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/* Internals of variables for GNU Make.
Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993 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 2, 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 GNU Make; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "make.h"
#include "commands.h"
#include "variable.h"
#include "dep.h"
#include "file.h"
/* Hash table of all global variable definitions. */
#ifndef VARIABLE_BUCKETS
#define VARIABLE_BUCKETS 523
#endif
#ifndef PERFILE_VARIABLE_BUCKETS
#define PERFILE_VARIABLE_BUCKETS 23
#endif
#ifndef SMALL_SCOPE_VARIABLE_BUCKETS
#define SMALL_SCOPE_VARIABLE_BUCKETS 13
#endif
static struct variable *variable_table[VARIABLE_BUCKETS];
static struct variable_set global_variable_set
= { variable_table, VARIABLE_BUCKETS };
static struct variable_set_list global_setlist
= { 0, &global_variable_set };
struct variable_set_list *current_variable_set_list = &global_setlist;
/* Implement variables. */
/* Define variable named NAME with value VALUE in SET. VALUE is copied.
LENGTH is the length of NAME, which does not need to be null-terminated.
ORIGIN specifies the origin of the variable (makefile, command line
or environment).
If RECURSIVE is nonzero a flag is set in the variable saying
that it should be recursively re-expanded. */
static struct variable *
define_variable_in_set (name, length, value, origin, recursive, set)
char *name;
unsigned int length;
char *value;
enum variable_origin origin;
int recursive;
struct variable_set *set;
{
register unsigned int i;
register unsigned int hashval;
register struct variable *v;
hashval = 0;
for (i = 0; i < length; ++i)
HASH (hashval, name[i]);
hashval %= set->buckets;
for (v = set->table[hashval]; v != 0; v = v->next)
if (*v->name == *name
&& !strncmp (v->name + 1, name + 1, length - 1)
&& v->name[length] == '\0')
break;
if (env_overrides && origin == o_env)
origin = o_env_override;
if (v != 0)
{
if (env_overrides && v->origin == o_env)
/* V came from in the environment. Since it was defined
before the switches were parsed, it wasn't affected by -e. */
v->origin = o_env_override;
/* A variable of this name is already defined.
If the old definition is from a stronger source
than this one, don't redefine it. */
if ((int) origin >= (int) v->origin)
{
if (v->value != 0)
free (v->value);
v->value = savestring (value, strlen (value));
v->origin = origin;
v->recursive = recursive;
}
return v;
}
/* Create a new variable definition and add it to the hash table. */
v = (struct variable *) xmalloc (sizeof (struct variable));
v->name = savestring (name, length);
v->value = savestring (value, strlen (value));
v->origin = origin;
v->recursive = recursive;
v->expanding = 0;
v->export = v_default;
v->next = set->table[hashval];
set->table[hashval] = v;
return v;
}
/* Define a variable in the current variable set. */
struct variable *
define_variable (name, length, value, origin, recursive)
char *name;
unsigned int length;
char *value;
enum variable_origin origin;
int recursive;
{
return define_variable_in_set (name, length, value, origin, recursive,
current_variable_set_list->set);
}
/* Define a variable in FILE's variable set. */
struct variable *
define_variable_for_file (name, length, value, origin, recursive, file)
char *name;
unsigned int length;
char *value;
enum variable_origin origin;
int recursive;
struct file *file;
{
return define_variable_in_set (name, length, value, origin, recursive,
file->variables->set);
}
/* Lookup a variable whose name is a string starting at NAME
and with LENGTH chars. NAME need not be null-terminated.
