| 1 | /* |
| 2 | * Copyright (C) 2017 - Philippe Proulx <pproulx@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License, version 2 only, as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 11 | * more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along with |
| 14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 16 | */ |
| 17 | |
| 18 | #define _LGPL_SOURCE |
| 19 | #include <stdlib.h> |
| 20 | #include <string.h> |
| 21 | #include <stdbool.h> |
| 22 | #include <assert.h> |
| 23 | |
| 24 | #include "string-utils.h" |
| 25 | #include "../macros.h" |
| 26 | |
| 27 | enum star_glob_pattern_type_flags { |
| 28 | STAR_GLOB_PATTERN_TYPE_FLAG_NONE = 0, |
| 29 | STAR_GLOB_PATTERN_TYPE_FLAG_PATTERN = 1, |
| 30 | STAR_GLOB_PATTERN_TYPE_FLAG_END_ONLY = 2, |
| 31 | }; |
| 32 | |
| 33 | /* |
| 34 | * Normalizes the star-only globbing pattern `pattern`, that is, crushes |
| 35 | * consecutive `*` characters into a single `*`, avoiding `\*`. |
| 36 | */ |
| 37 | LTTNG_HIDDEN |
| 38 | void strutils_normalize_star_glob_pattern(char *pattern) |
| 39 | { |
| 40 | const char *p; |
| 41 | char *np; |
| 42 | bool got_star = false; |
| 43 | |
| 44 | assert(pattern); |
| 45 | |
| 46 | for (p = pattern, np = pattern; *p != '\0'; p++) { |
| 47 | switch (*p) { |
| 48 | case '*': |
| 49 | if (got_star) { |
| 50 | /* Avoid consecutive stars. */ |
| 51 | continue; |
| 52 | } |
| 53 | |
| 54 | got_star = true; |
| 55 | break; |
| 56 | case '\\': |
| 57 | /* Copy backslash character. */ |
| 58 | *np = *p; |
| 59 | np++; |
| 60 | p++; |
| 61 | |
| 62 | if (*p == '\0') { |
| 63 | goto end; |
| 64 | } |
| 65 | |
| 66 | /* Fall through default case. */ |
| 67 | default: |
| 68 | got_star = false; |
| 69 | break; |
| 70 | } |
| 71 | |
| 72 | /* Copy single character. */ |
| 73 | *np = *p; |
| 74 | np++; |
| 75 | } |
| 76 | |
| 77 | end: |
| 78 | *np = '\0'; |
| 79 | } |
| 80 | |
| 81 | static |
| 82 | enum star_glob_pattern_type_flags strutils_test_glob_pattern(const char *pattern) |
| 83 | { |
| 84 | enum star_glob_pattern_type_flags ret = |
| 85 | STAR_GLOB_PATTERN_TYPE_FLAG_NONE; |
| 86 | const char *p; |
| 87 | |
| 88 | assert(pattern); |
| 89 | |
| 90 | for (p = pattern; *p != '\0'; p++) { |
| 91 | switch (*p) { |
| 92 | case '*': |
| 93 | ret = STAR_GLOB_PATTERN_TYPE_FLAG_PATTERN; |
| 94 | |
| 95 | if (p[1] == '\0') { |
| 96 | ret |= STAR_GLOB_PATTERN_TYPE_FLAG_END_ONLY; |
| 97 | } |
| 98 | |
| 99 | goto end; |
| 100 | case '\\': |
| 101 | p++; |
| 102 | |
| 103 | if (*p == '\0') { |
| 104 | goto end; |
| 105 | } |
| 106 | break; |
| 107 | default: |
| 108 | break; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | end: |
| 113 | return ret; |
| 114 | } |
| 115 | |
| 116 | /* |
| 117 | * Returns true if `pattern` is a star-only globbing pattern, that is, |
| 118 | * it contains at least one non-escaped `*`. |
| 119 | */ |
| 120 | LTTNG_HIDDEN |
| 121 | bool strutils_is_star_glob_pattern(const char *pattern) |
| 122 | { |
| 123 | return strutils_test_glob_pattern(pattern) & |
| 124 | STAR_GLOB_PATTERN_TYPE_FLAG_PATTERN; |
| 125 | } |
| 126 | |
| 127 | /* |
| 128 | * Returns true if `pattern` is a globbing pattern with a globbing, |
| 129 | * non-escaped star only at its very end. |
| 130 | */ |
| 131 | LTTNG_HIDDEN |
| 132 | bool strutils_is_star_at_the_end_only_glob_pattern(const char *pattern) |
| 133 | { |
