Imported GNU Make 3.81upstream/3.82upstream

1 files changed, 605 insertions, 0 deletions

diff --git a/expand.c b/expand.c
new file mode 100644
index 0000000..2315b06
--- /dev/null
+++ b/expand.c
@@ -0,0 +1,605 @@
+/* Variable expansion functions for GNU Make.
+Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
+1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
+2010 Free Software Foundation, Inc.
+This file is part of GNU Make.
+
+GNU Make 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 of the License, or (at your option) any later
+version.
+
+GNU Make 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, see <http://www.gnu.org/licenses/>.  */
+
+#include "make.h"
+
+#include <assert.h>
+
+#include "filedef.h"
+#include "job.h"
+#include "commands.h"
+#include "variable.h"
+#include "rule.h"
+
+/* Initially, any errors reported when expanding strings will be reported
+   against the file where the error appears.  */
+const struct floc **expanding_var = &reading_file;
+
+/* The next two describe the variable output buffer.
+   This buffer is used to hold the variable-expansion of a line of the
+   makefile.  It is made bigger with realloc whenever it is too small.
+   variable_buffer_length is the size currently allocated.
+   variable_buffer is the address of the buffer.
+
+   For efficiency, it's guaranteed that the buffer will always have
+   VARIABLE_BUFFER_ZONE extra bytes allocated.  This allows you to add a few
+   extra chars without having to call a function.  Note you should never use
+   these bytes unless you're _sure_ you have room (you know when the buffer
+   length was last checked.  */
+
+#define VARIABLE_BUFFER_ZONE    5
+
+static unsigned int variable_buffer_length;
+char *variable_buffer;
+
+/* Subroutine of variable_expand and friends:
+   The text to add is LENGTH chars starting at STRING to the variable_buffer.
+   The text is added to the buffer at PTR, and the updated pointer into
+   the buffer is returned as the value.  Thus, the value returned by
+   each call to variable_buffer_output should be the first argument to
+   the following call.  */
+
+char *
+variable_buffer_output (char *ptr, const char *string, unsigned int length)
+{
+  register unsigned int newlen = length + (ptr - variable_buffer);
+
+  if ((newlen + VARIABLE_BUFFER_ZONE) > variable_buffer_length)
+    {
+      unsigned int offset = ptr - variable_buffer;
+      variable_buffer_length = (newlen + 100 > 2 * variable_buffer_length
+				? newlen + 100
+				: 2 * variable_buffer_length);
+      variable_buffer = xrealloc (variable_buffer, variable_buffer_length);
+      ptr = variable_buffer + offset;
+    }
+
+  memcpy (ptr, string, length);
+  return ptr + length;
+}
+
+/* Return a pointer to the beginning of the variable buffer.  */
+
+static char *
+initialize_variable_output (void)
+{
+  /* If we don't have a variable output buffer yet, get one.  */
+
+  if (variable_buffer == 0)
+    {
+      variable_buffer_length = 200;
+      variable_buffer = xmalloc (variable_buffer_length);
+      variable_buffer[0] = '\0';
+    }
+
+  return variable_buffer;
+}
+
+/* Recursively expand V.  The returned string is malloc'd.  */
+
+static char *allocated_variable_append (const struct variable *v);
+
+char *
+recursively_expand_for_file (struct variable *v, struct file *file)
+{
+  char *value;
+  const struct floc *this_var;
+  const struct floc **saved_varp;
+  struct variable_set_list *save = 0;
+  int set_reading = 0;
+
+  /* Don't install a new location if this location is empty.
