#ifndef CONNECT___NCBI_UTIL__H
#define CONNECT___NCBI_UTIL__H

/* $Id: ncbi_util.h 603705 2020-03-16 14:16:39Z ivanov $
 * ===========================================================================
 *
 *                            PUBLIC DOMAIN NOTICE
 *               National Center for Biotechnology Information
 *
 *  This software/database is a "United States Government Work" under the
 *  terms of the United States Copyright Act.  It was written as part of
 *  the author's official duties as a United States Government employee and
 *  thus cannot be copyrighted.  This software/database is freely available
 *  to the public for use. The National Library of Medicine and the U.S.
 *  Government have not placed any restriction on its use or reproduction.
 *
 *  Although all reasonable efforts have been taken to ensure the accuracy
 *  and reliability of the software and data, the NLM and the U.S.
 *  Government do not and cannot warrant the performance or results that
 *  may be obtained by using this software or data. The NLM and the U.S.
 *  Government disclaim all warranties, express or implied, including
 *  warranties of performance, merchantability or fitness for any particular
 *  purpose.
 *
 *  Please cite the author in any work or product based on this material.
 *
 * ===========================================================================
 *
 * Authors:  Denis Vakatov, Anton Lavrentiev
 *
 * File Description:
 * @file ncbi_util.h
 *   Auxiliaries (mostly optional core to back and complement "ncbi_core.[ch]")
 * @sa
 *  ncbi_core.h
 *
 * 1. CORE support:
 *    macros:     LOG_WRITE(), LOG_DATA(),
 *                THIS_MODULE,  CORE_CURRENT_FUNCTION
 *    flags:      TLOG_FormatFlags, ELOG_FormatFlags
 *    methods:    LOG_ComposeMessage(), LOG_ToFILE(), NcbiMessagePlusError(),
 *                CORE_SetLOCK(), CORE_GetLOCK(),
 *                CORE_SetLOG(),  CORE_GetLOG(),
 *                CORE_SetLOGFILE[_Ex](), CORE_SetLOGFILE_NAME[_Ex]()
 *                LOG_ToFILE[_Ex]()
 *
 * 2. Auxiliary API:
 *       CORE_GetAppName()
 *       CORE_GetNcbiRequestID()
 *       CORE_GetPlatform()
 *       CORE_GetUsername[Ex]()
 *       CORE_GetVMPageSize()
 *       CORE_Msdelay()
 *
 * 3. Checksumming support:
 *       UTIL_CRC32_Update()
 *       UTIL_Adler32_Update()
 *
 * 4. Miscellaneous:
 *       UTIL_MatchesMask[Ex]()
 *       UTIL_NcbiLocalHostName()
 *       UTIL_PrintableString[Size]()
 *
 * 5. Internal MSWIN support for Unicode (mostly in error messages)
 *
 */

#include <connect/ncbi_core.h>
#include <stdio.h>


/** @addtogroup UtilityFunc
 *
 * @{
 */


#ifdef __cplusplus
extern "C" {
#endif


/******************************************************************************
 *  MT locking
 */

/** Set the MT critical section lock/unlock handler -- to be used by the core
 * internals for protection of internal static variables and other MT-sensitive
 * code from being accessed/changed by several threads simultaneously. It is
 * also to fully protect the core log handler and core regirsty, including
 * their setup, as well as callback and cleanup functions.
 * @warning This function itself is NOT MT-safe!
 * @warning If there is an active CORE MT-lock set already, which is different
 *          from the new one, then MT_LOCK_Delete() is called for the old lock
 *          (i.e. the one being replaced).
 * @note The following are the minimal requirements for the lock that is to be
 * used as a CORE MT_LOCK in the CONNECT library:
 * - if locking for read is available, then the lock must allow one nested lock
 * for read when it has been already locked for write (naturally, by the same
 * thread);
 * - if locking for read is not available (i.e. the read lock is implemented as
 * a (write) lock), the lock must allow recursive locking (by the same thread)
 * to the depth of 2.
 * @param lk
 *  MT-Lock as created by MT_LOCK_Create
 * @sa
 *  MT_LOCK_Create, MT_LOCK_Delete, CORE_SetLOG, CORE_SetREG
 */
extern NCBI_XCONNECT_EXPORT void    CORE_SetLOCK(MT_LOCK lk);