| 134 | return strutils_test_glob_pattern(pattern) & |
| 135 | STAR_GLOB_PATTERN_TYPE_FLAG_END_ONLY; |
| 136 | } |
| 137 | |
| 138 | /* |
| 139 | * Unescapes the input string `input`, that is, in a `\x` sequence, |
| 140 | * removes `\`. If `only_char` is not 0, only this character is |
| 141 | * escaped. |
| 142 | */ |
| 143 | LTTNG_HIDDEN |
| 144 | char *strutils_unescape_string(const char *input, char only_char) |
| 145 | { |
| 146 | char *output; |
| 147 | char *o; |
| 148 | const char *i; |
| 149 | |
| 150 | assert(input); |
| 151 | output = zmalloc(strlen(input) + 1); |
| 152 | if (!output) { |
| 153 | goto end; |
| 154 | } |
| 155 | |
| 156 | for (i = input, o = output; *i != '\0'; i++) { |
| 157 | switch (*i) { |
| 158 | case '\\': |
| 159 | if (only_char && i[1] != only_char) { |
| 160 | break; |
| 161 | } |
| 162 | |
| 163 | i++; |
| 164 | |
| 165 | if (*i == '\0') { |
| 166 | /* Copy last `\`. */ |
| 167 | *o = '\\'; |
| 168 | o++; |
| 169 | goto end; |
| 170 | } |
| 171 | default: |
| 172 | break; |
| 173 | } |
| 174 | |
| 175 | /* Copy single character. */ |
| 176 | *o = *i; |
| 177 | o++; |
| 178 | } |
| 179 | |
| 180 | end: |
| 181 | return output; |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * Frees a null-terminated array of strings, including each contained |
| 186 | * string. |
| 187 | */ |
| 188 | LTTNG_HIDDEN |
| 189 | void strutils_free_null_terminated_array_of_strings(char **array) |
| 190 | { |
| 191 | char **item; |
| 192 | |
| 193 | if (!array) { |
| 194 | return; |
| 195 | } |
| 196 | |
| 197 | for (item = array; *item; item++) { |
| 198 | free(*item); |
| 199 | } |
| 200 | |
| 201 | free(array); |
| 202 | } |
| 203 | |
| 204 | /* |
| 205 | * Splits the input string `input` using the given delimiter `delim`. |
| 206 | * |
| 207 | * The return value is an allocated null-terminated array of the |
| 208 | * resulting substrings (also allocated). You can free this array and |
| 209 | * its content with strutils_free_null_terminated_array_of_strings(). You |
| 210 | * can get the number of substrings in it with |
| 211 | * strutils_array_of_strings_len(). |
| 212 | * |
| 213 | * Empty substrings are part of the result. For example: |
| 214 | * |
| 215 | * Input: ,hello,,there, |
| 216 | * Result: |
| 217 | * `` |
| 218 | * `hello` |
| 219 | * `` |
| 220 | * `there` |
| 221 | * `` |
| 222 | * |
| 223 | * If `escape_delim` is true, then `\,`, where `,` is the delimiter, |
| 224 | * escapes the delimiter and is copied as `,` only in the resulting |
| 225 | * substring. For example: |
| 226 | * |
| 227 | * Input: hello\,world,zoom,\,hi |
| 228 | * Result: |
| 229 | * `hello,world` |
| 230 | * `zoom` |
| 231 | * `,hi` |
| 232 | * |
| 233 | * Other characters are not escaped (this is the caller's job if |
| 234 | * needed). However they are considering during the parsing, that is, |
| 235 | * `\x`, where `x` is any character, is copied as is to the resulting |
| 236 | * substring, e.g.: |
| 237 | * |
| 238 | * Input: hello\,wo\rld\\,zoom\, |
| 239 | * Result: |
| 240 | * `hello,wo\rld\\` |
| 241 | * `zoom,` |
| 242 | * |
| 243 | * If `escape_delim` is false, nothing at all is escaped, and `delim`, |
| 244 | * when found in `input`, is always a delimiter, e.g.: |
| 245 | * |
| 246 | * Input: hello\,world,zoom,\,hi |
| 247 | * Result: |
| 248 | * `hello\` |
| 249 | * `world` |
| 250 | * `zoom` |
| 251 | * `\` |
