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Formerly variable.c.~21~

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This commit is contained in:
Roland McGrath 1993-04-12 20:02:24 +00:00
parent 5136f317d2
commit 2cc84f7c97
1 changed files with 71 additions and 13 deletions
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84
variable.c
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@ -558,8 +558,8 @@ try_variable_definition (filename, lineno, line, origin)
register char *p = line;
register char *beg;
register char *end;
register int recursive;
char *name, *expanded_name;
enum { bogus, simple, recursive, append } flavor = bogus;
char *name, *expanded_name, *value;
struct variable *v;
while (1)
@ -569,32 +569,38 @@ try_variable_definition (filename, lineno, line, origin)
return 0;
if (c == '=')
{
recursive = 1;
end = p - 1;
flavor = recursive;
break;
}
else if (c == ':')
if (*p == '=')
{
++p;
recursive = 0;
end = p++ - 1;
flavor = simple;
break;
}
else
/* A colon other than := is a rule line, not a variable defn. */
return 0;
else if (c == '+' && *p == '=')
{
end = p++ - 1;
flavor = append;
break;
}
}
beg = next_token (line);
end = p - 1;
if (!recursive)
--end;
while (isblank (end[-1]))
--end;
beg = next_token (line);
p = next_token (p);
/* Expand the name, so "$(foo)bar = baz" works. */
name = savestring (beg, end - beg);
name = (char *) alloca (end - beg + 1);
bcopy (beg, name, end - beg);
name[end - beg] = '\0';
expanded_name = allocated_variable_expand (name);
free (name);
if (expanded_name[0] == '\0')
{
@ -604,9 +610,61 @@ try_variable_definition (filename, lineno, line, origin)
makefile_fatal (filename, lineno, "empty variable name");
}
/* Calculate the variable's new value in VALUE. */
switch (flavor)
{
case bogus:
/* Should not be possible. */
abort ();
break;
case simple:
/* A simple variable definition "var := value". Expand the value. */
value = variable_expand (p);
break;
case recursive:
/* A recursive variable definition "var = value".
The value is used verbatim. */
value = p;
break;
case append:
/* An appending variable definition "var += value".
Extract the old value and append the new one. */
v = lookup_variable (expanded_name, strlen (expanded_name));
if (v == 0)
{
/* There was no old value.
This becomes a normal recursive definition. */
value = p;
flavor = recursive;
}
else
{
/* Paste the old and new values together in VALUE. */
unsigned int oldlen, newlen;
if (v->recursive)
/* The previous definition of the variable was recursive.
The new value comes from the unexpanded old and new values. */
flavor = recursive;
else
/* The previous definition of the variable was simple.
The new value comes from the old value, which was expanded
when it was set; and from the expanded new value. */
p = variable_expand (p);
oldlen = strlen (v->value);
newlen = strlen (p);
value = (char *) alloca (oldlen + 1 + newlen + 1);
bcopy (v->value, value, oldlen);
value[oldlen] = ' ';
bcopy (p, &value[oldlen + 1], newlen + 1);
}
}
v = define_variable (expanded_name, strlen (expanded_name),
recursive ? p : variable_expand (p),
origin, recursive);
value, origin, flavor == recursive);
free (expanded_name);