Add support for .VARIABLES, to which I have use.

This is an extension but also exists in gnu-make.
okay millert@, kn@, thfr@
(I've added an XXX comment on top of the patch you've seen,
no actual further code change)

diff --git a/usr.bin/make/var.c b/usr.bin/make/var.c
index 906f885..5ae52dd 100644 (file)
--- a/usr.bin/make/var.c
+++ b/usr.bin/make/var.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: var.c,v 1.104 2022/06/09 13:13:14 espie Exp $ */
+/*     $OpenBSD: var.c,v 1.105 2023/08/10 10:52:43 espie Exp $ */
 /*     $NetBSD: var.c,v 1.18 1997/03/18 19:24:46 christos Exp $        */
 
 /*
@@ -104,6 +104,8 @@ static char varNoError[] = "";
 bool           errorIsOkay;
 static bool    checkEnvFirst;  /* true if environment should be searched for
                                 * variables before the global context */
+                               /* do we need to recompute varname_list */
+static bool    varname_list_changed = true;
 
 void
 Var_setCheckEnvFirst(bool yes)
@@ -222,6 +224,7 @@ typedef struct Var_ {
 #define VAR_FROM_ENV   8       /* Special source: environment */
 #define VAR_SEEN_ENV   16      /* No need to go look up environment again */
 #define VAR_IS_SHELL   32      /* Magic behavior */
+#define VAR_IS_NAMES   1024    /* Very expensive, only defined when needed */
 /* XXX there are also some flag values which are part of the visible API
  * and thus defined inside var.h, don't forget to look there if you want
  * to define some new flags !
@@ -231,6 +234,8 @@ typedef struct Var_ {
        char name[1];           /* the variable's name */
 }  Var;
 
+/* for GNU make compatibility */
+#define VARNAME_LIST ".VARIABLES"
 
 static struct ohash_info var_info = {
        offsetof(Var, name),
@@ -245,10 +250,11 @@ static void fill_from_env(Var *);
 static Var *create_var(const char *, const char *);
 static void var_set_initial_value(Var *, const char *);
 static void var_set_value(Var *, const char *);
-#define var_get_value(v)       ((v)->flags & VAR_EXEC_LATER ? \
-       var_exec_cmd(v) : \
-       Buf_Retrieve(&((v)->val)))
-static char *var_exec_cmd(Var *);
+static char *var_get_value(Var *);
+static void var_exec_cmd(Var *);
+static void varname_list_retrieve(Var *);
+
+
 static void var_append_value(Var *, const char *);
 static void poison_check(Var *);
 static void var_set_append(const char *, const char *, const char *, int, bool);
@@ -423,6 +429,7 @@ var_set_initial_value(Var *v, const char *val)
        len = strlen(val);
        Buf_Init(&(v->val), len+1);
        Buf_AddChars(&(v->val), len, val);
+       varname_list_changed = true;
 }
 
 /* Normal version of var_set_value(), to be called after variable is fully
@@ -440,6 +447,16 @@ var_set_value(Var *v, const char *val)
        }
 }
 
+static char *
+var_get_value(Var *v)
+{
+       if (v->flags & VAR_IS_NAMES)
+               varname_list_retrieve(v);
+       else if (v->flags & VAR_EXEC_LATER)
+               var_exec_cmd(v);
+       return Buf_Retrieve(&(v->val));
+}
+
 /* Add to a variable, insert a separating space if the variable was already
  * defined.
  */
@@ -628,6 +645,7 @@ Var_Deletei(const char *name, const char *ename)
 
        ohash_remove(&global_variables, slot);
        delete_var(v);
+       varname_list_changed = true;
 }
 
 /* Set or add a global variable, either to VAR_CMD or VAR_GLOBAL.
@@ -687,7 +705,7 @@ Var_Appendi_with_ctxt(const char *name, const char *ename, const char *val,
        var_set_append(name, ename, val, ctxt, true);
 }
 
-static char *
+static void
 var_exec_cmd(Var *v)
 {
        char *arg = Buf_Retrieve(&(v->val));
@@ -699,7 +717,30 @@ var_exec_cmd(Var *v)
        var_set_value(v, res1);
        free(res1);
        v->flags &= ~VAR_EXEC_LATER;
-       return Buf_Retrieve(&(v->val));
+}
+
+static void
+varname_list_retrieve(Var *v)
+{
+       unsigned int i;
+       void *e;
+       bool first = true;
+
+       if (!varname_list_changed)
+               return;
+       for (e = ohash_first(&global_variables, &i); e != NULL;
+           e = ohash_next(&global_variables, &i)) {
+               Var *v2 = e;
+               if (v2->flags & VAR_DUMMY)
+                       continue;
+
+               if (first)
+                       var_set_value(v, v2->name);
+               else
+                       var_append_value(v, v2->name);
+               first = false;
+       }
+       varname_list_changed = false;
 }
 
 /* XXX different semantics for Var_Valuei() and Var_Definedi():
@@ -1339,6 +1380,22 @@ set_magic_shell_variable()
        v->flags = VAR_IS_SHELL | VAR_SEEN_ENV;
 }
 
+static void
+set_magic_name_list_variable()
+{
+       const char *name = VARNAME_LIST;
+       const char *ename = NULL;
+       uint32_t k;
+       Var *v;
+
+       k = ohash_interval(name, &ename);
+       v = find_global_var_without_env(name, ename, k);
+       /* XXX We need to set a "dummy" value because that variable can't be
+        * VAR_DUMMY, since we wouldn't hit var_get_value otherwise.
+        */
+       var_set_initial_value(v, "");
+       v->flags = VAR_IS_NAMES;
+}
 /*
  * Var_Init
  *     Initialize the module
@@ -1348,11 +1405,10 @@ Var_Init(void)
 {
        ohash_init(&global_variables, 10, &var_info);
        set_magic_shell_variable();
-
+       set_magic_name_list_variable();
 
        errorIsOkay = true;
        Var_setCheckEnvFirst(false);
-
        VarModifiers_Init();
        Buf_Init(&subst_buffer, MAKE_BSIZE);
 }