/** Get the lock handle that is to be used by the core internals.
 * @return
 *  MT_LOCK handle of an active lock, or NULL if no lock is currently set
 * @warning
 *  You may not delete the handle with MT_LOCK_Delete();  use CORE_SetLOCK(0)
 *  instead (or replace it with a different MT_LOCK).
 * @note
 *  CONNECT may provide a default lock implementation on most platforms, so the
 *  returned lock may be non-NULL even without a prior call to CORE_SetLOCK().
 * @sa
 *  CORE_SetLOCK
 */
extern NCBI_XCONNECT_EXPORT MT_LOCK CORE_GetLOCK(void);



/******************************************************************************
 *  Error handling and logging
 */

/** Auxiliary plain macros to write message (maybe, with raw data) to the log.
 * @sa
 *  LOG_Write
 */
#define  LOG_WRITE(lg, code, subcode, level, message)                        \
    LOG_Write(lg, code, subcode, level, THIS_MODULE, CORE_CURRENT_FUNCTION,  \
              __FILE__, __LINE__, message, 0, 0)

#ifdef   LOG_DATA
/* AIX's <pthread.h> defines LOG_DATA to be an integer constant;
   we must explicitly drop such definitions to avoid trouble */
#  undef LOG_DATA
#endif
#define  LOG_DATA(lg, code, subcode, level, data, size, message)             \
    LOG_Write(lg, code, subcode, level, THIS_MODULE, CORE_CURRENT_FUNCTION,  \
              __FILE__, __LINE__, message, data, size)


/** Default for THIS_MODULE.
 */
#ifndef   THIS_MODULE
#  define THIS_MODULE  0
#endif


/** Get current function name.
 * @note Defined inside of either a method or a function body only.
 * See <corelib/ncbidiag.hpp> for definition of NCBI_CURRENT_FUNCTION.
 * @sa
 *  NCBI_CURRENT_FUNCTION
 */
#if    defined(__GNUC__)                                       ||     \
      (defined(__MWERKS__)        &&  (__MWERKS__ >= 0x3000))  ||     \
      (defined(__ICC)             &&  (__ICC >= 600))
#  define CORE_CURRENT_FUNCTION  __PRETTY_FUNCTION__
#elif defined(__FUNCSIG__)
#  define CORE_CURRENT_FUNCTION  __FUNCSIG__
#elif (defined(__INTEL_COMPILER)  &&  (__INTEL_COMPILER >= 600))  ||  \
      (defined(__IBMCPP__)        &&  (__IBMCPP__ >= 500))
#  define CORE_CURRENT_FUNCTION  __FUNCTION__
#elif  defined(__BORLANDC__)      &&  (__BORLANDC__ >= 0x550)
#  define CORE_CURRENT_FUNCTION  __FUNC__
#elif  defined(__STDC_VERSION__)  &&  (__STDC_VERSION__ >= 199901)
#  define CORE_CURRENT_FUNCTION  __func__
#else
#  define CORE_CURRENT_FUNCTION  0
#endif


/** Set the log handle (no logging if "lg" is passed zero) -- to be used by
 * the core internals.
 * If there is an active log handler set already, and it is different from the
 * new one, then LOG_Delete is called internally for the old logger (that is,
 * the one being replaced).
 * @param lg
 *  LOG handle as returned by LOG_Create, or NULL to stop logging
 * @sa
 *  LOG_Create, LOG_Delete, CORE_GetLOG, CORE_SetLOCK
 */
extern NCBI_XCONNECT_EXPORT void CORE_SetLOG(LOG lg);


/** Get the log handle that is to be used by the core internals.
 * @return
 *  LOG handle as previously set by CORE_SetLOG() or NULL if no logging is
 *  currently active
 * @warning
 *  You may not delete the handle by means of LOG_Delete();  use CORE_SetLOG(0)
 *  instead (or replace it with a different LOG).
 * @sa
 *  CORE_SetLOG
 */
extern NCBI_XCONNECT_EXPORT LOG  CORE_GetLOG(void);


