1 /* Dependency generator for Makefile fragments. 2 Copyright (C) 2000-2018 Free Software Foundation, Inc. 3 Contributed by Zack Weinberg, Mar 2000 4 5 This program is free software; you can redistribute it and/or modify it 6 under the terms of the GNU General Public License as published by the 7 Free Software Foundation; either version 3, or (at your option) any 8 later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; see the file COPYING3. If not see 17 <http://www.gnu.org/licenses/>. 18 19 In other words, you are welcome to use, share and improve this program. 20 You are forbidden to forbid anyone else to use, share and improve 21 what you give them. Help stamp out software-hoarding! */ 22 23 #include "config.h" 24 #include "system.h" 25 #include "mkdeps.h" 26 27 /* Keep this structure local to this file, so clients don't find it 28 easy to start making assumptions. */ 29 struct deps 30 { 31 const char **targetv; 32 unsigned int ntargets; /* number of slots actually occupied */ 33 unsigned int targets_size; /* amt of allocated space - in words */ 34 35 const char **depv; 36 unsigned int ndeps; 37 unsigned int deps_size; 38 39 const char **vpathv; 40 size_t *vpathlv; 41 unsigned int nvpaths; 42 unsigned int vpaths_size; 43 }; 44 45 static const char *munge (const char *); 46 47 /* Given a filename, quote characters in that filename which are 48 significant to Make. Note that it's not possible to quote all such 49 characters - e.g. \n, %, *, ?, [, \ (in some contexts), and ~ are 50 not properly handled. It isn't possible to get this right in any 51 current version of Make. (??? Still true? Old comment referred to 52 3.76.1.) */ 53 54 static const char * 55 munge (const char *filename) 56 { 57 int len; 58 const char *p, *q; 59 char *dst, *buffer; 60 61 for (p = filename, len = 0; *p; p++, len++) 62 { 63 switch (*p) 64 { 65 case ' ': 66 case '\t': 67 /* GNU make uses a weird quoting scheme for white space. 68 A space or tab preceded by 2N+1 backslashes represents 69 N backslashes followed by space; a space or tab 70 preceded by 2N backslashes represents N backslashes at 71 the end of a file name; and backslashes in other 72 contexts should not be doubled. */ 73 for (q = p - 1; filename <= q && *q == '\\'; q--) 74 len++; 75 len++; 76 break; 77 78 case '$': 79 /* '$' is quoted by doubling it. */ 80 len++; 81 break; 82 83 case '#': 84 /* '#' is quoted with a backslash. */ 85 len++; 86 break; 87 } 88 } 89 90 /* Now we know how big to make the buffer. */ 91 buffer = XNEWVEC (char, len + 1); 92 93 for (p = filename, dst = buffer; *p; p++, dst++) 94 { 95 switch (*p) 96 { 97 case ' ': 98 case '\t': 99 for (q = p - 1; filename <= q && *q == '\\'; q--) 100 *dst++ = '\\'; 101 *dst++ = '\\'; 102 break; 103 104 case '$': 105 *dst++ = '$'; 106 break; 107 108 case '#': 109 *dst++ = '\\'; 110 break; 111 112 default: 113 /* nothing */; 114 } 115 *dst = *p; 116 } 117 118 *dst = '\0'; 119 return buffer; 120 } 121 122 /* If T begins with any of the partial pathnames listed in d->vpathv, 123 then advance T to point beyond that pathname. */ 124 static const char * 125 apply_vpath (struct deps *d, const char *t) 126 { 127 if (d->vpathv) 128 { 129 unsigned int i; 130 for (i = 0; i < d->nvpaths; i++) 131 { 132 if (!filename_ncmp (d->vpathv[i], t, d->vpathlv[i])) 133 { 134 const char *p = t + d->vpathlv[i]; 135 if (!IS_DIR_SEPARATOR (*p)) 136 goto not_this_one; 