1 /* Dependency generator for Makefile fragments. 2 Copyright (C) 2000, 2001, 2003, 2007 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 2, 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; if not, write to the Free Software 17 Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 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 } 84 85 /* Now we know how big to make the buffer. */ 86 buffer = XNEWVEC (char, len + 1); 87 88 for (p = filename, dst = buffer; *p; p++, dst++) 89 { 90 switch (*p) 91 { 92 case ' ': 93 case '\t': 94 for (q = p - 1; filename <= q && *q == '\\'; q--) 95 *dst++ = '\\'; 96 *dst++ = '\\'; 97 break; 98 99 case '$': 100 *dst++ = '$'; 101 break; 102 103 default: 104 /* nothing */; 105 } 106 *dst = *p; 107 } 108 109 *dst = '\0'; 110 return buffer; 111 } 112 113 /* If T begins with any of the partial pathnames listed in d->vpathv, 114 then advance T to point beyond that pathname. */ 115 static const char * 116 apply_vpath (struct deps *d, const char *t) 117 { 118 if (d->vpathv) 119 { 120 unsigned int i; 121 for (i = 0; i < d->nvpaths; i++) 122 { 123 if (!strncmp (d->vpathv[i], t, d->vpathlv[i])) 124 { 125 const char *p = t + d->vpathlv[i]; 126 if (!IS_DIR_SEPARATOR (*p)) 127 goto not_this_one; 128 129 /* Do not simplify $(vpath)/../whatever. ??? Might not 130 be necessary. */ 131 if (p[1] == '.' && p[2] == '.' && IS_DIR_SEPARATOR (p[3])) 132 goto not_this_one; 133 134 /* found a match */ 135 t = t + d->vpathlv[i] + 1; 136 break; 137 } 138 not_this_one:; 139 } 140 } 141 142 /* Remove leading ./ in any case. */ 143 while (t[0] == '.' && IS_DIR_SEPARATOR (t[1])) 144 { 145 t += 2; 146 /* If we removed a leading ./, then also remove any /s after the 147 first. */ 148 while (IS_DIR_SEPARATOR (t[0])) 149 ++t; 150 } 151 152 return t; 153 } 154 155 /* Public routines. */ 156 157 struct deps * 158 deps_init (void) 159 { 160 return XCNEW (struct deps); 161 } 162 163 void 164 deps_free (struct deps *d) 165 { 166 unsigned int i; 167 168 if (d->targetv) 169 { 170 for (i = 0; i < d->ntargets; i++) 171 free ((void *) d->targetv[i]); 172 free (d->targetv); 173 } 174 175 if (d->depv) 176 { 177 for (i = 0; i < d->ndeps; i++) 178 free ((void *) d->depv[i]); 179 free (d->depv); 180 } 181 182 if (d->vpathv) 183 { 184 for (i = 0; i < d->nvpaths; i++) 185 free ((void *) d->vpathv[i]); 186 free (d->vpathv); 187 free (d->vpathlv); 188 } 189 190 free (d); 191 } 192 193 /* Adds a target T. We make a copy, so it need not be a permanent 194 string. QUOTE is true if the string should be quoted. */ 195 void 196 deps_add_target (struct deps *d, const char *t, int quote) 197 { 198 if (d->ntargets == d->targets_size) 199 { 200 d->targets_size = d->targets_size * 2 + 4; 201 d->targetv = XRESIZEVEC (const char *, d->targetv, d->targets_size); 202 } 203 204 t = apply_vpath (d, t); 205 if (quote) 206 t = munge (t); /* Also makes permanent copy. */ 207 else 208 t = xstrdup (t); 209 210 d->targetv[d->ntargets++] = t; 211 } 212 213 /* Sets the default target if none has been given already. An empty 214 string as the default target in interpreted as stdin. The string 215 is quoted for MAKE. */ 216 void 217 deps_add_default_target (struct deps *d, const char *tgt) 218 { 219 /* Only if we have no targets. */ 220 if (d->ntargets) 221 return; 222 223 if (tgt[0] == '\0') 224 deps_add_target (d, "-", 1); 225 else 226 { 227 #ifndef TARGET_OBJECT_SUFFIX 228 # define TARGET_OBJECT_SUFFIX ".o" 229 #endif 230 const char *start = lbasename (tgt); 231 char *o = (char *) alloca (strlen (start) 232 + strlen (TARGET_OBJECT_SUFFIX) + 1); 233 char *suffix; 234 235 strcpy (o, start); 236 237 suffix = strrchr (o, '.'); 238 if (!suffix) 239 suffix = o + strlen (o); 240 strcpy (suffix, TARGET_OBJECT_SUFFIX); 241 242 deps_add_target (d, o, 1); 243 } 244 } 245 246 void 247 deps_add_dep (struct deps *d, const char *t) 248 { 249 t = munge (apply_vpath (d, t)); /* Also makes permanent copy. */ 250 251 if (d->ndeps == d->deps_size) 252 { 253 d->deps_size = d->deps_size * 2 + 8; 254 d->depv = XRESIZEVEC (const char *, d->depv, d->deps_size); 255 } 256 d->depv[d->ndeps++] = t; 257 } 258 259 void 260 deps_add_vpath (struct deps *d, const char *vpath) 261 { 262 const char *elem, *p; 263 char *copy; 264 size_t len; 265 266 for (elem = vpath; *elem; elem = p) 267 { 268 for (p = elem; *p && *p != ':'; p++); 269 len = p - elem; 270 copy = XNEWVEC (char, len + 1); 271 memcpy (copy, elem, len); 272 copy[len] = '\0'; 273 if (*p == ':') 274 p++; 275 276 if (d->nvpaths == d->vpaths_size) 277 { 278 d->vpaths_size = d->vpaths_size * 2 + 8; 279 d->vpathv = XRESIZEVEC (const char *, d->vpathv, d->vpaths_size); 280 d->vpathlv = XRESIZEVEC (size_t, d->vpathlv, d->vpaths_size); 281 } 282 d->vpathv[d->nvpaths] = copy; 283 d->vpathlv[d->nvpaths] = len; 284 d->nvpaths++; 285 } 286 } 287 288 void 289 deps_write (const struct deps *d, FILE *fp, unsigned int colmax) 290 { 291 unsigned int size, i, column; 292 293 column = 0; 294 if (colmax && colmax < 34) 295 colmax = 34; 296 297 for (i = 0; i < d->ntargets; i++) 298 { 299 size = strlen (d->targetv[i]); 300 column += size; 301 if (colmax && column > colmax) 302 { 303 fputs (" \\\n ", fp); 304 column = 1 + size; 305 } 306 if (i) 307 { 308 putc (' ', fp); 309 column++; 310 } 311 fputs (d->targetv[i], fp); 312 } 313 314 putc (':', fp); 315 putc (' ', fp); 316 column += 2; 317 318 for (i = 0; i < d->ndeps; i++) 319 { 320 size = strlen (d->depv[i]); 321 column += size; 322 if (colmax && column > colmax) 323 { 324 fputs (" \\\n ", fp); 325 column = 1 + size; 326 } 327 if (i) 328 { 329 putc (' ', fp); 330 column++; 331 } 332 fputs (d->depv[i], fp); 333 } 334 putc ('\n', fp); 335 } 336 337 void 338 deps_phony_targets (const struct deps *d, FILE *fp) 339 { 340 unsigned int i; 341 342 for (i = 1; i < d->ndeps; i++) 343 { 344 putc ('\n', fp); 345 fputs (d->depv[i], fp); 346 putc (':', fp); 347 putc ('\n', fp); 348 } 349 } 350 351 /* Write out a deps buffer to a file, in a form that can be read back 352 with deps_restore. Returns nonzero on error, in which case the 353 error number will be in errno. */ 354 355 int 356 deps_save (struct deps *deps, FILE *f) 357 { 358 unsigned int i; 359 360 /* The cppreader structure contains makefile dependences. Write out this 361 structure. */ 362 363 /* The number of dependences. */ 364 if (fwrite (&deps->ndeps, sizeof (deps->ndeps), 1, f) != 1) 365 return -1; 366 /* The length of each dependence followed by the string. */ 367 for (i = 0; i < deps->ndeps; i++) 368 { 369 size_t num_to_write = strlen (deps->depv[i]); 370 if (fwrite (&num_to_write, sizeof (size_t), 1, f) != 1) 371 return -1; 372 if (fwrite (deps->depv[i], num_to_write, 1, f) != 1) 373 return -1; 374 } 375 376 return 0; 377 } 378 379 /* Read back dependency information written with deps_save into 380 the deps buffer. The third argument may be NULL, in which case 381 the dependency information is just skipped, or it may be a filename, 382 in which case that filename is skipped. */ 383 384 int 385 deps_restore (struct deps *deps, FILE *fd, const char *self) 386 { 387 unsigned int i, count; 388 size_t num_to_read; 389 size_t buf_size = 512; 390 char *buf = XNEWVEC (char, buf_size); 391 392 /* Number of dependences. */ 393 if (fread (&count, 1, sizeof (count), fd) != sizeof (count)) 394 return -1; 395 396 /* The length of each dependence string, followed by the string. */ 397 for (i = 0; i < count; i++) 398 { 399 /* Read in # bytes in string. */ 400 if (fread (&num_to_read, 1, sizeof (size_t), fd) != sizeof (size_t)) 401 return -1; 402 if (buf_size < num_to_read + 1) 403 { 404 buf_size = num_to_read + 1 + 127; 405 buf = XRESIZEVEC (char, buf, buf_size); 406 } 407 if (fread (buf, 1, num_to_read, fd) != num_to_read) 408 return -1; 409 buf[num_to_read] = '\0'; 410 411 /* Generate makefile dependencies from .pch if -nopch-deps. */ 412 if (self != NULL && strcmp (buf, self) != 0) 413 deps_add_dep (deps, buf); 414 } 415 416 free (buf); 417 return 0; 418 } 419