Do not re-set iconv converter state when the input encoding may use

byte-order from a BOM, because some iconv implementations (including
win_iconv, Apple libiconv) forget the byte order on re-set. Partially
reverts 85476.


git-svn-id: https://svn.r-project.org/R/trunk@87222 00db46b3-68df-0310-9c12-caf00c1e9a41

src/gnuwin32/system.c

@@ -460,8 +460,12 @@ FileReadConsole(const char *prompt, unsigned char *buf, int len, int addhistory)
 	err = (res == (size_t)(-1));
 	/* errors lead to part of the input line being ignored */
 	if(err) {
+	    /* Should re-set with a stateful encoding, but some iconv
+	       implementations forget byte-order learned from BOM. 
+
 	    Riconv(cd, NULL, NULL, &ob, &onb);
 	    *ob = '\0';
+	    */
 	    printf(_("<ERROR: re-encoding failure from encoding '%s'>\n"),
 		       R_StdinEnc);
 	}

src/main/sysutils.c

@@ -793,11 +793,16 @@ attribute_hidden SEXP do_iconv(SEXP call, SEXP op, SEXP args, SEXP env)
 		/* it seems this gets thrown for non-convertible input too */
 		/* EINVAL returned for invalid input on macOS with system
 		   libiconv */
+		/*
+		  Should re-set with a stateful encoding, but some iconv
+		  implementations forget byte-order learned from BOM.
+
 		res = Riconv(obj, NULL, NULL, &outbuf, &outb);	
 		if (res == -1 && errno == E2BIG) {
 		    R_AllocStringBuffer(2*cbuff.bufsize, &cbuff);
 		    goto top_of_loop;
-		}	
+		}
+		*/
 		if(fromUTF8 && streql(sub, "Unicode")) {
 		    if(outb < 13) {
 			R_AllocStringBuffer(2*cbuff.bufsize, &cbuff);

src/unix/sys-std.c

@@ -1025,8 +1025,12 @@ Rstd_ReadConsole(const char *prompt, unsigned char *buf, int len,
 	    err = res == (size_t)(-1);
 	    /* errors lead to part of the input line being ignored */
 	    if(err) {
+		/* Should re-set with a stateful encoding, but some iconv
+                   implementations forget byte-order learned from BOM.
+
 		Riconv(cd, NULL, NULL, &ob, &onb);
 		*ob = '\0';
+		*/
 		printf(_("<ERROR: re-encoding failure from encoding '%s'>\n"),
 		       R_StdinEnc);
 		strncpy((char *)buf, obuf, len);