/* Dependency generator for Makefile fragments.
Copyright (C) 2000-2019 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 3, 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; see the file COPYING3. If not see
.
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"
/* Not set up to just include std::vector et al, here's a simple
implementation. */
/* Keep this structure local to this file, so clients don't find it
easy to start making assumptions. */
struct mkdeps
{
public:
/* T has trivial cctor & dtor. */
template
class vec
{
private:
T *ary;
unsigned num;
unsigned alloc;
public:
vec ()
: ary (NULL), num (0), alloc (0)
{}
~vec ()
{
XDELETEVEC (ary);
}
public:
unsigned size () const
{
return num;
}
const T &operator[] (unsigned ix) const
{
return ary[ix];
}
T &operator[] (unsigned ix)
{
return ary[ix];
}
void push (const T &elt)
{
if (num == alloc)
{
alloc = alloc ? alloc * 2 : 16;
ary = XRESIZEVEC (T, ary, alloc);
}
ary[num++] = elt;
}
};
struct velt
{
const char *str;
size_t len;
};
mkdeps ()
: quote_lwm (0)
{
}
~mkdeps ()
{
unsigned int i;
for (i = targets.size (); i--;)
free (const_cast (targets[i]));
for (i = deps.size (); i--;)
free (const_cast (deps[i]));
for (i = vpath.size (); i--;)
XDELETEVEC (vpath[i].str);
}
public:
vec targets;
vec deps;
vec vpath;
public:
unsigned short quote_lwm;
};
/* Apply Make quoting to STR, TRAIL etc. 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 *str, const char *trail = NULL, ...)
{
static unsigned alloc;
static char *buf;
unsigned dst = 0;
va_list args;
if (trail)
va_start (args, trail);
for (bool first = true; str; first = false)
{
unsigned slashes = 0;
char c;
for (const char *probe = str; (c = *probe++);)
{
if (alloc < dst + 4 + slashes)
{
alloc = alloc * 2 + 32;
buf = XRESIZEVEC (char, buf, alloc);
}
switch (c)
{
case '\\':
slashes++;
break;
case '$':
buf[dst++] = '$';
goto def;
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. */
while (slashes--)
buf[dst++] = '\\';
/* FALLTHROUGH */
case '#':
case ':':
buf[dst++] = '\\';
/* FALLTHROUGH */
default:
def:
slashes = 0;
break;
}
buf[dst++] = c;
}
if (first)
str = trail;
else
str = va_arg (args, const char *);
}
if (trail)
va_end (args);
buf[dst] = 0;
return buf;
}
/* 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 mkdeps *d, const char *t)
{
if (unsigned len = d->vpath.size ())
for (unsigned i = len; i--;)
{
if (!filename_ncmp (d->vpath[i].str, t, d->vpath[i].len))
{
const char *p = t + d->vpath[i].len;
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->vpath[i].len + 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 mkdeps *
deps_init (void)
{
return new mkdeps ();
}
void
deps_free (struct mkdeps *d)
{
delete 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 mkdeps *d, const char *t, int quote)
{
t = xstrdup (apply_vpath (d, t));
if (!quote)
{
/* Sometimes unquoted items are added after quoted ones.
