[thirdparty/gcc.git] / libcpp / mkdeps.c

/* Dependency generator for Makefile fragments.
   Copyright (C) 2000, 2001, 2003, 2007 Free Software Foundation, Inc.
   Contributed by Zack Weinberg, Mar 2000

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 In other words, you are welcome to use, share and improve this program.
 You are forbidden to forbid anyone else to use, share and improve
 what you give them.   Help stamp out software-hoarding!  */

#include "config.h"
#include "system.h"
#include "mkdeps.h"

/* Keep this structure local to this file, so clients don't find it
   easy to start making assumptions.  */
struct deps
{
  const char **targetv;
  unsigned int ntargets;	/* number of slots actually occupied */
  unsigned int targets_size;	/* amt of allocated space - in words */

  const char **depv;
  unsigned int ndeps;
  unsigned int deps_size;

  const char **vpathv;
  size_t *vpathlv;
  unsigned int nvpaths;
  unsigned int vpaths_size;
};

static const char *munge (const char *);

/* Given a filename, quote characters in that filename which are
   significant to Make.  Note that it's not possible to quote all such
   characters - e.g. \n, %, *, ?, [, \ (in some contexts), and ~ are
   not properly handled.  It isn't possible to get this right in any
   current version of Make.  (??? Still true?  Old comment referred to
   3.76.1.)  */

static const char *
munge (const char *filename)
{
  int len;
  const char *p, *q;
  char *dst, *buffer;

  for (p = filename, len = 0; *p; p++, len++)
    {
      switch (*p)
	{
	case ' ':
	case '\t':
	  /* GNU make uses a weird quoting scheme for white space.
	     A space or tab preceded by 2N+1 backslashes represents
	     N backslashes followed by space; a space or tab
	     preceded by 2N backslashes represents N backslashes at
	     the end of a file name; and backslashes in other
	     contexts should not be doubled.  */
	  for (q = p - 1; filename <= q && *q == '\\';  q--)
	    len++;
	  len++;
	  break;

	case '$':
	  /* '$' is quoted by doubling it.  */
	  len++;
	  break;
	}
    }

  /* Now we know how big to make the buffer.  */
  buffer = XNEWVEC (char, len + 1);

  for (p = filename, dst = buffer; *p; p++, dst++)
    {
      switch (*p)
	{
	case ' ':
	case '\t':
	  for (q = p - 1; filename <= q && *q == '\\';  q--)
	    *dst++ = '\\';
	  *dst++ = '\\';
	  break;

	case '$':
	  *dst++ = '$';
	  break;

	default:
	  /* nothing */;
	}
      *dst = *p;
    }

  *dst = '\0';
  return buffer;
}

/* If T begins with any of the partial pathnames listed in d->vpathv,
   then advance T to point beyond that pathname.  */
static const char *
apply_vpath (struct deps *d, const char *t)
{
  if (d->vpathv)
    {
      unsigned int i;
      for (i = 0; i < d->nvpaths; i++)
	{
	  if (!strncmp (d->vpathv[i], t, d->vpathlv[i]))
	    {
	      const char *p = t + d->vpathlv[i];
	      if (!IS_DIR_SEPARATOR (*p))
		goto not_this_one;

	      /* Do not simplify $(vpath)/../whatever.  ??? Might not
		 be necessary. */
	      if (p[1] == '.' && p[2] == '.' && IS_DIR_SEPARATOR (p[3]))
		goto not_this_one;

	      /* found a match */
	      t = t + d->vpathlv[i] + 1;
	      break;
	    }
	not_this_one:;
	}
    }

