gdbsupport/common-utils.h

   1 /* Shared general utility routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef COMMON_COMMON_UTILS_H
  21 #define COMMON_COMMON_UTILS_H
  22
  23 #include <string>
  24 #include <vector>
  25
  26 #include "poison.h"
  27
  28 /* If possible, define FUNCTION_NAME, a macro containing the name of
  29    the function being defined.  Since this macro may not always be
  30    defined, all uses must be protected by appropriate macro definition
  31    checks (Eg: "#ifdef FUNCTION_NAME").
  32
  33    Version 2.4 and later of GCC define a magical variable `__PRETTY_FUNCTION__'
  34    which contains the name of the function currently being defined.
  35    This is broken in G++ before version 2.6.
  36    C9x has a similar variable called __func__, but prefer the GCC one since
  37    it demangles C++ function names.  */
  38 #if (GCC_VERSION >= 2004)
  39 #define FUNCTION_NAME           __PRETTY_FUNCTION__
  40 #else
  41 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
  42 #define FUNCTION_NAME           __func__  /* ARI: func */
  43 #endif
  44 #endif
  45
  46 #include "gdb_string_view.h"
  47
  48 /* xmalloc(), xrealloc() and xcalloc() have already been declared in
  49    "libiberty.h". */
  50
  51 /* Like xmalloc, but zero the memory.  */
  52 void *xzalloc (size_t);
  53
  54 template <typename T>
  55 static void
  56 xfree (T *ptr)
  57 {
  58   static_assert (IsFreeable<T>::value, "Trying to use xfree with a non-POD \
  59 data type.  Use operator delete instead.");
  60
  61   if (ptr != NULL)
  62     free (ptr);         /* ARI: free */
  63 }
  64
  65
  66 /* Like asprintf and vasprintf, but return the string, throw an error
  67    if no memory.  */
  68 char *xstrprintf (const char *format, ...) ATTRIBUTE_PRINTF (1, 2);
  69 char *xstrvprintf (const char *format, va_list ap)
  70      ATTRIBUTE_PRINTF (1, 0);
  71
  72 /* Like snprintf, but throw an error if the output buffer is too small.  */
  73 int xsnprintf (char *str, size_t size, const char *format, ...)
  74      ATTRIBUTE_PRINTF (3, 4);
  75
  76 /* Returns a std::string built from a printf-style format string.  */
  77 std::string string_printf (const char* fmt, ...)
  78   ATTRIBUTE_PRINTF (1, 2);
  79
  80 /* Like string_printf, but takes a va_list.  */
  81 std::string string_vprintf (const char* fmt, va_list args)
  82   ATTRIBUTE_PRINTF (1, 0);
  83
  84 /* Like string_printf, but appends to DEST instead of returning a new
  85    std::string.  */
  86 void string_appendf (std::string &dest, const char* fmt, ...)
  87   ATTRIBUTE_PRINTF (2, 3);
  88
  89 /* Like string_appendf, but takes a va_list.  */
  90 void string_vappendf (std::string &dest, const char* fmt, va_list args)
  91   ATTRIBUTE_PRINTF (2, 0);
  92
  93 /* Make a copy of the string at PTR with LEN characters
  94    (and add a null character at the end in the copy).
  95    Uses malloc to get the space.  Returns the address of the copy.  */
  96
  97 char *savestring (const char *ptr, size_t len);
  98
  99 /* Extract the next word from ARG.  The next word is defined as either,
 100    everything up to the next space, or, if the next word starts with either
 101    a single or double quote, then everything up to the closing quote.  The
 102    enclosing quotes are not returned in the result string.  The pointer in
 103    ARG is updated to point to the first character after the end of the
 104    word, or, for quoted words, the first character after the closing
 105    quote.  */
 106
 107 std::string extract_string_maybe_quoted (const char **arg);
 108
 109 /* The strerror() function can return NULL for errno values that are
 110    out of range.  Provide a "safe" version that always returns a
 111    printable string.  This version is also thread-safe.  */
 112
 113 extern const char *safe_strerror (int);
 114
 115 /* Return true if the start of STRING matches PATTERN, false otherwise.  */
 116
 117 static inline bool
 118 startswith (const char *string, const char *pattern)
 119 {
 120   return strncmp (string, pattern, strlen (pattern)) == 0;
 121 }
 122
 123 /* Version of startswith that takes string_view arguments.  See comment
 124    above.  */
 125
 126 static inline bool
 127 startswith (gdb::string_view string, gdb::string_view pattern)
 128 {
 129   return (string.length () >= pattern.length ()
 130           && strncmp (string.data (), pattern.data (), pattern.length ()) == 0);
 131 }
 132
 133 ULONGEST strtoulst (const char *num, const char **trailer, int base);
 134
 135 /* Skip leading whitespace characters in INP, returning an updated
 136    pointer.  If INP is NULL, return NULL.  */
 137
 138 extern char *skip_spaces (char *inp);
 139
 140 /* A const-correct version of the above.  */
 141
 142 extern const char *skip_spaces (const char *inp);
 143
 144 /* Skip leading non-whitespace characters in INP, returning an updated
 145    pointer.  If INP is NULL, return NULL.  */
 146
 147 extern char *skip_to_space (char *inp);
 148
 149 /* A const-correct version of the above.  */
 150
 151 extern const char *skip_to_space (const char *inp);
 152
 153 /* Assumes that V is an argv for a program, and iterates through
 154    freeing all the elements.  */
 155 extern void free_vector_argv (std::vector<char *> &v);
 156
 157 /* Return true if VALUE is in [LOW, HIGH].  */
 158
 159 template <typename T>
 160 static bool
 161 in_inclusive_range (T value, T low, T high)
 162 {
 163   return value >= low && value <= high;
 164 }
 165
 166 /* Ensure that V is aligned to an N byte boundary (B's assumed to be a
 167    power of 2).  Round up/down when necessary.  Examples of correct
 168    use include:
 169
 170     addr = align_up (addr, 8); -- VALUE needs 8 byte alignment
 171     write_memory (addr, value, len);
 172     addr += len;
 173
 174    and:
 175
 176     sp = align_down (sp - len, 16); -- Keep SP 16 byte aligned
 177     write_memory (sp, value, len);
 178
 179    Note that uses such as:
 180
 181     write_memory (addr, value, len);
 182     addr += align_up (len, 8);
 183
 184    and:
 185
 186     sp -= align_up (len, 8);
 187     write_memory (sp, value, len);
 188
 189    are typically not correct as they don't ensure that the address (SP
 190    or ADDR) is correctly aligned (relying on previous alignment to
 191    keep things right).  This is also why the methods are called
 192    "align_..." instead of "round_..." as the latter reads better with
 193    this incorrect coding style.  */
 194
 195 extern ULONGEST align_up (ULONGEST v, int n);
 196 extern ULONGEST align_down (ULONGEST v, int n);
 197
 198 #endif /* COMMON_COMMON_UTILS_H */