/** Standard logging to the specified file stream.
 * @param fp
 *  The file stream to log to
 * @param cut_off
 *  Do not post messages with severity levels lower than specified
 * @param fatal_err
 *  Severity greater than or equal to the specified level always posts to log,
 *  and then aborts the application
 * @param auto_close
 *  Do "fclose(fp)" when the LOG is reset/destroyed
 * @sa
 *  LOG_ToFILE_Ex, CORE_SetLOG
 */
extern NCBI_XCONNECT_EXPORT void CORE_SetLOGFILE_Ex
(FILE*       fp,
 ELOG_Level  cut_off,
 ELOG_Level  fatal_err,
 int/*bool*/ auto_close
 );


/** Same as CORE_SetLOGFILE_Ex(fp, eLOG_Trace, eLOG_Fatal, auto_close).
 * @sa
 *  CORE_SetLOGFILE_Ex, CORE_SetLOG
 */
extern NCBI_XCONNECT_EXPORT void CORE_SetLOGFILE
(FILE*       fp,
 int/*bool*/ auto_close
 );


/** Same as CORE_SetLOGFILE_Ex(fopen(logfile, "a"), cut_off, fatal_err, TRUE).
 * @param logile
 *  Filename to write the log into
 * @param cut_off
 *  Do not post messages with severity levels lower than specified
 * @param fatal_err
 *  Severity greater than or equal to the specified level always posts to log,
 *  and then aborts the application
 * @return
 *  Return zero on error, non-zero on success
 * @sa
 *  CORE_SetLOGFILE_Ex, CORE_SetLOG
 */
extern NCBI_XCONNECT_EXPORT int/*bool*/ CORE_SetLOGFILE_NAME_Ex
(const char* logfile,
 ELOG_Level  cut_off,
 ELOG_Level  fatal_err
 );


/** Same as CORE_SetLOGFILE_NAME_Ex(logfile, eLOG_Trace, eLOG_Fatal).
 * @sa
 *  CORE_SetLOGFILE_NAME_Ex, CORE_SetLOG
 */
extern NCBI_XCONNECT_EXPORT int/*bool*/ CORE_SetLOGFILE_NAME
(const char* logfile
);


/** LOG formatting flags:  what parts of the message to actually appear.
 * @sa
 *   CORE_SetLOGFormatFlags
 */
enum ELOG_FormatFlag {
    fLOG_Default       = 0x0,    /**< fLOG_Short if NDEBUG, else fLOG_Full   */
    fLOG_Level         = 0x1,
    fLOG_Module        = 0x2,
    fLOG_FileLine      = 0x4,
    fLOG_DateTime      = 0x8,
    fLOG_Function      = 0x10,
    fLOG_FullOctal     = 0x2000, /**< do not do reduction in octal data bytes*/
    fLOG_OmitNoteLevel = 0x4000, /**< do not add "NOTE" if level is eLOG_Note*/
    fLOG_None          = 0x8000  /**< nothing but spec'd parts, msg and data */
};
typedef unsigned int TLOG_FormatFlags;  /**< bitwise OR of "ELOG_FormatFlag" */
#define fLOG_Short   fLOG_Level
#define fLOG_Full   (fLOG_Level | fLOG_Module | fLOG_FileLine)

extern NCBI_XCONNECT_EXPORT TLOG_FormatFlags CORE_SetLOGFormatFlags
(TLOG_FormatFlags
);


/** Compose a message using the "call_data" info.
 * Full log record format:
 *     mm/dd/yy HH:MM:SS "<file>", line <line>: [<module>::<function>] <level>: <message>
 *     \n----- [BEGIN] Raw Data (<raw_size> bytes) -----\n
 *     <raw_data>
 *     \n----- [END] Raw Data -----\n
 *
 * @note
 *  The returned string must be deallocated using "free()".
 * @param mess
 *  Broken down message
 * @param flags
 *  Which fields of "mess" to use
 * @sa
 *  CORE_SetLOG, CORE_SetLOGFormatFlags
 */
extern NCBI_XCONNECT_EXPORT char* LOG_ComposeMessage
(const SLOG_Message* mess,
 TLOG_FormatFlags    flags
 );


