listing: preserve list file on error, include errors

Instead of removing the list file on error, keep the list file and
include the errors in the list file.  This makes it actually possible
to debug things that involve deep macro recursion, where the line
number is pretty much meaningless.

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

3 files changed, 57 insertions, 13 deletions

diff --git a/listing.c b/listing.c
index 97362d0..5a09440 100644
--- a/listing.c
+++ b/listing.c
@@ -65,7 +65,9 @@ static char xdigit[] = "0123456789ABCDEF";
 #define HEX(a,b) (*(a)=xdigit[((b)>>4)&15],(a)[1]=xdigit[(b)&15]);
 
 static char listline[LIST_MAX_LEN];
-static int listlinep;
+static bool listlinep;
+
+static char listerror[LIST_MAX_LEN];
 
 static char listdata[2 * LIST_INDENT];  /* we need less than that actually */
 static int32_t listoffset;
@@ -82,6 +84,8 @@ static FILE *listfp;
 
 static void list_emit(void)
 {
+    int i;
+
     if (!listlinep && !listdata[0])
         return;
 
@@ -105,18 +109,35 @@ static void list_emit(void)
     putc('\n', listfp);
     listlinep = false;
     listdata[0] = '\0';
+
+    if (listerror[0]) {
+	fprintf(listfp, "%6"PRId32"          ", ++listlineno);
+	for (i = 0; i < LIST_HEXBIT; i++)
+	    putc('*', listfp);
+	
+	if (listlevel_e)
+	    fprintf(listfp, " %s<%d>", (listlevel < 10 ? " " : ""),
+		    listlevel_e);
+	else
+	    fprintf(listfp, "     ");
+
+	fprintf(listfp, "  %s\n", listerror);
+	listerror[0] = '\0';
+    }
 }
 
 static void list_init(char *fname, efunc error)
 {
     listfp = fopen(fname, "w");
     if (!listfp) {
-        error(ERR_NONFATAL, "unable to open listing file `%s'", fname);
+        error(ERR_NONFATAL, "unable to open listing file `%s'",
+	      fname);
         return;
     }
 
     *listline = '\0';
     listlineno = 0;
+    *listerror = '\0';
     listp = true;
     listlevel = 0;
     suppress = 0;
@@ -343,11 +364,24 @@ static void list_downlevel(int type)
     }
 }
 
+static void list_error(int severity, const char *pfx, const char *msg)
+{
+    if (!listfp)
+	return;
+
+    snprintf(listerror, sizeof listerror, "%s%s", pfx, msg);
+
+    if ((severity & ERR_MASK) >= ERR_FATAL)
+	list_emit();
+}
+
+
 ListGen nasmlist = {
     list_init,
     list_cleanup,
     list_output,
     list_line,
     list_uplevel,
-    list_downlevel
+    list_downlevel,
+    list_error
 };
diff --git a/nasm.c b/nasm.c
index ceafe51..a938aaa 100644
--- a/nasm.c
+++ b/nasm.c
@@ -474,8 +474,6 @@ int main(int argc, char **argv)
                 fclose (ofile);
 
                 remove(outname);
-                if (listname[0])
-                    remove(listname);
             }
         }
         break;
@@ -1922,28 +1920,36 @@ static bool is_suppressed_warning(int severity)
 static void report_error_common(int severity, const char *fmt,
                                 va_list args)
 {
+    char msg[1024];
+    const char *pfx;
+    
     switch (severity & (ERR_MASK|ERR_NO_SEVERITY)) {
     case ERR_WARNING:
-        fputs("warning: ", error_file);
+        pfx = "warning: ";
         break;
     case ERR_NONFATAL:
-        fputs("error: ", error_file);
+        pfx = "error: ";
         break;
     case ERR_FATAL:
-        fputs("fatal: ", error_file);
+        pfx = "fatal: ";
         break;
     case ERR_PANIC:
-        fputs("panic: ", error_file);
+        pfx = "panic: ";
         break;
     case ERR_DEBUG:
-        fputs("debug: ", error_file);
+        pfx = "debug: ";
         break;
     default:
+	pfx = "";
 	break;
     }
 
-    vfprintf(error_file, fmt, args);
-    putc('\n', error_file);
+    vsnprintf(msg, sizeof msg, fmt, args);
+
+    fprintf(error_file, "%s%s\n", pfx, msg);
+
+    if (*listname)
+	nasmlist.error(severity, pfx, msg);
 
     if (severity & ERR_USAGE)
         want_usage = true;
diff --git a/nasm.h b/nasm.h
index 98823be..0e6482b 100644
--- a/nasm.h
+++ b/nasm.h
@@ -182,6 +182,11 @@ typedef struct {
      * Reverse the effects of uplevel.
      */
     void (*downlevel) (int);
+
+    /*
+     * Called on a warning or error, with the error message.
+     */
+    void (*error)(int severity, const char *pfx, const char *msg);
 } ListGen;
 
 /*
@@ -941,7 +946,6 @@ struct ofmt {
  */
 
 struct dfmt {
-
     /*
      * This is a short (one-liner) description of the type of
      * output generated by the driver.