icuSources/common/unicode/utrace.h

   1 /*
   2 *******************************************************************************
   3 *
   4 *   Copyright (C) 2003-2004, International Business Machines
   5 *   Corporation and others.  All Rights Reserved.
   6 *
   7 *******************************************************************************
   8 *   file name:  utrace.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 2003aug06
  14 *   created by: Markus W. Scherer
  15 *
  16 *   Definitions for ICU tracing/logging.
  17 *
  18 */
  19
  20 #ifndef __UTRACE_H__
  21 #define __UTRACE_H__
  22
  23 #include <stdarg.h>
  24 #include "unicode/utypes.h"
  25
  26 U_CDECL_BEGIN
  27
  28 #ifndef U_HIDE_DRAFT_API
  29
  30 /**
  31  * Trace severity levels.  Higher levels increase the verbosity of the trace output.
  32  * @see utrace_setLevel
  33  * @draft ICU 2.8
  34  */
  35 typedef enum UTraceLevel {
  36     /** Disable all tracing  @draft ICU 2.8*/
  37     UTRACE_OFF=-1,
  38     /** Trace error conditions only  @draft ICU 2.8*/
  39     UTRACE_ERROR=0,
  40     /** Trace errors and warnings  @draft ICU 2.8*/
  41     UTRACE_WARNING=3,
  42     /** Trace opens and closes of ICU services  @draft ICU 2.8*/
  43     UTRACE_OPEN_CLOSE=5,
  44     /** Trace an intermediate number of ICU operations  @draft ICU 2.8*/
  45     UTRACE_INFO=7,
  46     /** Trace the maximum number of ICU operations  @draft ICU 2.8*/
  47     UTRACE_VERBOSE=9
  48 } UTraceLevel;
  49
  50 /**
  51  *  These are the ICU functions that will be traced when tracing is enabled.
  52  *  @draft ICU 2.8
  53  */
  54 typedef enum UTraceFunctionNumber {
  55     UTRACE_FUNCTION_START=0,
  56     UTRACE_U_INIT=UTRACE_FUNCTION_START,
  57     UTRACE_U_CLEANUP,
  58     UTRACE_FUNCTION_LIMIT,
  59
  60     UTRACE_CONVERSION_START=0x1000,
  61     UTRACE_UCNV_OPEN=UTRACE_CONVERSION_START,
  62     UTRACE_UCNV_OPEN_PACKAGE,
  63     UTRACE_UCNV_OPEN_ALGORITHMIC,
  64     UTRACE_UCNV_CLONE,
  65     UTRACE_UCNV_CLOSE,
  66     UTRACE_UCNV_FLUSH_CACHE,
  67     UTRACE_UCNV_LOAD,
  68     UTRACE_UCNV_UNLOAD,
  69     UTRACE_CONVERSION_LIMIT,
  70
  71     UTRACE_COLLATION_START=0x2000,
  72     UTRACE_UCOL_OPEN=UTRACE_COLLATION_START,
  73     UTRACE_UCOL_CLOSE,
  74     UTRACE_UCOL_STRCOLL,
  75     UTRACE_UCOL_GET_SORTKEY,
  76     UTRACE_UCOL_GETLOCALE,
  77     UTRACE_UCOL_NEXTSORTKEYPART,
  78     UTRACE_UCOL_STRCOLLITER,
  79     UTRACE_UCOL_OPEN_FROM_SHORT_STRING,
  80     UTRACE_COLLATION_LIMIT
  81 } UTraceFunctionNumber;
  82
  83 #endif /*U_HIDE_DRAFT_API*/
  84
  85 /**
  86  * Setter for the trace level.
  87  * @param traceLevel A UTraceLevel value.
  88  * @draft ICU 2.8
  89  */
  90 U_DRAFT void U_EXPORT2
  91 utrace_setLevel(int32_t traceLevel);
  92
  93 /**
  94  * Getter for the trace level.
  95  * @return The UTraceLevel value being used by ICU.
  96  * @draft ICU 2.8
  97  */
  98 U_DRAFT int32_t U_EXPORT2
  99 utrace_getLevel(void);
 100
 101 /* Trace function pointers types  ----------------------------- */
 102
 103 /**
 104   *  Type signature for the trace function to be called when entering a function.
 105   *  @param context value supplied at the time the trace functions are set.
 106   *  @param fnNumber Enum value indicating the ICU function being entered.
 107   *  @draft ICU 2.8
 108   */
 109 typedef void U_CALLCONV
 110 UTraceEntry(const void *context, int32_t fnNumber);
 111
 112 /**
 113   *  Type signature for the trace function to be called when exiting from a function.
 114   *  @param context value supplied at the time the trace functions are set.
 115   *  @param fnNumber Enum value indicating the ICU function being exited.
 116   *  @param fmt     A formatting string that describes the number and types
 117   *                 of arguments included with the variable args.  The fmt
 118   *                 string has the same form as the utrace_vformat format
 119   *                 string.