| 252 | * `hi` |
| 253 | * |
| 254 | * Returns NULL if there's an error. |
| 255 | */ |
| 256 | LTTNG_HIDDEN |
| 257 | char **strutils_split(const char *input, char delim, bool escape_delim) |
| 258 | { |
| 259 | size_t at; |
| 260 | size_t number_of_substrings = 1; |
| 261 | size_t longest_substring_len = 0; |
| 262 | const char *s; |
| 263 | const char *last; |
| 264 | char **substrings = NULL; |
| 265 | |
| 266 | assert(input); |
| 267 | assert(!(escape_delim && delim == '\\')); |
| 268 | assert(delim != '\0'); |
| 269 | |
| 270 | /* First pass: count the number of substrings. */ |
| 271 | for (s = input, last = input - 1; *s != '\0'; s++) { |
| 272 | if (escape_delim && *s == '\\') { |
| 273 | /* Ignore following (escaped) character. */ |
| 274 | s++; |
| 275 | |
| 276 | if (*s == '\0') { |
| 277 | break; |
| 278 | } |
| 279 | |
| 280 | continue; |
| 281 | } |
| 282 | |
| 283 | if (*s == delim) { |
| 284 | size_t last_len = s - last - 1; |
| 285 | last = s; |
| 286 | number_of_substrings++; |
| 287 | |
| 288 | if (last_len > longest_substring_len) { |
| 289 | longest_substring_len = last_len; |
| 290 | } |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | if ((s - last - 1) > longest_substring_len) { |
| 295 | longest_substring_len = s - last - 1; |
| 296 | } |
| 297 | |
| 298 | substrings = calloc(number_of_substrings + 1, sizeof(*substrings)); |
| 299 | if (!substrings) { |
| 300 | goto error; |
| 301 | } |
| 302 | |
| 303 | /* Second pass: actually split and copy substrings. */ |
| 304 | for (at = 0, s = input; at < number_of_substrings; at++) { |
| 305 | const char *ss; |
| 306 | char *d; |
| 307 | |
| 308 | substrings[at] = zmalloc(longest_substring_len + 1); |
| 309 | if (!substrings[at]) { |
| 310 | goto error; |
| 311 | } |
| 312 | |
| 313 | /* |
| 314 | * Copy characters to substring until we find the next |
| 315 | * delimiter or the end of the input string. |
| 316 | */ |
| 317 | for (ss = s, d = substrings[at]; *ss != '\0'; ss++) { |
| 318 | if (escape_delim && *ss == '\\') { |
| 319 | if (ss[1] == delim) { |
| 320 | /* |
| 321 | * '\' followed by delimiter and |
| 322 | * we need to escape this ('\' |
| 323 | * won't be part of the |
| 324 | * resulting substring). |
| 325 | */ |
| 326 | ss++; |
| 327 | *d = *ss; |
| 328 | d++; |
| 329 | continue; |
| 330 | } else { |
| 331 | /* |
| 332 | * Copy '\' and the following |
| 333 | * character. |
| 334 | */ |
| 335 | *d = *ss; |
| 336 | d++; |
| 337 | ss++; |
| 338 | |
| 339 | if (*ss == '\0') { |
| 340 | break; |
| 341 | } |
| 342 | } |
| 343 | } else if (*ss == delim) { |
| 344 | /* We're done with this substring. */ |
| 345 | break; |
| 346 | } |
| 347 | |
| 348 | *d = *ss; |
| 349 | d++; |
| 350 | } |
| 351 | |
| 352 | /* Next substring starts after the last delimiter. */ |
| 353 | s = ss + 1; |
| 354 | } |
| 355 | |
| 356 | goto end; |
| 357 | |
| 358 | error: |
| 359 | strutils_free_null_terminated_array_of_strings(substrings); |
| 360 | substrings = NULL; |
| 361 | end: |
| 362 | return substrings; |
| 363 | } |
| 364 | |
| 365 | LTTNG_HIDDEN |
| 366 | size_t strutils_array_of_strings_len(char * const *array) |
| 367 | { |
| 368 | char * const *item; |
| 369 | size_t count = 0; |
| 370 | |
| 371 | assert(array); |
| 372 | |
| 373 | for (item = array; *item; item++) { |
| 374 | count++; |
| 375 | } |
| 376 | |
| 377 | return count; |
| 378 | } |