+     This can happen for command-line variables, builtin variables, etc.  */
+  saved_varp = expanding_var;
+  if (v->fileinfo.filenm)
+    {
+      this_var = &v->fileinfo;
+      expanding_var = &this_var;
+    }
+
+  /* If we have no other file-reading context, use the variable's context. */
+  if (!reading_file)
+    {
+      set_reading = 1;
+      reading_file = &v->fileinfo;
+    }
+
+  if (v->expanding)
+    {
+      if (!v->exp_count)
+        /* Expanding V causes infinite recursion.  Lose.  */
+        fatal (*expanding_var,
+               _("Recursive variable `%s' references itself (eventually)"),
+               v->name);
+      --v->exp_count;
+    }
+
+  if (file)
+    {
+      save = current_variable_set_list;
+      current_variable_set_list = file->variables;
+    }
+
+  v->expanding = 1;
+  if (v->append)
+    value = allocated_variable_append (v);
+  else
+    value = allocated_variable_expand (v->value);
+  v->expanding = 0;
+
+  if (set_reading)
+    reading_file = 0;
+
+  if (file)
+    current_variable_set_list = save;
+
+  expanding_var = saved_varp;
+
+  return value;
+}
+
+/* Expand a simple reference to variable NAME, which is LENGTH chars long.  */
+
+#ifdef __GNUC__
+__inline
+#endif
+static char *
+reference_variable (char *o, const char *name, unsigned int length)
+{
+  struct variable *v;
+  char *value;
+
+  v = lookup_variable (name, length);
+
+  if (v == 0)
+    warn_undefined (name, length);
+
+  /* If there's no variable by that name or it has no value, stop now.  */
+  if (v == 0 || (*v->value == '\0' && !v->append))
+    return o;
+
+  value = (v->recursive ? recursively_expand (v) : v->value);
+
+  o = variable_buffer_output (o, value, strlen (value));
+
+  if (v->recursive)
+    free (value);
+
+  return o;
+}
+
+/* Scan STRING for variable references and expansion-function calls.  Only
+   LENGTH bytes of STRING are actually scanned.  If LENGTH is -1, scan until
+   a null byte is found.
+
+   Write the results to LINE, which must point into `variable_buffer'.  If
+   LINE is NULL, start at the beginning of the buffer.
+   Return a pointer to LINE, or to the beginning of the buffer if LINE is
+   NULL.
+ */
+char *
+variable_expand_string (char *line, const char *string, long length)
+{
+  struct variable *v;
+  const char *p, *p1;
+  char *abuf = NULL;
+  char *o;
+  unsigned int line_offset;
+
+  if (!line)
+    line = initialize_variable_output();
+  o = line;
+  line_offset = line - variable_buffer;
+
+  if (length == 0)
+    {
+      variable_buffer_output (o, "", 1);
+      return (variable_buffer);
+    }
+
+  /* If we want a subset of the string, allocate a temporary buffer for it.
+     Most of the functions we use here don't work with length limits.  */
+  if (length > 0 && string[length] != '\0')
+    {
+      abuf = xmalloc(length+1);
+      memcpy(abuf, string, length);
+      abuf[length] = '\0';
+      string = abuf;
+    }
+  p = string;
+
+  while (1)
+    {
+      /* Copy all following uninteresting chars all at once to the
+         variable output buffer, and skip them.  Uninteresting chars end
+	 at the next $ or the end of the input.  */
+
+      p1 = strchr (p, '$');
+
+      o = variable_buffer_output (o, p, p1 != 0 ? (unsigned int)(p1 - p) : strlen (p) + 1);
+
+      if (p1 == 0)
+	break;
+      p = p1 + 1;
+
+      /* Dispatch on the char that follows the $.  */
+
+      switch (*p)
+	{
+	case '$':
+	  /* $$ seen means output one $ to the variable output buffer.  */
+	  o = variable_buffer_output (o, p, 1);
+	  break;
+
+	case '(':
+	case '{':
+	  /* $(...) or ${...} is the general case of substitution.  */
+	  {
+	    char openparen = *p;
+	    char closeparen = (openparen == '(') ? ')' : '}';
+            const char *begp;
+	    const char *beg = p + 1;
+	    char *op;
+            char *abeg = NULL;
+	    const char *end, *colon;
+
+	    op = o;
+	    begp = p;
+	    if (handle_function (&op, &begp))
+	      {
+		o = op;
+		p = begp;
+		break;
+	      }
+
+	    /* Is there a variable reference inside the parens or braces?
+	       If so, expand it before expanding the entire reference.  */
+
+	    end = strchr (beg, closeparen);
+	    if (end == 0)
+              /* Unterminated variable reference.  */
+              fatal (*expanding_var, _("unterminated variable reference"));
+	    p1 = lindex (beg, end, '$');
+	    if (p1 != 0)
+	      {
+		/* BEG now points past the opening paren or brace.
+		   Count parens or braces until it is matched.  */
+		int count = 0;
+		for (p = beg; *p != '\0'; ++p)
+		  {
+		    if (*p == openparen)
+		      ++count;
+		    else if (*p == closeparen && --count < 0)
+		      break;
+		  }
+		/* If COUNT is >= 0, there were unmatched opening parens
+		   or braces, so we go to the simple case of a variable name
+		   such as `$($(a)'.  */
+		if (count < 0)
+		  {
+		    abeg = expand_argument (beg, p); /* Expand the name.  */
+		    beg = abeg;
+		    end = strchr (beg, '\0');
+		  }
+	      }
+	    else
+	      /* Advance P to the end of this reference.  After we are
+                 finished expanding this one, P will be incremented to
+                 continue the scan.  */
+	      p = end;
+
+	    /* This is not a reference to a built-in function and
+	       any variable references inside are now expanded.