 120   *  @param args    A variable arguments list.  Contents are described by
 121   *                 the fmt parameter.
 122   *  @see   utrace_vformat
 123   *  @draft ICU 2.8
 124   */
 125 typedef void U_CALLCONV
 126 UTraceExit(const void *context, int32_t fnNumber,
 127            const char *fmt, va_list args);
 128
 129 /**
 130   *  Type signature for the trace function to be called from within an ICU function
 131   *  to display data or messages.
 132   *  @param context  value supplied at the time the trace functions are set.
 133   *  @param fnNumber Enum value indicating the ICU function being exited.
 134   *  @param level    The current tracing level
 135   *  @param fmt      A format string describing the tracing data that is supplied
 136   *                  as variable args
 137   *  @param args     The data being traced, passed as variable args.
 138   *  @draft ICU 2.8
 139   */
 140 typedef void U_CALLCONV
 141 UTraceData(const void *context, int32_t fnNumber, int32_t level,
 142            const char *fmt, va_list args);
 143
 144 /**
 145   *  Set ICU Tracing functions.  Installs application-provided tracing
 146   *  functions into ICU.  After doing this, subsequent ICU operations
 147   *  will call back to the installed functions, providing a trace
 148   *  of the use of ICU.  Passing a NULL pointer for a tracing function
 149   *  is allowed, and inhibits tracing action at points where that function
 150   *  would be called.
 151   *  <p>
 152   *  Tracing and Threads:  Tracing functions are global to a process, and
 153   *  will be called in response to ICU operations performed by any
 154   *  thread.  If tracing of an individual thread is desired, the
 155   *  tracing functions must themselves filter by checking that the
 156   *  current thread is the desired thread.
 157   *
 158   *  @param context an uninterpretted pointer.  Whatever is passed in
 159   *                 here will in turn be passed to each of the tracing
 160   *                 functions UTraceEntry, UTraceExit and UTraceData.
 161   *                 ICU does not use or alter this pointer.
 162   *  @param e       Callback function to be called on entry to a
 163   *                 a traced ICU function.
 164   *  @param x       Callback function to be called on exit from a
 165   *                 traced ICU function.
 166   *  @param d       Callback function to be called from within a
 167   *                 traced ICU function, for the purpose of providing
 168   *                 data to the trace.
 169   *
 170   *  @draft ICU 2.8
 171   */
 172 U_DRAFT void U_EXPORT2
 173 utrace_setFunctions(const void *context,
 174                     UTraceEntry *e, UTraceExit *x, UTraceData *d);
 175
 176 /**
 177   * Get the currently installed ICU tracing functions.   Note that a null function
 178   *   pointer will be returned if no trace function has been set.
 179   *
 180   * @param context  The currently installed tracing context.
 181   * @param e        The currently installed UTraceEntry function.
 182   * @param x        The currently installed UTraceExit function.
 183   * @param d        The currently installed UTraceData function.
 184   * @draft ICU 2.8
 185   */
 186 U_DRAFT void U_EXPORT2
 187 utrace_getFunctions(const void **context,
 188                     UTraceEntry **e, UTraceExit **x, UTraceData **d);
 189
 190
 191
 192 /*
 193  *
 194  * ICU trace format string syntax
 195  *
 196  * Format Strings are passed to UTraceData functions, and define the
 197  * number and types of the trace data being passed on each call.
 198  *
 199  * The UTraceData function, which is supplied by the application,
 200  * not by ICU, can either forward the trace data (passed via
 201  * varargs) and the format string back to ICU for formatting into
 202  * a displayable string, or it can interpret the format itself,
 203  * and do as it wishes with the trace data.
 204  *
 205  *
 206  * Goals for the format string
 207  * - basic data output
 208  * - easy to use for trace programmer
 209  * - sufficient provision for data types for trace output readability
 210  * - well-defined types and binary portable APIs
 211  *
 212  * Non-goals
 213  * - printf compatibility
 214  * - fancy formatting
 215  * - argument reordering and other internationalization features
 216  *
 217  * ICU trace format strings contain plain text with argument inserts,
 218  * much like standard printf format strings.
 219  * Each insert begins with a '%', then optionally contains a 'v',
 220  * then exactly one type character.
 221  * Two '%' in a row represent a '%' instead of an insert.
 222  * The trace format strings need not have \n at the end.
 223  *
 224  *
 225  * Types
 226  * -----
 227  *
 228  * Type characters:
 229  * - c A char character in the default codepage.
 230  * - s A NUL-terminated char * string in the default codepage.
 231  * - S A UChar * string.  Requires two params, (ptr, length).  Length=-1 for nul term.
 232  * - b A byte (8-bit integer).
 233  * - h A 16-bit integer.  Also a 16 bit Unicode code unit.
 234  * - d A 32-bit integer.  Also a 20 bit Unicode code point value.
 235  * - l A 64-bit integer.
 236  * - p A data pointer.
 237  *
 238  * Vectors
 239  * -------
 240  *
 241  * If the 'v' is not specified, then one item of the specified type
 242  * is passed in.
