dhcp: tweak comments, no code changes

[oweals/busybox.git] / scripts / generate_BUFSIZ.sh

diff --git a/scripts/generate_BUFSIZ.sh b/scripts/generate_BUFSIZ.sh
index 8aa0174a6bf0d6e8c5a82ce3f0f838394154c180..718788e0b7af1b9ee94b12a1c851fbc039d93d78 100755 (executable)
--- a/scripts/generate_BUFSIZ.sh
+++ b/scripts/generate_BUFSIZ.sh
@@ -6,6 +6,7 @@
 . ./.config || exit 1
 
 debug=false
+#debug=true
 
 postcompile=false
 test x"$1" = x"--post" && { postcompile=true; shift; }
@@ -35,11 +36,10 @@ generate_std_and_exit() {
 }
 
 generate_big_and_exit() {
-       $debug && echo "Configuring: bb_common_bufsiz1[] in _end[], COMMON_BUFSIZE = $1"
+       $debug && echo "Configuring: bb_common_bufsiz1[] in bss, COMMON_BUFSIZE = $1"
        {
        echo "enum { COMMON_BUFSIZE = $1 };"
-       echo "extern char _end[]; /* linker-provided label */"
-       echo "#define bb_common_bufsiz1 _end"
+       echo "extern char bb_common_bufsiz1[];"
        echo "#define setup_common_bufsiz() ((void)0)"
        } | regenerate "$common_bufsiz_h"
        echo "$2" >"$common_bufsiz_h.method"
@@ -50,16 +50,11 @@ generate_1k_and_exit() {
        generate_big_and_exit 1024 "1k"
 }
 
-
-generate_malloc_and_exit() {
-       $debug && echo "Configuring: bb_common_bufsiz1[] is malloced"
-       {
-       echo "enum { COMMON_BUFSIZE = 1024 };"
-       echo "extern char *const bb_common_bufsiz1;"
-       echo "void setup_common_bufsiz(void);"
-       } | regenerate "$common_bufsiz_h"
-       echo "malloc" >"$common_bufsiz_h.method"
-       $exitcmd
+round_down_COMMON_BUFSIZE() {
+       COMMON_BUFSIZE=1024
+       test "$1" -le 32 && return
+       COMMON_BUFSIZE=$(( ($1-32) & 0x0ffffff0 ))
+       COMMON_BUFSIZE=$(( COMMON_BUFSIZE < 1024 ? 1024 : COMMON_BUFSIZE ))
 }
 
 # User does not want any funky stuff?
@@ -98,56 +93,45 @@ if $postcompile; then
        test x"$PAGE_SIZE" = x"" && exit 1
        $debug && echo "PAGE_SIZE:0x$PAGE_SIZE $((0x$PAGE_SIZE))"
        PAGE_SIZE=$((0x$PAGE_SIZE))
-       test $PAGE_SIZE -lt 512 && exit 1
+       test $PAGE_SIZE -lt 1024 && exit 1
 
        # How much space between _end[] and next page?
        PAGE_MASK=$((PAGE_SIZE-1))
-       COMMON_BUFSIZE=$(( (-END) & PAGE_MASK ))
-       echo "COMMON_BUFSIZE = $COMMON_BUFSIZE bytes"
+       TAIL_SIZE=$(( (-END) & PAGE_MASK ))
+       $debug && echo "TAIL_SIZE:$TAIL_SIZE bytes"
 
        if test x"$method" = x"1k"; then
-               if test $COMMON_BUFSIZE -lt 1024; then
-                       # _end[] has no enough space for bb_common_bufsiz1[]
-                       rm -- "$common_bufsiz_h.1k.OK" 2>/dev/null
-                       { md5sum <.config | cut -d' ' -f1; stat -c "%Y" .config; } >"$common_bufsiz_h.1k.FAIL"
-                       echo "Warning! Space in _end[] is too small ($COMMON_BUFSIZE bytes)!"
-                       echo "Rerun make to build a binary which doesn't use it!"
-                       rm busybox_unstripped
-                       exitcmd="exit 1"
-               else
-                       rm -- "$common_bufsiz_h.1k.FAIL" 2>/dev/null
-                       echo $COMMON_BUFSIZE >"$common_bufsiz_h.1k.OK"
-                       test $COMMON_BUFSIZE -gt $((1024+32)) && echo "Rerun make to use larger COMMON_BUFSIZE"
-               fi
+               {
+               echo $TAIL_SIZE
+               md5sum <.config | cut -d' ' -f1
+               stat -c "%Y" .config
+               } >"$common_bufsiz_h.1k.OK"
+               round_down_COMMON_BUFSIZE $((1024 + TAIL_SIZE))
+               # emit message only if COMMON_BUFSIZE is indeed larger
+               test $COMMON_BUFSIZE -gt 1024 \
+                       && echo "Rerun make to use larger COMMON_BUFSIZE ($COMMON_BUFSIZE)"
+               test $COMMON_BUFSIZE = 1024 && generate_1k_and_exit
+               generate_big_and_exit $COMMON_BUFSIZE "big"
        fi
 fi
 
 # Based on past success/fail of 1k build, decide next build type
 
 if test -f "$common_bufsiz_h.1k.OK"; then
-       # Previous build succeeded fitting 1k into _end[].
-       # Try bigger COMMON_BUFSIZE if possible.
-       COMMON_BUFSIZE=`cat -- "$common_bufsiz_h.1k.OK"`
-       # Round down a bit
-       COMMON_BUFSIZE=$(( (COMMON_BUFSIZE-32) & 0xfffffe0 ))
-       COMMON_BUFSIZE=$(( COMMON_BUFSIZE < 1024 ? 1024 : COMMON_BUFSIZE ))
-       test $COMMON_BUFSIZE = 1024 && generate_1k_and_exit
-       generate_big_and_exit $COMMON_BUFSIZE "big"
-fi
-if test -f "$common_bufsiz_h.1k.FAIL"; then
-       # Previous build FAILED to fit 1k into _end[].
-       # Was it with same .config?
-       oldcfg=`cat -- "$common_bufsiz_h.1k.FAIL"`
+       # previous 1k build succeeded
+       oldcfg=`tail -n2 -- "$common_bufsiz_h.1k.OK"`
        curcfg=`md5sum <.config | cut -d' ' -f1; stat -c "%Y" .config`
-       # If yes, then build a "malloced" version
+       # config did not change
        if test x"$oldcfg" = x"$curcfg"; then
-               echo "Will not try 1k build, it failed before. Touch .config to override"
-               generate_malloc_and_exit
+               # Try bigger COMMON_BUFSIZE if possible
+               TAIL_SIZE=`head -n1 -- "$common_bufsiz_h.1k.OK"`
+               round_down_COMMON_BUFSIZE $((1024 + TAIL_SIZE))
+               test $COMMON_BUFSIZE = 1024 && generate_1k_and_exit
+               generate_big_and_exit $COMMON_BUFSIZE "big"
        fi
-       # else: try 1k version
-       echo "New .config, will try 1k build"
-       rm -- "$common_bufsiz_h.1k.FAIL"
-       generate_1k_and_exit
+       # config did change
+       rm -rf -- "$common_bufsiz_h.1k.OK"
 fi
+
 # There was no 1k build yet. Try it.
 generate_1k_and_exit