(variable_expand): Rewrote computed variable name and substitution

reference handling to be simpler.  First expand the entire text between the
parens if it contains any $s, then examine the result of that for
subtitution references and do no further expansion while parsing them.

diff --git a/expand.c b/expand.c
index bbbd6a7..867cf91 100644 (file)
--- a/expand.c
+++ b/expand.c
@@ -1,5 +1,5 @@
 /* Variable expansion functions for GNU Make.
-Copyright (C) 1988, 1989, 1991, 1992, 1993 Free Software Foundation, Inc.
+Copyright (C) 1988, 89, 91, 92, 93, 95 Free Software Foundation, Inc.
 This file is part of GNU Make.
 
 GNU Make is free software; you can redistribute it and/or modify
@@ -197,9 +197,9 @@ variable_expand (line)
            char openparen = *p;
            char closeparen = (openparen == '(') ? ')' : '}';
            register char *beg = p + 1;
+           int free_beg = 0;
            char *op, *begp;
-           char *end;
-           char *colon = 0;
+           char *end, *colon;
 
            op = o;
            begp = p;
@@ -213,10 +213,18 @@ variable_expand (line)
            /* Is there a variable reference inside the parens or braces?
               If so, expand it before expanding the entire reference.  */
 
-           p1 = index (beg, closeparen);
+           end = index (beg, closeparen);
+           if (end == 0)
+             {
+               /* Unterminated variable reference.  */
+               if (reading_filename != 0)
+                 makefile_fatal (reading_filename, *reading_lineno_ptr,
+                                 "unterminated variable reference");
+               else
+                 fatal ("unterminated variable reference");
+             }
+           p1 = lindex (beg, end, '$');
            if (p1 != 0)
-             p1 = lindex (beg, p1, '$');
-           if (p1 != 0 && lindex (beg, p1, ':') == 0)
              {
                /* BEG now points past the opening paren or brace.
                   Count parens or braces until it is matched.  */
@@ -227,133 +235,107 @@ variable_expand (line)
                      ++count;
                    else if (*p == closeparen && --count < 0)
                      break;
-                   else if (colon == 0 && count == 0 && *p == ':')
-                     /* Record where we found a colon, which
-                        indicates a substitution reference.
-                        We want to expand the text before the
-                        reference only.  */
-                     colon = p;
                  }
                /* 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)
                  {
-                   char *name = expand_argument (beg, colon == 0 ? p : colon);
-                   unsigned int namelen = strlen (name);
-                   if (colon == 0)
-                     {
-                       /* This is a simple reference to the expanded name.  */
-                       o = reference_variable (o, name, namelen);
-                       free (name);
-                       break;
-                     }
-                   else
-                     {
-                       /* This is a substitution reference to the expanded
-                          name.  We replace the pending text with a copy
-                          containing the expanded name in place of the
-                          original name, and then fall through to
-                          the normal substitution reference code below.  */
-                       unsigned int restlen = strlen (colon) + 1;
-                       beg = (char *) alloca (namelen + restlen);
-                       bcopy (name, beg, namelen);
-                       bcopy (colon, &beg[namelen], restlen);
-                       /* Point COLON into the new copy.  */
-                       colon = &beg[namelen];
-                     }
+                   beg = expand_argument (beg, p); /* Expand the name.  */
+                   free_beg = 1; /* Remember to free BEG when finished.  */
+                   end = index (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
-              it does not contain any variable references inside.
-              There are several things it could be.  */
+              any variable references inside are now expanded.
+              Is the resultant text a substitution reference?  */
 
-           if (colon == 0)
-             colon = index (beg, ':');
-           if (colon != 0 && lindex (beg, colon, closeparen) == 0)
+           colon = index (beg, ':');
+           if (colon != 0)
              {
-               /* This is a substitution reference: $(FOO:A=B).  */
-               int count;
+               /* This looks like a substitution reference: $(FOO:A=B).  */
                char *subst_beg, *subst_end, *replace_beg, *replace_end;
 
