gdbsupport/common-utils.h

   1 /* Shared general utility routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2022 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 #include "gdbsupport/byte-vector.h"
  26 #include "gdbsupport/gdb_unique_ptr.h"
  27 #include "poison.h"
  28 #include "gdb_string_view.h"
  29
  30 /* xmalloc(), xrealloc() and xcalloc() have already been declared in
  31    "libiberty.h". */
  32
  33 /* Like xmalloc, but zero the memory.  */
  34 void *xzalloc (size_t);
  35
  36 /* Like asprintf and vasprintf, but return the string, throw an error
  37    if no memory.  */
  38 gdb::unique_xmalloc_ptr<char> xstrprintf (const char *format, ...)
  39      ATTRIBUTE_PRINTF (1, 2);
  40 gdb::unique_xmalloc_ptr<char> xstrvprintf (const char *format, va_list ap)
  41      ATTRIBUTE_PRINTF (1, 0);
  42
  43 /* Like snprintf, but throw an error if the output buffer is too small.  */
  44 int xsnprintf (char *str, size_t size, const char *format, ...)
  45      ATTRIBUTE_PRINTF (3, 4);
  46
  47 /* Returns a std::string built from a printf-style format string.  */
  48 std::string string_printf (const char* fmt, ...)
  49   ATTRIBUTE_PRINTF (1, 2);
  50
  51 /* Like string_printf, but takes a va_list.  */
  52 std::string string_vprintf (const char* fmt, va_list args)
  53   ATTRIBUTE_PRINTF (1, 0);
  54
  55 /* Like string_printf, but appends to DEST instead of returning a new
  56    std::string.  */
  57 std::string &string_appendf (std::string &dest, const char* fmt, ...)
  58   ATTRIBUTE_PRINTF (2, 3);
  59
  60 /* Like string_appendf, but takes a va_list.  */
  61 std::string &string_vappendf (std::string &dest, const char* fmt, va_list args)
  62   ATTRIBUTE_PRINTF (2, 0);
  63
  64 /* Make a copy of the string at PTR with LEN characters
  65    (and add a null character at the end in the copy).
  66    Uses malloc to get the space.  Returns the address of the copy.  */
  67
  68 char *savestring (const char *ptr, size_t len);
  69
  70 /* Extract the next word from ARG.  The next word is defined as either,
  71    everything up to the next space, or, if the next word starts with either
  72    a single or double quote, then everything up to the closing quote.  The
  73    enclosing quotes are not returned in the result string.  The pointer in
  74    ARG is updated to point to the first character after the end of the
  75    word, or, for quoted words, the first character after the closing
  76    quote.  */
  77
  78 std::string extract_string_maybe_quoted (const char **arg);
  79
  80 /* The strerror() function can return NULL for errno values that are
  81    out of range.  Provide a "safe" version that always returns a
  82    printable string.  This version is also thread-safe.  */
  83
  84 extern const char *safe_strerror (int);
  85
  86 /* Version of startswith that takes string_view arguments.  Return
  87    true if the start of STRING matches PATTERN, false otherwise.  */
  88
  89 static inline bool
  90 startswith (gdb::string_view string, gdb::string_view pattern)
  91 {
  92   return (string.length () >= pattern.length ()
  93           && strncmp (string.data (), pattern.data (), pattern.length ()) == 0);
  94 }
  95
  96 /* Return true if the strings are equal.  */
  97
  98 static inline bool
  99 streq (const char *lhs, const char *rhs)
 100 {
 101   return strcmp (lhs, rhs) == 0;
 102 }
 103
 104 /* Compare C strings for std::sort.  */
 105
 106 static inline bool
 107 compare_cstrings (const char *str1, const char *str2)
 108 {
 109   return strcmp (str1, str2) < 0;
 110 }
 111
 112 ULONGEST strtoulst (const char *num, const char **trailer, int base);
 113
 114 /* Skip leading whitespace characters in INP, returning an updated
 115    pointer.  If INP is NULL, return NULL.  */
 116
 117 extern char *skip_spaces (char *inp);
 118
 119 /* A const-correct version of the above.  */
 120
 121 extern const char *skip_spaces (const char *inp);
 122
 123 /* Skip leading non-whitespace characters in INP, returning an updated
 124    pointer.  If INP is NULL, return NULL.  */
 125
 126 extern char *skip_to_space (char *inp);
 127
 128 /* A const-correct version of the above.  */
 129
 130 extern const char *skip_to_space (const char *inp);
 131
 132 /* Assumes that V is an argv for a program, and iterates through
 133    freeing all the elements.  */
 134 extern void free_vector_argv (std::vector<char *> &v);
 135
 136 /* Return true if VALUE is in [LOW, HIGH].  */
 137
 138 template <typename T>
 139 static bool
 140 in_inclusive_range (T value, T low, T high)
 141 {
 142   return value >= low && value <= high;
 143 }
 144
 145 /* Ensure that V is aligned to an N byte boundary (N's assumed to be a
 146    power of 2).  Round up/down when necessary.  Examples of correct
 147    use include:
 148
 149     addr = align_up (addr, 8); -- VALUE needs 8 byte alignment
 150     write_memory (addr, value, len);
 151     addr += len;
 152
 153    and:
 154
 155     sp = align_down (sp - len, 16); -- Keep SP 16 byte aligned
 156     write_memory (sp, value, len);
 157
 158    Note that uses such as:
 159
 160     write_memory (addr, value, len);
 161     addr += align_up (len, 8);
 162
 163    and:
 164
 165     sp -= align_up (len, 8);
 166     write_memory (sp, value, len);
 167
 168    are typically not correct as they don't ensure that the address (SP
 169    or ADDR) is correctly aligned (relying on previous alignment to
 170    keep things right).  This is also why the methods are called
 171    "align_..." instead of "round_..." as the latter reads better with
 172    this incorrect coding style.  */
 173
 174 extern ULONGEST align_up (ULONGEST v, int n);
 175 extern ULONGEST align_down (ULONGEST v, int n);
 176
 177 /* Convert hex digit A to a number, or throw an exception.  */
 178 extern int fromhex (int a);
 179
 180 /* HEX is a string of characters representing hexadecimal digits.
 181    Convert pairs of hex digits to bytes and store sequentially into
 182    BIN.  COUNT is the maximum number of characters to convert.  This
 183    will convert fewer characters if the number of hex characters
 184    actually seen is odd, or if HEX terminates before COUNT characters.
 185    Returns the number of characters actually converted.  */
 186 extern int hex2bin (const char *hex, gdb_byte *bin, int count);
 187
 188 /* Like the above, but return a gdb::byte_vector.  */
 189 gdb::byte_vector hex2bin (const char *hex);
 190
 191 #endif /* COMMON_COMMON_UTILS_H */