  /* Remove leading ./ in any case.  */
  while (t[0] == '.' && IS_DIR_SEPARATOR (t[1]))
    {
      t += 2;
      /* If we removed a leading ./, then also remove any /s after the
	 first.  */
      while (IS_DIR_SEPARATOR (t[0]))
	++t;
    }

  return t;
}

/* Public routines.  */

struct deps *
deps_init (void)
{
  return XCNEW (struct deps);
}

void
deps_free (struct deps *d)
{
  unsigned int i;

  if (d->targetv)
    {
      for (i = 0; i < d->ntargets; i++)
	free ((void *) d->targetv[i]);
      free (d->targetv);
    }

  if (d->depv)
    {
      for (i = 0; i < d->ndeps; i++)
	free ((void *) d->depv[i]);
      free (d->depv);
    }

  if (d->vpathv)
    {
      for (i = 0; i < d->nvpaths; i++)
	free ((void *) d->vpathv[i]);
      free (d->vpathv);
      free (d->vpathlv);
    }

  free (d);
}

/* Adds a target T.  We make a copy, so it need not be a permanent
   string.  QUOTE is true if the string should be quoted.  */
void
deps_add_target (struct deps *d, const char *t, int quote)
{
  if (d->ntargets == d->targets_size)
    {
      d->targets_size = d->targets_size * 2 + 4;
      d->targetv = XRESIZEVEC (const char *, d->targetv, d->targets_size);
    }

  t = apply_vpath (d, t);
  if (quote)
    t = munge (t);  /* Also makes permanent copy.  */
  else
    t = xstrdup (t);

  d->targetv[d->ntargets++] = t;
}

/* Sets the default target if none has been given already.  An empty
   string as the default target in interpreted as stdin.  The string
   is quoted for MAKE.  */
void
deps_add_default_target (struct deps *d, const char *tgt)
{
  /* Only if we have no targets.  */
  if (d->ntargets)
    return;

  if (tgt[0] == '\0')
    deps_add_target (d, "-", 1);
  else
    {
#ifndef TARGET_OBJECT_SUFFIX
# define TARGET_OBJECT_SUFFIX ".o"
#endif
      const char *start = lbasename (tgt);
      char *o = (char *) alloca (strlen (start)
                                 + strlen (TARGET_OBJECT_SUFFIX) + 1);
      char *suffix;

      strcpy (o, start);

      suffix = strrchr (o, '.');
      if (!suffix)
        suffix = o + strlen (o);
      strcpy (suffix, TARGET_OBJECT_SUFFIX);

      deps_add_target (d, o, 1);
    }
}

void
deps_add_dep (struct deps *d, const char *t)
{
  t = munge (apply_vpath (d, t));  /* Also makes permanent copy.  */

  if (d->ndeps == d->deps_size)
    {
      d->deps_size = d->deps_size * 2 + 8;
      d->depv = XRESIZEVEC (const char *, d->depv, d->deps_size);
    }
  d->depv[d->ndeps++] = t;
}

void
deps_add_vpath (struct deps *d, const char *vpath)
{
  const char *elem, *p;
  char *copy;
  size_t len;

  for (elem = vpath; *elem; elem = p)
    {
      for (p = elem; *p && *p != ':'; p++);
      len = p - elem;
      copy = XNEWVEC (char, len + 1);
      memcpy (copy, elem, len);
      copy[len] = '\0';
      if (*p == ':')
	p++;

      if (d->nvpaths == d->vpaths_size)
	{
	  d->vpaths_size = d->vpaths_size * 2 + 8;
	  d->vpathv = XRESIZEVEC (const char *, d->vpathv, d->vpaths_size);
	  d->vpathlv = XRESIZEVEC (size_t, d->vpathlv, d->vpaths_size);
	}
      d->vpathv[d->nvpaths] = copy;
      d->vpathlv[d->nvpaths] = len;
      d->nvpaths++;
    }
}

void
deps_write (const struct deps *d, FILE *fp, unsigned int colmax)
{
  unsigned int size, i, column;

  column = 0;
  if (colmax && colmax < 34)
    colmax = 34;