137 138 /* Do not simplify $(vpath)/../whatever. ??? Might not 139 be necessary. */ 140 if (p[1] == '.' && p[2] == '.' && IS_DIR_SEPARATOR (p[3])) 141 goto not_this_one; 142 143 /* found a match */ 144 t = t + d->vpathlv[i] + 1; 145 break; 146 } 147 not_this_one:; 148 } 149 } 150 151 /* Remove leading ./ in any case. */ 152 while (t[0] == '.' && IS_DIR_SEPARATOR (t[1])) 153 { 154 t += 2; 155 /* If we removed a leading ./, then also remove any /s after the 156 first. */ 157 while (IS_DIR_SEPARATOR (t[0])) 158 ++t; 159 } 160 161 return t; 162 } 163 164 /* Public routines. */ 165 166 struct deps * 167 deps_init (void) 168 { 169 return XCNEW (struct deps); 170 } 171 172 void 173 deps_free (struct deps *d) 174 { 175 unsigned int i; 176 177 if (d->targetv) 178 { 179 for (i = 0; i < d->ntargets; i++) 180 free ((void *) d->targetv[i]); 181 free (d->targetv); 182 } 183 184 if (d->depv) 185 { 186 for (i = 0; i < d->ndeps; i++) 187 free ((void *) d->depv[i]); 188 free (d->depv); 189 } 190 191 if (d->vpathv) 192 { 193 for (i = 0; i < d->nvpaths; i++) 194 free ((void *) d->vpathv[i]); 195 free (d->vpathv); 196 free (d->vpathlv); 197 } 198 199 free (d); 200 } 201 202 /* Adds a target T. We make a copy, so it need not be a permanent 203 string. QUOTE is true if the string should be quoted. */ 204 void 205 deps_add_target (struct deps *d, const char *t, int quote) 206 { 207 if (d->ntargets == d->targets_size) 208 { 209 d->targets_size = d->targets_size * 2 + 4; 210 d->targetv = XRESIZEVEC (const char *, d->targetv, d->targets_size); 211 } 212 213 t = apply_vpath (d, t); 214 if (quote) 215 t = munge (t); /* Also makes permanent copy. */ 216 else 217 t = xstrdup (t); 218 219 d->targetv[d->ntargets++] = t; 220 } 221 222 /* Sets the default target if none has been given already. An empty 223 string as the default target in interpreted as stdin. The string 224 is quoted for MAKE. */ 225 void 226 deps_add_default_target (struct deps *d, const char *tgt) 227 { 228 /* Only if we have no targets. */ 229 if (d->ntargets) 230 return; 231 232 if (tgt[0] == '\0') 233 deps_add_target (d, "-", 1); 234 else 235 { 236 #ifndef TARGET_OBJECT_SUFFIX 237 # define TARGET_OBJECT_SUFFIX ".o" 238 #endif 239 const char *start = lbasename (tgt); 240 char *o = (char *) alloca (strlen (start) 241 + strlen (TARGET_OBJECT_SUFFIX) + 1); 242 char *suffix; 243 244 strcpy (o, start); 245 246 suffix = strrchr (o, '.'); 247 if (!suffix) 248 suffix = o + strlen (o); 249 strcpy (suffix, TARGET_OBJECT_SUFFIX); 250 251 deps_add_target (d, o, 1); 252 } 253 } 254 255 void 256 deps_add_dep (struct deps *d, const char *t) 257 { 258 t = munge (apply_vpath (d, t)); /* Also makes permanent copy. */ 259 260 if (d->ndeps == d->deps_size) 261 { 262 d->deps_size = d->deps_size * 2 + 8; 263 d->depv = XRESIZEVEC (const char *, d->depv, d->deps_size); 264 } 265 d->depv[d->ndeps++] = t; 266 } 267 268 void 269 deps_add_vpath (struct deps *d, const char *vpath) 270 { 271 const char *elem, *p; 272 char *copy; 273 size_t len; 274 275 for (elem = vpath; *elem; elem = p) 276 { 277 for (p = elem; *p && *p != ':'; p++); 278 len = p - elem; 279 copy = XNEWVEC (char, len + 1); 280 memcpy (copy, elem, len); 281 copy[len] = '\0'; 282 if (*p == ':') 283 p++; 284 285 if (d->nvpaths == d->vpaths_size) 286 { 287 d->vpaths_size = d->vpaths_size * 2 + 8; 288 d->vpathv = XRESIZEVEC (const char *, d->vpathv, d->vpaths_size); 289 