Formerly expand.c.~8~

diff --git a/expand.c b/expand.c
index fc6c200..5582a97 100644 (file)
--- a/expand.c
+++ b/expand.c
@@ -103,6 +103,30 @@ recursively_expand (v)
 
   return value;
 }
+
+/* Expand a simple reference to variable NAME, which LENGTH chars long.  */
+
+#ifdef __GNUC__
+__inline
+#endif
+static char *
+reference_variable (o, name, length)
+     char *o;
+     char *name;
+     unsigned int length;
+{
+  register struct variable *v = lookup_variable (name, length);
+
+  if (v != 0 && *v->value != '\0')
+    {
+      char *value = (v->recursive ? recursively_expand (v) : v->value);
+      o = variable_buffer_output (o, value, strlen (value));
+      if (v->recursive)
+       free (value);
+    }
+
+  return o;
+}
 \f
 /* Scan LINE for variable references and expansion-function calls.
    Build in `variable_buffer' the result of expanding the references and calls.
@@ -151,6 +175,7 @@ variable_expand (line)
            register char *beg = p + 1;
            char *op, *begp;
            char *end;
+           char *colon = 0;
 
            op = o;
            begp = p;
@@ -167,7 +192,7 @@ variable_expand (line)
            p1 = index (beg, closeparen);
            if (p1 != 0)
              p1 = lindex (beg, p1, '$');
-           if (p1 != 0)
+           if (p1 != 0 && lindex (beg, p1, ':') == 0)
              {
                /* BEG now points past the opening paren or brace.
                   Count parens or braces until it is matched.  */
@@ -178,22 +203,41 @@ variable_expand (line)
                      ++count;
                    else if (*p == closeparen && --count < 0)
                      break;
+                   else if (colon == 0 && count == 0 && *p == ':')
+                     /* Record where we found a colon, which
+                        indicates a substitution reference.
+                        We want to expand the text before the
+                        reference only.  */
+                     colon = p;
                  }
                /* If COUNT is >= 0, there were unmatched opening parens
                   or braces, so we go to the simple case of a variable name
                   such as `$($(a)'.  */
                if (count < 0)
                  {
-                   char *name = expand_argument (beg, p);
-                   static char start[3] = { '$', }, end[2];
-                   start[1] = openparen;
-                   end[0] = closeparen;
-                   p1 = concat (start, name, end);
-                   free (name);
-                   name = allocated_variable_expand (p1);
-                   o = variable_buffer_output (o, name, strlen (name));
-                   free (name);
-                   break;
+                   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];
+                     }
                  }
              }
 
@@ -201,17 +245,17 @@ variable_expand (line)
               it does not contain any variable references inside.
               There are several things it could be.  */
 
-           p = index (beg, ':');
-           if (p != 0 && lindex (beg, p, closeparen) == 0)
+           if (colon == 0)
+             colon = index (beg, ':');
+           if (colon != 0 && lindex (beg, colon, closeparen) == 0)
              {
                /* This is a substitution reference: $(FOO:A=B).  */
                int count;
-               char *subst_beg, *replace_beg;
-               unsigned int subst_len, replace_len;
+               char *subst_beg, *subst_end, *replace_beg, *replace_end;
 
-               v = lookup_variable (beg, p - beg);
+               v = lookup_variable (beg, colon - beg);
 
-               subst_beg = p + 1;
+               subst_beg = colon + 1;
                count = 0;
                for (p = subst_beg; *p != '\0'; ++p)
                  {
@@ -225,7 +269,7 @@ variable_expand (line)
                if (count > 0)
                  /* There were unmatched opening parens.  */
                  return initialize_variable_output ();
-               subst_len = p - subst_beg;
+               subst_end = p;
 
                replace_beg = p + 1;
                count = 0;
@@ -240,27 +284,29 @@ variable_expand (line)
                  /* There were unmatched opening parens.  */
                  return initialize_variable_output ();
                end = p;
-               replace_len = p - replace_beg;
+               replace_end = p;
+
+               p = expand_argument (subst_beg, subst_end);
+               p1 = expand_argument (replace_beg, replace_end);
 
                if (v != 0 && *v->value != '\0')
                  {
                    char *value = (v->recursive ? recursively_expand (v)
                                   : v->value);
-                   if (lindex (subst_beg, subst_beg + subst_len, '%') != 0)
-                     {
-                       p = savestring (subst_beg, subst_len);
-                       p1 = savestring (replace_beg, replace_len);
-                       o = patsubst_expand (o, value, p, p1,
-                                            (char *) 0, (char *) 0);
-                       free (p);
-                       free (p1);
-                     }
+                   char *percent = find_percent (p);
+                   if (percent != 0)
+                     o = patsubst_expand (o, value, p, p1,
+                                          percent, (char *) 0);
                    else
-                     o = subst_expand (o, value, subst_beg, replace_beg,
-                                       subst_len, replace_len, 0, 1);
+                     o = subst_expand (o, value,
+                                       p, p1, strlen (p), strlen (p1),
+                                       0, 1);
                    if (v->recursive)
                      free (value);
                  }
+
+               free (p);
+               free (p1);
              }
 
            /* No, this must be an ordinary variable reference.  */
@@ -270,16 +316,7 @@ variable_expand (line)
                end = index (beg, closeparen);
                if (end == 0)
                  return initialize_variable_output ();
-               v = lookup_variable (beg, end - beg);
-
-               if (v != 0 && *v->value != '\0')
-                 {
-                   char *value = (v->recursive ? recursively_expand (v)
-                                  : v->value);
-                   o = variable_buffer_output (o, value, strlen (value));
-                   if (v->recursive)
-                     free (value);
-                 }
+               o = reference_variable (o, beg, end - beg);
              }
 
            /* Advance p past the variable reference to resume scan.  */
@@ -333,12 +370,18 @@ char *
 expand_argument (str, end)
      char *str, *end;
 {
-  char *tmp = savestring (str, end - str);
-  char *value = allocated_variable_expand (tmp);
+  char *tmp;
 
-  free (tmp);
+  if (*end == '\0')
+    tmp = str;
+  else
+    {
+      tmp = (char *) alloca (end - str + 1);
+      bcopy (str, tmp, end - str);
+      tmp[end - str] = '\0';
+    }
 
-  return value;
+  return allocated_variable_expand (tmp);
 }
 \f
 /* Expand LINE for FILE.  Error messages refer to the file and line where