Returns address of the `struct variable' containing all info
on the variable, or nil if no such variable is defined. */
struct variable *
lookup_variable (name, length)
char *name;
unsigned int length;
{
register struct variable_set_list *setlist;
register unsigned int i;
register unsigned int rawhash = 0;
for (i = 0; i < length; ++i)
HASH (rawhash, name[i]);
for (setlist = current_variable_set_list;
setlist != 0; setlist = setlist->next)
{
register struct variable_set *set = setlist->set;
register unsigned int hashval = rawhash % set->buckets;
register struct variable *v;
for (v = set->table[hashval]; v != 0; v = v->next)
if (*v->name == *name
&& !strncmp (v->name + 1, name + 1, length - 1)
&& v->name[length] == 0)
return v;
}
return 0;
}
/* Initialize FILE's variable set list. If FILE already has a variable set
list, the topmost variable set is left intact, but the the rest of the
chain is replaced with FILE->parent's setlist. */
void
initialize_file_variables (file)
struct file *file;
{
register struct variable_set_list *l = file->variables;
if (l == 0)
{
l = (struct variable_set_list *)
xmalloc (sizeof (struct variable_set_list));
l->set = (struct variable_set *) xmalloc (sizeof (struct variable_set));
l->set->buckets = PERFILE_VARIABLE_BUCKETS;
l->set->table = (struct variable **)
xmalloc (l->set->buckets * sizeof (struct variable *));
bzero ((char *) l->set->table,
l->set->buckets * sizeof (struct variable *));
file->variables = l;
}
if (file->parent == 0)
l->next = &global_setlist;
else
{
if (file->parent->variables == 0)
initialize_file_variables (file->parent);
l->next = file->parent->variables;
}
}
/* Pop the top set off the current variable set list,
and free all its storage. */
void
pop_variable_scope ()
{
register struct variable_set_list *setlist = current_variable_set_list;
register struct variable_set *set = setlist->set;
register unsigned int i;
current_variable_set_list = setlist->next;
free ((char *) setlist);
for (i = 0; i < set->buckets; ++i)
{
register struct variable *next = set->table[i];
while (next != 0)
{
register struct variable *v = next;
next = v->next;
free (v->name);
free ((char *) v);
}
}
free ((char *) set->table);
free ((char *) set);
}
/* Create a new variable set and push it on the current setlist. */
void
push_new_variable_scope ()
{
register struct variable_set_list *setlist;
register struct variable_set *set;
set = (struct variable_set *) xmalloc (sizeof (struct variable_set));
set->buckets = SMALL_SCOPE_VARIABLE_BUCKETS;
set->table = (struct variable **)
xmalloc (set->buckets * sizeof (struct variable *));
bzero ((char *) set->table, set->buckets * sizeof (struct variable *));
setlist = (struct variable_set_list *)
xmalloc (sizeof (struct variable_set_list));
setlist->set = set;
setlist->next = current_variable_set_list;
current_variable_set_list = setlist;
}
/* Merge SET1 into SET0, freeing unused storage in SET1. */
static void
merge_variable_sets (set0, set1)
struct variable_set *set0, *set1;
{
register unsigned int bucket1;
for (bucket1 = 0; bucket1 < set1->buckets; ++bucket1)
{
register struct variable *v1 = set1->table[bucket1];
while (v1 != 0)
{
struct variable *next = v1->next;
unsigned int bucket0;
register struct variable *v0;
if (set1->buckets >= set0->buckets)
bucket0 = bucket1;
else
{
register char *n;
bucket0 = 0;
for (n = v1->name; *n != '\0'; ++n)
HASH (bucket0, *n);
}
bucket0 %= set0->buckets;
for (v0 = set0->table[bucket0]; v0 != 0; v0 = v0->next)
if (streq (v0->name, v1->name))
break;
if (v0 == 0)
{
/* There is no variable in SET0 with the same name. */
v1->next = set0->table[bucket0];
set0->table[bucket0] = v1;
}
else
{
/* The same variable exists in both sets.
SET0 takes precedence. */
free (v1->value);
free ((char *) v1);
}
v1 = next;
}
}
}
/* Merge SETLIST1 into SETLIST0, freeing unused storage in SETLIST1. */
void
merge_variable_set_lists (setlist0, setlist1)
struct variable_set_list **setlist0, *setlist1;
{
register struct variable_set_list *list0 = *setlist0;
struct variable_set_list *last0 = 0;
while (setlist1 != 0 && list0 != 0)
{
struct variable_set_list *next = setlist1;
setlist1 = setlist1->next;
merge_variable_sets (list0->set, next->set);
free ((char *) next);
last0 = list0;
list0 = list0->next;
}
if (setlist1 != 0)
{
if (last0 == 0)
*setlist0 = setlist1;
else
last0->next = setlist1;
}
}
/* Define the automatic variables, and record the addresses
of their structures so we can change their values quickly. */
void
define_automatic_variables ()
{
extern char default_shell[];
register struct variable *v;
char buf[100];
sprintf (buf, "%u", makelevel);
(void) define_variable ("MAKELEVEL", 9, buf, o_env, 0);
/* This won't override any definition, but it
will provide one if there isn't one there. */
v = define_variable ("SHELL", 5, default_shell, o_default, 0);
v->export = v_export;
/* Don't let SHELL come from the environment. */
if (*v->value == '\0' || v->origin == o_env || v->origin == o_env_override)
{
free (v->value);
v->origin = o_file;
v->value = savestring (default_shell, 7);
}
/* Make sure MAKEFILES gets exported if it is set. */
v = define_variable ("MAKEFILES", 9, "", o_default, 0);
v->export = v_ifset;
}
int export_all_variables;
/* Create a new environment for FILE's commands.