  for (i = 0; i < d->ntargets; i++)
    {
      size = strlen (d->targetv[i]);
      column += size;
      if (colmax && column > colmax)
	{
	  fputs (" \\\n ", fp);
	  column = 1 + size;
	}
      if (i)
	{
	  putc (' ', fp);
	  column++;
	}
      fputs (d->targetv[i], fp);
    }

  putc (':', fp);
  putc (' ', fp);
  column += 2;

  for (i = 0; i < d->ndeps; i++)
    {
      size = strlen (d->depv[i]);
      column += size;
      if (colmax && column > colmax)
	{
	  fputs (" \\\n ", fp);
	  column = 1 + size;
	}
      if (i)
	{
	  putc (' ', fp);
	  column++;
	}
      fputs (d->depv[i], fp);
    }
  putc ('\n', fp);
}

void
deps_phony_targets (const struct deps *d, FILE *fp)
{
  unsigned int i;

  for (i = 1; i < d->ndeps; i++)
    {
      putc ('\n', fp);
      fputs (d->depv[i], fp);
      putc (':', fp);
      putc ('\n', fp);
    }
}

/* Write out a deps buffer to a file, in a form that can be read back
   with deps_restore.  Returns nonzero on error, in which case the
   error number will be in errno.  */

int
deps_save (struct deps *deps, FILE *f)
{
  unsigned int i;

  /* The cppreader structure contains makefile dependences.  Write out this
     structure.  */

  /* The number of dependences.  */
  if (fwrite (&deps->ndeps, sizeof (deps->ndeps), 1, f) != 1)
      return -1;
  /* The length of each dependence followed by the string.  */
  for (i = 0; i < deps->ndeps; i++)
    {
      size_t num_to_write = strlen (deps->depv[i]);
      if (fwrite (&num_to_write, sizeof (size_t), 1, f) != 1)
          return -1;
      if (fwrite (deps->depv[i], num_to_write, 1, f) != 1)
          return -1;
    }

  return 0;
}

/* Read back dependency information written with deps_save into
   the deps buffer.  The third argument may be NULL, in which case
   the dependency information is just skipped, or it may be a filename,
   in which case that filename is skipped.  */

int
deps_restore (struct deps *deps, FILE *fd, const char *self)
{
  unsigned int i, count;
  size_t num_to_read;
  size_t buf_size = 512;
  char *buf = XNEWVEC (char, buf_size);

  /* Number of dependences.  */
  if (fread (&count, 1, sizeof (count), fd) != sizeof (count))
    return -1;

  /* The length of each dependence string, followed by the string.  */
  for (i = 0; i < count; i++)
    {
      /* Read in # bytes in string.  */
      if (fread (&num_to_read, 1, sizeof (size_t), fd) != sizeof (size_t))
	return -1;
      if (buf_size < num_to_read + 1)
	{
	  buf_size = num_to_read + 1 + 127;
	  buf = XRESIZEVEC (char, buf, buf_size);
	}
      if (fread (buf, 1, num_to_read, fd) != num_to_read)
	return -1;
      buf[num_to_read] = '\0';

      /* Generate makefile dependencies from .pch if -nopch-deps.  */
      if (self != NULL && strcmp (buf, self) != 0)
        deps_add_dep (deps, buf);
    }

