Handle builtin-macros as defined entries in the macro table

Add the necessary infra to pass and carry a function pointer in the macro
entry, define builtins as part of macro initialization and switch
the main expansion loop to use the macro entry info instead of special
builtin lookup.

This has various nice benefits, such as allowing simple testing whether
rpm supports a given primitive by testing whether said macro is defined
and a small performance boost as an extra lookup for the builtins is
eliminated from all macro expansion cycles.
It also paves way for later implementing various spec constructs as
actual macros instead of the confusing pseudo-macros they are now.

Apart from builtins showing up as defined and macro initialization now
being mandatory, this is not supposed to change any concrete behavior.

rpmio/macro.c

@@ -53,6 +53,7 @@ struct rpmMacroEntry_s {
     const char *name;  	/*!< Macro name. */
     const char *opts;  	/*!< Macro parameters (a la getopt) */
     const char *body;	/*!< Macro body. */
+    void *func;		/*!< Macro function (builtin macros) */
     int flags;		/*!< Macro state bits. */
     int level;          /*!< Scoping level. */
     char arena[];   	/*!< String arena. */
@@ -616,7 +617,6 @@ static unsigned int getncpus(void)
 
 #define STR_AND_LEN(_str) (_str), sizeof((_str))-1
 
-/* Names in the table must be in ASCII-code order */
 static struct builtins_s {
     const char * name;
     size_t len;
@@ -651,40 +651,13 @@ static struct builtins_s {
     { STR_AND_LEN("url2path"),	doFoo,		ME_ARGFUNC },
     { STR_AND_LEN("verbose"),	doVerbose,	ME_ARGFUNC },
     { STR_AND_LEN("warn"),	doOutput,	ME_ARGFUNC },
+    { NULL,	0,		NULL,		0 }
 };
-static const size_t numbuiltins = sizeof(builtinmacros)/sizeof(*builtinmacros);
-
-static int namecmp(const void *name1, const void *name2)
-{
-    struct builtins_s *n1 = (struct builtins_s *)name1;
-    struct builtins_s *n2 = (struct builtins_s *)name2;
-
-    int rc = strncmp(n1->name, n2->name, n1->len);
-    if (rc == 0)
-	rc = n1->len - n2->len;
-    return rc;
-}
-
-/**
- * Return a pointer to the built-in macro with the given name
- * @param name		macro name
- * @param nlen		name length
- * @return		pointer to the built-in macro or NULL if not found
- */
-static const struct builtins_s* lookupBuiltin(const char *name, size_t nlen)
-{
-    struct builtins_s macro = {
-	.name = name,
-	.len = nlen,
-    };
-
-    return bsearch(&macro, builtinmacros, numbuiltins, sizeof(*builtinmacros),
-		    namecmp);
-}
 
 static int
 validName(MacroBuf mb, const char *name, size_t namelen, const char *action)
 {
+    rpmMacroEntry *mep;
     int rc = 0;
     int c;
 
@@ -694,7 +667,8 @@ validName(MacroBuf mb, const char *name, size_t namelen, const char *action)
 	goto exit;
     }
 
-    if (lookupBuiltin(name, namelen)) {
+    mep = findEntry(mb->mc, name, namelen, NULL);
+    if (mep && (*mep)->flags & ME_BUILTIN) {
 	mbErr(mb, 1, _("Macro %%%s is a built-in (%s)\n"), name, action);
 	goto exit;
     }
@@ -1411,11 +1385,15 @@ doExpandThisMacro(MacroBuf mb, rpmMacroEntry me, ARGV_t args)
 {
     rpmMacroEntry prevme = mb->me;
     ARGV_t prevarg = mb->args;
+
     /* Setup args for "%name " macros with opts */
     if (args != NULL)
 	setupArgs(mb, me, args);
     /* Recursively expand body of macro */
-    if (me->body && *me->body) {
+    if (me->flags & ME_BUILTIN) {
+	/* XXX not yet */
+	mbErr(mb, 1, "tried to expand a builtin: %s\n", me->name);
+    } else if (me->body && *me->body) {
 	if ((me->flags & ME_LITERAL) != 0)
 	    mbAppendStr(mb, me->body);
 	else
@@ -1468,7 +1446,6 @@ expandMacro(MacroBuf mb, const char *src, size_t slen)
 	goto exit;
 
     while (mb->error == 0 && (c = *s) != '\0') {
-	const struct builtins_s* builtin = NULL;
 	s++;
 	/* Copy text until next macro */
 	switch (c) {
@@ -1554,25 +1531,6 @@ expandMacro(MacroBuf mb, const char *src, size_t slen)
 	if (mb->macro_trace)
 	    printMacro(mb, s, se);
 