Swap out the lowest quoted. */
if (d->quote_lwm != d->targets.size ())
{
const char *lowest = d->targets[d->quote_lwm];
d->targets[d->quote_lwm] = t;
t = lowest;
}
d->quote_lwm++;
}
d->targets.push (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 mkdeps *d, const char *tgt)
{
/* Only if we have no targets. */
if (d->targets.size ())
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 mkdeps *d, const char *t)
{
gcc_assert (*t);
t = apply_vpath (d, t);
d->deps.push (xstrdup (t));
}
void
deps_add_vpath (struct mkdeps *d, const char *vpath)
{
const char *elem, *p;
for (elem = vpath; *elem; elem = p)
{
for (p = elem; *p && *p != ':'; p++)
continue;
mkdeps::velt elt;
elt.len = p - elem;
char *str = XNEWVEC (char, elt.len + 1);
elt.str = str;
memcpy (str, elem, elt.len);
str[elt.len] = '\0';
if (*p == ':')
p++;
d->vpath.push (elt);
}
}
/* Write NAME, with a leading space to FP, a Makefile. Advance COL as
appropriate, wrap at COLMAX, returning new column number. Iff
QUOTE apply quoting. Append TRAIL. */
static unsigned
make_write_name (const char *name, FILE *fp, unsigned col, unsigned colmax,
bool quote = true, const char *trail = NULL)
{
if (quote)
name = munge (name, trail, NULL);
unsigned size = strlen (name);
if (col)
{
if (colmax && col + size> colmax)
{
fputs (" \\\n", fp);
col = 0;
}
col++;
fputs (" ", fp);
}
col += size;
fputs (name, fp);
return col;
}
/* Write all the names in VEC via make_write_name. */
static unsigned
make_write_vec (const mkdeps::vec &vec, FILE *fp,
unsigned col, unsigned colmax, unsigned quote_lwm = 0,
const char *trail = NULL)
{
for (unsigned ix = 0; ix != vec.size (); ix++)
col = make_write_name (vec[ix], fp, col, colmax, ix >= quote_lwm, trail);
return col;
}
/* Write the dependencies to a Makefile. If PHONY is true, add
.PHONY targets for all the dependencies too. */
static void
make_write (const struct mkdeps *d, FILE *fp, bool phony, unsigned int colmax)
{
unsigned column = 0;
if (colmax && colmax < 34)
colmax = 34;
if (d->deps.size ())
{
column = make_write_vec (d->targets, fp, 0, colmax, d->quote_lwm);
fputs (":", fp);
column++;
column = make_write_vec (d->deps, fp, column, colmax);
fputs ("\n", fp);
if (phony)
for (unsigned i = 1; i < d->deps.size (); i++)
fprintf (fp, "%s:\n", munge (d->deps[i]));
}
}
/* Write out dependencies according to the selected format (which is
only Make at the moment). */
void
deps_write (const struct mkdeps *d, FILE *fp, bool phony, unsigned int colmax)
{
make_write (d, fp, phony, colmax);
}
/* 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 mkdeps *deps, FILE *f)
{
unsigned int i;
size_t size;
/* The cppreader structure contains makefile dependences. Write out this
structure. */
/* The number of dependences. */
size = deps->deps.size ();
if (fwrite (&size, sizeof (size), 1, f) != 1)
return -1;
/* The length of each dependence followed by the string. */
for (i = 0; i < deps->deps.size (); i++)
{
size = strlen (deps->deps[i]);
if (fwrite (&size, sizeof (size), 1, f) != 1)
return -1;
if (fwrite (deps->deps[i], size, 1, f) != 1)
return -1;
}
return 0;
}
/* Read back dependency information written with deps_save into
the deps sizefer. 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 mkdeps *deps, FILE *fd, const char *self)
{
size_t size;
char *buf = NULL;
size_t buf_size = 0;
/* Number of dependences. */
if (fread (&size, sizeof (size), 1, fd) != 1)
return -1;
/* The length of each dependence string, followed by the string. */
for (unsigned i = size; i--;)
{
/* Read in # bytes in string. */
if (fread (&size, sizeof (size), 1, fd) != 1)
return -1;
if (size >= buf_size)
{
buf_size = size + 512;
buf = XRESIZEVEC (char, buf, buf_size);
}
if (fread (buf, 1, size, fd) != size)
{
XDELETEVEC (buf);
return -1;
}
buf[size] = 0;
/* Generate makefile dependencies from .pch if -nopch-deps. */
if (self != NULL && filename_cmp (buf, self) != 0)
deps_add_dep (deps, buf);
}
XDELETEVEC (buf);
return 0;
}