 243  * If the 'v' (for "vector") is specified, then a vector of items of the
 244  * specified type is passed in, via a pointer to the first item
 245  * and an int32_t value for the length of the vector.
 246  * Length==-1 means zero or NUL termination.  Works for vectors of all types.
 247  *
 248  * Note:  %vS is a vector of (UChar *) strings.  The strings must
 249  *        be nul terminated as there is no way to provide a
 250  *        separate length parameter for each string.  The length
 251  *        parameter (required for all vectors) is the number of
 252  *        strings, not the length of the strings.
 253  *
 254  * Examples
 255  * --------
 256  *
 257  * These examples show the parameters that will be passed to an application's
 258  *   UTraceData() function for various formats.
 259  *
 260  * - the precise formatting is up to the application!
 261  * - the examples use type casts for arguments only to _show_ the types of
 262  *   arguments without needing variable declarations in the examples;
 263  *   the type casts will not be necessary in actual code
 264  *
 265  * UTraceDataFunc(context, fnNumber, level,
 266  *              "There is a character %c in the string %s.",   // Format String
 267  *              (char)c, (const char *)s);                     // varargs parameters
 268  * ->   There is a character 0x42 'B' in the string "Bravo".
 269  *
 270  * UTraceDataFunc(context, fnNumber, level,
 271  *              "Vector of bytes %vb vector of chars %vc",
 272  *              (const uint8_t *)bytes, (int32_t)bytesLength,
 273  *              (const char *)chars, (int32_t)charsLength);
 274  * ->  Vector of bytes
 275  *      42 63 64 3f [4]
 276  *     vector of chars
 277  *      "Bcd?"[4]
 278  *
 279  * UTraceDataFunc(context, fnNumber, level,
 280  *              "An int32_t %d and a whole bunch of them %vd",
 281  *              (int32_t)-5, (const int32_t *)ints, (int32_t)intsLength);
 282  * ->   An int32_t 0xfffffffb and a whole bunch of them
 283  *      fffffffb 00000005 0000010a [3]
 284  *
 285  */
 286
 287
 288
 289 /**
 290   *  Trace output Formatter.  An application's UTraceData tracing functions may call
 291   *                 back to this function to format the trace output in a
 292   *                 human readable form.  Note that a UTraceData function may choose
 293   *                 to not format the data;  it could, for example, save it in
 294   *                 in the raw form it was received (more compact), leaving
 295   *                 formatting for a later trace analyis tool.
 296   *  @param outBuf  pointer to a buffer to receive the formatted output.  Output
 297   *                 will be nul terminated if there is space in the buffer -
 298   *                 if the length of the requested output < the output buffer size.
 299   *  @param capacity  Length of the output buffer.
 300   *  @param indent  Number of spaces to indent the output.  Intended to allow
 301   *                 data displayed from nested functions to be indented for readability.
 302   *  @param fmt     Format specification for the data to output
 303   *  @param args    Data to be formatted.
 304   *  @return        Length of formatted output, including the terminating NUL.
 305   *                 If buffer capacity is insufficient, the required capacity is returned.
 306   *  @draft ICU 2.8
 307   */
 308 U_DRAFT int32_t U_EXPORT2
 309 utrace_vformat(char *outBuf, int32_t capacity,
 310               int32_t indent, const char *fmt,  va_list args);
 311
 312 /**
 313   *  Trace output Formatter.  An application's UTraceData tracing functions may call
 314   *                 this function to format any additional trace data, beyond that
 315   *                 provided by default, in human readable form with the same
 316   *                 formatting conventions used by utrace_vformat().
 317   *  @param outBuf  pointer to a buffer to receive the formatted output.  Output
 318   *                 will be nul terminated if there is space in the buffer -
 319   *                 if the length of the requested output < the output buffer size.
 320   *  @param capacity  Length of the output buffer.
 321   *  @param indent  Number of spaces to indent the output.  Intended to allow
 322   *                 data displayed from nested functions to be indented for readability.
 323   *  @param fmt     Format specification for the data to output
 324   *  @param ...     Data to be formatted.
 325   *  @return        Length of formatted output, including the terminating NUL.
 326   *                 If buffer capacity is insufficient, the required capacity is returned.
 327   *  @draft ICU 2.8
 328   */
 329 U_DRAFT int32_t U_EXPORT2
 330 utrace_format(char *outBuf, int32_t capacity,
 331               int32_t indent, const char *fmt,  ...);
 332
 333
 334
 335 /* Trace function numbers --------------------------------------------------- */
 336
 337 /**
 338  * Get the name of a function from its trace function number.
 339  *
 340  * @param fnNumber The trace number for an ICU function.
 341  * @return The name string for the function.
 342  *
 343  * @see UTraceFunctionNumber
 344  * @draft ICU 2.8
 345  */
 346 U_DRAFT const char * U_EXPORT2
 347 utrace_functionName(int32_t fnNumber);
 348
 349 U_CDECL_END
 350
 351 #endif