+	       Is the resultant text a substitution reference?  */
+
+	    colon = lindex (beg, end, ':');
+	    if (colon)
+	      {
+		/* This looks like a substitution reference: $(FOO:A=B).  */
+		const char *subst_beg, *subst_end, *replace_beg, *replace_end;
+
+		subst_beg = colon + 1;
+		subst_end = lindex (subst_beg, end, '=');
+		if (subst_end == 0)
+		  /* There is no = in sight.  Punt on the substitution
+		     reference and treat this as a variable name containing
+		     a colon, in the code below.  */
+		  colon = 0;
+		else
+		  {
+		    replace_beg = subst_end + 1;
+		    replace_end = end;
+
+		    /* Extract the variable name before the colon
+		       and look up that variable.  */
+		    v = lookup_variable (beg, colon - beg);
+		    if (v == 0)
+		      warn_undefined (beg, colon - beg);
+
+                    /* If the variable is not empty, perform the
+                       substitution.  */
+		    if (v != 0 && *v->value != '\0')
+		      {
+			char *pattern, *replace, *ppercent, *rpercent;
+			char *value = (v->recursive
+                                       ? recursively_expand (v)
+				       : v->value);
+
+                        /* Copy the pattern and the replacement.  Add in an
+                           extra % at the beginning to use in case there
+                           isn't one in the pattern.  */
+                        pattern = alloca (subst_end - subst_beg + 2);
+                        *(pattern++) = '%';
+                        memcpy (pattern, subst_beg, subst_end - subst_beg);
+                        pattern[subst_end - subst_beg] = '\0';
+
+                        replace = alloca (replace_end - replace_beg + 2);
+                        *(replace++) = '%';
+                        memcpy (replace, replace_beg,
+                               replace_end - replace_beg);
+                        replace[replace_end - replace_beg] = '\0';
+
+                        /* Look for %.  Set the percent pointers properly
+                           based on whether we find one or not.  */
+			ppercent = find_percent (pattern);
+			if (ppercent)
+                          {
+                            ++ppercent;
+                            rpercent = find_percent (replace);
+                            if (rpercent)
+                              ++rpercent;
+                          }
+			else
+                          {
+                            ppercent = pattern;
+                            rpercent = replace;
+                            --pattern;
+                            --replace;
+                          }
+
+                        o = patsubst_expand_pat (o, value, pattern, replace,
+                                                 ppercent, rpercent);
+
+			if (v->recursive)
+			  free (value);
+		      }
+		  }
+	      }
+
+	    if (colon == 0)
+	      /* This is an ordinary variable reference.
+		 Look up the value of the variable.  */
+		o = reference_variable (o, beg, end - beg);
+
+	  if (abeg)
+	    free (abeg);
+	  }
+	  break;
+
+	case '\0':
+	  break;
+
+	default:
+	  if (isblank ((unsigned char)p[-1]))
+	    break;
+
+	  /* A $ followed by a random char is a variable reference:
+	     $a is equivalent to $(a).  */
+          o = reference_variable (o, p, 1);
+
+	  break;
+	}
+
+      if (*p == '\0')
+	break;
+
+      ++p;
+    }
+
+  if (abuf)
+    free (abuf);
+
+  variable_buffer_output (o, "", 1);
+  return (variable_buffer + line_offset);
+}
+
+/* Scan LINE for variable references and expansion-function calls.
+   Build in `variable_buffer' the result of expanding the references and calls.
+   Return the address of the resulting string, which is null-terminated
+   and is valid only until the next time this function is called.  */
+
+char *
+variable_expand (const char *line)
+{
+  return variable_expand_string(NULL, line, (long)-1);
+}
+
+/* Expand an argument for an expansion function.
+   The text starting at STR and ending at END is variable-expanded
+   into a null-terminated string that is returned as the value.
