gdb/utils.h

   1 /* I/O, string, cleanup, and other random utilities for GDB.
   2    Copyright (C) 1986-2024 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef UTILS_H
  20 #define UTILS_H
  21
  22 #include <chrono>
  23
  24 struct completion_match_for_lcd;
  25 class compiled_regex;
  26
  27 /* String utilities.  */
  28
  29 extern bool sevenbit_strings;
  30
  31 /* Modes of operation for strncmp_iw_with_mode.  */
  32
  33 enum class strncmp_iw_mode
  34 {
  35 /* Do a strcmp() type operation on STRING1 and STRING2, ignoring any
  36    differences in whitespace.  Returns 0 if they match, non-zero if
  37    they don't (slightly different than strcmp()'s range of return
  38    values).  */
  39   NORMAL,
  40
  41   /* Like NORMAL, but also apply the strcmp_iw hack.  I.e.,
  42      string1=="FOO(PARAMS)" matches string2=="FOO".  */
  43   MATCH_PARAMS,
  44 };
  45
  46 /* Helper for strcmp_iw and strncmp_iw.  Exported so that languages
  47    can implement both NORMAL and MATCH_PARAMS variants in a single
  48    function and defer part of the work to strncmp_iw_with_mode.
  49
  50    LANGUAGE is used to implement some context-sensitive
  51    language-specific comparisons.  For example, for C++,
  52    "string1=operator()" should not match "string2=operator" even in
  53    MATCH_PARAMS mode.
  54
  55    MATCH_FOR_LCD is passed down so that the function can mark parts of
  56    the symbol name as ignored for completion matching purposes (e.g.,
  57    to handle abi tags).  If IGNORE_TEMPLATE_PARAMS is true, all template
  58    parameter lists will be ignored when language is C++.  */
  59
  60 extern int strncmp_iw_with_mode
  61   (const char *string1, const char *string2, size_t string2_len,
  62    strncmp_iw_mode mode, enum language language,
  63    completion_match_for_lcd *match_for_lcd = NULL,
  64    bool ignore_template_params = false);
  65
  66 /* Do a strncmp() type operation on STRING1 and STRING2, ignoring any
  67    differences in whitespace.  STRING2_LEN is STRING2's length.
  68    Returns 0 if STRING1 matches STRING2_LEN characters of STRING2,
  69    non-zero otherwise (slightly different than strncmp()'s range of
  70    return values).  Note: passes language_minimal to
  71    strncmp_iw_with_mode, and should therefore be avoided if a more
  72    suitable language is available.  */
  73 extern int strncmp_iw (const char *string1, const char *string2,
  74                        size_t string2_len);
  75
  76 /* Do a strcmp() type operation on STRING1 and STRING2, ignoring any
  77    differences in whitespace.  Returns 0 if they match, non-zero if
  78    they don't (slightly different than strcmp()'s range of return
  79    values).
  80
  81    As an extra hack, string1=="FOO(ARGS)" matches string2=="FOO".
  82    This "feature" is useful when searching for matching C++ function
  83    names (such as if the user types 'break FOO', where FOO is a
  84    mangled C++ function).
  85
  86    Note: passes language_minimal to strncmp_iw_with_mode, and should
  87    therefore be avoided if a more suitable language is available.  */
  88 extern int strcmp_iw (const char *string1, const char *string2);
  89
  90 extern int strcmp_iw_ordered (const char *, const char *);
  91
  92 /* Reset the prompt_for_continue clock.  */
  93 void reset_prompt_for_continue_wait_time (void);
  94 /* Return the time spent in prompt_for_continue.  */
  95 std::chrono::steady_clock::duration get_prompt_for_continue_wait_time ();
  96 \f
  97 /* Parsing utilities.  */
  98
  99 extern int parse_pid_to_attach (const char *args);
 100
 101 extern int parse_escape (struct gdbarch *, const char **);
 102
 103 \f
 104 /* Cleanup utilities.  */
 105
 106 extern void init_page_info (void);
 107
 108 /* Temporarily set BATCH_FLAG and the associated unlimited terminal size.