-	/* Expand builtin macros */
-	if ((builtin = lookupBuiltin(f, fn))) {
-	    int havearg = (builtin->flags & ME_HAVEARG) ? 1 : 0;
-	    if (havearg != (g != NULL)) {
-		mbErr(mb, 1, "%%%s: %s\n", builtin->name, havearg ?
-			_("argument expected") : _("unexpected argument"));
-		continue;
-	    }
-	    if (builtin->flags & ME_PARSE) {
-		parseFunc parse = builtin->func;
-		s = parse(mb, se);
-	    } else {
-		macroFunc func = builtin->func;
-		func(mb, chkexist, negate, f, fn, g, gn);
-		s = se;
-	    }
-	    continue;
-	}
-
 	/* Expand defined macros */
 	mep = findEntry(mb->mc, f, fn, NULL);
 	me = (mep ? *mep : NULL);
@@ -1587,6 +1545,25 @@ expandMacro(MacroBuf mb, const char *src, size_t slen)
 	    }
 	}
 
+	/* Expand builtin macros */
+	if (me && (me->flags & ME_BUILTIN)) {
+	    int havearg = (me->flags & ME_HAVEARG) ? 1 : 0;
+	    if (havearg != (g != NULL)) {
+		mbErr(mb, 1, "%%%s: %s\n", me->name, havearg ?
+			_("argument expected") : _("unexpected argument"));
+		continue;
+	    }
+	    if (me->flags & ME_PARSE) {
+		parseFunc parse = me->func;
+		s = parse(mb, se);
+	    } else {
+		macroFunc func = me->func;
+		func(mb, chkexist, negate, f, fn, g, gn);
+		s = se;
+	    }
+	    continue;
+	}
+
 	/* XXX Special processing for flags and existance test */
 	if (*f == '-' || chkexist) {
 	    if ((me == NULL && !negate) ||	/* Without existance, skip %{?...} */
@@ -1698,8 +1675,9 @@ static int doExpandMacros(rpmMacroContext mc, const char *src, int flags,
     return rc;
 }
 
-static void pushMacro(rpmMacroContext mc,
+static void pushMacroAny(rpmMacroContext mc,
-	const char * n, const char * o, const char * b, int level, int flags)
+	const char * n, const char * o, const char * b, void * f,
+	int level, int flags)
 {
     /* new entry */
     rpmMacroEntry me;
@@ -1757,6 +1735,7 @@ static void pushMacro(rpmMacroContext mc,
     else
 	me->opts = o ? "" : NULL;
     /* initialize */
+    me->func = f;
     me->flags = flags;
     me->flags &= ~(ME_USED);
     me->level = level;
@@ -1765,6 +1744,12 @@ static void pushMacro(rpmMacroContext mc,
     *mep = me;
 }
 
+static void pushMacro(rpmMacroContext mc,
+	const char * n, const char * o, const char * b, int level, int flags)
+{
+    return pushMacroAny(mc, n, o, b, NULL, level, flags);
+}
+
 static void popMacro(rpmMacroContext mc, const char * n)
 {
     size_t pos;
@@ -2015,6 +2000,12 @@ rpmInitMacros(rpmMacroContext mc, const char * macrofiles)
     rpmMacroContext climc;
     mc = rpmmctxAcquire(mc);
 
+    /* Define built-in macros */
+    for (const struct builtins_s *b = builtinmacros; b->name; b++) {
+	pushMacroAny(mc, b->name, NULL, "<builtin>", b->func,
+			RMIL_BUILTIN, b->flags);
+    }
+
     argvSplit(&globs, macrofiles, ":");
     for (pattern = globs; pattern && *pattern; pattern++) {
 	ARGV_t path, files = NULL;

rpmio/rpmmacro.h

@@ -35,6 +35,7 @@ extern const char * macrofiles;
 /**
  * Markers for sources of macros added throughout rpm.
  */
+#define	RMIL_BUILTIN	-20
 #define	RMIL_DEFAULT	-15
 #define	RMIL_MACROFILES	-13
 #define	RMIL_RPMRC	-11