/** LOG_Reset specialized to log to a "FILE*" stream using LOG_ComposeMessage.
 * @param lg
 *  Created by LOG_Create
 * @param fp
 *  The file stream to log to
 * @param cut_off
 *  Do not post messages with severity levels lower than specified
 * @param fatal_err
 *  Severity greater or equal to "fatal_err" always logs and aborts the program
 * @param auto_close
 *  Whether to do "fclose(fp)" when the LOG is reset/destroyed
 * @sa
 *  LOG_Create, LOG_Reset, LOG_ComposeMessage, LOG_ToFILE
 */
extern NCBI_XCONNECT_EXPORT void LOG_ToFILE_Ex
(LOG         lg,
 FILE*       fp,
 ELOG_Level  cut_off,
 ELOG_Level  fatal_err,
 int/*bool*/ auto_close
 );


/** Same as LOG_ToFILEx(lg, fp, eLOG_Trace, eLOG_Fatal, auto_close).
 * @sa
 *  LOG_ToFILE_Ex
 */
extern NCBI_XCONNECT_EXPORT void LOG_ToFILE
(LOG         lg,
 FILE*       fp,
 int/*bool*/ auto_close
 );


/** Add current "error" (and maybe its description) to the message:
 * <message>[ {error=[[<error>][,]][<descr>]}]
 * @param dynamic
 *  [inout] non-zero pointed value means message was allocated from heap
 * @param message
 *  [in]    message text (can be NULL)
 * @param error
 *  [in]    error code (if it is zero, then use "descr" only if non-NULL/empty)
 * @param descr
 *  [in]    error description (if NULL, then use "strerror(error)" if error!=0)
 * @return
 *  Always non-NULL message (perhaps, "") and re-set "*dynamic" as appropriate.
 * @warning
 *  This routine may call "free(message)" if it had to reallocate the original
 *  message that had been allocated dynamically before the call (and "*dynamic"
 *  thus had been passed non-zero).
 * @sa
 *  LOG_ComposeMessage
 */
extern NCBI_XCONNECT_EXPORT const char* NcbiMessagePlusError
(int/*bool*/ *dynamic,
 const char*  message,
 int          error,
 const char*  descr
 );



/******************************************************************************
 *  Registry
 */

/** Set the registry (no registry if "rg" is passed zero) -- to be used by
 * the core internals.
 * If there is an active registry set already, and it is different from the new
 * one, then REG_Delete() is called for the old(replaced) registry.
 * @param rg
 *  Registry handle as returned by REG_Create()
 * @sa
 *  REG_Create, REG_Delete, CORE_GetREG, CORE_SetLOCK
 */
extern NCBI_XCONNECT_EXPORT void CORE_SetREG(REG rg);


/** Get the registry that is to be used by the core internals.
 * @return
 *  Registry handle as previously set by CORE_SetREG() or NULL if none
 * @warning
 *  You may not delete the handle with REG_Delete();  use CORE_SetREG(0)
 *  instead (or replace it with a different REG).
 * @sa
 *  CORE_SetREG
 */
extern NCBI_XCONNECT_EXPORT REG  CORE_GetREG(void);


/******************************************************************************
 *  Auxiliary API
 */

/** Obtain current application name (toolkit dependent).
 * @return
 *  Return an empty string ("") when the application name cannot be determined;
 *  otherwise, return a '\0'-terminated string
 *
 * NOTE that setting an application name concurrently with this
 * call can cause undefined behavior or a stale pointer returned.
 */
extern NCBI_XCONNECT_EXPORT const char* CORE_GetAppName(void);


/** NCBI request ID enumerator */
typedef enum {
    eNcbiRequestID_None = 0,
    eNcbiRequestID_HitID,     /**< NCBI Hit     ID */
    eNcbiRequestID_SID        /**< NCBI Session ID */
} ENcbiRequestID;


/** NCBI request "DTab-Local" header  */
extern NCBI_XCONNECT_EXPORT char* CORE_GetNcbiRequestDtab;


/** Obtain current NCBI request ID (if known, per thread).
 * @return
 *  Return NULL when the ID cannot be determined or an error has occurred;
 *  otherwise, return a '\0'-terminated, non-empty string that is allocated
 *  on the heap, and must be free()'d when no longer needed.
 */
extern NCBI_XCONNECT_EXPORT char* CORE_GetNcbiRequestID
(ENcbiRequestID reqid);


/** Return NCBI platrofm ID (if known).
 * @return
 *  Return read-only textual but machine-readable platform description.
 */
extern NCBI_XCONNECT_EXPORT const char* CORE_GetPlatform(void);


