labels: global/common/extern/static can now force the external name

Add an option to the global/common/extern/static directives to force
the external name to be used for a label.  The syntax is:

	GLOBAL symbol "external_name" ...

where "external_name" is any NASM quoted string without control
characters.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>

asm/directiv.c

@@ -55,6 +55,7 @@
 #include "listing.h"
 #include "labels.h"
 #include "iflag.h"
+#include "quote.h"
 
 struct cpunames {
     const char *name;
@@ -314,9 +315,11 @@ bool process_directives(char *directive)
     {
         bool validid = true;
         int64_t size = 0;
-        char *sizestr;
+        char *mangled, *sizestr;
         bool rn_error;
 
+        mangled = sizestr = NULL;
+
         if (*value == '$')
             value++;        /* skip initial $ if present */
 
@@ -340,10 +343,18 @@ bool process_directives(char *directive)
 
         if (nasm_isspace(*q)) {
             *q++ = '\0';
+            q = nasm_skip_spaces(q);
+            if (isquote(*q)) {
+                mangled = q;
+                q = nasm_unquote_cstr(q, directive);
+                if (nasm_isspace(*q))
+                    q = nasm_skip_spaces(q);
+            }
+        }
+
+        if (*q && *q != ':') {
             sizestr = q = nasm_skip_spaces(q);
             q = strchr(q, ':');
-        } else {
-            sizestr = NULL;
         }
 
         if (q && *q == ':') {
@@ -365,13 +376,13 @@ bool process_directives(char *directive)
                        directive);
         }
 
-        if (!declare_label(value, type, special))
+        if (!declare_label(value, type, mangled, special))
             break;
-        
+
         if (type == LBL_COMMON || type == LBL_EXTERN)
             define_label(value, 0, size, false);
 
-    	break;
+	break;
     }
 
     case D_ABSOLUTE:        /* [ABSOLUTE address] */

asm/labels.c

@@ -305,7 +305,8 @@ static const char *mangle_label_name(union label *lptr)
     const char *suffix;
 
     if (likely(lptr->defn.mangled &&
-               lptr->defn.mangled_type == lptr->defn.type))
+               (lptr->defn.mangled_type == lptr->defn.type ||
+                lptr->defn.mangled_type == LBL_SPECIAL)))
         return lptr->defn.mangled; /* Already mangled */
 
     switch (lptr->defn.type) {
@@ -363,12 +364,23 @@ handle_herelabel(union label *lptr, int32_t *segment, int64_t *offset)
     }
 }
 
-static bool declare_label_lptr(union label *lptr,
-                               enum label_type type, const char *special)
+static bool declare_label_lptr(union label *lptr, enum label_type type,
+                               const char *mangled, const char *special)
 {
     if (special && !special[0])
         special = NULL;
 
+    if (mangled) {
+        if (lptr->defn.mangled && lptr->defn.mangled_type == LBL_SPECIAL) {
+            if (strcmp(lptr->defn.mangled, mangled))
+                nasm_error(ERR_NONFATAL, "symbol `%s' has inconsistent external names: `%s' and `%s'",
+                           lptr->defn.label, lptr->defn.mangled, mangled);
+        } else {
+            lptr->defn.mangled = perm_copy(mangled);
+            lptr->defn.mangled_type = LBL_SPECIAL; /* Forced manually */
+        }
+    }
+
     if (lptr->defn.type == type ||
         (pass0 == 0 && lptr->defn.type == LBL_LOCAL)) {
         lptr->defn.type = type;
@@ -407,13 +419,14 @@ static bool declare_label_lptr(union label *lptr,
     return false;
 }
 
-bool declare_label(const char *label, enum label_type type, const char *special)
+bool declare_label(const char *label, enum label_type type,
+                   const char *mangled, const char *special)
 {
     union label *lptr;
     bool created;
 
     lptr = find_label(label, true, &created);
-    return declare_label_lptr(lptr, type, special);
+    return declare_label_lptr(lptr, type, mangled, special);
 }
 
 /*
@@ -491,7 +504,7 @@ void define_label(const char *label, int32_t segment,
  */
 void backend_label(const char *label, int32_t segment, int64_t offset)
 {
-    if (!declare_label(label, LBL_BACKEND, NULL))
+    if (!declare_label(label, LBL_BACKEND, NULL, NULL))
         return;
 
     define_label(label, segment, offset, false);

include/labels.h

@@ -63,7 +63,7 @@ void define_label(const char *label, int32_t segment, int64_t offset,
                   bool normal);
 void backend_label(const char *label, int32_t segment, int64_t offset);
 bool declare_label(const char *label, enum label_type type,
-                   const char *special);
+                   const char *mangled, const char *special);
 void set_label_mangle(enum mangle_index which, const char *what);
 int init_labels(void);
 void cleanup_labels(void);

test/ctxlocal.asm

@@ -19,7 +19,7 @@ here:
 everywhere:
 	ret
 
-	global everywhere
+	global everywhere "hejsan"
 
 tjosan:
 	ret