-               v = lookup_variable (beg, colon - beg);
-               if (v == 0)
-                 warn_undefined (beg, colon - beg);
-
                subst_beg = colon + 1;
-               count = 0;
-               for (p = subst_beg; *p != '\0'; ++p)
+               subst_end = index (subst_beg, '=');
+               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
                  {
-                   if (*p == openparen)
-                     ++count;
-                   else if (*p == closeparen)
-                     --count;
-                   else if (*p == '=' && count <= 0)
-                     break;
-                 }
-               if (count > 0)
-                 /* There were unmatched opening parens.  */
-                 return initialize_variable_output ();
-               subst_end = p;
-
-               replace_beg = p + 1;
-               count = 0;
-               for (p = replace_beg; *p != '\0'; ++p)
-                 {
-                   if (*p == openparen)
-                     ++count;
-                   else if (*p == closeparen && --count < 0)
-                     break;
-                 }
-               if (count > 0)
-                 /* There were unmatched opening parens.  */
-                 return initialize_variable_output ();
-               end = p;
-               replace_end = p;
+                   replace_beg = subst_end + 1;
+                   replace_end = end;
 
-               p = expand_argument (subst_beg, subst_end);
-               p1 = expand_argument (replace_beg, replace_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 (v != 0 && *v->value != '\0')
-                 {
-                   char *value = (v->recursive ? recursively_expand (v)
-                                  : v->value);
-                   char *percent = find_percent (p);
-                   if (percent != 0)
-                     o = patsubst_expand (o, value, p, p1,
-                                          percent, (char *) 0);
-                   else
-                     o = subst_expand (o, value,
-                                       p, p1, strlen (p), strlen (p1),
-                                       0, 1);
-                   if (v->recursive)
-                     free (value);
+                   if (v != 0 && *v->value != '\0')
+                     {
+                       char *value = (v->recursive ? recursively_expand (v)
+                                      : v->value);
+                       char *pattern, *percent;
+                       if (free_beg)
+                         {
+                           *subst_end = '\0';
+                           pattern = subst_beg;
+                         }
+                       else
+                         {
+                           pattern = alloca (subst_end - subst_beg + 1);
+                           bcopy (subst_beg, pattern, subst_end - subst_beg);
+                           pattern[subst_end - subst_beg] = '\0';
+                         }
+                       percent = find_percent (pattern);
+                       if (percent != 0)
+                         {
+                           char *replace;
+                           if (free_beg)
+                             {
+                               *replace_end = '\0';
+                               replace = replace_beg;
+                             }
+                           else
+                             {
+                               replace = alloca (replace_end - replace_beg
+                                                 + 1);
+                               bcopy (replace_beg, replace,
+                                      replace_end - replace_beg);
+                               replace[replace_end - replace_beg] = '\0';
+                             }
+                           
+                           o = patsubst_expand (o, value, pattern, replace,
+                                                percent, (char *) 0);
+                         }
+                       else
+                         o = subst_expand (o, value,
+                                           pattern, replace_beg,
+                                           strlen (pattern),
+                                           end - replace_beg,
+                                           0, 1);
+                       if (v->recursive)
+                         free (value);
+                     }
                  }
-
-               free (p);
-               free (p1);
              }
 
-           /* No, this must be an ordinary variable reference.  */
-           else
-             {
-               /* Look up the value of the variable.  */
-               end = index (beg, closeparen);
-               if (end == 0)
-                 {
-                   /* Unterminated variable reference.  */
-                   if (reading_filename != 0)
-                     makefile_fatal (reading_filename, *reading_lineno_ptr,
-                                     "unterminated variable reference");
-                   else
-                     fatal ("unterminated variable reference");
-                 }
+           if (colon == 0)
+             /* This is an ordinary variable reference.
+                Look up the value of the variable.  */
                o = reference_variable (o, beg, end - beg);
-             }
 
-           /* Advance p past the variable reference to resume scan.  */
-           p = end;
+         if (free_beg)
+           free (beg);
          }
          break;