| 1 | /* The find command. |
| 2 | |
| 3 | Copyright (C) 2008 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 | #include "defs.h" |
| 21 | #include <ctype.h> |
| 22 | #include "gdb_string.h" |
| 23 | #include "gdbcmd.h" |
| 24 | #include "value.h" |
| 25 | #include "target.h" |
| 26 | |
| 27 | /* Copied from bfd_put_bits. */ |
| 28 | |
| 29 | static void |
| 30 | put_bits (bfd_uint64_t data, char *buf, int bits, bfd_boolean big_p) |
| 31 | { |
| 32 | int i; |
| 33 | int bytes; |
| 34 | |
| 35 | gdb_assert (bits % 8 == 0); |
| 36 | |
| 37 | bytes = bits / 8; |
| 38 | for (i = 0; i < bytes; i++) |
| 39 | { |
| 40 | int index = big_p ? bytes - i - 1 : i; |
| 41 | |
| 42 | buf[index] = data & 0xff; |
| 43 | data >>= 8; |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | /* Subroutine of find_command to simplify it. |
| 48 | Parse the arguments of the "find" command. */ |
| 49 | |
| 50 | static void |
| 51 | parse_find_args (char *args, ULONGEST *max_countp, |
| 52 | char **pattern_bufp, ULONGEST *pattern_lenp, |
| 53 | CORE_ADDR *start_addrp, ULONGEST *search_space_lenp) |
| 54 | { |
| 55 | /* Default to using the specified type. */ |
| 56 | char size = '\0'; |
| 57 | ULONGEST max_count = ~(ULONGEST) 0; |
| 58 | /* Buffer to hold the search pattern. */ |
| 59 | char *pattern_buf; |
| 60 | /* Current size of search pattern buffer. |
| 61 | We realloc space as needed. */ |
| 62 | #define INITIAL_PATTERN_BUF_SIZE 100 |
| 63 | ULONGEST pattern_buf_size = INITIAL_PATTERN_BUF_SIZE; |
| 64 | /* Pointer to one past the last in-use part of pattern_buf. */ |
| 65 | char *pattern_buf_end; |
| 66 | ULONGEST pattern_len; |
| 67 | CORE_ADDR start_addr; |
| 68 | ULONGEST search_space_len; |
| 69 | char *s = args; |
| 70 | bfd_boolean big_p = gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG; |
| 71 | struct cleanup *old_cleanups; |
| 72 | struct value *v; |
| 73 | |
| 74 | if (args == NULL) |
| 75 | error (_("Missing search parameters.")); |
| 76 | |
| 77 | pattern_buf = xmalloc (pattern_buf_size); |
| 78 | pattern_buf_end = pattern_buf; |
| 79 | old_cleanups = make_cleanup (free_current_contents, &pattern_buf); |
| 80 | |
| 81 | /* Get search granularity and/or max count if specified. |
| 82 | They may be specified in either order, together or separately. */ |
| 83 | |
| 84 | while (*s == '/') |
| 85 | { |
| 86 | ++s; |
| 87 | |
| 88 | while (*s != '\0' && *s != '/' && !isspace (*s)) |
| 89 | { |
| 90 | if (isdigit (*s)) |
| 91 | { |
| 92 | max_count = atoi (s); |
| 93 | while (isdigit (*s)) |
| 94 | ++s; |
| 95 | continue; |
| 96 | } |
| 97 | |
| 98 | switch (*s) |
| 99 | { |
| 100 | case 'b': |
| 101 | case 'h': |
| 102 | case 'w': |
| 103 | case 'g': |
| 104 | size = *s++; |
| 105 | break; |
| 106 | default: |
| 107 | error (_("Invalid size granularity.")); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | while (isspace (*s)) |
| 112 | ++s; |
| 113 | } |
| 114 | |
| 115 | /* Get the search range. */ |
| 116 | |
| 117 | v = parse_to_comma_and_eval (&s); |
| 118 | start_addr = value_as_address (v); |
| 119 | |
| 120 | if (*s == ',') |
| 121 | ++s; |
| 122 | while (isspace (*s)) |
| 123 | ++s; |
| 124 | |
| 125 | if (*s == '+') |
| 126 | { |
| 127 | LONGEST len; |
| 128 | ++s; |
| 129 | v = parse_to_comma_and_eval (&s); |
| 130 | len = value_as_long (v); |
| 131 | if (len == 0) |
| 132 | { |
| 133 | printf_filtered (_("Empty search range.\n")); |