d->vpathlv = XRESIZEVEC (size_t, d->vpathlv, d->vpaths_size); 290 } 291 d->vpathv[d->nvpaths] = copy; 292 d->vpathlv[d->nvpaths] = len; 293 d->nvpaths++; 294 } 295 } 296 297 void 298 deps_write (const struct deps *d, FILE *fp, unsigned int colmax) 299 { 300 unsigned int size, i, column; 301 302 column = 0; 303 if (colmax && colmax < 34) 304 colmax = 34; 305 306 for (i = 0; i < d->ntargets; i++) 307 { 308 size = strlen (d->targetv[i]); 309 column += size; 310 if (i) 311 { 312 if (colmax && column > colmax) 313 { 314 fputs (" \\\n ", fp); 315 column = 1 + size; 316 } 317 else 318 { 319 putc (' ', fp); 320 column++; 321 } 322 } 323 fputs (d->targetv[i], fp); 324 } 325 326 putc (':', fp); 327 column++; 328 329 for (i = 0; i < d->ndeps; i++) 330 { 331 size = strlen (d->depv[i]); 332 column += size; 333 if (colmax && column > colmax) 334 { 335 fputs (" \\\n ", fp); 336 column = 1 + size; 337 } 338 else 339 { 340 putc (' ', fp); 341 column++; 342 } 343 fputs (d->depv[i], fp); 344 } 345 putc ('\n', fp); 346 } 347 348 void 349 deps_phony_targets (const struct deps *d, FILE *fp) 350 { 351 unsigned int i; 352 353 for (i = 1; i < d->ndeps; i++) 354 { 355 putc ('\n', fp); 356 fputs (d->depv[i], fp); 357 putc (':', fp); 358 putc ('\n', fp); 359 } 360 } 361 362 /* Write out a deps buffer to a file, in a form that can be read back 363 with deps_restore. Returns nonzero on error, in which case the 364 error number will be in errno. */ 365 366 int 367 deps_save (struct deps *deps, FILE *f) 368 { 369 unsigned int i; 370 371 /* The cppreader structure contains makefile dependences. Write out this 372 structure. */ 373 374 /* The number of dependences. */ 375 if (fwrite (&deps->ndeps, sizeof (deps->ndeps), 1, f) != 1) 376 return -1; 377 /* The length of each dependence followed by the string. */ 378 for (i = 0; i < deps->ndeps; i++) 379 { 380 size_t num_to_write = strlen (deps->depv[i]); 381 if (fwrite (&num_to_write, sizeof (size_t), 1, f) != 1) 382 return -1; 383 if (fwrite (deps->depv[i], num_to_write, 1, f) != 1) 384 return -1; 385 } 386 387 return 0; 388 } 389 390 /* Read back dependency information written with deps_save into 391 the deps buffer. The third argument may be NULL, in which case 392 the dependency information is just skipped, or it may be a filename, 393 in which case that filename is skipped. */ 394 395 int 396 deps_restore (struct deps *deps, FILE *fd, const char *self) 397 { 398 unsigned int i, count; 399 size_t num_to_read; 400 size_t buf_size = 512; 401 char *buf; 402 403 /* Number of dependences. */ 404 if (fread (&count, 1, sizeof (count), fd) != sizeof (count)) 405 return -1; 406 407 buf = XNEWVEC (char, buf_size); 408 409 /* The length of each dependence string, followed by the string. */ 410 for (i = 0; i < count; i++) 411 { 412 /* Read in # bytes in string. */ 413 if (fread (&num_to_read, 1, sizeof (size_t), fd) != sizeof (size_t)) 414 { 415 free (buf); 416 return -1; 417 } 418 if (buf_size < num_to_read + 1) 419 { 420 buf_size = num_to_read + 1 + 127; 421 buf = XRESIZEVEC (char, buf, buf_size); 422 } 423 if (fread (buf, 1, num_to_read, fd) != num_to_read) 424 { 425 free (buf); 426 return -1; 427 } 428 buf[num_to_read] = '\0'; 429 430 /* Generate makefile dependencies from .pch if -nopch-deps. */ 431 if (self != NULL && filename_cmp (buf, self) != 0) 432 deps_add_dep (deps, buf); 433 } 434 435 free (buf); 436 return 0; 437 } 438