/** Select which username is the most preferable to obtain from the system. */
typedef enum {
    eCORE_UsernameCurrent,  /**< process UID */
    eCORE_UsernameLogin,    /**< login UID   */
    eCORE_UsernameReal      /**< real UID    */
} ECORE_Username;


/** Obtain and store in the buffer provided, the best (as possible) user name
 * that matches the requested username selector.
 * Both "buf" and "bufsize" must not be zeros.
 * @param buf
 *  Pointer to buffer to store the user name at
 * @param bufsize
 *  Size of buffer in bytes
 * @param username
 *  Selects which username to get (most preferably)
 * @return
 *  Return NULL when the user name cannot be stored (e.g. buffer too small);
 *  otherwise, return "buf".  Return "buf" as an empty string "" if the user
 *  name cannot be determined.
 * @note
 *  For some OSes the username selector may not effect any differences,
 *  and for some OS releases, it may cause different results.
 * @sa
 *  CORE_GetUsername, ECORE_Username
 */
extern NCBI_XCONNECT_EXPORT const char* CORE_GetUsernameEx
(char*          buf,
 size_t         bufsize,
 ECORE_Username username
 );


/** Equivalent to CORE_GetUsernameEx(buf, bufsize, eNCBI_UsernameLogin)
 * except that it always returns non-empty "buf" when successful, or NULL
 * otherwise (i.e. when the username cannot be either obtained or stored).
 * @sa
 *  CORE_GetUsernameEx, ECORE_Username
 */
extern NCBI_XCONNECT_EXPORT const char* CORE_GetUsername
(char*  buf,
 size_t bufsize
 );


/** Obtain virtual memory page size.
 * @return
 *  0 if the page size cannot be determined.
 */
extern NCBI_XCONNECT_EXPORT size_t CORE_GetVMPageSize(void);


/** Delay execution of the current thread by the specified number of
 *  milliseconds
 * @return
 *  0 if the page size cannot be determined.
 */
extern NCBI_XCONNECT_EXPORT void CORE_Msdelay(unsigned long ms);



/******************************************************************************
 *  Checksumming
 */

/** Calculate/Update CRC-32 checksum
 * NB:  Initial checksum is "0".
 * @param checksum
 *  Checksum to update (start with 0)
 * @param ptr
 *  Block of data
 * @param len
 *  Size of block of data
 * @return
 *  Return the checksum updated according to the contents of the block
 *  pointed to by "ptr" and having "len" bytes in it.
 */
extern NCBI_XCONNECT_EXPORT unsigned int UTIL_CRC32_Update
(unsigned int checksum,
 const void*  ptr,
 size_t       len
 );


/** Calculate/Update Adler-32 checksum
 * NB:  Initial checksum is "1".
 * @param checksum
 *  Checksum to update (start with 1)
 * @param ptr
 *  Block of data
 * @param len
 *  Size of block of data
 * @return
 *  Return the checksum updated according to the contents of the block
 *  pointed to by "ptr" and having "len" bytes in it.
 */
extern NCBI_XCONNECT_EXPORT unsigned int UTIL_Adler32_Update
(unsigned int checksum,
 const void*  ptr,
 size_t       len
 );


/** Cryptographic hash function descriptor:
 * @var block_len
 *  Byte length of hashing blocks (e.g. 64 bytes for MD5, SHA1, SHA256)
 * @var digest_len
 *  Byte length of the resultant digest (e.g. MD5: 16, SHA1: 20, SHA256: 32)
 * @var init
 *  Init and set a hash context; return 0 on failure, non-zero on success
 * @var update
 *  Update the hash with data provided
 * @var fini
 *  Write out the resultant digest (if non-0) and destroy the context
 * @sa
 *  UTIL_GenerateHMAC
 */
typedef struct {
    size_t block_len;
    size_t digest_len;

    int/*bool*/ (*init)  (void** ctx);
    void        (*update)(void*  ctx, const void* data, size_t data_len);
    void        (*fini)  (void*  ctx, void* digest);
} SHASH_Descriptor;