The child's MAKELEVEL variable is incremented. */
char **
target_environment (file)
struct file *file;
{
register struct variable_set_list *s;
struct variable_bucket
{
struct variable_bucket *next;
struct variable *variable;
};
struct variable_bucket **table;
unsigned int buckets;
register unsigned int i;
register unsigned nvariables;
char **result;
unsigned int mklev_hash;
/* Find the lowest number of buckets in any set in the list. */
s = file->variables;
buckets = s->set->buckets;
for (s = s->next; s != 0; s = s->next)
if (s->set->buckets < buckets)
buckets = s->set->buckets;
/* Find the hash value of `MAKELEVEL' will fall into. */
{
char *p = "MAKELEVEL";
mklev_hash = 0;
while (*p != '\0')
HASH (mklev_hash, *p++);
}
/* Temporarily allocate a table with that many buckets. */
table = (struct variable_bucket **)
alloca (buckets * sizeof (struct variable_bucket *));
bzero ((char *) table, buckets * sizeof (struct variable_bucket *));
/* Run through all the variable sets in the list,
accumulating variables in TABLE. */
nvariables = 0;
for (s = file->variables; s != 0; s = s->next)
{
register struct variable_set *set = s->set;
for (i = 0; i < set->buckets; ++i)
{
register struct variable *v;
for (v = set->table[i]; v != 0; v = v->next)
{
extern char *getenv ();
unsigned int j = i % buckets;
register struct variable_bucket *ov;
register char *p = v->name;
if (i == mklev_hash % set->buckets
&& streq (v->name, "MAKELEVEL"))
/* Don't include MAKELEVEL because it will be
added specially at the end. */
continue;
switch (v->export)
{
case v_default:
if (!export_all_variables
&& v->origin != o_command
&& v->origin != o_env && v->origin != o_env_override
&& !(v->origin == o_file && getenv (p) != 0))
continue;
if (*p != '_' && (*p < 'A' || *p > 'Z')
&& (*p < 'a' || *p > 'z'))
continue;
for (++p; *p != '\0'; ++p)
if (*p != '_' && (*p < 'a' || *p > 'z')
&& (*p < 'A' || *p > 'Z') && (*p < '0' || *p > '9'))
break;
if (*p != '\0')
continue;
case v_export:
break;
case v_noexport:
continue;
case v_ifset:
if (v->origin == o_default)
continue;
break;
}
for (ov = table[j]; ov != 0; ov = ov->next)
if (streq (v->name, ov->variable->name))
break;
if (ov == 0)
{
register struct variable_bucket *entry;
entry = (struct variable_bucket *)
alloca (sizeof (struct variable_bucket));
entry->next = table[j];
entry->variable = v;
table[j] = entry;
++nvariables;
}
}
}
}
result = (char **) xmalloc ((nvariables + 2) * sizeof (char *));
nvariables = 0;
for (i = 0; i < buckets; ++i)
{
register struct variable_bucket *b;
for (b = table[i]; b != 0; b = b->next)
{
register struct variable *v = b->variable;
/* If V is recursively expanded, expand its value. */
char *value = v->recursive ? recursively_expand (v) : v->value;
result[nvariables++] = concat (v->name, "=", value);
if (v->recursive)
free (value);
}
}
result[nvariables] = (char *) xmalloc (100);
(void) sprintf (result[nvariables], "MAKELEVEL=%u", makelevel + 1);
result[++nvariables] = 0;
return result;
}
/* Try to interpret LINE (a null-terminated string) as a variable definition.