 109    Restore when destroyed.  */
 110
 111 struct set_batch_flag_and_restore_page_info
 112 {
 113 public:
 114
 115   set_batch_flag_and_restore_page_info ();
 116   ~set_batch_flag_and_restore_page_info ();
 117
 118   DISABLE_COPY_AND_ASSIGN (set_batch_flag_and_restore_page_info);
 119
 120 private:
 121
 122   /* Note that this doesn't use scoped_restore, because it's important
 123      to control the ordering of operations in the destruction, and it
 124      was simpler to avoid introducing a new ad hoc class.  */
 125   unsigned m_save_lines_per_page;
 126   unsigned m_save_chars_per_line;
 127   int m_save_batch_flag;
 128 };
 129
 130 \f
 131 /* Path utilities.  */
 132
 133 extern int gdb_filename_fnmatch (const char *pattern, const char *string,
 134                                  int flags);
 135
 136 extern void substitute_path_component (char **stringp, const char *from,
 137                                        const char *to);
 138
 139 std::string ldirname (const char *filename);
 140
 141 extern int count_path_elements (const char *path);
 142
 143 extern const char *strip_leading_path_elements (const char *path, int n);
 144 \f
 145 /* GDB output, ui_file utilities.  */
 146
 147 struct ui_file;
 148
 149 extern int query (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 150 extern int nquery (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 151 extern int yquery (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 152
 153 extern void begin_line (void);
 154
 155 extern void wrap_here (int);
 156
 157 extern void reinitialize_more_filter (void);
 158
 159 /* Return the number of characters in a line.  */
 160
 161 extern int get_chars_per_line ();
 162
 163 extern bool pagination_enabled;
 164
 165 /* A flag indicating whether to timestamp debugging messages.  */
 166 extern bool debug_timestamp;
 167
 168 extern struct ui_file **current_ui_gdb_stdout_ptr (void);
 169 extern struct ui_file **current_ui_gdb_stdin_ptr (void);
 170 extern struct ui_file **current_ui_gdb_stderr_ptr (void);
 171 extern struct ui_file **current_ui_gdb_stdlog_ptr (void);
 172
 173 /* Flush STREAM.  */
 174 extern void gdb_flush (struct ui_file *stream);
 175
 176 /* The current top level's ui_file streams.  */
 177
 178 /* Normal results */
 179 #define gdb_stdout (*current_ui_gdb_stdout_ptr ())
 180 /* Input stream */
 181 #define gdb_stdin (*current_ui_gdb_stdin_ptr ())
 182 /* Serious error notifications.  This bypasses the pager, if one is in
 183    use.  */
 184 #define gdb_stderr (*current_ui_gdb_stderr_ptr ())
 185 /* Log/debug/trace messages that bypasses the pager, if one is in
 186    use.  */
 187 #define gdb_stdlog (*current_ui_gdb_stdlog_ptr ())
 188
 189 /* Truly global ui_file streams.  These are all defined in main.c.  */
 190
 191 /* Target output that should bypass the pager, if one is in use.  */
 192 extern struct ui_file *gdb_stdtarg;
 193 extern struct ui_file *gdb_stdtargin;
 194
 195 /* Set the screen dimensions to WIDTH and HEIGHT.  */
 196
 197 extern void set_screen_width_and_height (int width, int height);
 198
 199 /* Generic stdio-like operations.  */
 200
 201 extern void gdb_puts (const char *, struct ui_file *);
 202
 203 extern void gdb_puts (const std::string &s, ui_file *stream);
 204
 205 extern void gdb_putc (int c, struct ui_file *);
 206
 207 extern void gdb_putc (int c);
 208
 209 extern void gdb_puts (const char *);
 210
 211 extern void puts_tabular (char *string, int width, int right);
 212
 213 /* Generic printf-like operations.  As an extension over plain
 214    printf, these support some GDB-specific format specifiers.
 215    Particularly useful here are the styling formatters: '%p[', '%p]'
 216    and '%ps'.  See ui_out::message for details.  */
 217
 218 extern void gdb_vprintf (const char *, va_list) ATTRIBUTE_PRINTF (1, 0);
 219
 220 extern void gdb_vprintf (struct ui_file *, const char *, va_list)
 221   ATTRIBUTE_PRINTF (2, 0);
 222
 223 extern void gdb_printf (struct ui_file *, const char *, ...)
 224   ATTRIBUTE_PRINTF (2, 3);
 225
 226 extern void gdb_printf (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 227
 228 extern void printf_unfiltered (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 229
 230 extern void print_spaces (int, struct ui_file *);
 231
 232 extern const char *n_spaces (int);
 233
 234 /* Return nonzero if filtered printing is initialized.  */
 235 extern int filtered_printing_initialized (void);
 236
 237 /* Like gdb_printf, but styles the output according to STYLE,
 238    when appropriate.  */
 239
 240 extern void fprintf_styled (struct ui_file *stream,
 241                             const ui_file_style &style,
 242                             const char *fmt,
 243                             ...)