/** Generate an RFC2401 digest (HMAC).
 * @param hash
 *  Hash function descriptor
 * @param text
 *  Text to get a digest for
 * @param text_key
 *  Byte length of the text
 * @param key
 *  Key to hash the text with
 * @param key_len
 *  Byte length of the key (recommended to be no less than "hash::digest_len")
 * @param digest
 *  The resultant HMAC storage (must be of an adequate size)
 * @return
 *  NULL on errors ("digest" will not be valid), or "digest" on success.
 * @sa
 *  SHASH_Descriptor
 */
extern NCBI_XCONNECT_EXPORT void* UTIL_GenerateHMAC
(const SHASH_Descriptor* hash,
 const void*             text,
 size_t                  text_len,
 const void*             key,
 size_t                  key_len,
 void*                   digest);



/******************************************************************************
 *  Miscellanea
 */


/** Match a given text with a given pattern mask.  Very similar to fnmatch(3),
 *  but there are differences (see also glob(7)).  There's no special treatment
 *  for a slash character '/' in this call.
 * @param text
 *  A text to match
 * @param mask
 *  A text pattern, which, along with ordinary characters that must match
 *  literally in the given "text", can contain:  '*' to denote any sequence of
 *  characters (including none), '?' to denote any single character, and
 *  character classes in the forms of "[...]" or "[!...]" that must MATCH
 *  or NOT MATCH, respectively, a single character in "text".  To cancel the
 *  special meaning of '*', '?' or '[', they can be prepended with a backslash
 *  '\\' (the backslash in front of other characters does not change their
 *  meaning, so "\\\\" matches one graphical backslash in the "text").  Within
 *  a character class, to have its literal meaning a closing square bracket ']'
 *  must be used at the first position, whereas '?', '*', '[, and '\\' stand
 *  just for themselves.  Two characters separated by a minus sign '-' denote
 *  a range that can be used for contraction to include all characters in
 *  between:  "[A-F]" is equivalent to "[ABCDEF]".  For its literal meaning,
 *  the minus sign '-' can be used either at the very first position, or the
 *  last position before the closing bracket ']'.  To have a range that begins
 *  with an exclamation point, one has to use a dummy empty range followed
 *  by that range with '!'.
 *  Examples:
 *  "!"        matches a single '!' (note that just "[!]" is invalid);
 *  "[!!]"     matches any character, which is not an exclamation point '!';
 *  "[][!]"    matches ']', '[', and '!';
 *  "[!][-]"   matches any character except for ']', '[', and '-';
 *  "[-]"      matches a minus sign '-' (same as '-' just by itself);
 *  "[?*\\]"   matches either '?', or '*', or a backslash '\\';
 *  "[]-\\]"   matches nothing as it defines an empty range (from ']' to '\\');
 *  "\\[a]\\*" matches a literal substring "[a]*";
 *  "[![a-]"   matches any char but '[', 'a' or '-' (same as "[!-[a]"; but not
 *             "[![-a]", which defines an empty range, thus matches any char!);
 *  "[]A]"     matches either ']' or 'A' (NB: "[A]]" matches a substring "A]");
 *  "[0-9-]"   matches any decimal digit or a minus sign '-' (same: "[-0-9]");
 *  "[9-0!-$]" matches '!', '"', '#', and '$' (as first range matches nothing).
 * @note
 *  In the above, each double backslash denotes a single graphical backslash
 *  character (C string notation is used).
 * @note
 *  Unlike shell globbing, "[--0]" *does* match the slash character '/' (along
 *  with '-', '.', and '0' that all fall within the range).
 * @param ignore_case
 *  Whether to ignore the case of the letters (a-z) in comparisons
 * @return
 *  Non-zero if "text" matches "mask";  otherwise (including pattern errors),
 *  return zero
 * @sa
 *  UTIL_MatchesMask
 */
extern NCBI_XCONNECT_EXPORT int/*bool*/ UTIL_MatchesMaskEx
(const char* text,
 const char* mask,
 int/*bool*/ ignore_case
);

/** Shortcut for UTIL_MatchesMaskEx(text, mask, 1), that is matching is done
 *  case-insensitively for the letters (a-z).
 * @sa
 *  UTIL_MatchesMaskEx
 */
extern NCBI_XCONNECT_EXPORT int/*bool*/ UTIL_MatchesMask
(const char* text,
 const char* mask
);


/** Cut off well-known NCBI domain suffix out of the passed "hostname".
 * @param hostname
 *  Hostname to shorten (if possible)
 * @return
 *  NULL if the hostname wasn't modified;  otherwise, return "hostname"
 */
extern NCBI_XCONNECT_EXPORT char* UTIL_NcbiLocalHostName
(char* hostname
 );


