err.c.patch   [plain text]

--- err.c.orig	2006-12-15 11:18:17.000000000 -0800
+++ err.c	2006-12-15 11:46:52.000000000 -0800
@@ -44,12 +44,85 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <vis.h>
 #include "un-namespace.h"
 
 #include "libc_private.h"
 
-static FILE *err_file; /* file to use for error output */
-static void (*err_exit)(int);
+#ifdef BUILDING_VARIANT
+
+__private_extern__ FILE *_e_err_file; /* file to use for error output */
+__private_extern__ void (*_e_err_exit)(int);
+__private_extern__ void _e_visprintf(FILE * __restrict, const char * __restrict, va_list);
+
+#else /* !BUILDING_VARIANT */
+
+__private_extern__ FILE *_e_err_file = NULL; /* file to use for error output */
+__private_extern__ void (*_e_err_exit)(int) = NULL;
+
+/*
+ * zero means pass as is
+ * 255 means use \nnn (octal)
+ * otherwise use \x (x is value)
+ * (NUL isn't used)
+ */
+static unsigned char escape[256] = {
+     /* NUL  SOH  STX  ETX  EOT  ENQ  ACK  BEL */
+	0  , 255, 255, 255, 255, 255, 255, 'a',
+     /* BS   HT   NL   VT   NP   CR   SO   SI  */
+	'b', 't', 'n', 'v', 'f', 'r', 255, 255,
+     /* DLE  DC1  DC2  DC3  DC4  NAK  SYN  ETB */
+	255, 255, 255, 255, 255, 255, 255, 255,
+     /* CAN  EM   SUB  ESC  FS   GS   RS   US  */
+	255, 255, 255, 255, 255, 255, 255, 255,
+     /* the rest are zero */
+};
+
+/*
+ * Make characters visible.  If we can't allocate enough
+ * memory, we fall back on vfprintf().
+ */
+__private_extern__ void
+_e_visprintf(FILE * __restrict stream, const char * __restrict format, va_list ap)
+{
+	int failed = 0;
+	char *str, *visstr;
+	va_list backup;
+
+	va_copy(backup, ap);
+	vasprintf(&str, format, ap);
+	if (str != NULL) {
+		if ((visstr = malloc(4 * strlen(str) + 1)) != NULL) {
+			unsigned char *fp = (unsigned char *)str;
+			unsigned char *tp = (unsigned char *)visstr;
+			while(*fp) {
+				switch(escape[*fp]) {
+				case 0:
+					*tp++ = *fp;
+					break;
+				case 255:
+					sprintf(tp, "\\%03o", *fp);
+					tp += 4;
+					break;
+				default:
+					*tp++ = '\\';
+					*tp++ = escape[*fp];
+					break;
+				}
+				fp++;
+			}
+			*tp = 0;
+			fputs(visstr, stream);
+			free(visstr);
+		} else
+			failed = 1;
+		free(str);
+	} else
+		failed = 1;
+	if (failed)
+		vfprintf(stream, format, backup);
+	va_end(backup);
+}
 
 /*
  * This is declared to take a `void *' so that the caller is not required
@@ -60,16 +133,17 @@
 err_set_file(void *fp)
 {
 	if (fp)
-		err_file = fp;
+		_e_err_file = fp;
 	else
-		err_file = stderr;
+		_e_err_file = stderr;
 }
 
 void
 err_set_exit(void (*ef)(int))
 {
-	err_exit = ef;
+	_e_err_exit = ef;
 }
+#endif /* !BUILDING_VARIANT */
 
 __weak_reference(_err, err);
 
@@ -107,16 +181,16 @@
 	const char *fmt;
 	va_list ap;
 {
-	if (err_file == 0)
+	if (_e_err_file == 0)
 		err_set_file((FILE *)0);
-	fprintf(err_file, "%s: ", _getprogname());
+	fprintf(_e_err_file, "%s: ", _getprogname());
 	if (fmt != NULL) {
-		vfprintf(err_file, fmt, ap);
-		fprintf(err_file, ": ");
+		_e_visprintf(_e_err_file, fmt, ap);
+		fprintf(_e_err_file, ": ");
 	}
-	fprintf(err_file, "%s\n", strerror(code));
-	if (err_exit)
-		err_exit(eval);
+	fprintf(_e_err_file, "%s\n", strerror(code));
+	if (_e_err_exit)
+		_e_err_exit(eval);
 	exit(eval);
 }
 
@@ -135,14 +209,14 @@
 	const char *fmt;
 	va_list ap;
 {
-	if (err_file == 0)
+	if (_e_err_file == 0)
 		err_set_file((FILE *)0);
-	fprintf(err_file, "%s: ", _getprogname());
+	fprintf(_e_err_file, "%s: ", _getprogname());
 	if (fmt != NULL)
-		vfprintf(err_file, fmt, ap);
-	fprintf(err_file, "\n");
-	if (err_exit)
-		err_exit(eval);
+		_e_visprintf(_e_err_file, fmt, ap);
+	fprintf(_e_err_file, "\n");
+	if (_e_err_exit)
+		_e_err_exit(eval);
 	exit(eval);
 }
 
@@ -180,14 +254,14 @@
 	const char *fmt;
 	va_list ap;
 {
-	if (err_file == 0)
+	if (_e_err_file == 0)
 		err_set_file((FILE *)0);
-	fprintf(err_file, "%s: ", _getprogname());
+	fprintf(_e_err_file, "%s: ", _getprogname());
 	if (fmt != NULL) {
-		vfprintf(err_file, fmt, ap);
-		fprintf(err_file, ": ");
+		_e_visprintf(_e_err_file, fmt, ap);
+		fprintf(_e_err_file, ": ");
 	}
-	fprintf(err_file, "%s\n", strerror(code));
+	fprintf(_e_err_file, "%s\n", strerror(code));
 }
 
 void
@@ -204,10 +278,10 @@
 	const char *fmt;
 	va_list ap;
 {
-	if (err_file == 0)
+	if (_e_err_file == 0)
 		err_set_file((FILE *)0);
-	fprintf(err_file, "%s: ", _getprogname());
+	fprintf(_e_err_file, "%s: ", _getprogname());
 	if (fmt != NULL)
-		vfprintf(err_file, fmt, ap);
-	fprintf(err_file, "\n");
+		_e_visprintf(_e_err_file, fmt, ap);
+	fprintf(_e_err_file, "\n");
 }