/*
* $Id: readtags.h 443 2006-05-30 04:37:13Z darren $
*
* Copyright (c) 1996-2003, Darren Hiebert
*
* This source code is released for the public domain.
*
* This file defines the public interface for looking up tag entries in tag
* files.
*
* The functions defined in this interface are intended to provide tag file
* support to a software tool. The tag lookups provided are sufficiently fast
* enough to permit opening a sorted tag file, searching for a matching tag,
* then closing the tag file each time a tag is looked up (search times are
* on the order of hundreths of a second, even for huge tag files). This is
* the recommended use of this library for most tool applications. Adhering
* to this approach permits a user to regenerate a tag file at will without
* the tool needing to detect and resynchronize with changes to the tag file.
* Even for an unsorted 24MB tag file, tag searches take about one second.
*/
#ifndef READTAGS_H
#define READTAGS_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* MACROS
*/
/* Options for tagsSetSortType() */
typedef enum {
TAG_UNSORTED, TAG_SORTED, TAG_FOLDSORTED
} sortType ;
/* Options for tagsFind() */
#define TAG_FULLMATCH 0x0
#define TAG_PARTIALMATCH 0x1
#define TAG_OBSERVECASE 0x0
#define TAG_IGNORECASE 0x2
/*
* DATA DECLARATIONS
*/
typedef enum { TagFailure = 0, TagSuccess = 1 } tagResult;
struct sTagFile;
typedef struct sTagFile tagFile;
/* This structure contains information about the tag file. */
typedef struct {
struct {
/* was the tag file successfully opened? */
int opened;
/* errno value when 'opened' is false */
int error_number;
} status;
/* information about the structure of the tag file */
struct {
/* format of tag file (1 = original, 2 = extended) */
short format;
/* how is the tag file sorted? */
sortType sort;
} file;
/* information about the program which created this tag file */
struct {
/* name of author of generating program (may be null) */
const char *author;
/* name of program (may be null) */
const char *name;
/* URL of distribution (may be null) */
const char *url;
/* program version (may be null) */
const char *version;
} program;
} tagFileInfo;
/* This structure contains information about an extension field for a tag.
* These exist at the end of the tag in the form "key:value").
*/
typedef struct {
/* the key of the extension field */
const char *key;
/* the value of the extension field (may be an empty string) */
const char *value;
} tagExtensionField;
/* This structure contains information about a specific tag. */
typedef struct {
/* name of tag */
const char *name;
/* path of source file containing definition of tag */
const char *file;
/* address for locating tag in source file */
struct {
/* pattern for locating source line
* (may be NULL if not present) */
const char *pattern;
/* line number in source file of tag definition
* (may be zero if not known) */
unsigned long lineNumber;
} address;
/* kind of tag (may by name, character, or NULL if not known) */
const char *kind;
/* is tag of file-limited scope? */
short fileScope;
/* miscellaneous extension fields */
struct {
/* number of entries in `list' */
unsigned short count;
/* list of key value pairs */
tagExtensionField *list;
} fields;
} tagEntry;
/*
* FUNCTION PROTOTYPES
*/
/*
* This function must be called before calling other functions in this
* library. It is passed the path to the tag file to read and a (possibly
* null) pointer to a structure which, if not null, will be populated with
* information about the tag file. If successful, the function will return a
* handle which must be supplied to other calls to read information from the
* tag file, and info.status.opened will be set to true. If unsuccessful,
* info.status.opened will be set to false and info.status.error_number will
* be set to the errno value representing the system error preventing the tag
* file from being successfully opened.
*/
extern tagFile *tagsOpen (const char *const filePath, tagFileInfo *const info);
/*
* This function allows the client to override the normal automatic detection
* of how a tag file is sorted. Permissible values for `type' are
* TAG_UNSORTED, TAG_SORTED, TAG_FOLDSORTED. Tag files in the new extended
* format contain a key indicating whether or not they are sorted. However,
* tag files in the original format do not contain such a key even when
* sorted, preventing this library from taking advantage of fast binary
* lookups. If the client knows that such an unmarked tag file is indeed
* sorted (or not), it can override the automatic detection. Note that
* incorrect lookup results will result if a tag file is marked as sorted when
* it actually is not. The function will return TagSuccess if called on an
* open tag file or TagFailure if not.
*/
extern tagResult tagsSetSortType (tagFile *const file, const sortType type);
/*
* Reads the first tag in the file, if any. It is passed the handle to an
* opened tag file and a (possibly null) pointer to a structure which, if not
* null, will be populated with information about the first tag file entry.
* The function will return TagSuccess another tag entry is found, or
* TagFailure if not (i.e. it reached end of file).
*/
extern tagResult tagsFirst (tagFile *const file, tagEntry *const entry);
/*
* Step to the next tag in the file, if any. It is passed the handle to an
* opened tag file and a (possibly null) pointer to a structure which, if not
* null, will be populated with information about the next tag file entry. The
* function will return TagSuccess another tag entry is found, or TagFailure
* if not (i.e. it reached end of file). It will always read the first tag in
* the file immediately after calling tagsOpen().
*/
extern tagResult tagsNext (tagFile *const file, tagEntry *const entry);
/*
* Retrieve the value associated with the extension field for a specified key.
* It is passed a pointer to a structure already populated with values by a
* previous call to tagsNext(), tagsFind(), or tagsFindNext(), and a string
* containing the key of the desired extension field. If no such field of the
* specified key exists, the function will return null.
*/
extern const char *tagsField (const tagEntry *const entry, const char *const key);
/*
* Find the first tag matching `name'. The structure pointed to by `entry'
* will be populated with information about the tag file entry. If a tag file
* is sorted using the C locale, a binary search algorithm is used to search
* the tag file, resulting in very fast tag lookups, even in huge tag files.
* Various options controlling the matches can be combined by bit-wise or-ing
* certain values together. The available values are:
*
* TAG_PARTIALMATCH
* Tags whose leading characters match `name' will qualify.
*
* TAG_FULLMATCH
* Only tags whose full lengths match `name' will qualify.
*
* TAG_IGNORECASE
* Matching will be performed in a case-insenstive manner. Note that
* this disables binary searches of the tag file.
*
* TAG_OBSERVECASE
* Matching will be performed in a case-senstive manner. Note that
* this enables binary searches of the tag file.
*
* The function will return TagSuccess if a tag matching the name is found, or
* TagFailure if not.
*/
extern tagResult tagsFind (tagFile *const file, tagEntry *const entry, const char *const name, const int options);
/*
* Find the next tag matching the name and options supplied to the most recent
* call to tagsFind() for the same tag file. The structure pointed to by
* `entry' will be populated with information about the tag file entry. The
* function will return TagSuccess if another tag matching the name is found,
* or TagFailure if not.
*/
extern tagResult tagsFindNext (tagFile *const file, tagEntry *const entry);
/*
* Call tagsTerminate() at completion of reading the tag file, which will
* close the file and free any internal memory allocated. The function will
* return TagFailure is no file is currently open, TagSuccess otherwise.
*/
extern tagResult tagsClose (tagFile *const file);
#ifdef __cplusplus
};
#endif
#endif
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