  free (buf);
  return 0;
}
Commit	Line	Data
49e6c08e	1	/* Dependency generator for Makefile fragments.
67e64439	2	Copyright (C) 2000, 2001, 2003, 2007 Free Software Foundation, Inc.
49e6c08e ZW	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
200031d1	17	Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
49e6c08e ZW	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
03b9ab42 NB	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;
c6e83800 ZW	38
	39	const char **vpathv;
	40	size_t *vpathlv;
	41	unsigned int nvpaths;
	42	unsigned int vpaths_size;
03b9ab42 NB	43	};
03b9ab42 NB	44
0c20a65f	45	static const char munge (const char );
49e6c08e	46
49e6c08e ZW	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.) */
0c20a65f	53
49e6c08e	54	static const char *
0c20a65f	55	munge (const char *filename)
49e6c08e ZW	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. */
e23c0ba3	73	for (q = p - 1; filename <= q && *q == '\\'; q--)
49e6c08e ZW	74	len++;
	75	len++;
	76	break;
	77
	78	case '$':
a5a4ce3c	79	/* '$' is quoted by doubling it. */
49e6c08e ZW	80	len++;
	81	break;
	82	}
	83	}
	84
	85	/* Now we know how big to make the buffer. */
c3f829c1	86	buffer = XNEWVEC (char, len + 1);
49e6c08e ZW	87
	88	for (p = filename, dst = buffer; *p; p++, dst++)
	89	{
	90	switch (*p)
	91	{
	92	case ' ':
	93	case '\t':
e23c0ba3	94	for (q = p - 1; filename <= q && *q == '\\'; q--)
49e6c08e ZW	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
c6e83800 ZW	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)
49e6c08e	117	{
c6e83800 ZW	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	}
49e6c08e	141
c6e83800 ZW	142	/* Remove leading ./ in any case. */
c6e83800 ZW	143	while (t[0] == '.' && IS_DIR_SEPARATOR (t[1]))
67e64439 TT	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	}
49e6c08e	151
c6e83800 ZW	152	return t;
c6e83800 ZW	153	}
49e6c08e	154
c6e83800	155	/* Public routines. */
49e6c08e	156
c6e83800 ZW	157	struct deps *
	158	deps_init (void)
	159	{
c3f829c1	160	return XCNEW (struct deps);
49e6c08e ZW	161	}
	162
	163	void
0c20a65f	164	deps_free (struct deps *d)
49e6c08e ZW	165	{
49e6c08e ZW	166	unsigned int i;
05bccae2	167
f7114e17 NB	168	if (d->targetv)
	169	{
	170	for (i = 0; i < d->ntargets; i++)
fad205ff	171	free ((void *) d->targetv[i]);
f7114e17 NB	172	free (d->targetv);
f7114e17 NB	173	}
05bccae2	174
f7114e17 NB	175	if (d->depv)
	176	{
	177	for (i = 0; i < d->ndeps; i++)
fad205ff	178	free ((void *) d->depv[i]);
f7114e17 NB	179	free (d->depv);
f7114e17 NB	180	}
49e6c08e	181
c6e83800 ZW	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
49e6c08e ZW	190	free (d);
	191	}
	192
a5a4ce3c NB	193	/* Adds a target T. We make a copy, so it need not be a permanent
a5a4ce3c NB	194	string. QUOTE is true if the string should be quoted. */
49e6c08e	195	void
0c20a65f	196	deps_add_target (struct deps d, const char t, int quote)
49e6c08e	197	{
49e6c08e ZW	198	if (d->ntargets == d->targets_size)
49e6c08e ZW	199	{
f7114e17	200	d->targets_size = d->targets_size * 2 + 4;
c3f829c1	201	d->targetv = XRESIZEVEC (const char *, d->targetv, d->targets_size);
49e6c08e	202	}
05bccae2	203
c6e83800	204	t = apply_vpath (d, t);
a5a4ce3c NB	205	if (quote)
	206	t = munge (t); /* Also makes permanent copy. */
	207	else
	208	t = xstrdup (t);
	209
49e6c08e ZW	210	d->targetv[d->ntargets++] = t;
	211	}
