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 *
munge(const char * filename)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 *
apply_vpath(struct deps * d,const char * t)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 *
deps_init(void)158 deps_init (void)
159 {
160 return XCNEW (struct deps);
161 }
162
163 void
deps_free(struct deps * d)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
deps_add_target(struct deps * d,const char * t,int quote)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
deps_add_default_target(struct deps * d,const char * tgt)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
deps_add_dep(struct deps * d,const char * t)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
deps_add_vpath(struct deps * d,const char * vpath)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
deps_write(const struct deps * d,FILE * fp,unsigned int colmax)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
deps_phony_targets(const struct deps * d,FILE * fp)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
deps_save(struct deps * deps,FILE * f)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
deps_restore(struct deps * deps,FILE * fd,const char * self)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