| 134 | return; |
| 135 | } |
| 136 | if (len < 0) |
| 137 | error (_("Invalid length.")); |
| 138 | /* Watch for overflows. */ |
| 139 | if (len > CORE_ADDR_MAX |
| 140 | || (start_addr + len - 1) < start_addr) |
| 141 | error (_("Search space too large.")); |
| 142 | search_space_len = len; |
| 143 | } |
| 144 | else |
| 145 | { |
| 146 | CORE_ADDR end_addr; |
| 147 | v = parse_to_comma_and_eval (&s); |
| 148 | end_addr = value_as_address (v); |
| 149 | if (start_addr > end_addr) |
| 150 | error (_("Invalid search space, end preceeds start.")); |
| 151 | search_space_len = end_addr - start_addr + 1; |
| 152 | /* We don't support searching all of memory |
| 153 | (i.e. start=0, end = 0xff..ff). |
| 154 | Bail to avoid overflows later on. */ |
| 155 | if (search_space_len == 0) |
| 156 | error (_("Overflow in address range computation, choose smaller range.")); |
| 157 | } |
| 158 | |
| 159 | if (*s == ',') |
| 160 | ++s; |
| 161 | |
| 162 | /* Fetch the search string. */ |
| 163 | |
| 164 | while (*s != '\0') |
| 165 | { |
| 166 | LONGEST x; |
| 167 | int val_bytes; |
| 168 | |
| 169 | while (isspace (*s)) |
| 170 | ++s; |
| 171 | |
| 172 | v = parse_to_comma_and_eval (&s); |
| 173 | val_bytes = TYPE_LENGTH (value_type (v)); |
| 174 | |
| 175 | /* Keep it simple and assume size == 'g' when watching for when we |
| 176 | need to grow the pattern buf. */ |
| 177 | if ((pattern_buf_end - pattern_buf + max (val_bytes, sizeof (int64_t))) |
| 178 | > pattern_buf_size) |
| 179 | { |
| 180 | size_t current_offset = pattern_buf_end - pattern_buf; |
| 181 | pattern_buf_size *= 2; |
| 182 | pattern_buf = xrealloc (pattern_buf, pattern_buf_size); |
| 183 | pattern_buf_end = pattern_buf + current_offset; |
| 184 | } |
| 185 | |
| 186 | if (size != '\0') |
| 187 | { |
| 188 | x = value_as_long (v); |
| 189 | switch (size) |
| 190 | { |
| 191 | case 'b': |
| 192 | *pattern_buf_end++ = x; |
| 193 | break; |
| 194 | case 'h': |
| 195 | put_bits (x, pattern_buf_end, 16, big_p); |
| 196 | pattern_buf_end += sizeof (int16_t); |
| 197 | break; |
| 198 | case 'w': |
| 199 | put_bits (x, pattern_buf_end, 32, big_p); |
| 200 | pattern_buf_end += sizeof (int32_t); |
| 201 | break; |
| 202 | case 'g': |
| 203 | put_bits (x, pattern_buf_end, 64, big_p); |
| 204 | pattern_buf_end += sizeof (int64_t); |
| 205 | break; |
| 206 | } |
| 207 | } |
| 208 | else |
| 209 | { |
| 210 | memcpy (pattern_buf_end, value_contents_raw (v), val_bytes); |
| 211 | pattern_buf_end += val_bytes; |
| 212 | } |
| 213 | |
| 214 | if (*s == ',') |
| 215 | ++s; |
| 216 | while (isspace (*s)) |
| 217 | ++s; |
| 218 | } |
| 219 | |
| 220 | if (pattern_buf_end == pattern_buf) |
| 221 | error (_("Missing search pattern.")); |
| 222 | |
| 223 | pattern_len = pattern_buf_end - pattern_buf; |
| 224 | |
| 225 | if (search_space_len < pattern_len) |
| 226 | error (_("Search space too small to contain pattern.")); |
| 227 | |
| 228 | *max_countp = max_count; |
| 229 | *pattern_bufp = pattern_buf; |
| 230 | *pattern_lenp = pattern_len; |
| 231 | *start_addrp = start_addr; |
| 232 | *search_space_lenp = search_space_len; |
| 233 | |
| 234 | /* We successfully parsed the arguments, leave the freeing of PATTERN_BUF |
| 235 | to the caller now. */ |
| 236 | discard_cleanups (old_cleanups); |
| 237 | } |
| 238 | |
| 239 | static void |
| 240 | find_command (char *args, int from_tty) |
| 241 | { |
| 242 | /* Command line parameters. |