 244   ATTRIBUTE_PRINTF (3, 4);
 245
 246 /* Like gdb_puts, but styles the output according to STYLE, when
 247    appropriate.  */
 248
 249 extern void fputs_styled (const char *linebuffer,
 250                           const ui_file_style &style,
 251                           struct ui_file *stream);
 252
 253 /* Like fputs_styled, but uses highlight_style to highlight the
 254    parts of STR that match HIGHLIGHT.  */
 255
 256 extern void fputs_highlighted (const char *str, const compiled_regex &highlight,
 257                                struct ui_file *stream);
 258
 259 /* Convert CORE_ADDR to string in platform-specific manner.
 260    This is usually formatted similar to 0x%lx.  */
 261 extern const char *paddress (struct gdbarch *gdbarch, CORE_ADDR addr);
 262
 263 /* Return a string representation in hexadecimal notation of ADDRESS,
 264    which is suitable for printing.  */
 265
 266 extern const char *print_core_address (struct gdbarch *gdbarch,
 267                                        CORE_ADDR address);
 268
 269 extern CORE_ADDR string_to_core_addr (const char *my_string);
 270
 271 extern void fprintf_symbol (struct ui_file *, const char *,
 272                             enum language, int);
 273
 274 extern void perror_warning_with_name (const char *string);
 275
 276 /* Issue a warning formatted as '<filename>: <explanation>', where
 277    <filename> is FILENAME with filename styling applied.  As such, don't
 278    pass anything more than a filename in this string.  The <explanation>
 279    is a string returned from calling safe_strerror(SAVED_ERRNO).  */
 280
 281 extern void warning_filename_and_errno (const char *filename,
 282                                         int saved_errno);
 283 \f
 284 /* Warnings and error messages.  */
 285
 286 extern void (*deprecated_error_begin_hook) (void);
 287
 288 /* Message to be printed before the warning message, when a warning occurs.  */
 289
 290 extern const char *warning_pre_print;
 291
 292 extern void demangler_vwarning (const char *file, int line,
 293                                const char *, va_list ap)
 294      ATTRIBUTE_PRINTF (3, 0);
 295
 296 extern void demangler_warning (const char *file, int line,
 297                               const char *, ...) ATTRIBUTE_PRINTF (3, 4);
 298
 299 \f
 300 /* Misc. utilities.  */
 301
 302 #ifdef HAVE_WAITPID
 303 extern pid_t wait_to_die_with_timeout (pid_t pid, int *status, int timeout);
 304 #endif
 305
 306 extern int myread (int, char *, int);
 307
 308 /* Resource limits used by getrlimit and setrlimit.  */
 309
 310 enum resource_limit_kind
 311   {
 312     LIMIT_CUR,
 313     LIMIT_MAX
 314   };
 315
 316 /* Check whether GDB will be able to dump core using the dump_core
 317    function.  Returns zero if GDB cannot or should not dump core.
 318    If LIMIT_KIND is LIMIT_CUR the user's soft limit will be respected.
 319    If LIMIT_KIND is LIMIT_MAX only the hard limit will be respected.  */
 320
 321 extern int can_dump_core (enum resource_limit_kind limit_kind);
 322
 323 /* Print a warning that we cannot dump core.  */
 324
 325 extern void warn_cant_dump_core (const char *reason);
 326
 327 /* Dump core trying to increase the core soft limit to hard limit
 328    first.  */
 329
 330 extern void dump_core (void);
 331
 332 /* Copy NBITS bits from SOURCE to DEST starting at the given bit
 333    offsets.  Use the bit order as specified by BITS_BIG_ENDIAN.
