[src/trunk]: src/usr.bin/indent indent: make lex_char_or_string simpler

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/441ee8c63a76
branches:  trunk
changeset: 1023739:441ee8c63a76
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sat Sep 25 10:24:10 2021 +0000

description:
indent: make lex_char_or_string simpler

The previous code was so tricky that every second line needed a comment
that explains what's going on.  Replace the complicated code with the
usual straight-forward string-copying patterns.

No functional change.

diffstat:

 usr.bin/indent/lexi.c |  40 +++++++++++++++++-----------------------
 1 files changed, 17 insertions(+), 23 deletions(-)

diffs (61 lines):

diff -r 16ac97c8c6f9 -r 441ee8c63a76 usr.bin/indent/lexi.c
--- a/usr.bin/indent/lexi.c     Sat Sep 25 09:52:21 2021 +0000
+++ b/usr.bin/indent/lexi.c     Sat Sep 25 10:24:10 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: lexi.c,v 1.51 2021/09/25 08:23:31 rillig Exp $ */
+/*     $NetBSD: lexi.c,v 1.52 2021/09/25 10:24:10 rillig Exp $ */
 
 /*-
  * SPDX-License-Identifier: BSD-4-Clause
@@ -46,7 +46,7 @@
 #include <sys/cdefs.h>
 #ifndef lint
 #if defined(__NetBSD__)
-__RCSID("$NetBSD: lexi.c,v 1.51 2021/09/25 08:23:31 rillig Exp $");
+__RCSID("$NetBSD: lexi.c,v 1.52 2021/09/25 10:24:10 rillig Exp $");
 #elif defined(__FreeBSD__)
 __FBSDID("$FreeBSD: head/usr.bin/indent/lexi.c 337862 2018-08-15 18:19:45Z pstef $");
 #endif
@@ -319,27 +319,21 @@
 static void
 lex_char_or_string(void)
 {
-    char delim;
-
-    delim = *token.s;
-    do {                       /* copy the string */
-       for (;;) {              /* move one character or [/<char>]<char> */
-           if (*buf_ptr == '\n') {
-               diag(1, "Unterminated literal");
-               return;
-           }
-           check_size_token(2);
-           *token.e = inbuf_next();
-           if (*token.e == '\\') {     /* if escape, copy extra char */
-               if (*buf_ptr == '\n')   /* check for escaped newline */
-                   ++line_no;
-               *++token.e = inbuf_next();
-               ++token.e;      /* we must increment this again because we
-                                * copied two chars */
-           } else
-               break;          /* we copied one character */
-       }                       /* end of while (1) */
-    } while (*token.e++ != delim);
+    for (char delim = *token.s;;) {
+       if (*buf_ptr == '\n') {
+           diag(1, "Unterminated literal");
+           return;
+       }
+       check_size_token(2);
+       *token.e++ = inbuf_next();
+       if (token.e[-1] == delim)
+           return;
+       if (token.e[-1] == '\\') {
+           if (*buf_ptr == '\n')
+               ++line_no;
+           *token.e++ = inbuf_next();
+       }
+    }
 }
 
 /* Reads the next token, placing it in the global variable "token". */