From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Wed, 9 Aug 2017 12:04:07 +0000 (+0200)
Subject: shell: more efficient check for EOL in read
X-Git-Tag: 1_28_0~155
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=cde46f75cbe8069e06b68396a7f6dc9564fbf2c4;p=oweals%2Fbusybox.git

shell: more efficient check for EOL in read

function                                             old     new   delta
shell_builtin_read                                  1334    1320     -14

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---

diff --git a/shell/shell_common.c b/shell/shell_common.c
index 2db8ea3e2..7a0799ed5 100644
--- a/shell/shell_common.c
+++ b/shell/shell_common.c
@@ -65,6 +65,7 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
 	int nchars; /* -n NUM */
 	char **pp;
 	char *buffer;
+	char delim;
 	struct termios tty, old_tty;
 	const char *retval;
 	int bufpos; /* need to be able to hold -1 */
@@ -185,6 +186,7 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
 		end_ms += (unsigned)monotonic_ms();
 	buffer = NULL;
 	bufpos = 0;
+	delim = opt_d ? *opt_d : '\n';
 	do {
 		char c;
 		int timeout;
@@ -238,10 +240,7 @@ shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
 				continue;
 			}
 		}
-		if (opt_d) {
-			if (c == *opt_d)
-				break;
-		} else if (c == '\n')
+		if (c == delim) /* '\n' or -d CHAR */
 			break;
 
 		/* $IFS splitting. NOT done if we run "read"
diff --git a/shell/shell_common.h b/shell/shell_common.h
index 1b79bffca..875fd9ea7 100644
--- a/shell/shell_common.h
+++ b/shell/shell_common.h
@@ -34,6 +34,11 @@ enum {
 	BUILTIN_READ_SILENT = 1 << 0,
 	BUILTIN_READ_RAW    = 1 << 1,
 };
+//TODO? do not provide bashisms if not asked for:
+//#if !ENABLE_HUSH_BASH_COMPAT && !ENABLE_ASH_BASH_COMPAT
+//#define shell_builtin_read(setvar,argv,ifs,read_flags,n,p,t,u,d)
+//	shell_builtin_read(setvar,argv,ifs,read_flags)
+//#endif
 const char* FAST_FUNC
 shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
 	char       **argv,