+   This is done without clobbering `variable_buffer' or the current
+   variable-expansion that is in progress.  */
+
+char *
+expand_argument (const char *str, const char *end)
+{
+  char *tmp, *alloc = NULL;
+  char *r;
+
+  if (str == end)
+    return xstrdup("");
+
+  if (!end || *end == '\0')
+    return allocated_variable_expand (str);
+
+  if (end - str + 1 > 1000)
+    tmp = alloc = xmalloc (end - str + 1);
+  else
+    tmp = alloca (end - str + 1);
+
+  memcpy (tmp, str, end - str);
+  tmp[end - str] = '\0';
+
+  r = allocated_variable_expand (tmp);
+
+  if (alloc)
+    free (alloc);
+
+  return r;
+}
+
+/* Expand LINE for FILE.  Error messages refer to the file and line where
+   FILE's commands were found.  Expansion uses FILE's variable set list.  */
+
+char *
+variable_expand_for_file (const char *line, struct file *file)
+{
+  char *result;
+  struct variable_set_list *savev;
+  const struct floc *savef;
+
+  if (file == 0)
+    return variable_expand (line);
+
+  savev = current_variable_set_list;
+  current_variable_set_list = file->variables;
+
+  savef = reading_file;
+  if (file->cmds && file->cmds->fileinfo.filenm)
+    reading_file = &file->cmds->fileinfo;
+  else
+    reading_file = 0;
+
+  result = variable_expand (line);
+
+  current_variable_set_list = savev;
+  reading_file = savef;
+
+  return result;
+}
+
+/* Like allocated_variable_expand, but for += target-specific variables.
+   First recursively construct the variable value from its appended parts in
+   any upper variable sets.  Then expand the resulting value.  */
+
+static char *
+variable_append (const char *name, unsigned int length,
+                 const struct variable_set_list *set)
+{
+  const struct variable *v;
+  char *buf = 0;
+
+  /* If there's nothing left to check, return the empty buffer.  */
+  if (!set)
+    return initialize_variable_output ();
+
+  /* Try to find the variable in this variable set.  */
+  v = lookup_variable_in_set (name, length, set->set);
+
+  /* If there isn't one, look to see if there's one in a set above us.  */
+  if (!v)
+    return variable_append (name, length, set->next);
+
+  /* If this variable type is append, first get any upper values.
+     If not, initialize the buffer.  */
+  if (v->append)
+    buf = variable_append (name, length, set->next);
+  else
+    buf = initialize_variable_output ();
+
+  /* Append this value to the buffer, and return it.
+     If we already have a value, first add a space.  */
+  if (buf > variable_buffer)
+    buf = variable_buffer_output (buf, " ", 1);
+
+  /* Either expand it or copy it, depending.  */
+  if (! v->recursive)
+    return variable_buffer_output (buf, v->value, strlen (v->value));
+
+  buf = variable_expand_string (buf, v->value, strlen (v->value));
+  return (buf + strlen (buf));
+}
+
+
+static char *
+allocated_variable_append (const struct variable *v)
+{
+  char *val;
+
+  /* Construct the appended variable value.  */
+
+  char *obuf = variable_buffer;
+  unsigned int olen = variable_buffer_length;
+
+  variable_buffer = 0;
+
+  val = variable_append (v->name, strlen (v->name), current_variable_set_list);
+  variable_buffer_output (val, "", 1);
+  val = variable_buffer;
+
+  variable_buffer = obuf;
+  variable_buffer_length = olen;
+
+  return val;
+}
+
+/* Like variable_expand_for_file, but the returned string is malloc'd.
+   This function is called a lot.  It wants to be efficient.  */
+
+char *
+allocated_variable_expand_for_file (const char *line, struct file *file)
+{
+  char *value;
+
+  char *obuf = variable_buffer;
+  unsigned int olen = variable_buffer_length;
+
+  variable_buffer = 0;
+
+  value = variable_expand_for_file (line, file);
+
+  variable_buffer = obuf;
+  variable_buffer_length = olen;
+
+  return value;
+}
+
+/* Install a new variable_buffer context, returning the current one for
+   safe-keeping.  */
+
+void
+install_variable_buffer (char **bufp, unsigned int *lenp)
+{
+  *bufp = variable_buffer;
+  *lenp = variable_buffer_length;
+
+  variable_buffer = 0;
+  initialize_variable_output ();
+}
+
+/* Restore a previously-saved variable_buffer setting (free the current one).
+ */
+
+void
+restore_variable_buffer (char *buf, unsigned int len)
+{
+  free (variable_buffer);
+
+  variable_buffer = buf;
+  variable_buffer_length = len;
+}