error: replace nasm_verror() indirection with preproc callback

Since pp_error_list_macros() was introduced, the only need for
pp_verror() is to suppress error messages in certain contexts. Replace
this function with a preprocessor callback,
preproc->pp_suppress_error(), so we can drop the nasm_verror()
function pointer entirely.

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

asm/error.c

@@ -41,12 +41,6 @@
 #include "nasmlib.h"
 #include "error.h"
 
-/*
- * Global error handling function. If we call this before it is
- * initialized, it is a fatal error!
- */
-vefunc nasm_verror = (vefunc)nasm_verror_critical;
-
 /* Common function body */
 #define nasm_do_error(_sev,_flags)				\
 	va_list ap;						\

asm/nasm.c

@@ -74,7 +74,6 @@ const char *_progname;
 static void parse_cmdline(int, char **, int);
 static void assemble_file(const char *, struct strlist *);
 static bool skip_this_pass(errflags severity);
-static void nasm_verror_asm(errflags severity, const char *fmt, va_list args);
 static void usage(void);
 static void help(FILE *);
 
@@ -474,7 +473,6 @@ int main(int argc, char **argv)
 {
     /* Do these as early as possible */
     error_file = stderr;
-    nasm_set_verror(nasm_verror_asm);
     _progname = argv[0];
     if (!_progname || !_progname[0])
         _progname = "nasm";
@@ -1774,7 +1772,13 @@ static bool is_suppressed(errflags severity)
     if ((severity & ERR_UNDEAD) && terminate_after_phase)
         return true;
 
-    return !(warning_state[warn_index(severity)] & WARN_ST_ENABLED);
+    if (!(warning_state[warn_index(severity)] & WARN_ST_ENABLED))
+        return true;
+
+    if (preproc && !(severity & ERR_PP_LISTMACRO))
+        return preproc->suppress_error(severity);
+
+    return false;
 }
 
 /**
@@ -1886,7 +1890,7 @@ fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list args
  * @param severity the severity of the warning or error
  * @param fmt the printf style format string
  */
-static void nasm_verror_asm(errflags severity, const char *fmt, va_list args)
+void nasm_verror(errflags severity, const char *fmt, va_list args)
 {
     char msg[1024];
     char warnsuf[64];

asm/preproc-nop.c

@@ -182,6 +182,12 @@ static void nop_error_list_macros(errflags severity)
     (void)severity;
 }
 
+static bool nop_suppress_error(errflags severity)
+{
+    (void)severity;
+    return false;
+}
+
 const struct preproc_ops preproc_nop = {
     nop_init,
     nop_reset,
@@ -195,4 +201,5 @@ const struct preproc_ops preproc_nop = {
     nop_pre_command,
     nop_include_path,
     nop_error_list_macros,
+    nop_suppress_error
 };

asm/preproc.c

@@ -515,8 +515,6 @@ static Token *expand_id(Token * tline);
 static Context *get_ctx(const char *name, const char **namep);
 static Token *make_tok_num(int64_t val);
 static Token *make_tok_qstr(const char *str);
-static void pp_verror(errflags severity, const char *fmt, va_list ap);
-static vefunc real_verror;
 static void *new_Block(size_t size);
 static void delete_Blocks(void);
 static Token *new_Token(Token * next, enum pp_token_type type,
@@ -5543,10 +5541,11 @@ static int expand_mmacro(Token * tline)
 }
 
 /*
- * This function adds macro names to error messages, and suppresses
- * them if necessary.
+ * This function decides if an error message should be suppressed.
+ * It will never be called with a severity level of ERR_FATAL or
+ * higher.
  */
-static void pp_verror(errflags severity, const char *fmt, va_list arg)
+static bool pp_suppress_error(errflags severity)
 {
     /*
      * If we're in a dead branch of IF or something like it, ignore the error.
@@ -5555,32 +5554,13 @@ static void pp_verror(errflags severity, const char *fmt, va_list arg)
      *   %if 0 ... %else trailing garbage ... %endif
      * So %else etc should set the ERR_PP_PRECOND flag.
      */
-    if ((severity & ERR_MASK) < ERR_FATAL &&
-	istk && istk->conds &&
+    if (istk && istk->conds &&
 	((severity & ERR_PP_PRECOND) ?
 	 istk->conds->state == COND_NEVER :
 	 !emitting(istk->conds->state)))
-	return;
+        return true;
 
-    /* This doesn't make sense with the macro stack unwinding */
-    if (0) {
-        int32_t delta = 0;
-
-        /* get %macro name */
-        if (!(severity & ERR_NOFILE) && istk && istk->mstk.mmac) {
-            MMacro *mmac = istk->mstk.mmac;
-            char *buf;
-
-            nasm_set_verror(real_verror);
-            buf = nasm_vasprintf(fmt, arg);
-            nasm_error(severity, "(%s:%"PRId32") %s",
-                       mmac->name, mmac->lineno - delta, buf);
-            nasm_set_verror(pp_verror);
-            nasm_free(buf);
-            return;
-        }
-    }
-    real_verror(severity, fmt, arg);
+    return false;
 }
 
 static Token *
@@ -6014,8 +5994,6 @@ static char *pp_getline(void)
     char *line = NULL;
     Token *tline;
 
-    real_verror = nasm_set_verror(pp_verror);
-
     while (true) {
         tline = pp_tokline();
         if (tline == &tok_pop) {
@@ -6041,14 +6019,11 @@ static char *pp_getline(void)
         nasm_free(buf);
     }
 
