[src/trunk]: src Replace use of errlist with a single concatenated version an...

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

details:   https://anonhg.NetBSD.org/src/rev/597a4c96d739
branches:  trunk
changeset: 759806:597a4c96d739
user:      joerg <joerg%NetBSD.org@localhost>
date:      Thu Dec 16 22:52:32 2010 +0000

description:
Replace use of errlist with a single concatenated version and an offset
array. This requires less storage and avoids one runtime relocation per
errno value.

diffstat:

 lib/libc/gen/errlist.awk    |  39 +++++++++++++++++++++++++++++++++------
 libexec/ld.elf_so/Makefile  |  12 ++++++++++--
 libexec/ld.elf_so/xprintf.c |  10 ++++++----
 3 files changed, 49 insertions(+), 12 deletions(-)

diffs (139 lines):

diff -r b101e2f73f0e -r 597a4c96d739 lib/libc/gen/errlist.awk
--- a/lib/libc/gen/errlist.awk  Thu Dec 16 22:47:27 2010 +0000
+++ b/lib/libc/gen/errlist.awk  Thu Dec 16 22:52:32 2010 +0000
@@ -1,5 +1,5 @@
 #! /usr/bin/awk -f
-#      $NetBSD: errlist.awk,v 1.3 2010/12/12 22:34:44 joerg Exp $
+#      $NetBSD: errlist.awk,v 1.4 2010/12/16 22:52:32 joerg Exp $
 #
 # Copyright (c) 2010 The NetBSD Foundation, Inc.
 # All rights reserved.
@@ -37,6 +37,8 @@
 #
 function tabs(desc) {
        l = length(desc) + 3;
+       if (concat)
+               l++
        if (l < 16)
                return "\t\t\t\t";
        else if (l < 24)
@@ -50,14 +52,25 @@
 }
 function perror(name, number, desc)
 {
-       printf("\t\"%s\",%s/* %d - %s */\n", desc, tabs(desc), number, name);
+       if (!concat) {
+               printf("\t\"%s\",%s/* %d - %s */\n", desc, tabs(desc), number, name);
+       } else {
+               offsets[number] = offset;
+               offset += length(desc) + 1;
+               printf("\t\"%s\\0\"%s/* %d - %s */\n", desc, tabs(desc), number, name);
+       }
 }
 BEGIN {
        printf("/* Automatically generated file; do not edit */\n");
        printf("#include <sys/cdefs.h>\n");
-       printf("__RCSID(\"$NetBSD: errlist.awk,v 1.3 2010/12/12 22:34:44 joerg Exp $\");\n");
+       printf("__RCSID(\"$NetBSD: errlist.awk,v 1.4 2010/12/16 22:52:32 joerg Exp $\");\n");
        printf("#include <errno.h>\n");
-       printf("static const char *const errlist[] = {\n");
+       if (!concat) {
+               printf("static const char *const errlist[] = {\n");
+       } else {
+               printf("static const char concat_errlist[] = {\n");
+               offset = 0;
+       }
        perror("ENOERROR", 0, "Undefined error: 0");
        errno = 1;
 }
@@ -81,6 +94,20 @@
 }
 END {
        printf("};\n\n");
-       printf("const int sys_nerr = sizeof(errlist) / sizeof(errlist[0]);\n");
-       printf("const char * const *sys_errlist = errlist;\n");
+       if (!concat) {
+               printf("const int sys_nerr = sizeof(errlist) / sizeof(errlist[0]);\n");
+               printf("const char * const *sys_errlist = errlist;\n");
+       } else {
+               printf("static const int concat_nerr = %d;\n", errno);
+               printf("static const unsigned short concat_offset[] = {\n");
+               offsets[errno++] = offset;
+               for (j = 0; j < errno; j++) {
+                       printf("\t%d,\n", offsets[j]);
+               }
+               printf("};\n");
+               if (offset > 65535) {
+                       printf("Total errlist size doesn't fit into 16bit\n") > "/dev/stderr";
+                       exit(1);
+               }
+       }
 }
diff -r b101e2f73f0e -r 597a4c96d739 libexec/ld.elf_so/Makefile
--- a/libexec/ld.elf_so/Makefile        Thu Dec 16 22:47:27 2010 +0000
+++ b/libexec/ld.elf_so/Makefile        Thu Dec 16 22:52:32 2010 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: Makefile,v 1.100 2010/12/16 22:47:27 joerg Exp $
+#      $NetBSD: Makefile,v 1.101 2010/12/16 22:52:32 joerg Exp $
 #
 # NOTE: when changing ld.so, ensure that ldd still compiles.
 #
@@ -69,10 +69,18 @@
 .PATH.c: ${NETBSDSRCDIR}/lib/libc/stdlib
 SRCS+=         exit.c
 
+errlist_concat.h: ${NETBSDSRCDIR}/lib/libc/gen/errlist.awk ${NETBSDSRCDIR}/sys/sys/errno.h
+       ${TOOL_AWK} -v concat=1 -f ${.ALLSRC} > ${.TARGET}.tmp && \
+       mv -f ${.TARGET}.tmp ${.TARGET}
+
+xprintf.c: errlist_concat.h
+
+CLEANFILES+=   errlist_concat.h
+
 BINDIR=                ${SHLINKINSTALLDIR}
 
 CPPFLAGS+=     -DLIBDIR=\"${LIBDIR}\" -D_PATH_RTLD=\"${BINDIR}/${PROG}\"
-CPPFLAGS+=     -I${.CURDIR}
+CPPFLAGS+=     -I${.CURDIR} -I.
 CPPFLAGS+=     -DRTLD_LOADER
 CPPFLAGS+=     -D_RTLD_SOURCE
 CPPFLAGS+=     -DCOMBRELOC
diff -r b101e2f73f0e -r 597a4c96d739 libexec/ld.elf_so/xprintf.c
--- a/libexec/ld.elf_so/xprintf.c       Thu Dec 16 22:47:27 2010 +0000
+++ b/libexec/ld.elf_so/xprintf.c       Thu Dec 16 22:52:32 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: xprintf.c,v 1.20 2009/05/19 20:44:52 christos Exp $     */
+/*     $NetBSD: xprintf.c,v 1.21 2010/12/16 22:52:32 joerg Exp $        */
 
 /*
  * Copyright 1996 Matt Thomas <matt%3am-software.com@localhost>
@@ -29,7 +29,7 @@
 
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: xprintf.c,v 1.20 2009/05/19 20:44:52 christos Exp $");
+__RCSID("$NetBSD: xprintf.c,v 1.21 2010/12/16 22:52:32 joerg Exp $");
 #endif /* not lint */
 
 #include <string.h>
@@ -243,16 +243,18 @@
        va_end(ap);
 }
 
+#include "errlist_concat.h"
+
 const char *
 xstrerror(int error)
 {
 
-       if (error >= sys_nerr || error < 0) {
+       if (error >= concat_nerr || error < 0) {
                static char buf[128];
                xsnprintf(buf, sizeof(buf), "Unknown error: %d", error);
                return buf;
        }
-       return sys_errlist[error];
+       return concat_errlist + concat_offset[error];
 }
 
 void