	212
03b9ab42	213	/* Sets the default target if none has been given already. An empty
a5a4ce3c NB	214	string as the default target in interpreted as stdin. The string
a5a4ce3c NB	215	is quoted for MAKE. */
49e6c08e	216	void
0c20a65f	217	deps_add_default_target (struct deps d, const char tgt)
49e6c08e	218	{
03b9ab42 NB	219	/* Only if we have no targets. */
	220	if (d->ntargets)
	221	return;
49e6c08e	222
03b9ab42	223	if (tgt[0] == '\0')
a5a4ce3c	224	deps_add_target (d, "-", 1);
49e6c08e	225	else
03b9ab42	226	{
45936a85 DD	227	#ifndef TARGET_OBJECT_SUFFIX
45936a85 DD	228	# define TARGET_OBJECT_SUFFIX ".o"
03b9ab42	229	#endif
0821bff7	230	const char *start = lbasename (tgt);
c3f829c1 GDR	231	char o = (char ) alloca (strlen (start)
c3f829c1 GDR	232	+ strlen (TARGET_OBJECT_SUFFIX) + 1);
48ce6bbb	233	char *suffix;
03b9ab42	234
48ce6bbb	235	strcpy (o, start);
0c20a65f	236
48ce6bbb NS	237	suffix = strrchr (o, '.');
	238	if (!suffix)
	239	suffix = o + strlen (o);
45936a85	240	strcpy (suffix, TARGET_OBJECT_SUFFIX);
0c20a65f	241
a5a4ce3c	242	deps_add_target (d, o, 1);
03b9ab42	243	}
49e6c08e ZW	244	}
	245
	246	void
0c20a65f	247	deps_add_dep (struct deps d, const char t)
49e6c08e	248	{
c6e83800	249	t = munge (apply_vpath (d, t)); /* Also makes permanent copy. */
49e6c08e ZW	250
	251	if (d->ndeps == d->deps_size)
	252	{
fa6f74f6	253	d->deps_size = d->deps_size * 2 + 8;
c3f829c1	254	d->depv = XRESIZEVEC (const char *, d->depv, d->deps_size);
49e6c08e ZW	255	}
	256	d->depv[d->ndeps++] = t;
	257	}
	258
c6e83800 ZW	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;
c3f829c1	270	copy = XNEWVEC (char, len + 1);
c6e83800 ZW	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;
c3f829c1 GDR	279	d->vpathv = XRESIZEVEC (const char *, d->vpathv, d->vpaths_size);
c3f829c1 GDR	280	d->vpathlv = XRESIZEVEC (size_t, d->vpathlv, d->vpaths_size);
c6e83800 ZW	281	}
	282	d->vpathv[d->nvpaths] = copy;
	283	d->vpathlv[d->nvpaths] = len;
	284	d->nvpaths++;
	285	}
	286	}
	287
49e6c08e	288	void
0c20a65f	289	deps_write (const struct deps d, FILE fp, unsigned int colmax)
49e6c08e ZW	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	}
0c20a65f	336
49e6c08e	337	void
0c20a65f	338	deps_phony_targets (const struct deps d, FILE fp)
49e6c08e	339	{
05bccae2	340	unsigned int i;
49e6c08e ZW	341
	342	for (i = 1; i < d->ndeps; i++)
	343	{
a5a4ce3c	344	putc ('\n', fp);
49e6c08e ZW	345	fputs (d->depv[i], fp);
	346	putc (':', fp);
	347	putc ('\n', fp);
	348	}
	349	}
17211ab5 GK	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
0c20a65f	356	deps_save (struct deps deps, FILE f)
17211ab5 GK	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
0c20a65f	385	deps_restore (struct deps deps, FILE fd, const char *self)
17211ab5 GK	386	{
	387	unsigned int i, count;
	388	size_t num_to_read;
	389	size_t buf_size = 512;
c3f829c1	390	char *buf = XNEWVEC (char, buf_size);
17211ab5 GK	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;
c3f829c1	405	buf = XRESIZEVEC (char, buf, buf_size);
17211ab5 GK	406	}
	407	if (fread (buf, 1, num_to_read, fd) != num_to_read)
	408	return -1;
	409	buf[num_to_read] = '\0';
	410
0c20a65f	411	/* Generate makefile dependencies from .pch if -nopch-deps. */
17211ab5 GK	412	if (self != NULL && strcmp (buf, self) != 0)
	413	deps_add_dep (deps, buf);
	414	}
	415
	416	free (buf);
	417	return 0;
	418	}