 334    Source and destination buffers must not overlap.  */
 335
 336 extern void copy_bitwise (gdb_byte *dest, ULONGEST dest_offset,
 337                           const gdb_byte *source, ULONGEST source_offset,
 338                           ULONGEST nbits, int bits_big_endian);
 339
 340 /* When readline decides that the terminal cannot auto-wrap lines, it reduces
 341    the width of the reported screen width by 1.  This variable indicates
 342    whether that's the case or not, allowing us to add it back where
 343    necessary.  See _rl_term_autowrap in readline/terminal.c.  */
 344
 345 extern int readline_hidden_cols;
 346
 347 /* Assign VAL to LVAL, and set CHANGED to true if the assignment changed
 348    LVAL.  */
 349
 350 template<typename T>
 351 void
 352 assign_set_if_changed (T &lval, const T &val, bool &changed)
 353 {
 354   if (lval == val)
 355     return;
 356
 357   lval = val;
 358   changed = true;
 359 }
 360
 361 /* Assign VAL to LVAL, and return true if the assignment changed LVAL.  */
 362
 363 template<typename T>
 364 bool
 365 assign_return_if_changed (T &lval, const T &val)
 366 {
 367   if (lval == val)
 368     return false;
 369
 370   lval = val;
 371   return true;
 372 }
 373
 374 /* A class that can be used to intercept warnings.  A class is used
 375    here, rather than a gdb::function_view because it proved difficult
 376    to use a function view in conjunction with ATTRIBUTE_PRINTF in a
 377    way that would satisfy all compilers on all systems.  And, even
 378    though gdb only ever uses deferred_warnings here, a virtual
 379    function is used to help Insight.  */
 380 struct warning_hook_handler_type
 381 {
 382   virtual void warn (const char *format, va_list args) ATTRIBUTE_PRINTF (2, 0)
 383     = 0;
 384 };
 385
 386 typedef warning_hook_handler_type *warning_hook_handler;
 387
 388 /* Set the thread-local warning hook, and restore the old value when
 389    finished.  */
 390 class scoped_restore_warning_hook
 391 {
 392 public:
 393   explicit scoped_restore_warning_hook (warning_hook_handler new_handler);
 394
 395   ~scoped_restore_warning_hook ();
 396
 397 private:
 398   scoped_restore_warning_hook (const scoped_restore_warning_hook &other)
 399     = delete;
 400   scoped_restore_warning_hook &operator= (const scoped_restore_warning_hook &)
 401     = delete;
 402
 403   warning_hook_handler m_save;
 404 };
 405
 406 /* Return the current warning handler.  */
 407 extern warning_hook_handler get_warning_hook_handler ();
 408
 409 /* In some cases GDB needs to try several different solutions to a problem,
 410    if any of the solutions work then as far as the user is concerned the
 411    problem is solved, and GDB should continue without warnings.  However,
 412    if none of the solutions work then GDB should emit any warnings that
 413    occurred while trying each possible solution.
 414
 415    One example of this is locating separate debug info.  There are several
 416    different approaches for this; following the .gnu_debuglink, a build-id
 417    based lookup, or using debuginfod.  If any works, and debug info is
 418    located, then the user doesn't want to see warnings from the earlier
 419    approaches that were tried and failed.
 420
 421    However, GDB should emit all the warnings using separate calls to
 422    warning -- this ensures that each warning is formatted on its own line,
 423    and that any styling is emitted correctly.
 424
 425    This class helps with deferring warnings.  Warnings can be added to an
 426    instance of this class with the 'warn' function, and all warnings can be
 427    emitted with a single call to 'emit'.  */
 428
 429 struct deferred_warnings final : public warning_hook_handler_type
 430 {
 431   deferred_warnings ()
 432     : m_can_style (gdb_stderr->can_emit_style_escape ())
 433   {
 434   }
 435
 436   /* Add a warning to the list of deferred warnings.  */
 437   void warn (const char *format, ...) ATTRIBUTE_PRINTF (2, 3)
 438   {
 439     va_list args;
 440     va_start (args, format);
 441     this->warn (format, args);
 442     va_end (args);
 443   }
 444
 445   /* A variant of 'warn' so that this object can be used as a warning
 446      hook; see scoped_restore_warning_hook.  Note that no locking is
 447      done, so users have to be careful to only install this into a
 448      single thread at a time.  */
 449   void warn (const char *format, va_list args) override
 450     ATTRIBUTE_PRINTF (2, 0)
 451   {
 452     string_file msg (m_can_style);
 453     msg.vprintf (format, args);
 454     m_warnings.emplace_back (std::move (msg));
 455   }
 456
 457   /* Emit all warnings.  */
 458   void emit () const
 459   {
 460     for (const auto &w : m_warnings)
 461       warning ("%s", w.c_str ());
 462   }
 463
 464 private:
 465
 466   /* True if gdb_stderr supports styling at the moment this object is
 467      constructed.  This is done just once so that objects of this type
 468      can be used off the main thread.  */
 469   bool m_can_style;
 470
 471   /* The list of all deferred warnings.  */
 472   std::vector<string_file> m_warnings;
 473 };
 474
 475 #endif /* UTILS_H */