ORIGIN may be o_file, o_override, o_env, o_env_override,
or o_command specifying that the variable definition comes
from a makefile, an override directive, the environment with
or without the -e switch, or the command line.
A variable definition has the form "name = value" or "name := value".
Any whitespace around the "=" or ":=" is removed. The first form
defines a variable that is recursively re-evaluated. The second form
defines a variable whose value is variable-expanded at the time of
definition and then is evaluated only once at the time of expansion.
If a variable was defined, a pointer to its `struct variable' is returned.
If not, NULL is returned. */
struct variable *
try_variable_definition (line, origin)
char *line;
enum variable_origin origin;
{
register int c;
register char *p = line;
register char *beg;
register char *end;
register int recursive;
char *name, *expanded_name;
struct variable *v;
while (1)
{
c = *p++;
if (c == '\0' || c == '#')
return 0;
if (c == '=')
{
recursive = 1;
break;
}
else if (c == ':')
if (*p == '=')
{
++p;
recursive = 0;
break;
}
else
return 0;
}
beg = next_token (line);
end = p - 1;
if (!recursive)
--end;
while (isblank (end[-1]))
--end;
p = next_token (p);
/* Expand the name, so "$(foo)bar = baz" works. */
name = savestring (beg, end - beg);
expanded_name = allocated_variable_expand (name);
free (name);
v = define_variable (expanded_name, strlen (expanded_name),
recursive ? p : variable_expand (p),
origin, recursive);
free (expanded_name);
return v;
}
/* Print information for variable V, prefixing it with PREFIX. */
static void
print_variable (v, prefix)
register struct variable *v;
char *prefix;
{
char *origin;
switch (v->origin)
{
case o_default:
origin = "default";
break;
case o_env:
origin = "environment";
break;
case o_file:
origin = "makefile";
break;
case o_env_override:
origin = "environment under -e";
break;
case o_command:
origin = "command line";
break;
case o_override:
origin = "`override' directive";
break;
case o_automatic:
origin = "automatic";
break;
case o_invalid:
default:
abort ();
break;
}
printf ("# %s\n", origin);
fputs (prefix, stdout);
/* Is this a `define'? */
if (v->recursive && index (v->value, '\n') != 0)
printf ("define %s\n%s\nendef\n", v->name, v->value);
else
{
register char *p;
printf ("%s %s= ", v->name, v->recursive ? "" : ":");
/* Check if the value is just whitespace. */
p = next_token (v->value);
if (p != v->value && *p == '\0')
/* All whitespace. */
printf ("$(subst ,,%s)", v->value);
else if (v->recursive)
fputs (v->value, stdout);
else
/* Double up dollar signs. */
for (p = v->value; *p != '\0'; ++p)
{
if (*p == '$')
putchar ('$');
putchar (*p);
}
putchar ('\n');
}
}
/* Print all the variables in SET. PREFIX is printed before
the actual variable definitions (everything else is comments). */
static void
print_variable_set (set, prefix)
register struct variable_set *set;
char *prefix;
{
register unsigned int i, nvariables, per_bucket;
register struct variable *v;
per_bucket = nvariables = 0;
for (i = 0; i < set->buckets; ++i)
{
register unsigned int this_bucket = 0;
for (v = set->table[i]; v != 0; v = v->next)
{
++this_bucket;
print_variable (v, prefix);
}
nvariables += this_bucket;
if (this_bucket > per_bucket)
per_bucket = this_bucket;
}
if (nvariables == 0)
puts ("# No variables.");
else
{
printf ("# %u variables in %u hash buckets.\n",
nvariables, set->buckets);
#ifndef NO_FLOAT
printf ("# average of %.1f variables per bucket, \
max %u in one bucket.\n",
((double) nvariables) * 100.0 / (double) set->buckets,
per_bucket);
#endif
}
}
/* Print the data base of variables. */
void
print_variable_data_base ()
{
puts ("\n# Variables\n");
print_variable_set (&global_variable_set, "");
}
/* Print all the local variables of FILE. */
void
print_file_variables (file)
struct file *file;
{
if (file->variables != 0)
print_variable_set (file->variables->set, "# ");
}
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