LXR busybox/scripts/generate

   1#!/bin/sh
   2# Called from top-level directory a-la
   3#
   4# scripts/generate_BUFSIZ.sh include/common_bufsiz.h
   5
   6. ./.config || exit 1
   7
   8debug=false
   9#debug=true
  10
  11postcompile=false
  12test x"$1" = x"--post" && { postcompile=true; shift; }
  13
  14common_bufsiz_h=$1
  15
  16test x"$NM" = x"" && NM="${CONFIG_CROSS_COMPILER_PREFIX}nm"
  17test x"$CC" = x"" && CC="${CONFIG_CROSS_COMPILER_PREFIX}gcc"
  18
  19exitcmd="exit 0"
  20
  21regenerate() {
  22        cat >"$1.$$"
  23        test -f "$1" && diff "$1.$$" "$1" >/dev/null && rm "$1.$$" && return
  24        mv "$1.$$" "$1"
  25}
  26
  27generate_std_and_exit() {
  28        $debug && echo "Configuring: bb_common_bufsiz1[] in bss"
  29        {
  30        echo "enum { COMMON_BUFSIZE = 1024 };"
  31        echo "extern char bb_common_bufsiz1[];"
  32        echo "#define setup_common_bufsiz() ((void)0)"
  33        } | regenerate "$common_bufsiz_h"
  34        echo "std" >"$common_bufsiz_h.method"
  35        $exitcmd
  36}
  37
  38generate_big_and_exit() {
  39        $debug && echo "Configuring: bb_common_bufsiz1[] in bss, COMMON_BUFSIZE = $1"
  40        {
  41        echo "enum { COMMON_BUFSIZE = $1 };"
  42        echo "extern char bb_common_bufsiz1[];"
  43        echo "#define setup_common_bufsiz() ((void)0)"
  44        } | regenerate "$common_bufsiz_h"
  45        echo "$2" >"$common_bufsiz_h.method"
  46        $exitcmd
  47}
  48
  49generate_1k_and_exit() {
  50        generate_big_and_exit 1024 "1k"
  51}
  52
  53round_down_COMMON_BUFSIZE() {
  54        COMMON_BUFSIZE=1024
  55        test "$1" -le 32 && return
  56        COMMON_BUFSIZE=$(( ($1-32) & 0x0ffffff0 ))
  57        COMMON_BUFSIZE=$(( COMMON_BUFSIZE < 1024 ? 1024 : COMMON_BUFSIZE ))
  58}
  59
  60# User does not want any funky stuff?
  61test x"$CONFIG_FEATURE_USE_BSS_TAIL" = x"y" || generate_std_and_exit
  62
  63# The script is run two times: before compilation, when it needs to
  64# (re)generate $common_bufsiz_h, and directly after successful build,
  65# when it needs to assess whether the build is ok to use at all (not buggy),
  66# and (re)generate $common_bufsiz_h for a future build.
  67
  68if $postcompile; then
  69        # Postcompile needs to create/delete OK/FAIL files
  70
  71        test -f busybox_unstripped || exit 1
  72        test -f "$common_bufsiz_h.method" || exit 1
  73
  74        # How the build was done?
  75        method=`cat -- "$common_bufsiz_h.method"`
  76
  77        # Get _end address
  78        END=`$NM busybox_unstripped | grep ' . _end$'| cut -d' ' -f1`
  79        test x"$END" = x"" && generate_std_and_exit
  80        $debug && echo "END:0x$END $((0x$END))"
  81        END=$((0x$END))
  82
  83        # Get PAGE_SIZE
  84        {
  85        echo "#include <sys/user.h>"
  86        echo "#if defined(PAGE_SIZE) && PAGE_SIZE > 0"
  87        echo "char page_size[PAGE_SIZE];"
  88        echo "#endif"
  89        } >page_size_$$.c
  90        $CC -c "page_size_$$.c" || exit 1
  91        PAGE_SIZE=`$NM --size-sort "page_size_$$.o" | cut -d' ' -f1`
  92        rm "page_size_$$.c" "page_size_$$.o"
  93        test x"$PAGE_SIZE" = x"" && exit 1
  94        $debug && echo "PAGE_SIZE:0x$PAGE_SIZE $((0x$PAGE_SIZE))"
  95        PAGE_SIZE=$((0x$PAGE_SIZE))
  96        test $PAGE_SIZE -lt 1024 && exit 1
  97
  98        # How much space between _end[] and next page?
  99        PAGE_MASK=$((PAGE_SIZE-1))
 100        TAIL_SIZE=$(( (-END) & PAGE_MASK ))
 101        $debug && echo "TAIL_SIZE:$TAIL_SIZE bytes"
 102
 103        if test x"$method" = x"1k"; then
 104                {
 105                echo $TAIL_SIZE
 106                md5sum <.config | cut -d' ' -f1
 107                stat -c "%Y" .config
 108                } >"$common_bufsiz_h.1k.OK"
 109                round_down_COMMON_BUFSIZE $((1024 + TAIL_SIZE))
 110                # emit message only if COMMON_BUFSIZE is indeed larger
 111                test $COMMON_BUFSIZE -gt 1024 \
 112                        && echo "Rerun make to use larger COMMON_BUFSIZE ($COMMON_BUFSIZE)"
 113                test $COMMON_BUFSIZE = 1024 && generate_1k_and_exit
 114                generate_big_and_exit $COMMON_BUFSIZE "big"
 115        fi
 116fi
 117
 118# Based on past success/fail of 1k build, decide next build type
 119
 120if test -f "$common_bufsiz_h.1k.OK"; then
 121        # previous 1k build succeeded
 122        oldcfg=`tail -n2 -- "$common_bufsiz_h.1k.OK"`
 123        curcfg=`md5sum <.config | cut -d' ' -f1; stat -c "%Y" .config`
 124        # config did not change
 125        if test x"$oldcfg" = x"$curcfg"; then
 126                # Try bigger COMMON_BUFSIZE if possible
 127                TAIL_SIZE=`head -n1 -- "$common_bufsiz_h.1k.OK"`
 128                round_down_COMMON_BUFSIZE $((1024 + TAIL_SIZE))
 129                test $COMMON_BUFSIZE = 1024 && generate_1k_and_exit
 130                generate_big_and_exit $COMMON_BUFSIZE "big"
 131        fi
 132        # config did change
 133        rm -rf -- "$common_bufsiz_h.1k.OK"
 134fi
 135
 136# There was no 1k build yet. Try it.
 137generate_1k_and_exit
 138