-    nasm_set_verror(real_verror);
     return line;
 }
 
 static void pp_cleanup_pass(void)
 {
-    real_verror = nasm_set_verror(pp_verror);
-
     if (defining) {
         if (defining->name) {
             nasm_nonfatal("end of file while still defining macro `%s'",
@@ -6061,8 +6036,6 @@ static void pp_cleanup_pass(void)
         defining = NULL;
     }
 
-    nasm_set_verror(real_verror);
-
     while (cstk)
         ctx_pop();
     free_macros();
@@ -6114,8 +6087,6 @@ static void pp_pre_define(char *definition)
     Line *l;
     char *equals;
 
-    real_verror = nasm_set_verror(pp_verror);
-
     equals = strchr(definition, '=');
     space = new_Token(NULL, TOK_WHITESPACE, NULL, 0);
     def = new_Token(space, TOK_PREPROC_ID, "%define", 0);
@@ -6134,8 +6105,6 @@ static void pp_pre_define(char *definition)
     l->first = def;
     l->finishes = NULL;
     predef = l;
-
-    nasm_set_verror(real_verror);
 }
 
 static void pp_pre_undefine(char *definition)
@@ -6249,4 +6218,5 @@ const struct preproc_ops nasmpp = {
     pp_pre_command,
     pp_include_path,
     pp_error_list_macros,
+    pp_suppress_error
 };

disasm/ndisasm.c

@@ -1,5 +1,5 @@
 /* ----------------------------------------------------------------------- *
- *   
+ *
  *   Copyright 1996-2009 The NASM Authors - All Rights Reserved
  *   See the file AUTHORS included with the NASM distribution for
  *   the specific copyright holders.
@@ -14,7 +14,7 @@
  *     copyright notice, this list of conditions and the following
  *     disclaimer in the documentation and/or other materials provided
  *     with the distribution.
- *     
+ *
  *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
@@ -65,18 +65,19 @@ static const char *help =
 static void output_ins(uint64_t, uint8_t *, int, char *);
 static void skip(uint32_t dist, FILE * fp);
 
-fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list val)
+void nasm_verror(errflags severity, const char *fmt, va_list val)
 {
+    severity &= ERR_MASK;
+
     vfprintf(stderr, fmt, val);
-    exit((severity & ERR_MASK) - ERR_FATAL + 2);
+    if (severity >= ERR_FATAL)
+        exit(severity - ERR_FATAL + 1);
 }
 
-static void ndisasm_verror(errflags severity, const char *fmt, va_list val)
+fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list val)
 {
-    if ((severity & ERR_MASK) >= ERR_FATAL)
-        nasm_verror_critical(severity, fmt, val);
-    else
-        vfprintf(stderr, fmt, val);
+    nasm_verror(severity, fmt, val);
+    abort();
 }
 
 int main(int argc, char **argv)
@@ -97,7 +98,6 @@ int main(int argc, char **argv)
     FILE *fp;
 
     nasm_ctype_init();
-    nasm_set_verror(ndisasm_verror);
     iflag_clear_all(&prefer);
 
     offset = 0;

include/error.h

@@ -72,17 +72,9 @@ fatal_func printf_func(2, 3) nasm_panicf(errflags flags, const char *fmt, ...);
 fatal_func nasm_panic_from_macro(const char *file, int line);
 #define panic() nasm_panic_from_macro(__FILE__, __LINE__);
 
-typedef void (*vefunc) (errflags severity, const char *fmt, va_list ap);
-extern vefunc nasm_verror;
+void nasm_verror(errflags severity, const char *fmt, va_list ap);
 fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list ap);
 
-static inline vefunc nasm_set_verror(vefunc ve)
-{
-	vefunc old_verror = nasm_verror;
-	nasm_verror = ve;
-	return old_verror;
-}
-
 /*
  * These are the error severity codes which get passed as the first
  * argument to an efunc.

include/nasm.h

@@ -391,6 +391,9 @@ struct preproc_ops {
 
     /* Unwind the macro stack when printing an error message */
     void (*error_list_macros)(errflags severity);
+
+    /* Return true if an error message should be suppressed */
+    bool (*suppress_error)(errflags severity);
 };
 
 extern const struct preproc_ops nasmpp;

rdoff/rdoff.c

@@ -228,23 +228,24 @@ int rdf_errno = 0;
 /* ========================================================================
  * Hook for nasm_error() to work
  * ======================================================================== */
-fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list val)
+void nasm_verror(errflags severity, const char *fmt, va_list val)
 {
+    severity &= ERR_MASK;
+
     vfprintf(stderr, fmt, val);
-    exit((severity & ERR_MASK) - ERR_FATAL + 2);
+    if (severity >= ERR_FATAL)
+        exit(severity - ERR_FATAL + 1);
 }
 
-static void rdoff_verror(errflags severity, const char *fmt, va_list val)
+fatal_func nasm_verror_critical(errflags severity, const char *fmt, va_list val)
 {
-    if ((severity & ERR_MASK) >= ERR_FATAL)
-        nasm_verror_critical(severity, fmt, val);
-    else
-        vfprintf(stderr, fmt, val);
+    nasm_verror(severity, fmt, val);
+    abort();
 }
 
 void rdoff_init(void)
 {
-    nasm_set_verror(rdoff_verror);
+
 }
 
 /* ========================================================================