| 243 | These are initialized to avoid uninitialized warnings from -Wall. */ |
| 244 | ULONGEST max_count = 0; |
| 245 | char *pattern_buf = 0; |
| 246 | ULONGEST pattern_len = 0; |
| 247 | CORE_ADDR start_addr = 0; |
| 248 | ULONGEST search_space_len = 0; |
| 249 | /* End of command line parameters. */ |
| 250 | unsigned int found_count; |
| 251 | CORE_ADDR last_found_addr; |
| 252 | struct cleanup *old_cleanups; |
| 253 | |
| 254 | parse_find_args (args, &max_count, &pattern_buf, &pattern_len, |
| 255 | &start_addr, &search_space_len); |
| 256 | |
| 257 | old_cleanups = make_cleanup (free_current_contents, &pattern_buf); |
| 258 | |
| 259 | /* Perform the search. */ |
| 260 | |
| 261 | found_count = 0; |
| 262 | last_found_addr = 0; |
| 263 | |
| 264 | while (search_space_len >= pattern_len |
| 265 | && found_count < max_count) |
| 266 | { |
| 267 | /* Offset from start of this iteration to the next iteration. */ |
| 268 | ULONGEST next_iter_incr; |
| 269 | CORE_ADDR found_addr; |
| 270 | int found = target_search_memory (start_addr, search_space_len, |
| 271 | pattern_buf, pattern_len, &found_addr); |
| 272 | |
| 273 | if (found <= 0) |
| 274 | break; |
| 275 | |
| 276 | print_address (found_addr, gdb_stdout); |
| 277 | printf_filtered ("\n"); |
| 278 | ++found_count; |
| 279 | last_found_addr = found_addr; |
| 280 | |
| 281 | /* Begin next iteration at one byte past this match. */ |
| 282 | next_iter_incr = (found_addr - start_addr) + 1; |
| 283 | |
| 284 | /* For robustness, we don't let search_space_len go -ve here. */ |
| 285 | if (search_space_len >= next_iter_incr) |
| 286 | search_space_len -= next_iter_incr; |
| 287 | else |
| 288 | search_space_len = 0; |
| 289 | start_addr += next_iter_incr; |
| 290 | } |
| 291 | |
| 292 | /* Record and print the results. */ |
| 293 | |
| 294 | set_internalvar (lookup_internalvar ("numfound"), |
| 295 | value_from_longest (builtin_type_int, |
| 296 | (LONGEST) found_count)); |
| 297 | if (found_count > 0) |
| 298 | { |
| 299 | set_internalvar (lookup_internalvar ("_"), |
| 300 | value_from_pointer (builtin_type_void_data_ptr, |
| 301 | last_found_addr)); |
| 302 | } |
| 303 | |
| 304 | if (found_count == 0) |
| 305 | printf_filtered ("Pattern not found.\n"); |
| 306 | else |
| 307 | printf_filtered ("%d pattern%s found.\n", found_count, |
| 308 | found_count > 1 ? "s" : ""); |
| 309 | |
| 310 | do_cleanups (old_cleanups); |
| 311 | } |
| 312 | |
| 313 | void |
| 314 | _initialize_mem_search (void) |
| 315 | { |
| 316 | add_cmd ("find", class_vars, find_command, _("\ |
| 317 | Search memory for a sequence of bytes.\n\ |
| 318 | Usage:\n\ |
| 319 | find [/size-char] [/max-count] start-address, end-address, expr1 [, expr2 ...]\n\ |
| 320 | find [/size-char] [/max-count] start-address, +length, expr1 [, expr2 ...]\n\ |
| 321 | size-char is one of b,h,w,g for 8,16,32,64 bit values respectively,\n\ |
| 322 | and if not specified the size is taken from the type of the expression\n\ |
| 323 | in the current language.\n\ |
| 324 | Note that this means for example that in the case of C-like languages\n\ |
| 325 | a search for an untyped 0x42 will search for \"(int) 0x42\"\n\ |
| 326 | which is typically four bytes.\n\ |
| 327 | \n\ |
| 328 | The address of the last match is stored as the value of \"$_\".\n\ |
| 329 | Convenience variable \"$numfound\" is set to the number of matches."), |
| 330 | &cmdlist); |
| 331 | } |