/** Calculate size of buffer needed to store printable representation of the
 *  block of data of the specified size (or, if size is 0, strlen(data))
 *  (without the '\0' terminator).
 * @note
 *  The calculated size does not account for a terminating '\0'.
 * @param data
 *  Block of data (NULL causes 0 to return regardless of "size")
 * @param size
 *  Size of the block (0 causes strlen(data) to be used)
 * @return
 *  The buffer size needed (0 for NULL or empty data)
 * @sa
 *  UTIL_PrintableString
 */
extern NCBI_XCONNECT_EXPORT size_t UTIL_PrintableStringSize
(const char* data,
 size_t      size
 );


typedef enum {
    eUTIL_PrintableFullOctal = 1,  /**< No contactions in octals \ooo        */
    eUTIL_PrintableNoNewLine = 2   /**< Do not include graphical newlines    */
} EUTIL_PrintableFlags;
typedef int TUTIL_PrintableFlags;  /**< Bitwise "OR" of EUTIL_PrintableFlags */


/** Create printable representation of the block of data of the specified size
 *  (or, if size is 0, strlen(data)), and return the buffer pointer past the
 *  last stored character (non '\0'-terminated).  Non-printable characters can
 *  be represented in a reduced octal form as long as the result is unambiguous
 *  (unless "full" passed true (non-zero), in which case all non-printable
 *  characters get represented by full octal tetrads).  NB: Hexadecimal output
 *  is not used because it is ambiguous by the standard (can contain undefined
 *  number of hex digits).
 * @note
 *  The input buffer "buf" where to store the printable representation is
 *  assumed to be of adequate size to hold the resultant string (use
 *  UTIL_PrintableStringSize() to obtain the size prior to this call).
 * @param data
 *  Block of data (NULL causes NULL to return regardless of "size" or "buf")
 * @param size
 *  Size of block (0 causes strlen(data) to be used)
 * @param buf
 *  Buffer to store the result (NULL always causes NULL to return)
 * @param flags
 *  How to print representations of certain non-printable characters
 * @return
 *  Next position in the buffer past the last stored character
 * @warning
 *  The call *does not* '\0'-terminate its output!
 * @sa
 *  UTIL_PrintableStringSize, EUTIL_PrintableFlags
 */
extern NCBI_XCONNECT_EXPORT char* UTIL_PrintableString
(const char*          data,
 size_t               size,
 char*                buf,
 TUTIL_PrintableFlags flags
 );


/** Conversion from Unicode to UTF8, and back.  MSWIN-specific and internal.
 *
 * @note  UTIL_ReleaseBufferOnHeap() must be used to free the buffers returned
 *        from UTIL_TcharToUtf8OnHeap(),  and UTIL_ReleaseBuffer() to free the
 *        ones returned from UTIL_TcharToUtf8()/UTIL_Utf8ToTchar().
 *
 * @note  If you change these macros (here and in #else) you need to make
 *        similar changes in ncbi_strerror.c as well.
 */
#if defined(NCBI_OS_MSWIN)  &&  defined(_UNICODE)
extern const char*    UTIL_TcharToUtf8OnHeap(const wchar_t* str);
extern const char*    UTIL_TcharToUtf8      (const wchar_t* str);
extern const wchar_t* UTIL_Utf8ToTchar      (const    char* str);
#  define             UTIL_ReleaseBuffer(x)        UTIL_ReleaseBufferOnHeap(x)
#else
#  define             UTIL_TcharToUtf8OnHeap(x)    (x)
#  define             UTIL_TcharToUtf8(x)          (x)
#  define             UTIL_Utf8ToTchar(x)          (x)
#  define             UTIL_ReleaseBuffer(x)        /*void*/
#endif /*NCBI_OS_MSWIN && _UNICODE*/

#ifdef NCBI_OS_MSWIN
extern void           UTIL_ReleaseBufferOnHeap(const void* ptr);
#else
#  define             UTIL_ReleaseBufferOnHeap(x)  /*void*/
#endif /*NCBI_OS_MSWIN*/


#ifdef __cplusplus
}  /* extern "C" */
#endif


/* @} */

#endif /* CONNECT___NCBI_UTIL__H */
