated with a placeholder identifier.
*
* @param plid placeholder identifier; must have been previously provided by
* {@link NCDPlaceholderDb_AddVariable}.
* @return name of the variable, split by dots. The returned value points to
* an array of pointers to strings, which is terminated by a NULL
* pointer. These all point to internal data in the placeholder
* database; they must not be modified, and remain valid until the
* database is freed.
* Note that there will always be at least one string in the result.
*/
void NCDPlaceholderDb_GetVariable (NCDPlaceholderDb *o, int plid, const NCD_string_id_t **out_varnames, size_t *out_num_names);
#endif